• 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.24 no.2
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• pp.279-285
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• 1998

A quality inspection procedure interchangeably using the performance and screening variables is proposed. At the start of the inspection, the performance variable is measured for all items. As soon as i consecutive items are found to be free of defects, the screening variable is measured instead of the performance variable. If an item is rejected, the inspection based on the performance variable is resumed. All nonconforming items found in the inspection are either reworked or replaced with conforming items. It is assumed that the performance variable is dichotomous, and the screening variable given the performance variable is normally distributed with known mean and variance. The average outgoing quality (AOQ) expression is derived, and the methods of finding the inspection procedure with a specified average outgoing quality limit (AOQL) are presented.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.5
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• pp.411-414
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• 2008

OPC is the preferred communication standard for sharing process control data at all levels of the enterprise and becomes the global standard, sends/receives the data with PLC programs of inspection system via network, and manages various data using OPC server. In this paper, we introduce the developed OPC client system for FPD inspection system with OPC server. To control inspection system through OPC server, we have developed libraries which consist of stage driver, switch driver, microscope driver, image processing, alignment, and task management modules. Also we have developed the test program to verify all functions precisely. We describe the mechanism of inspection system, OPC connection method, and programs.

• International Journal of Precision Engineering and Manufacturing
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• v.7 no.1
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• pp.30-34
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• 2006

Recently, there has been an increasing demand for computer-vision-based inspection and/or measurement system as a part of factory automation equipment. In general, it is almost impossible to check the fault of all parts, coming from part-feeding system, with only manual inspection because of time limitation. Therefore, most of manual inspection is applied to specific samples, not all coming parts, and manual inspection neither guarantee consistent measuring accuracy nor decrease working time. Thus, in order to improve the measuring speed and accuracy of the inspection, a computer-aided measuring and analysis method is highly needed. In this paper, a computer-vision-based pipe inspection system is proposed, where the front and side-view profiles of three different kinds of pipes, coming from a forming line, are acquired by computer vision. And the edge detection is processed by using Laplace operator. To reduce the vision processing time, modified Hough transform is used with clustering method for straight line detection. And the center points and diameters of inner and outer circle are found to determine eccentricity of the parts. Also, an inspection system has been built so that the data and images of faulted parts are stored as files and transferred to the server.

• 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.

• Journal of the Semiconductor & Display Technology
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• v.16 no.2
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• pp.1-8
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• 2017

The visual inspection of electronic parts consists of two steps: automatic visual inspection and verification inspection. In the stage of a verification inspection, the human inspector sequentially inspects all the areas which detected in the automatic inspection. In this study, we propose an algorithm to determine the order of verification inspection by Bayes inference well known in the field of machine learning. This is a method of prioritizing a region estimated to have a high probability of defect using experience data of past inspection. This algorithm was applied to the visual inspection of ultraviolet filters to verify its effectiveness. As a result of the comparison experiment, it was confirmed that the verification inspection can be completed 30% of the conventional method by adapting proposed algorithm.

• Journal of Auto-vehicle Safety Association
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• v.12 no.3
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• pp.7-12
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• 2020

This paper has presented the headlight inspection standards and methods of two-wheeled motorcycles considering Korean Motor Vehicle Safety Standards (KMVSS), Korean Motor Vehicle Inspection Standards (KMVI) and the inspection standards of the International Motor Vehicle Inspection Committee (CITA). As a result of analyzing the headlight luminous intensity test result with fixed inspection equipment, 21% does not meet the inspection standard proposed in this study, and 33.3% in mobile inspection equipment does not meet. The average luminous intensity of motorcycle less than 50 cc is 8,340 cd, so all the lightweight small sized motor cycles do not meet the proposed headlight inspection standard.

• IE interfaces
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• v.24 no.1
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• pp.87-96
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• 2011

In this paper, we address an optimization problem for minimizing the inspection and rework cost in an inspection-rework system, which forms a network of nodes including a K-stage inspection system, storage areas for items, a source inspection shop, and a re-inspection shop. We assume that (n, 0) acceptance sampling is performed in the source inspection shop and that only 100(1-r)% of items of rejected lots are re-inspected in the re-inspection shop. Since all the nodes are interrelated, in order to formulate our steady-state objective function, we make a steady-state network flow analysis between nodes, and derive both the steady-state amount of flows between nodes and the steady-state fraction defectives by solving a nonlinear balance equation. Finally we provide some fundamental properties and an enumeration procedure for determining the optimal values of (K, r) which both minimizes our objective function and attains a given target average outgoing quality.

• Nuclear Engineering and Technology
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• v.51 no.2
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• pp.618-625
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• 2019

When newcomer countries consider a nuclear power programme, it is recognized that the most important organizations are the Nuclear Energy Programme Implementing Organization (NEPIO), the regulator, and an operating organization. Concerning the number of construction delays these days, one of the essential organizations is an Authorized Inspection Agency (AIA). According to World Nuclear Industry Status Report, all of the reactors under construction in eight out of the thirteen countries have experienced delays. Globally, the Flamanville 3 project and Sanmen Unit 1 are 6.5 years and 5 years late respectively. One of the major reasons of delay is due to inappropriate manufacturing and inspection on safety class components. The recommendations are made to develop such an organization: (i) find existing inspection organizations in relevant industries, (ii) contract with expatriates who have experience on nuclear inspection, (iii) develop a legislative framework to authorize the inspection organization with enforcement, (iv) include a contract clause in the BIS for developing the AIA, (v) hold training programmes from vendor country, (vi) during manufacturing and construction, domestic AIA shall be involved.

• Journal of the Ergonomics Society of Korea
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• v.30 no.5
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• pp.645-650
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• 2011

Objective: The aim of this study is to design a sampling inspection plan with human error which is changing according to inspection time. Background: Typical sampling inspection plans have been established typically based on an assumption of the perfect inspection without human error. However, most of all inspection tasks include human errors in the process of inspection. Therefore, a sampling inspection plan should be designed with consideration of imperfect inspection. Method: A model for single sampling inspection plans were proposed for the cases that visual inspection error rate is changing according to inspection time. Additionally, a sampling inspection plan for an optimal inspection time was proposed. In order to show an applied example of the proposed model, an experiment for visual inspection task was performed and the inspection error rates were measured according to the inspection time. Results: Inspection error rates changed according to inspection time. The inspection error rate could be reflected on the single sampling inspection plans for attribute. In particular, inspection error rate in an optimal inspection time may be used for a reasonable single sampling plan in a practical view. Conclusion: Human error rate in inspection tasks should be reflected on typical single sampling inspection plans. A sampling inspection plan with consideration of human error requires more sampling number than a typical sampling plan with perfect inspection. Application: The result of this research may help to determine more practical sampling inspection plan rather than typical one.