• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.14-15
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• 2009

Insulated Gate Bipolar Transistor(IGBTs) are widely used in power device industry. However, to improve the breakdown voltage, IGBTs are suffered from increasing on-state voltage drop due to structural design. In this paper, the new structure is proposed to solve this problem. The proposed structure has double p-floating layer inserted in n-drift layer. The p-floating layers improve the breakdown voltage compared to conventional IGBT without change of other electrical characteristics such as on-state voltage drop and threshold voltage. this is because the p-floating layers expand electric field distribution at blocking state. A electrical characteristic of proposed structure is analyzed by using simulators such as TSUPREM and MEDICI. As a result, on-state voltage drop and threshold voltage are same to a conventional TIGBT, but breakdown voltage is improved to 16%.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.89-92
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• 2001

Silent gas discharge method has been widely applied for ozone production, ultraviolet light and UV laser generation. Since ozone and ultraviolet applications have tendency to spread widely in industry, the development of efficient and low-cost power supply for such systems is a task of great impotency. This paper introduces high-frequency inverter type mode power supply designed for ozone generation tube and ultraviolet generation excimer lamp and considerations on this inverter and pulse density modulation control strategy applied in it.

• Knowledge Management Research
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• v.14 no.1
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• pp.95-119
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• 2013

Although merger and acquisition (M&A) has been considered as an important means to improve firm performance, most prior empirical research have failed to prove the relationship between M&A and firm performance. In order to fill this gap, this study attempts to identify the effect of M&A on firm performance based on knowledge resources relatedness and complementarity theory. For this purpose, this study examines complementarity patterns of knowledge resources and their impacts on acquirer's performance using M&A announcements of electronic commerce industry from 2001 to 2007. The results of this study indicate complementarity among knowledge resources are positively related with acquirer's market value. This study contributes to expand knowledge management research by identifying the relationship among knowledge resources and their impacts on firm performance.

• Transactions on Electrical and Electronic Materials
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• v.15 no.4
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• pp.201-206
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• 2014

LED lighting,considered to be a new growth industry, has attracted a great deal of attention due to its higher illumination and longer life time than existing light sources. In this study, high-efficiency and long-life LED fog lamps for automobiles were developed, which can substitute the existing 27 W halogen fog lamps for a used car market. For this purpose, the number of LED modules, the body, heat sink, and the output of the fog lamp were first optimized through a numerical analysis. Then, a 10 W-class LED fog lamp was prototyped based on the optimized numerical model, and the performance of the fog lamp was successfully verified through the experiments.

• Transactions on Electrical and Electronic Materials
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• v.14 no.4
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• pp.172-176
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• 2013

Microelectromechanical system switches are becoming more and more popular in the electronics industry; there is a need for careful selection of the materials in the design and fabrication of switches for reliability and performance issues. The membrane used for actuation to change the state of an RF switch is made mostly using gold or aluminum. Various designs of membranes have been proposed. Due to the flexure-type structures, the design complexity increases, which makes stress analysis mandatory to validate the reliability and performance of a switch. In this paper, the effective stress and actuation voltage required for different types of fixed-fixed membranes is analyzed using finite element modeling. Effective measures are presented to reduce the stress and voltage.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.6
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• pp.538-543
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• 2008

Nanostructured materials are attracting increased interest and application. Exciting perspectives may be offered by electrical insulation. Epoxy/Organoclay nanocomposites may find new and upgraded applications in the electrical industry, replacing conventional insulation to provide improved performances in electric power apparatus, e.g, high voltage motor/generator stator winding insulation, dry mold transformer, etc. In the paper work, the electrical and thermal properties of epoxy/organoclay nanocomposites materials were studied. The electrical insulation characteristics were analyzed through the permittivity characteristics. by analyzing the permittivity spectra, it was found that dielectric constant becomes smaller with increase frequency and becomes larger with increase temperature. This indicates restriction of molecular motion and strong bonds at the epoxy/organoclay nanocomposites. The morphology of nanocomposites obtained was examined using TEM and X-ray diffraction. It has been shown that the presence of polar groups leads to an increased gallery distance and partial exfoliation. Nevertheless, full exfoliation of clay platelets has not been achieved.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.11
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• pp.686-689
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• 2014

Electrostatic discharge has been considered as a major reliability problem in the semiconductor industry. ESD reliability is an important issue for these products. Therefore, each I/O (Input/Output) PAD must be designed with a protection circuitry that creates a low impedance discharge path for ESD current. This paper presents a novel Lateral Insulated Gate Bipolar (LIGBT)-based ESD protection circuit with latch-up immunity and high robustness. The proposed circuit is fabricated by using 0.18 um BCD (bipolar-CMOS-DMOS) process. Also, TLP (transmission line pulse) I-V characteristic of proposed circuit is measured. In the result, the proposed ESD protection circuit has latch-up immunity and high robustness. These characteristics permit the proposed circuit to apply to power clamp circuit. Consequently, the proposed LIGBT-based ESD protection circuit with a latch-up immune characteristic can be applied to analog integrated circuits.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.2
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• pp.66-72
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• 2010

Recently a large number of electronic control devices are abruptly increasing in vehicles as the electronic industry advances. Also the number of wiring harnesses and complexity of wiring is proportionally increased to the devices. A newly developed connector named bridge connector is introduced in this study for the purpose of the wiring structure changes. A wiring structure among distributed control systems by using serial communication is proposed with the bridge connector in this paper. The bridge connector contains a auto-recovery fuse made by PTC thermistor material for the protection of the over-currents on local control devices. The auto-recovery function of the fuse is needed for the maintenance free system in the distributed controls. The PTC fuse characteristics organized in this study is tested and the results are showed in detail for the real application.

• Proceedings of the Technology Innovation Conference
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• 1997.07a
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• pp.160-171
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• 1997

This paper starts out by reviewing the literature that in different ways utilizes patent data as a output of R&D investment. The main focus, however, is an analysis of time-lag between R&D input and output. To achieve this research objective, the basic data associated with the R&D input(expenditure, researchers) and output(patent, utilities) for the past 15 years, from 1980 to 1994, in the areas of electrical-electronic, mechanical and chemical industries have been collected. And the raw output data were altered it to objective data using Laspeyres approach and analyzed using multiple regression analysis, especially stepwise regression analysis. The result of this study can be summarized as follows: a) The time-lag between R&D input and output is from 1 to 4 years. This result is equal to the research conclusion of the existing foreign studies. b) It was found that the time-lag of patents was longer than of utility models. c) It was showed that the time-lag of electrical-electronic, mechanical industry was longer than the chemical one.

• Journal of Korea Technology Innovation Society
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• v.1 no.1
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• pp.23-36
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• 1998

The 1995 Informatization Promotion Act was passed to advance the national quality of life and to develop national economy by promoting informatization, forming the ground of telecommunication industry, and realizing the advancement of telecommunication infrastructure. This article was written to review whether this act's purpose was being achieved by Korean government. Even if Korean informatization policy implemetation structure is strongly centralized around the Ministry of Information and Communication, Information policies are formulated and implemented among agencies. To explain this phenomenon, I suggested the following factors : (1) The Korean government's lack of informatization experiences, (2) The political abuse of information policy, (3) the conceptual rigidity on the structure of information superhighway, (4) the absence of the basic principles for electronic government, (5) the uniformed regional informatization.