• Journal of Radiation Protection and Research
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• 제29권1호
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• pp.17-23
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• 2004

HPGe 검출기를 이용한 방사능 분석 시 효율교정을 위하여 통상적으로 사용하는 상용의 감마선 표준선원을 구입하는데 따르는 금전적인 문제와 장기간의 소요시간 등의 문제를 해결하기 위하여 본 연구에서는 표준선원을 직접 제작하였다. 측정하고자 하는 에너지 영역의 감마선을 방출하는 핵종이 포함된 시약을 원자로에서 조사시켜 방사화된 시약을 수용액 상태로 만들어 표준선원을 제조하였다. 제조한 방사선원을 상용의 표준선원과 비교하였으며 효율교정용 선원으로 사용할 수 있다는 것을 확인하였다. 또한 일상적인 방사능 분석과정에서 발생할 수 있는 표준선원과 측정 시료의 부피 차이에 따른 측정 효율의 변화정도를 조사하기 위하여 방사능 분석에서 사용되고 있는 다양한 측정용기에 대하여 표준선원의 부피 변화에 따른 효율의 변화 정도를 조사하였다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2019년도 춘계학술대회
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• pp.464-466
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• 2019

원자력 발전소에 사용되는 제어기는 높은 신뢰도를 요구한다. 한국형 디지털 원자력 발전소인 APR1400 (Advanced Power Reactor 1400)을 비롯하여, 과거 많은 원자력 발전소에 FPGA (Field Programmable Gate Array)와 CPLD (Complex Programmable Logic Device, 이하 FPGA로 통칭)가 포함된 제어기가 적용되고 있다. 적용 초기에는 FPGA를 일반적인 IC (Integrated Circuit)처럼 기기검증 및 성능시험으로만 검증을 하였다. 이후 90년대에 들어 FPGA검증에 대한 연구가 시작되면서, FPGA가 칩이 되기 전까지를 소프트웨어로 간주하여 IEEE 1012-2004를 적용하여 소프트웨어 확인 및 검증을 하였다. 현재에는 유럽표준인 IEC 62566을 적용하여 많은 검증을 하고 있다. 이 방법은 현재까지 가장 현명한 방법으로 평가 받고 있다. 이유는 기존의 검증 방법에서 문제가 되었던 SoC (System on Chip)의 특징을 검증하는 방법을 충분히 적용하였기 때문이다. 하지만, IEC 62566은 유럽 표준으로 아직 미국에서는 채택을 하지 않고 있으며, FPGA에 대해서는 IEEE 1012를 적용하는 것을 유지하고 있다. IEEE 1012-2004나 IEC 62566은 기술 표준으로 실무에서는 다양한 방법을 적용하여 기술 표준을 충족시켜서 적용하고 있다. 이 논문에서는 SoC의 검증 방법이 적용된 원자력 안전등급 FPGA에 대한 검증 방법의 절차 및 중요사항에 대해 설명하고자 한다.

• 한국응용과학기술학회지
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• 제22권4호
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• pp.332-338
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• 2005

This study was conducted to prepare acrylic removable protective coatings by emulsion polymerization. Monomers used were n-butyl acrylate, acrylonitrile, butyl methacrylate. Emulsifiers used were sodium lauryl sulfate and polyoxyethylene lauryl ether, which are an anionic emulsifier and a nonionic emulsifier respectively. Potassium persulfate was used as an initiator and polyvinyl alcohol was used as a stabilizer. Emulsion polymerization was carried out in a semi-batch reactor at $70^{\circ}C$ and agitation speed was 200 rpm. Tensile strength, extension, peel strength, viscosity, and solid contents of the synthesized coatings were examined. The coatings prepared with BA:AN = 60:20 (in weight ratio) satisfied the standard for automobile in terms of extension and peel strength. When the concentration of BMA was in a range of $18{\sim}23$ wt%, the prepared coatings satisfied the standard for automobile in terms of peel strength and water resistance.

