• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2001년도 춘계학술발표대회 논문집
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• pp.133-139
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• 2001

Today the social concern about Interior Design gradually requires wide comprehension. Also according to demanders' requirement. Universities cope with speed. Interior Design made by experts for the function and purpose in the conception of decoration. Therefore, Universities we responsible to educate for more capable professional designers. But management is the first concern for Interior Design Company students are going to work at. Interior Design has not the important state yet in Korea, it is hard to manage the company with design alone. As architecture must get admittion, design is apart from construction. but they are worked together in Interior Design. It is true that all the work of construction is Capenters' or technical engineers' work except space design. Of course students are interested in just design not in construction. Students majoring in design need wide understanding of construction not a concept design. but detailed design for construction and proper valuation ability to manage company. I propose component and practical use of nude construction department to understand detailed design.

• Structural Engineering and Mechanics
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• 제17권5호
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• pp.707-725
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• 2004

An optimal design method with nonlinear elastic analysis is presented. The proposed nonlinear elastic method overcomes the drawback of the conventional LRFD method that accounts for nonlinear effect by using the moment amplification factors of $B_1$ and $B_2$. The genetic algorithm used is a procedure based on Darwinian notions of survival of the fittest, where selection, crossover, and mutation operators are employed to look for high performance ones among sections in the database. They are satisfied with the constraint functions and give the lightest weight to the structure. The objective function taken is the total weight of the steel structure and the constraint functions are strength, serviceability, and ductility requirement. Case studies of a planar portal frame, a space two-story frame, and a three-dimensional steel arch bridge are presented.

• 한국추진공학회지
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• 제5권4호
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• pp.40-49
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• 2001

우주발사체의 아포지 킥 모타에 대한 기초연구를 수행하였다. AKM은 3단형 과학로켓 KSR-III의 3단으로서 개발되었다. 이 고체 모타는 HTPB 계열의 복합제 추진제, 복합재 모타 케이스와 잠입형 노즐을 갖추었다. 고체모타를 체계요구조건에 맞도록 개발하기 위하여 우선 직경 520mm의 완성형을 설계하고 약 60% 크기의 축소형 모타를 먼저 개발, 시험하였다. 축소형 모타의 개발 시험으로 완성형 모타의 개발 타당성을 입증하였다. 2차에 걸친 완성형 지상연소 시험을 수행하였다.

• 반도체디스플레이기술학회지
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• 제14권3호
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• pp.57-60
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• 2015

Electric power in large devices is controlled by digital circuits, such as switching mode power supply. This kind of power circuits require accurate current sensor for power distribution. We studied characteristics of shunt resistor, which has many advantages for commercial application compared to Hall-effect current sensor. We applied ceramic package to the shunt resistor. Ceramic package has good thermal conductivity compared to plastic package, and this point is important for space requirement in Printed Circuit Board (PCB). Another advantage of the ceramic package is that surface mount technology (SMT) can be used for production. Our experimental results showed that the ceramic packaged resistor showed about 50% lower temperature than the plastic packaged one. Burning point and frequency characteristics are also discussed.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.753-762
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• 2004

Conceptual studies of a combined-cycle engine have been conducted. Herein, the results are presented. The engine is composed of ejector-jet, ramjet, scramjet and rocket modes, and will be mounted on the Single-Stage-to-Orbit aerospace plane. Propellants are hydrogen and oxygen. Calculated engine thrust performances and cooling requirement of the engine are presented. Pitching moment of the plane with the engine will be balanced even in the vacuum condition. The experimental results of the inlet and the ejector-jet, ramjet and scramjet modes are presented. The effect of the airframe configuration on the engine performance and the thermal environment in the in-side of the plane are also presented. Through the investigations, possibilities of the combined-cycle engine and the aerospace plane are being made clear now.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.434-439
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• 2002

The researches on the direct drive system, which directly transfers axle load of the traction motor to wheels, have been developed as a next generation drive system in Japan and Europe. As a result of excluding couplings and gear units, the direct drive system has advantages on the bogie mount space to be smaller sized, lower noisy, more efficient and less weighted than the conventional drive system - indirect drive system. Since the simplification of the direct drive system design depends on the design of the traction motors, the researches on the direct drive system with focusing on the traction motors get started. The advantages/disadvantages of direct drive system, types, structures, cooling systems and interfaces of the traction motors are presented on this paper. Furthermore, the development of other countries on the electric equipments of the next generation railway vehicles are discussed and the necessity ＆ requirement for developing new concepts of traction motors are assured.

• Journal of Communications and Networks
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• 제9권2호
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• pp.141-149
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• 2007

Multiple-input multiple-output (MIMO) transmit pre-coding/beamforming can significantly improve system spectral efficiency. However, several obstacles prevent precoding from wide deployment in early wireless networks: The significant feedback overhead, performance degradation due to feedback delay, and the large storage requirement at the mobile devices. In this paper, we propose a precoding method that addresses these issues. In this approach, only 3 or 6 bits feedback is needed to select a precoding matrix from a codebook. There are fifteen codebooks, each corresponding to a unique combination of antenna configuration (up to 4 antennas) and codebook size. Small codebooks are prestored and large codebooks are efficiently computed from the prestored codebook, modified Hochwald method and Householder reflection. Finally, the feedback delay is compensated by channel prediction. The scheme is validated by simulations and we have observed significant gains comparing to space-time coding and antenna selection. This solution was adopted as a part of the IEEE 802.16e specification in 2005.

• 대한산업공학회지
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• 제15권1호
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• pp.1-15
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• 1989

In the past few years, increasing numbers of automatic storage/retrieval system (AS/RS) using computer controlled storage/retrieval machine have been installed. This paper introduces two modeling approaches to determine the best operating policy for AS/RS : an M/G/1 queueing model and a computer simulation model. The operating policy consists of three elements. : the operation command cycle, the storage location method, and the operation dispatching rule. The analysis based on M/G/1 model is suitable for a quick and approximate evaluation, due to its inherent strict assumptions. The computer simulation can be used to perform a more realistic analysis. It is shown through the study that a significant improvement in the throughput and/or the space requirement can be expected by determining the best operating policy to a particular system. Most important, the computer simulation demonstrates its powerful capability in evaluating dynamic stochatic systems with imperfect information.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.985-987
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• 2003

This paper presents a design and characteristics analysis of a SRM drive for EPS application. A rack mounted EPS system is considered in this paper. A conventional driving room space and mechanical structure are suggested in design stage. In the restricted design conditions, motor parameters are determined for sufficient torque and speed. For the smooth torque generation and simple circuit of power system, 12/8 motor drive is considered. With FEM and magnetic circuit analysis, designed motor is simulated to meet the requirement of specifications. Effectiveness of the suggested SRM drive for EPS application is verified by the manufactured prototype motor drive tests.

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2005년도 춘계 학술발표대회 논문집
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• pp.322-323
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• 2005

Currently, there are varieties of communication media options, such as E-mail, Instant Message, SMS and Computer discussion group. These genres keep expanding with the integration of computers and wireless technologies and even more it allows people to communicate at different time without travelling distances, However, it is mostly impossible the one communication media satisfies the same task demands under different situations. And online communication media can not reach the actual purpose of traditional communication in keeping the interpersonal relationship and richness of communication by sharing time and physical space. Therefore, we researched and examined on the current state of appropriateness communication style in different given situation as affected by requirement and its characteristics. With the result in research and survey, we suggested new communication style mediated by everyday thing through the case study.