• Nuclear Engineering and Technology
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• 제38권7호
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• pp.591-618
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• 2006

An integrated R&D program is being conducted to study, qualify, and in some cases, develop materials with required properties for the reactor systems being developed as part the U.S. Department of Energy's Generation IV Reactor Program. The goal of the program is to ensure that the materials research and development (R&D) needed to support Gen IV applications will comprise a comprehensive and integrated effort to identify and provide the materials data and its interpretation needed for the design and construction of the selected advanced reactor concepts. The major materials issues for the five primary systems that have been considered within the U.S. Gen IV Reactor Program-very high temperature gas-cooled, supercritical water-cooled, gas-cooled fast spectrum, lead-cooled fast spectrum, and sodium-cooled fast spectrum reactors-are described along with the R&D that has been identified to address them.

• 한국기계기술학회지
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• 제13권2호
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• pp.145-153
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• 2011

The irradiation tests of materials in HANARO have been performed usually at temperatures below $300^{\circ}C$ at which the RPV(Reactor Pressure Vessel) materials of the commercial reactors such as the light water reactor and CANDU are operated. As VHTR(Very High Temperature Reactor) and SFR(Sodium-cooled Fast Reactor) projects are being carried as a part of the present Gen-IV program in Korea, the requirements for irradiation of materials at temperatures higher than $500^{\circ}C$ are recently being gradually increased. To overcome the restriction in the use at high temperature of the existing Al thermal media, a new capsule with double thermal media composed of two kinds of materials such as Al-Ti and Al-graphite was designed and fabricated more advanced than the single thermal media capsule. At the irradiation test of the capsule, the temperature of the specimens successfully reached $700^{\circ}C$ and the integrity of Al, Ti and graphite material was maintained.

• Nuclear Engineering and Technology
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• 제48권5호
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• pp.1083-1095
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• 2016

The design of Prototype Gen-IV Sodium-Cooled Fast Reactor (PGSFR) has been developed and the validation and verification (V&V) activities to demonstrate the system performance and safety are in progress. In this paper, the current status of test activities is described briefly and significant results are discussed. The large-scale sodium thermal-hydraulic test program, Sodium Test Loop for Safety Simulation and Assessment-1 (STELLA-1), produced satisfactory results, which were used for the computer codes V&V, and the performance test results of the model pump in sodiumshowed good agreement with those in water. The second phase of the STELLA program with the integral effect tests facility, STELLA-2, is in the detailed design stage of the design process. The sodium thermal-hydraulic experiment loop for finned-tube sodium-to-air heat exchanger performance test, the intermediate heat exchanger test facility, and the test facility for the reactor flow distribution are underway. Flow characteristics test in subchannels of a wire-wrapped rod bundle has been carried out for safety analysis in the core and the dynamic characteristic test of upper internal structure has been performed for the seismic analysis model for the PGSFR. The performance tests for control rod assemblies (CRAs) have been conducted for control rod drive mechanism driving parts and drop tests of the CRA under scram condition were performed. Finally, three types of inspection sensors under development for the safe operation of the PGSFR were explained with significant results.

• Nuclear Engineering and Technology
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• 제55권6호
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• pp.2047-2052
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• 2023

Risk-informed approach has been widely applied in the safety design, regulation, and operation of nuclear reactors. It has been commonly accepted that risk-informed design optimization should be used in the innovative reactor designs to make nuclear system highly safe and reliable. In spite of the risk-informed approach has been used in some advanced nuclear reactors designs, such as Westinghouse IRIS, Gen-IV sodium fast reactors and lead-based fast reactors, the process of risk-informed design of nuclear reactors is hardly to carry out when passive system reliability should be integrated in the framework. A practical method for new passive safety reactors based on probabilistic safety assessment (PSA) and passive system reliability analyze linking is proposed in this paper. New three-dimension frequency-consequence curve based on risk concept with three variables is used in this method. The proposed method has been applied to the determination optimization of design options selection in a 10 MWth lead-based research reactor(LR) to obtain one optimized system design in conceptual design stage, using the integrated reliability and probabilistic safety assessment program RiskA, and the computation resources and time consumption in this process was demonstrated reasonable and acceptable.

• 한국축산식품학회지
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• 제37권3호
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• pp.464-468
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• 2017

The identification of pork in commercially processed meats is one of the most crucial issues in the food industry because of religious food ethics, medical purposes, and intentional adulteration to decrease production cost. This study therefore aimed to develop a method for the detection of pork adulteration in meat products using primers specific for pig mitochondrial DNA. Mitochondrial DNA sequences for pig, cattle, chicken, and sheep were obtained from GenBank and aligned. The 294-bp mitochondrial DNA D-loop region was selected as the pig target DNA sequence and appropriate primers were designed using the MUSCLE program. To evaluate primer sensitivity, pork-beef-chicken mixtures were prepared as follows: i) 0% pork-50% beef-50% chicken, ii) 1% pork-49.5% beef-49.5% chicken, iii) 2% pork-49% beef-49% chicken, iv) 5% pork-47.5% beef-47.5% chicken, v) 10% pork-45% beef-45% chicken, and vi) 100% pork-0% beef-0% chicken. In addition, a total of 35 commercially packaged products, including patties, nuggets, meatballs, and sausages containing processed chicken, beef, or a mixture of various meats, were purchased from commercial markets. The primers developed in our study were able to detect as little as 1% pork in the heat treated pork-beef-chicken mixtures. Of the 35 processed products, three samples were pork positive despite being labeled as beef or chicken only or as a beef-chicken mix. These results indicate that the developed primers could be used to detect pork adulteration in various processed meat products for application in safeguarding religious food ethics, detecting allergens, and preventing food adulteration.

