• Journal of Korean Society for Quality Management
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• v.19 no.2
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• pp.63-77
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• 1991

Currently the problem of air pollution caused by the motor vehicle emission is one of the most serious problems to be solved. Thus we needed the inspection method and technical innovation constraining the motor vehicle emission. In order to establish the more reasonable certified test, the multivariate sequential rectifying inspection plan designed in this paper has been applied to the domestic vehicles by analyzing the statistic characteristics of the emission distribution. This inspection method is designed to satisfy the evaluation measure constraining domestic vehicle emission, and it serves the defect rectifying system and performance certification of catalytic converts. As the prior parameter for the domestic vehicles, we used the data for the catalytic converts which passed the certified test excuted by the EPK. For the case of engine test, we used those data which passed the certified test of domestic vehicles. The multivariate sequential rectifying inspection plan of the vector parameter is able to minimize the average sample number and increase the pass probability of operating characteristic curve.

• Journal of Korean Society for Quality Management
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• v.23 no.4
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• pp.74-89
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• 1995

In recent years, the safety of customers and the demand for rights to be protected from the risk have become stronger than ever day by day, and the function concerning product liability(PL) and quality assurance(QA) has been emphasized. Basically these functions can be obtained by inspection and there is the single rectifying sampling inspection for attribute (KSA-3105) as an existing method. But we can not say this method is good enough because of limitations in the range of applications and the approximate design of inspection methods which can not meet the rapidity and accuracy of quality information transfer according to the maturity of information period. Therefore, in this paper, a new algorithm is developed which can design the accurate inspection method by using the linear cost function that has not been considered in the existing inspection methods. Also in addition to this, a optimal rectifying sampling inspection plan, contributing to minimize the total costs, can be developed by programming the algorithm developed in this study and it can be applied to any field having many processes almost limitlessly.

• Proceedings of the Safety Management and Science Conference
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• 2011.11a
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• pp.205-211
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• 2011

The papaer reviews four theoretical acceptance sampling plans as OC(Operating Characteristics) curve based inspection, rectifying inspection, switching inspection, and continuous inspection. In addition, the study presents practical limitations of theoretical acceptance sampling by attribute and by variable. Finally, following research also recommends the sampling inspection based on production technology. However, the inspection method requires quality expertise with various experience and implicit knowledge of the field.

• Journal of Korean Society for Quality Management
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• v.17 no.1
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• pp.48-59
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• 1989

The motor vehicle emission is expected to be constrained strongly in the future in accordance with the current policy as to prevention of air pollution. This paper establishes a sequential rectifying inspection plan which satisfies the standard motor vehicle emission for the automobile producers who are currently producting the automobiles with catalytic converts. This plan also considered the constraint of the effective motor vehicle emission by way of rectifying the certification test in the past. In order to evaluate the performance of the inspection plan, the recent certification test data have also been applied. The result of the application has proved that the rectified sequential inspection plan presented in this paper satisfies the standard motor vehicle emission and can be the optimal economic inspection plan. As a result the inspection plan given in this paper will be contributed to constrain the motor vehicle emission most effectively.

• Journal of the Korean Operations Research and Management Science Society
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• v.35 no.1
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• pp.97-109
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• 2010

In this paper, we study a joint design problem of sampling inspections and service capacities for multi-products. Products are supplied in batches after rectifying inspections, that is, rejected lots are 100% inspected and defective products are reworked to good ones. When supplied, all defective products are uncovered through total inspection and returned to service. By exploiting the first and second order properties of the objective function, we identify the optimal inspection policies and service capacities for individual products, and develop allocation algorithms to obtain an optimal allocation of the limited total service capacity to products with the small number of computations.

• Korean Management Science Review
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• v.33 no.3
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• pp.89-103
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• 2016

In this paper, we design sampling inspections and service capacities simultaneously for multi-products. Products are supplied in batches after rectifying inspections, that is, rejected lot is subject to total inspection and defective products are reworked to good ones. When supplied, all defective products are uncovered and returned to service. Particularly, we extend Kim [1] by introducing the fixed costs of providing services and show that the cost function of a product is no longer linear or convex in terms of the level of service provision. We develop a framework for a product to deal with this joint design problem and a dynamic programming algorithm for multi-products which allocates the given number of the total service capacities among products with the considerably smaller computations than the total number of possible allocations.

• Journal of Korean Society for Quality Management
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• v.24 no.4
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• pp.207-223
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• 1996

These days, customers have attached great importance to the function of product liability and quality assurance. In Korea, the single rectifying sampling inspection for attribute (KS A 3105) has been used. But this inspection plan given by tables (KS A 3105) has some defects. There are limitations in the range of applications and irrationality of approximate probability and the double rectifying sampling inspection is not mentioned. Moreover, ATI (average total inspection) does not reflect sampling costs and the loss of nonconforming item. Therefore, the objectives of this study is to develope new algorithms and computer program that provide the optimal sampling inspection plan based on minimum linear costs (single & double inspection plan). The result of this study revealed that the new algorithm is less than KS A 3105 in ATI and basically, double inspection plan is more economical. Also it comes over restrictions in KS A 3105. So, it is definite that the optimal solution can be obtained considering cost factors in manufacturing and sampling process, and costs can be saved in the long term.

• Journal of Korean Society for Quality Management
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• v.15 no.1
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• pp.68-75
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• 1987

A rectifying inspection plan is considered for the case of destructive testing. Screening inspection for rejected lots is performed by some nondestructive testing which is prone to misclassification errors. Apparent defectives found in the screening process is replaced with apparent good items. The plan provides LTPD protection on each individual lot while the sum of the cost of testing and the cost due to producer's risk at process average quality is minimized. A brief discussion on average outgoing quality is also given.

• Journal of Korean Society for Quality Management
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• v.15 no.2
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• pp.55-60
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• 1987

A rectifying inspection plan which assumes a gamma - prior distribution on the lot percent defective is considered. This sampling inspection plan is developed for finite lot sizes with matching OC curves and generated from an initial plan selected from KS A 3102 single sampling by attributes. Comparisons are made with each plan by three examples.

• Journal of Korean Society for Quality Management
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• v.30 no.1
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• pp.74-96
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• 2002

The objectives of this study is to suggest the rectifying sampling inspection plan considering quality cost. Limiting quality level(LQL) plans(also called LTPD plans) and outgoing quality(OQ) plans are considered. The Hald's linear cost model is discussed with and without a beta prior for the distribution of the fraction of nonconforming items in a lot. It is assumed that the sampling inspection is error free. We consider the design of reliability acceptance sampling plan (RASP) for failure rate level qualification at selected confidence level. The lifetime distribution of products is assumed to be exponential. MIL-STD-690C and K C 6032 standards provide this procedures. But these procedures have some questions to apply in the field. The cost of test and confidence level(1-$\beta$ risk) are the problem between supplier and user. So, we suggest that the optimal life test sampling inspection plans using simple linear cost model considering product cost, capability of environment chamber, environmental test cost, and etc. Especially, we consider a reliability of lots that contain some nonconforming items. In this case we assumed that a nonconforming item fail after environmental life test. Finally, we develope the algorithm of the optimal sampling inspection plan based on minimum costs for rectifying inspection and RASP. And computer application programs are developed So, it is shown how the desired sampling plan can be easily found.