Tuesday, April 29, 2008
THE APPLICATION OF PARETIANL CODE FOR ACCIDENT ANALYSIS ON INADVERTENT CONTROL ROD WITHDRAWAL FOR RSG GAS REACTOR
Azizul Khakim; Bapeten. Theanalysis is intended to take a look the condition of safety parameters such as fuel and cladtemperature, and minimum safety margin against flow instability (S) in the occurrence ofinadvertent control rod withdrawal at nominal power, which is performed by PARET/ANLCode. The accident is initiated when all control rods are simultaneously withdrawn withmaximum speed of 0.0564 cm/s which consequently gives maximum reactivity insertion rateLtplLtt = 2.82 x 10-4/s.resulting in the Reactor Protection System (RPS) respond to scram thereactor by dropping the control rods into the 'core. Theprimary cooling system is assumed to bein normal operation. It is postulated that thefirst trip signal from over power is not effective toscram the reactor. but only the second signal from Floating Limit Value eventually causes ascram with 0.5 s delays. During the occurrence of inadvertent control rods withdrawal at 30MW of initial power, the maximum fuel and clad temperature reach 181.29CCand 137.62CC,respectively and the peak power of 37.11MW. Meanwhile the minimum value of () reaches 2.62.Therefore, during the occurrence of control rods withdrawal at initial power of 30 MW, theintegrity of fUel and clad can be maintained secure since they do not exceed the maximum limitof fuel and clad temperature of 207 CCand 1~5 CC,respectively and the minimum value of S isstill higher than the design limit of 1.48for anticipated transient.Kev words: Application, PARET/ANL. Inadvertent Control Rod Withdrawal, RSG GAS
Read more ....
SAFETY STANDARDS AND CODES FOR NUCLEAR POWER PLANT IN THEUNITED STATES OF AMERICA.
Marsono Djoko Soebagijo; Badan Pengawas Tenaga Nuklir. The government .of Indonesia intended toestablishing the first Nuclear Power Plant (NPP) in the country. It is widely known thatnuclear safety is something paramount in NPP operation. The safe operation ofNPP ispossible when Safety Standards and Codes, is applied in .each step' of NPPestablishment. This paper decribes in general the Standards and Codes developed byt~e US, by which this country operates hundreds of NPP safely .. Further, thispresentetiqn is aimed to convey to competent institutions in Indonesia the urgency ofSafety Standards and Codes to be available jar governing the establishment of NPP inIndonesia. The reason of choosing Standards and Codes developed by the Us as majorreference in preparing this paper is" in addition to the fact that the US is one of manycountries which develop and operate NPP, it administers admirably the Safety,Standards and Codesfor NPP establishment.
Read more ....
STATUS PAPARAN RAD IASI ALAMIAH D I UNIT BISNIS PERTAMBANGAN EMAS PONGKOR, PT. ANEKA TAMBANG Tbk
Ajab Taofik Hidayat; UBPE Pongkor, PT. Antam Tbk. Pongkor Gold Mine Business Unit (UBPE Pongkor) is ones of six business units in PT. Antam Tbk.,which is located in Nanggung District, Bogor Residence, West Java. The geological exploration hadcarried out in 1988, and plant commenced in 1994 for 500 ton per day mill throughput. In 1997 theexpansion plant built for 720 tpd. The mining system is used underground with cut and fill type. Awaste solid tailing are used to pulfill stope ex-mine to maintain a continuously mining cycle. Theprocess plant are used conventional methods, a grinded ore is leached by sodium cyanide aschemical Reagents. A activated carbon is used for absorbs a leached gold and silver included aconcentration process. By sequential process from elution, electro winning, and smelting process tomade final product dore bullion (gold and silver alloys and sent to refmery Jakarta. Coarse tailingsolid are used for backfill material, and there are 2 (two) Waste Water Installation to reduce a restchemical before flow out system. Since 1997 Pongkor has a ISO 9000 Certified for Quality, and in2002 got ISO 14000 certified for Environmental.
Read more ....
Kajian Komparatif kekuatan dielektrik bahan isolasi kabel tanah terhadap tegangan impuls dan tegangan lebih bolak-balik
The investigation was carried out by applying the impulse and alternating current voltages to the insulation of NYY and NYFGbY cables. The dimensions of the cables selected were 4 x 10 mm2 for 0.6/l kV. The result of the research shows that the dielectric strength of the cable insulation under impulse voltage was 15% higher than that under alternating current voltage.Hamzah Berahim
Read more ....
DETERMINE A CAMERA POSITION USING GEODESIC DOME FOR MODELLING
This Paper present a method to determine a camera position to an object using a two dimension image.CCD camera is used to take an image. The geodesic dome is used for made model of the object. Thecamera is assumed to be at center of face in the geodesic dome and the model to be at center of thegeodesic dome. Therefore, if a model for the image can be determined, the position of camera to theimage can be known. Geometry calculation is used at matching process. Result of experiment will beshowed.Keywords: Geodesic dome, Pemodelan, Convex hull, Hough transform, MatchingM. Yoyok Ikhsan; Pusat Teknologi Elektronika Dirgantara - LAPAN
Read more ....
OPTIMATION .OF ENERGY USAGE IN ELECTRIC REACTOR
OPTIMATION OF ENERGY USAGE IN ELECTRIC REACTORCOOGENERATION SYSTEM AND HYDROGEN PRODUCTION WITH.GT-MHR(GAS TURBINE MODULAR HELIUM REACTOR). Akhmad KhoiruI Anam, Andang Widi Harto, Kusnanto; UGM. Review on two aspects HTGR aselectric (cQnversiQn) or heat energy source and hydrogen production is developing.Electrolyze on hydrogen production process. is most established technology frum"wa,tersplitting", by using DC current to divide water into oxygen and hydrogen gas.For high efficiency on industry scale, this process called as "high temperatureelectrolysis of steam "utilizing high temperature. Study and· consideration fromproduction and economiaspect is required so that found optimation from HTGR inusing temperature about 850 - 950 0
Read more ....
Konstruksi Jetty Medium Sebagai Alternatip Untuk Perbaikan Muara Sungai Tipar
At present, Tipar rivermouth is in unstable condition. The mounth often move from one to another, and it is often disturbed by sand spits that close the mounth during dry season. this condition reduces the capacity of the river and consequently causes flooding in the low area during the early wet season. To alleviate that problems several studies have been conducted, and the measures have been proposed. Due to a shortage of funding, the proposed design need to be reviewed and an alternative design has to be proposed. The alternative design should match the objective of the project in term of functionally as well as structural stability. This paper discussed and reviewed the proposed design and suggested a new alternative to meet the objectives of the project.Nur Yuwono
Read more ....
DAMPAK PEMBANGUNAN PLTN TIPE SMART DANDESALINASI TERHADAP EKONOMI WILAYAH DI JAW A TIMUR
Ratya Anindita; Dosen Unv. Brawijaya. Tujuan daristudi ini adalah untuk menentukan dampak ekonomi dari pembangtinankonstruksi PLTN Type SMART dan desalinasinya pada tahun2008-2017 di Madura,Provinsi Pulau Jawa Timur, Indonesia. Ramalan dari input output (10) pada periode2008-2017 digunakan oleh proyeksi (10) dinamis. Pembangunan konstruksi PLTNType SMART dan desalinasinya akan membutuhkan biaya sebesar 356,378 juta US$tetapi akan secara Iangsung mempengaruhi perekonomian domestik sebesar 101,8 jutaUS$ karena hanya sebagian pekerjaan dari konstruksi yang akan. dilaksanakan diIndonesia. Dampak Iangsung akan teralokasi pada tiga sektor yaitu, konstruksi, usahabangunan dan jasa. perusahaan. Dampak tidak Iangsung dari pembangunan tersebutakan menaikkan output perekonomian sebesar Rp., 2.647.815 juta dan efek terinduksisebanyak . Rp 1.405.68 juta dengan mengasumsikan nilai tukar pada Rp 1O.000/US$.Perhitungan ini akan memberikan total dampak bagi ekonomi dari Propinsi Jawa Timursebesar Rp 4.337.998 juta dengan tingkat partisipasi 'angkatan kerja sebesar 1.019.106.
Read more ....
RECENT RESEARCH ACTIVITIES ON CANDLE BURNUP
A new reactor burnup strategy CANDLE (Constant Axial shape of Neutron flux, nuclide densities and power shape During Life of Energyproducing reactor) was proposed in 2000, where shapes of neutron flux, nuclide densities and power densitydistributions remain constant but move upward (or downward) along its core axis. Since then many researchactivities have been performed in Tokyo Tech. In this paper these activities are summarized, and some otherimportant activities relating CANDLE burnup performed in the other institutes in the world are also introduced.Keywords: CANDLE, burnup, fast reactor, long-life reactor, safe, proliferation resistant. Recent Research Activities on CANDLE BurnupHiroshi SekimotoTokyo Institute of TechnologyO-okayama, Meguro-ku, Tokyo, Japan E-mail: hsekimot@nr.titech.ac.jp
Read more ....
CYBERMEDIA: SENI MEMADU KOMUNIKASI, TELEKOMUNIKASI DAN TEKNOLOGI
Budiono Darsono; Keterbukaan Web merupakan sebuah daya tarik yang sangat kuat. Siapa pun bukan hanyadapat membaca apa yang ada di Web melainkan juga memberikan sumbangsih, dan setiaporang berada dalam kesetaraan. Ada kesempatan yang tak terbatas di dalamnya - TimBerners-Lee, penemu Web-Ketika pertama kali dirancang beberapa tahun tahun lalu, Tim Berners Lee-penemu Web-barangkali belum membayangkan Web akan menjadi sedemikiandahsyat penggunaannya, dan menjadi kultur global setelah celana jeans dan minumanringan Cocacola. Ketika pertama kali digagas, Web hanya diilhami oleh kebutuhanLee untuk menemukan cara yang tepat membuat rujukan-rujukan dokumen dalampekerjaannya sehari-hari sebagai peneliti. Namun sekarang, teknologi Web bukan hanya menjadi teknologi untukmembuat sebuah dokumen terhubung dengan dokumen lain. Teknologi Web pada saatini telah menjadi alat yang tepat-guna untuk memperluas jangkauan publikasi danbahkan perdagangan yang interaktif: sebuah jembatan untuk komunikasi interaktifdengan jangkauan global. Kemudahan dan keterbukaannyalah yang agaknya membuat teknologi Webmenjadi sangat populer dewasa ini. Asalkan saja seseorang bisa memakai mouse,maka dia sudah dapat menikmati sajian di Web. Asalkan saja seseorang bisa mengertisedikit saja HTML, maka dia sudah dapat mempublikasikan banyak hal ke seanterobumi.Salah satu bidang yang sangat menikmati kemudahan dan keterbukaanteknologi Web adalah pers. Tidak lama berselang sesudah Web mulai banyakdikunjungi orang seantero bumi, pers online – kemudian dikenal dengan istilahcybermedia bermunculan. Dan pers Indonesia pun ambil bagian dalam trend ini.Pada awalnya, Indonesia dimulai pada tahun 95. Beberapa perusahaan perscetak memajang produknya di situs Web. Harian Republika dan Harian Kompas adalah contoh perusahaan pers di Indonesia yang mengawali pemanfaatan Web sebagaimedia publikasinya; dan lalu disusul oleh media -media cetak lain. Kini hampir semua perusahaan pers di Indonesia sudah memiliki versionlinenya. Dari serius mengelolanya hingga sekadar ‘punya’ web. Seakan versi onlineatau web ini bisa mengangkat gengsi perusahaan pers cetak, radio ataupun televisi. Kemudian muncullah detikcom yang menggarap beritaonline dengan memanfaatkan karakter sekaligus kemampuan Internet. Oleh banyakorang, detikcom dinilai sebagai pelopor praktek cybermedia di Indonesia.Cybermedia, memang sejak awal dirancang dengan mengakomodasi danmemanfaatkan kecanggihan, kemudahan, dan keleluasaan yang menjadi karakterteknologi Web.Web atau gampangnya disebut situs, eksistensinya tak lain berkat adanyarevolusi digital yang ditandai dengan munculnya teknologi Internet yang berbasis padaprotocol yang disebut TCP IP. Internet terdiri dari ribuan (bahkan jutaan) jaringankomputer lokal yang bersatu menjadi satu kesatuan global.Komunikasi di Internet didasarkan pada satu set protokol terbuka yang bisadipakai siapa pun yang ingin bergabung. Set protokol berinduk TCP/IP itu diterimasebagai tata cara "dialog" antar jaringan dan antar individu (komputer) yangmengisinya. Karena itulah kita bisa menikmati semakin banyak hal di Internet, mulaidari mengirim email, mendownload file, mengobrol (chatting) sampai menjelajah web. Internet pada dasarnya adalah alat komunikasi. Alat komunikasi yang relatifjauh lebih murah. Alat komunikasi yang memungkinkan orang bertukar data daribelahan bumi yang berbeda, dalam waktu seketika, hanya dengan menggunakan pulsatelepon lokal.Internet adalah sebuah perpustakaan raksasa. Miliaran data yang tersediamemungkinkan diakses siapa saja dari mana saja. Orang tinggal memilih. Mau dataserius yang dipublikasikan oleh lembaga-lembaga riset dunia, perguruan tinggibergengsi, data perusahaan-perusahaan, bahkan data pribadi tokoh-tokoh terkenal.Namun biang gossip tidak kalah banyaknya di Internet. Silakan pilih. Tinggal tekanmenu. Kemudahan dan keleluasaan merupakan salah satu karakter teknologi Internet,bukan saja harus dimanfaatkan, melainkan juga harus diakomodasi oleh pers.Namun demikian, di luar sisik melik Internet, seringkali ada ancaman kegagalanuntuk memanfaatkan dengan baik karena justru oleh ketidakmampuan memilah danmemilih berbagai kehandalan teknologi. Seperti yang telah kita ketahui bersama, saatini teknologi Internet memiliki banyak kemampuan dan masih terus dieksplorasi olehberbagai pihak. Kunci penting agar Internet termanfaatkan dengan baik, mampumemacu efektivitas, efisiensi serta memberi kemudahan dalam bekerja, tak lain adalahadanya sebuah kesadaran penuh, bahwa Internet adalah perpaduan seni komunikasi,telekomunikasi dan teknologi. Budiono Darsono; Pemimpin Redaksi Email: budiono@detik.com
Read more ....
FLUTTW2D : A SOFTWARE TOOL FOR FLUTTER PREDICTION ON AIRPLANE WINGS
The structure of an aircraft wing is relatively similar to a cantilever, a cylindrical beam with oneend fixed and the other end free. There are two dominant directions of motion, heaving and pitching. In acertain type of wing, flutter phenomenon can be analyzed from its 2D airfoil profile and its material characteristic. FLUTTW2D is a practical software tool to predict the flutter critical velocity of this typicalwing. The following paper describe basic concepts of the software design, including its appliedconditions, theory and physical equations which are referenced by the algorithm or FLUTW2D software. Keywords : flutter, airplane wings, computationFariduzzaman; UPT-LAGG BPPTeknologi, PUSPIPTEK, Serpong
Read more ....
Activities in COE-INES
ACTIVITIES IN COE-INES. In the year 2002 and 2003 the Japanese Ministry of Education, Culture,Sports, Science and Technology started the 21st Century Center of Excellence (COE) Program. A programproposed by Tokyo Institute of Technology “Innovative Nuclear Energy Systems for Sustainable Development ofthe World (COE-INES)” was selected as only one program in nuclear engineering field. It is a 5-years program,and now we are summarizing our activities. During this period, the researches on innovative nuclearengineering have been progressed successfully. Education of doctoral course students has been also promotedintensively by introducing new courses of curriculum and offering research assistantships. Many students havemany chances to go abroad to attend international conferences. Social affairs are also considered important,and many events are prepared for it, including CSR (Corporate Social Responsibility) seminars and ethicseducation. International collaboration is important, and we had held many international and by-lateralsymposiums and workshops in Japan as well as foreign countries. The settlement of the Center for Research intoInnovative Nuclear Energy Systems (CRINES) is also an important result. Our activities cover wide areas onnuclear engineering.Keywords: COE-INES, Innovative Nuclear Energy Systems, 21st Century Center of Excellence Program,Research, Education, International, Social Responsibility, Tokyo Institute of TechnologyHiroshi SekimotoTokyo Institute of TechnologyO-okayama, Meguro-ku, Tokyo, JapanE-mail: hsekimot@nr.titech.ac.jp
Read more ....
AEROCO: SOFTWARE TOOL FOR DETERMINING AERODYNAMIC COEFFICIENTS OF A LONG-SPAN BRIDGE MODEL
Prediction of structural instability of along-span bridge is usually conducted in a wind tunnel test, where the aerodynamic as well as aeroelasticaspect of the structure can be tested by means of 2 or 3 dimensional model. In a 2 dimensional model, inspite of testing the physical model, a mathematical model should also be constructed. Initially, this mathematical model has unknown parameters that must be determined from experimental data. In otherwords, the determination of aerodynamic coefficients is part of system identification of aeroelasticequations for predicting the critical margin of the bridge structure. The following paper will describe thedevelopment of a software tool for extracting the aerodynamic coefficients of a sectional model test (2 dimensional) in the ILST (Indonesian Low Speed Tunnel). Keywords: long span bridge, wind tunnel testFariduzzaman; UPT-LAGG BPPT, PUSPIPTEK, Tangerang-15314, INDONESIA farid@lagg.or.id
Read more ....
INDONESIA-DLN IS A DIGITAL LIBRARY NETWORK IN INDONESI
Within thispaper, philosophy of the knowledge sharing, vision of the network, and how it can give benefits toIndonesia are described. The status of the network is described that show the successfulness of thearchitecture in tying together partner’s knowledge from all big islands of Indonesia (Sumatera, Java,Kalimantan, Sulawesi, and Irian Jaya) whether they have dedicated internet connection or only a dial-upone. Currently 13 institutions have joined the network and 15+ in progress of developing their servers.Features of the software, Ganesha Digital Library (GDL version 3.1) are presented, that is now distributedas a Free-Software that is based on MySQL, PHP, and Apache.Ismail Fahmi; Sekjen IndonesiaDLN, dan Ketua Knowledge Management Research Group – ITB, ismail@itb.ac.id
Read more ....
Unjuk kerja rheomac SF 100-MB-SF dan Rheobuild 100 terhadap kuat tekan beton dengan agregat normal
The conventional concrete which made with normal aggregates should be able to fullfill the improving of concrete technology where the high strength concrete was needed to support the load in order to minimize the building cost. Theomac SF 100-MB-SF admictures in the form of mineral material that have a high silica content and fineness of a aggregates. Rheobuild 1000 admixtures is one type of superplasticizer and will act as water reducing agent and minimizing water cement ratio. Combination of the two admixtures would give one alternative solution in order to get a high strength concrete. The research was run by making cylinder specimens and tested in 28 day age. The parameters of the research were water cement ratio and content of Rheomac SF 100-MB-SF and Rheobuild 1000. The results showed that the specimens which made with the addition of Rheomac SF 100-MB-SF and Rheobuild 1000 have very high compressive strength. By using water cement ratio of 3.0, the addition of Rheomac SF 100-MB-SF of 0%, 5%, 10% and 15% gave compressive strength of 65.135 MPa, 66.56 MPa, 81.74 MPa, and 95.698 MPa respectivelly, and 80.541 MPa, 84.059 MPa, 86.883 MPa and 85.427 MPa for water cement ratio of 3.50.Sudarmoko
Read more ....
200 MW(T) Pb COOLED FAST REACTOR NEUTRONIC DESIGN
Neutronic design of200 MW(t) Pb cooled fast reactor which life time 20 years have been performed using FI-ITBCHIsoftware package . The constraint parameter of the design is excess reactivity not exceeded 0.2 ?k/k %.The excess reactivity of this design is 0.174 ?k/k % and the dimension in the axial direction is greater than radial direction.Epung Saepul Bahrum*, Zaki Su’ud*, Abdul waris*, Bambang Ari Wahjoedi**; * Jurusan Fisika ITB ** Jurusan Kimia ITB
Read more ....
STUDI SIFAT PB-BI DENGAN METODA MOLEKULAR DINAMIK LEAD-BISMUTH ALLOY STUDY WITH MOLECULAR DYNAMIC METHOD
Lead-Bismuth alloy had been simulated by molecular dynamic method. Parameters Lennard-Jones potential aretaken from data available in the literature which the interatomic potential calculated by ab-initio method.The result of molecular dynamic proceses showed good conservation of total energy accuracy withrespect to the time step in the order 10-10. The radial distribution function with variation of temperaturehad shown the liquid state of alloy at 396.5 K, 579,71 K. But at 275,36 K the simulation showed theliquid state also. In fact at this temperature, It should be in the solid state.Keywords: Lead-Bismuth, Molecular dynamic, Radial Distribution Function.Alan Maulana*, Zaki Su’ud*,Hermawan K.D**, Khairurijal*; * Departemen Fisika MIPA ITB ** Departemen Fisika Teknik ITB
Read more ....
