• 한국항해항만학회지
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• 제29권3호
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• pp.181-187
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• 2005

국내 최초로 운항예정인 수륙양용 아쿠아버스의 운항 리스크를 낮추고 안전을 확보하기 위하여 운항예정 해역인 월미도와 영종도간 수로에 대한 자연적환경과 해상교통량을 조사하고, 그들의 위험요소를 분석하였다. 그리고 아쿠아버스의 통항 안전 확보를 위하여 경계수역 지성, 잔용선착장 설치, 운항관리 방안 등을 제안하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.368-370
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• 2005

Due to the tendency towards large capacity and complexity of power system, an enhancement of power system equipment make a system impedance to be low in power system. Generally if an equivalent impedance of system becomes lower, a system stability will be better. But the fault current becomes very larger. The 345kV ultra-high voltage system will use current limit reactors(CLR) in a transmission line or a bus in substation to limit the magnitude of fault current. The CLR makes a significant contribution to the severity of the transient recovery voltage(TRV) experienced by feeder and bus circuit breakers on clearing feeder faults. Based on the conclusions of an investigation of actual circuit breaker failures while performing this duty, the mitigation of the transient recovery voltage associated with the reactors is described. Therefore in this article we simulated the TRV by EMTP at Bus Terminal Fault.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.593-598
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• 2007

대중 교통수단 중에서 아직도 많은 사람들이 버스를 이용한다. 그러나 버스 승객들이 사용하는 버스터미널의 대기공간은 점차 늘어나는 버스터미널 이용객들이 만족하는 서비스의 제공이 원활히 이루어지지 못 하는 현실이다. 이에 버스를 이용하기 위한 승객들의 대기 공간에서 나타나는 행태와 환경행태에 대한 조직적인 관찰을 통해서 기존장소에 대한 분석을 하였다. 그리하여 주어진 환경 안에서 얻을 수 있는 환경경험과 주어진 환경 내에서 발생되는 환경행태에 영향을 주는 요인들에 대한 정의를 내리고 이렇게 나온 자료(data)와 정보(information)를 근거로 하여 Redesign시 고려하여야 할 설계지침서(design guideline)를 제안하고자 한다.

• 한국정밀공학회지
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• 제10권4호
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• pp.227-235
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• 1993

In this paper, the development of a high performance flexible controller is described. The hardware of the controller, based on VME-bus, consists of four M68020 single-board computers (32-bit) with M68881 numerical coprocessors, two M68040 single board donputers, I/O devices (such as A/D and D/A converters, paraller I/O, encoder counters), and bus-to-bus adaptor. This software, written in C and based on X-window environment with Unix operating system, includes : text editor, compiler, downloader, and plotter running in a host computer for developing control program ; device drivers, scheduler, and mathemetical routines for the real time control purpose ; message passing, file server, source level debugger virtural terminal, etc. The hardware and software are structured so that the controller might have both flexibility and extensibility. In papallel to the controller, a three degrees of freedom kinematically redundant robot has been developed at the same time. The development of the same time. The development of the robot was undertaken in order to provide, on the one hand, a computationally intensive plant to which to apply the controller, and on the other hand a research tool in the field of kinematically redundant manipulator, which is, as such, an important area. By using the controller, dynamic control of the redundant manipulator was successfully experimented, showing the effectiveness and flexibility of the controller.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.669-671
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• 2004

This paper presents a MIMO nonlinear controller for the power system consisting of a turbine and a synchronous generator connected to an infinite bus. The controller proposed is based on feedback input-output linearization; its main goal is to regulate the terminal voltage and frequency, and is to improve the transient stability under large disturbances and unexpected faults. It is guaranteed that the voltage converges to its reference value exponentially, and that the frequency and the mechanical/electrical power are bounded. The design procedure is tested on a single machine infinite bus power system through simulations, and is seen to be effective.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.12-13
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• 2006

