• Title/Summary/Keyword: 10CFR20

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Preliminary Shielding Analysis of the Concrete Cask for Spent Nuclear Fuel Under Dry Storage Conditions (건식저장조건의 사용후핵연료 콘크리트 저장용기 예비 방사선 차폐 평가)

  • Kim, Tae-Man;Dho, Ho-Seog;Cho, Chun-Hyung;Ko, Jae-Hun
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.4
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    • pp.391-402
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    • 2017
  • The Korea Radioactive Waste Agency (KORAD) has developed a concrete cask for the dry storage of spent nuclear fuel that has been generated by domestic light-water reactors. During long-term storage of spent nuclear fuel in concrete casks kept in dry conditions, the integrity of the concrete cask and spent nuclear fuel must be maintained. In addition, the radiation dose rate must not exceed the storage facility's design standards. A suitable shielding design for radiation protection must be in place for the dry storage facilities of spent nuclear fuel under normal and accident conditions. Evaluation results show that the appropriate distance to the annual dose rate of 0.25 mSv for ordinary citizens is approximately 230 m. For a $2{\times}10$ arrangement within storage facilities, rollover accidents are assumed to have occurred while transferring one additional storage cask, with the bottom of the cask facing the controlled area boundary. The dose rates of 12.81 and 1.28 mSv were calculated at 100 m and 230 m from the outermost cask in the $2{\times}10$ arrangement. Therefore, a spent nuclear fuel concrete cask and storage facilities maintain radiological safety if the distance to the appropriately assessed controlled area boundary is ensured. In the future, the results of this study will be useful for the design and operation of nuclear power plant on-site storage or intermediate storage facilities based on the spent fuel management strategy.

원자력分野에서의 破壞力學 現況 -법적 요구사항을 중심으로 (II)-

  • 송달호;손갑헌
    • Journal of the KSME
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    • v.20 no.6
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    • pp.457-467
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    • 1980
  • 가동중조사(ISI)에 적용되는 ASME-MI 의 1974년 Edition에 ISI시 검출된 흠함을 평가하는 절 차가 제시되었다는 것은 이미 언급한 바 있다. 가동중검사의 개념은 ASME-III에 따라 건설된 부품이라 하더라도 원자력발전소의 온 수명기간동안 또는 정해진 수명기간동안 재료 내부에 흠 함이 전혀 생기지 않는다거나 또는 성장하지 않는다고 볼 수 없다는데 에 근거를 둔 것이다. 즉, 부품을 건설할 때 ASME-III의 규정에 따라 수행한 비파괴시험(nondestructive examination)에 의하여 합격된 부품이라 할지라도 시험방법의 유효성 및 합격기준등에 의하여 발견되지 않았 거나, 발견되었더라도 합격된 흠합등이 있을 수 있다. 이러한 흠함들이 원자로의 가동과 더불어 성장하거나, 또는 부품의 사용조건에 따라 흠함이 새로이 발생할 경우는 RCPB의 구조적 건전성 및 안정성은 위협을 받게된다. 이에 대처하기 위하여 원자력발전소의 전수명기간의 통하여 정 기적으로 ISI를 수행해 줄 것이 10CFR50의 50, 55a, "Codes and Standards"에 법적으로 명문 화되어 있다. ISI 시발견된 흠함은 그 크기를 평가하여 합격기준을 초과하는 경우에는, 흠함의 제거(removal), 항리(repair), 부품의 대체(replacement), 또는 파괴력학적인 해석에 의하여 그러한 흠함이 구조건 안전성을 손상시키지 않는다는 것을 입증해 주어야 한다. ISI 시에 검출된 흠함을 평가하고 파괴력학적으로 해석하는 규정으로서 ASME-XI에 명시된 절차는 다음과 같다.차는 다음과 같다.

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A Study on QTG(Qualification Test Guide) Generation for a Flight Training Device to be Qualifiable at FAA Level 5 (X-Plane 기반 비행훈련장치의 FAA Level 5 FTD(Flight Training Device) 인증을 위한 QTG(Qualification Test Guide) 생성방법 연구)

  • Kim, Il-Woo;Park, TaeJun;Yoon, SukJun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.12
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    • pp.1035-1042
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    • 2016
  • By using commercial flight simulation game engine, X-Plane, we have studied QTG(Qualification Test Guide) generation that can satisfy FTD level 5. Flight model is SR-20 of Cirrus. In list of QTG, There are some items to measure control forces. therefore, we have installed CLS(Control Loading System) to flight control devices in order to make it possible to measure control forces. We made Autopilot function externally to make flight model in trim conditions because X-Plane don't provide internal trim routine function. In addition to develop an algorithm, it can automatically perform the test. To avoid the inconvenience to control as it was to be carried out in same conditions. In case of FTD level 5, it is possible to use alternative data sources not only real flight data. By using these alternative data sources, all test results satisfy a scope given by CFR Part 60.