• 대한수의학회지
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• 제22권2호
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• pp.149-153
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• 1982

Results obtained from six secological tests for diagnosing bovine brucellosis-standard plate agglutination test (SPT), standard tube agglutination test(STT), complement fixation test(CFT), Rivanol test (RT), agar gel precipitation test (AGP) and counterimmunoelectrophoresis(CIEP) were compared using 38 sera from brucella reactors and 222 sera from dairy and beef cattle in field. The SPT gave 1.6% apparent false negative reactions and 15.4% apparent false positive reactions when compared with STT which is an official test for bovine brucellosis in this country. The distribution of antibody titers determined by STT showed that 37.5% of 38 reactors had antibody titers ranging from 100 to 200, and the remaining 62.5% had antibody titers of 400 or higher. when 38 reactor judged by STT were tested by CFT and RT, 32 cattle(82.4%) were positive by CFT and 33 cattle (86.8%) were positive by RT, respectively. This results suggest that RT is comparable to CFT in the diagnosis of bovine brucellosis. The results also indicated that both AGP and CIEP were insensitive to detect brucella infection in cattle.

• 한국CDE학회논문집
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• 제12권3호
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• pp.191-199
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• 2007

In order to construct a data warehouse of process plant equipment, a classification structure should be defined first, identifying not only the equipment categories but also attributes of an each equipment to represent the specifications of equipment. ISO 15926 Process Plants is an international standard dealing with the life-cycle data of process plant facilities. From the viewpoints of defining classification structure, Part 2 data model and Reference Data Library (RDL) of ISO 15926 are seen to respectively provide standard syntactic structure and semantic vocabulary, facilitating the exchange and sharing of plant equipment's life-cycle data. Therefore, the equipment data warehouse with an ISO 15926-based classification structure has the advantage of easy integration among different engineering systems. This paper introduces ISO 15926 and then discusses how to define a classification structure with ISO 15926 Part 2 data model and RDL. Finally, we describe the development result of an ISO 15926-based classification structure for a variety of equipment consisting in the reactor coolant system (RCS) of APR 1400 nuclear plant.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2002년도 추계기술심포지움논문집
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• pp.115-121
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• 2002

In this research we have investigated the characteristics of ultra thin $HfO_2 /SiON$stack structure films using several analytical techniques. SiON layer was thermally grown on standard SCI cleaned silicon wafer at $825^{\circ}C$ for 12sec under $N_2$O ambient. $HfO_2 /SiON$$_4$/$H_2O$ as precursors and $N_2$as a carrier/purge gas. Solid HfCl$_4$was volatilized in a canister kept at $200^{\circ}C$ and carried into the reaction chamber with pure $N_2$carrier gas. $H_2O$ canister was kept at $12^{\circ}C$ and carrier gas was not used. The films were grown on 8-inch (100) p-type Silicon wafer at the $300^{\circ}C$ temperature after standard SCI cleaning, Spectroscopic ellipsometer and TEM were used to investigate the initial growth mechanism, microstructure and thickness. The electrical properties of the film were measured and compared with the physical/chemical properties. The effects of heat treatment was discussed.

• 기술사
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• 제44권6호
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• pp.40-44
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• 2011

Nuclear energy in Korea began in 1958, when the Korea's atomic energy act was formulated and the relevant organizations were founded. Since then, notwithstanding the two catastrophe like TMI and Chernobyl accident, Korea made a wise decision to expand the peaceful uses of the nuclear energy as well as to localize the essential nuclear design technology of fuel and nuclear steam supply system. This decision resulted in the success of export of nuclear power plants as well as research reactor in 2010s. The Korea's nuclear policy, which well utilized 'international crisis in nuclear business' as 'opportunity of Korea to get. nuclear technology', is believed nice policy as a role model of nuclear new-comer countries. Based upon the success story of localization of nuclear technology, Korea had an eye for a niche market, which was a basis of development of SMART, Korea-made integral PWR. The operation of a SMART plant can sufficiently provide not only electricity but also fresh water for 100,000 residents. Last two years, Korea's nuclear industry team led by the Korea Atomic Energy Research Institute completed the standard design of SMART and applied to the Korea's regulatory body for standard design approval. Now the Korea's licensing authority is reviewing the design with the relevant documents, and the design team is doing its best to realize its hope to get the approval by the end of this year. From next year, the SMART business including construction and export will be explored by the KEPCO consortium.

