• 시스템엔지니어링학술지
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• 제10권1호
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• pp.43-48
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• 2014

The door system for railway vehicles is the critical device directly influences on safety and satisfaction of passengers, Recently, electrical type of passenger door system is widely used for EMU type train instead of pneumatic type of passenger door system. The estimation of MTBF and failure rates for electrical type door system is essential. The manufacturor simply provides intrinsic reliability data for the railway operator. But actual reliability data based on operation and maintenance data is not complying with intrinsic reliability. In this study, operation and failure data associated with electrical door system were analyzed in order to determine actual MTBF and failure data. Intrinsic reliability data and service reliability data were studied to finallize much more practical and reliable actual reliability. Relax 2011 was used to predict intrinsic reliability and 217Plus model was also used to estimate of actual reliability data based on field data. Furthermore, it is necessary to keep studying on reliability prediction methodology and applying it in the field and doing research on improvement of reliability through feedback as well.

• 한국신뢰성학회지:신뢰성응용연구
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• 제13권4호
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• pp.241-252
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• 2013

Because of financial and safety concerns, there are needs for more accurate prediction of bridge behavior. Underestimation of the bridge load carrying capacity can have serious economic consequences, as deficient bridges must be repaired or rehabilitated. Therefore, the knowledge of the actual bridge behavior under live load may lead to a more realistic calculation of the load carrying capacity and eventually this may allow for more bridges to remain in service with or without minor repairs. The presented research is focused on the reliability evaluation of the actual load carrying capacity of existing bridges based on the field testing. Seventeen existing bridges were tested under truck load to confirm their adequacy of reliability. The actual response of existing bridge structures under live load is measured. Reliability analysis is performed on the selected representative bridges designed in accordance with AASHTO codes for bridge component (girder). Bridges are first evaluated based on the code specified values and design resistance. However, after the field testing program, it is possible to apply the experimental results into the bridge reliability evaluation procedures. Therefore, the actual response of bridge structures, including unintentional composite action, partial fixity of supports, and contribution of nonstructural members are considered in the bridge reliability evaluation. The girder distribution factors obtained from the tests are also applied in the reliability calculation. The results indicate that the reliability indices of selected bridges can be significantly increased by reducing uncertainties without sacrificing the safety of structures, by including the result of field measurement data into calculation.

• 한국멀티미디어학회논문지
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• 제19권2호
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• pp.300-307
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• 2016

Cloud computing that provide a elastic computing service is more complex compared to the existing computing systems. Accordingly, it has become increasingly important to maintain the stability and reliability of the computing system. And troubleshooting and real-time monitoring to address these challenges must be performed essentially. For these goals, the handling of the log data is needed, but this task in cloud computing environment may be more difficult compared to the traditional logging system. In addition, there are another challenges in order to have the admissibility of the collected log data in court. In this paper, we design secure logging service that provides the management and reliability of log data in a cloud computing environment and then analyze the proposed system.

• 대한전기학회논문지:전력기술부문A
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• 제49권4호
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• pp.143-151
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• 2000

Electric power distribution feeders are susceptible to faults caused by a variety of situations such as adverse weather conditions, tree contacts, equipment failure, accidents, etc. Distribution circuit faults result in a number of problems related to the reliability of service and customer power quality. In the distribution line, the permanent interruption of customer service resulting from a blown fuse or a recloser lockout was the only factor which was used to determine service reliability. On underground distribution line, the serving of cables by earth-moving equipment is a prevalent cause of faults and the most cable faults quickly develop into bolted current. we introduce th multi-circuit breaker coordination methods in the Underground Distribution Line.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.932-934
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• 1998

Electric power distribution feeders are susceptible to faults caused by a variety of situations such as adverse weather conditions, tree contacts, equipment failure, accidents, etc. Distribution circuit faults result in a number of problems related to the reliability of service and customer power quality. In the past, the permanent interruption of customer service resulting from a blown fuse or a recloser lockout was the only factor which was used to determine service reliability. So we developed KODAS(Korea Distribution Automation System) with successful and had fieid-testing of Distribution Automation System in last three years at Kang-dong Branch Office. In performing the project, KEPRI has gained valuable experience, through dealing with many difficult problem. This paper is depicted about the circuit breaker coordination problems in the Underground for the Distribution Automation Feeder.

