• Title/Summary/Keyword: combination approach

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A new computational approach to stability analysis of linguistic fuzzy control systems - Part l: Affine modeling of fuzzy system (컴퓨터 연산을 통한 언어형 퍼지 제어 시스템의 새로운 안정도 해석: 1부 - 퍼지 시스템의 어핀 모델링)

  • 김은태;박순형;박민용
    • Proceedings of the IEEK Conference
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    • 2001.06c
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    • pp.169-172
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    • 2001
  • In recent years, many studies regarding the modeling of fuzzy system have been conducted. In this paper, a new computational approach to modeling of linguistic fuzzy system is proposed The fuzzy system is modeled as a combination of affine systems, The proposed method can be used in a rigorous stability analysis of fuzzy system including the linguistic fuzzy controller.

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A study on the combined direct and indirect approach to adaptive system (적응제어에서 직접 및 간접 방식의 결합에 관한 연구)

  • 송호석;이기서
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.489-493
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    • 1989
  • In this paper a new approach to adaptive control using a combination of both direct and indirect methods has been proposed. Based on the estimates of the plant parameters and the current values of the control parameters, closed-loop estimation errors .epsilon.$_{\theta}$(t) and .epsilon.$_{k}$(t) are defined. These in turn are used in the adaptive laws for updating both identification as well as control parameters. The global uniform stability of the overall system is shown by constructing a Lyapunov function.n.

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The Application of Generalized Characteristic Coordinate System

  • Wu Z. N.;Chen Z.
    • 한국전산유체공학회:학술대회논문집
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    • 2003.10a
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    • pp.126-127
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    • 2003
  • In the generalized characteristic coordinate system (GCCS) proposed by Wu and Shi [1], the frame moves at a speed which is a linear combination of the convective speed and the sound speed, thus unifying the classical Eulerian approach, Lagrangian approach, and the unified coordinate system (UCS) of Hui and his co-workers [2]. Here some properties of Euler equations in the GCCS are studied and the advantages of GCCS in capturing expansion fans and shock waves are demonstrated by the results of numerical tests.

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A TRIAL SOLUTION APPROACH TO THE GI/M/1 QUEUE WITH N-POLICY AND EXPONENTIAL VACATIONS

  • Chae, Kyung-Chul;Lee, Sang-Min;Kim, Nam-Ki;Kim, Jin-Dong;Lee, Ho-Woo
    • Journal of the Korean Statistical Society
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    • v.33 no.3
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    • pp.283-298
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    • 2004
  • We present a trial solution approach to GI/M/l queues with generalized vacations. Specific types of generalized vacations we consider are N -policy and a combination of N-policy and exponential multiple vacations. Discussions about how to find trial solutions are given.

Calculation of Loss of Load Expectation and Loss of Load Frequency using a Moment matching method (모멘트 대입법에 의한 전력부족 기대치와 빈도수의 산정)

  • Yoo, Hyun-Ho;Kim, Jin-O
    • Proceedings of the KIEE Conference
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    • 1998.07c
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    • pp.1076-1078
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    • 1998
  • This paper proposes a new approach for calculating frequency and duration by using the moment matching technique. Two separate expressions are derived, one for the loss of load expectation(LOLE) and the other for the loss of load frequency(LOLF). These expressions are combination of exponentials and are therefore easily integrable and can be readily evaluated. The proposed approach is quite comparable of with the other methods at the aspect of accuracy and efficiency.

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Dissolved Gas Analysis Using the Dempster-Shafer Rule of Combination (Dempster-Shafer 결합 규칙을 이용한 유중 가스 분석법)

  • Yoon, Yong-Han;Kim, Jae-Chul
    • Proceedings of the KIEE Conference
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    • 1998.11a
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    • pp.301-303
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    • 1998
  • This paper presents a new approach to diagnose and detect faults in oil-filled power transformers based on various dissolved gas analyses. A theoretic fuzzy information model is introduced, An inference scheme which yields the 'most' consistent conclusion proposed. A framework is established that allows various dissolved gas analyses to be combined in a systematic way such as the Dempster-Shafer rule. Good diagnosis accuracy is obtained with the proposed approach.