Armor layer stability coefficient under nearly breaking and broken wave attack in limited depth condition
The use of breakwater for coastal and harbor area protection against wave attack is very common. Yet there are still many uncertainties found in the design of such a structure particularly the rubble mound breakwater. This type of breakwater may be repaired after slightly damage due to wave attack The flesible armor layer that is dump randomly over to protect the main body of the structure made it repairable. The design of the cover layer which may only suffer slingtly (5% damage) under an extreme wave condition is challenging. There have been many formulae available usually with limitation to ists utilization. The Hudson formula is widly used, although it is limited to many conditions. Nroken wave attack is one condition in which the Hudson formula may not be used. A broken wave condition is the condition where some of the wave have broken before reaching the structure due to shallow water (limited depth) condition. The research is aimed at finding the effect of broken wave to the stability of armor layer. A rubble mound breakwater model was constructed and attacked by irregular nearly breaking and broken wave in a flume. The results showed that a coefficient should be added to the Hudson formula to justify its utilization for broken wave condition.Radianta Triatmadja
Read more ....
RADIATION APPLICATION IN IMAGING DIAGNOSTIC AND RADIOTHERAPY
R. Susworo; Radiologist, Faculty of Medicine University of Indonesia;Cipto Mangunkusumo General Hospital X-ray was invented by WC Roentgen in 1895. It became an important milestone in thedevelopment of radiology, either for diagnostic purpose and the treatment of cancer usingradiotherapy modality.In the diagnostic field, the usage of X-ray covering a lot of methods which rapidly developedparallel with the advanced of technology. It was initiated just after the discovery of thismiracle beam. Conventional radiology is the simplest imaging method. This method occupies the mostfrequent examinations such as chest tuberculosis, lung cancer, emphysema, etc and theheart to detect enlargement. Examination of the bones due to fracture or degenerativeprocess become the second most frequent examination. The role of this plain film todetect bone tumours was replaced by CT Scan in the last decades. To identify opaquestone in the urinary tract, kidneys or ureter, or biliary tract, a plain abdominal film issufficient. The occurrence of the stone should be followed by another radiologyexamination(s).To depict organs consisting of soft tissue, the administration of contrast materials issometimes required. Iodine content dye materials is commonly used in the examination ofurinary tract and blood vessels. While sulfate barium in a porridge from substance isimportant to delineate hollow organs such as the intestine.Mammography was accepted as an imaging diagnostic tools to detect (early) cancer ofthe breast. A lot of publications have reported the importance of this examination on highrisk women and a long epidemiological studies have proven that this routine examinationhas lowered mortality rate of women suffer from breast malignancy.In the developed countries there are significant increase of death rate caused bymalignant diseases, heart infract, and cerebal hemorrhage. Several radiologicalexaminations have been developed to identify those ailments. Angiography is one ofsome modalities in the attempt of depicting abnormalities 1n the blood vessels or relatedto it. This examination is applied in clinically suspected tumour of certain organs (liver,brain, kidney) or malformation (A VM), blood vessels abnormalities (stenosis, aneurysm).The advanced of technology has allowed the physicians to examine more than theycould do in the past. The first generation of CT Scan has been used in the medical field inthe mind sixties. Nowadays, three dimensional CT Scan or CT Angio is available to getmore information from various diseases in order to establish proper diagnosis.Nuclear medicine is another modality using radioactivity for either diagnostic andtherapeutic purposes. SPECT and PET are the most recent development in this field. In the treatment of cancer, radiotherapy is now known as radiation oncology due to the factthat in implementing this modality either physics aspects of radiotherapy and oncology playimportant role. Radiation Oncology has been accepted as one of treatment modalities in themanagement of cancer since years, in complementary with surgery and chemotherapy.It is cosidered as cheap and non invasive method.PROCEEDING PUBLIC INFORMATION SEMINARON THE APPLICATION OF NUCLEAR SCIENCE AND TECHNOLOGY FOR HUMAN WELFAREJAKARTA, FEBRUARY 13-15,2001~ Some early stage cancers could be cured by radiotherapy as single modality. PaJliativeintention could be achieved by late stage patients in Order to alleviate the symptoms andto improve the quality of life.Radiation beams used consists of generated beams, : X-ray, neutron, proton, heavy ionsand radioisotopes: Cobalt-6O, Radium-225,Caesium-137, lodine-133, Iridium-194, etc.The discovery of various isotopes and treatment methods (afterloading, comformationtechnique, IMRT, etc.) has significantly improved local control and increased survival rateof cancer patients. On the other hand it lowered the radiation side effects.
Read more ....
THE EFFECT OF NPP'S STACK-HEIGHT TO RADIATION DOSE
Liliana Yetta Pandi, Budi Rohman: Bapeten. The Purposeof dose calculation for accidents is to analyze the capability of NPP to maintain thesafety of public and workers in case an accident occurs on the Plant in a site. Thispaper calculates the Loss of Coolant Accident in PWR plant. The calculation resultsshows that no risks of seriousradiation exposureare given to the neighboringpublic -even if such a large accident occurred, and the effect of stack height can bepredicted byanalysis of the calculation results. The whole dose is calculated for some location (100-m' 300 m, 500 m, 700 m, 900 m, 1500 m and 2000 m) with three difference stack heighti.e. 0 m, 40 m and 100 m. The result of the whole dose calculation is under permittedcriteria for whole dose: 0.25 Sv and thyroid dose: 3.0 Sv. The calculation of radiationdose in thispaper use EEDCDQ code.Kevwords : whole dose, thyroid dose, stack height, EEDCDQ
Read more ....
PERSEPSI MASYARAKAT TERHADAP PEMBANGKIT LISTRIK TENAGA NUKLIR (PLTN)
A. M. Djuliati Suroyo; Pusat Penelitian Sosial Budaya,Lembaga Penelitian Universitas Diponegoro (UNDIP). Preliminary research on the perception and resistance of the people concerninggovernment's plan to build a nuclear power plant for electricity at Muria peninsula, in Jepara,has that some people refused, some were ready to accept, and somejust he!s'itated.In generalthe beaurocrats accepted the plan, although some felt doubtful since they are in change ofenvirontment conservation. Parliament members and religious leaders have the tendency to bedoubtful in response of the goverment's plan on nuclear power plant. Those NGO members,especially theSe under young aclivist' leaders have refused the plan, while other religiousleaders and some rural leaders tend to accept-it.The various perception and attitudes which exist in the society are Inostly caused byconditions such as one's position, his group's perception in which he attached to, and factorseither socio-cultural, socio-political, or socio economics. Especially those with negativeperception were actually influenced by thefeeling of distrust to the government. 'At this time the government is trying to rebuild people's confidence by planning somedevelopment programs with bottom-up approach, but since it has a bad reputation in the post,that different attitudes have emerged toward state's projects, since in the past many personshave corrupted the project they carried-out for their own benefit,The various attitudes of the people toward the government have their impact on thegovernment plan to build nuclear plant in Jepara. In this situation it will be more who reject theplan. To this moment is seems that the government has not succes.sfully changhd its image tohave public trust, due to their prejudice to government projects, more over for its nuclearpowerplant. Input of informafion, especially about nuclear. They select information aboutnuclear mostlyfrom the negative side only, although there should be also positive side.
Read more ....
THE COMPUTER PROGRAM OF FAUILURE TREE ANALYSIS USING NUMERICAL SIMULATION
It was composed computer program of fault tree analysis using numerical simulation,that is called Fault Tree Simulation Program (SIMPOK). This program can be used for qualitative analysisi.e. to determine minimal cut-set (MCS), and quantitative analysis i.e. to calculate frequency anduncertainty of top event. The test was conducted and compared to Monte Carlo Program. The programsuccesfully operated and the calculation result was relatively the same as Monte Carlo.Keywords: computer program, fault tree, simulation, minimal cut-setHaendra Subekti; Direktorat Perijinan Instalasi Nuklir - BAPETEN
Read more ....
COMPUTATION OF DYNAMIC FLUID FLOW USING DIGITAL IMAGE ANDpiv (PARTICLE IMAGE VELOCIMETRY) PARTICULARLY IN NUCLEAR APPLICATION
Two images captured sequentially in Dt period, by CCD camera and double-pulse laser in cross-section offlow with seeding particle, were reviewed. The digitalized images were calculated by FFT method, cross correlationand auto-correlation as an impulse function equation, therefore inversed in to time domainr esulting velocity vector maps with known Dt . The computation result can be applied in a large technical application, especially in nuclear application, turbulence and the other phenomena fluiddynamic in reactor chamber which can be calculated providing Laser, CCD camera and remotely computational equipment are available. BPP Teknologi; BPP Teknologi.
Read more ....
INTEGRATOR PERFORMANCE ANALYSIS IN SOLVING STIFFDIFFERENTIAL EQUATION SYSTEM
In this paper we discuss the four-stage index-2 singly diagonally implicitRunge-Kutta method, which is used to solve stiff ordinary differential equations (SODE). Stiff problemsrequire a method where step size is not restricted by the method's stability. We desire SDIRK to be Astablethat has no stability restrictions when solving y= ly with Rel and, so by choosing suitablestability function we can determine appropriate constant (g) to formulate SDIRK integrator to solve SODE. We select the second stage of the internal stage as embedded method to perform low orderestimate for error predictor. The strategy for choosing the step size is adopted from the strategy proposedby Hall(1996:6). And the algorithm that is developed in this paper is implemented using MATLAB 5.3, which is running on Windows95 environment. Our performance measurement’s local truncation erroraccuracy, and efficiency were evaluated by statistical results of sum of steps, sum of calling functions,average of Newton iterations and elapsed times. As the results, our numerical experiment show thatSDIRK is unconditionally stable. By using Hall's step size strategy, the method can be implemente defficiently, provided that suitable parameters are used.Alhadi B. dan T. Basaruddin; Jurusan Matematika, FMIPA–Universitas Indonesia Fakultas Ilmu Komputer– Universitas Indonesia
Read more ....
Intensive Pre-Incan Metallurgy Recorded by Lake Sediments from the Bolivian Andes
The history of pre-Columbian metallurgy in South America is incomplete because looting of metal artifacts has been pervasive. Here, we reconstruct a millennium of metallurgical activity in southern Bolivia using the stratigraphy of metals associated with smelting (Pb, Sb, Bi, Ag, Sn) from lake sediments deposited near the major silver deposit of Cerro Rico de PotosÃ. Pronounced metal enrichment events coincide with the terminal stages of Tiwanaku culture (1000 to 1200 A.D.) and Inca through early Colonial times (1400 to 1650 A.D.). The earliest of these events suggests that Cerro Rico ores were actively smelted at a large scale in the Late Intermediate Period, providing evidence for a major pre-Incan silver industry. Mark B. bbott1 and Alexander P. Wolfe2; 1 Department of Geology and Planetary Science, University of Pittsburgh, Pittsburgh, PA 15260, USA.2 Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, AB T6G 2E3, Canada.
Read more ....
IMPROVEMENT OF TREATMENT PLANNING SYSTEM AT JAEA (JCDS) FOR BORON NEUTRON CAPTURE THERAPY
Clinical trials of boron neutron capture therapy (BNCT) are being carried out using theJapan Research Reactor No.4 (JRR-4) in Japan Atomic Energy Agency (JAEA). BNCT is a sort of radiationtherapy for an obstinate cancer like a malignant brain tumor. The BNCT clinical trial at JRR-4 has been carriedout since 1999. To carry out the clinical trials based on accurate dosimetry, JAEA Computational DosimetrySystem (JCDS), a treatment planning system for BNCT, was developed by JAEA. To predict the neutrons andphotons behavior around an irradiation field of a patient, JCDS creates a detailed 3D model of a patient usingmedical images, and then the 3D model is converted into a voxel model. Distributions of neutron flux thecorresponding several doses in the voxel model are determined using Monte Carlo transport code, MCNP.BNCT clinical trials for malignant brain tumor derived from a proper treatment plan with JCDS were begun atJRR-4 in October 2003. To enhance the accuracy of dosimetry calculations, JCDS has been improved to create adetailed voxel model consisting of minute voxel cells as small as 2x2x2mm. To calculate the distributions of thefluxes and doses effectively, JCDS has employed transport calculations with “mesh tally” option installed inMCNP version 5. By using the mesh tally option, the computing time can be shortened significantly. Applicationof the minute voxel calculation combined with mesh tally improves the accuracies of dose evaluation so that anoptimum treatment planning for not only the malignant brain tumor but also the head-&-neck cancer can besuccessfully performed.Keywords: BNCT, JRR-4, treatment planning system, MCNP, dosimetry. Improvement of Treatment Planning System At JAEA (JCDS)For Boron Neutron Capture TherapyH. Kumada1*, K. Yamamoto1, Peng Hong Liem2, A. Matsumura3 and Y. Nakagawa41: Japan Atomic Energy Agency, Japan2: NAIS Co., Inc, Japan3: University of Tsukuba, Tsukuba, Japan4: National Children’s Hospital, Japan*E-mail: kumada.hiroaki@jaea.go.jp
Read more ....
Mekanika Aliran Airtanah Pada Akifer Karst: Melalui Saluran Fraktal
In mathematical modeling of groundwater flow mechanics through conduit system, generally the cross sectional area of a karst conduit is non-circular, even tend to be irregular. This irregularity causes the karst conduit difficult to be defned as euclidean geometry, but more appropriately presupposed as fractal geometry. Therefore, dealing with groundwater in karstic aquifer, some flow mechanics equations such as Bernoulli equation, need to be reviewd. This paper tries to develop some existing flow mechanics equations to make those acomodatable for fractal geometry. It is expected that the more acurate results will be acquired.Sari B. Kusumayudha, MT. Zen, Sudarto Notosiswoyo, dan Rudy Sayoga Gautama
Read more ....
Batan Grande: A Prehistoric Metallurgical Center in Peru
Recent archeological fieldwork on the north coast of Peru permits a preliminary reconstruction of a prill-extraction copper and copper alloy smelting process heretofore undocumented in the New World. The process was applied on a large scale during the late pre-Hispanic period. This study provides strong support for the claim that central Andean metallurgy constituted one of the major independent metallurgical traditions of the world.Izumi Shimada 1, Stephen Epstein 2, and Alan K. Craig 3; 1 Assistant professor of anthropology at Princeton University, Princeton, New Jersey 085442 Graduate student in the Department of Anthropology and research assistant at the Museum Applied Science Center for Archaeology, University of Pennsylvania, Philadelphia 19104; 3 Professor of geography at Florida Atlantic University, Boca Raton 33431
Read more ....
APPLICATION OF CLUSTER ANALYSIS ON INTERNET-BASED INFORMATION RETRIEVAL SYSTEM
Since much information is available in the Internet, there is more difficult tofind out a relevant information. For many Internet users, search engine cannot solve this problem.Clustering engines that apply of cluster analysis provide an alternative way to find out the relevantinformation among the much information that scattered around the Internet. Vivisimo is a clusteringengine that clusters documents have been indexed by many search engines. Based on the user’s query,Vivisimo does a meta-search to the indexing results of many search engines. The results of meta-searchare clustered to many clusters, which labeled using dominant characteristic of the cluster, and thendisplayed for the users. The clusters that were formed can help users with guidance to browsing and make an interpretation or relevant judgement the searching results. Therefore, it can be said that clusteringengine give a benefit for user to find out the relevant information in the Internet. On the other hand,search engines can give more comprehensives searching results. So, the clustering engine and searchengines can be used complementary in the successive searching to get easier searching withcomprehensive results.Miswan*; Mustangimah**; * Mahasiswa Program Studi Ilmu Informasi, Perpustakaan, dan Kearsipan; Program Pascasarjana, Universitas Indonesia ** Pusat Pengembangan Teknologi Informasi dan Komputasi - BATAN
Read more ....
GRAY LEVEL CO-OCCURRENCE MATRIX FEATURE EXTRACTION
GRAY LEVEL CO-OCCURRENCE MATRIX FEATURE EXTRACTION ANDPROBABILISTIC NEURAL NETWORK FOR WELDING DEFECTS RECOGNITION. In thispaper, we have developed Defects Recognition Systems on Metal Welding based on Gray Level CooccurrenceMatrix Texture Feature. The X-ray films used in this research are IIW (International Instituteof Welding) standard of radiograph technique. The first step is X-ray film digitalized, using a digitalcamera on X-ray interpreter. The next step is feature extraction; in this step co-occurrence matrix isdeveloped. The value of angular second moment, correlation, inverse difference moment and entropy arecalculated as texture feature on one distance and four directions. Probabilistic Neural Network is used as adefect classifier to classify the output of the systems. Recognition output is classified into 8 classes, thatis 1st class (normal/without defect), 2nd class (distributed porosity), 3rd class (incomplete penetration), 4thclass (burn through), 5th class (cluster porosity), 6th class (excessive cap), 7th class (excessive penetration) and 8th class (incomplete fusion). Three methods of training testing data sampling (random, semi randomand choosing) are compared in this research. Average of recognition on this system is 99,54 % using training testing paradigm 1 : 1.Key words: Welding defect, Recognition, Neural Network, Texture Extraction.Adhi Harmoko S*, Benyamin Kusumoputro**, Makmur Rangkuti***; * Departemen Fisika FMIPA, Universitas Indonesia, Depok 16424, email : adhi_hs@fisika.ui.ac.id ** Fakultas Ilmu Komputer, Universitas Indonesia, Depok 16424 *** PUSDIKLAT BATAN, Ps Jum’at, Jakarta Selatan
Read more ....
Perbandingan hasil analisis evolusi jaringan syarag buatan yang simbiotik dengan metode sane dan ESP
Symbiotic Adaptive Neuro Evolution (SANE) and Enforced Sub-Population methods (ESP is the development of SANE) are developments of evolution concept to acquire artificial neural networks using genetic algorithm. In this study Sane and ESP will be applied to solve WarCraft-Like game. After several experiments have been done, an observation of the algorithms and experiment results is conducted to show ESP's advantages compared to SANE's and vice versa and changes made by ESP to SANE's dependency on divergence that is contradictory to genetic algorithm. Keywords: artificial neural network, genetic algorithm, symbiotic adaptive neuro-evolution, enforced sub-populationsby. Andre Iskandar and Handayani Tjandrasa
Read more ....
TAKING OF OPTIMAL SAMPLE NUMBER BY USE OF SAMPLE INFORMATION VALUE FUNCTION
To reduce ambiguities in decision making, we can take information sample beforea decision teken. This procedure can incrrease the additional cost. Due to acuiring an optimal samplenumber, we use the Bayesian theory and sample information value function. The ddevelopment of thisprogram simulation lead to enhance understanding about the sumple number should be taken.Sri Redjeki, Enny Itje Sela; STMIK-AKAKOM Yogyakarta
Read more ....
STUDI TENTANG PEMANFAATAN PLUTONIUM DALAM PWR DENGAN BURNUP STANDARD
Abdul Waris dan Rai Falihah; E-mail: awaris@fi.itb.ac.id. Studi tentang pemanfaatan plutonium dalam PWR dengan bumup standard telah dilakukan. Konsentrasi plutonium dalam MOX divariasikan bemilai 1%-20%. Untuk ketiga jenis konsentrasi U-235 dalam uranium, yaitu tail 0.1% dan 0.3% serta uraniumalam, diperoleh hasil bahwa kondisi kritis rektor dapat dicapai dengan minimal jurniah plutonium 2.75% dan maksimal10%, Untuk komposisi dengan 2.75% - 4% plutonium desain reaktor yang baik adalah desain dengan moderasi tinggi, sementara, komposisi dengan 5% - 10% plutonium memberi hasil yang diinginkan bila digunakan dalam reaktor dengan desain tight lattice.Kata kunci:, plutonium, standard bumup, daur ulang, limbah nuklir, ayunan reaktivitas
Read more ....
PENGATUR SUHU TINGGI PAD A SISTEM PERALATAN PERMEASI ...
PENGATUR SUHU TINGGI PAD A SISTEM PERALATAN PERMEASI Nyoman Gede Suyasa PENGATUR SUHU TINGGI PADA SISTEM PERALATAN PERMEASI. Telah dilakukan penelitian pengatur suhu tinggi pada peralatan karakterisasi material dengan metoda permeasi hidrogen. Untuk mendapatkan sistem thermal yang presisi dan homogen makaalat pengatur suhu dirancang melalui analisis model. Sebagai sensor suhu digunakan thermokopel tipe-k inconel-600, sensor ini dipasang pada permukaan sam pel sisi-bawah. Dari hasil komputasi analisa distribusi panas operasi sampel pad a suhu gOODCdenan EMRC NISA-II diperoleh perbedaan suhu maksimum dan minimum sebesar 15 C.Dengan batas toleransi suhu peristiwa permeasi hidrogen sebesar 25DC, maka dapatdipandang bahwa penempatan sensor thermokopel memenuhi syarat. Rangkaian elektronik lokal panel digunakan IC amplifier thermokopel A0595 yang dilengkapikompensator persambungan-dingin, sedangkan untuk pengubahan sistem sinyal analogke tampilan digital digunakan ICL7107. Rangkaian akuisisi data dan kendali remotedigunakan link komunikasi multidrop RS-dengan modul AOAM4011 sebagai 'remoteterminal unit' (RTU) dan PC sebagai stasiun kendali. RTU diprogram sebagai kontrolerON/OFF pita-histerisis dan pernberian daya listrik ke elemen pemanas melalui SSR 30A250V. Bahasa pemrograman yang digunakan adalah C. Pengujian pengukuran suhu dankelakuan kendali menunjukkan hasil yang baik untuk jangkauan 25 sId 11aoDc.
