• 제목/요약/키워드: Optimizing Parameters

검색결과 460건 처리시간 0.027초

신경회로망과 유한요소법을 이용한 편측식 선형유도전동기의 최적설계에 관한 연구 (Optimum Design of Single-Sided Linear Induction Motor Using the Neural Networks and Finite Element Method)

  • 임달호;박승찬;박두진;장석명;이철직
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 하계학술대회 논문집 B
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    • pp.1004-1006
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    • 1993
  • A new method for the optimal design of a single-sided linear induction motor(SLIM) is presented. The method utilizes the neural networks and finite element method for optimizing the design parameters of SLIM. The finite element analysis is used to produce a variety of neural networks training data and the neural networks is used for optimizing the design parameters by sequential unconstrained minimization technique(SUMT). As a result, it is known that the novel method is very efficient and accurate as an optimization technique.

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Determination of the Weighting Parameters of the LQR System for Nuclear Reactor Power Control Using the Stochastic Searching Methods

  • Lee, Yoon-Joon;Cho, Kyung-Ho
    • Nuclear Engineering and Technology
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    • 제29권1호
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    • pp.68-77
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    • 1997
  • The reactor power control system is described in the fashion of the order increased LQR system. To obtain the optimal state feedback gain vectors, the weighting matrix of the performance function should be determined. Since the contentional method has some limitations, stochastic searching methods are investigated to optimize the LQR weighting matrix using the modified genetic algorithm combined with the simulated annealing, a new optimizing tool named the hybrid MGA-SA is developed to determine the weighting parameters of the LQR system. This optimizing tool provides a more systematic approach in designing the LQR system. Since it can be easily incorporated with any forms of the cost function, it also provides the great flexibility in the optimization problems.

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시뮬레이션을 통한 시스템 최적화 과정에서 공통 난수 활용의 이점 분석 (A Benefit Analysis of Using Common Random Numbers When Optimizing a System by Simulation Experiments)

  • 박진원
    • 한국시뮬레이션학회논문지
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    • 제9권4호
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    • pp.1-10
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    • 2000
  • One of the primary goals of the simulation experiments is to understand the overall system behavior and to analyze the system, ultimately to optimize the system. Optimizing the system includes determining the optimum condition of the system parameters of interest. This paper is concerned with the simulation methodology for estimating the unknown objective function for the system of interest and optimizing the system with respect to the controllable factors. In the process of estimating the unknown objective function, which is assumed to be a second order spline function, we use common random numbers for different set of the controllable factors resulting in more accurate parameter estimation for the objective function. We will show some mathematical result for the benefit of using common random numbers.

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Analytical Calculation for Predicting the Air Gap Flux Density in Surface-Mounted Permanent Magnet Synchronous Machine

  • Feng, Yan-li;Zhang, Cheng-ning
    • Journal of Electrical Engineering and Technology
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    • 제12권2호
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    • pp.769-777
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    • 2017
  • The research of air gap flux density has a significant effect on predicting and optimizing the structure parameters of electrical machines. In the paper, the air gap coefficient, leakage flux factor and saturation coefficient are first analytically expressed in terms of motor properties and structure parameters. Subsequently, the analytical model of average air gap flux density for surface-mounted permanent magnet synchronous machines is proposed with considering slotting effect and saturation. In order to verify the accuracy of the proposed analytical model, the experiment and finite element analysis (FEA) are used. It shows that the analytical results keep consistency well with the experimental result and FEA results, and the errors between FEA results and analytical results are less than 5% for SPM with high power. Finally, the analytical model is applied to optimizing the motor structure parameters. The optimal results indicate that the analytical calculation model provides a great potential to the machine design and optimization.

Development of FK506-hyperproducing strain and optimization of culture conditions in solid-state fermentation for the hyper-production of FK506

