• Journal of Applied Reliability
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• v.16 no.1
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• pp.32-40
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• 2016

Purpose: The purpose of this study is to analyze the effect of sampling points on accuracy of storage reliability estimation for one-shot systems by assuming a weibull distribution as a storage reliability distribution. Also propose method for determining of sampling points for increase the accuracy of reliability estimation. Methods: Weibull distribution was divided into three sections for confirming the possible to estimate the parameters of the weibull distribution only some section's sample. Generate quantal response data for failure data. And performed parameter estimation with quantal response data. Results: If reduce sample point interval of 1 section, increase the accuracy of reliability estimation although sampling only section 1. Even reduce total number of sampling point, reducing sampling time interval of the 1 zone improve the accuracy of reliability estimation. Conclusion: Method to increase the accuracy of reliability estimation is increasing number of sampling and the sampling points. But apply this method to One-shot system is difficult because test cost of one-shot system is expensive. So propose method of accuracy of storage reliability estimation of one-shot system by adjustment of the sampling point. And by dividing the section it could reduce the total sampling point.

• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.113-121
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• 1997

Human reliability attempts to make precise quantitative analyses and predictions of the performance of human-machine(or product) systems. In order to yield more precise human error analysis, precise human error probabilities(HEPs) must be used in the analysis. However, because human behavior is influenced by factors that are called performance shaping factors(PSFs), the effects of PSFs must be considered to obtain precise HEPs, These are called basic HEPs or situation-specific HEPs. This paper presents a theoretical method for obtaining basic HEPs (i.e. , considering PSFs) in quantitative human error analysis. In this method, the weight which characterizes the degree of importance of several PSFs is obtained by the analytic hierarchy process. The quality scores of PSFs in the task situation are obtained by percentile concept. These scores are used in conjunction with the relative Importance weights of PSFs to compute the composite quality percentile score of PSFs in the task situation. Then, a new mapping method of the composite quality percentile score of PSFs into a situation-specific basic HEP is proposed with a numerical example.

• The Journal of Industrial Distribution & Business
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• v.10 no.5
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• pp.77-86
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• 2019

Purpose - The present study examined the reliability of accounting information based on the pay slice (CPS) information of chief executive officers (CEOs) in the service industry. The difference in the size of CPS under the capitalist system can be used as an index to gauge the influence of top management. Research design, data, and methodology - In accordance with the amendment of the Financial Investment Services and Capital Market Act in 2013, the pay information of individual registered executives with annual salary of more than 500 million won has been disclosed. The sample of the current study is 232 companies listed on the Korea Exchange excluding financial services from 2013 to 2015, when the individual pay-slice information for registration officers was published in the business report in accordance with the revision of the Capital Market Act. The financial data required for this study were extracted from the FnGuide and the TS-2000. With the data, we tested the relationship between CPS and accounting information reliability through a linear regression analysis. Results - The first result showed that the relationship between the CPS and human resource in internal accounting control system in the service industry is significantly negative only with the accounting department personnel. This result implied that the CEO can negatively affect the retention of the accounting department in the firm. Second, both the CPS and quality of audit in the service industry are negatively related both to audit fees and to audit time. Nonetheless, the relationship between the number of the auditor and the CPS is insignificant. This result indicated that the CEO can negatively affect audit fees and audit time of external auditors. The results of the present study suggested that CPS information may have a negative impact on the reliability of accounting information. Conclusion - This study is the first study to examine the reliability of CPS and accounting information for the service industry in terms of human resources in internal accounting control system and audit quality. Therefore, the present study is expected to provide some useful information to economic decision-making of various external parties for service firms.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.5
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• pp.49-58
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• 2013

Appropriate random variables and probability density functions based on statistical analysis should be defined to execute reliability analysis. Most studies have focused on only normal distributions or assumed that the variables showing non-normal characteristics follow the normal distributions. In this study, the reliability problem with non-normal probability distribution was dealt with using the convolution method in the case that the integration domains of variables are limited to a finite range. The results were compared with the traditional method (linear transformation of normal distribution) and Monte Carlo simulation method to verify that the application was in good agreement with the characteristics of probability density functions with peak shapes. However it was observed that the reproducibility was slightly reduced down in the tail parts of density function.

