• Journal of the Korea Safety Management & Science
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• v.6 no.1
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• pp.61-70
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• 2004

In this paper, a group replacement policy based on a failure count is analysed. For a group of identical repairable units, a maintenance policy is performed with two phase considerations: a repair interval phase and a waiting interval phase. Each unit undergoes minimal repair at failure during the repair interval. Beyond the interval, no repair is made until a number of failures. The expected cost rate expressions under the policy is derived. A method to obtain the optimal values of decision variables are explored. Numerical examples are given to demonstrate the results.

• International Journal of Reliability and Applications
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• v.3 no.1
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• pp.51-60
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• 2002

This paper presents the methodology for obtaining point and interval estimating of the parameters of a new two-parameter distribution with multiple-censored and singly censored data (Type-I censoring or Type-II censoring) as well as complete data, using the maximum likelihood method. The basis is the likelihood expression for multiple-censored data. Furthermore, this model can be extended to a three-parameter distribution that is added a scale parameter. Then, the parameter estimation can be obtained by the graphical estimation on probability plot.

• Proceedings of the KIEE Conference
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• 2005.11c
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• pp.131-135
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• 2005

Stabilization of electric power is the most important thing is such place as computing center having business critical equipment. However, ability to cope with electrical quality shift and power failure is very weak from UPS output side to load in those electricity system, though UPS is generally used for power stabilization. this problem can be solved by duplication of power source using newly configured UPS and small sized transfer switch even in case of UPS failure.

• Journal of Applied Reliability
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• v.18 no.3
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• pp.220-228
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• 2018

Purpose: The purpose of this study is to investigate the tail behavior of the life distribution which exhibits an increasing failure rate or other positive aging effects after a certain time point. Methods: We characterize the tail behavior of the life distribution with regard to certain reliability measures such as failure rate, mean residual life and reliability function and derive several stochastic properties regarding such life distributions. Also, utilizing an L-statistic and its asymptotic normality, we propose new nonparametric testing procedures which verify if the life distribution has an increasing tail failure rate. Results: We propose the IFR-Tail (Increasing Failure Rate in Tail), DMRL-Tail (Decreasing Mean Residual Life in Tail) and NBU-Tail (New Better than Used in Tail) classes, all of which represent the tail behavior of the life distribution. And we discuss some stochastic properties of these proposed classes. Also, we develop a new nonparametric test procedure for detecting the IFR-Tail class and discuss its relative efficiency to explore the power of the test. Conclusion: The results of our research could be utilized in the study of wide range of applications including the maintenance and warranty policy of the second-hand system.

• Journal of Distribution Science
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• v.18 no.2
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• pp.79-89
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• 2020

Purpose: This research aimed at exploring the antecedents of feeling ashamed and anger when customers perceive the rightness of object of criticism induced from in-group failure triggered due to my mistake or others' mistake, and identifying the effects of shame and anger on customers' consumption type. Research design, data and methodology: This research used 2 (failure caused by my mistake versus failure caused by others' mistake) between- subjects design, and collected 353 data through on-line survey, and structural equation model of Amos 21.0 was used to verify the hypotheses developed by reviewing the past literature. Results: First, feeling anger motivates customers to choose compensatory consumption behaviors whereas shame leads people to choose adaptive consumption behaviors. Second, customer's feeling of shame and anger is depending on the perceived rightness of the criticism induced from the failure caused by my mistake or others' mistake. Conclusions: Marketers should notice that even shame and anger are included to negative emotions, customers who feel ashamed are different from customers who feel anger in view of approaching consumption. They should conduct their marketing focused on the adaptive consumption to ashamed consumers and do the marketing based on compensatory consumption to angry consumers.

• Journal of Applied Reliability
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• v.8 no.3
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• pp.113-124
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• 2008

In reliability engineering, failure reporting, analysis, and corrective action system (FRACAS) is an useful tool for effective failure reporting and related operations. FRACAS is generally mainly focused on implementation of its closed-loop process, but also includes various related information which has to be effectively managed such as failure types, failure modes, failure mechanisms, and corrective actions. In this study, we adopt and utilize the concept of process knowledge, and create it through abstraction of FRACAS information. At each step of closed-loop process, the necessary type of knowledge, priority and usability are clearly defined. This study also suggests corresponding management tools such as business process management system, knowledge management system, and their key elements and functions to deal with process knowledge. A prototype system using simple closed-loop process with its process knowledge is presented to demonstrate the feasibility of the proposed work.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.3
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• pp.78-89
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• 2022

The purpose of this study was to propose useful suggestion by analyzing preventive replacement policy under which there are minor and major failure. Here, major failure is defined as the failure of system which causes the system to stop working, however, the minor failure is defined as the situation in which the system is working but there exists inconvenience for the user to experience the degradation of performance. For this purpose, we formulated an expected cost rate as a function of periodic replacement time and the number of system update cycles. Then, using the probability and differentiation theory, we analyzed the cost rate function to find the optimal points for periodic replacement time and the number of system update cycles. Also, we present a numerical example to show how to apply our model to the real and practical situation in which even under the minor failure, the user of system is not willing to replace or repair the system immediately, instead he/she is willing to defer the repair or replacement until the periodic or preventive replacement time. Optimal preventive replacement timing using two variables, which are periodic replacement time and the number of system update cycles, is provided and the effects of those variables on the cost are analyzed.

• Journal of Industrial Convergence
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• v.18 no.6
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• pp.1-7
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• 2020

In this study, we hypothesized that the needs for start-up support services may vary depending on the founder's psychological characteristics, such as self-efficacy or his attitude toward uncertainty. To verify this, a survey was conducted on the founders of 86 companies located in Business Incubators at Seoul and Daejeon and an empirical analysis was conducted based on the data. According to the analysis, the higher the self-efficacy of the founder, the more active he expressed his willingness to accept the start-up support service, which aims to provide start-up zones to busy areas outside the university. While the founder, who has experienced failure in the past, responded positively to attracting customers located outside the university. The results of this study supported the hypothesis and suggest that differentiated start-up support services should be designed by including not only characteristics at the level of start-up companies, such as industries and growth stages, but also the psychological characteristics of start-ups in important consideration.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.5 no.4
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• pp.753-760
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• 2015

The Korean wine market is growing year by year recently especially in Off-trade market. It shows not just a part of the very few consumer-driven trend. The purchases of wine is always not so easy because the risk factors and failure points occur when buying wines. Most of wine consumers feel difficulties when buying wines at phase of previous step, buying step and after buying step. Wine consumers can be divided into the wine experts, wine lovers, novices, outsiders. To guide an wine buying with less failures to each representative of wine consumer characteristics and needs, user persona and scenario for the reduced failure were derived.

• Journal of Information Technology and Architecture
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• v.9 no.2
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• pp.133-142
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• 2012

Gartner predicts that by 2012, 40% of EA programs will be stopped due to poor execution and the failure of delivering business value. An organization needs a practical solution to achieve an EA vision. The EA essential approach should be that of business service and process orientation than systems and IT orientation. We propose an Actionable Enterprise Architecture (AEA) which is based on BPM (Business Process Management) and SOA (Service Oriented Architecture), and connected to service & process orientation and engineering. The architecture proposed provides traceability between service-oriented enterprise architecture and its solution. The proposed architecture can transform enterprise architecture from conceptual to physical levels (solutions) with a service and business process paradigm.