• Journal of Korean Institute of Industrial Engineers
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• v.36 no.2
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• pp.108-116
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• 2010

The maintenance of a deteriorating system is often imperfect. Previous studies have shown that the imperfect preventive maintenance (PM) can reduce the wear out and aging effects of deteriorating systems to a certain level between the conditions of as good as new and as bad as old. In this paper, we employ the concept of the improvement factor in investigating two optimal PM policies; failure limit policy and periodic PM policy. We redefine the improvement factor model as a function of the cost of PM, using this concept, we derive the conditions of optimal PM policies and formulate expressions to compute the expected cost rate. Based on this information, the determination of the maintenance policies which minimize the cost rate is examined. Numerical examples for the Weibull distribution case are also given.

• Management & Information Systems Review
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• v.36 no.4
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• pp.21-32
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• 2017

Motivated by the recent cases of negligent social responsibility as manifested by foreign luxury fashion brands in Korea, this study investigates whether agency costs depend on the sustainability of different types of corporate governance. Agency costs refer either to vertical costs arising from the relationship between stockholders and managers, or to horizontal costs associated with the potential conflicts between majority and minority stockholders. The firms with luxury fashion brand could spend large sums of money on maintenance of magnificent brand image, thereby increasing the agency cost. On the contrary, the firms may hold down wasteful spending to report a gaudily financial achievement. This results in mitigation of the agency cost. Agency costs are measured by the value of the principal component. First, three ratios are constructed: asset turnover, operating expense to sales, and earnings before interest, tax, and depreciation. Then, the scores of each of these ratios for individual firms in the sample are differenced from the ratios for the benchmark firm of S-OIL. S-OIL was designated as the best superior governance model firm for 2013 by CGS. We perform regression analysis of each agency cost index, luxury fashion brand dummy and a set of control variables. The regression results indicate that the agency costs of the firms with luxury fashion brand exceed those of control group in the fashion industry in the part of operating expenses, but the agency cost falls short of those of control group in the part of EBITD, thus the aggregate agency costs are not differential of those of the control group. In sensitivity test, the results are same that the agency cost of the firms are higher than those of the matching control group with PSM(propensity matching method). These results are corroborated by an additional analysis comparing the group of the companies with the best brands with the control group. The results raise doubts about the effectiveness of management of the firms with luxury fashion brand. This study has a limitation that the research has performed only for 2013 and this paper suggests that there is room for improvement in the current research methodology.

• Journal of the Korean Society of Safety
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• v.20 no.1 s.69
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• pp.113-118
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• 2005

This study delivers the actual condition of investment for industrial accident prevention based on survey of 500 construction sites from 'reports far industry safety and health' published by Korea Occupational Safety & Health Agency (KOSHA). The various research techniques were used such as technical statistic analysis for construction industry, cost comparison of industrial accident prevention and accident loss. A formula was deduced to calculate accident loss and accident frequency by accident prevention cost through regression analysis.

• Journal of Industrial Convergence
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• v.20 no.8
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• pp.33-40
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• 2022

In this study, we tried to suggest a plan to improve the efficiency of operation after analyzing the actual conditions by selecting case areas operated by the cadastral resurvey responsible agency system. The research results are as follows. In the evaluation of the selection of a cadastral resurvey agency, a method to raise the qualitative evaluation score was suggested. The expansion of support for the cadastral resurvey agency made it possible to automatically connect and install when the LandyGo program is updated, and suggested that prior training should be stipulated in the related regulations. In the performance of cadastral resurvey surveying and division of duties, the installation of temporary boundary monuments and determine boundary monuments should be integrated. And this suggested the direction of conserving the project cost of the cadastral resurvey agency through joint implementation. Also, in the short-term and long-term perspectives, a plan for realization of project cost distribution in connection with the expansion of the entrustment of the cadastral resurvey responsible agency was presented. If the responsible agency system is operated by reflecting the results of this research, it is expected to improve the satisfaction of the project participants and shorten the project period.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 1998.03a
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• pp.169-176
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• 1998

This article investigates the software acquisition problems as two dimensional : custom/pacakage and insource /outsource. The analysis adopts the cost-benefit frame work in explaining software acquisition problems and takes two leveled approach. The first level examines the cost-benefit relationship of the determinants affecting both dimensions, and these determinants are derived from theories of transaction cost, incomplete contracting, and agency. The second level focuses on the impact of general cost-benefit frivers of the software acquisition decisions. The results facilitate a broader and more detailed understanding on the software acquisition problems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.184-190
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• 2020

