• Title/Summary/Keyword: failure analysis

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A Comparison of the Discrimination of Business Failure Prediction Models (부실기업예측모형의 판별력 비교)

  • 최태성;김형기;김성호
    • Journal of the Korean Operations Research and Management Science Society
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    • v.27 no.2
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    • pp.1-13
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    • 2002
  • In this paper, we compares the business failure prediction accuracy among Linear Programming Discriminant Analysis(LPDA) model, Multivariate Discriminant Analysis (MDA) model and logit analysis model. The Data for 417 companies analyzed were gathered from KIS-FAS Published by Korea Information Service in 1999. The result of comparison for four time horizons shows that LPDA Is advantageous in prediction accuracy over the other two models when over all tilt ratio and business failure accuracy are considered simultaneously.

Life Cycle Cost & Reliability Analysis of Quaywall Design Parameters (안벽 설계변수의 신뢰성 해석과 생애주기비용 분석)

  • Kim, Hong-Yeon;Yoon, Gil-Lim;Yoon, Yeo-Won
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.508-518
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    • 2008
  • Reliability and sensitivity analysis of the design parameters for a section of caisson type quaywall which is the most applicable in Korea were performed. It was tried to estimate probabilities of failure for the system of the multiple failure modes and to analyze LCC in the quaywall structure. The reliability analysis was performed by FORM. Also, sensitivity indices were estimated using the reliability indices, which may be used inferring effects of each design parameter on the reliability indices. As a result, the coefficient of friction between caisson and rubble, the moment by self weight and the moment of resistance mostly affected on the reliability indices in the sliding, overturning and foundation failure, respectively. System reliability theorem was applied in order to estimate the probabilities of failure for the system of the multiple failure modes. As the results of estimation of the probabilities of failure for the system, all cases were more conservative than those for the elements, according to both failure mode and load combination applied to series system. It entirely exceeded the target reliability index, but it was consistent with the theorem. According to the optimum LCC with the width of the caisson, the probability of failure exceeded the target probability of failure at then time. Therefore, it was judged to be insufficient to the practical application.

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A Study on the Development of FRACAS-based Failure Analysis Workflow for Military weapon system (FRACAS에 기반한 군 무기체계의 고장분석 워크플로우 구축에 대한 연구)

  • Lee, Min-Young;Kim, Wan-Gul;Kim, Kyung-Soo
    • Journal of Applied Reliability
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    • v.10 no.2
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    • pp.93-105
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    • 2010
  • The following thesis provides an explanation for the definition of the MIL-HDBK-2155 : Failure Reporting, Analysis and Corrective Action System (FRACAS), which systemizes the collection and analysis of failure data and the feedback process of the results. It also presents a plan based on MIL-HDBK-2155 for the collection and analysis of operating specifications on weapon systems. The collection and analysis of failure data and the feedback process utilizing FRACAS contributes to identifying improvement requirements during equipment operation as well as finding and eliminating the root cause of the failures. The objective of applying FRACAS to weapon systems is to receive source data feedback for reliability enhancements and performance improvements during operation. This is done by recognizing weaknesses in the design or operation by identifying the type of failures that might occur, and by performing Failure Modes, Effects and Criticality Analysis(FMECA) and Failure Tree Analysis(FTA).

A Study on Reliability Data Analysis for Components of Machining Center (공작기계 부품의 신뢰성 데이터 해석에 관한 연구)

  • 이수훈;김종수;송준엽;이승우;박화영
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.88-91
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    • 2001
  • The reliability data analysis for components of CNC machining center is studied in this paper. The failure data of mechanical part is analyzed by Exponetial, Weibull, and Log-normal distributions. And then, the optimum failure distribution model is selected by goodness of fit test. The reliability data analysis program is developed using ASP language. The failure rate, MTBF, life, and failure mode of mechanical parts are estimated and searched by this program. The failure data and analysis results are stored in the database.

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A Study on the Forecast of Construction Business Failure according to Financial Ratio (재무비율을 이용한 건설기업의 도산 예측)

  • Heo, Woo-Young;Suk, Chang-Mok;Kim, Wha-Jung
    • Journal of the Korea Institute of Building Construction
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    • v.4 no.2
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    • pp.137-142
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    • 2004
  • There was the time of IMF(1998) that management condition of construction business had been the worst. After that time, structural regulation was completed and financial structure was returned to normalcy(2001). At that time, the aim of this paper is that fifteen construction business are researched for process of management condition and capital structure after they is selected as samples for three years, also failure of two-groups is predicted as statistics analysis and multiple discriminant analysis for them. In this paper, It is researched financial statement of business by the forecast experiment of failure and analyzed statistically possibility of failure and success for financial ratio. For them, the fifteen companies of failure and the fifteen companies what were not the failure, for listed company, and the fourteen variables are selected and they are analyzed statistically according to Logit Analysis.

