• 제목/요약/키워드: SUMT method

검색결과 44건 처리시간 0.021초

FTM을 이용한 파형격벽의 최적구조설계 (Optimum Structural Design of a Corrugated Bulkhead by using Flexible Tolerance Method)

  • 임상전;김기화;양영순
    • 대한조선학회지
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    • 제24권4호
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    • pp.45-52
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    • 1987
  • In this paper, merits and demerits of Nelder and Mead Penalty Function Method(SUMTNM) and Flexible Tolerance Method(FTM) are investigated from the standpoint of generality, accuracy and efficiency. SUMTNM is combined with Nelder and Method and SUMT, but FTM improves the values of the objective function by using information provided by feasible points as well as certain nonfeasible points termed near-feasible points. Therefore, FTM uses more information than SUMTNM for minimizing object function. The structural analysis of a vertically corrugated bulkhead is performed by collapse mechanism and plate buckling analysis. Based on the results of this analysis, minimum structural weight design of a corrugated bulkhead by use of above two optimization techniques is carried out by investigating the effects of sizes of bulkhead on the structural weight.

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전자계산기에 의한 배전선료전선 단면적의 경제적 설계법 (A Computer method in Economical Design of Conductor Sizes of Distribution Lines)

  • 박영문
    • 전기의세계
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    • 제24권5호
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    • pp.107-110
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    • 1975
  • This paper describes computational algorithms and a computer program for optimum determinations of wire conductor sizes of radial or tree-type distibution lones with given constraints. Here, The objective function is defined as the total summation of the volume or weight of respective conductor materials required for buildingup the entire distributing system. Four categories of constraints are applied to the obiective function. That is, on the respective load points constraint is imposed by a specified voltage drop limit, and the respective line elements are capable of carrying the current safely(safety current) and also must maintain the minimum thickness in viewpoint of mechanical strength and legal requirements. And finally, the conductor sizes have to be selected among the standardized size levels of the products. These kinds of optimization problems cannot be solved by the ordinary optimization tediniques such as the Linear Programming Method, SUMT Technique, etc. This paper, therefore, successfully devised the powerful alorithms to solve the problem, using the particular properties or characteristics ingerent to the radial or tree-type distribution system. The computer program developed from the algorithms was applied to several sample systems and shown to be exact and very efficient.

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초기설계단계(初期設計段階)에서의 콘테이너선(船)의 경제성(經濟性)에 관한 연구(硏究) (A Study on the Economics of Container Ships at Preliminary Design Stage)

  • 이동곤;마순일
    • 대한조선학회지
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    • 제21권2호
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    • pp.1-7
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    • 1984
  • This paper is concerned with an optimum design study of containerships in preliminary stage by applying economic criteria. The Net Present Value Index (NPVI) and the Required Freight Rate(RFR) are used as measures of merit. Hooke & Jeeves direct search method and External Penalty Function method of Sequential Unconstrained Minimization Techniques(SUMT) are used for solving constrained nonlinear optimization problem. Sensitivity analysis is carried out to investigate the effect on the optimum solution due to change of values in some parameters such as crane capacity, load factor, oil price, ship speed and the ratio between loaded FEU and TEU.

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송풍기 설계를 위한 수치최적설계기법의 응용 (Application of Numerical Optimization Technique to the Design of Fans)

  • 김광용;최재호;김태진;류호선
    • 설비공학논문집
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    • 제7권4호
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    • pp.566-576
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    • 1995
  • A Computational code has been developed in order to design axial fans by the numerical optimization techniques incorporated with flow analysis code solving three-dimensional Navier-Stokes equation. The steepest descent method and the conjugate gradient method are used to look for the search direction in the design space, and the golden section method is used for one-dimensional search. To solve the constrained optimization problem, sequential unconstrained minimization technique, SUMT, is used with imposed quadratic extended interior penalty functions. In the optimization of two-dimensional cascade design, the ratio of drag coefficient to lift coefficient is minimized by the design variables such as maximum thickness, maximum ordinate of camber and chord wise position of maximum ordinate. In the application of this numerical optimization technique to the design of an axial fan, the efficiency is maximized by the design variables related to the sweep angle distributed by quadratic function along the hub to tip of fan.

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입체 반송용 선형유도전동기의 설계 변수 최적화에 대하여 (On the optimization of the design variables of linear induction motor for 3-D conveyor system)

  • 임달호;김규탁;박승찬
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1991년도 하계학술대회 논문집
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    • pp.139-142
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    • 1991
  • The design variables of SLIM used for 3-D conveyor system are optimized by nonlinear programing. Five design variables are selected as independent ones and object function is expressed as a combination of the weight and the normal force of the motor. Maximum flux density in the teeth, primary length and starting thrust are chosen as constraint functions. Goodness factor considering of conveying characteristic is also included in the constraints. In this paper sequential unconstrained minimization technique(SUMT) and variable metric method are used to solve the nonlinear problem.

