• Proceedings of the ESK Conference
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• 1995.04a
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• pp.3-14
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• 1995

To investigate the effect of illumination conditions on visual inspection performance for TV panel glasses, three dependent variables, inspection time, error, and preference , were measured and analyzed through two consecutive experiments. The first experiment for reflection inspection was conducted using two independent variables, position and brightness. The second experiment for transparent inspection was made using two independent variables, height and brightness. The summary of the results of the experiment for reflection inspection are as follows ; The inspection performance of the position right above the subject (Position 1) was the best among the conditions in terms of errors, while the performance of the position slightly in front of and above the subject(Position 2) was the best in terms of inspection times. Inspection time was statistically different according to the brightness conditions specifically at the position in front of the subject(Position 3). The results of the second experimen for transparent inspection are that the inspection performance at medium height (Height 2) was the best among the three conditions in terms of errors while the performance at lower height(Height 3) was the best in subject preference. Based upon both results with respect to actual field conditions, two alternative inspection station designs were proposed for each lighting conditon.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.205-213
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• 2001

The condition assessment of bridges is one of the important procedures in the safety evaluation of the structures. The current inspection guideline is rather ambiguous and vague so that the inspection results based on the existing guidelines are highly subjective and varing from person to person and even day to day for a given person. It is therefore, necessary to improve the current inspection criteria in order to provide consistent results in safety assessment. To circumvent possible inconsistencies in inspection and rating of bridge components, the revised criteria have been proposed in this study. The proposed guideline and criteria may be efficiently used for the realistic and consistent assessment of bridge structures.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.10
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• pp.1030-1035
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• 2014

Machine vision inspection systems have replaced human inspectors in defect inspection fields for several decades. However, the inspection results of machine vision are often affected by small changes of illumination. When small changes of illumination appear in image histograms, the influence of illumination can be decreased by transformation of the histogram. In this paper, we propose an enhanced histogram matching algorithm which corrects distorted histograms by variations of illumination. We use the resolution resizing method for an optimal matching of input and reference histograms and reduction of quantization errors from the digitizing process. The proposed algorithm aims not only for improvement of the accuracy of defect detection, but also robustness against variations of illumination in machine vision inspection. The experimental results show that the proposed method maintains uniform inspection error rates under dramatic illumination changes whereas the conventional inspection method reveals inconsistent inspection results in the same illumination conditions.

• Journal of the Korea Safety Management & Science
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• v.14 no.4
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• pp.169-175
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• 2012

Self-Inspection is being used in the workplace hazardous, dangerous machinery and equipment to build capacity for the voluntary safety risks due to use of machinery and prevention of industrial accidents that inspect facilities for safety issues, is to check. However, December 31, 2008 as part of Article 36 of the Occupational Safety and Health Act (safety inspection), the financial vanish as the self-test, Safety inspection program has been changed., In each individual workplace that creates its own standards and regulations to use the existing inspection system is in some cases. This study is located in the southeast industrial complex as a risk reducer manufacturer, machine-based target zones in S Corp owns most of the crane based on the results of the tests is to analyze the problem. Then check the results - to bring its measures and information you need to know for sure is to propose.

• Journal of the Korean Professional Engineers Association
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• v.34 no.2
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• pp.14-18
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• 2001

The primary cooling piping of HANARO is classified as safety class 3, seismic class 1 and quality class Q. This piping as safety related feature has been designed, manufactured and tested in accordance with ASME SEC. Ⅲ, DIV 1, Class 3. In October of 2000, the first step of the in-service inspection for this piping was carried out in accordance with ASME SEC. XI. This describes the results of the Inspection including the preparation of inservice inspection plan and inspection method. It is verified through the results that the safety related piping is maintained the mechanical and structural Integrities.

• 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.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1285-1290
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• 2000

The inspection of bridge condition is of extreme importance. Current inspection codes for bridge inspection are vague and uncertain. So, the results are highly subjective and different from person to person and even day to day for a given person. To circumvent possible inconsistencies in inspection and rating of bridge components, the revised inspection guidelines have been proposed.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1684-1688
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• 2005

In this paper, authentication technologies for X-ray inspection images in container merchandises are introduced and a method of authentication for X-ray inspection images is proposed. Until now, X-ray images of container merchandises have been managed without any authentication of inspection results and environments, it means that there was no any action for protection of illegal copy and counterfeiting of X-ray images from inspection results. Here, authentication identifies that who did inspect container X-ray images and, whether the container X-ray images were counterfeited or not. Our proposed algorithm indicates to put important information about X-ray inspection results on an X-ray image without affecting quality of the original image. Therefore, this paper will be useful in determining an appropriate technology and system specification for authentication of X-ray inspection images. As a result of experiment, we find that the information can be embedded to X-ray image without large degradation of image quality. Our proposed algorithm has high detection ratio by Quality 20 of JPEG attack.

• Industrial Engineering and Management Systems
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• v.16 no.1
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• pp.1-21
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• 2017

This paper discusses a reverse supply chain (RSC) which consists of the process flows from procurement of used products collected from a market, through remanufacturing products from the used products, to sales of the products in a market. In general, it is conceivable for the RSC to face the uncertainty in quality of used products collected from a market. Inspection is one of efficient methods to deal with the problem regarding quality of used products. However, there is a trade-off between inspection cost and inspection accuracy. This paper focuses on the following five types of inspection: (1) 100% inspection, (2) sampling inspection, (3) sampling inspection with screening of rejected lots, (4) sampling inspection with screening of acceptable lots, and (5) no inspection, and determines the optimal operation consisting of the optimal number of procured used products and the optimal inspection policy. Numerical analysis clarifies not only how changes of conditions of the RSC affect the manufacturer's optimal operation but also features of each inspection type. In addition, from the results of numerical analysis, this paper shows the usability to add the proposed inspection in this paper, the sampling inspection with screening of acceptable lots, to choices of inspection type.

• Journal of the Korean Geosynthetics Society
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• v.13 no.4
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• pp.133-141
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• 2014

This study was carried out to establish the database system by using the safety inspection and in-depth inspection results for infrastructures such as bridges, tunnels, dams, and water supplies. A classification system of each facility was proposed by standardizing items for inspection & diagnosis in order to automatize work process. Also, it justifies data structure based on database from pre-investigation to field survey, evaluation of facilities, and report making. In addition to this, it suggests improvement plans of relative regulations and guidelines such as Facility Management System(FMS), operational regulation, and inspection detailed guideline to make inspection result database of infrastructures which can be used effectively.