• 제목/요약/키워드: design of algorithms

검색결과 2,703건 처리시간 0.031초

Structural optimization in practice: Potential applications of genetic algorithms

  • Krishnamoorthy, C.S.
    • Structural Engineering and Mechanics
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    • 제11권2호
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    • pp.151-170
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    • 2001
  • With increasing competition, the engineering industry is in need of optimization of designs that would lead to minimum cost or weight. Recent developments in Genetic Algorithms (GAs) makes it possible to model and obtain optimal solutions in structural design that can be put to use in industry. The main objective of this paper is to illustrate typical applications of GAs to practical design of structural systems such as steel trusses, towers, bridges, reinforced concrete frames, bridge decks, shells and layout planning of buildings. Hence, instead of details of GA process, which can be found in the reported literature, attention is focussed on the description of the various applications and the practical aspects that are considered in Genetic Modeling. The paper highlights scope and future directions for wider applications of GA based methodologies for optimal design in practice.

삼각 패치 알고리듬을 이용한 복합 재료 구조물의 전체 최적화 (Global Optimization of Composite Structures Using Triangular Patch Algorithm)

  • 오승환;이병채
    • 대한기계학회논문집A
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    • 제25권4호
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    • pp.671-684
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    • 2001
  • Several design problems of composite structures are studied via a global optimizer based on attraction regions. MSC/NASTRAN is adopted for static and eigenvalue analysis. The method of modified feasible direction in DOT is used for local optimization. Through the review of global optimization algorithms, the triangular patch algorithm is selected because the algorithm is known to be efficient, robust and powerful for general nonlinear optimization problems. For general applicability, various mechanical properties are considered as design objectives; strain energy, eigenvalue, weight, displacement, and buckling load. In all cases considered, the triangular patch algorithm results in a lot of optimum points and useful design patterns, that are not easy by local algorithms or conventional global algorithms can be determined.

계층적 공정 경쟁 유전자 알고리즘을 이용한 회전형 역 진자 시스템의 최적 캐스케이드 제어기 설계 (Design of Optimized Cascade Controller by Hierarchical Fair Competition-based Genetic Algorithms for Rotary Inverted Pendulum System)

  • 정승현;장한종;오성권
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.104-106
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    • 2007
  • In this paper, we propose an approach to design of optimized Cascade controller for Rotary Inverted Pendulum system using Hierarchical Fair Competition-based Genetic Algorithm(HFCGA). GAs may get trapped in a sub-optimal region of the search space thus becoming unable to find better quality solutions, especially for very large search space. The Parallel Genetic Algorithms(PGA) are developed with the aid of global search and retard premature convergence. HFCGA is a kind of multi-populations of PGA. In this paper, we design optimized Cascade controller by HFCGA for Rotary Inverted Pendulum system that is nonlinear and unstable. Cascade controller comprise two feedback loop, parameters of controller optimize using HFCGA. Then designed controller evaluate by apply to the real plant.

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진화론적 알고리즘에 의한 퍼지 다항식 뉴론 기반 고급 자기구성 퍼지 다항식 뉴럴 네트워크 구조 설계 (Design of Advanced Self-Organizing Fuzzy Polynomial Neural Networks Based on FPN by Evolutionary Algorithms)

  • 박호성;오성권;안태천
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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    • pp.322-324
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    • 2005
  • In this paper, we introduce the advanced Self-Organizing Fuzzy Polynomial Neural Network based on optimized FPN by evolutionary algorithm and discuss its comprehensive design methodology involving mechanisms of genetic optimization, especially genetic algorithms (GAs). The proposed model gives rise to a structurally and parametrically optimized network through an optimal parameters design available within Fuzzy Polynomial Neuron(FPN) by means of GA. Through the consecutive process of such structural and parametric optimization, an optimized and flexible the proposed model is generated in a dynamic fashion. The performance of the proposed model is quantified through experimentation that exploits standard data already used in fuzzy modeling. These results reveal superiority of the proposed networks over the existing fuzzy and neural models.

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An approach to the interactive design process using genetic algorithms

  • Okuno, Taku;Kakazu, Yukinori
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.281-284
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    • 1992
  • This paper is aiming to apply the Genetic Algorithms (GAs) to the interactive design. For that purpose, the scheme for utilizing the past design processes for the next interactive design process is proposed. In this scheme, the process consists of three phases: the searching phase, the tuning phase and the design phase. The first phase searches the optimal decision sequences for the past design instances by GAs. By the collected sequences, the second phase tunes the criteria of selecting decision sequences for the next design process. By this scheme, the implicit constraints satisfied in the past design can be applied to the next design. Finally, the computer simulations on the simple gear-train design were carried out to show the effectiveness of the scheme.