• Nuclear Engineering and Technology
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• v.15 no.1
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• pp.11-22
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• 1983

The reliability of the Chemical and Volume Control System has been analyzed in a pressurized water reactor. The boration failure was taken to be the top event for this reliability analysis. A detailed fault tree was constructed and the minimal cut sets were derived. It was computed that the unavailability of the Chemical and Volume Control System due to boration failure was 1.497$\times$10$^{-5}$ during plant operation. It was found that the reliability of boric acid transfer pumps were the most important factors in the availability of the Chemical and Volume Control System. As expected, human errors also introduce the high system unavilability.

• Journal of the military operations research society of Korea
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• v.23 no.1
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• pp.76-87
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• 1997

This paper deals with reliability and MTTF analysis of a non-repairable man-machine system operating under different weather conditions. The system consists of a hardware(machine) and a two-operator standby subsystem such as the air combat maneuvering of fighters with dual seat. The failure times for the subsystems follow the exponential distribution with constant parameter. By considering not only the effect on hardware component but also the weather conditions and human performance factors such as the operator's errors, a Markov model is presented as a method for evaluating the system reliability of time continuous operation tasks. Laplace transforms of the various state probabilities have been derived and then reliability of the system, at any time t, has been computed by inversion process. MTTF has also been computed.

• ETRI Journal
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• v.44 no.1
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• pp.155-167
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• 2022

The Internet of Things (IoT) is a new paradigm that connects physical and virtual objects from various domains such as home automation, industrial processes, human health, and monitoring. IoT sensors receive information from their environment and forward it to their neighboring nodes. However, the large amounts of exchanged data are vulnerable to attacks that reduce the network performance. Most of the previous security methods for IoT have neglected the energy consumption of IoT, thereby affecting the performance and reducing the network lifetime. This paper presents a new multistep routing protocol based on cellular learning automata. The network lifetime is improved by a performance-based adaptive reward and fine parameters. Nodes can vote on the reliability of their neighbors, achieving network reliability and a reasonable level of security. Overall, the proposed method balances the security and reliability with the energy consumption of the network.

• Korean Journal of Human Ecology
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• v.17 no.1
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• pp.35-43
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• 2008

The purpose of this study is to develop evaluation tools for young children's mathematical ability based on the content standards of NCTM and to verify the suitability of the tools. The tools consist of 5 sub-tests with 90 items, including number and operation, algebra, geometry, measurement, data analysis and probability. The tool analysis was examined with 300 three-to five-years-old children and 31 math education professionals. The results of this research are as follows : First, in order of age the passing rate increased. The gap between high and low score group reveals a statistically meaningful difference. Second, the internal consistency reliability coefficient, Cronbach ${\alpha}$, is .96. Test-retest reliability is around .90. The concurrent validity correlation between this tools and Choi Hye-Jin's test(2003) is .85. The analysis of the content validity was proved appropriately by math education professionals.

• Proceedings of the Korean Society of Computer Information Conference
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• 2015.07a
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• pp.53-54
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• 2015

SW 기술이 급변하는 현 시점에서는 SW 관리의 중요성이 인식되어 SW 품질향상을 위한 제도 개선의 일안으로 SW 개발 산출물에 대한 SW 신뢰성 시험이 요구되고 있으나, SW 신뢰성 시험에 투입되는 비용, 시간적 제약 및 휴먼에러 등으로 인해 SW 시험요구조건을 충족하는데 어려움이 있다. 본 논문에서는 문제 해결 도구로써 린6시그마 방법론을 활용하여 SW 신뢰성시험시간을 단축하고 인적오류를 감소할 수 있는 방안을 제안한다.

• Journal of the Korean Society of Systems Engineering
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• v.19 no.1
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• pp.1-13
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• 2023

Transportation of goods by rail in border areas requires considerable time, money, and human resources. Therefore, in this study, a blockchain-based non-stop passing system is proposed to solve this problem. In this study, each transit station and train are designated as one network node, and the corresponding node participates in the blockchain network to record and verify data. In the process, we will design a blockchain network using Docker and design a network interface. Without changing the data and information generated in the existing legacy clearance system, it is possible to configure a blockchain network to ensure the integrity and reliability of the data and to minimize the consumption of time and human resources. The railroad non-stop passing system aims to change the existing legacy system to a blockchain-based non-stop passing system.