Read more ....
PENGGUNAAN METODE PNDAN SNUNTUK PERPINDAHAN KALOR RADIASI PADA REAKTOR NUKLIR TERFLUIDISASI
(Studi Kasus untuk Pengambilan Kalor Peluruhan Secara Pasit) Alexander Agung; email: a.agung(@gmail.com. and Danny liathouwers, Tim van der Hagen, Hugo van Dam. Numerical simulations have been performed to investigate the possibility of passivedecay heat removal in a fluidized bed nuclear reactor. The conduction, convection andradiative heat transfer were included arid the high Reynolds number k-e turbulencemodel was applied for the flow calculations. The Pj and SN approximation methods forparticipating media were used for the radiation model. The reactor was modeled as a2D axisymmetric cylinder. Calculations were performed for an initial operating powerof 60 MW. The results show that P j method is quite good to be applied in the particlebed' but it fails in the freeboard. The high order SN method can be applied extremelygood both in the particle bed and the freeboard. The drawback of the SN method is itslong computational time. The invalidity of Pj method leads to a high fuel particletemperature, exceeding its allowable maximum value. Such situation, however, does notoccur in the SN method.Kevwords: decay heat, fluidized bed l'!uclear reactor, passive heat removal, numericalsimulation, PN methods, SN methods
Read more ....
THE TOP 10 ALGORITHMS OF THE 20TH CENTURY
The following is a list and a shortdescription of the “Top 10 Algorithms of the 20th Century” selected by the editors of Computing inScience & Engineering / CiSE, and was the main issue of its Jan-Feb. 2000 edition. These were the 10algorithms with the greatest influence on the development and practice of science & engineering in the20th century, and was supposed to be a resume of the development of numerical mathematics andcomputational science throughout the 20th century. We may agree or disagree with this selection, but theleast we should do is not to underestimate them, because they are the opinions of highly qualifiedcomputational scientists in advanced countries. The editors have asked the readers of the journalregarding their opinions and feelings about this selection. It turned out that in the following issues ofCiSE, there were only agreements and no disagreements regarding the selection. It may be concluded,therefore, that CiSE’s selection was well done and well received by the international scientificcommunity.M. Bunjamin; FMIPA-UI and FMIPA-UNAS
Read more ....
Late-Holocene atmospheric lead deposition in the Peruvian and Bolivian Andes
The analysis of lead (Pb) in lake-sediment cores is a useful method to reconstruct local histories of Pb pollution. Here, we use Pb concentration profiles from lake sediments to reconstruct local trajectories of pre-Colonial smelting from three metallurgical centres in the South American Andes: the Morococha mining district, Peru the Bolivian Altiplano around Lake Titicaca; and the silver-mining centre of PotosÃ, Bolivia. The earliest evidence for Pb enrichment from smelting is on the Altiplano beginning ~AD 400, coincident with the rise of the pre-Incan Tiwanaku and Wari Empires. Coeval with the collapse of these Empires ~AD 1000, there is a dramatic decrease in Pb pollution on the Altiplano, suggesting metallurgical activity was closely tied to the Tiwanaku state. In contrast, metallurgy at Morococha, Peru and PotosÃ, Bolivia began ~AD 1000—1200, likely as the result of the diaspora generated by the collapses of Tiwanaku and Wari. The independent chronologies of these records suggest asynchronous metallurgical activity between mining centres, and local-scale control of mineral resources. Following Inca conquest of the Andes ~AD 1450, strong increases in Pb are noted at all three study sites, suggesting an increase in silver production to meet Inca imperial demand. Following Hispanic conquest (AD 1532), large increases in Pb pollution are noted at Morococha and PotosÃ, only to be superseded by industrial development. The records presented here have implications for the reconstruction of Andean prehistory, and demonstrate the sensitivity of lake sediment geochemistry to pre-Colonial smelting activity. The technique has much potential for exploring the timing and magnitude of pre-industrial metallurgy in the New World. Key Words: Atmospheric lead deposition • Pb • Andes • lake sediments • metallurgy • pollution • geoarchaeology • late Holocene • Peru • Bolivia. by Colin A. Cooke, Mark B. Abbott and Alexander P. Wolfe.
Read more ....
The Wear Testing Of Glass-Fiber/Epoxy Composites
The aim of this work was to investigate the wear rate behaviour of glass-fiber/epoxy composites, concerning the fiber contents and the variantion of disc velocity. Three different fiber contents of glass-fiber/epoxy composites were tested in a revolving disc wear testing machine. The specimens were tested in a paraticular wear distance, pressure, and fiber orientation. The velocity of the revolving disc was varied in three different velocities. The result of the investigation shows that the fiber content and the velocity of revolving disc influence the dimensionless wear rate, the spesific wear rate and the time-related depth wear rate.Suyitno and Jamasri
Read more ....
Decomposition applied to Stratoconception using parting lines
Parting lines enable visible and invisible parts of a geometric model to be separated in a given direction. In this paper, parting lines were defined. The required mathematical models, and an algorithm for computation of parting lines were established. A method involving the use of this concept in the manufacture of a model by Stratoconception was described. Compared with conventional methods, this concept achieves a higher accuracy. KEYWORDS: Parting line; Visibility; Polyhedron; STL; Rapid prototyping; Stratoconception Yves HOUTMANN, Benoit DELEBECQUE, Geoffroy LAUVAUX, Claude BARLIER
Read more ....
ACQUISITION SYSTEM AND TURBULENT FLOW DATA PROCESSINGUSING ULTRASONIC VELOCIMETER
Turbulent Intensity (e) is an important parameter on fluid flowanalysis, because several physical phenomena are influenced by the parameter. As part of wind tunnelaerodynamic testing, LAGG has developed a measurement system for turbulent flow, namely softwaresystem for data acquisition and processing of ultrasonic velocimeter, DAQ controller and ultrasonictransducer. Although the system was developed for airflow, the system can also be used to measuregeneral fluid dynamic cases, liquid or gas (wind), open environment (atmospheric earth surface) or closeenvironment (pipe, channel or tunnel). The system development was carried out in LAGG MiniWindtunnel (LMW), supported by a software builder LABVIEW from National Instrument. Thefollowing paper describes a highlight of velocimetry basic theory, basic concept of software design, andits application to the measurement of flow characteristics.Keywords: turbulence, velocimetry, ultrasonic transducerFariduzzaman; UPT-LAGG BPPT, PUSPIPTEK Serpong, INDONESIA
Read more ....
THE SOLUTION OF MONSTER MATRICES PROBLEMS WITH THE KRYLOVSUBSPACE ITERATION AND THE LANCZOS METHOD
A computational algorithm to solve thespectral problems of monster matrices, i.e. finding the eigenvalues and eigenvectors of real symmetricmatrices N N´ A , with N in the thousands or millions, will be presented below. The Krylov subspaceiteration and the Lanczos methods to be presented below are modern versions that have undergone manyimprovements as reported by Lin & Gubernatis and others.M. Bunjamin; FMIPA-UI dan FMIPA-UNAS
Read more ....
MATHEMATICAL AND NUMERICAL MODEL OF FLUm FLOW IN A PIPE NETWORK BASED ON FEM WITH LEAST ROOT FORMULATION
Mathematical formulationsfor analysis of fluid flow in a pipe network has been studied to be implemented in an appropriatenumerical model. In this case, a numerical model based on Finite Element Method (FEM) has beenchosen. In order to keep the range of applicability as wide as possible, a finite element model has beenderived using the Least Square formulation in place of the frequently used Weighted Residual (Galerkin)formulation. The fluid flow studied here is assumed to be incompressible and steady. Furthermore, thisarticle was limited itself to the development of the numerical model. Hence, further studies, such assolution procedure of the numerical model, are excluded. Ade Jamal, Agus Sainjati, Aris Suwatjono, Lebong Andalaluna; Pusat Pengkajian dan Penerapan Teknologi lnformasi dan Elektronika, BPP Teknologi
Read more ....
DIRECT CONTAINMENT HEATING PHENOMENON IN LWRS
Budi Rohman; Bapeten. Simulation ofdirect containment heating (DCH) phenomenon for B WR 5 Mark II reactor containment vesselhad been performed for the purpose of PSA level 2 study. The accident was assumed to follow asequence with combination of failure on High Pressure Core Spray System and the failure ofmanual depressurization of the reactor coolant system leading to core melt-down. The meltingcore then collapses into the bottom head of the pressure vessel. If the bottom head could notwithstand the increasing thermal and pressure loads released by the melts, it would result in thebreak of the bottom head and subsequent ejection of the core debris to the surface of reactorcavity. During this process, steam containing core debris is then transported to the drywell andcontainment atmosphere as well as to suppression pool where condensation takes place.Various modes of heat transfer, including radiation, conduction, and convection, and masstransfer take place during this process. The release of such a large amount of heat source couldresult in increasing pressure of containment atmosphere. The increase in temperature andpressure loads to the containment could be enhanced by metal-water reaction iftf1.e temperaturereaches the ignition point of this reaction.The simulation assumed release fractions of core debris from reactor vessel to thecavity of 0 %,10 %, 50 %, and 100 %. The temperature and pressure of the containmentatmosphere reach maximum values of 3380 K and 0.726 MPa respectively for the assumedrelease fraction of core debris of 50 %. This pressure is still below the design pressure of thistype of containment, i,e. 0,78 MFa,Kevwords: core melt, BWR 5 Mark-II, containment heating, temperature, pressure.
Read more ....
RADIATION DOSIMETRY AND RADIATION SOURCES
Agnette P. Peralta, M.Sc.; Bureau of Health Devices and Technology (former name: Radiation Health Service) Department of Health, Manila, Philippines The word II radiation II has become a term to fear in our modern world. But what does thisword really mean? Radiation is simply energy transmitted through a distance. There are twotypes of radiation -ionizing and nonionizing radiation. Ionizing radiation (such as x rays andgamma r:ays) causes ionization as it travels through any medium. On the other hand,nonionizing radiation (such as infra-red rays, light, microwaves) does not have sufficientenergy to cause ionization.Ionization is the process whereby an orbital electron acquires sufficient energy to free itselffrom the atom. The remaining positively charged atom is called a positive ion. The removedel~ctron, either alone or when attached to an electrically neutral atom, is called anegative ion.There are two types of ionizing radiation -electromagnetic and particulate.X and gamma rays are forms of ionizing electromagnetic radiation. X rays are produced invacuum tubes when high velocity electrons strike a target. When these electrons arestopped or slowed down by interaction with atoms of materials in their path, x rays areproduced. On the other hand, gamma rays are emitted when nuclei of radioactive atomsdisintegrate or decay.Another type of ionizing radiation is particulate radiation. Any subatomic particle in motion iscapable of producing ionization. And so we can have protons, neutrons, electrons andeven nuclei of atoms as forms of particulate ionizing radiation as long as they possesssufficient energy to ionize matter. Two forms of particulate radiation have special namesalphaand beta radiation. Alpha rays are nuclei of helium atoms. Beta rays are positivelyand negatively charged electrons. Both alpha and beta rays are emitted by radioactivesubstances.In applications of nuclear energy. ionizing radiation is used. Hence, in this paper, the termradiation will be used to mean ionizing radiation
Read more ....
PASSIVE COMPACT MOLTEN SALT REACTOR (PCMSR) UNTUK PRODUKSI HIDROGEN DENGAN BAHAN BAKU AIR LAUT
Andang Widi Harto, Deby Mardiansyah; E-mail: andangftn@yahoo.com.debyfi03@yahoo.com. Penggunaan bahan bakar minyak, batubata dan gas alam pada waktu yang akan datangharns dikurangi karena alasan daya dukung lingkungan dan semakin menipisnyacadangan sumber daya minyak bumi. Permasalahan lingkungan global yang pentingadalah emisi C02 yang dihasilkan oleh penggunaan bahan bakar hidrokarbon (termasukminyak) yang dapat menimbulkan pemanasan global. Oleh karena itu diperlukan bahanbakar alternatif, Diantara bahan bakar alternatif yang sangat potensial adalah bahanbakar hidrogen. Kelebihan bahan .bakar hidrogen adalah ramah lingkungan bila dibanding bahan bakar minyak karena hasil pembakaran dari bahan bakar hidrogen adalah uap air yang tidak menimbulkan' polusi. Hidrogen dapat diproduksi dari air(terutama air laut) yang ketersediaanya sangat melimpah. Permasalahannya adalah. bahwa proses produksi hidrogen dari air merupakan proses padat energi dan menjadilebih efisien jika dilakukan pada suhu tinggi. Diantara berbagai sistem pembangkit dayayang dapat menghasilkan daya dengan intensitas tinggi dan dapat mencapai suhu tinggiyang memenuhi syarat untuk produksi hidrogen adalah reaktor nuklir bersuhu tinggi.Diantara reaktornuklir tersebut, yang cukup memarik untuk dipelajari adalah PassiveCompact Molten Salt Reactor (PCMSR) yang merupakan modifikasi dari Molten SaltReactor (MSR). Jenis reaktor ini dapat mencapai suhu lebih tinggi daripadajenis MSRdan tingkat daya lebih tinggi tetapi tekanan lebih rendah daripada HTR sehingga sesuaiuntuk produksi hidrogen.Kata kunci: PCMSR, suhu tinggi, produksi hidrogen, air laut
Read more ....
Friday, April 25, 2008
NON-LINEAR MODEL FOR WATER DENSITY DATA DEVELOPED AND BASED ON CURVEEXPERT 1.3
Recent development of software makes much contribution in the form of easiness and speed to reach solution of scientific calculation, one of that contribution is in the modelling of observation data. Data of water (H2O) density is reference data which at a glance look like so linear with respecto temperature but using CurveExpert 1.3 there was anevident that some other models which are non-linear have higher level of accuration than the linear model itself. In this paper, using software called CurveExpert 1.3 some non-linear models were presented and can be chosen as anaccurate model based on the criteria that the standard error is close to zero and the coefficient of correlation is close to one. Some models more accurate than the linear model resulting from CurveExpert 1.3 are Gaussian Model, Sinusoidal fit, Weibull Model, Hoerl Model, MMF Model, dan Harris Model. Keywords: density of water, non-linear model, CurveExpert 1.3. Entjie Mochamad Sobbich, Arminda Kastono; Pusat Penelitian KIM-LIPI
Read more ....
ISING MODEL SIMULATION USING DISTRIBUTED PARALLEL COMPUTATION
Ferromagnetic phenomena can be described using ISING model. Using parallel distributed computing, two and three dimensional Ising model simulation is done by the Metropolis Algorithm using PVM parallel programming environment. The parallelization is done geometrically by dividing lattice into small subdomains. We provide numerical parallel system speed-up for variational numbers of processors and lattice sizes. Arief Wicaksono; FMIP A Universitas Indonesia
Read more ....
IMPLEMENTATION OF RUNGE-KUTTA MULTISTEPS IMPLICIT PARALLEL ITERATIVE METHOD ON MPI-LINUX PARALLEL SYSTEM
Scientific code users usually demand fast, accurate and cheap solver. However, this is difficult to fulfill as the requirement is closely related to the methods, algorithm and the environment in which the codes run. Such demands will be more difficult when the problem to be solved become more complex and expensive. With the introduction of parallel computing environments with increasing power, the works on solving of various expensive and difficult phenomena are becoming more widely open and new challenges are appearing. By the invention of such powerful environments it is hoped to solve the numerical problem faster than in the sequential computing environment, to solve insolvable problem with size and time constraints and/or accuracy constraints which were not able be solved in the sequential environment. In this paper, we will discuss the implementation of parallel iterated metode base on variabel stepsize implicit multistep Runge-Kutta of Radau type by using SPMD approach on MPI-Linux parallel system of HPCCSUI Depok Laboratory for stiff problems. Alhadi Bustamam* Heru Suhartanto**, T. Basaruddin**; * Jurusan Matematika FMIPA-UI** Fakultas Ilmu Komputer UI
Read more ....
PERAN AMDAL DALAM SISTEM MANAJEMEM LINGKUNGAN (ISO 14000)
ldris Maxdoni Kamil; Departemen Teknik Lingkungan, ITB. In general, EIA is assumed as one of doc~nts needed to fulfill the requirement for operating an activity. In relation to EMS-ISO 14000, a good and high quality EIA is an asset for preparing and implementing the management system. Recently, some EIA's that have been prepared with low quality. Therefore, an evaluation of methodology of preparation an EIA should be conducted such that the quality can be improved. This paper dcscribes the rclationship between EIA and EMS- ISO 14000 such that the valuc of EIA can be morc appreciatcd.
Read more ....
RX LAPAN ROCKET DATA PROGRAM WITH DBASE III PLUS
The component data rocket RX LAPAN are taken from workshop product and assembling rocket RX. In this application software, the test data are organized into two data files, i.e test file and rocket file. Besides providing facilities to add, edit and delete data, this software provides also data manipulation facility to support analysis and identification of rocket RX failures and success.
Sauman; Pusat Teknologi Wahana Dirgantara - LAPAN
Read more ....
Sauman; Pusat Teknologi Wahana Dirgantara - LAPAN
ANALISIS HUBUNGAN ANTARA DESKRIPTOR, REFERENSI, DAN SITASI UNTUK MEMBANGUN STRUKTUR KOLEKSI DOKUMEN YANG INHEREN
There are many characteristics can be used to identify a document which cover characteristics of the documents, cited documents, and citing documents This research explored the inherent structure of a document collection as one of main components of information retrieval system. The characteristics examined are: descriptors, references (cited documents), and citations (citing documents). Three independent variables were studied: co-descriptor, bibliographic coupling, and co-citation. A test collection was constructed by searching on a single descriptor "information retrieval" in the CD-ROM version of Education Resource Information Clearinghouse (ERIC), covering the period 1981 through 1985. Descriptors were extracted from ERIC; cited and citing documents associated with the test collection were derived from Social Sciences Citation Index (SSCI), covering the period 1981 through 1990. Three hypothesis were tested in this study, that are: (1) the higher the frequency of co-descriptors between documents, the higher the frequencies of their bibliographic coupling and co-citation; (2) the higher the frequency of bibliographic coupling between documents, the higher the frequencies of their co-citation and co-descriptors; and (3) the higher the frequency of co-citation between documents, the higher the frequencies of their co-descriptors and bibliographic coupling. The results showed that all of three hypothesis are supported statistically and there is a significant linear relationship among the observed variables. It is mean that there is a significant relationship among descriptors, references, and citation, so that it can be used to construct the inherent structure of document collection in order to improve information retrieval system performance. Zainal A. Hasibuan* dan Mustangimah**; * Fakultas Ilmu Komputer, Universitas Indonesia ** Pusat Pengembangan Teknologi Informasi dan Komputasi, Badan Tenaga Nuklir Nasional Unive
Read more ....
SEMIPARAMETIC ESTIMATION ON MULTIVARIAT DENSITY FUNCTIONS
The objectives of this paper are to develop a class of semiparametric estimations and to find an appropriate estimator for this class. The idea is to multiply an initial parametric density estimate with a proposal correction function. We consider this study in the multidimensional case. A new estimator should be particularly useful when either parametric or nonparametric methods have problems. The comparisons with the traditional kernel estimator are presented by some practical examples. Mochamad Sonhaji; Metodologi Statistik, Badan Pusat Statistik (BPS)
Read more ....
SOFTWARE DEVELOPMENT OF SUGAR CANE PLANTATION AND HARVESTING MANAGEMENT
This software is a management system based on database-driven computer software application. It is intended to improve the quality of sugar cane through increased efficiency in managing, harvesting and transporting of sugar cane, as part of a sugar factory operation. The software was developed using the Borland Delphi development platform, with database manipulation using Microsoft Access. The software is intended for Personal Computer with Windows 95 (or later) installed. The application has been tested with acceptable result and can be used in Sragi Sugar Factory’s related activities; namely sugar cane plantation management, harvesting and transporting of sugar cane, payment process and other related administrative processes. Key word : plantation and harvesting management, sugar cane, sugar Benny Bintang*, Erwin Yudhana**; * Sentra Teknologi Polimer, BPPT** Direktorat Teknologi Alat dan Mesin Industri, BPPT
Read more ....
DESIGN STUDY OF FAST REACTOR WITH PB-BI COOLING SYSTEM AND ACTINIDE RECYCLE
A design study of fast reactor with Pb-Bi cooling system and actinide recycle has been done. The reactor consists of five regions. The first, the second, the third, the fourth and the fifth regions are respectively the blanket, the main core, the core, the reflector and the shielding. The fisrt region consists of natural uranium, where as the second and the third regions consists of enriched plutonium. The reactor cooling system is of Pb-Bi liquid. Actinide elements obtained are recycled as fuel source in the main core. The actinide elements are Neptunium (Np), Plutonium (Pu), Americium (Am) and Curium (Cu). During recycle burn up process, analysis of multiplication factor change (keff), breeding ration change, peak power density change and mass fraction composition of each actinide element have been carried out. From the result of simulation program calculation written with fortran 77, it is concluded that the fast reactor design developed has a good performance with respect to actinide element recycle. Mohammad Taufik; Fisika FMIPA UNPAD.
Read more ....
