• 제목/요약/키워드: Failure Prediction

검색결과 1,212건 처리시간 0.031초

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

  • 최태성;김형기;김성호
    • 한국경영과학회지
    • /
    • 제27권2호
    • /
    • pp.1-13
    • /
    • 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.

Development and application of a floor failure depth prediction system based on the WEKA platform

  • Lu, Yao;Bai, Liyang;Chen, Juntao;Tong, Weixin;Jiang, Zhe
    • Geomechanics and Engineering
    • /
    • 제23권1호
    • /
    • pp.51-59
    • /
    • 2020
  • In this paper, the WEKA platform was used to mine and analyze measured data of floor failure depth and a prediction system of floor failure depth was developed with Java. Based on the standardization and discretization of 35-set measured data of floor failure depth in China, the grey correlation degree analysis on five factors affecting the floor failure depth was carried out. The correlation order from big to small is: mining depth, working face length, floor failure resistance, mining thickness, dip angle of coal seams. Naive Bayes model, neural network model and decision tree model were used for learning and training, and the accuracy of the confusion matrix, detailed accuracy and node error rate were analyzed. Finally, artificial neural network was concluded to be the optimal model. Based on Java language, a prediction system of floor failure depth was developed. With the easy operation in the system, the prediction from measured data and error analyses were performed for nine sets of data. The results show that the WEKA prediction formula has the smallest relative error and the best prediction effect. Besides, the applicability of WEKA prediction formula was analyzed. The results show that WEKA prediction has a better applicability under the coal seam mining depth of 110 m~550 m, dip angle of coal seams of 0°~15° and working face length of 30 m~135 m.

필드데이터 기반의 유도탄 신뢰도 예측 (Reliability Prediction Based on Field Failure Data of Guided Missile)

  • 서양우;이계신;이연호;김제용
    • 한국신뢰성학회지:신뢰성응용연구
    • /
    • 제18권3호
    • /
    • pp.250-259
    • /
    • 2018
  • Purpose: Previously, missile reliability prediction is based on theoretical failure prediction model. It has shown that the predicted reliability is inadequate to real field data. Although an MTTF based reliability prediction method using real field data has recently been studied to overcome this issue. In this paper, we present a more realistic method, considering MTBF concept, to predict missile reliability. Methods: In this paper we proposed a modified survival model. This model is considering MTBF as its core concept, and failed missiles in the model are to be repaired and redeployed. We compared the modified model (MTBF) and the previous model (MTTF) in terms of fitness against the real failure data. Results: The reliability prediction result of MTBF based model is closer to fields failure data set than that of MTTF based model. Conclusion: The proposed MTBF concept is more fitted to real failure data of missile than MTTF concept. The methodology of this study can be applied to analyze field failure data of other similar missiles.

항공기 동적 부분품에 대한 신뢰성 평가 (A Study on Reliability Assessment of Aircraft Structural Parts)

  • 김은정;원준호;최주호;김태곤
    • 한국항공운항학회지
    • /
    • 제18권4호
    • /
    • pp.38-43
    • /
    • 2010
  • A continuing challenge in the aviation industry is how to safely keep aircraft in service longer with limited maintenance budgets. Therefore, all the advanced countries in aircraft technologies put great efforts in prediction of failure rate in parts and system, but in the domestic aircraft industry is lack of theoretical and experimental research. Prediction of failure rate provides a rational basis for design decisions such as the choice of part quality levels and derating factors to be applied. For these reasons, analytic prediction of failure rate is essential process in developing aircraft structure. In this paper, a procedure for prediction of failure rate for aircraft structural parts is presented. Cargo door kinematic parts are taken to illustrate the process, in which the failure rate for Hook part is computed by using Monte Carlo Simulation along with Response Surface Model, and system failure rate is obtained afterwards.

공작기계 핵심 Units의 신뢰성 예측 및 Design Review (Reliability Prediction & Design Review for Core Units of Machine Tools)

  • 이승우;송준엽;이현용;박화영
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2003년도 춘계학술대회 논문집
    • /
    • pp.133-136
    • /
    • 2003
  • In these days, the reliability analysis and prediction are applied for many industrial products and many products require guaranteeing the quality and efficiency of their products. In this study reliability prediction for core units of machine tools has been performed in order to improve and analyze its reliability. ATC(Automatic Tool Changer) and interface Card of PC-NC that are core component of the machine tools were chosen as the target of the reliability prediction. A reliability analysis tool was used to obtain the reliability data(failure rate database) for reliability prediction. It is expected that the results of reliability prediction be applied to improve and evaluate its reliability. Failure rate, MTBF (Mean Time Between Failure) and reliability for core units of machine tools were evaluated and analyzed in this study.

