• Journal of Korean Society for Quality Management
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• v.21 no.1
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• pp.108-120
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• 1993

In this article an economic life test sampling plan is considered for repairable products when the products in each lot have the same interfailure time distribution, but the mean time between failure (MTBF) of a lot varies from lot to lot according to a known prior distribution. A cost model is constructed which consists of test cost, accept cost, and reject cost. Determination of the optimal plan which minimizes the expected average cost per lot is discussed. Numerical examples are presented to illustrate the use of the proposed sampling plans and sensitivity analyses for parameters of the prior distribution are performed.

• Journal of Korean Society for Quality Management
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• v.51 no.2
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• pp.155-170
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• 2023

Purpose: Nowadays, the risk assessment system is widely used in many industrial and public areas to reduce the possible risks. The system is used to determine the priorities of the government quality assurance works in Defense Agency for Technology and Quality. However, as the risk assessment system is used for other purposes, there are some items that need improvement, and in this study, we propose improvement plans by benchmarking the risk assessment systems of other institutions. Methods: In this paper, first, the procedures of risk assessment system used in many industrial sites were reviewed, and how each institution specialized and applied the system. Afterwards, by benchmarking various risk assessment systems, an improvement plan on how to operate the risk assessment system in the case of government quality assurance for centrally procured military supplies was presented, and practical application cases were presented to prove the usefulness of the improvement plan. Results: The proposed risk assessment system differs from the existing system in five major aspects. First, inputs, outputs, and key performance indicators were specified from the systematic point of view. Second, risk analysis was analyzed in four dimensions: probability of occurrence, impact, detection difficulty. Third, risk mitigation measures were classified, control, transfer, and sharing. Fourth, the risk mitigation measures were realized through document verification, product verification, process verification, and quality system evaluation. Finally, risk mitigation measures were implemented and the effectiveness of the risk mitigation measures was evaluated through effectiveness evaluation. Conclusions: In order for the risk assessment procedure proposed in this study to be applied to actual work, it is necessary to obtain the consent of the person involved in the work due to the increased time for risk identification and preparation of the government quality assurance log, and a change in the information system that performs the actual work is required. Therefore, the authors of this study plan to actively perform internal seminar presentations and work improvement suggestions to apply these research outputs to actual work.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2006.11a
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• pp.392-395
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• 2006

This research tried to observe transition quality of unit plan for public space Korea public operated house since the 1950s. Plane of public-operated house had continually accommodated lifestyle change until present from the late 1950s. "Frontward 3 urface unit 3LDK'composition plans become settle by the representative plane after the 1990s. The process that with special quality change of public space the relation is deep. it is proposed consequently to analyze the space special quality change of the public operated house unit plan style.

• IE interfaces
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• v.19 no.3
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• pp.190-201
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• 2006

With the rapid growth in the demand and supply of web service, the search for superior services has become a prominent issue. Furthermore, much emphasis and attention are being placed on composite web services, where individual services are combined together to form a single workflow to satisfy the demand of the customers. In today's era of excessive expansion of web services, this study intends to propose the execution plan architecture for composite web services to accomplish the following three goals. The first goal is to derive a feasible plan which maximize user satisfaction for composite web services by implementing an execution plan architecture that reflects the Quality of Service criteria. Secondly, this study also aims at analyzing and selecting the indexes that adequately reflects its quality and its nonfunctional property. Finally, this study intends to apply the concept of constraint satisfaction problem and heuristics to reduce the execution duration of the process.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.169-170
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• 2023

Leakage defects account for a significant proportion of defect cases in modular homes. There are factors that can cause leakage defects at each stage, and quality control measures are required to minimize them. An improvement plan to prevent leakage defects was applied from the design drawings to the site of a modular public rental apartment complex in Sejong City 6-3, and a quality control plan was proposed to minimize leakage defects in the remaining process processes.

• Korean Journal of Social Welfare
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• v.64 no.3
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• pp.155-181
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• 2012

The paper aims to improve the quality and validity of community plan using the content analysis on gyeongju-si. To achieve it, the relevant literatures reviewed, and established the basic framework and three criteria of community plan, then adapted these criteria to the gyeongju-si community plan. Findings are like: Firstly, the measurement criteria of validity are clarified into three; vertical consistency on the whole plan's hierarchical structure, horizontal relevancy between the section plans, clearness of statement. Secondly, generally, gyeongju si plan didn't satisfy the criteria of validity. Based on these results, it specifically offers a impoverishment strategy including the guidelines' upgrading.

• Journal of Korean Society for Quality Management
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• v.29 no.3
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• pp.49-65
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• 2001

This paper presents new compromise ALT plan which is applied to situations that true relationship between stress and parameters is not known exactly. The assumed failure distribution of this study is one of location-scale family, i. e., exponential, Weibull, and lognormal distributions which have been ones of the popular choices of failure distributions. The method of applying the stress is constant, and the censoring mechanism is Type I censoring. Compared with existing compromise plans under true simple linear model in terms of statistical efficiency, the efficiency of new compromise plan is better than the corresponding other compromise ones in most cases. For case when true model is quadratic, this plan can be used without any severe loss in statistical efficiency. The proposed new compromise ALT plan is illustrated with a numerical example and sensitivity analyses are conducted to study effects of pre-estimates of design parameters.

• Journal of Korean Society for Quality Management
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• v.24 no.2
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• pp.25-43
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• 1996

This paper presents the optimal and practical constant-stress accelerated life test plans for the lognormal lifetime distribution tinder assumptions of intermittent inspection and Type-I censoring. In an optimal plan, the low stress level and the proportions of test units allocated at each stress are determined under given inspection scheme and number of inspections such that the asymptotic variance of the maximum likelihood estimator of a certain quantile at use condition is minimized. Although the practical plan adopts the same design criterion, it involves three rather than two overstress levels in order to compromise the practical deficiencies of the optimal plan. Computational experiments are conducted to choose an allocation plan and a inspection scheme of the practical plan and to compare with test plans over a range of parameter values.

• Journal of the Korean Professional Engineers Association
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• v.21 no.1
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• pp.35-41
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• 1988

• Journal of Internet Computing and Services
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• v.20 no.6
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• pp.37-46
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• 2019

A test plan is a high level document detailing objectives, processes, schedules and so on for verifying a developed software. And a test strategy, a component of a test plan, is about how to test software products to guarantee its quality and find bugs in the software in advance. Therefore, establishing effective and suitable test strategies is important for elaborating test processes. However, these tasks are difficult for project managers who write a test plan if they were not trained well in software test processes. And mis-designed test strategies will also mislead entire testing behaviors that testers would do. As a result, there would be a low quality software product in the end. To solve this problem, we propose a new test strategy reuse technique in this paper. By utilizing test plans of already completed software development projects, we lead test planer to reuse suitable and effective test strategies which were used in previous projects. To do so, we evaluate existing test strategies by utilizing ISO/IEC 25010 quality model for evaluating the suitability of test strategies and also use effectiveness metrics for test strategies. And from these evaluations, we predict completeness of new test plan that is written by reused test strategies. It can help the project manager to write an appropriate test plan for the quality characteristics which are selected as objectives for testing and software product. We show the possibility of our approach by implementing a prototype into the existing framework in a case study.