• 제목/요약/키워드: Leak rate

검색결과 264건 처리시간 0.033초

The effect of atrophied pancreas as shown in the preoperative imaging on the leakage rate after pancreaticoduodenectomy

  • Ashraf Imam;Harbi Khalayleh;Meni Brakha;Ariel A. Benson;Naama Lev-Cohain;Gidon Zamir;Abed Khalaileh
    • 한국간담췌외과학회지
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    • 제26권2호
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    • pp.184-189
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    • 2022
  • Backgrounds/Aims: The soft texture of the pancreas parenchyma may influence the incidence of pancreatic leakage after pancreaticcoduodenectomy (PD). One possible method to assess pancreatic texture and atrophy, is via computed tomography (CT) scan of the abdomen. The purpose of our study was to evaluate the relation between the preoperative CT scan and the incidence of pancreatic fistula after PD. Methods: A retrospective single-center study including patients who underwent PD for a benign and malignant tumor of the periampullary region between the years 2000 and 2016. Demographic and imaging data were analysed and a correlation with the post-operative leak was evaluated. Results: Pancreatic leak was documented in 34 out of 154 (22.1%) patients. All the leakage cases occurred in the preserved pancreas group (33.1% of the total preserved pancreas group alone). No leak was documented in the atrophic pancreas group. This difference between the two groups was found to be statistically significant (p ≤ 0.00001). Conclusions: Atrophic pancreas in the preoperative CT scan may be protective against leakage after PD. These findings may help the surgeon to risk stratify patients accordingly. In addition, the findings suggest that patients with a preserved pancreas may require more protective methods to prevent leakage.

Leak rate 측정 기술지원

  • 임인태;신용현;홍승수;임종연;성대진;김정형;정광화
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2001년도 제21회 학술발표회 초록집
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    • pp.115-115
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    • 2001
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국제공동연구 PARTRIDGE를 통한 확률론적 건전성 평가 기술 개발 현황 (Current Status of an International Co-Operative Research Program, PARTRIDGE (Probabilistic Analysis as a Regulatory Tool for Risk-Informed Decision GuidancE))

  • 김선혜;박정순;김진수;이진호;윤은섭;양준석;이재곤;박홍선;오영진;강선예;윤기석;박재학
    • 한국압력기기공학회 논문집
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    • 제9권1호
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    • pp.62-69
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    • 2013
  • A probabilistic assessment code, PRO-LOCA ver. 3.7 which was developed in an international co-operative research program, PARTRIDGE was evaluated by conducting sensitivity analysis. The effect of some variables such as simulation methods (adaptive sampling, iteration numbers, weld residual stress model), crack features(Poisson's arrival rate, maximum numbers of cracks, initial flaw size, fabrication flaws), operating and loading conditions(temperature, primary bending stress, earthquake strength and frequency), and inspection model(inspection intervals, detectable leak rate) on the failure probabilities of a surge line nozzle was investigated. The results of sensitivity analysis shows the remaining problems of the PRO-LOCA code such as the instability of adaptive sampling and unexpected trend of failure probabilities at an early stage.

중수로 원자로건물 총누설감시계통 시험 중지에 따른 리스크 영향 평가 (Risk Assessment for Abolition of Gross Containment Leak Monitoring System Test in CANDU Design Plant)

  • 배연경;나장환;방기인
    • 한국안전학회지
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    • 제30권5호
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    • pp.123-130
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    • 2015
  • Wolsong Unit 2,3&4 has been performing a containment integrity test during power operation. This test could impact to the safe operation during test. If an accident occurs during pressure dropping phase, reactor trip can be delayed because of the increased pressure difference which causes a time delay to reach the trip set-point. On the contrary, if an accident occurs during pressure increasing phase, reactor trip could be accelerated because the pressure difference to the trip set-point decrease. Point Lepreau nuclear power plant, which installed GCLMS (Gross Containment Leakage Monitoring System) in 1990, has discontinued the test since 1992 due to these adverse effects. Therefore, we evaluated the risk to obviate the GCLMS test based on PWR's ILRT (Integrated Leak Rate Test) extension methodologies. The results demonstrate that risk increase rate is not high in case of performing only ILRT test at every 5 years instead of doing GCLMS test at every 1.5 years. In addition, the result shows that GCLMS test can be removed on a risk-informed perspective since risk increasement is in acceptable area of regulatory acceptance criteria.