  • PDF

인장파단시간 및 응력측정에 의한 SAPH45의 수명예측 (Prediction of life of SAPH45 steel with measured fracture time and strength)

  • 박종민
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 1998년도 춘계학술대회 논문집
    • /
    • pp.269-273
    • /
    • 1998
  • The failure of material structures or mechanical system is considered as a direct or indirect result of fatigue. In the design of mechanical structure for estimating of reliability, the prediction of failure life is the most important failure mode to be considered. However, because of a complicated behavior of fatigue in mechanical structure, the analysis of fatigue is in need of much researches on life prediction. This document presents a prediction of fatigue life of the SAPH45 steel, which is extensively for vehicle frame. The method using lethargy coefficient and stress distribution factor at pediction of fatigue life based on the consideration of the failure characteristics from the tensile test should be provided in this study.

  • PDF

PRISM 신뢰성 예측규격서를 이용한 전자부품(PCB) 신뢰도 예측 (Reliability prediction of electronic components on PCB using PRISM specification)

  • 이승우;이화기
    • 대한안전경영과학회지
    • /
    • 제10권3호
    • /
    • pp.81-87
    • /
    • 2008
  • The reliability prediction and evaluation for general electronic components are required to guarantee in quality and in efficiency. Although many methodologies for predicting the reliability of electronic components have been developed, their reliability might be subjective according to a particular set of circumstances, and therefore it is not easy to quantify their reliability. In this study reliability prediction of electronic components, that is the interface card, which is used in the CNC(Computerized Numerical Controller) of machine tools, was carried out using PRISM reliability prediction specification. Reliability performances such as MTBF(Mean Time Between Failure), failure rate and reliability were obtained, and the variation of failure rate for electronic components according to temperature change was predicted. The results obtained from this study are useful information to consider a counter plan for weak components before they are used.

수산기업의 부실화 요인 및 예측에 관한 연구 (A Study on the Distress Prediction in the Fishery Industry)

  • 이윤원;장창익;홍재범
    • 한국수산경영학회:학술대회논문집
    • /
    • 한국수산경영학회 2007년도 추계학술발표회 및 심포지엄
    • /
    • pp.167-184
    • /
    • 2007
  • The objectives of this paper are to identify the causes of the corporate distress and to develop a distress prediction model with the financial information in fishery industry. In this study, the corporate distress is defined as economic failure and technical insolvency. Economic failure occurs by reduction, shut-down, or change of the business and technical insolvency results from failure to pay the financial debt of companies. The 33 distressed firms from 1991 to 2003 were composed by 14 economic failure companies, 15 technical insolvency companies. 4 companies applied to the both cases. The analysis of distress prediction of fishery companies were accomplished according to the distress definition. The analysis was carried out as two steps. The first step was the univariate analysis, which was used for checking the prediction power of individual financial variable. The t-test is used to identify the differences in financial variables between the distressed group and the non-distressed group. The second step was to develop distress prediction model with logistic regression. The variables showed the significant difference in univariate analysis were selected as the prediction variables. The financial ratios, used in the logistic regression model, were selected by backward elimination method. To test stability of the distress prediction model, the whole sample was divided as three sub-samples, period 1(1990$\sim$1993), period 2(1994$\sim$1997), period 3(1998$\sim$2002). The final model built from whole sample appled each three sub-samples. The results of the logistic analysis were as follows. the growth, profitability, stability ratios showed the significant effect on the distress. the some different result was found in the sub-sample (economic failure and technical insolvency). The growth and the profitability were important to predict the economic failure. The profitability and the activity were important to predict technical insolvency. It means that profitability is the really important factor to the fishery companies.

  • PDF

수산기업의 부실화 요인과 그 예측에 관한 연구 (A Study on the Distress Prediction in the Fishery Industry)

  • 장창익;이윤원;홍재범
    • 수산경영론집
    • /
    • 제39권2호
    • /
    • pp.61-79
    • /
    • 2008
  • The objectives of this paper are to identify the causes of the corporate distress and to develop a distress prediction model with the financial information in fishery industry. In this study, the corporate distress is defined as economic failure and technical insolvency. Economic failure occurs by reduction, shut - down, or change of the business and technical insolvency results from failure to pay the financial debt of companies. The 33 distressed firms from 1991 to 2003 were composed by 14 economic failure companies, 15 technical insolvency companies. 4 companies applied to the both cases. The analysis of distress prediction of fishery companies were accomplished according to the distress definition. The analysis was carried out as two steps. The first step was the univariate analysis, which was used for checking the prediction power of individual financial variable. The t - test is used to identify the differences in financial variables between the distressed group and the non - distressed group. The second step was to develop distress prediction model with logistic regression. The variables showed the significant difference in univariate analysis were selected as the prediction variables. The financial ratios, used in the logistic regression model, were selected by backward elimination method. To test stability of the distress prediction model, the whole sample was divided as three sub-samples, period 1(1990 - 1993), period 2(1994 - 1997), period 3(1998 - 2002). The final model built from whole sample appled each three sub - samples. The results of the logistic analysis were as follows. the growth, profitability, stability ratios showed the significant effect on the distress. the some different result was found in the sub - sample (economic failure and technical insolvency). The growth and the profitability were important to predict the economic failure. The profitability and the activity were important to predict technical insolvency. It means that profitability is the really important factor to the fishery companies.

  • PDF