AN E-LEARNING PROGRAMMING METHOD AND IT’S IMPLEMENTATION BASED ON MULTIMEDIA AND WEB
New developments in information technology and telecommunication play an important rile in exchanging fast and accurate information which range from text, sound, graphic to video. These technologies seem to be very effective for Distance learning, Virtual University and Elearning. This paper presents an E-learning programming method and it’s implementation based on multimedia and Web. An example of the study case corresponds to human organ, where the organ functions are presented as texts and sounds and the activities as graphic and video. Sarifuddin Madenda, Tommy F. R.; Universitas Gunadarma, Email : sarif@staff.gunadarma.ac.id
Read more ....
POSITRON EMISSION TOMOGRAPHY
Jr. Wiiono Hadikusumo; PT. Dian Graha Elektrika, Jakarta. Positron Emission Tomography atau disingkat PET adalah suatu modalitas pembentukan gambar irisan tubuh manusia, yang mirip dengan X-ray CT scanner dan MRI, Damon berdasarkan prinsip yang berbeda. PET yang prinsip keIjanya mirip SPECT Damon dengan banyak kelebihan, telah mulai dirintis dalam bidang research pacta awal tahun 70-an, kini telah berkembang menjadi suatu metoda klinis yang banyak dipakai di berbagai negara, sebagai pelengkap dari x-ray CT scanner maupun MRI, karena kalau CT dan MRI menghasilkan gambar irisan anatomis, PET mampu memberikan gambar irisanfisiologis. Pada permulaannya salah satu kendala bagi perkembangan PET adalah kenyataan bahwa radioisotop yang dipakai dalam PET pacta umumnya berumur sangat singkat, oksigen-15 misalnya berumur paro hanya 2,1 meDii, sehingga praktis diperlukan sebuah somber radioisotop, dalam hal ini sebuah cyclotron, di tempat pemeriksaan, atau tempat pemeriksaan didirikan ditempat dimana sudah terdapat sebuah cyclotron. Dengan perkembangan teknologi yang pesat, anatara lain dengan telah diproduksinya mini cyclotron yang khusus menghasilkan radioisotop untuk keperluan PET, maka kendala tersebut kini telah dapat teratasi.
Read more ....
MATHEMATICAL AND NUMERICAL MODEL OF FLUM FLOW IN A PIPE NETWORK BASED ON FEM WITH LEAST ROOT FORMULATION
Mathematical formulations for analysis of fluid flow in a pipe network has been studied to be implemented in an appropriate numerical model. In this case, a numerical model based on Finite Element Method (FEM) has been chosen. In order to keep the range of applicability as wide as possible, a finite element model has been derived using the Least Square formulation in place of the frequently used Weighted Residual (Galerkin) formulation. The fluid flow studied here is assumed to be incompressible and steady. Furthermore, this article was limited itself to the development of the numerical model. Hence, further studies, such as solution procedure of the numerical model, are excluded. Ade Jamal, Agus Sainjati, Aris Suwatjono, Lebong Andalaluna; Pusat Pengkajian dan Penerapan Teknologi lnformasi dan Elektronika, BPP Teknologi
Read more ....
Novel Active Disturbance Rejection Control of Self-Sensing Magnetic Bearings for Flywheel Energy Storage
A linearized model of a self-sensing magnetic bearing used in a flywheel energy storage application is analyzed and an intrinsic feedback mechanism is identified. Based on the model, a cascaded-loop controller is designed using a novel control design technique which actively rejects external disturbances, taking advantage of the feedback mechanism. Simulation results of force-disturbance rejection performance are presented. B. X. S. Alexander, Richard Rarick, Lili Dong
Read more ....
Wednesday, April 23, 2008
PERANCANGAN PROGRAM APLIKASI PENGENALAN WAJAH
PERANCANGAN PROGRAM APLIKASI PENGENALAN W AJAHBERBASISKAN JARINGAN SY ARAF TIRUAN DENGANMENERAPKAN METODE PRINCIPAL COMPONENT ANALYSI. Information concerning someone at present is very important and difficult to get if there are a lotof data of people. One of techniques to get information concerning someone is from his or her photo,where from the photo of the face will be got someone's identity, which later will give the informationabout him or her. Many people have tried and succeeded to build a face recognition application programby various methods where each method has its superiority and deficiency. There is a fast method inrecognition face image but sacrificing its accuracy of recognition, so is the contrary. The purpose of thisresearch is to design and build a face recognition application program for computer by utilizing principalcomponent analysis which has artificail neural network bases. In this research, the writers made a facerecognition program from object of the form face image, side detection until we got the imagecharacteristics and came up with its recognition process with artificial neural network. The writers builtand tested the program in a laboratory. After a testing was conducted, we obtain the result of analysis that the program could recognize most faces tested. Several failures occurred because the program has adifficulty in recognizing similar faces.Keywords: Face recognition, Principal Component Analysis, Artificial Neural Network.Wikaria Gazali clan Lily; Universitas Bina Nusantara
Read more ....
ISING MODEL SIMULATION USING DISTRIBUTED PARALLEL COMPUTATION
Ferromagnetic phenomena can be described using ISING model. Using parallel distributed computing,two and three dimensional Ising model simulation is done by the Metropolis Algorithm using PVMparallel programming environment. The parallelization is done geometrically by dividing lattice intosmall subdomains. We provide numerical parallel system speed-up for variational numbers of processorsand lattice sizes.Arief Wicaksono; FMIP A Universitas Indonesia
Read more ....
THE PREDICTION OF THE INSTANTANEOUS MESH STIFFNESS OF SPUR GEARS AND THE INFLUENCE OF MISALIGNMENT ERRORS AND LONGITUDINAL TOOTH CORRECTIONS
The magnitude and the vibration of gear mesh stiffness affect tooth loading and gear dynamics significantly. In fact, the variation of mesh stiffness is considered as an important source of excitation for gear systems. This paper describes the use of a 3D finite element model for the prediction of instantaneous mesh stiffness of a spur gear and for the analysis of the stress distributions at the tooth root for misaligned gears. This paper also discusses the use of longitudinal corrections (parabolic crowning) for the improvement of stress distributions at tooth root for misaligned gears. The described method and the corresponding results present a contribution for the improvement of existing calculations in gear dynamic excitationsM. MAATAR, S. ZOUARI, C. KARRA; Laboratory of Electro-Mechanical Systems (LASEM)
Read more ....
DAMAGE IDENTIFICATION IN STRUCTURAL MEMBERS WITH VARIABLE THICKNESS USING GENETIC ALGORITHM
Tapered structural members such as beams are very important in various engineering applications. Movable arms, towers and antennae are the most typical examples that can be generalised as a beam with variable thickness. A minor damage on any part of these structures reduces the strength of the structure and leads to a major failure. In this paper, a new formulation of an objective function for the genetic search optimization procedure along with the residual force method is presented for the identification of macroscopic structural damage in a tapered beam. The developed model requires experimentally determined data as input and detects the location and extent of the damage in the beam. Here, numerically simulated data using finite element models of structures are used to identify the damage at a reasonable level of accuracy. Damage parameters given theoretically are compared by the present procedure and are found to be in good agreement. S.K. Panigrahi, S. Chakraverty, B.K. MishraKEYWORDSDamage, Genetic Algorithm (GA), Residual Force, Objective Function, Eigen Value, tapered cantilever beam
Read more ....
Monday, April 21, 2008
SAFETY ANALYSIS OF ACTINIDE RECYCLED FAST POWER REACTOR
Simulation for safety analysis of actinide recycled fast power reactor has been performed. The objective is to know reactor response about ULOF and ULOF & UTOP simultaneous accident. From parameter result such reactivity feedback, power, temperature, and cooled flow rate can conclusion that reactor have inherent safety system, which can back to new Equilibrium State.
Mohammad Taufik; Lab. Fisika Energi, Jurusan Fisika, FMIPA, Universitas Padjadjaran
Read more ....
Mohammad Taufik; Lab. Fisika Energi, Jurusan Fisika, FMIPA, Universitas Padjadjaran
UTILIZATION OF WAVELET TRANSFORMATION FOR REMOTE SENSING IMAGE
Usually radar SAR imagery has so very much noise and speckel that reduce the user interpretation accuracy. There are many filter types created special to improve radar SAR imageries, however, people do not be satisfied with them. Therefore one do experiments of wavelet transformation utilization as filters to improve radar imagery. Several outcomes were compared to get which one is the best. Mohammad Natsir*, Wiweka**; * Peneliti pada Unit Komduk Pusat Teknologi Penginderaan Jauh LAPAN** Peneliti pada Bidang Pengolahan Data Pusat Teknologi Penginderaan Jauh LAPAN
Read more ....
Multistep Runge-Kutta Methods for solving DAEs
Several methods have been used by some authors to solve Differential Algebraic Equations (DAEs), the methods range from multistep methods such as BDF and EBDF methods to one-step methods such as Runge-Kutta methods. In this paper, we present Multistep Runge-Kutta methods (MRKs) for solving DAEs which are the extension of our previous works for solving ODEs. We discuss fixed stepsize MRKs and Variable Coefficient MRKs. The methods treat the DAEs as problems of the form M y' = f(x). We implement the MRKs in parallel iteration technique and present some numerical tests. Keywords: DAEs, Multistep Runge Kutta Methods, Variable Coefficient, Parallel Iteration Technique
Read more ....
JARINGAN KOMPUTASI
Bidang Computational Science berkembang dengan pesat seiring dengan perkembangan teknologi komputer kinerja tinggi ( High Performance Computing-HPC), sehingga membuka dimensi baru dalam perkembangan dunia riset dan rekayasa/rancang bangun dan pemodelan fenomena alam melalui pendekatan model matematika. Kemampuan dalam bidang Computational Science & Engineering sangat diperlukan oleh Indonesia untuk mengantisipasi persaingan global, mengingat setiap industri maju selalu memerlukan teknologi HPC untuk rancangan produk dan proses inovatif sehingga waktu yang diperlukan dalam pengembangan konsep produk sampai pemasaran dapat dikurangi secara radikal. Di sisi lain jaringan berkembang sebagai suatu media untuk suatu perubahan sosial, menciptakan peluang baru pada pasar informasi dan konektivitas, dan memperluas batasan untuk kegiatan penelitian dan pengembangan dari segi waktu dan ruang. Ilmu pengetahuan dan informasi adalah sumberdaya yang strategis pada saat ini dan abad mendatang : Pengaksesan terhadap sumberdaya ini melalui jaringan elektronik adalah sangat vital untuk suatu negara seperti Indonesia, yang secara geographis sangat besar dan terdiri dari ribuan pulau. Dalam makalah ini saya ingin sedikit mengulas tentang perkembangan dunia komputasi dan jaringan komputer yang membentuk suatu konvergensi sehingga mendorong berkembangnya computational network. Ashwin Sasongko; Deputi Kepala Bidang Teknologi Informasi, Energi, Material dan Lingkungan – BPP Teknologi
Read more ....
A NONLINEAR-WAVE PHENOMENON: SOLITONS
The natural nonlinear-wave phenomena of solitons are presented through their mathematical models known as Korteweg-de Vries and sine-Gordon equations. The Burgers equation and shock-waves as a special case of Korteweg-de Vries equation is also briefly mentioned. Computational solutions using finite difference method are also presented. M. Bunjamin*; FMIPA Univ. Indonesia & Univ. Nasional
Read more ....
THE CALCULATION OF TITANIUM BUILDUP FACTOR BASED ON MONTE
The objective of radioactive-waste container is to reduce radiation emission to the environment. For that purpose, we need material with ability to shield that radiation and last for 10.000 years. Titanium is one of the materials that can be used to make containers. Unfortunately, its buildup factor, which is an importance factor in setting up radiation shielding, has not been calculated. Therefore, the calculations of titanium buildup factor as a function of other parameters is needed. Buildup factor can be determined either experimentally or by simulation. The purpose of this study is to determine titanium buildup factor using simulation program based on Monte Carlo method. Monte Carlo is a stochastic method, therefore is proper to calculate nuclear radiation which naturally has random characteristic. Simulation program also able to give result while experiments can not be performed, because of their limitations.The result of the simulation is, that by increasing titanium thickness the buildup factor number and dosage increase. In contrary If photon energy is higher, then buildup factor number and dosage are lower. The photon energy used in the simulation was ranged from 0.2 MeV to 2.0 MeV with 0.2 MeV step size, while the thickness was ranged from 0.2 cm to 3.0 cm with step size of 0.2 cm. The highest buildup factor number is b = 1.4540 ± 0.047229 at 0.2 MeV photon energy with titanium thickness of 3.0 cm. The lowest is b = 1.0123 ± 0.000650 at 2.0 MeV photon energy with 0.2 cm thickness of titanium. For the dosage buildup factor, the highest dose is bD = 1.3991 ± 0.013999 at 0.2 MeV of the photon energy with a titanium thickness of 3.0 cm and the lowest is bD = 1.0042 ± 0.000597 at 2.0 MeV with titanium thickness of 0.2 cm. For the photon energy and the thickness of titanium used in simulation, buildup factor and dosage buildup factor as a function of photon energy and titanium thickness can be formulated as follow b = 1.1264 e – 0.0855 E e 0.0584 T, and bD = 1.0961 e – 0.0722 E e 0.0336 T. Hengky Istianto Has*Balza Achmad **, Andang Widi Harto**.; * Sarjana Teknik Nuklir, Fakultas Teknik, Universitas Gadjah Mada** Dosen Jurusan Teknik Nuklir, Fakultas Teknik, Universitas Gadjah Mada
Read more ....
DEVELOPMENT OF ADVANCED NUCLEAR ENERGY SYSTEMS IN INDIA
To ensure long term availability of nuclear energy in a sustainable manner, taking cognisance of its resource position, India has followed the closed fuel cycle and chalked out a three-stage nuclear power programme based on uranium and thorium. The three stages of this programme comprise: (1) Natural uranium fuelled Pressurised Heavy Water Reactors, (2) Fast breeder reactors utilising plutonium based fuel, (3) Advanced nuclear power systems for utilization of thorium. PHWR technology has already reached maturity. The second stage of Indian nuclear power programme aims at setting up of Fast Breeder Reactors for power production and fissile material multiplication. The second stage has started with setting up of a Fast Breeder Test Reactor (FBTR) to understand and master the fast reactor technology. The experience gained in fast reactor technology has led to the development of 500 MWe Prototype Fast Breeder Reactor, the construction of which is going on. The third stage of the Indian nuclear power programme envisages setting up of advanced nuclear power systems based on Thorium-U233 cycle. At present development work is going on the following advanced systems: (1) Advanced Heavy Water Reactor (AHWR); (2) Compact High Temperature Reactor; (3) Multipurpose Nuclear Power Pack; (4) High Temperature Reactor (HTR) for Hydrogen Production. The paper will focus on the salient design features of these advanced systems. Development of Advanced Nuclear Energy Systems in India P.D. Krishnani Email: pdkrish@barc.gov.in Reactor Physics Design Division Bhabha Atomic Research Centre, Trombay, Mumbai - 400 085, INDIA
Read more ....
MODERN TRENDS OF COMPUTATION, SIMULATION, & COMMUNICATION, ...
SIMULATION, & COMMUNICATION, AND THEIR IMPACTS ON THE PROGRESS OF SIENTIFIC AND ENGINEERING RESEARCH, DEVELOPMENT, AND EDUCATION A short report on the modern trends of computation, simulation, and com-munication in the 1990s is presented, along with their impacts on the progress of scientific & engineering research, development, and education. A full description of this giant issue is certainly a “mission impossible” for the author. Nevertheless, it is the author’s hope that it will at least give an overall view about what is going on in this very dynamic field in the advanced countries. After “thinking globally” thru reading this report, we should then decide on “what & how to act locally” to respond to these global trends. The main source of information reported here were the computational science & engineering journals & books issued during the 1990s as listed in the references below. M. Bunjamin; FMIPA – Univ. Indonesia & Univ. Nasional,
Read more ....
Studi NORM Dan TENORM Dari Kegiatan Industri Non Nuklir
BIRM and TENORM now become topics for discussion among experts of radioactive wastes. This paper describes the status of the management of NORM and TENORM waste including their origin, regulations and disposal assessment. Some advanced countries have established the regulations for NORM and TENORM waste. However the IAEA has not yet published any guideline for the managemen of NORM and TENORM. There are many options for disposal of NORM and TENOR. There are many options for disposal of NORM and TENORM waste based on standard radioactive waste storage/disposal procedures. The decision and policy on the management of NORM and TENORM waste must be mode carefully in account of the social and economical impacts. Djarot S. Wisnubroto-Batan
Read more ....
Simultaneous selection of beam directions for treatment planning and for image reconstruction
Dose verification in radiotherapy needs daily imaging of the patient so the anatomic or position changes can be seen which may suggest replanning before the next treatment. Using standard equipment, it is not possible to obtain the daily image while the patient is on the treatment couch. The patient has to be moved to the CT scanning to obtain the daily image, which is not so practical. In addition, information from many angles for the daily image, as is required with a complete CT scanner, cannot be easily obtained due to time constraints. One possible solution to obtain the daily image would be to collect limited information while the patient is on the treatment couch. In other words, the angles for treatment planning and for imaging have to be the same. Thus, this research aims to establish a method to solve this problem. This approach uses a combination of coplanar beam positions for treatment planning of prostate cancer. A small number of beams (7 and 9) were used to explore the solution space to determine the best beam positions. The beam directions obtained for the prostate case compared well with standard criteria. The average optimization quality factors, the projection correlation values, and the dose-volume histograms were analyzed for this case. This also used two optimization methods, the gradient descent method and the simulated annealing. This process greatly reduced the overall computation time for clinical routine. The combination of treatment planning optimization and imaging optimization using projection correlation method provides the basis for powerful tools that assists the radiotherapy planner in achieving the ultimate goal: finding the treatment plan that is the best R. Widita1, L.C. Holloway2 1Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Bandung 40132, Indonesia. 2Department of Radiation Oncology, Liverpool Hospital, Liverpool, NSW, Australia
Read more ....
ECONOMIC DESIGN OF CONTROL CHART AT PT XYZ.
Control chart nowadays can be used not only for monitoring activity but also for performance measurement, forecasting, maintenance, and others. Economic design of control chart represents one method to analyze control chart. The method determines control chart with its economic value from cost value during monitoring activity when it takes place. The Economic comparison could be used to determine optimal parameter like amount of sample, specification of correct standard, and minimum total expenses. PT XYZ is a manufacturing industry, which produces commercial vehicle of XXX. It takes place in industial area of Pulo Gadung. To be survive among competitors, the company should pay more attention to quality which conformance to consumers. This research designs control chart for company by considering the actual condition that happened at the company. Total expected cost value of control chart equals to Rp. 4.939.841,15 per cycle, or equals to Rp. 148.193,27 per period. Then searched considering of that total cost to find optimal solution which give lower expense. The result of calculation got three alternatives of optimal solution. The three solutions is chosen later by examination using three analysis. Through the analysis, it will be able to get one optimal solution which most conducive and earn as according to requirement of company. At this research is also enhanced economic design of control chart when company apply six-sigma concept. Keywords: Statistical Quality Control, Economic Design of Control Chart, Automotive Spare-part Sidiky Achmad K dan Betrianis; Departemen Teknik Industri, Fakultas Teknik Universitas Indonesia, Kampus Baru UI Depok, Jawa Barat 16424, Email : betrianis@ie.ui.ac.id ; sidikyachmadkarim00@ie.ui.ac.id
Read more ....
Karakterisasi Limbah Batubara Kalimantan Timur
The characterization of wasted coal resulted from coal mining activity in East Kalimantan island has been carried out order to know its physical and chemical properties such as particle size distribution, mineral impurities, calorific value, ash content, volatile matter content, fixed carbon and moisture content. The characteristic of wasted coal constitutes the basic data as basis to decide the best utilization to be chosen to yield more added value. Rustiadi Purawiardi-LIPI
Read more ....
Thursday, April 10, 2008
Practical aspects which affect an electrical measurement
This paper focuses on some of the practical considerations for electrical measurement. Though these are not measurement techniques but have a very significant effect on precision measurement. Some of these are leakage currents, thermal effects, contact resistance, transients, grounding, shielding, earthing, guarding and drift. The precision measurement depends on control of all these important but sometimes subtle factors. K B Ravat & S K Mahajan
Read more ....
Thermoelastic analysis of a laminated composite skew plate with a circular cutout subjected to linearly varying temperature across the thickness
The behaviour of a laminated composite skew plate with hole subjected to temperature as well as combined temperature and transverse pressure loading has been investigated. A finite element method which works on the basis of three-dimensional theory of elasticity is employed to evaluate the transverse deflection, in-plane stresses and interlaminar stresses. The results obtained by varying the skew angle and the hole diameter are discussed. It has been observed that the magnitude of the stresses and deflection in case of combined loading is more when compared with the respective values in case of pure thermal loading. The magnitudes of the transverse deflection and in-plane stresses for combined loading are observed to be less at higher skew angles, because the distance between opposite sides of the plate decreases with increase in skew angle causing for increase in the stiffness of the plate. The solutions of skew structures considered in the present analysis will be useful for the construction of safe and efficient structures like skew bridges and swept wings of aircraft structures.A V Sudhakar, K Mohana Rao & V Ramachandra Raju
Read more ....