  • Mo, SangJoon;Yang, Hyeong Seok
    • Journal of Applied Biological Chemistry
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    • 제59권4호
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    • pp.289-298
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    • 2016
  • FK506 hyper-yielding mutant, called the TCM8594 strain, was made from Streptomyces tsukubaensis NRRL 18488 by mutagenesis using N-methyl-N'-nitro-N-nitrosoguanidine, ultraviolet irradiation, and FK506 sequential resistance selection. FK506 production by the TCM8594 strain improved 45.1-fold ($505.4{\mu}g/mL$) compared to that of S. tsukubaensis NRRL 18488 ($11.2{\mu}g/mL$). Among the five substrates, wheat bran was selected as the best solid substrate to produce optimum quantities of FK506 ($382.7{\mu}g/g$ substrate) under solid-state fermentation, and the process parameters affecting FK506 production were optimized. Maximum FK506 yield ($897.4{\mu}g/g$ substrate) was achieved by optimizing process parameters, such as wheat bran with 5 % (w/w) dextrin and yeast extract as additional nutrients, 70 % (v/w) initial solid substrate moisture content, initial medium pH of 7.2, $30^{\circ}C$ incubation temperature, inoculum level that was 10 % (v/w) of the cell mass equivalent, and a 10 day incubation. The results showed an overall 234 % increase in FK506 production after optimizing the process parameters.

SHAP 분석 기반의 넙치 질병 분류 입력 파라미터 최적화 (Optimizing Input Parameters of Paralichthys olivaceus Disease Classification based on SHAP Analysis)

  • 조경원;백란
    • 한국전자통신학회논문지
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    • 제18권6호
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    • pp.1331-1336
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    • 2023
  • 머신러닝을 이용한 텍스트 기반 어류 질병 분류에서 머신러닝 모델의 입력 파라미터가 너무 많은 문제가 존재하지만, 성능의 문제로 임의로 입력 파라미터를 줄일 수 없다. 본 논문에서는 이 문제를 해결하고자 SHAP 분석 기법을 활용해 넙치 질병 분류에 특화된 입력 파라미터 최적화 방안을 제시한다. 제안한 방법은 SHAP 분석 기법을 적용하여 넙치 질병 문진표에서 추출한 질병 정보의 데이터 전처리와 AutoML을 활용한 머신러닝 모델 평가 과정을 포함한다. 이를 통해 AutoML의 입력 파라미터의 성능을 평가하고, 최적의 입력 파라미터 조합을 도출한다. 본 연구에서 제안 방법은 필요한 입력 파라미터 수를 감소시키면서도 기존의 성능을 유지할 수 있을 것으로 기대되며, 이는 텍스트 기반 넙치 질병 분류의 효율성 및 실용성을 높이는 데 기여할 것이다.

최적화 기법에 의한 원통형 유체 엔진마운트의 설계변수 동정 및 최적화 (Optimizing and Identification of Design Parameters of a Cylindrical Hydraulic Engine Mount by an Optimization Method)

  • 안영공
    • 동력기계공학회지
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    • 제21권3호
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    • pp.66-73
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    • 2017
  • In order to identify the design parameters of a hydraulic engine mount with a nonlinear characteristics, an experimental method has been used generally. The method takes a considerable time and expense because of preparing an experimental apparatus, conducting a test, and analyzing results. Therefore, this paper presents a simple method to identify the design parameters of a cylindrical hydraulic engine mount, and optimize the design parameters. The physical model and mathematical equations of the mount were derived, and values of the design parameters of the mount were identified by optimization method with minimizing difference between the analytical results with the equations and the experimental results. This method is more simpler than the conventional experiment method and identify successfully the design parameters. In addition, the technique can optimize the design parameters of the mount to improves the isolation performance of the mount.

유전 알고리듬을 이용한 자기동조 제어기 (A self tuning controller using genetic algorithms)

  • 조원철;김병문;이평기
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.629-632
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    • 1997
  • This paper presents the design method of controller which is combined Genetic Algorithms with the Generalized minimum variance self tuning controller. It is shown that the controllers adapts to changes in the system parameters with time delays and noises. The self tuning effect is achieved through the recursive least square algorithm at the parameter estimation stage and also through the Robbins-Monro algorithm at the stage of optimizing a polynomial parameters. The computer simulation results are presented to illustrate the procedure and to show the performance of the control system.

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ASTE receiver optics design using ultra wideband corrugated horn at combined ALMA band 7 and band 8 frequencies

  • Lee, Bangwon;Lee, Jung-won;Gonzalez, Alvaro
    • 천문학회보
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    • 제42권2호
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    • pp.57.3-58
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    • 2017
  • We report the detailed design of an unprecedented wideband(band7+8) corrugated feed horn in ASTE focal plane array aiming for future ALMA receiver. We have found that such design constraints as return loss, cross-polarization level, beam width and phase curvature can be controlled by optimizing critical corrugation parameters at the throat and flare region of the horn. The success of optimization manifest itself through simulated aperture effciency over 80 % at the entire frequency range. Physical implications of the resulting corrugation parameters are discussed.

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