• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 추계종합학술대회 논문집
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• pp.825-828
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• 1999

In this paper, we design the analog phase shifter for the elimination of the ghost signal. Compensation of the delay between the reference signal and the relatively delayed signal is possible. This phase shifter uses the vector summing method. We use for the attenuator in our system FETs. The phase shifter is operated at the 200MHz and composed by lumped elements. The proposed analog phase shifter is simulated by the HP ADS software.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1919-1921
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• 2002

In this paper, we were designed the ferroelectric phase shifter using 3-dB, $90^{\circ}$ branch-line hybrid coupler with two ports terminated in symmetric phase-controllable reflective networks. The design of phase shifter is based on reflection theory of terminating circuits. In order to find the optimum conditions of reflect phase, the effect of a change of capacitance and transmission line connected with two coupled ports of a coupler have been investigated. To obtain more accurate design parameters, finite element method is applied. We were showed large phase variation with small capacitance variation in the parallel connection of capacitor and transmission line by using EM-simulation and circuit-simulation.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.212-215
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• 2008

건축공사의 공사비 절감은 시공단계보다 사업초기단계 및 설계단계에서 정확한 공사비 예측을 함으로써 더욱 효율적으로 절감될 수 있다. 하지만 현행 공공 건설공사의 공사비 산정 및 관리는 실시설계 이후로 집중되어 있어, 계산견적을 중심으로 실시되는 기획 및 기본설계단계에서의 사업비관리는 매우 취약하다고 볼 수 있다. 이에 본 연구에서는 현행 공사비 산정 방법의 문제점 및 실적공사비 사례정보 분석하여 기본설계단계에서 구체적 비용 계획을 세우고 이에 부합되는 설계가 진행되는지 검토 가능한 공사비 산정모델 개발을 위한 예비적 연구를 수행하였다.

• 디자인학연구
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• 제2권1호
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• pp.99-106
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• 1989

Environmental designers face a wide range of problems to be solved in their day-to-day works. The scale and number of problems and so enormous that designers should be a way out to meet these complex situation. Lately, environmental design process based on systems a.pproach is chosen for design methodology. It is a very complicated procedure with many alternatives. It is a evolutionary process that establishes the solution of a series of problems. This study attempt to tell the designer how to find design solution to problems and how to organize form as solution problems. The model of this design process is largely composed of three phases; Phase I : Problem definition and existing system analysis. Phase II : design goals and objectives, design criteria Phase III : creative process of design form.

• 한국건설관리학회논문집
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• 제21권6호
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• pp.103-112
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• 2020

본 연구에서는 실제 업무수행 사례를 바탕으로 친환경 관련 건설사업관리 업무관리방안을 주요 단계별로 도출하였다. 이에 따라 녹색건축인증을 중심으로 심의단계, 인/허가단계, 실시설계단계의 운영 및 관리 프로세스에 대한 건설사업관리 업무 세부 내용의 중요도를 분석하였다. 또한, 녹색건축인증 공사비 분석에 대한 선행 연구 사례를 통해 추가되는 공사비와 획득 점수 비중을 근거로 주요 항목을 도출하였으며, 녹색건축인증의 주요 항목에 대한 건설사업관리 업무 세부 내용의 중요도를 분석하였다. 그 결과, 심의단계에서는 행정적인 요구사항을 만족시키기 위해 녹색건축인증과 관련한 반영 요소의 확인, 인/허가단계에서는 설계도서 적정성, 각 단계별 설계의 연계성, 실시설계단계에서는 시공단계와 직접적으로 연관된 사항들에 대한 검토 및 확인이 중요한 것으로 나타났다. 그리고 녹색건축인증의 주요 항목에 대해서는 설계도서에 관련 기술의 철저한 반영, 적정성 검토 및 확인이 중요한 것으로 나타났다. 본 연구의 결과는 기존의 설계단계 건설사업관리자 업무(역할) 세부 내용을 토대로 녹색건축인증의 운영/관리 프로세스와 주요 항목의 측면에서 효율적인 관리방안으로 활용될 수 있을 것으로 기대한다.

• Journal of Electrical Engineering and Technology
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• 제10권3호
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• pp.1007-1014
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• 2015

An optimally designed six-phase induction motor (6PIM) is compared with an initial design induction motor having the same ratings. The Genetic Algorithm (GA) method is used for optimization and multi objective function is considered. Comparison of the optimum design with the initial design reveals that better performance can be obtained by a simple optimization method. Also in this paper each design of 6PIM, is simulated by MAXWELL_2D. The obtained simulation results are compared in order to find the most suitable solution for the specified application, considering the influence of each design upon the motor performance. Construction a 6PIM based on the information obtained from GA method has been done. Quality parameters of the designed motors, such as: efficiency, power losses and power factor measured and optimal design has been evaluated. Laboratory tests have proven the correctness of optimal design.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.25-27
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• 2012

The domestic construction industry recognize that review of design and construct-ability has the devastating effects. The way to take advantage of BIM for increase the possibility of discovered the design errors in advance are being discussed a lot recently. Since 2012, Public procurement published that the Turn-key project which is the more than 50 billion won in construction have to let the BIM-based design be mandatory. However, people expected the advent of BIM technology can resolve the existing design errors. But the situation is the connection of design stage and construction stage is very insufficient in domestic. Therefore, in this study understanding the types of design errors in construction phase. according the review of design errors before construction. Then can acceleration the application of BIM to improve the workability in a construction site.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 A
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• pp.94-97
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• 1998

The conceptual design of integrated three phase superconducting fault current limiter (SFCL) is presented. And through simulation of power system where this SFCL is installed, the characteristics of this SFCL is analyzed. It is like three-phase transformer. So it has the same characteristics with inductive single phase SFCL. But it has more merits than single phase SFCL. Differently to single phase SFCL, integrated three phase SFCL induces impedance at all phase by any single phase fault to protect the power system more safely.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 2부
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• pp.103-108
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• 2010

The purpose of this study is to analyze of the risk factors for oversea plants construction projects. For this study, risk factors data from related literature review, research organization and construction company was researched and classified under each EPC phases. In addition, a questionnaire survey by plant experts was conducted for analysis of risk weight and costs and time impact on each EPC phases. The results of this study are as follows: First, a detail design errors(engineering phase), a equipment procurement plan(procurement phase), and exchange rate fluctuations(construction phase) were analyzed the highest weight factors. Second, a financing plan(engineering phase), quantity take-off bill(procurement phase), and exchange rate fluctuations(construction phase) were analyzed the highest cost impact factors. Third, detail design errors(engineering phase), a equipment procurement plan(procurement phase), and schedule management errors(construction phase) were analyzed the highest time impact factors.

• 전기학회논문지
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• 제62권4호
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• pp.510-516
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• 2013

This paper suggests a 3-phase series-resonant type high voltage capacitor charger for an EML pulsed power system. The operating principle on the charger is explained by an equivalent circuit. Additionally, we analyze the charging characteristic in one discontinuous conduction mode and three continuous conduction modes. The analysis shows that the resonant current per phase is two thirds of the 3-phase charger's average charging current and one third of the single-phase charger's average charging current with the same capacity. We suggest a design method of the 3-phase capacitor charger in each operational mode and present an example of 3.5 kW capacitor charger at ${\omega}_s=0.33{\omega}_r$. The 3.5 kW 3-phase capacitor charger prototype is assembled with a TI28335 controller and a 40 kJ, 7 kV capacitor. The design rules based on the analysis are verified by experiment.