• Industrial Engineering and Management Systems
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• v.11 no.4
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• pp.390-396
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• 2012

The present paper extends the idea of tightened-normal-tightened sampling scheme to group acceptance sampling plans under the time truncated life tests. We consider three famous distributions that are widely used in the area of reliability such as the generalized exponential distribution, the Weibull distribution, and the Birnbaum-Saunders distribution in the proposed sampling plan. The plan parameters are determined such that the producer's risk and the consumer's risk are satisfied at the specified median life. Extensive tables showing plan parameters are provided at various values of the experiment time and the consumer's risk for each of three distributions for the practical use. Some examples are given to illustrate the procedure of the proposed plan.

• Journal of the Korea Society for Simulation
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• v.9 no.2
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• pp.75-87
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• 2000

In this paper, nonstationary multiple sampling plans are discussed which are difficult to solve by analytical method when there exists dependency between the sample data. The initial solution is found by the sequential sampling plan using the sequential probability ration test. The number of acceptance and rejection in each step of the multiple sampling plan are found by grouping the sequential sampling plan's solution initially. The optimal multiple sampling plans are found by simulation. Four search methods are developed U and the optimum sampling plans satisfying the Type I and Type ll error probabilities. The performance of the sampling plans is measured and their algorithms are also shown. To consider the nonstationary property of the dependent sampling plan, simulation method is used for finding the lot rejection and acceptance probability function. As a numerical example Markov chain model is inspected. Effects of the dependency factor and search methods are compared to analyze the sampling results by changing their parameters.

• Proceedings of the Safety Management and Science Conference
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• 2008.11a
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• pp.161-165
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• 2008

This paper introduces three continuous sampling plans by attribute. Revised KS standards for acceptance samplings such as KSA ISO 2859-3, 4 : 2001 and 21247 : 2007 are presented. These plans are based on skip-lot, DQL(Declared Quality Level) and VL (Verification Level).

• Communications for Statistical Applications and Methods
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• v.18 no.4
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• pp.403-411
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• 2011

This paper deals with a group acceptance sampling plan for time truncated tests which are based on the total number of failures from the whole group assuming that the life time of an item follows the Dagum (inverse Burr) distribution. This study is developed when a multiple number of items as a group can be tested simultaneously in a tester. The minimum number of groups required for a given group size and acceptance number is determined such that the producer and consumer risks are satisfied simultaneously at the specified quality level, while the termination time and the number of testers are specified. Comparisons are made between the proposed plan and the existing plan on the basis of size of the groups. Two real examples are provided.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.9
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• pp.35-43
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• 2021

This study aims to investigate factors affecting eBook acceptance and learning outcomes among students experiencing online distance learning. As conventional textbooks are now switched into eBooks, the effects of contextual factors including lecturer, student computer competency, content and design of the course, access ability, infrastructure, and university support on eBook acceptance and learning outcome needs to be evaluated. The sample of this study is represented by students at the Universiti Teknologi MARA, City Campus Melaka, undertaking 'strategic management course'. Non-probability random sampling was selected as the sampling technique and a purposive sampling method was chosen to select the samples. The samples comprised 171 students randomly selected through Google Form. The questionnaire data was analyzed by using PLS-SEM. The results indicated that these factors contributed 62.3% variations in the eBook acceptance and 67.1% variations in the learning outcomes. The strongest factor affecting both dependent variables was content and design of course. Managerial implication suggested that the content for all courses taught through the eBook platform needs to be revisited and improved in accordance with the mode of online deliverance. Tutorial on how to navigate the eBook platform is important to all users as this would enhance acceptance and produce better learning outcomes among students.

• Journal of the Korean Operations Research and Management Science Society
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• v.21 no.1
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• pp.115-129
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• 1996

A reliability Acceptance Sampling Plan (RASP) is developed for testing the exponential mean lifetime under the periodic (i. e., equally-spaced) inspection and Type I censoring. Under the periodic inspection, the exact sampling distribution of maximum likelihood (ML) estimator of mean can not be derived. Hence sample size and acceptance criterion are determined by the algorithm proposed on the basis of Monte Carlo simulation such that the producer's and consumer's risks are satisfied for given censoring time and number of inspections. In addition, the developed RASP is compared in terms of sampling size, OC curve, and expected completion time. The effects for the RASP by the chosen inspection scheme are also discussed.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.10a
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• pp.187-193
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• 1996

This paper presents a new approach to modify the traditional method for sampling inspectionby variables to suit undesired measurement conditions. On the basis of a systematic analysis of the effects of measurement errors on different types of acceptance schemes this paper gives two modified equations for revising the sampling size η and the acceptability constant $textsc{k}$ to form a new acceptance scheme (η'$textsc{k}$) under undesired measurement conditions. It has proved that the new method is suitable to different types of sampling inspection by variables including that for mean value and that for percent defective. The new acceptance scheme based on the proposed technique provides an engineering feasibility to replace the traditional scheme to suit undesired measurement conditions.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.15 no.25
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• pp.75-82
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• 1992

Standard acceptance sampling plans models the production pricess as a sequence of independent identically distributed Beruoulli random variables. However, the quality of items sampled sequentially from an ongoing production process of ten exhibits statistical dependency that is not accounted for in standard acceptance sampling plans. In this paper, a dependent production process is modelled as an ARMA process and as a two-state Markov chain. A simulation study of each is performed. A comparison of the probability of acceptance is done for the simulation method and for the approximation method.

• Journal of Korean Society for Quality Management
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• v.19 no.2
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• pp.86-95
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• 1991

Empirical Bayes estimation of the binomial parameter ${\theta}$ is considered when the sample size in each component problem is random. The result is applied to the lot acceptance sampling problem in the presence of various kinds of costs including cost for sampling.

• Journal of Korean Institute of Industrial Engineers
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• v.20 no.1
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• pp.15-25
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• 1994

The Bayesian approach to reliability acceptance sampling has several advantages over the non-Bayesian approach. For instance, the former usually requires less amount of testing time and smaller sample sizes than the latter. In this article, a Bayesian acceptance sampling plan(ASP) based on a failure-free period life test is developed under the assumption of exponential lifetime distribution, and is compared with the corresponding Bayesian hybrid ASP in terms of the expected completion time. It is found that the proposed ASP tends to have a smaller expected completion time than the Bayesian hybrid ASP as the prior assessment of the reliability of a lot becomes optimistic, and vice versa. Tables of failure-free period Bayesian ASP's are also included.