• Title/Summary/Keyword: Reliability Study

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A Study on Reliability (신뢰성에 관한 고찰)

  • 이근희
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.2 no.2
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    • pp.1-4
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    • 1979
  • In order to cope with the violent environment of surrounding enterprises, development of new products, advance to other industry field, unification or abolition of factories and rationlization of labor are needed. But production process being made quality and using process after shipment are the things that we have to think about, first of all and to practice always. Insurance problem of reliability, that is, the positive quality maintenance that has being presented many debate issues recently, will be studied. The accident of nuclear power-plant in America, in connection with reliability maintenance and human engineering, will be analyzed. But as its accident details is not announced, in this study, it is a sort of method of methodology to be studied this paper rather than studying the fact of the accident. Therefore this study will be done as follows, For reliability study. 1. Investigation of problems. 2. Quality maintenance activity and reliability maintenance activity 3. Reliability acquisition in production process, 4. Reliability maintenance after shipment. 5. Conclusion. In addition to stating above, it is sure that liberalization of trade, interchange between nations and strengthening of international competition ability, etc. need high quality. But possibility that quality maintenance or reliability aquisition needs understanding and cooperation of consumer, will be stated.

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A study on Reliability Analysis for Plane Frame Structure (평면뼈대구조의 신뢰성해석에 관한연구)

  • 이중빈;신형우
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1989.10a
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    • pp.34-39
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    • 1989
  • Recent trends in design standards development have encouraged the use of probabilistic limit sate design concepts. Reliability analysis adopted in those advanced countries have the potentials that they afford for symplifying the design Process arid placing it on a consistent reliability based for various construction materials. This study is proposed in the reliability analysis of plane frame structures using second-order moment method(Level-II they). Lind-Hasofer's minimum distance method is use in the derivation of an mathematical algorithm as well as an determination of Correlation cofficients, reliability index and total reliability index depending on the multiple failure modes. In addition. This study is employed as a practical tool for the approximate reliability analysis. Results of the numerincal analysis showed that the difference between the reliability index of the failure probability of the multiple failure modes and the total reliability index of the failure probability with the simultaneous failure modes deviated nearly 3∼10% depending on tile performance functions.

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The software quality measurement based on software reliability model (소프트웨어 신뢰성 모델링 기반 소프트웨어 품질 측정)

  • Jung, Hye-Jung
    • Journal of the Korea Convergence Society
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    • v.10 no.4
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    • pp.45-50
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    • 2019
  • This study proposes a method to measure software reliability according to software reliability measurement model to measure software reliability. The model presented in this study uses the distribution of Non - Homogeneous Poisson Process and presents a measure of the software reliability of the presented model. As a method to select a suitable software reliability growth model according to the presented model, we have studied a method of proposing an appropriate software reliability function by calculating the mean square error according to the estimated value of the reliability function according to the software failure data. In this study, we propose a reliability function to measure the software quality and suggest a method to select the software reliability function from the viewpoint of minimizing the error of the estimation value by applying the failure data.

A Study for Reliability Target Setting Considering Warranty Cost and Reliability Analysis Result of Process Controller in Nuclear Power Plant (원자력 발전소용 공정 제어기의 보증 비용을 고려한 신뢰도 목표치 설정과 신뢰도 분석 결과에 대한 연구)

  • Kim, Gun Myung
    • Journal of Applied Reliability
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    • v.15 no.3
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    • pp.145-148
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    • 2015
  • The products to meet the requirement of are installed in nuclear power plant and the reliability target should be provided in the requirement. However, it is not easy to set a reliability target using quantitative analysis. The objective of this paper is to propose a method of reliability target setting considered warranty cost for process controller and then compare a reliability target with reliability analysis result.

Reliability study of CFRP externally bonded concrete beams designed by FIB bulletin 14 considering corrosion effects

  • Dehghani, Hamzeh
    • Advances in concrete construction
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    • v.13 no.2
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    • pp.191-198
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    • 2022
  • FIB is introduced as the sole guideline for the design purpose that results in a practical relationship for the torsional capacity of concrete beams strengthened with carbon fiber-reinforced polymer (CFRP). This study applies first-order reliability method to assess the reliability evaluation of the torsional capacity of CFRP-strengthened beams on the basis of FIB guidelines. In terms of steel reinforcement losses, this study applies a corrosion model to investigate the ceaseless deterioration of the existing structure. Hence, the average of reliability indices varies between 2.68 and 2.80, indicating the reliability viewpoint of the design methodologies. The average values are somehow low compared to the target values of reliability (3.0 or 3.5) applied in the calibration stage of the FIB guideline. In this way, the partial safety factors may change in the forthcoming guideline revisions. For this aim, the reliability of strengthening ratio was applied to assess the variation in the average value of the reliability index with different partial safety factors. The performance of parametric study for the factor proved that minimum values of 1.60 and 2.32 are required for target values of reliability (3.0 and 3.5), respectively.

