• Title/Summary/Keyword: event study

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A Study on FTA of Off-Site Packaged Hydrogen Station (Off-Site 패키지형 수소충전소의 FTA 분석)

  • SEO, DOO HYOUN;KIM, TAE HUN;RHIE, KWANG WON;CHOI, YOUNG EUN
    • Journal of Hydrogen and New Energy
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    • v.31 no.1
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    • pp.73-81
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    • 2020
  • For the fault tree analysis (FTA) analysis of the packaged hydrogen filling station, the composition of the charging station was analyzed and the fault tree (FT) diagram was prepared. FT diagrams were created by dividing the causes of events into external factors and internal factors with the hydrogen event as the top event. The external factors include the effects of major disasters caused by natural disasters and external factors as OR gates. Internal factors are divided into tube tailer, compressor & storage tank, and dispenser, which are composed of mistakes in operation process and causes of accidents caused by parts leakage. In this study, the purpose was to improve the hydrogen station. The subjects of this study were domestic packaged hydrogen stations and FTA study was conducted based on the previous studies, failure mode & effect analysis (FMEA) and hazard & operability study (HAZOP). Top event as a hydrogen leaking event and constructed the flow of events based on the previous study. Refer to "Off shore and onshore reliability data 6th edition", "European Industry Reliability Data Bank", technique for human error rate prediction (THERP) for reliability data. We hope that this study will help to improve the safety and activation of the hydrogen station.

Development of the Event Type Analysis System (ETAS) for the Accident Evaluation in Nuclear Power Plants (원전사고 평가를 위한 원전 사건유형분석 시스템(ETAS) 개발)

  • Choi, Young Hwan;Kim, Young Mi
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.5 no.2
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    • pp.35-39
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    • 2009
  • In this study, Event Type Analysis System (ETAS) is developed for the accident evaluation in nuclear power plant. The ETAS system can be used in supporting regulator and/or operator under event situation in nuclear power plants. The ETAS system can categorize the all transient events to 3 categories such as Down-2000, Down-2173, and Slow Fluctuation. We develop the program structure for ETAS system and web-based ETAS system. The ETAS system will be used as sub module of Knowledge-Based Event Evaluation Network (K-EvENT) which is developing for the against the accident in nuclear power plants.

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Development of Event Corrective Action Supporting System (ECAS) in Nuclear Power Plant (원전 사고처리 지원시스템(ECAS) 개발)

  • Choi, Young Hwan;Kim, Yopng Mi;Ko, Han Ok
    • Transactions of the Korean Society of Pressure Vessels and Piping
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    • v.5 no.2
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    • pp.40-44
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    • 2009
  • In this study, Event Corrective Action Supporting System (ECAS) is developed for the accident evaluation in nuclear power plant. The ECAS system can be used in supporting regulator and/or operator under event situation in nuclear power plants. The ECAS system consists of 5 modules including failure location module, failure analysis module, failure integrity evaluation module, system vulnerability evaluation module, and reporting and operating experience feedback module. The ECAS system will be used as sub module of Knowledge-Based Event Evaluation Network (K-EvENT) which is developing for the against the accident in nuclear power plants.

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A Study of Heavy Snow event caused Runway closed (활주로 폐쇄를 야기한 대설 사례 연구)

  • Kim, Young-Chul
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.21 no.4
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    • pp.106-111
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    • 2013
  • The heavy snow event occurred on JAN 4, 2010 brought huge disaster such as Gimpo International Airport runway closed, heavy delays of other airport, and property damage of 16 billion won. Though this heavy snow event is involved in the general synoptic scale heavy snow forecast, it recorded too much snow amount and longer duration than expected. To explain this unusual event, we used the conveyor belt theory. By combining the synoptic scale heavy snow forecast and the conveyor belt theory, the characteristics of heavy snow event was well explained.

A Study on the Efficiency of the EPCIS using Simulation (시뮬레이션을 이용한 EPCIS의 효율화 방안에 관한 연구)

  • Li, Zhong-Shi;Lee, Chang-Ho
    • Journal of the Korea Safety Management & Science
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    • v.12 no.4
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    • pp.169-174
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    • 2010
  • EPCIS(EPC Information Services) system is a core component of EPCglobal Architecture Framework offering information of the freights, the time of awareness and the location of awareness on the EPCglobal Network. The role of EPCIS is to exchange information based on EPC. There are four kinds of event data which are object event data, aggregation event data, quantity event data, and transaction event data. These EPCIS events data are stored and managed in EPCIS repository. This paper deals with the method which diversifies the data flow load of intensive EPCIS events and effectively manages EPCIS repository for exchanging data smoothly. In order to verify a effectiveness, we measure the performance of the system using a simulation by comparing the existing method with the suggested method.