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Analysis of the Lateral Motion of a Tractor-Trailer Combination (II) Operator/Vehicle System with Time Delay for Backward Maneuver

  • Mugucia, S.W.;Torisu, R.;Takeda, J.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.1147-1156
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    • 1993
  • In order to analyze lateral control in the backward maneuver of a tractor -trailer combination , a kinematic vehicle model and a human operator model with time delay were utilized for the operator/vehicle system. The analysis was carried out using the frequency domain approach. The open-loop stability of the vehicle motion was analyzed through the transfer functions. The sensitivity of the stability of the vehicle motion. to a change in the steering angle, was also analyzed. A mathematical model of the closed -loop operator/vehicle system was then formulated. The closed -loop stability of the operator /vehicle system was then analyzed. The effect of the delay time on the system was also analyzed through computer simulation.

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Successful Treatment of Post-operative Keloid with Combined Cryotherapy and Ablative Fractional CO2 Laser

  • Kim, Jihee;Lee, Young In;Lee, Ju Hee;Oh, Sang Ho;Lee, Sang Eun;Kim, Young Koo
    • Medical Lasers
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    • v.9 no.1
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    • pp.58-61
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    • 2020
  • Keloids are pathologic fibroproliferative conditions characterized by excessive collagen deposition during wound healing. The pathogenesis of keloids is not fully understood, and current treatment options show variable results. In this case report, the patient developed a keloid after bilateral total thyroidectomy, and was treated with a combination approach using fractional ablative laser systems along with cryotherapy and triamcinolone injection. After seven monthly sessions of combination treatment, the patient presented marked improvement of the scar texture and symptoms. Furthermore, there was no recurrence for up to 2 years. We propose this combination as a safe and effective treatment option for keloid patients.

Optimal Multi-Model Ensemble Model Development Using Hierarchical Bayesian Model Based (Hierarchical Bayesian Model을 이용한 GCMs 의 최적 Multi-Model Ensemble 모형 구축)

  • Kwon, Hyun-Han;Min, Young-Mi;Hameed, Saji N.
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1147-1151
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    • 2009
  • In this study, we address the problem of producing probability forecasts of summer seasonal rainfall, on the basis of Hindcast experiments from a ensemble of GCMs(cwb, gcps, gdaps, metri, msc_gem, msc_gm2, msc_gm3, msc_sef and ncep). An advanced Hierarchical Bayesian weighting scheme is developed and used to combine nine GCMs seasonal hindcast ensembles. Hindcast period is 23 years from 1981 to 2003. The simplest approach for combining GCM forecasts is to weight each model equally, and this approach is referred to as pooled ensemble. This study proposes a more complex approach which weights the models spatially and seasonally based on past model performance for rainfall. The Bayesian approach to multi-model combination of GCMs determines the relative weights of each GCM with climatology as the prior. The weights are chosen to maximize the likelihood score of the posterior probabilities. The individual GCM ensembles, simple poolings of three and six models, and the optimally combined multimodel ensemble are compared.

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A Study on the Stochastic Finite Element Method Based on Variational Approach (변분법을 이용한 확률론적 유한요소법에 관한 연구)

  • Bae, Dong-Myung;Kim, Kyung-Yull
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.32 no.4
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    • pp.432-446
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    • 1996
  • A stochastic Hamilton variational principle(SHVP) is formulated for dynamic problems of linear continuum. The SHVP allows incorporation of probabilistic distributions into the finite element analysis. The formulation is simplified by transformation of correlated random variables to a set of uncorrelated random variables through a standard eigenproblem. A procedure based on the Fourier analysis and synthesis is presented for eliminating secularities from the perturbation approach. In addition to, a method to analyse stochastic design sensitivity for structural dynamics is present. A combination of the adjoint variable approach and the second order perturbation method is used in the finite element codes. An alternative form of the constraint functional that holds for all times is introduced to consider the time response of dynamic sensitivity. The algorithms developed can readily be adapted to existing deterministic finite element codes. The numerical results for stochastic analysis by proceeding approach of cantilever, 2D-frame and 3D-frame illustrates in this paper.

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