Development of potassium-selective ion-sensitive field-effect transistor (ISFET)
(ISFET) by depositing ionophoric crown ether membrane on the gate dielectric, and its application to the determination of K+-ion concentrations in blood serum. This paper reports the fabrication and characterization of potassium ISFET (ion-sensitive field-effect transistor) by deposition of a crown ether layer on the gate. This ISFET is referred to as potassium MEMFET (membrane field-effect transistor) or potassium-selective MEMFET device. Calibration of ISFET in standard KCl solutions has shown that the sensitivity of crown ether-ISFET towards potassium (2.3 mV/mg/L) was approximately double that of the nitride-gate ISFET (1 mV/mg/L) in the 100-400 mg/L range. The mechanism of ISFET potassium sensitivity enhancement by the ionophoric crown ether layer on the gate has been explained. Use of the device for potassium concentration measurements in human blood serum has been demonstrated. The distribution of potassium ion concentrations (151-210 mg/L) in a series of human blood serum samples has been determined from the reference value obtained by atomic absorption spectroscopy and the ISFET sensitivity measured with KCl solutions. These diluted samples showed a constant pH ~ 7.0-7.1, confirming the maintenance of pH within close tolerance by the human body; therefore any errors due to pH variation amongst the samples were eliminated. Sensitivity of the ISFET with/without crown ether coating on the gate towards sodium ions (0.34 mV/mg/L) has been found to be comparatively less than that of the crown ether ISFET for potassium, showing that sodium ions in blood serum do not interfere with the measurements. V K Khanna, S Ahmad, Y K Jain, M Jayalakshmi, S Vanaja, S S Madhavendra,s v Manorama & M Lakshmi Kantam
Read more ....
Drying shrinkage of cementitious composites with mineral admixtures
This paper emphasises on the influence of mineral admixtures (MA) like silica fume, metakaoline and fly ash on the drying shrinkage of cement mortars incorporated with MA as cement replacement material. MA has been varied at different percentages from 0 to 15% at the constant increment of 5%. The water-binder (cement + MA) ratio and binder-sand ratios are 0.5 and 1:3 respectively. The short-term and long-term ultimate drying shrinkage of mortar has been studied. The effect of size of sand particles has been studied with different sizes of particles fractions. The highest drying shrinkage has been observed in mortars with higher silica fume contents at the age of 28 days. At the early ages, this has been due to the high pozzolanic reaction of silica fume, as a result of pore-size refinement mechanism of silica fume. However, the effect of silica fume has not been significant on the long-term drying shrinkage. The effect of grain size demonstrates that the ultimate drying shrinkage decreases as the size of sand particles increases. R Malathy & K Subramanian
Read more ....
Determination of fracture parameters of concrete based on water-cement ratio
The aim of this study is to predict formulas based on the Abrams’ Law between fracture parameters of concrete and w/c. Therefore, a series of three-point bend test on specimens were performed. The beams were made from mixes with water/cement ratios varying in the range of 0.34-0.85. The fracture parameters for each mix were calculated according to a popular fracture mechanics approach — two-parameter model. The present experimental data indicate that the fracture parameters of two-parameter model are inversely proportional to w/c ratios. In conclusion, the present test results are in agreement with the Abrams’ Law. Ragip Ince & Kürsat Esat Alyamaç
Read more ....
Effect of cement and EPS beads ratios on compressive strength and density of lightweight concrete
The compressive strengths and slump values of concretes made up of mixtures of expanded polystyrene (EPS) beads and cement were investigated. To determine the effect of Portland cement (PC)/EPS ratio, on the compressive strength of EPS concrete, 1/0 (control sample), 1:4, 1:2, 3:4 and 1:1 mix proportion by volume were used. EPS beads content for the mixtures were kept constant at 0.05 m3. The analysis of the test results leads to the conclusion that with the increase of cement to EPS beads ratio in the mixes, both density and compressive strength of concretes increased up to 4 and 350 times respectively, when compared to the control sample. Hardened concrete densities and compressive strength varied from 464 to 1940 kg/m3, and 0.11 to 38.50 MPa, respectively. Slump values of the mixes were changed from 8 to 43 mm. Abdulkadir Kan & Ramazan Demirboga
Read more ....
Optimization of die angle and ram velocity for rod extrusion using dynamic material modeling and genetic algorithm
Selection of processing and geometrical parameters is a crucial step in the extrusion process design. Optimized parameters may result in desirable microstructure at minimum load. To achieve this goal, dynamic material modeling (DMM) and genetic algorithms (GA) are used in this study. Selection of strain rate and temperature is done by DMM which insures dynamic recrystalization (DRX) zone during processing. Minimization of punch load is formulated as a nonlinear programming problem which is solved using GA to result in optimum ram velocity and die angle. Two rod extrusion processes are successfully optimized using proposed approach. K K Pathak & N Ramakrishnan
Read more ....
On the derivation of the symmetric and asymmetric Hele–Shaw flow equations for viscous and viscoplastic fluids using the viscometric fluidity function
In viscometric flows, the viscometric fluidity function is used to define the shear rate as a function of the shear stress. This relationship is unique even if the viscosity function is constant or has a plateau. As far as a viscoplastic fluid is concerned, the viscometric function is zero when the magnitude of the shear stress is below the yield stress and is positive when the fluid has yielded. Using this fluidity function and integration by parts, it is quite simple to integrate the equations of motion defining a Hele–Shaw flow in viscous and viscoplastic fluids for both symmetric and asymmetric flow conditions. From this, the average velocity field is derived in a manner which is superior to those based on the viscosity–shear rate relationship, especially since such a relation is not invertible in all cases. R.R. Huilgol
Read more ....
High stress abrasive wear behaviour of shot peened AA2014 Al-alloy
AA2014 Al alloy specimens (in the form of plates) have been shot peened to varying intensity levels (0.14 to 0.48 mm ALMEN ‘N’) and the effect of shot peening intensity on the subsurface plastic deformation, surface and subsurface residual stress field, depth of peening and microstructure evolution has been investigated. The influence of shot peening intensity on the high stress abrasive wear behaviour has also been investigated. The wear rate reduced significantly due to mild shot peening. Intensive shot peening did not lead to any significant improvement in wear resistance, rather beyond a critical peening intensity, the wear resistance of material starts deteriorating. D P Mondal, E M Vinod, S Das & T S V C Rao
Read more ....
Investigation of the low temperature performances of polymer and fiber modified asphalt mixtures
In this study, effects of polymer and fiber modification on low temperature properties of bituminous mixtures were studied. One aggregate, one asphalt binder type, three additives (polymer, synthetic fiber and loose cellulose fiber) and three 85°C oven aging levels (0, 5 and 25 days) were considered. The thermal stress restrained specimen test (TSRST) was used to evaluate the low temperature cracking resistance and aging performance of modified asphalt concrete specimens. The analysis of covariance was performed using a general linear model (GLM) procedure on the TSRST results by using statistical analysis system (SAS) software. Aging levels and type of additive were determined as most important factors that affect fracture temperature and fracture strength. Fracture temperature becomes warmer with the increase in the degree of aging. It was observed that fracture temperature and fracture strength change according to additive type used. Yuksel Tasdemir & Emine Agar
Read more ....
Properties of adhesive joint of inorganic nano-filler composite adhesive
The characteristics of adhesive joints of aluminium sheet containing epoxy based composite adhesives containing nano-filler of ZrO2 powder have been studied. The composite adhesives containing 10, 15 and 20wt.% of about 20±3 nm size ZrO2 powder are applied to mechanically treated aluminium substrates. The single lap joints of the composite adhesive are characterized by their tensile lap shear strength as a function of the bond-line thickness as well as the amount of filler. The characteristics of the composite adhesive joint have been compared to those of the conventional epoxy adhesive joints. The bond-line thickness of the adhesive with respect to the amount of the ZrO2 nano-filler has been optimised for maximum tensile single lap shear strength of the adhesive joint of mechanically treated aluminium substrate. In comparison to conventional epoxy adhesive joints, the nano-filler epoxy based adhesive joint of aluminium shows significantly improved lap shear strength as a function of bond line thickness of adhesive and amount of filler in it. (P K Ghosh & S K Nukala)
Read more ....
A Hybrid Method for Moving Interface Problems with Application to the Hele–Shaw Flow
In this paper, a hybrid approach which combines theimmersed interface methodwith thelevel set approachis presented. The fast version of the immersed interface method is used to solve the differential equations whose solutions and their derivatives may be discontinuous across the interfaces due to the discontinuity of the coefficients or/and singular sources along the interfaces. The moving interfaces then are updated using the newly developed fast level set formulation which involves computation only inside some small tubes containing the interfaces. This method combines the advantage of the two approaches and gives a second-order Eulerian discretization for interface problems. Several key steps in the implementation are addressed in detail. This new approach is then applied to Hele–Shaw flow, an unstable flow involving two fluids with very different viscosity. Thomas Y. Hou, Zhilin Li, Stanley Osher and Hongkai Zhao
Read more ....
Large deflection analysis of rhombic sandwich plates placed on elastic foundation
This paper presents non-linear analysis of rhombic sandwich plates placed on elastic foundation under uniform load. Banerjee’s hypothesis1 involving a new form of energy expression in the total potential energy of the system has been employed. As a consequence the differential equation is decoupled keeping intact its non-linear character. The aim of the present study is to analyze the non-linear behaviour of rhombic sandwich plates placed on elastic foundation for different skew angles. The results have been obtained both for movable and immovable edges from a single cubic equation. Numerical results (central deflection versus load) have been computed and compared with known results (K=0) for square sandwich plates only. The corresponding linear analysis (K=0) is also presented. The results thus obtained are in good agreement with those repoted in the literature. Gora Chand Chell, Subrata Mondal & Goutam Bairagi
Read more ....
Synthesis and characterization of Mn doped PZT ceramics
In the present work, the effect of Mn doped PZT ceramics with composition Pb(Zr0.52Ti0.48)O3 + x wt.% of MnO2, (where x =0, 1, 2 and 3) has been reported. The samples are prepared by employing a simple co-precipitation technique using nitrates of lead, zirconium and titanium isopropoxide. X-ray diffraction studies confirm the formation of pure phase and homogeneous ceramics of tetragonal symmetry. Scanning electron micrographs shows a uniform grain distribution and the grain size and shape are modified upon Mn addition. Increase in Mn content causes a decrease in average grain size of the material. Dielectric measurements demonstrate a decrease in the dielectric constant and increase in dielectric loss with increase in Mn. The dielectric dispersion is large for the higher concentration of Mn ions in PZT at lower frequencies and is attributed to the space charge accumulation. The undoped and Mn doped PZT ceramics exhibit the hysteresis loops which confirms the ferroelectric behaviour. The prepared ceramics have very low dielectric loss, high dielectric constant and high transition temperature which may be useful for device application. K L Yadav & Pallavi Sharma
Read more ....
Seismic behaviour of cylindrical elevated tanks with a frame supporting
The seismic responses of an elevated tank with a frame supporting system on various subsoils are investigated. The finite element method is used for the modelling of the elevated tank and subsoil system. Fixed-base and elastic media assumptions are made for subsoil. The tank fluid has been modelled as lumped masses such as impulsive and convective masses proposed by Housner. An added mass approach is used for fluid-structure interaction by representing both the impulsive mass and the convective mass. For estimating the seismic response of elevated tanks, response spectrum analysis with mode superposition is used. The results obtained from modelling the elevated tanks on a fixed base and on an elastic medium are compared. It has been observed that the seismic response of the elevated tank is altered significantly depending on the properties of the subsoil. The soil-structure interaction especially affects the impulsive modes and lateral displacement of elevated tanks rather than the torsional modes. It is proposed that the coupling effect for perpendicular directions in the axisymmetrical plan geometry should be considered in the seismic design of the elevated tanks. Ramazan Livaoglu & Adem Dogangun
Read more ....
Dynamic permanent deformation testing of asphalt mixes and deformation waveform analysis
In this study, different specimens of hot mix asphalt (HMA) have been constructed in the laboratory and tested under repeated loading; first permanent deformation and later fatigue tests using Suleyman Demirel University Asphalt Tester equipment (SDU-Asphalt Tester). This study reports evaluation of available information about relationship between permanent deformation and fatigue cracking. Analysis of data shows that the fatigue life of the pavement may be modelled in terms of data obtained from repeated loading axial permanent deformation test results. Based on the analysis of the estimation model for fatigue life from permanent deformation testing, it is concluded that for the evaluation of HMA in fatigue characterization, repeated load axial test for permanent testing can be used in a very satisfactory manner. To be able to model the fatigue lives, in addition to conventional fatigue model parameters new parameters from repeated load permanent deformation test are taken into consideration. Hence, only by examining the permanent deformation tests, it may be possible to predict the fatigue lives of the specimens without carrying out time-consuming fatigue tests. Mesut Tigdemir
Read more ....
Computation of Axisymmetric Suction Flow through Porous Media in the Presence of Surface Tension
The effect of small surface tension on a class of axisymmetric flows with suction is studied numerically. The dynamic evolution of a blob of incompressible viscous fluid, surrounded by air and drawn into an interior sink, is considered.The velocity field of the viscous fluid is assumed to satisfy Darcy's law and thus the motion is that of a flow through porous media. The fluid interface motion is computed using a highly accurate boundary integral method. This method combines recent numerical techniques to achieve efficient and high-order space and time discretizations for this type of flow. Through accurate computations, it is shown that, in the presence of small surface tension, the dynamic behavior of the axisymmetric flows is very similar to that of the (two-dimensional) Hele–Shaw counterparts. A long finger develops in the fluid interface and forms a cone singularity when it reaches the sink before all the fluid is sucked out. The finger bulges and develops a neck for sufficiently small surface tension. The bulge–neck formation is enhanced by the additional component of the mean curvature in the three-dimensional flow. However, its effect is not strong enough to cause the interface to pinch off at the neck for the data considered here. Hector D. Ceniceros and Helen Si.
Read more ....
Penyalahgunaan mikroorganisme dalam kesejahteraan manusia
Pendahuluan : Tahun-tahun terakhir abad 20 dan awal abad baru, abad 21, beberapa negara di planetini mendapat berbagai ancaman terorisme. Terorisme yang dilakukan oleh sekelompok masyarakat/ orang yang ingin melaksanakan kehendak dengan berbagai bentuk ancaman baik fisik, mental, maupun tindakan kekerasan berupa perusakan, perbuatan kriminal (aksi peledakan bom), penyebaran penyakit bahkan pembunuhan. Tindakan semacam ini dapat dilakukan dengan mengatasnamakan kepentingan tertentu baik politik, ekonomi atau kepentingan kekuasaan lainnya untuk mendapatkan tanggapan yang diinginkan. Tidak jarang mereka melakukan tindakan teror dengan menggunakan berbagai alat atau senjata yang dapat mengakibatkan kerugian, cidera atau kerusakan dalam jumlah banyak, baik terhadap segala bentuk fasilitas kegiatan masyarakat umum dan penyakit pada hewan serta pertanian maupun kematian manusia. Ancaman terorisme yang marak dalam dekade terakhir ini seringkali dikaitkan dengan penggunaan agen hayati (mikroorganisme) sebagai sumber/penyebab penyakit yang mematikan, yang sering dikenal dengan bioterorisme. Pada dekade yang sama Indonesia menghadapi persoalan teror, kerusuhan dan tindakan anarkhis marak di mana-mana, terjadi penculikan, pemboman dan pembunuhan, bahkan sampai kini belum diketahui dimana dan apa alasan yang benar terjadinya kasus kasus itu. Aksi teror baik yang berakibat kerusakan bangunan fisik maupun benda lainnya dan kematian manusia di seluruh pelosok nusantara, oleh provokator kerusuhan maupun pelaku utamanya. Tidak luput dari gerakan teror di dalam negeri, di berbagai manca negara seperti Amerika Serikat, Jepang dan negara-negara Eropah lainnya telah banyak didengar berita mengenai terorisme. Tambahan, terkait dengan aksi terorisme internasional, ketika Menara Kembar World Trade Center di NewYork dan Gedung Markas Besar Pertahanan USA Pentagon pada tanggal 11 September 2001 pagi waktu setempat dengan selang beberapa menit ditabrak oleh tiga pesawat komersial yang berakibat kerugian fisik material sangat besar dan jatuhnya moral/martabat negara adidaya yang tak dapat dinilai.