In this study, two analyses were conducted in relation to the defense procurement agency. The first was a questionnaire survey conducted by defense business personnel to quantitatively measure the effectiveness of the defense procurement agency's utilization. In the second, the appropriate standard for brokerage fees was developed, the actual work of the defense procurement agency in overseas sales was surveyed, and the brokerage profit of the general product was applied to the defense procurement agency's brokerage profit data. Using the defense procurement agency was 1.07 times more effective than not using it, and the appropriate brokerage fee varied according to the project size. For medium / small projects, 5.1 ~ 8.7% of the total project cost is an appropriate brokerage fee, compared to 1.2 ~ 1.8% for big-scale projects. The government's appropriate brokerage fee is not fixed, but is elastically applied according to the size of the total project cost, and it is appropriate to analyze the characteristics of the project and identify and adjust the required activity cost in advance.

• Proceedings of the Korean Information Science Society Conference
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• 2008.06c
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• pp.539-544
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• 2008

이 논문에서 크기의 변화에 강인한 인공물 축출 알고리듬을 제안한다. 인공물은 크기 및 카메라 센서의 특성에 따라 영상에 다양한 크기로 나타난다. 이 논문은 이러한 크기 변화에 강인한 인공물 축출 방법을 제안한다. 우선 LoG(Laplacian of Gaussian)를 이용하여 최적의 크기를 찾아낸다. 이를 이용하여 우리는 이웃한 정보를 포함할 수 있는 MAP-MRF(Maximum A Posterior-Markov Random Field) 레이블링(Labeling) 방법을 기반으로 인공물 축출을 위한 비용함수를 제안하였다. 인공물은 서로 근처에 존재하기 때문이다. 여기서 정보 비용함수(Data cost function)는 방향 히스토그램(Orientation histogram)을 이용하여 정의하였고, 스무딩 비용함수(Smoothing cost function)는 ICM(Iterated Conditional Modes)을 이용하여 정의한다. 최종적으로 이 알고리듬을 위성영상에 적용하여 알고리듬의 성능을 증명한다.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2215-2217
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• 1999

The high current pulsed power systems(PPS) for rail guns, ET and ETC accelerators require many components of very high cost. If one failed to select component specifications based on optimal design, cost effective and reliable PPS could not be obtained. It is very significant to study a preliminary circuit scheme and to determine optimal specifications via circuit simulation before constructing the PPS based on modulized capacitor banks. The optimal crowbar resistor value, module inductance was determined in view of energy loss, the voltage reversal of capacitors and the transient current of crowbar diodes.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.7
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• pp.610-617
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• 2017

In the recent weapon system trend, it is required to develop small and low cost guidance missile to track and strike the enemy target effectively. Controling the such small drone typed weapon demands a integrated electronic device that equipped with not only a wireless network interface, a high resolution camera, various sensors for target tracking, and position and attitude control but also a high performance processor that integrates and processes those sensor outputs in real-time. In this paper, we propose the android smartphone as a solution for that and implement the guidance and control application of the missile. Furthermore, the performance of the implemented guidance and control application is analyzed through the simulation.

• Journal of the Korean Society of Safety
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• v.35 no.1
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• pp.34-44
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• 2020

The purpose of this study is to suggest ways to improve the transparency of occupational safety and health management cost (OSHMC) in order to create a safe working environment that can guarantee the health of construction workers. It was performed in the following procedures and methods. (1) collecting and analyzing resources related to the OSHMC in construction, (2) gathering stakeholder opinions for interviewing actual conditions, (3) deriving the improvement plans based on survey results and (4) suggesting direction for improvement of related laws based on the results of the research. As a result of this study, the following ways were found to be effective for enhancing transparency of the OSHMC in construction. (1) disclosure of usage details in sites, (2) Expansion of the standard for the OSHMC in construction, (3) Increase in fines for false use, (4) Establishment of the plan to improve the OSHMC ratio of small-scale construction sites, (5) Strengthen the role of supervisory and support organizations such as the Ministry of Employment and Labor and the Korea Occupational Safety & Health Agency. The result of this study is expected to be used as a basic data for future improvement of the occupational safety and health acts in Korea.