• 제목/요약/키워드: minimization model

검색결과 565건 처리시간 0.031초

Queuing Analysis of Opportunistic in Network Selection for Secondary Users in Cognitive Radio Systems

  • Tuan, Le Ahn;Hong, Choong-Seon
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(D)
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    • pp.265-267
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    • 2012
  • This paper analyzes network selection issues of secondary users (SUs) in Cooperative Cognitive Radio Networks (CRNs) by utilizing Queuing Model. Coordinating with Handover Cost-Based Network selection, this paper also addresses an opportunity for the secondary users (SUs) to enhance QoS as well as economics efficiency. In this paper, network selection of SUs is the optimal association between Overall System Time Minimization Problem evaluation of Secondary Connection (SC) and Handover Cost-Based Network selection. This will be illustrated by simulation results.

Support Vector Machine을 이용한 지능형 신용평가시스템 개발 (Development of Intelligent Credit Rating System using Support Vector Machines)

  • 김경재
    • 한국정보통신학회논문지
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    • 제9권7호
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    • pp.1569-1574
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    • 2005
  • In this paper, I propose an intelligent credit rating system using a bankruptcy prediction model based on support vector machines (SVMs). SVMs are promising methods because they use a risk function consisting of the empirical error and a regularized term which is derived from the structural risk minimization principle. This study examines the feasibility of applying SVM in Predicting corporate bankruptcies by comparing it with other data mining techniques. In addition. this study presents architecture and prototype of intelligeht credit rating systems based on SVM models.

GPC를 이용한 자기동조 PID 제어기 (Self-tuning PID-controller based on GPC)

  • 유연운;김종만;이창구;김성중
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.188-193
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    • 1992
  • The PID controllers which is widely used in the process industry are poorly damped when the dynamic process contains significant dead time or when there are random disturbances acting on the plant. GPC is known to be more superior than conventional self-tuning algorithm in overcoming above problem and prior choice of model order. In this paper, we propose the method which determine the parameter of PID controller from minimization of GPC criterion. The controller has emplicit scheme which is comprised of parameter estimation and PID control design. Simulation results show the performance of the proposed self-tuning PID controller.

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유전 알고리즘을 이용한 단조공정중 중간 공정 최적설계 (Optimal Intermediate Process Design in Forging by Genetic Algorithm)

  • 정제숙;황상무
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1997년도 춘계학술대회논문집
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    • pp.155-158
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    • 1997
  • The investigation deals with of a intermediate process condition hving a bolt-shaped final product where it is required to extend tool-life in forging. In this study, optimization of the design variables is conducted by a genetic algorithm, where the fitness values are evaluated on the basis of FEM analysis model. The approach is applied to the determination of the intermediate process conditions which are optimal with regard to minimization of peak die pressure.

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SENSITIVITY ANALYSIS OF A SHAPE CONTROL PROBLEM FOR THE NAVIER-STOKES EQUATIONS

  • Kim, Hongchul
    • Korean Journal of Mathematics
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    • 제25권3호
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    • pp.405-435
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    • 2017
  • We deal with a sensitivity analysis of an optimal shape control problem for the stationary Navier-Stokes system. A two-dimensional channel flow of an incompressible, viscous fluid is examined to determine the shape of a bump on a part of the boundary that minimizes the viscous drag. By using the material derivative method and adjoint variables for a shape sensitivity analysis, we derive the shape gradient of the design functional for the model problem.

축소 반응 메카니즘으로부터 예혼합 화염 및 자발화 계산 (Premixed Flames and Auto-ignition Computations with the Short Chemical Mechanism)

  • 이수각;이기용
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2012년도 제44회 KOSCO SYMPOSIUM 초록집
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    • pp.279-281
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    • 2012
  • A short chemical mechanism was developed with the chemical model reduction strategy based on the use of Simulation Error Minimization Connectivity Method(SEM-CM). We examined the accuracy resulting from using this mechanism, as compared with the full mechanism, for premixed flames and auto-ignition of methane-air mixture under high pressures. These comparisons are in good agreement, but it has a little divergence to predict the ignition delay time at high pressure conditions as compared with experiment results.

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Hopfield Network을 이용한 작업영역 분할 (Division of Working Area using Hopfield Network)

  • 차영엽;최범식
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.160-160
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    • 2000
  • An optimization approach is used to solve the division problem of working area, and a cost function is defined to represent the constraints on the solution, which is then mapped onto the Hopfield neural network for minimization. Each neuron in the network represents a possible combination among many components. Division is achieved by initializing each neuron that represents a possible combination and then allowing the network settle down into a stable state. The network uses the initialized inputs and the compatibility measures among components in order to divide working area.

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다중 목적함수 최적화기법을 이용한 전기강판 생산 공정설계 (Process Design of Electric Steel by a Multiple Objective Optimization)

  • 정제숙;변상민;김홍준;황상부
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1997년도 추계학술대회논문집
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    • pp.153-157
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    • 1997
  • The investigation deals with the process design in cold rolling mill of electric plant. In this study, multiple objective optimization is conducted by a genetic algorithm, where the fitness values are evaluated on the basis of one - dimensional model of flat rolling. The approach is applied to the determination of the process conditions which are optimal with regard to minimization of roll power and maximization of productivity.

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전송 시스템에서 비선형 채널특성을 이용한 적응 등화기 알고리즘 (Adaptive Equalization Algorithms of Channel Nonlinearities in Data Transmission Systems.)

  • 안봉만;임규만
    • 융합신호처리학회 학술대회논문집
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    • 한국신호처리시스템학회 2003년도 하계학술대회 논문집
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    • pp.238-241
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    • 2003
  • This paper presents a nonlinear least squares decision feedback equalizer Bilinear systems are attractive because of the ability to approximate a large class of nonlinear systems efficiently. The nonlinearity of channel is modeled using a bilinear system. The algorithms are derived by using the QR decomposition for minimization covariance matrix of prediction error by applying Givens rotation to the bilinear model. Result of computer simulation experiments that compare the performance of the bilinear DFE to two other DFE's in eliminating the intersymbol interference caused by a nonlinear channel are presented In the paper.

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노이즈 모델에 기반한 훼손된 얼굴 영상의 인증 (Authenticating Corrupted Face Images Based on Noise Model)

  • 정호철;황본우;이성환
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2004년도 봄 학술발표논문집 Vol.31 No.1 (B)
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    • pp.805-807
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    • 2004
  • 본 논문에서는 노이즈 모델에 기반한 훼손된 얼굴 영상의 인증하는 방법을 제안한다. 제안된 방법은 먼저 학습 단계에서 노이즈 파라미터의 변화에 의해 훼손된 영상을 생성한다. 그 훼손된 영상과 노이즈 파라미터는 PCA에 의해 훼손된 영상과 노이즈 파라미터들의 선형 조합으로 표현된다. 테스트 단계에서는 훼손된 영상으로 LSM(Least-square minimization)방법을 적용하여 훼손된 영상의 노이즌 파라미터를 추정한다. 그리고 추정된 노이즈 파라미터를 가지고 원본 영상으로부터 합성된 영상을 생성하고, 그것을 테스트 영상과 인증한다. 실험 결과는 제안된 방법이 노이즈 파라미터를 정확하게 추정하여 얼굴 인증의 성능 개선 가능성을 보여준다.

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