• 한국임상수의학회지
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• 제27권5호
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• pp.501-507
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• 2010

본 연구는 국내 타일레리아에서 주요항원단백질(major surface protein) 유전자의 다양성을 분석해 보고자 수행되었다. 나아가 Msp 유전자의 다양성과 타일레리아의 병원성과의 관계도 분석하였다. 제주에 있는 목장으로부터 총 177마리의 한우 혈액을 공시재료로 사용하여 혈액검사와 18S rRNA를 표적으로 하는 PCR을 실행하였다. 그 후, 타일레리아 18S rRNA에 양성인 28마리 (16마리 빈혈군과 12마리의 정상군)를 무작위로 선발하여 Msp유전자의 염기 서열을 반복하여 분석하였다. 총 56개의 염기서열 결과는 다변성 부위(517-571 bp)에 따라 크게 type I에서 type V까지 5가지 형태로 나눌 수 있었는데, 이는 유전자은행(GenBank)에 등록되어 있는 다음의 유전자와 98.9% 이상 일치하였다 (Theileria spp. from China-EU584237; T. sergenti from China-DQ078264; Theileria spp. from Thailand-AB081329; Theileria spp. from Japan-AB218442; T. sergenti from Japan-AB016280). 그 분포는 22, 15, 9, 8, 2개가 각각 type I에서 V까지 분포하였고 빈혈과 관계없이 type I이 가장 많이 나타나는 것으로 밝혀졌다(37.5%의 빈혈군과 41.7%의 정상군). 나머지 type중에서는 type II가 빈혈군에서 가장 많이(37.5%) 나타났으며, 반면 type IV는 정상군에서 많이 (25%) 나타났다. 본 연구는 국내 타일레리아 Msp유전자의 다양성을 밝히는데 좋은 자료로 활용될 수 있을 것이다.

• Nuclear Engineering and Technology
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• 제39권1호
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• pp.31-42
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• 2007

Energy supply is increasingly showing up as a major issue for electricity supply, transportation, settlement, and process heat industrial supply including hydrogen production. Nuclear power is part of the solution. For electricity supply, as exemplified in Finland and France, the EPR brings an immediate answer; HTR could bring another solution in some specific cases. For other supply, mostly heat, the HTR brings a solution inaccessible to conventional nuclear power plants for very high or even high temperature. As fossil fuels costs increase and efforts to avoid generation of Greenhouse gases are implemented, a market for nuclear generated process heat will be developed. Following active developments in the 80's, HTR have been put on the back burner up to 5 years ago. Light water reactors are widely dominating the nuclear production field today. However, interest in the HTR technology was renewed in the past few years. Several commercial projects are actively promoted, most of them aiming at electricity production. ANTARES is today AREVA's response to the cogeneration market. It distinguishes itself from other concepts with its indirect cycle design powering a combined cycle power plant. Several reasons support this design choice, one of the most important of which is the design flexibility to adapt readily to combined heat and power applications. From the start, AREVA made the choice of such flexibility with the belief that the HTR market is not so much in competition with LWR in the sole electricity market but in the specific added value market of cogeneration and process heat. In view of the volatility of the costs of fossil fuels, AREVA's choice brings to the large industrial heat applications the fuel cost predictability of nuclear fuel with the efficiency of a high temperature heat source tree of Greenhouse gases emissions. The ANTARES module produces 600 MWth which can be split into the required process heat, the remaining power drives an adapted prorated electric plant. Depending on the process heat temperature and power needs, up to 80% of the nuclear heat is converted into useful power. An important feature of the design is the standardization of the heat source, as independent as possible of the process heat application. This should expedite licensing. The essential conditions for success include: ${\bullet}$ Timely adapted licensing process and regulations, codes and standards for such application and design ${\bullet}$ An industry oriented R&D program to meet the technological challenges making the best use of the international collaboration. Gen IV could be the vector ${\bullet}$ Identification of an end user(or a consortium of) willing to fund a FOAK

• 방사성폐기물학회지
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• 제5권4호
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• pp.339-350
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• 2007

전세계 주요 원자력선진국들의 사용후핵연료 처리에 대한 기술 및 정책현황을 알아보고 향후 우리나라의 연구방향을 제시해 보았다. 재처리 정책을 가진 소위 핵연료주기 국가들은 최근 선진핵 연료주기기술에 기초한 새로운 사용후핵 연료 관리정책을 발표하였다. 그 정책은 사용후핵연료 내에 함유된 우라늄 또는 초우란 원소들을 재순환하고 고독성의 방사성 물질 및 장반감기를 가진 물질들을 소멸하거나 단반감기 원소로 변환하는데 초점을 맞추고 있다. 이러한 정책은 원자력의 자원 활용성을 높일 뿐만 아니라, 영구 처분할 고준위폐기물의 양을 감소시켜 궁극적으로 원자력의 지속가능성을 높여 준다. PUREX 방법에 기초한 습식재처리를 우선순위로 선택한 대부분의 국가들은 이 습식방법이 건식방법에 비해 실용화에 앞서 있음을 그 선택 의 근거로 든다. 그러나 습식방법은 건식에 비해 핵확산저항성 측면에서 더욱 민감하다. 왜냐하면 이 습식방법은 약간의 공정수정에 의해 순수 플루토늄을 회수 할 수 있기 때문이다. 반면에 아직까지 실용화 단계까지는 도달해 있지 않지만 고온 용융염을 사용하는 Pyroprocess와 같은 건식처리 방법은 순수한 플루토늄을 회수 할 수 없어서 핵비확산성 측면에서 유리하며, 제4세대 원자로로 고려되는 고속로의 핵연료주기 등에도 여러 가지 이점을 가지고 있다. 따라서 우리나라의 경우 현재 이 Pyroprocess에 대한 연구가 활발히 진행되고 있다.