Study of Analysis Software for Event Recorder in High Speed Railway (고속전철용 Event Recorder를 위한 분석도구 소프트웨어 연구)

  • Song, Gyu-Youn;Lee, Sang-Nam;Ryu, Hee-Moon;Kim, Kwang-Yul;Han, Kwang-Rok
    • Proceedings of the KSR Conference
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    • 2009.05b
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    • pp.341-347
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    • 2009
  • In high speed railway, event recorder system stores a train speed and the related data for train operation in real time. Using those information, we can analysis the train operation and the reason of train accident. Analysis software gets the stored data from Event Recorder and shows the status of various signals related with train operation. Using it, also we can analysis the train operation before and after the given time. In this paper we propose the analysis software to show and analysis the operation of high speed train. The method of transferring the stored data from Event Recorder into Analysis Software is proposed. We develop the efficient procedure to store the transferred data into analysis system. Also the effective method to show the store data and to analysis them is studied for finding the cause of train accident.

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Development of Underwater Hull Search Time Prediction Model with Discrete Event Simulation (이산사건 시뮬레이션을 이용한 수중 선체 탐색 시간 예측 모델 개발)

  • Joopil Lee;Seung-Ho Ham
    • Journal of the Society of Naval Architects of Korea
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    • v.61 no.3
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    • pp.152-160
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    • 2024
  • In the event of a maritime accident, search plans have traditionally been planned using experiential methods. However, these approaches cannot guarantee safety when the scale of a maritime accident increases. Therefore, this study proposes a model utilizing discrete event simulation (DES) to predict the diving time for compartment searches of a ship located on the seabed. The discrete event simulation model was created by applying the DEVS formalism. The M/V Sewol sinking was used as an example to simulate how to effectively navigate compartments of different sizes. The simulation results showed the optimal dive time with the number of decompression chambers needed to navigate the compartment as a variable. Based on this, we propose a methodology for efficient navigation planning while ensuring diver safety.

ISO9000 Certification Effect: Evidence from China

  • Liu, Yumin
    • International Journal of Quality Innovation
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    • v.9 no.3
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    • pp.15-27
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    • 2008
  • As a sign of international quality system, ISO9000 certification has been adopted by more and more enterprises. In recent five years, there have been 560,000 certified companies in Europe and America, and there have been more than 390,000 ones in China. It has being attracted many quality scholars' attentions whether ISO9000 certification can bring more benefits to certified companies or not. This paper investigates the ISO9000 certification effect on market performance by the samples from Chinese list companies in shanghai stock exchange. Considering ISO9000 certification as an event, a certification effect model will be set up by means of the event study method, which takes abnormal return rate as a basic indicator to measure the ISO9000 certification effect on Chinese market performance in different event times. Investigation results show that the Chinese certified companies have some positive effects on market performance in the short term. From a long standpoint, the relation between certification and performance has a positive trend.

Implicit Arguments in English Middles

  • Chung, Taegoo
    • Korean Journal of English Language and Linguistics
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    • v.1 no.2
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    • pp.331-347
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    • 2001
  • In this study I investigate two implicit arguments in English middles: discharged argument and event argument. I argue that in middle formation external argument is discharged and event argument is suppressed. The proposal can account for the problems with the previous studies (Williams 1981; Keyser and Reoper 1984: Roberts 1987: Fagan 1988, 1992: Chung 2000). When a middle derives from the corresponding transitive verb, the subject argument is discharged, being an implicit argument. Argument discharge is different from argument suppression in the passives and argument deletion in the ergatives. I also argue that event argument is suppressed in middle formation. Event argument suppression is supported by the following: (i) The transitive verbs are always eventive but the corresponding middles are stative, and (ii) the middles are underlyingly eventive, (iii) the middles are “adorned” by certain manner adverbials.

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Satisfaction of Korean Restaurant near World Cup Stadium (월드컵 경기장 주변 한식당의 고객만족도)

  • 강명숙
    • Culinary science and hospitality research
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    • v.8 no.2
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    • pp.117-132
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    • 2002
  • The world's greatest single event the 2002 World Cup, will be co-hosted by Korea and Japan. This will be the first time an interactional mesa-event is held in two countries simultaneously. Pertaining to every aspect, competition between the Korean foodservice industries will intensify in the near future. Generally, a sporting event contributes positively to n hosting county as well. For this reason we cannot expect the 2002 World Cup to be a complete success. A wrongly planned event could be a burden to our countries economy and create various negative effects. This study was prepared predominantly using field research methods including the collection of data through questionnaires. This study is based on a sample of 212 who have visiting Korean Restaurant near World Cup Stadium. These questionnaires were distributed by 5 students. This research us conducted from April 1 to 20, 2002 at Suwon.

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