• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.179-184
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• 1997

지금까지 수행되었던 원자력발전소의 확률론적 안전성 평가 (Probabilistic Safety Assessment; PSA) 결과, 노심손상 빈도의 30% - 70%가 인간행위와 관련이 있는 것으로 밝혀져 PSA에서 인간행위를 적절히 다루는 것은 매우 중요하다. 특히 원자력발전소의 정지운전인 경우에는 자동으로 작동하는 계통이 거의 없어 고장수목(fault tree)과 사건수목(event tree)의 모델링에 많은 운전인 행위가 포함되기 때문에 노심손상 빈도와 관련이 있는 인간행위는 전출력 운전(full power operation)에 대한 PSA 결과의 경우보다 많은 것으로 나타났다. PSA에서 인간신뢰도분석(human reliability analysis)은 PSA의 논리구조인 고장수목과 사건수목에 모델링될 인간행위를 파악하고 정량화하는 것이다. 현재 인간신뢰도분석은 인간행위에 대한 데이타의 부족과 인간행위 자체의 다변성(variability)으로 인해 분석에 어려움이 있고 분석자의 주관성이 개입될 여지가 많은 실정이며, 이에 따라 분석 결과에는 많은 불확실성을 내포하게 된다. (중략)

• Journal of Microbiology and Biotechnology
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• v.28 no.9
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• pp.1542-1546
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• 2018

Bacterial canker in kiwifruit is caused by Pseudomonas syringae pv. actinidiae (Psa). In this study, the bacteriophage PPPL-1 effective against Psa was characterized. Belonging to the Podoviridae family, PPPL-1 was effective against most Psa strains as well as most Pseudomonas syringae pathovars. PPPL-1 carries a 41,149-bp genome with 49 protein coding sequences and is homologous to the previously reported phiPSA2 bacteriophage. The lytic activity of PPPL-1 was stable up to $40^{\circ}C$, within a range of pH 3-11 and under 365 nm UV light. These results indicate that the bacteriophage PPPL-1 might be useful to control Psa in the kiwifruit field.

• Nuclear Engineering and Technology
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• v.41 no.8
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• pp.1065-1072
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• 2009

As the use of software increases at nuclear power plants (NPPs), the necessity for including software reliability and/or safety into the NPP Probabilistic Safety Assessment (PSA) rises. This work proposes an application procedure of software reliability growth models (RGMs), which are most widely used to quantify software reliability, to NPP PSA. Through the proposed procedure, it can be determined if a software reliability growth model can be applied to the NPP PSA before its real application. The procedure proposed in this work is expected to be very helpful for incorporating software into NPP PSA.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.432-435
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• 1996

The performance of one-column isothermal PSA process is assessed by dynamic simulator, gPROMS. The four-step and five-step processes are compared. A five-step process is employed in order to show the effect of the addtional cocurrent depressurization step on the four-step PSA process. Two processes parameters, purity and recovery of SO$_{2}$ are used for the performance comparison. The results of dynamic simulation show that four-step process is superior to five-step process in recovery, but not in purity.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.05a
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• pp.91-97
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• 1994

본 연구의 목표는 제올라이트 분자체를 흡착제로 사용하여 99.99% 이상의 고순도 질소를 저렴하게 제조하는 PSA(Pressure Swing Adsorption)공정을 개발하고 상업화 설계 자료를 도출하는 것이다. PSA방법에 의한 질소제조는 기존의 심냉법보다 전력원단위가 낮을 뿐만 아니라 on-site방식으로 설치되어 운영되므로 수송경비를 절감할 수 있다. 이러한 장점 때문에 외국의 경우를 보면 PSA의 사용이 날로 증대되고 있다. 현재 국내에 설치중인 질소 PSA는 전량 수입에 의한 것이다. 따라서 본 연구에서 개발한 질소 PSA는 중소규모의 질소가스 사용처에 공급함으로써 에너지절감효과 뿐만아니라, 수입대체효과도 얻을 수 있다.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.850-855
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• 1998