Development of AAB (Algorithm-Aided BIM) Based 3D Design Bases Management System in Nuclear Power Plant (Algorithm-Aided BIM 기반 원전 3차원 설계기준 관리시스템 개발)

  • Shin, Jaeseop
    • Korean Journal of Construction Engineering and Management
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    • v.20 no.2
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    • pp.28-36
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    • 2019
  • The APR1400 (Advanced Power Reactor 1400MW) nuclear power plant is a large-scale national infrastructure facility with a total project cost of 8.6 trillion won and a project period of 10 years or more. The total project area is about 2.17 million square meters and consists of more than 20 buildings and structures. And the total number of drawings required for construction is about 65,000. In order to design such a large facility, it is important to establish a design standard that reflects the design intent and can increase conformity between documents (drawings). To this end, a design bases document (DBD) reflecting the design bases that extracted in regulatory requirements (e.g. 10CFR50, Korean Law, etc.) is created. However, although the design bases are important concepts that are a big framework for the whole design of the nuclear power plant, they are managed in 2-dimensional by the experts in each field fragmentarily. Therefore, in order to improve the usability of building information, we developed BIM(Building Information Model) based 3-dimensional design bases management system. For this purpose, the concept of design bases information layer (DBIL) was introduced. Through the simulation of developed system, design bases attribute and element data extraction for each DBIL was confirmed, and walls, floors, doors, and penetrations with DBIL were successfully extracted.

Particle Filtration Efficiency Testing of Sterilization Wrap Masks

  • Chau, Destiny F.;O'Shaughnessy, Patrick;Schmitz, Michael L.
    • Journal of Preventive Medicine and Public Health
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    • v.54 no.1
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    • pp.31-36
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    • 2021
  • Objectives: Non-traditional materials are used for mask construction to address personal protective equipment shortages during the coronavirus disease 2019 (COVID-19) pandemic. Reusable masks made from surgical sterilization wrap represent such an innovative approach with social media frequently referring to them as "N95 alternatives." This material was tested for particle filtration efficiency and breathability to clarify what role they might have in infection prevention and control. Methods: A heavyweight, double layer sterilization wrap was tested when new and after 2, 4, 6, and 10 autoclave sterilizing cycles and compared with an approved N95 respirator and a surgical mask via testing procedures using a sodium chloride aerosol for N95 efficiency testing similar to 42 CFR 84.181. Pressure testing to indicate breathability was also conducted. Results: The particle filtration efficiency for the sterilization wrap ranged between 58% to 66%, with similar performance when new and after sterilizing cycles. The N95 respirator and surgical mask performed at 95% and 68% respectively. Pressure drops for the sterilization wrap, N95 and surgical mask were 10.4 mmH2O, 5.9 mmH2O, and 5.1 mmH2O, respectively, well below the National Institute for Occupational Safety and Health limits of 35 mmH2O during initial inhalation and 25 mmH2O during initial exhalation. Conclusions: The sterilization wrap's particle filtration efficiency is much lower than a N95 respirator, but falls within the range of a surgical mask, with acceptable breathability. Performance testing of non-traditional mask materials is crucial to determine potential protection efficacy and for correcting misinterpretation propagated through popular media.

Repair and Replacement Methodology for Electrical Equipment Used in Nuclear Power Plants (원자력발전소 전기기기의 보수, 교체 방법론)

  • Park, Chulhee;Park, Wan-gyu;Lee, Manbok;Kim, Choon-sam
    • Proceedings of the KIPE Conference
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    • 2018.07a
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    • pp.177-179
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    • 2018
  • After Fukushima nuclear accident at 2011, nuclear industrial has been focused on operation and maintenance phase, not design and construction phase. Continued good operating performance of nuclear power plants has been the best critical issue to nuclear utilities. Replacement for complete components as well as parts of components is being procured because nuclear utilities must maintain safety and reliability of operating nuclear power plants. However, many suppliers and manufacturers are giving up a nuclear quality assurance program under reduction in new construction of nuclear power plants. It is able to be increased difficulty in procuring spare parts to support operations and maintenance of nuclear power plants. Over 20% of nuclear power plant equipment in some countries is obsolete. Owing to obsolescence of nuclear safety-related items and/or withdrawing a nuclear quality assurance program of suppliers and manufactures, some replacement item and part might be procured to the item not covered by appendix B to USNRC 10 CFR Part 50. Under various methods of the nuclear repair and replacement methodology, utilities are supposed to establish a typical program for a repair and replacement of an electrical equipment and its parts in conjunction with a nuclear quality assurance. Concerning this typical program, this study suggests the repair and replacement methodology of electrical equipments used in nuclear power plants by procurement of a power supply, based on nuclear regulations, codes, standards, guidelines, specific and general technical information, etc..

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Preparation of tomato Kimchi and its characteristics (토마토 김치의 제조 및 특성)

  • Kim, Eun-Jung;Hahn, Young-Sook
    • Korean journal of food and cookery science
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    • v.22 no.4 s.94
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    • pp.535-544
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    • 2006
  • Kimchi is well Down for its taste and health function. However, recently Kimchi consumption has been falling because of its salty taste, spice flavor and pungency. This study was aimed to prepare a less salty and more mildly flavored Kimchi with the addition of tomato which contains a red color similar to that of the hot pepper used in traditional kimchi preparation has functionality. The pH, total acidity, color, texture, microbes, sugar, salt, Na and K content of the tomato kimchi were measured. The total amount of phenolic compounds of the tomato kimchi was five times higher than that of traditional kimchi without tomato. A sensory evaluation of the tomato kimchi demonstrated its higher acceptability in overall color, fresh flavor and hot taste but no difference in acidity compared to the traditional kimchi.