Sesungguhnya terorisme dengan menggunakan senjata gas, racun hasil metabolit mikroorganisme atau tumbuhan dan bahan kimia lainnya telah lama dilarang dalam peperangan, misalnya pada zaman Yunani atau Romawi kuno dan bangsa India sekitar 500 SM. Peperangan nutfah (germ) bukanlah ancaman baru dan akan menggantikan perang nuklir (konvensional), tetapi dengan perkembangan ilmu pengetahuan mikrobiologi khususnya persenjataan nutfah makin mendapat perhatian besar yang lebih canggih dan menakutkan. Hal ini karena kemampuan membunuhnya lebih efektif daripada bentuk persenjataan api atau nuklir, juga tanpa adanya kemungkinan pengelolaan dan profilaksis lanjut. Meskipun demikian pelarangan menggunakan persenjataan kimiawi dan hayati itu telah disepakati dalam perjanjian internasional yang pertama dalam Protokol Jenewa, 1925, dan kedua pada Konvensi Persenjataan Biologi 1972 yang melarang tidak hanya penggunaan tetapi pengembangan, produksi, dan penimbunan/persediaannya. Pada kesepakatan internasional ketiga, Konvensi Persenjataan Kimiawi, 1993, mempertegas negara-negara mana yang menuruti perjanjian persenjataan itu dan memberi sanksi bagi yang melanggar. Dalam kaitan ini, tujuan penulisan kaji-pustaka ini akan menguraikan tentang beberapa bentuk penyalahgunaan peran mikroorganisme di dalam lingkungan, kesehatan dan dalam memenuhi kebutuhan manusia untuk meningkatkan kesejahteraan hidup dengan lebih menekankan pada penyalahgunaan fungsi mikroorganisme yang tidak sepatutnya, bioterorisme. Peran Mikroorganisme dalam Lingkungan - KesehatanPeran penting mikrobiologi pertama kali diperkenalkan dalam karya karya Louis Pasteur, Robert Koch, Winogradsky dan lainnya yang menjadi terkenal dengan “Era Emas Mikrobiologi”, (1870-1910). Selama era ini tidak hanya sebagian besar bakteri agen-penyebab penyakit pada manusia telah diidentifikasi, tetapi juga peran mikroorganisme sebagai pendaur-ulang sebagian besar unsur- hara penting kehidupan organisme di bumi telah diketahui. Pertengahan pertama abad 20 para ahli (mikrobiologiwan) banyak mengkonsentrasikan pada identifikasi bakteri (mikroba) dan upaya-upaya perawatan penyakit yang kemungkinan disebabkan oleh jasad renik. Teknik kultur murni (monokultur) mikroba telah dikembangkan oleh Robert Koch, yang bermanfaat untuk mempelajari sifat patogen dan mengkaji interaksinya dalam lingkungan alami yang heterogen. Perkembangan bioteknologi selama paruh akhir abad 20, kemudian dipacu ledakan perkembangan biologi molekuler, memberikan kontribusi keberhasilan perkembangan DNA rekombinan, yang mempunyai banyak peran dalam penggunaannya di lingkungan. Peran mikrobiologi lain yang menarik bagi manusia diantaranya fungsi dalam ekosistem alami sangat berdayaguna memberi kontribusi dalam perombakan dan perbaikan senyawa-senyawa kimiawi pencemar , kontaminan bahkan senyawa xenobiotik yang sangat sulit dirombak dan persisten (recalcitrant). Kemampuan ini secara alami sangat lambat dalam jangka waktu lama, makin kompleks senyawa kimiawi sintetik dan berbeda jauh dengan struktur senyawa kimia alam, makin kompleks makin sulit dan diperlukan waktu lama bagi mikroba untuk menyesuaikan pertumbuhannya dengan habitat barunya. Usaha-usaha pengembangan fungsi mikroba untuk meningkatkan daya perombakan dan perbaikan bahan-bahan kimia pencemar sering dikenal dengan bioremediasi. Berbalikan dengan kepentingan Bioterorisme, keduanya sama-sama memanfaatkan kemampuan metabolisme mikroba di alam dengan berbagai perlakuan uji-coba berulang dan teknologi yang canggih didukung perkembangan bioteknologi genetika dan biomolekuler dalam laboratorium, Bioremediasi sekarang mendapat perhatian yang makin besar dari para mikrobiologiwan untuk meningkatkan kesejahteran alam hidup manusia. Perkembangan teknologi untuk memanfaatkan peran mikroorganisme maksimum di alam makin bertambah dan makin membuka wacana baru dalam pengelolaan perannya guna mendukung dan meningkatkan dayadukung lingkungan planet ini untuk tetap lestari dan berkelanjutan.Di pihak lain perkembangan pengetahuan mengenai genetika mikroorganisme ini lebih berkembang akan tetapi masih sedikit diketahui mengenai ekologi mikroba yang berkaitan dengan kelangsungan hidup, kompetisi, pertumbuhan, fungsi dan keamanannya di lingkungan alami. Berkaitan dengan aspek kesehatan beberapa faktor yang bertanggungjawab terhadap timbulnya patogen baru adalah:1)perpindahan populasi penduduk (demografi/urbanisasi) dan perilaku 2)teknologi dan industri3)perkembangan ekonomi dan tataguna lahan4)perjalanan dan perdagangan internasional5)adaptasi dan perubahan mikroba6)penurunan kualitas kesehatan masyarakat7)kejadian alam yang abnormal yang menaikkan keseimbangan patogen-inang biasa dan akhirnya8)situasi lain yang mengancam pemaparan jumlah banyak penyakit mapan maupun baru yang mungkin terjadi dalam peperangan hayati. Beberapa contoh hanya mewakili sedikit cara-cara mikroorganisme dan virus yang dimanfaatkan untuk meningkatkan kesejahteraan manusia, meski pada masa lalu mikroorganisme hanya dianggap sebagai organisme berbahaya karena dapat menimbulkan penyakit. Penyakit virus smallpox (cacar) telah diketahui merupakan salah satu pembunuh terbesar dunia. Lebih kurang 4000 tahun lampau diperkirakan 10 juta orang mati karena penyakit ini. Beberapa tahun terakhir ini tidak lahi ditemukan kasus penyakit ini setelah program faksinasi di seluruh dunia telah berhasil dilakukan sejak 1977. Penyakit yang menjadi pembunuh besar lainnya adalah wabah pes (bubonic plague). Hampir sepertiga seluruh populasi daratan Eropa, kurang lebih 25 juta orang antara tahun 1346 dan 1350 mati karena penyakit yang disebabkan oleh bakteri, tetai kini rata- rata kuran dari 100 orang per tahun di seluruh dunia yang meninggal akibat wabah ini. Setidaknya ada 500.000 spesies mikroba di alam, dan mungkin lebih banyak lagi tetapi hanya beberapa ratus spesies saja yang berpotensi sebagai patogen pada manusia. Banyak mikroorganisme melakukan aktivitasnya secara bebas yang esensial mendukung kehidupan, dan banyak lain yang erat berhubungan dengan tumbuhan dan hewan yang stabil dan hubungan bermanfaat. Akan tetapi pada spesies yang patogen mempunyai efek sangat negatif terhadap organissme inangnya dan akibatnya seringkali banyak menjadi obyek kajian para pemegang kekuasaan kejahatan. Beberapa dekade waktu pada abad pertengahan wabah penyakit telah menyerang populasi bangsa Eropah. Wabah epidemi kuno datang berasal dari adanya pergantian populasi tikus dalam tengah kota dan dipengaruhi misalnya oleh variabel-variabel seperti cuaca dan hasil panenan. Kini kita mempunyai pusat wabah baru yang dapat menyerang kota-kota . Akan tetapi wabah baru itu tidak dipengaruhi oleh gejala alam, tetapi agaknya wabah ini dipengaruhi oleh variabel-variabel modern seperti: keinginan politik, ekonomik dan militer. Wabah baru ini merupakan perang biologi yakni penggunaan organisme hayati agen-agen melukai atau membunuh tentara atau populasi penduduk dalam suatu tindakan perang atau terorisme. Propagasi massa hayati dan Bioterorisme Pada masa yang bersamaan pengembangan keamanan mikroba di lingkungan menjadi bagian besar perhatian untuk maksud-maksud perdamaian dan pertahanan keamanan suatu negara, sebaliknya erat berkaitan dengan kemampuan mikroba sebagai sarana persenjataan perang, yang dikenal dengan senjata biologi (hayati), atau sering dikonotasikan dengan senjata pembunuh massa. Persenjataan biologi mendapat perhatian sejumlah kalangan pada akhir-akhir ini karena berkaitan dengan kemudahan pembuatan dan propagasi massa hayati (mikroba) tidak saja oleh ahli biologi/mikrobiologiwan semata tetapi juga mereka yang berpengalaman dalam kerja laboratorium propagasi sel (kultur jaringan). Keahlian demikian diketahui atau dicurigai mendapat pasokan dana atau menjadi alat kekuasaan beberapa pejabat atau rejim pemerintahan dan kelompok radikal/ekstrimis untuk mendukung misi atau untuk penggunaan terorisme. Walaupun kenyataan bahwa senjata biologi sangat bermanfaat dalam penanganan kekuatan militer biasa, kemungkinan terbesar penggunaan senjata biologi boleh jadi oleh kelompok terorist ini merupakan bagian dari para mikrobiologiwan yang terlatih dengan ketrampilan laboratorik tinggi. Ada organisasi bahkan negara sedang berkembang yang sangat miskin atau kelompok politik yang sangat ekstrim dapat membutuhkan keuangan sangat besar menguasai keahlian teknis untuk memeperoleh dan menggunakan senjata biologik. Jadi agen-agen ini berpotensi merusak massa yang terselubung yang ekivalen dengan bom atom oleh orang-orang di negara maju. Adanya bakteri patogen dan atau virus yang sangat bermanfaat untuk “perang hayati” dan banyak anggotanya sangat mudah untuk memperolehnya, mengembangbiakannya dan menyebarluaskannya. Mikroorganisme yang sangat umum menjadi agen-agen tersebut dapat disebutkan sebagaiu berikut:1) Bacillus anthraxis agen penyebab anthrax. Oleh karena B. anthraxis menghasilkan endospora yang bila disemprotkan akan dapat menyebar luas sangat efektif Bakteri patogen melalui inhalasi berupa bentuk spora atau bakteri hidup dan menyebabkan infeksi paru-paru dengan laju mortalitas hampir 100 persen. Pencegahan terhadap penyakit ini dapat dilakukan dengan vaksinasi, namun jarang tersedia vaksin, meskipun tidak terjadi penjalaran melalui persentuhan. Endospora Baccillus ini telah lama digunakana untuk “senjata hayati”, karena mudah diperoleh, yang bersifat endemik pada ternak dan hampir di seluruh dunia. Mudah memproduksi spora dalam jumlah besar dan bertahan lama kemampuan hasil daya-toksisnya. Seringkali bioterorisme dikaitkan dengan spora Bacillus anthraxis , dan Paul Keim, 2001, ahli dalam identifikasi strain anthrax, telah menyimpan koleksi strain sebanyak 1300 dari seluruh dunia. Dengan teknik identifikasi yang memfokuskan pada sejumlah variasi ulangan tandem dan spot pada genom mikroba ini. Spora ini telah digunakan semenjak Perang Dunia I dan selama “ perang dingin” Ameriak Serikat dan Uni Soviet masih melanjutkan pengembangan program persenjataan hayati ini secara- besar-besaran yang melibatkan ribuan orang, teknik yang lebih canggih dan penyempurnaan daam penyediaan secara cepat maupun penyampaian kepada sasaran yang dikenai. Spesies lain yang menghasilkan bentuk endospora dan sangat resisten adalah 2) Clostridium botullinum. Calon yang lebih eksoktik adalah agen yang berupa racun botulinum yang dihasilkan bakteri ini. Racun yang bersifar aerosol meskipun membran mukus dapat menyerap racun ini, tapi dapat digunakan sebagai “senjata hayati”. Botulisme ini dapat dicegah dengan vaksinasi, tapi seringkali tidak tersedia, tetapi antitoksin banyak tersedia dan tidak bersiat menular 3) Virus Smallpox juga menjadi calon untuk “persenjataan hayati”, walaupun vaksin smallpox (cacar) yang sangat efektif, belum digunakan secara teratur selama lebih dari 20 tahun karena smallpox telah diberantas di seluruh dunia pada 1980. Akibatnya lebih dari 90% populasi penduduk dunia kini kurang mendapat vaksin yang memadai dan mudah terjangkit penyakit ini.. Virus ini sejak diketahui tok sisitasnya dijadualkan untuk dirusak pada 1999 dan dapat diperkirakan bahwa agen ini secara tetap berpotensi.menjadi daftar calon “senjata hayati”. Penyakit variola ini telah diketahui merupakan salah satu pembunuh terbesar dunia. Lebih kurang 4000 tahun lampau diperkirakan 10 juta orang mati karena penyakit ini. Penyakit yang menjadi pembunuh besar lainnya adalah wabah pes (bubonic plague),.4) Yersinia pestis; mikroorganisme yang bertanggungjawab selama wabah pandemik abad pertengahan, itu Hampir sepertiga seluruh populasi daratan Eropah, kurang lebih 25 juta orang antara tahun 1346 dan 1350 mati karena penyakit yang disebabkan oleh bakteri ini. Pentingnya cara penjalaran penyakit ini oleh kutu yang hidup pada hewan mengerat yang menggigit seseorang dan kemudian terinfeksi Yersinia pestis, karenanya penyakit wabah pes ini masih berpotensi disalahgunakan sebagai calon “senjata hayati”. Bakteri membelah berlipatganda dengan cepat dalam nodus limfa, tetapi tidak menular dan memiliki laju mortalitas 50 – 75%. Beberapa calon mikroorganisme yang dapat digunakan sebagai “senjata hayati” lainnya misalnya: 5) Salmonella typhi (penyakit-penyakit melalui makanan atau media air) dan tergantung dari jumlah minimum tertentu patogen dalam tubuh untuk menyebabkan gejala sakit. Salmonellosis yang disebabkan oleh bakteri jenis ini, rata-rata 47.500 kasus per tahun dijumpai di Amerika Serikat. Gejala penyakit ini umumnya dikenal dengan demam tiphus, yaitu diarhae, mual-mual, muntah dan demam tergantung dari virulensi strain Salmonella..6) Francisella tularensis (demam kelinci) penyebab tularemia, dan 7) Brucella abortus (demam dan bacterimia), keduanya mampu menyebabkan infeksi fatal.8) Virus Rabies dan 9) virus Ebola. Banyak diantara agen-agen yang menyebabkan penyakit selama beberapa hari atau minggu pemaparan dengan laju kematian yang tinggi. Suatu sifat umum agen pembawa penyakit yang dapat disebarluaskan adalah dalam bentuk aerosol yang mudah menyebar luas serta menginfeksi secara sederhana dan cepat, Pada 1962., terjadi satu ledakan smallpox (cacar) lalu di negara-negara maju terjadi di Jerman.. Penyakit ini menginfeksi para pekerja Jerman sepulang dari Pakistan, terkena wabah cacar yang segera berkembang dan dirawat serta dikarantinakan.. Oleh karena batuk pasien tersebut, berakibat menginfeksi 19 orang menjadi tervaksinasi, setidaknya satu orang meninggal dunia,. Pada kassus lain di Sverdlovs Rusia, sekurangnya satu gram spora telah menyebar ke atmosfer dari fasilitas persenjataan, dan setiap orang disekitar area itu terimunisasi dan diberikan terapi antibiotik profilaksis segera setelah kasus anthrax pertama kali diketahui. Sekitar 77 orang di luar fasilitas itu terjangkit anthrax sedang 66 individu lainnya mati. Pada tahun 1984 ekstrimis keagamaan di USA menginokulasi Salmonella dalam salad di 10 kedai makanan, yang telah menyebabkan 751 kasus salmonellosis makanan terjadi di daerah yang biasanya hanya 10 %.Kabar terakhir Lembaga Genetika di Tashkent, Uzbekistan 1996 telah mengungkapkan hasil penelitiannya mengenai jenis jamur (fungi) yang menyerang sistem perakaran tanaman pertanian sebangsa opium poppies. Lembaga yang didukung oleh Dinas Militer Uni soviet ini pada masa itu ditugaskan sebagai pusat pengkajian peran mikroorganisme perusak tanaman pertanian. Pertanian opium merupakan tanaman penghasil bahan narkotika yang cukup tinggi nilai ekonominya, oleh karenanya seorang ahli penyakit tanaman berkevbangsaan Inggris Paul Rogers menyatakan adanya bukti baru penggunaan “senjata hayati” terhadap tanaman pertanian. Dampak penyalahgunaan peran mikroorganismePenyalahgunaan peran mikroorganisme untuk kegiatan yang merugikan seperti halnya bioterorisme ini berdampak sangat luas. Pengawasan dan kewaspadaan terhadap bahaya bioterorisme yang harus selalu ditingkatkan dengan berbagai upaya pengembangan sidik-cepat dan upaya penanggulangannya merupakan kajian yang memerlukan biaya operasi cukup besar. Negara adidaya Amerika Serikat misalnya dalam tahun anggaran belanja 2002 harus menjatahkan dana sebesar lebih kurang 1.500. juta dolar. Dampak penyalahgunaan peran ini sangat meluas baik dari segi politik maupun ekonomi, keamanan, kesehatan dan bahkan peradaban suatu bangsa. Pemberlakuan hukum dalam rangka antisipasi keamanan warganegara dan atau undang-undang perdagangan dalam negeri negara adikuasa itu pun terhadap bahaya bioterorisme secara langsung ataupun tidak langsung sangat berpengaruh terhadap pertumbuhan ekonomi negara-negara pengekspor komoditas ke negara maju. Rentetan administrasi dan registrasi yang harus memenuhi baku prasyarat keamanan bahaya bioterorisme itu berakibat penambahan prosedur dan beban ekonomi yang tidak saja makin berbelit dan biaya tinggi juga waktu dan tahap penyesuaian yang berlarut. Ironinya banyak dugaan dan ataupun isu yang berkembang asal muasal bioterorisme tidak lepas dari kondisi sosekpolkam negara berkembang dan kekhawatiran negara maju yang berlebihan..Di lain pihak akhir-akhir ini digalakkan lagi pembuatan vaksinasi besar-besaran guna mengantisipasi aksi ini. engan pemberian vaksinasi dimungkinkan seseorang mengalami kekebalan permanen terhadap penyakit yang ditimbulkan spesies yang sama, meski sampai saat ini lebih kurang seperempat abad lalu penyakit ini dinyatakan telah musnah, misalnya penyakit cacar (variola). KesimpulanMikroorgansime sebagai bagian struktur biotik dalam ekosistem maupun biosfer memiliki peran besar dalam kehidupan umat manusia di planet bumi ini, yang berfungsi unik, sebagai pengurai atau dekomposer dalam tingkatan trofik ekosistem yang seringkali sangat bermanfaat bagi keberlanjutan kehidupan dan kesejahteraan umat manusia. Namun di pihak lain mikroorganisme dapat berakibat merusak dan kehancuran sendi-sendi kehidupan umat manusia itu sendiri bilamana manusia tidak dapat mengendalikannya ataupun diri manusia itu sendiri.Bentuk penyalahgunaan peran mikroorganisme yang tidak sepatutnya seperti bioterorisme, dan sebaliknya yang seharusnya untuk kemaslahatan umat manusia, dapat berdampak sangat luas memasuki sendi-sendi kehidupan manusia. Oleh Edwi Mahajoeno
Read more ....
Sesungguhnya terorisme dengan menggunakan senjata gas, racun hasil metabolit mikroorganisme atau tumbuhan dan bahan kimia lainnya telah lama dilarang dalam peperangan, misalnya pada zaman Yunani atau Romawi kuno dan bangsa India sekitar 500 SM. Peperangan nutfah (germ) bukanlah ancaman baru dan akan menggantikan perang nuklir (konvensional), tetapi dengan perkembangan ilmu pengetahuan mikrobiologi khususnya persenjataan nutfah makin mendapat perhatian besar yang lebih canggih dan menakutkan. Hal ini karena kemampuan membunuhnya lebih efektif daripada bentuk persenjataan api atau nuklir, juga tanpa adanya kemungkinan pengelolaan dan profilaksis lanjut. Meskipun demikian pelarangan menggunakan persenjataan kimiawi dan hayati itu telah disepakati dalam perjanjian internasional yang pertama dalam Protokol Jenewa, 1925, dan kedua pada Konvensi Persenjataan Biologi 1972 yang melarang tidak hanya penggunaan tetapi pengembangan, produksi, dan penimbunan/persediaannya. Pada kesepakatan internasional ketiga, Konvensi Persenjataan Kimiawi, 1993, mempertegas negara-negara mana yang menuruti perjanjian persenjataan itu dan memberi sanksi bagi yang melanggar. Dalam kaitan ini, tujuan penulisan kaji-pustaka ini akan menguraikan tentang beberapa bentuk penyalahgunaan peran mikroorganisme di dalam lingkungan, kesehatan dan dalam memenuhi kebutuhan manusia untuk meningkatkan kesejahteraan hidup dengan lebih menekankan pada penyalahgunaan fungsi mikroorganisme yang tidak sepatutnya, bioterorisme. Peran Mikroorganisme dalam Lingkungan - KesehatanPeran penting mikrobiologi pertama kali diperkenalkan dalam karya karya Louis Pasteur, Robert Koch, Winogradsky dan lainnya yang menjadi terkenal dengan “Era Emas Mikrobiologi”, (1870-1910). Selama era ini tidak hanya sebagian besar bakteri agen-penyebab penyakit pada manusia telah diidentifikasi, tetapi juga peran mikroorganisme sebagai pendaur-ulang sebagian besar unsur- hara penting kehidupan organisme di bumi telah diketahui. Pertengahan pertama abad 20 para ahli (mikrobiologiwan) banyak mengkonsentrasikan pada identifikasi bakteri (mikroba) dan upaya-upaya perawatan penyakit yang kemungkinan disebabkan oleh jasad renik. Teknik kultur murni (monokultur) mikroba telah dikembangkan oleh Robert Koch, yang bermanfaat untuk mempelajari sifat patogen dan mengkaji interaksinya dalam lingkungan alami yang heterogen. Perkembangan bioteknologi selama paruh akhir abad 20, kemudian dipacu ledakan perkembangan biologi molekuler, memberikan kontribusi keberhasilan perkembangan DNA rekombinan, yang mempunyai banyak peran dalam penggunaannya di lingkungan. Peran mikrobiologi lain yang menarik bagi manusia diantaranya fungsi dalam ekosistem alami sangat berdayaguna memberi kontribusi dalam perombakan dan perbaikan senyawa-senyawa kimiawi pencemar , kontaminan bahkan senyawa xenobiotik yang sangat sulit dirombak dan persisten (recalcitrant). Kemampuan ini secara alami sangat lambat dalam jangka waktu lama, makin kompleks senyawa kimiawi sintetik dan berbeda jauh dengan struktur senyawa kimia alam, makin kompleks makin sulit dan diperlukan waktu lama bagi mikroba untuk menyesuaikan pertumbuhannya dengan habitat barunya. Usaha-usaha pengembangan fungsi mikroba untuk meningkatkan daya perombakan dan perbaikan bahan-bahan kimia pencemar sering dikenal dengan bioremediasi. Berbalikan dengan kepentingan Bioterorisme, keduanya sama-sama memanfaatkan kemampuan metabolisme mikroba di alam dengan berbagai perlakuan uji-coba berulang dan teknologi yang canggih didukung perkembangan bioteknologi genetika dan biomolekuler dalam laboratorium, Bioremediasi sekarang mendapat perhatian yang makin besar dari para mikrobiologiwan untuk meningkatkan kesejahteran alam hidup manusia. Perkembangan teknologi untuk memanfaatkan peran mikroorganisme maksimum di alam makin bertambah dan makin membuka wacana baru dalam pengelolaan perannya guna mendukung dan meningkatkan dayadukung lingkungan planet ini untuk tetap lestari dan berkelanjutan.Di pihak lain perkembangan pengetahuan mengenai genetika mikroorganisme ini lebih berkembang akan tetapi masih sedikit diketahui mengenai ekologi mikroba yang berkaitan dengan kelangsungan hidup, kompetisi, pertumbuhan, fungsi dan keamanannya di lingkungan alami. Berkaitan dengan aspek kesehatan beberapa faktor yang bertanggungjawab terhadap timbulnya patogen baru adalah:1)perpindahan populasi penduduk (demografi/urbanisasi) dan perilaku 2)teknologi dan industri3)perkembangan ekonomi dan tataguna lahan4)perjalanan dan perdagangan internasional5)adaptasi dan perubahan mikroba6)penurunan kualitas kesehatan masyarakat7)kejadian alam yang abnormal yang menaikkan keseimbangan patogen-inang biasa dan akhirnya8)situasi lain yang mengancam pemaparan jumlah banyak penyakit mapan maupun baru yang mungkin terjadi dalam peperangan hayati. Beberapa contoh hanya mewakili sedikit cara-cara mikroorganisme dan virus yang dimanfaatkan untuk meningkatkan kesejahteraan manusia, meski pada masa lalu mikroorganisme hanya dianggap sebagai organisme berbahaya karena dapat menimbulkan penyakit. Penyakit virus