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최소중량(最小重量) 및 건조비(建造費)를 위한 유조선(油槽船) 중앙단면(中央斷面) 설계(設計)에 관한 연구(硏究) (A Study on the Minimum Weight and/or Cost Design of a Midship Structure of Oil Tanker)

  • 김재근;어민우;신종계
    • 대한조선학회지
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    • 제20권2호
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    • pp.21-26
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    • 1983
  • In this light of economical engineering, the optimal configurations of ship structure that can save weights, production costs and operation costs should be investigated. This paper presents the general method of optimization based on non-linear programming and its application to weight and/or cost minimization of ship structure. Oil tanker is chosen as a ship type because of simple layout and easy calculation of stress. With the data of 16,200 DWT oil tanker built by KSEC 1980, this paper shows the procedure mentioned above by means of SUMT combined with two selected search methods. Then the differences between original and redesigned tanker structures are discussed.

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선박기본설계과정(船舶基本設計過程)에서의 경제성검토(經濟性檢討)와 최적화기법(最適化技法)의 응용(應用) (Economic Optimization in Preliminary Ship Design)

  • 김재근;한순흥
    • 대한조선학회지
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    • 제15권4호
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    • pp.1-5
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    • 1978
  • The preliminary ship design step is made into a non-linear programming(NLP) problem. And using SUMT-exterior method and Hook Jeeves pattern search, the optimum ship characteristics are determined for the case where the ship is built in Korea and is operated by Koreans. Three programs for bulk carrier, tanker, and container ship are constructed and several sensitivity tests are performed. The result has little difference from the results of the other papers, but for high interest rate of return, slightly larger and faster ship is superior, and for low labour costs, slightly smaller and slower ship is superior.

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반강접 접합부를 고려한 철골 구조물의 2차 탄성 해석 및 최적설계 (Second-Order Elastic Analysis and Optimum Design Considering Semi-Rigid Connection for Steel Structures)

  • 구본율;박춘욱;강성원;강문명
    • 한국공간구조학회논문집
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    • 제3권1호
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    • pp.35-46
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    • 2003
  • Conventional analysis and design of steel structures are performed using the assumption of a either fully rigid or pinned. However, every steel connection lies in between fully rigid and pinned connection. So, It is important to consider the connection for steel structure design. In this paper Computer-based second-order elastic analysis is used to calculate one story two bay and two story three bay for steel structures with semi-rigid connection. Genetic Algorithms(GAs) and Sequential Unconstrained Minized Technique(SUMT) dynamic programming is used to the method for optimum design of steel structures. The efficiency and validity of the developed continuous and discrete optimum design algorithm was verified by applying the algorithm to optimum design examples.

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원형 단순 확장소음기의 성능향상을 위한 입.출구 위치의 최적설계 (Optimum Design for Inlet and Outlet Locations of Circular Expansion Chamber for Improving Acoustic Performance)

  • 안세진;김봉준;정의봉
    • 대한기계학회논문집A
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    • 제24권10호
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    • pp.2487-2495
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    • 2000
  • The acoustic characteristics of expansion chamber will be changed with the variation of inlet/outlet location due to the higher order acoustic mode in a high frequency in which the plane wave theory is not available. In this paper, the acoustic performance of reactive type expansion chamber with circular cross-section is analyzed by using the modified mode matching theory. The sensitivity analysis of four-pole parameters with respect to the location of inlet and outlet is also suggested to increase the acoustic performance. The acoustic power transmission coefficient is used as cost function, and the location of inlet and outlet is used as design variables. The steepest descent method and SUMT algorithm are used for optimization technique. Several results showed that the expansion chamber with optimally located inlet/outlet had better acoustic performance than concentric expansion chamber.

단순강판형 단면의 최적설계를 위한 효율적인 비선형계획기법 (Efficient NLP Techniques for the Optimum Design of Simple Steel Plate Girder Cross Section)

  • 김종옥
    • 한국농공학회지
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    • 제36권2호
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    • pp.111-122
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    • 1994
  • In this study, an algorithm which can be applied to the optimum design of simple steel plate girders was developed, and efficient optimization strategies for the solution of algorithm were found out. The optimum design algorithm consists of 3-levels of optimization. In the first and second levels of optimization, the absolute maximum bending moment and shearing force are extracted and in the third level of optimization, the optimum cross section of steel plate girder is determined. For the optimum design of cross section, the objective function is formulated as the total area of cross section and constraints are derived in consideration of the various stresses and the minimum dimension of flange and web based on the part of steel bridge in the Korea standard code of road bridge. Sequential unconstrained minimization technique using the exterior penalty function method(SUMT-EP), sequential linear programming(SLP) and sequential quadratic programming (SQP) are proved to be efficient and robust strategies for the optimum design of simple plate girder cross section. From the reliable point of view, SLP is the most efficient and robust strategy and SQP is the most efficient one from the viewpoint of converguency and computing time.

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