소형 냉각재상실사고 발생 후 고압안전주입이 작동하지 않는 경우, 국내 원자력발전소의 확률론적 안전성평가 (Probabilistic Safety Assessment: PSA) 에서 고려한 일차측 급속냉각 (Aggressive Cool Down of Reactor Coolant System)의 수행 가능성에 대한 논란이 있다. PSA분석 결과에 의하면, 일차측 급속냉각을 위해서는 운전원 조치가 전체 노심손상빈도에 큰 영향을 주고 있음을 보여주지만, 현재 작성되어 있는 국내 원자력발전소의 비상 운전절차서에 따르면 PSA 모델시 가정된 성공기준으로 일차측 급속냉각의 수행에 실패할 가능성이 매우 높은 것으로 판단된다. 이에 따라 본 논문에서는 소형 냉각재상실사고로 인한 노심 손상빈도 측면에서 PSA에서 사용한 일차측 급속냉각 성공기준과 인간오류에 대하여 민감도분석을 수행하였다. 또한 열수력학적 분석을 통해 일차측 급속냉각의 타당성과 성공기준을 재검토했다. 이 결과 일차측 급속냉각의 수행 가능성 여부와 노심 손상빈도에 미치는 영향을 도출하였고 일차측 급속냉각의 성공적 수행을 위한 새로운 성공기준을 제시한다.

• Journal of Hydrogen and New Energy
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• v.27 no.6
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• pp.628-635
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• 2016

Natural gas reformed hydrogen is used as a fuel of fuel cell vehicle, PSA process is used for the purification of reformed hydrogen. In this study, the performance of CO adsorbent in PSA process was evaluated. Zeolite adsorbents used in the commercial PSA process is used. The physical and chemical properties of adsorbents were characterized using BET apparatus, XRD, and FE-SEM. The breakthrough apparatus modified from GC was used for the CO breakthrough experiment, the quantitative analysis of CO adsorption capacity was performed using CO breakthrough curve. Zeolite 10X and 13X showed superior CO adsorption capacity than activated alumina. The CO adsorption capacity of zeolite 10X is more than twice of zeolite 13X even the BET surface area is low. It seems that the presence of $Ca^{2+}$ cation in zeolite 10X is beneficial to the adsorption of CO.

• Journal of the Korean Society of Safety
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• v.14 no.1
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• pp.177-184
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• 1999

PSA(Probabilistic Safety Assessment) methodology is widely used on assessing the safety of Nuclear Power Plants(NPPs) quantitatively in the domestic nuclear field. Initiating event frequencies are absolutely needed to conduct PSA, and they considerably affect PSA results. There is no domestic database where domestic trip event cases are reflected, so they are used to assess the safety of NPPs that are from the foreign database. In this paper, operating experience data from the Korean NPPs was collected and analyzed for the trip event cases, which are necessary to determine the initiating events and their frequencies. Korean NPPs have experienced five of 16 initiating events, which we LOFW. LOCV, LOCCW, LOOP and GTRN as a result of analyzing the trip event cases. Initiating frequencies based on the domestic trip event cases are analyzed, and they are similar to that from the foreign database.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.412-415
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• 2009

This paper analyzes efficiency of photovoltaic(PV) tracking system using position solar algorithm(PSA). Solar location tracking system is needed for efficiently and intensively using PV system independent of environmental condition. PV tracking system of program method is presented a high tracking accuracy without the wrong operating in rapidly changed insolation by the clouds and atmospheric condition. Therefore, this paper analyzes efficiency of PV system using PSA algorithm for more correct position tracking of solar. Also, controlled altitude angle and azimuth angle by applied algorithm is compared with data of korea astronomy observatory. And this paper analyzes the tracking error and roves the validity of applied algorithm.

• Journal of Chest Surgery
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• v.45 no.5
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• pp.342-344
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• 2012

A persistent sciatic artery (PSA) is very rare congenital vascular anomaly which is present in 0.025% to 0.04% of the population by an angiographic study. A PSA is usually combined with aneurismal disease or thromboembolic events because of its arteriosclerosis and vessel wall degeneration. The treatments of symptomatic PSA are comprised of exclusion of PSA from circulation and bypass surgery for the lower limb. However, surgical treatment should be tailored to its anatomy and presentation. We report a successful treatment of PSA with distal thromboembolism by thromboembolectomy without bypass surgery.