smallpox (cacar) telah diketahui merupakan salah satu pembunuh terbesar dunia. Lebih kurang 4000 tahun lampau diperkirakan 10 juta orang mati karena penyakit ini. Beberapa tahun terakhir ini tidak lahi ditemukan kasus penyakit ini setelah program faksinasi di seluruh dunia telah berhasil dilakukan sejak 1977. Penyakit yang menjadi pembunuh besar lainnya adalah wabah pes (bubonic plague). Hampir sepertiga seluruh populasi daratan Eropa, kurang lebih 25 juta orang antara tahun 1346 dan 1350 mati karena penyakit yang disebabkan oleh bakteri, tetai kini rata- rata kuran dari 100 orang per tahun di seluruh dunia yang meninggal akibat wabah ini. Setidaknya ada 500.000 spesies mikroba di alam, dan mungkin lebih banyak lagi tetapi hanya beberapa ratus spesies saja yang berpotensi sebagai patogen pada manusia. Banyak mikroorganisme melakukan aktivitasnya secara bebas yang esensial mendukung kehidupan, dan banyak lain yang erat berhubungan dengan tumbuhan dan hewan yang stabil dan hubungan bermanfaat. Akan tetapi pada spesies yang patogen mempunyai efek sangat negatif terhadap organissme inangnya dan akibatnya seringkali banyak menjadi obyek kajian para pemegang kekuasaan kejahatan. Beberapa dekade waktu pada abad pertengahan wabah penyakit telah menyerang populasi bangsa Eropah. Wabah epidemi kuno datang berasal dari adanya pergantian populasi tikus dalam tengah kota dan dipengaruhi misalnya oleh variabel-variabel seperti cuaca dan hasil panenan. Kini kita mempunyai pusat wabah baru yang dapat menyerang kota-kota . Akan tetapi wabah baru itu tidak dipengaruhi oleh gejala alam, tetapi agaknya wabah ini dipengaruhi oleh variabel-variabel modern seperti: keinginan politik, ekonomik dan militer. Wabah baru ini merupakan perang biologi yakni penggunaan organisme hayati agen-agen melukai atau membunuh tentara atau populasi penduduk dalam suatu tindakan perang atau terorisme. Propagasi massa hayati dan Bioterorisme Pada masa yang bersamaan pengembangan keamanan mikroba di lingkungan menjadi bagian besar perhatian untuk maksud-maksud perdamaian dan pertahanan keamanan suatu negara, sebaliknya erat berkaitan dengan kemampuan mikroba sebagai sarana persenjataan perang, yang dikenal dengan senjata biologi (hayati), atau sering dikonotasikan dengan senjata pembunuh massa. Persenjataan biologi mendapat perhatian sejumlah kalangan pada akhir-akhir ini karena berkaitan dengan kemudahan pembuatan dan propagasi massa hayati (mikroba) tidak saja oleh ahli biologi/mikrobiologiwan semata tetapi juga mereka yang berpengalaman dalam kerja laboratorium propagasi sel (kultur jaringan). Keahlian demikian diketahui atau dicurigai mendapat pasokan dana atau menjadi alat kekuasaan beberapa pejabat atau rejim pemerintahan dan kelompok radikal/ekstrimis untuk mendukung misi atau untuk penggunaan terorisme. Walaupun kenyataan bahwa senjata biologi sangat bermanfaat dalam penanganan kekuatan militer biasa, kemungkinan terbesar penggunaan senjata biologi boleh jadi oleh kelompok terorist ini merupakan bagian dari para mikrobiologiwan yang terlatih dengan ketrampilan laboratorik tinggi. Ada organisasi bahkan negara sedang berkembang yang sangat miskin atau kelompok politik yang sangat ekstrim dapat membutuhkan keuangan sangat besar menguasai keahlian teknis untuk memeperoleh dan menggunakan senjata biologik. Jadi agen-agen ini berpotensi merusak massa yang terselubung yang ekivalen dengan bom atom oleh orang-orang di negara maju. Adanya bakteri patogen dan atau virus yang sangat bermanfaat untuk “perang hayati” dan banyak anggotanya sangat mudah untuk memperolehnya, mengembangbiakannya dan menyebarluaskannya. Mikroorganisme yang sangat umum menjadi agen-agen tersebut dapat disebutkan sebagaiu berikut:1) Bacillus anthraxis agen penyebab anthrax. Oleh karena B. anthraxis menghasilkan endospora yang bila disemprotkan akan dapat menyebar luas sangat efektif Bakteri patogen melalui inhalasi berupa bentuk spora atau bakteri hidup dan menyebabkan infeksi paru-paru dengan laju mortalitas hampir 100 persen. Pencegahan terhadap penyakit ini dapat dilakukan dengan vaksinasi, namun jarang tersedia vaksin, meskipun tidak terjadi penjalaran melalui persentuhan. Endospora Baccillus ini telah lama digunakana untuk “senjata hayati”, karena mudah diperoleh, yang bersifat endemik pada ternak dan hampir di seluruh dunia. Mudah memproduksi spora dalam jumlah besar dan bertahan lama kemampuan hasil daya-toksisnya. Seringkali bioterorisme dikaitkan dengan spora Bacillus anthraxis , dan Paul Keim, 2001, ahli dalam identifikasi strain anthrax, telah menyimpan koleksi strain sebanyak 1300 dari seluruh dunia. Dengan teknik identifikasi yang memfokuskan pada sejumlah variasi ulangan tandem dan spot pada genom mikroba ini. Spora ini telah digunakan semenjak Perang Dunia I dan selama “ perang dingin” Ameriak Serikat dan Uni Soviet masih melanjutkan pengembangan program persenjataan hayati ini secara- besar-besaran yang melibatkan ribuan orang, teknik yang lebih canggih dan penyempurnaan daam penyediaan secara cepat maupun penyampaian kepada sasaran yang dikenai. Spesies lain yang menghasilkan bentuk endospora dan sangat resisten adalah 2) Clostridium botullinum. Calon yang lebih eksoktik adalah agen yang berupa racun botulinum yang dihasilkan bakteri ini. Racun yang bersifar aerosol meskipun membran mukus dapat menyerap racun ini, tapi dapat digunakan sebagai “senjata hayati”. Botulisme ini dapat dicegah dengan vaksinasi, tapi seringkali tidak tersedia, tetapi antitoksin banyak tersedia dan tidak bersiat menular 3) Virus Smallpox juga menjadi calon untuk “persenjataan hayati”, walaupun vaksin smallpox (cacar) yang sangat efektif, belum digunakan secara teratur selama lebih dari 20 tahun karena smallpox telah diberantas di seluruh dunia pada 1980. Akibatnya lebih dari 90% populasi penduduk dunia kini kurang mendapat vaksin yang memadai dan mudah terjangkit penyakit ini.. Virus ini sejak diketahui tok sisitasnya dijadualkan untuk dirusak pada 1999 dan dapat diperkirakan bahwa agen ini secara tetap berpotensi.menjadi daftar calon “senjata hayati”. Penyakit variola ini telah diketahui merupakan salah satu pembunuh terbesar dunia. Lebih kurang 4000 tahun lampau diperkirakan 10 juta orang mati karena penyakit ini. Penyakit yang menjadi pembunuh besar lainnya adalah wabah pes (bubonic plague),.4) Yersinia pestis; mikroorganisme yang bertanggungjawab selama wabah pandemik abad pertengahan, itu Hampir sepertiga seluruh populasi daratan Eropah, kurang lebih 25 juta orang antara tahun 1346 dan 1350 mati karena penyakit yang disebabkan oleh bakteri ini. Pentingnya cara penjalaran penyakit ini oleh kutu yang hidup pada hewan mengerat yang menggigit seseorang dan kemudian terinfeksi Yersinia pestis, karenanya penyakit wabah pes ini masih berpotensi disalahgunakan sebagai calon “senjata hayati”. Bakteri membelah berlipatganda dengan cepat dalam nodus limfa, tetapi tidak menular dan memiliki laju mortalitas 50 – 75%. Beberapa calon mikroorganisme yang dapat digunakan sebagai “senjata hayati” lainnya misalnya: 5) Salmonella typhi (penyakit-penyakit melalui makanan atau media air) dan tergantung dari jumlah minimum tertentu patogen dalam tubuh untuk menyebabkan gejala sakit. Salmonellosis yang disebabkan oleh bakteri jenis ini, rata-rata 47.500 kasus per tahun dijumpai di Amerika Serikat. Gejala penyakit ini umumnya dikenal dengan demam tiphus, yaitu diarhae, mual-mual, muntah dan demam tergantung dari virulensi strain Salmonella..6) Francisella tularensis (demam kelinci) penyebab tularemia, dan 7) Brucella abortus (demam dan bacterimia), keduanya mampu menyebabkan infeksi fatal.8) Virus Rabies dan 9) virus Ebola. Banyak diantara agen-agen yang menyebabkan penyakit selama beberapa hari atau minggu pemaparan dengan laju kematian yang tinggi. Suatu sifat umum agen pembawa penyakit yang dapat disebarluaskan adalah dalam bentuk aerosol yang mudah menyebar luas serta menginfeksi secara sederhana dan cepat, Pada 1962., terjadi satu ledakan smallpox (cacar) lalu di negara-negara maju terjadi di Jerman.. Penyakit ini menginfeksi para pekerja Jerman sepulang dari Pakistan, terkena wabah cacar yang segera berkembang dan dirawat serta dikarantinakan.. Oleh karena batuk pasien tersebut, berakibat menginfeksi 19 orang menjadi tervaksinasi, setidaknya satu orang meninggal dunia,. Pada kassus lain di Sverdlovs Rusia, sekurangnya satu gram spora telah menyebar ke atmosfer dari fasilitas persenjataan, dan setiap orang disekitar area itu terimunisasi dan diberikan terapi antibiotik profilaksis segera setelah kasus anthrax pertama kali diketahui. Sekitar 77 orang di luar fasilitas itu terjangkit anthrax sedang 66 individu lainnya mati. Pada tahun 1984 ekstrimis keagamaan di USA menginokulasi Salmonella dalam salad di 10 kedai makanan, yang telah menyebabkan 751 kasus salmonellosis makanan terjadi di daerah yang biasanya hanya 10 %.Kabar terakhir Lembaga Genetika di Tashkent, Uzbekistan 1996 telah mengungkapkan hasil penelitiannya mengenai jenis jamur (fungi) yang menyerang sistem perakaran tanaman pertanian sebangsa opium poppies. Lembaga yang didukung oleh Dinas Militer Uni soviet ini pada masa itu ditugaskan sebagai pusat pengkajian peran mikroorganisme perusak tanaman pertanian. Pertanian opium merupakan tanaman penghasil bahan narkotika yang cukup tinggi nilai ekonominya, oleh karenanya seorang ahli penyakit tanaman berkevbangsaan Inggris Paul Rogers menyatakan adanya bukti baru penggunaan “senjata hayati” terhadap tanaman pertanian. Dampak penyalahgunaan peran mikroorganismePenyalahgunaan peran mikroorganisme untuk kegiatan yang merugikan seperti halnya bioterorisme ini berdampak sangat luas. Pengawasan dan kewaspadaan terhadap bahaya bioterorisme yang harus selalu ditingkatkan dengan berbagai upaya pengembangan sidik-cepat dan upaya penanggulangannya merupakan kajian yang memerlukan biaya operasi cukup besar. Negara adidaya Amerika Serikat misalnya dalam tahun anggaran belanja 2002 harus menjatahkan dana sebesar lebih kurang 1.500. juta dolar. Dampak penyalahgunaan peran ini sangat meluas baik dari segi politik maupun ekonomi, keamanan, kesehatan dan bahkan peradaban suatu bangsa. Pemberlakuan hukum dalam rangka antisipasi keamanan warganegara dan atau undang-undang perdagangan dalam negeri negara adikuasa itu pun terhadap bahaya bioterorisme secara langsung ataupun tidak langsung sangat berpengaruh terhadap pertumbuhan ekonomi negara-negara pengekspor komoditas ke negara maju. Rentetan administrasi dan registrasi yang harus memenuhi baku prasyarat keamanan bahaya bioterorisme itu berakibat penambahan prosedur dan beban ekonomi yang tidak saja makin berbelit dan biaya tinggi juga waktu dan tahap penyesuaian yang berlarut. Ironinya banyak dugaan dan ataupun isu yang berkembang asal muasal bioterorisme tidak lepas dari kondisi sosekpolkam negara berkembang dan kekhawatiran negara maju yang berlebihan..Di lain pihak akhir-akhir ini digalakkan lagi pembuatan vaksinasi besar-besaran guna mengantisipasi aksi ini. engan pemberian vaksinasi dimungkinkan seseorang mengalami kekebalan permanen terhadap penyakit yang ditimbulkan spesies yang sama, meski sampai saat ini lebih kurang seperempat abad lalu penyakit ini dinyatakan telah musnah, misalnya penyakit cacar (variola). KesimpulanMikroorgansime sebagai bagian struktur biotik dalam ekosistem maupun biosfer memiliki peran besar dalam kehidupan umat manusia di planet bumi ini, yang berfungsi unik, sebagai pengurai atau dekomposer dalam tingkatan trofik ekosistem yang seringkali sangat bermanfaat bagi keberlanjutan kehidupan dan kesejahteraan umat manusia. Namun di pihak lain mikroorganisme dapat berakibat merusak dan kehancuran sendi-sendi kehidupan umat manusia itu sendiri bilamana manusia tidak dapat mengendalikannya ataupun diri manusia itu sendiri.Bentuk penyalahgunaan peran mikroorganisme yang tidak sepatutnya seperti bioterorisme, dan sebaliknya yang seharusnya untuk kemaslahatan umat manusia, dapat berdampak sangat luas memasuki sendi-sendi kehidupan manusia. Oleh Edwi Mahajoeno
On the flow of a class of viscoinelastic–viscoplastic fluids in tubes of non-circular contour
A unified analysis based on natural coordinates is presented for a class of viscoinelastic–viscoplastic fluids for the case of nearly viscometric flows driven by steady pressure gradients in straight ducts of arbitrary cross-sectional contour. General relationships which give phenomenological insight and which yield qualitative information, and some quantitative information as well, concerning the velocity and shear-stress fields of the family of fluids considered in this paper are derived for the case of flow in tubes of non-circular contour, and several applications are discussed.Mario F. Letelier and Dennis A. Siginer
Read more ....
Optimization of tool wear in turning using genetic algorithm
Optimization has significant practical importance particularly for operating in machines. In order to increase the accuracy of finishing product the tool must be in good condition always as much as possible. To achieve good condition of tool the machining parameters like speed, feed and depth of cut should be optimized2-4. This paper aims to increase the condition of tool, i.e., minimization of tool wear by applying the optimized input parameters using Genetic Algorithm technique. For solving the machining problems various traditional techniques such as Integer programming, Quadratic programming and Simplex method have been used so far. But results of these various methods vary to some extent. Genetic Algorithm helps in obtaining better results than of traditional methods available. C Felix Prasad, S Jayabal & U Natarajan
Read more ....
Tuesday, April 8, 2008
Pengaruh besar butir terhadap sifat mekanis baja
In this research, annealing processes were carried out on low carbon steel to produce different grain sizes. The specimens were examined by using metalography and grain size measurement followed by mechanical testing. The relation between annealing temperature and grain size, annealing temperature and hardness, and grain diameter and mechanical properties were made. The equation suggested by Hall-Petch was evaluated for the metal of interest. A qualitative and quantitative analysis of influence of grain size on the mechanical properties is conducted. The results show that increasing of the annealing temperature lead to the growth of grains, which are followed by decreasing of the hardness and other mechanical properties. The Hall-Petch equation ca be applied successfully to the investigated steel. Agus Suhartono BPPT
Read more ....
Biaya riset dan pengembangan perlakuan akuntansi serta pelaporannya untuk manajemen
In the competition era, the research and development activity is one of the ways which many managers choose to survive their company. The specific character of research and development activities are : a research project which may take years to reach the fruition, need lots of funds, the results are difficult to measure quantitatively, and insufficient certainty factor. Acconting treatment for research and development expenses, which declared by Ikatan Akuntan Indonesia (IAI) in 1994 as stated in Statement of Financial Accounting Standards (PSAK) No. 20, invites pro and contra reactions. From the management perspective, research and development activities should be looked as a long-term investment. Heryanto S. Gani
Read more ....
Analisis konfigurasi penyangga pipa dengan menggunakan program caesar II
Analysis of Pipe Support Configuration by Using Caesar II code. A part of design activities for piping system is an adjusted analysis to know pipe stress distribution at support points. As an example of analysis in this paper is the AP600 gas piping system, which is supplied from a distibution pipe and used to rotate turbine that is directly connected to a pump shaft. the temperature of gas that flows through the pipe is 380drajatC with the pressure of 50 bar and fluid density of 14.72 kg/m3. The total of supports used along the analysed pipe are 12 types of restrains, 5 types of guide, 2 toppers, 3 spring hangers and 1 movement anchor. the correct configuration of supports can be known from the verifivation of stress to actial loads at support nozzle equipment nodes. With reference to the analytical steps carried out, the program of CAESAR II can be considered to satisfy the condition used as an analytical cool for the support configuration so that the pipe stress is unigornly distibute. Y. B. Sitandung-BATAN
Read more ....
Tinjauan Terhadap Kebijakan Dan Strategi Nasional Konservasi Ekosistem Terumbu Karang
One of Indonesia riches of sea which can be a non direct capital for development of the nation is corral reefs, Because of this it is proper if Indonesia try to set up the national policy and strategy to conservate the corral reefs. this paper will be taken by the Indonesia Government in order to conservate and to managed the corral reefs. Soetan Budhi S. Sjamsoeddin
Read more ....
Metode Estimasi Peningkatan Yield Strength Material Akibat Pengerjaan Dingin (Cold Working) di Sudut Lengkung Struktur Baja Ringan
A cold forming process on the design of lightweight steel structures can result in the increase of material mechanical properties of the structures at the exact loction where the cold working process takes place. two methods of estimating the increase on the yield strength of the structural materials at the bend cornerhave been used here. Both methods are based on bend comer models affected by bending only (A purely flexural-loaded comer model) and by interaction of bending and radial pressure ( A combined-flexural and radial pressure corner model). Investigation on the increase of yield strength is aimed at the bend corner material of a lightweight channel steel section cold-formed using a plate folding machine. The increase of yield strength estimated by both models is compared to the yield strength of the ssction virgin material. Observation on the comarison results of yield strength before and after cold forming indicates that the percentage of increasing yield strength is extremely affected by variation on parameters of bend corner radius and mechanical properties of the section virgin material. Harkali etiyono-BPPT
Read more ....
Retakan pelat aluminium dengan perbaikan graphite epoxy
The goal of this paper is to know crack propagation charcteristic on aluminium plate with repair graphite epoxy. The mechanical properties static and dynamic constitutes as urgent factor, then is necessity to establish a research crack propagation on the aluminium plate. From the research propagation on aluminium plate up to 58 mm and composite material failure ono 165.150 cycle.
Keywords: crack, propagtion, fatigue life. Sasi Kirono-BPPT
Read more ....
Keywords: crack, propagtion, fatigue life. Sasi Kirono-BPPT
The Role of Information Technology and Informatics Research in the Dentist-Patient Relationship
A high-value doctor-patient relationship is based on a set of parameters which include the interpersonal relationship between the patient and the doctor. Based on the Primary Care Assessment Survey model, measures of the interpersonal relationship are associated with communication, interpersonal care, contextual knowledge of the patient, and trust. Despite the proven value of the doctor-patient relationship, current trends indicate that the quality of these relationships is on the decline. The advent of communication and information technologies has greatly affected the way in which health care is delivered and the relationship between doctors and patients. The convergence of communication and information technology with biomedical informatics offers an opportunity to affect the character of the doctor-patient relationship positively. This paper examines the intersection of the key features of the doctor-patient relationship and a variety of Internet-based, clinical, and administrative applications used in dental practice. This paper discusses the role of dental informatics research vis-Ã -vis the doctor-patient relationship and explores how it may inform the next generation of information technologies used in dental practice. KEY WORDS: Dentistry • information systems • medical informatics • patient-centered care • physician-patient relations. M. Kirshner; michael.kirshner@kp.org
Read more ....
Tantangan dan peluang bagi perguruan tinggi swasta di Jakarta
This article indicates that the challenges for private univertities to update themselves depends on the opportunities they get in upgrading the academic staff members. In the era of globalisation, private universities must cooperate with their foreign counterparts, to enhance the demand of link and match standards in science and technology, as well as in business and management. How far are the challenges and opportunities used by these private universities it is still a question in the future.
Read more ....
Karakteristik Resin Penukar Ion
Resin penukar ion dapat didefinisi sebagai senyawa hidrokarbon terpolimerisasi, yang mengandung ikatan hubung silang (crosslinking) serta gugusan-gugusan fungsional yang mempunyai ion-ion yang dapat dipertukarkan. Sebagai zat penukar ion, resin mempunyai karakteristik yang berguna dalam analisis kimia, antara lain kemampuan menggelembung (swelling), kapasitas penukaran dan selektivitas penukaran. Penggunaannya dalam analisis kimia misalnya untuk menghilangkan ion-ion pengganggu, memperbesar konsentrasi jumlah ion-ion renik, proses deionisasi air atau demineralisasi air, memisahkan ion-ion logam dalam campuran dengan kromatografi penukar ion.(Mahmudi, Universitas Negeri Malang)
Read more ....
Agama Dalam Dialog Dengan Sains
The relationship between the religion and science is often marked with the conflict which is difficult to be peacefully resolved yet religion and science, basically has its own similar interst that is for the good of human being. Religion as well as science has just is significant when it is dedicated to the good of human beings. For that reason, religion and science need to build a constructive dialogue because science without religion is blind and religion without science is lame. Rafael Raga Maran.
Read more ....
