• KIEE International Transactions on Power Engineering
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• 제3A권4호
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• pp.181-190
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• 2003

This paper presents the design of a fuzzy power system stabilizer (FPSS) using an adaptive evolutionary algorithm (AEA). AEA consists of genetic algorithm (GA) for a global search capability and evolution strategy (ES) for a local search in an adaptive manner when the present generation evolves into the next generation. AEA is used to optimize the membership functions and scaling factors of the FPSS. To evaluate the usefulness of the FPSS, we applied it to a single-machine infinite bus system (SIBS) and a power system simulator at the Korea Electrotechnology Research Institute. The FPSS displays better control performance than the conventional power system stabilizer (CPSS) for a three-phase fault in heavy load, which is used when tuning FPSS. To show the robustness of the FPSS, it is applied with disturbances such as change of mechanical torque and three-phase fault in nominal and heavy load, etc. The FPSS also demonstrates better robustness than the CPSS. Experimental results indicate that the FPSS has good system damping under various disturbances such as one-line to ground faults, line parameter changes, transformer tap changes, etc.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.134-136
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• 2001

This paper describes the application of Fuzzy Power System Stabilizer(FPSS) for improving dynamic stability of power system. The Real-coding Genetic Algorithm(RGA) was applied to optimize gains of the inputs and outputs of the FPSS. The effectiveness of the proposed FPSS was demonstrated by simulation studies for single-machine infinite system. To show the superiority of the proposed FPSS, its performances were compared with those of Conventional Power System Stabilizer(CPSS) The proposed FPSS showed better control performances than the CPSS in three-phase ground fault under a normal load which was system condition in tuning FPSS. To show the robustness of the proposed FPSS, it was applied to damp the low frequency oscillations caused by disturbances such as three-phase ground fault under heavy and light load conditions. The proposed FPSS showed better performance than CPSS in terms of the settling time and damping effect for power system operation condition.

• 대한전기학회논문지:전력기술부문A
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• 제48권6호
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• pp.704-711
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• 1999

This paper presents a design of fuzzy power system stabilizer (FPSS) using adaptive evolutionary computation (AEC). We have proposed an adaptive evolutionary algorithm which uses a genetic algorithm (GA) and an evolution strategy (ES) in an adaptive manner in order to take merits of two different evolutionary computations. FPSS shows better control performances than conventional power system stabilizer (CPSS) in three-phase fault with heavy load which is used when tuning FPSS. To show the robustness of the proposed FPSS, it is appliedto damp the low frequency oscillations caused by disturbances such as three-phase fault with normal and light load, the angle deviation of generator with normal and light load and the angle deviation of generator with heavy load. Proposed FPSS shows better robustness than CPSS.

• Nuclear Engineering and Technology
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• 제51권3호
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• pp.908-914
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• 2019

Fusion power shutdown system (FPSS) is a safety system to stop plasma in case of accidents or incidents. The gas injection system for the FPSS presented in this work is designed to research the flow development in a closed system. As the efficiency of the system is a crucial property, plenty of experiments are executed to get optimum parameters. In this system, the flow is driven by the pressure difference between a gas storage tank and a vacuum vessel with a source pressure. The idea is based on a constant volume system without extra source gases to guarantee rapid response and high throughput. Among them, valves and gas species are studied because their properties could influence the velocity of the fluid field. Then source pressures and volumes are emphasized to investigate the volume flow rate of the injection. The source pressure has a considerable effect on the injected volume. From the data, proper parameters are extracted to achieve the best performance of the FPSS. Finally, experimental results are used as a quantitative benchmark for simulations which can add our understanding of the inner gas flow in the pipeline. In generally, there is a good consistency and the obtained correlations will be applied in further study and design for the FPSS.

