• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.237-240
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• 2004

In this study, we have developed a new $UV(\lambda=355nm)$ laser micromachining technology by direct ablation method without masks. This technology allows that 3D micro parts can be fabricated rapidly and efficiently with a low price. And it has a benefit of reducing fabricating process simply. Due to micro parts' fabrication, such technologies need the control of XYZ stages with high precision, the design of optical devices to maintain micron spot sizes of laser beam and the control technology of laser focus. Also, we have fabricated a micro-channel through the developed laser micromachining technology and verified it through the results.

• Journal of Korean Society for Quality Management
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• v.35 no.3
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• pp.75-87
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• 2007

This paper deals with an integration model of three major quality management systems. The well known global standards such as ISO 9001 quality system, Malcolm Baldrige model, and EFQM model are integrated as a prototype quality system. The proposed model is then applied to help a power generation company to select improvement tasks for enhancing quality management. Here, we discuss three quality management systems, an integration process of the three systems, the integrated model, and a real world application case.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.34-37
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• 2005

While all-aluminum front end carriers have been frequently used by major foreign auto-makers, the carriers domestically produced are typically hybrid types. It is understood that higher fuel efficiency due to weight reduction can be achieved by using aluminum carriers because of aluminum's light weight. Moreover, aluminum is expected to posess high corrosion resistance and recyling rate. As a first step to enhance feasibility of domestic production of all-aluminum carriers, several carriers made by advanced auto makers are examined and compared. Besides basic characteristics such as appearance and weight, physical properties including composition, strength and elongation are carefully analyzed to obtain critical design and process factors.

• Transactions of Materials Processing
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• v.24 no.1
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• pp.13-19
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• 2015

For an accurate analysis of hot stamping, a coupled simulation with different aspects of the process(i.e. mechanical, thermal, and phase transformation) is needed. However, coupled simulations are time consuming and costly. Therefore, the current study proposes a simplified method focused on the forming for the hot stamping simulation of a coupled torsion beam axle (CTBA) tubular beam. In this simplified method, non-isothermal conditions were assumed and only conduction was considered, since it represents the majority of the heat transfer during hot stamping. In addition, temperature and strain rate effects were also included. Moreover, an isothermal simulation was conducted and compared with a non-isothermal simulation. Finally, the simulations were verified by experiments. In conclusion, the proposed method is shown to be effective for the development of tube-type parts, and it effectively predicts the deformation of the tubular beam during hot stamping.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.329-331
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• 2003

PROSET2000 that is integrated protective management system had developed and used in order to automate the setting process of protective relays in transmission system protection. PROSET2000 have database for relay setting and automated for relay setting program within. This paper proposed PCM current differential relay setting program point of Object Oriented Programming paradigm using Unified Modeling Language about additional relay in PROSET2000. Nevertheless each relay uses same current differential but setting method is different. This paper discribed different thing about setting method of each relay and evaluated more effective and corrective relay setting program using UML.

• Electronics and Telecommunications Trends
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• v.36 no.3
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• pp.23-33
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• 2021

Two main technologies of III-V/Si laser diode for optical communication, direct epitaxial growth, and wafer bonding were studied. Until now, the wafer bonding has been vigorously studied and seems promising for the ideal III-V/Si laser. However, the wafer bonding process is still complicated and has a limit of mass production. The development of a concise and innovative integration method for silicon photonics is urgent. In the future, the demand for high-speed data processing and energy saving, as well as ultra-high density integration, will increase. Therefore, the study for the hetero-junction, which is that the III-V compound semiconductor is directly grown on Si semiconductor can overcome the current limitations and may be the goal for the ideal III-V/Si laser diode.

• Journal of Korea Port Economic Association
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• v.38 no.2
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• pp.165-183
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• 2022

The main purpose of this paper is to present a competitive strategies for the Logistics Warehouses of Busan New Port. Based on the survey conducted by the Logistics Warehouses of Busan New Port experts, the categorized factors were compared using the analytic hierarchy process (AHP) to assess the importance of each factor and sub-factor in the case of the Logistics Warehouses of Busan New Port. This is a quantitative study that conducted a face-to-face survey on employees and related public officers at the Logistics Warehouses of Busan New Port. The final sample size consisted of 49 people, including workers at the Busan New Port logistics warehouses and related local customs officers. The data were coded in Microsoft Excel and the imprtance of SWOT factors was derived using "the I make it" program developed by Decision Sience, and it was analyzed using the AHP method. This study quantifies the importance of the strengths, weaknesses, opportunities, and threats factor of the Logistics Warehouses of Busan New Port and presents strategic guidelines for the key factors for the development of the Logistics Warehouses of Busan New Port. This research provides strategic guidelines to Korea for the development of the Logistics Industries, and development of the Logistics Warehouses of Busan New Port.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.05a
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• pp.187-190
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• 2007

The objective of this paper is to investigate into the development of injection mould with high cooling characteristics using a direct metal RP technology. In order to manufacture the injection mould with a high cooling rate, three-dimensional conformal cooling channels have been generated in the mould. DMT process, which is one of direct metal RP technologies, has been utilized to directly manufacture the metallic mould with three-dimensional conformal cooling channels. In order to examine the performance of the designed mould, injection molding tests have been carried out. The results of the experiments have been shown that a cooling time and the injection time of the proposed mould are reduced by the factor of five and two times in comparison with the injection mould with linear cooling channels.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.354-357
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• 2001

In the present study, front lower arm and engine cradle which are automotive chassis parts were developed using the hydroforming technology. For systematic establishment of parts development process, material properties of tube were reflected at the start of design and problems of initial design drawing were solved by forming analysis. Design and manufacturing technology of hydroforming die were established and the relationship between internal pressure and feeding stroke was studied during try-out. Durability and buckling strength of hydrofromed parts were estimated.

• Journal of Korean Institute of Industrial Engineers
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• v.36 no.2
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• pp.117-124
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• 2010

The military vehicles are an inevitable resource that is indispensible to successfully perform modern wars. Military vehicles used in the Korean Army are the copycats of American out-dated military vehicles, but limited to fulfill the specific requirements by the operators. Korean army are nowadays trying to launch a new developmental plan for military vehicles of new concepts by the Korean Army. This article, hence, extracts the necessary factors upon the advancement of military vehicles by the expertises with the operation of military vehicles as well as sufficient experiences about maintenance. Suggesting and setting up the priority, the result makes practical application for the decision of the development of military vehicles.