• Journal of the Korea Society of Computer and Information
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• v.11 no.5 s.43
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• pp.9-18
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• 2006

Finite failure NHPP models presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing failure occurrence rates per fault. In this paper, Goel-Okumoto and Yamada-Ohba-Osaki model was reviewed, proposes the exponentiated exponential distribution reliability model, which maked out efficiency substituted for gamma and Weibull model(2 parameter shape illustrated by Gupta and Kundu(2001) Algorithm to estimate the parameters used to maximum likelihood estimator and bisection method, model selection based on SSE, AIC statistics and Kolmogorov distance, for the sake of efficient model, was employed. Analysis of failure using NTDS data set for the sake of proposing shape parameter of the exponentiated exponential distribution was employed. This analysis of failure data compared with the exponentiated exponential distribution model and the existing model (using arithmetic and Laplace trend tests, bias tests) is presented.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.6
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• pp.517-525
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• 2007

As usage of UAV becomes more common, a basic requirements on the system are changing. Existent system did function embodiment by major object, but current UAV puts bigger weight to availability. Therefore, all the advanced countries in UAV technologies put great efforts in reliability analysis techniques and source collection of system, and reflect the result in design. The authors are developing a flight control system for a UAV and using the reliability analysis techniques in the process. This paper introduces basic reliability analysis techniques and results of analysis for a small UAV flight control system that is developing present. The result plans efficiency enlargement UAV development and operation process.

• Proceedings of the Safety Management and Science Conference
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• 2000.05a
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• pp.427-434
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• 2000

본 연구에서는 품질기능전개(QFD)를 품질전개, 기술전개, 원가전개, 신뢰성전개로 구분하여 각 단계에서 실무적으로 고려해야 할 중요한 사항을 제안한다. 품질전개에서는VOC로 J.D.Power사의 시장품질조사 방법을 활용할 것을 제안하며 기술전개에서는 새로운 SPC 공정도와 작업표준 작성방안을 제안한다. 끝으로 신뢰성 전개에서는 BOM의 구조분석과 RBD, FTA 통합기능분석, FMEA의 체계적인 정리 등의 3단계 전개방안을 제안한다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.9 s.351
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• pp.120-127
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• 2006

In Korea the vehicle enforcement system(VES) detects speeding vehicle using two inductive loop detectors. And the speed reliability of theirs are evaluated through the analysis of image frame which is captured from video camera. This method is validated to evaluate VES on Korea Laboratory Accreditation Scheme(KOLAS) but it needs much time and expense for the analysis of image frame. Because the number of VES are increasing rapidly, the requirement of new evaluation method is necessary. On this paper, the tape switch sensor as a substitution of existing method was introduced and its application on the site are discussed. On the site test we compared the tape switch sensor on the speed measurement of vehicle with the video image frame. As a result we have founded that the tape switch sensor is evaluated to be feasible system on site in respect to measure the overspeed vehicle.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.1
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• pp.61-68
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• 1988

This study is intended to propose an approach to reliability-based safety evaluation as well as LRFR(Load and Resisitance Factor Rating) type capacity classification of military or civilian bridges based on the limit state models which are delived by incorporating all the uncertainties of resistance and load random variables including deterioration, and are used in a practical AFOSM (Advanced First Order Second Moment) method. The proposed methods for the assement of safety and load carrying capacity are applied for the evaluation of rating and classifications of several practical bridges against the crossing of military vehicles. Based on the observation of the numerical results, it can be concluded that the current NATO classification method which is based on the traditionl allowable stress concept can not provide real load carrying capacity but results in nominal classification, and therefore the reliability-based safety evaluation and LRFR-classification method or the corresponding rational allowable stress method proposed in this paper may have to be introduced into the classification practice.

