• Title, Summary, Keyword: Optimal design

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Optimal Structural Design for the Electro-magnectic Launcher (전자력 발사기의 최적 구조 설계)

  • 이영신;안충호
    • Computational Structural Engineering
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    • v.9 no.2
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    • pp.143-151
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    • 1996
  • The optimal design for Electro-magnetic Launcher (EML : Rail Gun) considering structural and electrical constraints are presented. For the structure of EML under high pulsed currency, the cross section is minimized subject to maximum stress of each element(rail, side wall, ceramic, and steel) within allowable stress and preload limits. The electrical constraint is the effective ceramic thickness which prevents the eddy current effect reducing the performance of EML. The stress analysis and optimization procedure of 90mm EML is conducted with ANSYS Code. The optimal design under preload is reduced to 53% of area compared with optimal design without preload. In case of rail with arc angle .theta.=45.deg., the performance of EML is the best among the other rail arc angles. The optimal design for rail with arc angle .theta.=45.deg., results in the reduction of 9% of area and 10.4% of deformation compared with Fahrenthold's design. The optimal preload 59.8MPa is much lower than Fahrenthold's design(186MPa). The results show that the optimal design of EML meets the design requirements.

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Multiobjective Decision-Making applied to Ship Optimal Design

  • Wang, Li-Zheng;Xi, Rong-Fei;Bao, Cong-Xi
    • Journal of Ship and Ocean Technology
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    • v.5 no.1
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    • pp.30-37
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    • 2001
  • Ship optimal design is a multi-objective decision-making process and its optimal solution does not exit in general. It is a problem in which the decision-maker is very interested that an effective solution is how to be found which has good characteristic and is substituted for optimal solution in a sense. In the previous methods of multi-objective decision-making, the weighting coefficients are decided from the point of view of individuals which have a bit sub-jective an unilateral behavior. in order to fairly and objectively decide the weighting coeffi-cients, which are considered to be optimal in all system of multi-objective decision-making and satisfactory solution to the decision-maker, the pater presents a method of applying the Technology of the Biggest Entropy. It is proved that the method described in the paper is very feasible and effective be means of a practical example of ship optimal design.

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Experimental Verification for Optimal Efficiency Model of Inverter-Fed Induction Motor (인버터 구동 유도 전동기의 최적 효율 모델 확인 실험)

  • 김재우;김병택;권병일
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.53 no.5
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    • pp.277-282
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    • 2004
  • The optimal design of the rotor slot for inverter-fed induction motor was performed. The purpose of the paper is to verify the optimal point by experiment. A sensitivity analysis is performed, and the models near to an optimal point are selected. In the selecting process of models, 2 design variables with high sensitivity are selected out of 5 design variables. On the basis of the selected variables, 2 models near to the optimal point are decided. The tim e-step F.E.A and the experiment are performed. Optimal point and performance improvement of the optimal mode are verified.

Framwork for task based design of robot manipulators

  • Kim, Jin-Oh;Khosla, Pradeep-K.
    • 제어로봇시스템학회:학술대회논문집
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    • pp.497-502
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    • 1992
  • In this paper, a new design technique called Task Based Design (TBD) is proposed to design an optimal robot manipulator for a given task. Optimal design of a manipulator is difficult because it involves implicit and highly nonlinear functions of many design variables for a complex task. TBD designs an optimal manipulator which performs a given task best, by using a framework called Progressive Design which decomposes the complexity of the task into three steps: kinematic design, planning and kinematic control. An example of TBD is presented to demonstrate the efficiency and effectiveness of our framework.

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Integrated Optimal Design of Smart Connective Control System and Connected Buildings (스마트 연결 제어 시스템과 연결 구조물의 통합 최적 설계)

  • Kim, Hyun-Su;Kang, Joo-Won
    • Journal of the Korean Association for Spatial Structures
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    • v.19 no.2
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    • pp.43-50
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    • 2019
  • A smart connective control system was invented recently for coupling control of adjacent buildings. Previous studies on this topic focused on development of control algorithm for the smart connective control system and design method of control device. Usually, a smart control devices are applied to building structures after structural design. However, because structural characteristics of building structure with control devices changes, a iterative design is required for optimal design. To defeat this problem, an integrated optimal design method for a smart connective control system and connected buildings was proposed. For this purpose, an artificial seismic load was generated for control performance evaluation of the smart coupling control system. 20-story and 12-story adjacent buildings were used as example structures and an MR (magnetorheological) damper was used as a smart control device to connect adjacent two buildings. NSGA-II was used for multi-objective integrated optimization of structure-smart control device. Numerical simulation results show the integrated optimal design method proposed in this study can provide various optimal designs for smart connective control system and connected buildings presenting good control performance.

