• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
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• pp.43-46
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• 1995

Adaptive algorithms based on gradient adaptation have been extensively investigated and successfully jointed with active noise/vibration control applications. The Filtered-X LMS algorithm became one of the basic feedforward algorithms in such applications, but still is not fully understood. The error path model effect on the Filtered-X LMS algorithm has been under the investigation and some useful properties related stability has been discovered. We are interested in utilizing the fact that the model error caused by the way optimizing the error path model in a view point of convergence speed of Filtered-X LMS algorithm for pure tone noise suppression application without any performance loss at steady state.

• 한국지능시스템학회논문지
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• 제19권2호
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• pp.185-190
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• 2009

본 논문은 무선 센서 네트워크를 위한 패킷 손실을 포함하는 비선형 네트워크 제어 시스템의 관측기 기반 지능 제어기를 제시한다. 비선형 시스템의 지능 제어를 위해 Takagi-Sugeno (T-S) 퍼지 모델링 기법을 이용하고, 이를 통하여 비선형 네트워크 제어 시스템을 퍼지 모델로 표현한다. 퍼지 모델로 표현된 네트워크 제어 시스템에 대하여 퍼지 관측기를 설계하고, 관측기의 측정치와 실제 시스템의 상태변수 간의 오차를 안정화 시킬 수 있는 출력 궤환 제어기를 설계한다. 제안된 제어기를 포함한 폐루프 시스템의 안정도 조건을 선형 행렬 부등식으로 나타내고, 부등식을 이용하여 제어기의 이득값을 구한다. 모의실험을 통하여 제어기의 효용성을 평가한다.

• 전자공학회논문지SC
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• 제39권6호
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• pp.59-70
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• 2002

본 논문에서는 최적 효율과 고성능으로 동작하는 SynRM(Synchronous Reluctance Motor)을 위한 위치 및 속도 센서리스 벡터제어를 제시한다. 제시한 제어 방법은 고정자 전압과 전류의 자속 추정에 기초한다. 그리고 동손과 철손을 최소화하는 효율 최적화의 전류각 조건은 SynRM의 등가회로를 기초로 유도한다. 폐루프 위치 및 속도 제어의 연구결과는 최적화 제어의 입증하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.87.2-87.2
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• 2010

The steady and dynamic process model for an internal reforming molten carbonate fuel cell power plant is discussed in this paper. The dominant thermal and chemical dynamic processes are modeled for the stack module and balance-of-plant, including cathode gas preparation, heat recovery, heat loss (Each heat loss amount for the stack and MBOP is obtained from real plant data) and fuel processing. Based on dynamic model and control demand, PID controllers are designed in the whole system. By applying these controllers we can obtain temperature balance of stack and control system depending on changing steam to carbon ratio, air feed amount, and transient condition.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.1127-1136
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• 1993

A mathematical model has been developed for the simulation of static stability of agricultural tractors. The model was based on Reichmann's model but modified to improve its shortcomings for practical applications. Two examples of model simulation were presented and showed its usefulness in evaluating the control and stability loss boundaries.

• 드라이브 ㆍ 컨트롤
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• 제18권4호
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• pp.84-90
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• 2021

Viscosity of hydraulic oils decreases due to loss reduction and efficiency increase of fluid power systems. However, low viscosity is not always appropriate due to the induction of large leakage and small lubricity. Therefore, a detailed study on the optimum viscosity of hydraulic oils is necessary. In this study, based on the thermohydrodynamic lubrication theory, numerical simulation was conducted using the slipper model of swashplate-type axial piston pumps and motors. The viscosity grades' (VG) effects of oils on power losses are mainly discussed numerically in fluid film lubrication, including changes in temperature and viscosity. The simulation results reveal that the flow rate increases and the friction torque decreases as VG decreases. The film temperature and power loss were minimised for a specific oil with a VG. The minimum conditions regarding the temperature and loss were different and closed. Under various operating conditions, the film temperature and power loss were minimised, suggesting that an optimum hydraulic oil with a specific VG could be selected for given operating conditions of pressure and speed. Otherwise, a preferable operating condition must be established to determine a specific VG oil.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.786-791
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• 2005

This paper is concerned with the examination and evaluation concerning a tuning method of multivariable PID controllers based on partial model matching on frequency domain proposed by authors from practical view point. In this case, PID controller parameters are determined by minimizing the loss function defined by the difference between frequency response of ideal model transfer function and actual frequency response on several frequency points. The purpose of the paper is to examine and evaluate the performance of the method through actual experiments of MIMO liquid level experimental process control equipment.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2009년도 정기총회 및 추계학술대회 논문집
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• pp.252-255
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• 2009

This paper proposes a new loss minimization controller (LMC) for induction motor drive. The proposed LMC presents a strategy to minimize the total power losses of induction motor (IM), which is based on simplified equivalent circuit and simplified model of IM. The proposed controller using the field oriented control (FOC) method is to determine an optimal rotor flux for obtaining the minimum total power losses and higher efficiency. Simulation and experimental results are given to validate the effectiveness of the proposed method.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.444-449
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• 2001

There have been many accidents of passenger ships on the sea and they have caused a big loss of human lives. Maritime Safety Committee(MSC) of International Maritime Organization(IMO) made evacuation analysis of Ro-Ro passenger ships mandatory in order to save as many lives as possible at the time of accident. But this is a temporary regulation and HSC/IMO ties to introduce a performance-based regulation to improve the effect of regulation. Simulation-based evacuation analysis is the basis of performance-based regulation. In this paper, we performed a simulation-based evacuation analysis on a passenger ship, which is usually used in the plying between land and islands in Korea, with EXODUS system. Through inspecting the results from this analysis in more detail, we can make a proposal to improve the safety of passenger ship. Finally we describe the features of IMEX(Intelligent Model for Extrication Simulation), a new evacuation model being developed in KRISO.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 제3회 압연심포지엄 논문집 압연기술의 미래개척 (Exploitation of Future Rolling Technologies)
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• pp.438-446
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• 1999

Crop minimization of the top and bottom ends of hot rolled plate, in a plate, in a plate mill, has been investigated. The existing model to determine the edging pattern at the finishing rolling pass was not reasonable to get high width accuracy and rolling yields. New models including width prediction have been formulated by using neural network model of back propagation learning algorithm and statistical analysis based on the actual production rolling data to give the optimal pattern for minimizing trimming loss. Using these models, at a given rolling condition of broadside pass and finishing pass and the permissible condition of width variation, it was possible to minimize crip at the top and bottom ends according to optimum procedure in plate mill. An application to improve the plan view pattern reduced width variation by 23% and crop length by 30% on average with an effective fishtail crop shape.