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화방 정찰 체계에서의 다수의 이동 로봇을 위한 시간 효율적인 경로 계획 알고리즘에 대한 연구 (Time-Efficient Trajectory Planning Algorithms for Multiple Mobile Robots in Nuclear/Chemical Reconnaissance System)

  • 김재성;김병국
    • 제어로봇시스템학회논문지
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    • 제15권10호
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    • pp.1047-1055
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    • 2009
  • Since nuclear and chemical materials could damage people and disturb battlefield missions in a wide region, nuclear/chemical reconnaissance systems utilizing multiple mobile robots are highly desirable for rapid and safe reconnaissance. In this paper, we design a nuclear/chemical reconnaissance system including mobile robots. Also we propose time-efficient trajectory planning algorithms using grid coverage and contour finding methods for reconnaissance operation. For grid coverage, we performed in analysis on time consumption for various trajectory patterns generated by straight lines and arcs. We proposed BCF (Bounded Contour Finding) and BCFEP (Bounded Contour Finding with Ellipse Prediction) algorithms for contour finding. With these grid coverage and contour finding algorithms, we suggest trajectory planning algorithms for single, two or four mobile robots. Various simulations reveal that the proposed algorithms improve time-efficiency in nuclear/chemical reconnaissance missions in the given area. Also we conduct basic experiments using a commercial mobile robot and verify the time efficiency of the proposed contour finding algorithms.

유전 알고리즘을 이용한 디젤 엔진의 최적 연료주입 모델 추종형 ${\mu}$-합성 제어 시스템의 설계 (A Design on Model Following ${\mu}$-Synthesis Control System for Optimal Fuel-Injection of Diesel Engine Using Genetic Algorithms)

  • 김동완;황현준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 B
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    • pp.587-589
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    • 1997
  • In this paper we design the model following ${\mu}$-synthesis control system for optimal fuel-injection of diesel engine using genetic algorithms. To do this, we give gain and dynamics parameters to the weighting functions and apply genetic algorithms with reference model to the optimal determination of weighting functions that are given by D-K iteration method which can design ${\mu}$-synthesis controller in the state space. These weighting functions are optimized simultaneously in the search domain selected adequately. The effectiveness of this ${\mu}$-synthesis control system for fuel-injection is verified by computer simulation.

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변위계수법을 활용한 최적 내진 성능기반 설계기법 개발 (Development of Optimal Performance based Seismic Design Method using Displacement Coefficient Method)

  • 이현국;권윤한;박효선
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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    • pp.103-110
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    • 2004
  • Recently, performance based seismic design (PBSD) methods in numerous forms have been suggested and widely studied as a new concept of seismic design. The PBDSs are far from being practical due to complexity of algorithms resided in the design philosophy In this paper, optimal seismic design method based on displacement coefficient method (DCM) described in FEMA 273 is developed. As an optimizer simple genetic algorithms are used for implementations. In the optimization problem formulated in this paper, strength design criteria, stiffness design criteria, and nonlinear response criteria specified in DCM are included in design constraints. The optimal performance based design(OPBD) method is applied to seismic design of a 9-story two-dimensional steel frame structures.

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2차원 철골 구조물의 최적 성능기반 내진설계법 개발 (Development of the Optimal Performance Based Seismic Design Method for 2D Steel Moment Resisting Frames)

  • 권봉근;이현국;권윤한;박효선
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2005년도 춘계 학술발표회 논문집
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    • pp.636-643
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    • 2005
  • Recently, performance based seismic design (PBSD) methods have been suggested in numerous forms and widely studied as a new concept of seismic design. The PBDSs are far from being practical method due to complexity of algorithms resided in the design philosophy. In this paper, optimal seismic design method based on displacement coefficient method (DCM) described in FEMA 273 is developed. As an optimizer simple genetic algorithms are used for implementations. In the optimization problem formulated in this Paper, strength design criteria stiffness design criteria, and nonlinear response criteria specified in DCM are included in design constraints. The optimal performance based design(OPBD) method is applied to seismic design of a 3-story two-dimensional steel frame structures.

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사물인터넷 기기를 위한 통합 보안 코어의 하드웨어 설계 (The Hardware Design of Integrated Security Core for IoT Devices)

  • ;류광기
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2017년도 추계학술대회
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    • pp.584-586
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    • 2017
  • 본 논문에서는 인터넷 장치의 보안을 위해 경량 대칭 암호화와 경량 인증을 통합 한 하드웨어 아키텍처를 제안한다. 암호화 핵심은 PRESENT 알고리즘과 제안된 새로운 경량 암호화 알고리즘으로 구성된다. 또한 HB 및 HB +, HB-MP, HB-MP + 인증 알고리즘들을 포함한다. 통합 보안 시스템은 Verilog HDL을 사용하여 설계되었으며 Modelsim SE 및 Xilinx Design Suite 14.3 프로그램을 사용하여 검증 및 합성되었다. 제안하는 암호화 코어 하드웨어 구조는 Spartan6 FPGA 장치에서 합성한 결과 189Mhz 주파수와 1130개 슬라이스를 가진다.

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