• Nuclear Engineering and Technology
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• v.16 no.2
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• pp.97-105
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• 1984

A method and computer code for the uncertainty analysis in the top event unavailability are developed and tested by combining Monte Carlo Method and Moments method with fault tree reduction technique. Using system fault trees and unavailability data selected in WASH-1400, the efficiency of the proposed method is tested and these results are compared with those obtained by Monte Carlo method. It is shown that the results are sufficiently good in accuracy and computation time is considerably reduced compared with those by Monte Carlo method.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.4
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• pp.191-199
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• 2013

It is estimated and analyzed that the design wave height and the confidence interval (hereafter CI) according to the return period using the fourteen-year wave data obtained at Pusan New Port. The functions used in the extreme value analysis are the Gumbel function, the Weibull function, and the Kernel function. The CI of the estimated wave heights was predicted using one of the Monte-Carlo simulation methods, the Bootstrap method. The analysis results of the estimated CI of the design wave height indicate that over 150 years of data is necessary in order to satisfy an approximately ${\pm}$10% CI. Also, estimating the number of practically possible data to be around 25~50, the allowable error was found to be approximately ${\pm}$16~22% for Type I PDF and ${\pm}$18~24% for Type III PDF. Whereas, the Kernel distribution method, a typical non-parametric method, shows that the CI of the method is below 40% in comparison with the CI of the other methods and the estimated design wave height is 1.2~1.6 m lower than that of the other methods.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.605-608
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• 2004

내장형 시스템(embedded system)의 발전에 따라, 더욱 복잡하고 높은 신뢰성을 가지는 내장형 응용프로그램의 개발 필요성이 요구된다. 내장형 소프트웨어의 성능 평가 및 분석 도구는 내장형 소프트웨어 개발 속도와 신뢰성을 높이기 위한 유용한 도구이다. 개발자나 사용자는 성능 평가 결과와 로그 정보를 직관적으로 판단하기 위해 GUI 형태의 결과보고 도구(result report tool)나 뷰어(viewer)를 이용할 수 있다. 그러나 보통의 성능 평가 및 분석 도구가 이용하는 로그 데이터는 텍스트 기반의 저수준 정보이므로, 개발자의 다양한 요구에 맞는 분석 결과보고 도구 나 뷰어를 생성하기 위해서는 로그 정보에 대해 많은 분석 시간과 노력을 기울여야 한다. 본 논문은 내장형 시스템 개발자가 쉽고 편리하게 원하는 GUI 형태의 결과 분석도구를 생성할 수 있도록 하기 위한 프로파일 로그 분석 방법을 제안한다. 제안하는 로그 분석 방법은 저수준의 성능 평가 로그를 분석하여 자료구조화 하는 모듈과 이것을 GUI 형태로 쉽게 변경할 수 있는 API 수준의 함수를 제공한다. 제안하는 로그 분석 방법에 의한 API를 통해 개발자나 사용자는 자신의 취향에 맞는 GUI 형태의 결과 분석 도구를 쉽고 빨르게 생성하여 내장형 소프트웨어 개발의 효율성을 높일 수 있다.

• The Journal of the Korea Contents Association
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• v.18 no.7
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• pp.95-102
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• 2018

The purpose of current research is to develop insight regarding the relationship between trust in leader and followers' goal orientation. In this study relationships among trust in leader, self-efficacy, and goal orientation are explored. Hypotheses about how the trust in leader affect self-efficacy and goal orientation are developed. The sample consists of 389 workers in a firm who are chosen through the judgement sampling method. Findings are reported from the empirical research that partially support the hypothesized relationships among trust in leader, self-efficacy, and goal orientation. Trust in leader have a significant impact on goal orientation, and it is moderated by self-efficacy. The results suggest that leaders need to make an effort for trust building to have positive goal orientations. The findings of this study have theoretical and managerial implications for leadership, trust, and goal orientation research.

• The Transactions of the Korea Information Processing Society
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• v.6 no.2
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• pp.326-334
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• 1999

There are the fault tolerance technology and the fault avoidance technology to analyze and evaluate the performance of computer system. To improve the relibility of software The N-Version Programming (NVP) technology is known to be the most objective and quantitive. However, when discrete probability distribution is used as estimation model, the values of it's component reliability should be same. In this paper, to resolve this problem, we adapted the genetic algorithms to NVP technology and implement the optimized simulate. and the results were analyzed and estimated. Through this study, we could optimize the reliability of each component and estimate the optimum count in the system reliability.