• Nuclear Engineering and Technology
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• 제27권2호
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• pp.234-247
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• 1995

Trace elements in airborne particulates were analyzed by instrumental neutron activation analysis (INAA) under the optimum analytical condition. Neutron irradiation for sample was done at the irradiation hole(neutron flux 1$\times$10$^{13}$ n/$\textrm{cm}^2$.s) of TRIGA MARK-III research reactor in the Korea Atomic Energy Research Institute. For the verification of the analytical method, NIST SRM-1648 and NIES CRM No.8 ore chosen and analyzed. The accuracy and precision of the analysis of 40 and 24 trace elements in the samples were compared with the certified and reported values, respectively. The analytical method was found to be reliable enough when the analytical data of NIES sample were compared with those of different counties. In the analytical result of two or both of standard reference materials, relative standard deviation wes within the 15％ except a few elements and the relative error was within the 10％. We used this method to analyze 30 trace elements in airborne particulates collected with the high volume air sampler(PM-10) at too different locations and also confirmed the possibility to use this method as a routine monitoring tool to find out environmental pollution sources.

• Nuclear Engineering and Technology
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• 제41권6호
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• pp.797-806
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• 2009

The Multichannel Analyzer for Transient and steady-state in Rod Array - Liquid Metal Reactor for Flow Blockage analysis (MATRA-LMR-FB) code for the analysis of a subchannel blockage has been developed and evaluated through several experiments. The current version of the code is improved here by the implementation of a distributed resistance model which accurately considers the effect of flow resistance on wire spacers, by the addition of a turbulent mixing model, and by the application of a hybrid scheme for low flow regions. Validation calculations for the MATRA-LMR-FB code were performed for Oak Ridge National Laboratory (ORNL) 19-pin tests with wire spacers and Karlsruhe 169-pin tests with grid spacers. The analysis of the ORNL 19-pin tests conducted using the code reveals that the code has sufficient predictive accuracy, within a range of 5 $^{\circ}C$, for the experimental data with a blockage. As for the results of the analyses, the standard deviation for the Karlsruhe 169-pin tests, 0.316, was larger than the standard deviation for the ORNL 19-pin tests, 0.047.

• 상하수도학회지
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• 제19권4호
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• pp.497-505
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• 2005

Domestic Sewage Treatment Plants are mostly based on biological treatment, in which large amounts of excess sludge are generated and occupy about 40 ~ 60% of the total sewage treatment costs. Several methods for sludge treatment has been so far reported as upgrading biodegradation of sludge; heat treatment, chemical treatment, including thermo-alkali and ozone, mechanical treatment including ultrasonic pulverization. But, it has a limitation in case of reducing the amount of excess sludge which are already producted. In this study, application of excess sludge reduction process using thermophilic aerobic bacteria for activated sludge was examined. The research was carried out two different stage. one for a biological wastewater treatment and the other for a thermophilic aerobic solubilization of the waste sludge. A portion of excess sludge from the wastewater treatment step was into the thermophilic aerobic sludge solubilization reactor, in which the injected sludge was solubilized by thermophilic aerobic bacteria. The solubilized sludge was returned to the aeration tank in the wastewater treatment step for its further degradation. Sludge solubilization reactor was operated at $63{\pm}2^{\circ}C$ with hydraulic retention time(HRT) of 1.5 ~ 1.7 day. Control group was operated with activated sludge process(AS) and experiment group was operated with three conditions(RUN 1, RUN 2, RUN3). RUN 1 was operated with AS without sludge solubilization reactor. RUN 2 were operated with AS with sludge solubilization reactor to examine correlation between sludge circulation ratio and sludge reduction ratio by setting up sludge circulation ratio to 3. RUN 3 was operated with sludge circulation ratio of 3 and MLSS concentration of 1,700~2,000mg/L to examine optimum operation condition. The quantity of excess sludge production was reduced sharply and in operation of RUN 3, sludge The quantity of excess sludge production was reduced sharply and in operation of RUN 3, sludge solubilization ratio and sludge reduction ratio were 53. 7%, 95.2% respectively. After steady state operation, average concentration of TBOD, SBOD, $TCOD_{Cr}$, $SCOD_{Cr}$, TSS, VSS, T-N, T-P of effluent were 4.5, 1.7, 27 .8, 13.8, 8.1, 6.2, 15.1, 1.8mg/L in the control group and were 5.6, 2.0, 28.6, 19.1, 9.7, 7.2, 16.1, 2.0mg/L in the experimental group respectively. They were appropriate to effluent standard of Sewage Treatment Plants.