The Arrangement of Heaters for Rubber Injection Molds using FEM and Optimal Design Method (유한요소법과 최적설계 기법을 이용한 고무 사출 금형 히터 배치)

  • Kim, Myung-Hun;Han, Jeong-Young;Choi, Eun-Ho;Bae, Won-Byong;Kang, Sung-Soo
    • Journal of The Korean Society of Manufacturing Technology Engineers
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    • v.20 no.1
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    • pp.34-39
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    • 2011
  • Temperature control of a rubber injection mold is important for the dimensional accuracy of product. The main objective of this paper is to optimize the arrangement of heaters by FEM and optimal design method. Firstly, 3-dimensional transient heat transfer analysis was carried out for a square specimen mold. Results of FE analysis are a good agreement with the experimental results, showing about 1.22~7.22% error in temperature distribution. Secondly, we suggested the optimal method about an arrangement of heaters of rubber injection mold by using the optimal design technique. Distances between heater's center and the contact surface of mold, distances between heater's center and symmetric surface were considered as design variables. And the variances between the temperatures of cavity surfaces and their average temperature were used as the objective functions. Applying the optimal solution, the temperature variation was improved about 52.9~88.1 % compared to the existing mold. As a result of sensitivity analysis for design variables, design variables parallel to the direction of the split plane in mold affect the largest on the surface temperature variation in mold cavity.

Optimal Design of a Flextensional Transducer Considering All the Cross-coupled Effects of the Design Variables (설계변수들의 상호효과를 고려한 Flextensional 트랜스듀서의 최적설계)

  • 강국진;노용래
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.13 no.5
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    • pp.364-374
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    • 2003
  • The performance of an acoustic transducer is determined by the effects of many design variables. and mostly the influences of these design variables are not linearly independent of each other To achieve the optimal performance of an acoustic transducer, we must consider the cross-coupled effects of the design variables. In this study with the FEM. we analyzed the variation of the resonance frequency and sound pressure of a flextensional transducer in relation to Its design variables. Through statistical multiple regression analysis of the results, we derived functional forms of the resonance frequency and sound pressure in terms of the design variables, and with which we determined the optimal structure of the transducer by means of a constrained optimization technique, SQP-PD. The proposed method can reflect all the cross-coupled effects of multiple design variables, and can be utilized to the design of general acoustic transducers.

SDRE-Based Near Optimal Traffic Controller Design (SDRE 기반 준최적 교통 혼잡 제어기 설계)

  • Choi, Han Ho
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.12
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    • pp.1086-1089
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    • 2012
  • We propose a near optimal controller design method for ramp metering based on SDRE (State Dependent Riccati Equation) approach. We parameterize the optimal nonlinear controller in terms of the solution matrices of an SDRE. We also give a simple algorithm to obtain the controller gain. Finally we give numerical results to show the effectiveness of the proposed near optimal traffic controller design method.

Optimal supervisory control for multiple-modelled discrete event systems

  • Lee, Moon-Sang;Lim, Jong-Tae
    • 제어로봇시스템학회:학술대회논문집
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    • pp.73.5-73
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    • 2001
  • In this paper, we present a procedure to design the robust optimal supervisor which has the minimal cost in the sense of average for a given multiple-modelled discrete event system DES. In order to design the robust optimal supervisor, we extend the optimal supervisor design algorithm for a deterministic DES to the case of multiple-modelled DESs. In addition, using the proposed algorithm with modified costs of events and penalities of states, we can show whether a robust supervisor for a given multiple-modelled DES exists and design the minimally restricted robust supervisor.

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An Application of Optimal Blank Design by the Sensitivity Analysis to the Stampings of General Shaped Parts (민감도법을 이용한 최적블랭크 설계법의 일반적인 모양의 금형에의 적용)

  • 심현보;손기찬;황현태
    • Transactions of Materials Processing
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    • v.9 no.3
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    • pp.226-232
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    • 2000
  • The optimal blank design method by sensitivity analysis has been applied to the formings of oil-pan, tailored blank and front panel as the examples. Die geometry is prepared by a commercial CAD system. Excellent results has been obtained between the numerical results and the target contour shapes. Through the investigation, the proposed systematic method of optimal blank design is found to be effective in the practical forming processes.

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