• Journal of Korean Institute of Industrial Engineers
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• v.35 no.3
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• pp.194-202
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• 2009

In this paper, we address an optimization problem and a case study for minimizing the cost of inspections incurred throughout an inspection system, which includes a K-stage inspection system, a source inspection shop, and a re-inspection shop. In order to formulate the inspection cost function, we make a time-based flow analysis between nodes (or shops), and derive the limiting sizes of flows between nodes and limiting defective rates by solving a set of nonlinear balance equations. It turns out that the number of items reworked throughout the inspection system is invariant irrespective of the defective rate of items moved through the K-stage inspection system. Hence we define the inspection cost as the total number of items inspected, and we provide an enumeration method for determining an optimal value of K which minimizes the number of items inspected.

• Journal of Industrial Technology
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• v.9
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• pp.51-56
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• 1989

A methodology for determining optimal sampling plans for Bayesian multiattribute curtailed inspection models is proposed, whereby sampling inspection is terminated as soon as the disposition of the inspection lot is determined. An iterative solution procedure is developed for obtaining optimal multiattribute acceptance sampling plans under cuntailed sampling inspection.

• Journal of Korean Institute of Industrial Engineers
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• v.19 no.4
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• pp.115-123
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• 1993

This paper presents an alternative inspection method for counting items of a lot(or kit) in production lines or distribution centers. In this inspection, lots are weighed instead of counting all items of the lots in order to reduce the effort required for the 100% manual counting inspection. Inspection errors of this inspection procedure are analyzed and the impact of the variability of item weights on inspection errors are investigated. Two approaches, the cost assessment approach and the bicriterion decision making approach, are presented for the implementation of this inspection procedure.

• Journal of Korean Institute of Industrial Engineers
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• v.27 no.3
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• pp.297-304
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• 2001

Procurement decisions for inspection equipment are often made heavily based on the initial purchase price instead of the effects of inspection cost, equipment calibration and utilization over the lifetime. Cost of ownership(COO) models that take into account all of these cost factors together have been developed focusing on a single quality characteristic. In modern manufacturing environment, inspection equipment often can deal with more than one quality characteristic simultaneously. In this paper, we propose the revised COO model for the economic evaluation of the inspection equipment that can accommodate multiple quality characteristics. We also employ an engineering economy model to compare equipments with different life span. Software is developed for handy comparison of the COO of alternative equipments along with sensitivity analysis far the optimal procurement decision.

• Journal of Industrial Technology
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• v.3
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• pp.27-32
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• 1983

This paper develops and provides formulas for calculating the Average Outgoing Quality and the Average Total Inspection for nine different sample/rest-of-lot disposition policies in which rectifying multiple sampling inspection by attribute can be carried out. The formulas are considered for perfect inspection as well as error-prone inspection.

• Journal of Korean Society for Quality Management
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• v.22 no.4
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• pp.40-58
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• 1994

Some systems such as early warning system should be inspected occasionally in order to detect failures. If the system is inspected too frequently, inspection cost increases. On the other hand, if the number of inspections is reduced too much, the undetected system downtime cost increases. Thus, it is of interest to find effective inspection schedule, which minimizes the sum of inspection and downtime costs. When the system has increasing failure rate, inspection intervals get shorter as time goes on. But a common practice is to inspect the system at predetermined periodic intervals. In this paper, periodic inspection policy and a modified periodic inspection policy are considered. The modified policy is easily applicable and cost-effective. Some numerical examples are included in order to explain the modified inspection ploicy and its cost performance.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.111-114
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• 2003

In this paper, an industrial electric endoscope is implemented. Most industrial endoscope that used in domestic are imported and the equipments are divided into several parts. So these endoscopes spend a lot of time, labor and inspection cost on inspection process. This research is accomplished to solve above mentioned weak points and to improve previous inspection systems into embedded systems.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.10 no.15
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• pp.33-38
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• 1987

In establishing Multi-Stage Machining process inspection procedures, however, where costs of inspection md defective products are often directly measurable, a better method for formulating inspection plans is available. If one of the primary interest of a manufacturing concern is to maximize profits, then optimal inspection plans ought to be selected so as to minimize costs. This paper is aimed to find a methodology of optimal inspection planning in Multi-stage Machining process and to develope a proper algorithm.

• Journal of the Korean Society of Safety
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• v.16 no.4
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• pp.175-181
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• 2001

In compliance with the Industrial Safely and Health Acts, the owners/users have performed self-inspection at regular intervals to secure safety in the use of hazardous machinery, equipment and facilities However, securing safety, which is the goal of self-inspection, has not been thoroughly understood in most small businesses and factories. The objective of this research is to analyze the importance and effects of self-inspection in preventing accidents in businesses and factories that use hazardous machinery and facilities. The result shows that self-inspection has made a good contribution to the prevention of accidents. Most businesses and factories that responded the survey answered they have improved safety in the use of machinery and facilities through self-inspection, though the ways of self-inspection were not all the same. However, the result also reveals that there are rooms for further improvement in the areas of self-inspection intervals, self-inspection methods and the selection of self-inspection objects. This improvement is necessary to improve the effect of self-inspection and to minimize regulations of the government on business activities.

• Proceedings of the ESK Conference
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• 1992.10a
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• pp.90-95
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• 1992

In this study, the application of fuzzy hierarchical analysis for modeling the inspection tasks with respect to the the improtances of the cognitive factors is considered and it's validity in cognitive researches is confirmed. The results of the relative importance of various cognitive factors can be served as a selection criteria for efficient inspection performance and the information of skilled learning for a inspection training program.