• International Journal of Reliability and Applications
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• 제2권1호
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• pp.37-48
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• 2001

This paper presents a new dynamic human reliability analysis method and its application for quantifying the human error probabilities in implementing management action. For comparisons of current HRA methods with the new method, the characteristics of THERP, HCR, and SLIM-MAUD, which are most frequency used method in PSAs, are discussed. The action associated with implementation of the cavity flooding during a station blackout sequence is considered for its application. This method is based on the concepts of the quantified correlation between the performance requirement and performance achievement. The MAAP 3.0B code and Latin Hypercube sampling technique are used to determine the uncertainty of the performance achievement parameter. Meanwhile, the value of the performance requirement parameter is obtained from interviews. Based on these stochastic obtained, human error probabilities are calculated with respect to the various means and variances of the things. It is shown that this method is very flexible in that it can be applied to any kind of the operator actions, including the actions associated with the implementation of accident management strategies.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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• pp.204-207
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• 2005

A reliable and practical finite element modeling technique to predict the lifetime of automotive electronics is important for engineers in reliability. In reliability evaluation on the automotive electronics, most studies rarely used FE model verification process. The material properties and boundary conditions are very important factors in this process to assure the reliability of the automotive electronics. This study aims to develop a better and more accurate FE model in order to predict fatigue life of the automotive electronics using Virtual Qualification lifetime assessment techniques. After conducting the modal analysis by the experiments to grasp a system characteristic, this paper presents material properties and boundary conditions that is obtained by the comparisons of FEA simulation results using DOE technique and the experiment results.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3092-3097
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• 2007

Although noise of a RAC can be reduced effectively by decreasing RPM, condensation problems can occur to reduce reliability of the RAC for low RPM. Thus, this research has been performed to propose a design guideline of the RAC for low-noise RPM with high reliability. The internal and external flows of the RAC have been visualized and analyzed by a PIV technique to solve the condensation problem at an outlet and impeller. Then, the design guideline has been proposed by the analyzed results and confirmed by wind-tunnel and noise tests to reduce the condensation problem. Finally the shapes of the outlet with reduced condensation problem and the impeller with low noise have been obtained in this study.

• 한국농공학회지
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• 제39권2호
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• pp.95-102
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• 1997

The technique of the calculation for probabilistic functions used in the reliability analysis of agricultural structures is proposed in this paper for adapting the standardization method using a numerical intergration. The proposed standardization method deals with the structures whose deviations of material properties and loads are large such that the deviation range from 20% to 70%. The results computed by the proposed method are compared with those obtained by the Monte Carlo Simulation. Deterministic values such as deflection, stress, obtained by conventional structural analysis can be directly changed to probabilistic distributions by the proposed method.

• 전기학회논문지P
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• 제66권1호
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• pp.33-37
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• 2017

This paper describes the modeling of the failure rate estimation technique for applying the asset management technique to electric power facilities. There are many modeling techniques to estimate the failure rate. In this paper, the characteristics of the normal distribution, exponential distribution, weibull distribution, and piecewise linear functions are discussed. When evaluating reliability, the evaluation may be less meaningful if the sample data is insufficient. Therefore, Weibull distribution and piecewise linear function are adopted as the most suitable functions for estimating the failure rate of power facilities and the resulting failure rate function is derived.

• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2000년도 춘계학술대회 발표논문집
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• pp.123-129
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• 2000

SPC is the quality improvement technique of gathering since Motorola of U.S.A. have used SPC technique as a statistical process control method for promoting 6-sigma quality improvement strategy in 1988. In Korea, small and medium-sized enterprises are needed building of a system for statistical production control . In the present study, the methods of building SPC system with a moderate cost using a graphic programs of easy-to-use and high flexibility for small and medium-sized enterprises were inquired. The SPC system which enables statistic marking (maximum, minimum, mean, standard deviation, process capability index) and graph marking (X-Y coordinates and histogram) using LabVIEW 5.0, the graphic program by National Instrument Co., Ltd. was implemented in this study.

• 전기학회논문지
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• 제60권7호
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• pp.1314-1323
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• 2011

The maintenance of generating units is implicitly related with power system reliability and has a tremendous bearing on the operation of the power system. A technique using a fuzzy search method which is based on fuzzy multi-criteria function has been proposed for GMS (generator maintenance scheduling) in order to consider multi-objective function. In this study, a new technique using combined fuzzy set theory and genetic algorithm(GA) is proposed for generator maintenance scheduling. The genetic algorithm(GA) is expected to make up for that fuzzy search method might search the local solution. The effectiveness of the proposed approach is demonstrated by the simulation results on a practical size test systems.

• 반도체디스플레이기술학회지
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• 제20권4호
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• pp.114-118
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• 2021

In this research, the dimensional error of the measured specimen according to the measurement method was analyzed for the length, angle, radius of curvature and diameter using a projector which is used in industry. One-way analysis was performed on each data tested 30 times using a statistical technique. Through the experiment, it was found that an error occurred in each data when measuring the length and radius of curvature according to the measurement method, and the null hypothesis that no error occurred when measuring the angle and length was established. Based on this experimental data, the automatic measurement when measuring the projector causes less measurement error, so automatic measurement is recommended when measuring a small product. Also, an optimal measuring method is suggested for securing reliability on formulations of measurement automation.

• 드라이브 ㆍ 컨트롤
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• 제9권4호
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• pp.88-96
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• 2012

• International Journal of Reliability and Applications
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• 제12권1호
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• pp.15-39
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• 2011

This paper deals with the reliability analysis of a complex system with three possibilities at the time of repair. The considered system consists of two subsystems A and Bin series configuration (1-out-of-2: F). Subsystem A has n units which are connected in series whereas subsystem B consists of n units in parallel configuration. The configuration of subsystem A is of 1-out-of-n: F whereas subsystem B is of k-out-of-n: D and k+1-out-of-n: F nature. System has three states: Good, degraded and failed. Supplementary variable technique has been used for mathematical formulation of the model. Laplace transform is being utilized to solve the mathematical equation. Reliability, Availability, M.T.T.F., Busy Period and Cost effectiveness of the system have been computed. The repairs from state $S_7$ to $S_0$, $S_8$ to $S_0$, $S_9$ to $S_0$ and $S_{11}$ to $S_0$ have two types namely exponential and general. Joint probability distribution of repair rate from $S_7$ to $S_0$, $S_8$ to $S_0$, $S_9$ to $S_0$ and $S_{11}$ to $S_0$ is computed by Gumbel-Hougaard family of copula. Some particular cases of the system have also been derived to see the practical importance of the model.