Reliability Analysis of Power System with Dependent Failure (종속고장을 고려한 전력시스템의 신뢰도 평가)

  • Son, Hyun-Il;Kwon, Ki-Ryang;Kim, Jin-O
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.9
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    • pp.62-68
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    • 2011
  • Power system needs to sustain high reliability due to its complexity and security. The reliability prediction method is usually based on independent failure. However, in practice, the Common Cause Failures(CCF) and Cascading failure occur to the facilities in power system as well as independent failures in many cases. The CCF and Cascading failure turn out the system collapse seriously in a wide range. Therefore to improve the reliability of the power system practically, it is required that the analysis is conducted by using the CCF and Cascading failure. This paper describes the CCF and Cascading failure modeling combined with independent failure. The incorporated model of independent failure, CCF and cascading failure is proposed and analyzed, and it is applied to the distribution power system in order to examine this method.

The Study for Software Future Forecasting Failure Time Using Curve Regression Analysis (곡선 회귀모형을 이용한 소프트웨어 미래 고장 시간 예측에 관한 연구)

  • Kim, Hee-Cheul;Shin, Hyun-Cheul
    • Convergence Security Journal
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    • v.12 no.3
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    • pp.115-121
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    • 2012
  • Software failure time presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing. For data analysis of software reliability model, data scale tools of trend analysis are developed. The methods of trend analysis are arithmetic mean test and Laplace trend test. Trend analysis only offers information of outline content. In this paper, we discuss forecasting failure time case of failure time censoring. In this study, we predict the future failure time by using the curve regression analysis where the s-curve, growth, and Logistic model is used. The proposed prediction method analysis used failure time for the prediction of this model. Model selection using the coefficient of determination and the mean square error were presented for effective comparison.

The System Reliability Analysis of Web Frame by Plastic Strength Analysis (소성 강도 해석에 의한 Web Frame의 시스템 신뢰성 해석)

  • Y.S. Yang;S.J. Yim
    • Journal of the Society of Naval Architects of Korea
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    • v.28 no.2
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    • pp.251-267
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    • 1991
  • Plastic strength analysis using plastic failure mode as a limit state is adopted instead of a conventional elastic structural analysis to predict the ultimate strength of Web frame idealized by a plane frame. Linear programming arid Compact procedure are developed for determining the collapse load factor. It is found that the final results are good agreement with the results of Elasto-plastic analysis. Besides, the redundant structures like Web frame is known to have multiple failure modes. Web frame may collapse under any of the possible failure modes. Thus, the identification of these possible failure modes is necessary and very important in the reliability analysis of Web frame. In order to deal with multiple failure modes, automatic generation method of all failure modes and basic failure modes is used for selecting the dominant failure modes. The probability of failure pastic collapse of Web frame is calculated using these dominant failure modes. The safety of Web frame is asscssed and compared by performing the deterministic and probabilistic analysis.

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Experimental and analytical investigation on seismic behavior of RC framed structure by pushover method

  • Sharma, Akanshu;Reddy, G.R.;Eligehausen, R.;Vaze, K.K.
    • Structural Engineering and Mechanics
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    • v.39 no.1
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    • pp.125-145
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    • 2011
  • Pushover analysis has gained significant popularity as an analytical tool for realistic determination of the inelastic behaviour of RC structures. Though significant work has been done to evaluate the demands realistically, the evaluation of capacity and realistic failure modes has taken a back seat. In order to throw light on the inelastic behaviour and capacity evaluation for the RC framed structures, a 3D Reinforced concrete frame structure was tested under monotonically increasing lateral pushover loads, in a parabolic pattern, till failure. The structure consisted of three storeys and had 2 bays along the two orthogonal directions. The structure was gradually pushed in small increments of load and the corresponding displacements were monitored continuously, leading to a pushover curve for the structure as a result of the test along with other relevant information such as strains on reinforcement bars at critical locations, failure modes etc. The major failure modes were observed as flexural failure of beams and columns, torsional failure of transverse beams and joint shear failure. The analysis of the structure was by considering all these failure modes. In order to have a comparison, the analysis was performed as three different cases. In one case, only the flexural hinges were modelled for critical locations in beams and columns; in second the torsional hinges for transverse beams were included in the analysis and in the third case, joint shear hinges were also included in the analysis. It is shown that modelling and capturing all the failure modes is practically possible and such an analysis can provide the realistic insight into the behaviour of the structure.

Root Cause Analysis on Delamination Failure between Coating Film and Paper (코팅지 박리파손에 대한 근본원인분석)

  • Lee, D.B.
    • Journal of Power System Engineering
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    • v.9 no.1
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    • pp.57-63
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    • 2005
  • In the calendar and the advertising catalog, the surface is usually coated by coating polypropylene film. The delamination failure of coating film depends on surface roughness and quality of the substrate paper. In this paper, the mechanisms of delamination failure between the coating film and the paper is investigated by using the root cause analysis as one of techniques of reliability evaluation. The papers used in failure analysis are three kind products made by two domestic and one foreign companies. It found that the main causes of delamination failure between the coating film and the paper were the creation of microvoids caused by shape of filler and their growth caused by contraction of paper.

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