• International Journal of Reliability and Applications
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• 제14권1호
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• pp.41-54
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• 2013

In this paper, cost analysis is conducted using inter-failure interval under renewable warranty subject to imperfect repair for multi-component system. One way to model the imperfect repair is to use the quasi-renewal process (Wang and Pham 1996). Two alternative quasi-renewal processes were suggested by Park and Pham (2010) using quasi-renewal process; first is an altered quasi-renewal process with random variable parameter and second is a mixed quasi-renewal process considering replacement service and repair service, simultaneously. In this study, we use the altered and mixed quasi-renewal processes and develop the warranty cost model to obtain the expected value of warranty cost and to help company make important decisions regarding the warranty policy. Numerical examples are used to demonstrate the applicability of the methodology derived in the paper.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2006년도 춘계학술대회
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• pp.473-478
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• 2006

Empirical analysis was based on the data of 692 hotel employees from Seoul and Gyung-gi province. To test the relationship between job characteristics and service quality, multiple regression analysis was applied, and hierarchial regression analysis(Cohen & Cohen, 1983) applied to test the moderating effects of gender and tenure. Multiple regressional analysis showed that job importance, job variety, and feedback had an positive impact on tangibility, reliability, responsiveness, assurance, empathy, but autonomy had a negative impact on tangibility, reliability, responsiveness, assurance. Hierarchical regressional analysis showed that gender had moderating effects on 4 relationships between job characteristics and service quality, and tenure had moderating effects on 3 relationships.

• 품질경영학회지
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• 제22권3호
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• pp.16-33
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• 1994

This paper developes a multiple-item scale instrument (called SHIPQUAL which is designed to measure the quality of shipping industry. The procedures of developing instrument were followed by recommendations on the developing measures of marketing constructs. We divided shipping service quality into 4 demensions (reliability, conformability, timely/completness, safety) by empirical study. These demensions and scales were varified through the assessment of reliability and validity. Finally, we suggested potential applications of the scale into the shipping industry.

• 한국컴퓨터정보학회논문지
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• 제25권3호
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• pp.97-107
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• 2020

본 연구는 서비스품질과 기술수용모델(TAM)이 고객만족에 미치는 영향에 관한 분석이며, 중국의 디디추싱 이용자를 대상으로 하였습니다. 본 연구의 조사는 온라인 설문 방식으로 9일 동안 총 414명을 조사하였고 유효한 응답은 314명이었다. 설문조사를 통해 수집된 데이터는 SPSS 24.0과 AMOS 18.0을 이용하여 분석하였다. 분석결과 학문적 시사점은 다음과 같다. 첫째, 디디추싱의 서비스품질은 기술수용모델(TAM)에 긍정적인 영향을 미치는 것으로 분석되었다. 둘째, 기술수용 모델은 태도와 고객만족에 긍정적인 영향을 미치는 것으로 나타났다. 셋째, 조절효과 분석결과, 태도와 고객만족은 신뢰의 정도에 따라서 부분적으로 영향을 미치는 것으로 분석되었다. 실무적인 시사점은 다음과 같다. 첫째, 고객들에게 서비스품질 요인을 제공할 필요가 있다. 둘째, 고객들에게 신뢰가 중요하다. 이러한 결과에 따라서 한계점과 향후방안들이 있다. 첫째, 표본의 다양성이 필요하다. 둘째, 차량유형에 따른 분석이 필요하다. 향후에는 세부적인 연구가 필요하다.

• 한국콘텐츠학회논문지
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• 제15권12호
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• pp.257-272
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• 2015

본 연구는 사회복지전담공무원 스스로가 인식하는 공공복지서비스 질 수준을 인구사회학적 특성에 따른 차이를 분석하여 더 나은 복지서비스 제공을 위한 대안을 모색하기 위한 것이다. 이를 위해 사회복지전담공무원 401명을 대상으로 복지서비스 질 5개 구성요소인 유형성(Tangibles), 신뢰성(Reliability), 대응성(Responsiveness), 공감성(Empathy), 보증성(Assurances)의 각 항목을 분석하였다. 분석결과 공공복지서비스 질의 수준을 인식하는데 있어서 연령에 따라 가장 큰 편차를 보여 주었고 주민과 가까운 일선 현장(시도> 시군구> 읍면동)일수록 복지서비스의 질 수준이 낮아졌다. 또한 신뢰성, 대응성, 공감성에 대해 다소 낮은 인식수준을 나타냈다. 사회복지전담공무원은 주민중심의 가치 지향적이고, 실천적인 복지현장의 사회복지사이자 공무원이다. 본 연구는 이들의 인식수준을 통하여 공공복지의 변화방향과 근본적인 전달체계의 방향성을 제시하여 주었다는 점에서 의의가 있다.