Suhu NIL Ductility Transition Pada Pelat Baja Untuk Body Kapal
Nil Ductility Transition Temperature of steel is most important to be known before application especially at low temperature. Steels that are ductile in room temperature become to be brittle at low temperature. Transition temperature of high strength steel for wall ship application has been studied with using drop weight test method. This Method had been used extensively to investigate conditions required for initiation of brittle fracture in structural steel. Range temperature of examination was -40drajatC to -65drajatC with using alcohol media that was colded by dry ice. Result examinatian shown that the nil-ductility transition temperature of the high strength steel is -63drajatC. Keywords: nil-ductility transition temperature, ductile, brittle, high strength steel. Kurman M.-BPPT
Read more ....
Bagaimana Coating Melawan Korosi Bagian 1 (Metallic Coating Dan Inorganic Coating)
Coating is the materials that are use to coat (cover) the surface of substrate such as metal, wood andconcrate to protect from the effect of the environment, and it can also be used as decorative purposes. Coating applied on the surface is mainly aimed at protecting against corrosion and it can be in the from of metallic or non metallic coating materials. The system of the organic coating such as paint are widely used and easy to apply, relatively is inexpensive and recoatable. This paper will describe the fuction and the ability of the coating especially paint to protect the corrosion attact. Iing Musalam-LIPI
Read more ....
Pengukuran dan prediksi tebal crud kelongsong AL bahan bakar maju reaktor Hanaro
Measurement and prediction of crud thickness on Al clad of advanced fuel for HANARO reactor. Measurement of crud thickness on fuel of research reactor fuel test irradiated in 2000 has been performed. During irradiation of Al 1100 clad, the cooling water was maintained at temperature <100drajatc,> 5 MOhm.m, inside channel flow 8 m/s. The cladding surface temperature has been predicted between 100-120drajatC. The irradiation has been conducted for 60 days, average and maximum bumup 10 and 12.9% respectively. Prediction of crud thickness was carried out by using correlation estabilished by JAERI in 1965 based on ex-core experiment. The purpose of the study is evaluating the correlation between prediction and measurement of crud thickness. The thickness measurement has been conducted by using ImageProAnalysis software for metallurgical image of irradiated fuel pin cross-sections. The average thickness of each cross-sections are 23.95, 12.96 and 10.91 um from the highest to lowest surface temperature, with <12%>
Read more ....
Crystal Structure Of 11-(Indol-3-yl)benzo(b)carbazole
New 11-(3-indoly)benzo(b)carbazoles (9) has been synthesised in good yield from the reation of indole and o-phthaldialdehid in dry chloroform catalysed by phosphoryl chloride. An X-ray crystal structure determination has been carried to estabilish the structure of benzocarbazole (9). keywords: indole, o-phthaldialdehid, new benzo(b)carbazole. Mardi Santoso
Read more ....
Perkembangan Konsep Atom (Ida Bagus Suryadharma, Universitas Negeri Malang)
Untuk memahami konsep atom dengan benar perlu dipahami proses penemuan partikel-partikel penyusun atom dan perkembangan konsep atom itu sendiri. Teori atom untuk menjelaskan reaksi kimia, pertama kali diajukan oleh Dalton. Atom merupakan partikel terkecil penyusun semua zat yang tak dapat dibagi lagi. Kemudian dengan ditemukannya elektron dan proton yang merupakan partikel penyusun atom, maka dikemukakan berbagai model atom seperti model atom Thomson, yang menganggap atom sebagai bola masif dengan seluruh muatan positif tersebar merata dan elektron berada didekatnya. Model atom Rutherford menganggap atom mempunyai inti yang terdiri dari proton dan netron sedangkan elektron mengelilingi inti jauh di luar inti. Dengan adanya penemuan spektrum atom hidrogen kemudian Bohr mengajukan teori atomnya yang berlandaskan teori Planck. Kemudian dengan sifat gelombang elektron yang dijelaskan oleh de Broglie dan prinsip ketaktentuan Heisenberg dikembangkan model atom mekanika gelombang yang didasarkan pada persamaan Schrodinger.
Read more ....
Degradasi Nitrat Melalui Reduksi Elektrokimia
Destruction of nitrate compounts could be carried out in electrochemical redox processing using porous electrodes. Cell performances were calculated from efficiencies of destruction and supplied electrical current. Influent containing 50 ppm of nitrate was flowed through porous carbon fielt and titanium-coated platinum electrodes. The supplied electrical current affected the destruction efficiency. When 2A electrical current was applied, the process efficiency was approximately 85% (for the destruction) and 29.02% (electrical current) but these effisiencies were lower when the supplied current differed. Increasing of pH and solution temperature were observed during the experiments. The coefficients of mass transfer were estimated from the process mass balances and the electrical current. keywords: destruction of nitrate, electrochemical redox processing, porous electrodem electrical current. Lilis Hermida and E.P.L.R. roberts
Read more ....
The impact of CHIP generation on CO2 emissions
The combined generation of heat and power (cogeneration) is praised by many as a technique for reducing the emissions of O2 in industrial ized nations. This is generally true but not always. In this article we discuss the impact of some major variables on the CO2 emission reduction capacity of cogeneration. Two sets of variables are predominant: the characteristic of the CHP process and the composition of the electricity generation sector. We highlight the interaction between the two sets of variables with the help of diagrams. Keyword: Cogeneration; CO2 emissions; Energy technologeies Aviel Verbruggen, michael Wiggin, Nadine Dufait and Adwin Martens.
Read more ....
Economic restructuring in Eastern Europe and acid rain abatement strategies
Acid rain abatement strategies in Europe are currently being discussed in view of the expiration of the Helsinki Protocol on SO2 emission reduction. The changing energy situation in Eastern European countries is expeced to have an influence on the deposition pattern in Europe. The paper presents a consistent and compares optimal strategies to reduce SO2 emissions. These strategies are based on runs with the RAINS model in which environmental targets have been set based on critical loads for sulphur. The analysis shows that economic restructuring and efficiency improvements in Eastern European countries, as well as in Western Europe, may result in significantly lower sulphur abateent costs. Potential assistance to Eastern Europe to guarantee desired environmental standards in Western countries should therefore focus not only on providing emission control devices but also on the success of the economic transition process. Keywords: Acid rain; Eastern Europe; Abatement strategy Markus Amann, Leen Hordijk, Ger Klaassen, Wolfgang Schopp and Lene Sorensen.
Read more ....
Monday, April 7, 2008
Export Processing in Saint Lucia: Ownership, Linkages and Transfer of Technology
The author reports the results of May 1993 field work in St Lucia's export processing plants, which supplied more than half the jobs in manuafacturing and 6% of all jobs in the economy that year. Keywords: Saint Lucia, export promotion LARRY WILLMORE; International Institute for Applied Systems Analysis (IIASA)
Read more ....
Information Technology and the Knowledge Elites
This Paper studies a model where Information Technology, while typically increasing overall inequality, is likely to harm some people at intermediate and high levels of the distribution of income but to benefit people at the bottom; where within a given occupation it may harm some workers while benefiting others; and where it may either reduce or increase the proportion of knowledge workers in employment, depending on the response of the overall demand for knowledge to the implied reduction in the cost of acquiring it. In my model, knowledge (in a broad sense) is an input into the production function of human capital, and is also a 'quality' good in the sense that one cannot buy it from several low-quality producers instead of one high-quality one. People differ in their exogenous ability and ability is complementary with the quality of the knowledge input in the production of human capital. An improvement in IT is modelled as an increase in the number of people who can buy knowledge from one producer. I show that the economy organizes itself in a succession of clusters of ability levels, called "knowledge ladders", where a member of a given ladder buys knowledge from a worker in the subsequent ladder and sells it to a worker of the preceding ladder. The return to human capital increases as one moves up the knowledge ladder. The economic mechanism considered here rests on the view that IT makes the acquisition of knowledge cheaper, which intensifies competition among workers specialized in knowledge production. Those who lose in such competition end up displaced to occupations with a lower knowledge intensity; their wages fall, which reduces inequality between them and the least skilled. Those who win can spread their ability over a larger market and because of that enjoy a larger increase in wages than the least skilled, which tends to increase inequality. The least skilled do not participate in this competition, as they are not specialized in knowledge production; they gain in absolute terms because of their cheaper access to knowledge. Keywords: Computers, human capital, income distribution, information technology, knowledge, overlapping generations, worker assignment, worker displacement. GILLES SAINT-PAUL; University of Toulouse I - GREMAQ-IDEI; Centre for Economic Policy Research (CEPR); CESifo (Center for Economic Studies and Ifo Institute for Economic Research); Institute for the Study of Labor (IZA).
Read more ....
Energy consumption and modes industrialization
Four developing countries. Because of heterogeneity of developing countries, energy consumption dynamics can only be analysed at the level of individual countries. This paper focuses on the comparison of the energy consumption dynamics of South Korea, India, Brazil and Mexico and on the origins of the dynamics observed. It is shown that the same factors explain the diversified energy consumption dynamics: the national availability of energy resources, the energy policies and the modes of industrialization adopted, as well as the patterns of private consumption.Keywords: Energy consumption dynamics; Developing countries; Mode of industrialization. Odile Blanchard
Read more ....
KOMPOR ELEKTROSOLAR SEBAGAI BENTUK PENGGABUNGAN DUA TEKNIK PEMANFAATAN SINAR MATAHARI
(Prinsip Kerja Solar Cell dan Efek Rumah Kaca). Penelitian ini dilaksanakan pada hari Selasa-Kamis tanggal 4-6 Juli 2006 di Pusat Pendidikan Lingkungan Hidup di desa Seloliman, Kecamatan Trawas, Kabupaten Mojokerto, Jawa Timur. Penelitian ini menggunakan beberapa teknik pengumpulan data, yaitu studi pustaka untuk mendapatkan informasi tentang bahan-bahan yang digunakan sekaligus sebagai penguat landasan berpikir, wawancara orang yang berkompeten dan dokumentasi penelitian. Solar cell adalah suatu alat yang menggunakan energi matahari sebagai bahan dasarnya dan merubahnya menjadi bentuk energi yang dapat disimpan yaitu energi llistrik. Efek rumah kaca yaitu suatu fenomena yang terjadi karena tidak bisa keluarnya energi dari gelombang sinar infra merah di suatu strukture karena adanya filter yang membuat gelombang infrared tidak bisa merambat keluar dan terpantul kembali. Kompor elektro solar adalah suatu alat yang didsain agar memungkinkan pemaduan kedua system tersebut. Hal itu dikaitkan dengan effesiensi struktur bahan elevasi dan juga bentuk dan penempatannya. Penelitian ini bertujuan untuk mengetahui cara kerja kompor elektrosolar, untuk mengetahui prinsip kerja kompor elektrosolar dan untuk mengetahui kebersihan dan keefektifan dari kompor elektrosolar. Kesimpulan dari penelitan ini ialah: Pertama, pada siang hari, penggunaan kompor elektrosolar ini memanfaatkan prinsip efek rumah kaca. Prinsip ini memungkinkan pemanasan yang terjadi di dalam kompor dapat merata. Kompor ini menggunakan cermin datar sebagai dinding yang berfungsi untuk merefleksikan sinar matahari yang masuk ke dalam kompor. Sedangkan pada malam hari, pemanasan dilakukan dengan menggunakan prinsip solar cell. Pertama-tama peneliti mengambil energi matahari dengan menerapkan prinsip solar cell yang kemudian langsung disimpan di dalam aki. Jika dibutuhkan untuk memasak, maka energi matahari yang telah diubah menjadi energi listrik bisa langsung diambil dari aki tersebut. Hal itu terjadi karena energi listrik dari aki akan diubah menjadi energi panas dengan bantuan elemen pemanas; Kedua, prinsip kerja kompor elektrosolar ini ialah penggabungan dua teknik pemanfaatan sinar matahari, yaitu teknik solar cell dan efek rumah kaca. Sehingga dua teknik tersebut dapat saling memenuhi kekurangan dari keduanya; Ketiga, pemanfaatan energi matahari secara optimal dapat menghemat energi dan pengeluaran biaya sehari–hari masyarakat. ADYA UTAMI
Read more ....
Electricity privatization
Structural, competitive and regulatory options. Privatization is probably the most important economic and political phenomenon of this decade. This article analyses the structural, competitive, and regulatory options that are available to an existing or newly privatized electricity sector. Drawing on economic, engineering and legal insights, it presents four basic models of industry structure and examines how these structures interact with different competitive and regulatory approaches. The interactions are analysed with examples from recent US, UK and European experience. The article identifies the critical linkage between proper selection among these options and the long-term success or failure of the privatization
initiative and it presents some conculusions on the causes of success and failure.Keywords: Electricity privatization; Competition; RegulationBerbard Tenenbaum, Reinier Lock and Jim Barker.
Read more ....
initiative and it presents some conculusions on the causes of success and failure.Keywords: Electricity privatization; Competition; RegulationBerbard Tenenbaum, Reinier Lock and Jim Barker.
Peran Strategik Pelatihan dalam Pengembangan Sumberdaya Manusia untuk Meningkatkan Daya Saing Lembaga
Training is a strategic tool to strengthen the competitiveness of organizations through human resource development. To support achieving the strategic objective of organization, it is important to establish a link between strategic planning of organization and its training program. There are five core principles of learning in training design to guarantee better results. A case study will be presented to indicate that applying those principle into practice will increase the competitive edge of a team.Hisyam Said-BATAN
Read more ....
Pengamanan Sumber Radiasi
A complete programme aimed at addressing the malevolent use of radioactive sources needs to consider a large range of issues including: the appropriate design and manufacture of sources, the various means of acquisition of sources, the prevention of use any sources acquired, and the mitigation of the impacts if sources are used maliciously. In this paper will be described the process to determine what level of security is required for sources throughout their lifecycle, and the assignment level of security is required for sources throughout their lifecycle, and the assignment of security measures to sources based on graded performance requirements to deter, detect, and if necessary respond to theft of radioactive material. by Rini Rindayani
Read more ....
An Application of Radio Acoustic Sounding System (RASS)......
An Application of Radio Acoustic Sounding System (RASS) with Equatorial Atmosphere Radar (EAR) for Contimuous Measurement of Atmospheric Virtual Temperature over Kototabang, West Sumatera. We have introduced a new Equatorial Atmosphere Radar (EAR) in a collaboration project between radio science center for space and atmosphere (RASC). Kyoto University, Japan and the Indonesia National Institute of Aeronautics and Space (LAPAN) at Kototabang. Bukittinggi, West Sumatera. This radar is mainly designed to observe winds and turbulence in the troposphere and lower stratosphere with a good time and spatial height resolution. Numerous studies or research program with the EAR have been planned. One of them is the observation of fine structure in the vertical profile of atmospheric temperature using Radio Acoustic Sounding System (RASS). Since the full instruments are under construction, we present in this paper a brief review of the basic principle of RASS. especially on the design of acoustic transmitter measurements with EAR. Aan example the comparison between RASS and radiosonde data on 6 November 2001 is also presented. Keywords: equatorial atmosphere radar (ear), rass, virtual temperatureEddy Hermawan.
Read more ....
Friday, April 4, 2008
KOMPOR ELEKTROSOLAR SEBAGAI BENTUK PENGGABUNGAN DUA TEKNIK PEMANFAATAN SINAR MATAHARI
(Prinsip Kerja Solar Cell dan Efek Rumah Kaca) Penelitian ini dilaksanakan pada hari Selasa-Kamis tanggal 4-6 Juli 2006 di Pusat Pendidikan Lingkungan Hidup di desa Seloliman, Kecamatan Trawas, Kabupaten Mojokerto, Jawa Timur. Penelitian ini menggunakan beberapa teknik pengumpulan data, yaitu studi pustaka untuk mendapatkan informasi tentang bahan-bahan yang digunakan sekaligus sebagai penguat landasan berpikir, wawancara orang yang berkompeten dan dokumentasi penelitian. Solar cell adalah suatu alat yang menggunakan energi matahari sebagai bahan dasarnya dan merubahnya menjadi bentuk energi yang dapat disimpan yaitu energi llistrik. Efek rumah kaca yaitu suatu fenomena yang terjadi karena tidak bisa keluarnya energi dari gelombang sinar infra merah di suatu strukture karena adanya filter yang membuat gelombang infrared tidak bisa merambat keluar dan terpantul kembali. Kompor elektro solar adalah suatu alat yang didsain agar memungkinkan pemaduan kedua system tersebut. Hal itu dikaitkan dengan effesiensi struktur bahan elevasi dan juga bentuk dan penempatannya. Penelitian ini bertujuan untuk mengetahui cara kerja kompor elektrosolar, untuk mengetahui prinsip kerja kompor elektrosolar dan untuk mengetahui kebersihan dan keefektifan dari kompor elektrosolar. Kesimpulan dari penelitan ini ialah: Pertama, pada siang hari, penggunaan kompor elektrosolar ini memanfaatkan prinsip efek rumah kaca. Prinsip ini memungkinkan pemanasan yang terjadi di dalam kompor dapat merata. Kompor ini menggunakan cermin datar sebagai dinding yang berfungsi untuk merefleksikan sinar matahari yang masuk ke dalam kompor. Sedangkan pada malam hari, pemanasan dilakukan dengan menggunakan prinsip solar cell. Pertama-tama peneliti mengambil energi matahari dengan menerapkan prinsip solar cell yang kemudian langsung disimpan di dalam aki. Jika dibutuhkan untuk memasak, maka energi matahari yang telah diubah menjadi energi listrik bisa langsung diambil dari aki tersebut. Hal itu terjadi karena energi listrik dari aki akan diubah menjadi energi panas dengan bantuan elemen pemanas; Kedua, prinsip kerja kompor elektrosolar ini ialah penggabungan dua teknik pemanfaatan sinar matahari, yaitu teknik solar cell dan efek rumah kaca. Sehingga dua teknik tersebut dapat saling memenuhi kekurangan dari keduanya; Ketiga, pemanfaatan energi matahari secara optimal dapat menghemat energi dan pengeluaran biaya sehari–hari masyarakat. ADYA UTAMI
Read more ....
Limbah Bahan Bakar Nuklir
Limbah bahan bakar nuklir adalah suatu materi yang terkontaminasi oleh bahan bakar nuklir atau bahan nuklir yang akan dibuang. Limbah radioaktif ditetapkan berdasarkan "undang-undang tentang ketentuan reaktor, bahan bakar nuklir dan bahan nuklir" (peraturan perundang-undangan reaktor dan lain-lain). Pada kenyataannya, limbah dari industri yang terkena ketentuan peraturan perundang-undangan reaktor dan lain-lain dapat digolongkan sebagai limbah bahan bakar nuklir. BATAN
Read more ....
Penanggung Jawab Penanganan Bahan Bakar Nuklir
Penanggung jawab penanganan bahan bakar nuklir adalah orang yang ditunjuk oleh industri nuklir dan bertangung jawab terhadap penanganan bahan bahan nuklir berdasarkan pasal 22 ayat 2 - ayat 4 peraturan perundang-undangan tenaga nuklir Jepang. Penanggung jawab penanganan bahan bakar nuklir harus mempunyai sertifikat sebagai penanggung jawab penanganan bahan bakar nuklir setelah lulus ujian yang diadakan oleh MEXT, atau memiliki pengalaman dan pengetahuan tentang penanganan bahan bakar nuklir yang minimal setara dengan orang yang telah lulus ujian penanggung jawab penanganan bahan bakar nuklir. Penanggung jawab penanganan bahan bakar nuklir memimpin penanganan keselamatan terhadap bahan bakar nuklir. Orang yang terkait dengan penanganan bahan bakar nuklir harus patuh terhadap perintah penanggung jawab penanganan bahan bakar nuklir demi keselamatan dalam penanganan bahan bakar nuklir. BATAN
Read more ....
Perusahaan Bahan Bakar Nuklir Inggris (British Nuclear Fuels plc)
Sehubungan dengan swastanisasi BNFL, kebijakan swastanisasi BUMN Inggris harus menangani berbagai bidang yang berkaitan dengan daur ulang bahan bakar nuklir. Sebagai akibatnya kegiatan-kegiatan seperti produksi bahan bakar, suplai uranium, olah-ulang (reprocessing), pengiriman bahan radioaktif, manajemen limbah, dan dekomisioning instalasi nuklir juga harus dilakukan. Selain itu, BNFL juga merupakan pemilik serta operator 8 pembangkit listrik tenaga nuklir tipe Magnox yang sedang beroperasi. Instalasi yang ditunjukkan pada gambar merupakan instalasi terbesar di antara 5 instalasi BNFL, yang berlokasi di Sellafield-West Cambria, yang memiliki fasilitas olah-ulang THORP yang dapat melayani semua bahan bakar bekar PLTN seluruh dunia, PLTN komersial pertama di dunia Calder Hall (beroperasi pertama kali pada tahun 1965, sampai saat ini), pabrik produksi bahan bakar MOX dengan skala 120 ton per tahun, serta fasilitas untuk penyimpanan limbah lestari. BATAN
Read more ....
PENGGUNAAN ICT DALAM PENGAJARAN SAINS DAN MATEMATIK
Penggunaan ICT dalam pengajaran Bahasa Inggeris, Matematik dan Sains telah dilaksanakan mulai Januari 2003. Pelbagai pertanyaan telah muncul kerana masa untuk melaksanakan dasar ini agak singkat.