• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.826-831
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• 2001

Electromagnetic forces generate vibrations in the end-winding of large generators. A finite element analysis using a commercial S/W is performed to calculate electromagnetic force of end-winding in two pole generator for 500 MW fossil power plant. Also, this paper presents analytical and experimental modal analysis results of generator end- winding. Using validated FE model, 3D electromagnetic model which computes the forces on the end-winding is coupled with a 3D mechanical model which calculates the dynamic displacement and stress under electromagnetic forces. These results will be used to evaluate reliability of end-winding and applied to update model.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.1032-1039
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• 2001

In this paper, modal analysis of wind-power generator rotor system was performed by using finite element method. Experimental modal analysis of generator rotor system was performed and the result were compared with analytical ones. Sensitivity method and localized modification method were used to update finite element model. As a result of updating finite element model, errors of natural freguency were reduced within 0.5％ and MAC value was improved near by l. Stability characteristics of wind-power generator rotor-bearing system through harmonic analysis about several external force will be analyzed using finite element model.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2020년도 추계학술대회
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• pp.234-236
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• 2020

Content-adaptive training and transmission of the model parameters of neural networks can boost up the SR performance with higher restoration fidelity. In this case, efficient transmission of neural network parameters are essentially needed. Thus, we propose a novel method of compressing the network model parameters based on the training of network model parameters in the sense that the residues of filter parameters and content loss are jointly minimized. So, the residues of filter parameters are only transmitted to receiver sides for different temporal portions of video under consideration. This is advantage for image restoration applications with receivers (user terminals) of low complexity. In this case, the user terminals are assumed to have a limited computation and storage resource.

• Structural Engineering and Mechanics
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• 제32권5호
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• pp.667-683
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• 2009

FE model-based dynamic analysis has been widely used to predict the dynamic characteristics of civil structures. In a physical point of view, an FE model is unavoidably different from the actual structure as being formulated based on extremely idealized engineering drawings and design data. The conventional model updating methods such as direct method and sensitivity-based parameter estimation are not flexible for model updating of complex and large structures. Thus, it is needed to develop a model updating method applicable to complex structures without restriction. The main objective of this paper is to present the model updating method based on the hybrid genetic algorithm (HGA) by combining the genetic algorithm as global optimization method and modified Nelder-Mead's Simplex method as local optimization method. This FE model updating method using HGA does not need the derivation of derivative function related to parameters and without application of complicated inverse analysis methods. In order to allow its application on diversified and complex structures, a commercial FEA tool is adopted to exploit previously developed element library and analysis algorithms. Moreover, an output-level objective function making use of measurement and analytical results is also presented to update simultaneously the stiffness and mass of the analysis model. The numerical examples demonstrated that the proposed method based on HGA is effective for the updating of the FE model of bridge structures.

• 제어로봇시스템학회논문지
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• 제6권3호
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• pp.241-247
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• 2000

The reference model of an MRC (model reference control) provides the desired trajectory a plant should follow and thus the design of a reference model has a significant effect on control performance. In most control systems control input to a plant has some bounds and it is preferable to make use of as large control inputs as possible within the range of no saturation. In this paper a new approach of selecting the reference model is proposed for bounded control inputs. Design variables of the reference model are determined in such a way that maximizes the performance index within the range of no saturation. Moreover this variable reference model is regularly updated during control. This scheme is verified by application to the servo motor position control system in various simulations. The responses of the MRC with a variable reference model show better tracking performance than that with a fixed reference mode. Moreover by adjusting the update interval of the reference model the control performance can be further improved.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2003년도 추계 학술발표회 요지
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• pp.152-153
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• 2003

• 전기의세계
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• 제31권2호
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• pp.119-125
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• 1982

A new approach to the maneuvering target tracking problem is proposed. Its basic concept is to take the maneuver variable from the measurements. Tracking scheme based on the Kalman filter estimates the maneuver varieble from the residual and uses the estimates to update the Kalman filter. The estimation process is independent of target types and a model of the maneuver characteristics. All the filtering algorithms are processed in polor coordinate. Simulation results are presented and compared to that of the extended Kalman filter.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.427-430
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• 1989

For on-line ARMA spectral estimation, the fast transversal filter algorithm of extended least squares method(ETS FTF) is presented. The projection operator, a key tool for geometric approach, is used in the derivation of the algorithm. ELS FTF is a fast time update recursion which is based on the fact that the correlation matrix of ARMA model satisfies the shift invariance property in each block, and thus it takes 10N+31 MADPR.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.377-377
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• 2000

Current software cost estimation models, such as the 1951 COCOMO, its 1987 Ada COCOMO update, is composed of nonlinear models, such as product attributes, computer attributes, personnel attributes, project attributes, effort-multiplier cost drivers, and have been experiencing increasing difficulties in estimating the costs of software developed to new lift cycle processes and capabilities. The COCOMO II is developed fur new forms against the current software cost estimation models. This paper provides a case-based analysis result of the cost driver in the software cost models, such as COCOMO and COCOMO 2.0 by fuzzy and neural network.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2000년도 봄 학술발표논문집 Vol.27 No.1 (A)
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• pp.116-118
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• 2000

분산 공유 메모리(Distributed Shared Memory)시스템은 사용자에게 간단한 공유메모리 개념을 제공하기 때문에 사용자는 노드 사이의 데이터 이동에 관여할 필요가 없다. DSM에서 일치서 유지를 위한 프로토콜을 선택하는 것은 통신부하를 줄이는데 중요한 역할을 한다. 본 논문은 DSM 프로토콜을 효과적으로 선택하기 위한 새로운 성능평가 모델을 제시한다. 본 연구에서 제안하는 성능평가 모델을 사용함으로써 무효화방식(invalidate protocol), 갱신 방식(update protocol) 그리고 이주방식(migratory protocol)의 성능예측이 가능하다. 본 성능평가모델은 노드들 사이의 데이터 일치성(consistency)유지를 위한 부담을 최소화하는 최적의 DSM 프로토콜을 결정하는데 사용된다.