Development of the Reliability Index for Improving the Reliability of the Manufacturing Equipment (제조업 장비의 신뢰성 향상을 위한 신뢰성지수 개발)

  • Yu, Sangwoo;Park, Jungwon;Kim, Min;Hong, Jungpyo;Oh, Geuntae;Na, Yoonkyoon
    • Journal of Applied Reliability
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    • v.16 no.3
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    • pp.245-253
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    • 2016
  • Purpose: The purpose of this study is to measure the reliability of complex equipment. Reliability of product is one of the most important factor to achieve competitiveness in the market. While there were many researches for assessing the reliability on components and modules, research on quantitative assessment tool for equipment with many component was little because of equipment's complexity. Methods: In this article, we developed index to assess reliability management system by using IEC 60300 and Reliability Management Tool-kit. With MIR and BARS, we developed reliability index clauses relevant to reliability activities and found weight factor for each clause by survey on experts. Results: The results of this study were as follows; reliability index that can assess both management side and technology side of the company was developed. Conclusion: Using this index, we assessed the reliability of a manufacturing equipment and found out the current reliability level of the manufacturing equipment, and derived improvement points.

A Study on the Validity and Reliability of Performance Assessment in Home Economics (가정과 수행평가의 타당성과 신뢰성 연구 - 경남 농촌지역의 소인수 학급을 대상으로 -)

  • 윤성희;유태명
    • Journal of the Korean Home Economics Association
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    • v.39 no.10
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    • pp.169-186
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    • 2001
  • The purpose of the study was to verify validity and reliability of performance assessment in home economics by applying performance assessment tools developed by Korean Curriculum Assessment Institute and by the researcher to a class of 17 high school female students in a rural area. For the purpose of this study, the research question was formulated and addressed:“How are the validity and reliability of performance assessment in home economics\ulcorner” The results of the study were as follows. 1. The results of testing validity a. Thirteen high school home economics teachers, whose average teaching years is ten years verified high validity in the contents of performance assessment. b. In the validity of the items that is verified being based on the scores of high school entrance examination of 2000 school year, the essay type showed its characteristics as performance assessment. c. The generalizability among assessment methods was not high. 2. The results of testing reliability Both Cronbach's $\alpha$, inter-item reliability of the assessment tools used in the research, and reliability among the raters were high. But reliability among the tasks was relatively low. This study proposed that the diverse performance methods, the increasing number of assessment, the explicit assessment criterion, and scoring criterion are needed to satisfying validity and reliability of performance assessment.

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Reliability and validity of free software for the analysis of locomotor activity in mice

  • Hong, Yoo Rha;Moon, Eunsoo
    • Journal of Yeungnam Medical Science
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    • v.35 no.1
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    • pp.63-69
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    • 2018
  • Background: Kinovea software that tracking semi-automatically the motion in video screen has been used to study motion-related tasks in several studies. However, the validation of this software in open field test to assess locomotor activity have not been studied yet. Therefore, this study aimed to examine the reliability and validity of this software in analyzing locomotor activities. Methods: Thirty male Institute Cancer Research mice were subjected in this study. The results examined by this software and the classical method were compared. Test-retest reliability and inter-rater reliability were analyzed with Pearson's correlation coefficient and intraclass correlation coefficient (ICC). The validity of this software was analyzed with Pearson's correlation coefficient. Results: This software showed good test-retest reliability (ICC=0.997, 95% confidence interval [CI]=0.975-0.994, p<0.001). This software also showed good inter-rater reliability (ICC=0.987, 95% CI=0.973-0.994, p<0.001). Furthermore, in three analyses for the validity of this software, there were significant correlations between two methods (Pearson's correlation coefficient=0.928-0.972, p<0.001). In addition, this software showed good reliability and validity in the analysis locomotor activity according to time interval. Conclusion: This study showed that this software in analyzing drug-induced locomotor activity has good reliability and validity. This software can be effectively used in animal study using the analysis of locomotor activity.

The Study of International Reliability Standards Specifications (신뢰성 국제 표준규격에 대한 연구)

  • Nam, Kyung H.
    • Journal of Applied Reliability
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    • v.15 no.2
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    • pp.101-107
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    • 2015
  • In this paper, we review the domestic reliability standards and its global counterparts IEC/TC 56 international reliability standards. Recently private transfers of reliability certification control tower has established in Korea. Some check points to consider regarding the control tower transfer process to the non-government organization are suggested. Also the IEC/TC 56 and its relevant reliability standards are introduced. Understanding of the IEC/TC56 system will be helpful for the time of non-government organization control tower transfer in the reliability certificate specification

A Study on Probabilistic Reliability Evaluation Considering Transmission System :TRELSS and TranRel (송전계통을 고려한 확률론적 신뢰도 평가에 관한 연구 : TRELSS and TranRel)

  • 최재석;강성록;트란트롱틴;전동훈;문승필;추진부
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.53 no.1
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    • pp.43-55
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    • 2004
  • This paper presents a study on evaluating the reliability indices considering a transmission system. Because successful operation of electric power under the deregulated electricity market depends on transmission system reliability management, quantity evaluation of transmission system reliability is very important. This paper introduces features and operation modes of the Transmission Reliability Evaluation for Large-Scale Systems(TRELSS) Version 6.0, a commercial program made in EPRI, and TranRel-I V3.2, a educational program made in GSNU(GyeongSang National University) for assessing reliability indices of composite power system. The packages access not only bulk but also bus indices for reliability evaluation of composite powers system. The practicality, effectiveness and future works of this methodology are illustrated by demonstrations of two case studies of modified IEEE 25 buses reliability test system using TRELSS and TranRel-I and a brief case study for the KEPCO size system using TranRel-II made in GSNU.