• 한국통신학회논문지
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• 제21권5호
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• pp.1123-1131
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• 1996

Knutsson이 QPS(quadrature polar separable) 필터를 제안한 이후 여러가지 개선된 QPS필터가 발표되고 있으며 질감 영상처리에 응용되고 있다. 이들 필터는 방향각 함수로 Kuntsson의 cosine 함수나 지수감쇠 함수를 이용하고 있으며, 라디엘웨이팅 함수로 FPSS(finite prolate spheroidal sequence)나 점근적 FPSS를 이용하고 있다. 이들 필터는 질감영상 생성이나 방향각평가, 그리고 합성된 질감영상의 영역분할면에서 다른 특성을 나타낸다. 본 논문에서는 2-D QPS 필터를 위한 여러가지 커넬함수를 분석하여 그들의 특성을 고찰하며 푸리에영역내에서 국부조직의 주파수성분과 방향각을 평가한다. 그리고 이들 필터에 의한 질감 영상의 특성추출과 영역분할에 대한 응용상의 문제점에 대해서 고찰한다. 실험결과는 개선된 Knutsson 필터와 점근적 FPSS 필터함수가 합성 질감영샹의 방향각 평가와 영역분할면에서 유용하다는 것을 나타낸다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.206-208
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• 1997

This paper presents a design of self_tuning fuzzy logic controller using Genetic Algorithms for power system stabilization. FPSS(Fuzzy Logic Power System Stabilized is applied to the KERI(Korea Electric Research Int.) power system simulator so that its efficiency can be investigated in real time control. Genetic Algorithms are used to determine fuzzy membership functions. Experiment results show the better performances with FPSS in comparison to no PSS.

• 광학세계
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• 제13권2호통권72호
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• pp.45-48
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• 2001

향후 DPSS레이저 기술은 FPSS 레이저와 같은 수 키로와트 급 고출력 레이저의 실용화에 집중되고 있다. 키로 와트급 DPSS 레이저가 보편화 될 경우 현재 비반도체 레이저 시장에서 가장 큰 부분을 차지하고 있는 재료 가공용 고출력 레이저 시장의 대부분이 DPSS레이저로 대체되어 시장 규모가 엄청나게 증가할 것이다.

• 대한산업공학회지
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• 제22권2호
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• pp.277-302
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• 1996

The overall performance of BISDN depends significantly on the interconnection network or the switch fabric. Hence, it is extremely important to evaluate the performance of the network or the fabric. The well developed performance models also provide insight into the factors that determine design tradeoffs as well as quantitative estimates of their importance. The objective of this paper is to investigate and critically compare all the developed performance analysis models of FPS according to internal switch fabric structure, traffic assumptions, performance measures, methodologies, etc. FPSs are described according to their internal fabric structure. Brief history of FPS performance analysis is mentioned and performance analysis modeling is discussed.

• 한국음향학회지
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• 제12권4호
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• pp.5-13
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• 1993

본 연구에서는 조직 이미지 프로세싱에서 로칼 조직의 주파수 성분과 방향각을 효과적으로 평가할 수 있는 점근적 2-D FPSS QPS 필터의 커널쌍 구성에 대하여 논의하고 이를 아용한 오리엔테이션 필터의 설계와 응용을 고찰한다. 설계된 필터 특성은 필터 길이가 주어지는 경우 대역폭, 감쇄 정수, 방향각, 그리고 변이 정수에 의존하므로 특성 제어가 용이하다. 4개의 커널쌍으로 구성된 오리엔테이션 필터에 의한 방향각 측정 오차는 최대 2.5°이며 세그멘테이션 결과도 효과적임을 보였다. 그리고 단일 방향각을 갖는 오리엔테이션 필터에 의해 조직 이미지의 특성 성분의 추출이 용이함을 보였다.

• Molecules and Cells
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• 제19권2호
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• pp.294-299
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• 2005

A cDNA encoding farnesyl diphosphate synthase (FPS; EC2.5.1.1/EC2.5.1.10) was isolated from Centella asiacita (L.) Urban, using degenerate primers based on two highly conserved domains. A full-length cDNA clone was subsequently isolated by rapid amplification of cDNA ends (RACE) PCR. The sequence of the CaFPS (C. asiatica farnesyl diphosphate synthase) cDNA contains an open reading frame of 1029 nucleotides encoding 343 amino acids with a molecular mass of 39.6 kDa. The deduced CaFPS amino acid sequence exhibits 84, 79, and 72%, identity to the FPSs of Artemisia annua, Arabidopsis thaliana, and Oryza sativa, respectively. Southern blot analysis suggested that the C. asiatica genome contains only one FPS gene. An artificially expressed soluble form of the CaFPS was identified by SDS-PAGE. It had high specific activity and produced farnesyl diphosphate as the major isoprenoid.