In this paper, RCF(Resistive Companion Form) analysis method which is used to analyze small signal stability problems of non-continuous systems including switching device. The RCF analysis method are applied to the power systems with the thyristor controled FACTS equipments such as TCSC. As a result of simulation, the RCF method is very powerful to calculate the oscillation modes exactly after the switching operations, and useful to analyze the small signal stability of power systems with switching devices such as FACTS equipments. As an applicable example of the RCF method in power system, the one machine infinite bus system including TCSC at generator terminal bus is investigated and the results proved that variations of oscillation modes after periodic switching operations of TCSC can be calculated exactly.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1060-1062
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• 1999

This paper proposes a guideline of choosing the optimum stabilizer input considering the gain margin of power system stabilizer between the optimum stabilizer gain and the allowable maximum stabilizer gain in accordance with the five inputs, such as generator shaft speed, bus frequency, electrical power, accelerating power and bus terminal voltage. The local mode damping and exciter mode damping are considered with increasing the stabilizer gain to determine each gain margin of the inputs.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.63-64
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• 2007

In this paper, an adaptive passivity based excitation and governor control scheme is proposed to enhance the transient stability of a single machine infinite bus power system with parametric uncertainties. We employ a state model where the frequency, the difference between active and mechanical power, and the difference between the squared terminal voltage and its reference are regarded as state variables. Using this state model, the proposed controller is obtained in two steps; firstly, a simple direct adaptive passivation controller is designed for the power system with parametric uncertainties; then a linear PI controller is applied to guarantee the stability of the closed loop system.

• 한국통신학회논문지
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• 제13권1호
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• pp.19-27
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• 1988

종합정보통신망(ISDN)의 실현을 위한 가입자-망 인터페이스에서, 효율적으로 위상배열된 시간 압출 다중화전송 시스템을 2선식 수동 버스상에서 설계하고 그 성능을 분석하였다. 시간압축다중화 전송시 인접채널에 의한 누화잡음과 원신호의 신호대잡음비(SNR)는 9.72(dB)이며 위상 배열과정에서 프레임의 최대 전송시간이 6(usec)이 되도록 설계하여 연결거리가 0.8Km까지 확장됨을 확인하여 제시한 전송시스템은 최종 가입자와 망의 접속에 적합함을 확인하였다.

• 한국환경보건학회지
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• 제25권3호
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• pp.51-57
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• 1999

This study was carried out to investigate the concentrations of Ni, Cr and Cu, to analyze the correlations among those, and between concentrations and traffic volumes by type of car in roadside ambient air at Chongro-, Chungkechon- and Kangnam terminal- area in Seoul from October 1st to October 31st in 1997. The results were as follows ; 1. The means of concentrations of Ni in roadside ambient air were 34.1, 25.1 and 23.6 ng/m$^3$ at Chungkechon, Kangnam terminal and Chongro area, respectively. The highest concentrations of Ni by time were 26.8 in the evening, 45.5 in the evening and 49.4 ng/m$^3$ in the forenoon at Chongro, Chungkechon and Kangnam terminal area, respectively. 2. The means of concentrations of Cr in road side ambient air were 97.7, 80.1 and 70.9 ng/m$^3$ at Chong, Chungkechon and Kangnam terminal area, respectively. The highest concentrations of Cu by time were 205.3 in the evening, 114.4 in the evening and 92.3 ng/m$^3$ in the forenoon at Chongro, Chungkechon and Kangnam terminal area, respectively. 4. The tendencies of concentrations of Ni and Cr by time were similar to each other. Especially, at Kangnam terminal area, correlation coefficients between concentrations of Ni and Cr and the traffic volume of bus were high(r=0.997,0.975). 5. The tendency of concentration of Cu and the traffic volume of passenger car at each area were high(r=0.832, 0.968) 6. Correlation coefficients between Cu and Zn, and between Ni and Cr were 0.762 and 0.842, respectively. This means that the possibility of co-existence of Cu-Zn or Ni-Cr is very high.