• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1734-1735
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• 2011

In case of inspection on aluminum castings, traditional RT (Radiographic Testing) method have been utilized for its advantages in interpretation, cost and perpetual storage. But it has disadvantages like time consumption in film processing, low efficiency in storage and environmental pollution. In this thesis, a DRS (Digital Radiography System) utilizing X-Ray TDI Camera (Time Delay and Integration Camera) is developed. Inspections on aluminum castings are performed using the developed Digital Radiography System, DRS and reviewed if newly developed system can substitute for the traditional method.

• Journal of Korean Society for Quality Management
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• v.16 no.2
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• pp.82-91
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• 1988

This study is concerned with the development of the economic sampling inspection plan when it is possible to carry out a nondestructive screening inspection for the rejected lots by substitutive characteristics closely related to the original quality characteristic. It is assumed that the probabilities of those errors depend linearly on the fraction defective of the process. The inspection policies considered are as follows: take a random sample of size n from the lot of size N and perform a destructive test on the sample. If the number of the defective items is not greater than a critical number C, accept the lot. Expected cost functions are obtained when the process average can be considered to follow a beta distribution and the way of finding the optimal values of (n, c) is to be explored.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.1
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• pp.82-88
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• 2005

The damage inspection of container surface is performed by the expert inspectors at the container terminal gate of harbor. In this paper, we substitute the expert's capability with the damage inspection system using the artificial intelligent control algorithm and vision system, so we can improve the work environment and effectively decrease the inspection time and cost. Firstly, using six CCD cameras attached to the terminal gate, whole container is partially captured according to eleven sensors aligned with the entering direction of container. Captured partial images are inspected by the fuzzy system which the expert's technology is embedded. Next, we compose partial images to be a complete container image through the correlation coefficient method. Complete container image is saved to solve future troublesome problems. In this paper, the effectiveness of the proposed system was verified through the field test.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.2
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• pp.293-298
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• 2016

Recently, interests for maintenance of transmission tower are increasing to extend life of structures and reduce maintenance cost. However, existing classical diagnosis method of corrosion deteriorated degree on the transmission tower steel members, visual inspection, has a problem that error often due to difference of inspector's individual knowledge and experience. In order to solve the problem, this study carried out to develop the corrosion deterioration inspection tool for transmission tower steel members. This tool is composed of camera equipment and computer-aided diagnosis system. We standardized the photographing method by camera equipment to obtain suitable pictures for image processing. Diagnosis system was designed to evaluate automatically degree of corrosion deterioration for member of transmission tower on the basis of the RGB color image processing techniques. It is anticipated that developed the corrosion deterioration inspection tool will be very helpful in decision of optimal maintenance time for transmission tower corrosion.

• Journal of the Semiconductor & Display Technology
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• v.10 no.1
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• pp.17-22
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• 2011

LEDs(Light Emitting Diodes) are becoming widely used and increasingly in demand. Quality inspection of the LEDs has become more important. Two-dimensional inspection systems are limited in inspection capability, so threedimensional(3-D) inspection systems are needed. In this paper, a cost-effective and simple 3-D measurement system of LED packages using phase measuring profilometry(PMP) is proposed. The proposed system uses a pico projector to project sinusoidal fringe patterns and to shift phases instead of piezocrystal. It was evaluated using extremely accurate gauge blocks, yielding excellent repeatability of about 12 um(3-sigma). 3-D measurements of various LED packages were performed to demonstrate the applicability and efficiency of the proposed system.

• Journal of the Korean Society of Safety
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• v.20 no.3 s.71
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• pp.14-18
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• 2005

The ultrasonic handy scanner to be developed in this research is a nondestructive inspection equipment with various facility. The ultrasonic inspection is the technique area which apply range is increasing greatly with IT. The purpose of this research is development of a ultrasonic handy scan inspection device with the utility in a work spot. The ultrasonic handy scanner to be developed with portability in this research is able to carry out the spot inspection. It can contribute to the quality improvement, cost reduction and safety design.

• The Journal of Korea Robotics Society
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• v.17 no.2
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• pp.216-220
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• 2022

This paper proposes an inspection robot that can operate on a single square rail. Various inspection robots have been developed to identify emergency situations in industrial environments, such as those involving fires or individuals with cardiac arrest. Because the robots must operate in wide areas and long tunnels, they are designed to move along a rail installed on the ceiling. Double rail track are typically used to ensure the stability of robot movement. However, the cost for installing a double rail track is nearly two times that for a single rail track. Moreover, it is challenging to install double rail tracks while ensuring the same curvature and interval between the two rails. Therefore, in this study, an inspection robot that operate on a single square rail track is developed. To ensure stable movement in the longitudinal and lateral directions, two passive guide parts are used, and the main active wheel is allowed to move on the upper side of the square rail. The prototype was manufactured, and experiments were performed for different robot velocities.

• 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 the Korean Society of Safety
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• v.22 no.6
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• pp.35-40
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• 2007

As a way of improving the safety of the chemical facilities, the risk based-inspection(RBI) was executed for the facilities of the applied petrochemical plant using KS-RBI Ver. 3.0 program developed based on the API-581 based resource document(BRD). From an evaluation result of KS-RBI program, we could find the evaluation of the process safety management(PSM) for the applied plant, risk of the applied process, risk of static facilities and pipes, and the demage mechanism of the facilities. Also, we could suggest a proper inspection plan(frequency and method of inspection) using the calculated risk and the status of the facilities. Therefore, the applied plant could be achieved a reduced inspection cost by an extension of inspection frequency, improved productivity, improved reliability of the facilities, and a computerized history management.

• Journal of the Korean Institute of Gas
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• v.15 no.1
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• pp.15-21
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• 2011

Cost-benefit analysis (CBA) has been performed in order to decide whether the ILI (in-line inspection) suggested as risk mitigation measure (RMM) from quantitative risk assessment is reasonably practicable. As a result of CBA, we could find out the reasonable intervals of implementation of ILI. In order to assess the benefit, value of preventing a fatality (VPF), which measures value of human life, has been used. The adequate VPF figure of high pressure urban gas pipelines for CBA used in this paper is two billion won. As a result of 2 case studies, we found that the most reasonable intervals of ILI suggested as RMM were 13 years or 15 years.