기밀성 분석을 통한 RFID 태그 패키지 에폭시 몰딩 연구 (A Study on the RFID Tag Package Epoxy Molding through Leak Detection)

  • 반창우;홍석기;장동영
    • 한국생산제조학회지
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    • 제21권2호
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    • pp.297-304
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    • 2012
  • Recently RFID (Radio Frequency Identification) technology advances in wireless communication technologies are bringing new challenges. But RFID tag packaging technology has been lagging compared to the demand, so this technology is being required to improve reliability. In this paper, reliability comparison among 11 types of most commonly used epoxy molding in electrical/electronic components packaging has been made through analysis of confidentiality using a humidity sensor. Consequently, the variation of moisture penetration time causes has been verified by the changes in molding thickness for 3 types of epoxy, and from the result, the best experimental results were observed in terms of confidentiality. Moreover we have been confirmed the relationship between confidentiality, the molding thickness, and thermal property of epoxy through thermal analysis.

LNG 배관 시스템용 1인치 글로브 밸브 개발 및 성능실험 (Development and Performance Test on the 1-Inch Glove Valve for the LNG Piping System)

  • 이중섭;이치우
    • 한국기계가공학회지
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    • 제16권1호
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    • pp.9-16
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    • 2017
  • This study describes the development of a 1-inch cryogenic glove valve for an LNG pumping system and localization development achieved through the performance test. The cryogenic valve used in the LNG pumping system plays an important role in maintaining a flow rate by LNG transportation. This trial manufactured goods, which was achieved through reverse engineering and developing the assembly process. The result of the leak test satisfied the internal pressure condition using the 78-bar normal temperature test and maintained the anti-leakage condition. Also, the result of the cryogenic leak test (BS 6364: low temperature test procedure) maintained anti-leakage at -196 and 52 bar, which satisfied the test standards.

베이즈 분류기를 이용한 수냉식 냉동기의 고장 진단 방법에 관한 실험적 연구 (An Experimental Study on Fault Detection and Diagnosis Method for a Water Chiller Using Bayes Classifier)

  • 이흥주;장영수;강병하
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2008년도 하계학술발표대회 논문집
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    • pp.36-41
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    • 2008
  • Fault detection and diagnosis(FDD) system is beneficial in equipment management by providing the operator with tools which can help find out a failure of the system. An experimental study has been performed on fault detection and diagnosis method for a water chiller. Bayes classifier, which is one of classical pattern classifiers, is adopted in deciding whether fault occurred or not. FDD algorithm can detect refrigerant leak failure, when 20% amount of charged refrigerant for normal operation leaks from the water chiller. The refrigerant leak failure caused COP reduction by 6.7% compared with normal operation performance. When two kinds of faults, such as a decrease in the mass flow rate of cooling water and temperature sensor fault of cooling water inlet, are detected, COP is a little decreased by these faults.

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HCVT 구현 가능성 평가를 위한 해석모델 개발 및 특성검토 (Developing Analysis Model for Evaluation of HCVT Materialization Possibility, and Examining It's Characteristics)

  • 노대경;정동수;장주섭
    • 한국자동차공학회논문집
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    • 제24권1호
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    • pp.39-46
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    • 2016
  • This paper reviews design validity before manufacturing HCVT prototype through simulation. The component part is being devided, modeled and checked if it works well to an designer's original intent about some active modes. Also, the dynamic characteristic is examined how it changes according to alteration of pressure, friction and leak rate. Finally, HCVT design plan is being confirmed if it could be materialized through those analysis.