• Title/Summary/Keyword: 최적이론

Search Result 1,517, Processing Time 0.027 seconds

최적설계 (I)

  • 곽병만
    • Journal of the KSME
    • /
    • v.23 no.1
    • /
    • pp.37-43
    • /
    • 1983
  • 본 강좌에서는 최적설계를 일반적인 설계 과정의 일부로 그 개념을 소개하고, 기계공학 시스템 에서 최적설계 분야의 개괄과 구체적인 최적화에 대한 이론을 간략하게 수회에 걸쳐 소개하며 분야별 적용예제를 보이고자 한다. 한가지 주의할 것은 최적화의 좋은 점만 생각하다 보면 설 계의 응용에 있어서 문제의 정립이 잘못 되거나, 컴퓨터와 인력에 대한 과다한 노력이 타당화 될 수 없는 문제 등에, 충분한 검토 없이 무작정 응용하는 것은 때때로 그 결과의 무용함은 물론 이고 여러가지 역효과를 남기게 될 것이다.

  • PDF

KLA 물류능력개발 프로그램 안내

  • 한국물류협회
    • LOGISTICS
    • /
    • no.7
    • /
    • pp.45-47
    • /
    • 2003
  • (사)한국물류협회(회장 서병륜)는 물류관련 업체 임직원을 대상으로 2003년 물류능력개발 프로그램을 개설하고 전문적인 교육을 실시하고 있다. 협회가 6월, 7월, 8일 및 9월에 개설한 $\triangle$창고관리 및 레이아웃 개선의 이론과 실무$\triangle$최적재고관리의 실천실무$\triangle$SCM 및 E-SCM구축을 위한 이론$\triangle$물류센터의 투자채산성 이론$\triangle$재고관리 이론과 실무$\triangle$$\cdot$배송시스템 구축실무이론 등의 총6개 과정의 프로그램에 대해 소개한다. 교육에 대한 자세한 사항은 한국물류협회 연수팀으로 문의하면 된다. (전화 : 02-706-0823)

  • PDF

Multi-Objective Fuzzy Optimization of Structures (구조물에 대한 다목적퍼지최적화)

  • Park, Choon-Wook;Pyeon, Hae-Wan;Kang, Moon-Myung
    • Journal of Korean Society of Steel Construction
    • /
    • v.12 no.5 s.48
    • /
    • pp.503-513
    • /
    • 2000
  • This study treats the criteria, considering the fuzziness occurred by optimization design. And we applied two weighting methods to show the relative importance of criteria. This study develops multi-objective optimization programs implementing plain stress analysis by FEM and discrete optimization design uniformaly. The developed program performs a sample design of 10-member steel truss. This study can carry over the multi-objective optimization based on total system fuzzy-genetic algorithms while performing the stress analysis and optimization design. Especially, when general optimization with unreliable constraints is cannot be solve this study can make optimization design closed to realistic with fuzzy theory.

  • PDF

Unified Section and Shape Discrete Optimum Design of Planar and Spacial Steel Structures Considering Nonlinear Behavior Using Improved Fuzzy-Genetic Algorithms (개선된 퍼지-유전자알고리즘에 의한 비선형거동을 고려한 평면 및 입체 강구조물의 통합 단면, 형상 이산화 최적설계)

  • Park, Choon Wook;Kang, Moon Myung;Yun, Young Mook
    • Journal of Korean Society of Steel Construction
    • /
    • v.17 no.4 s.77
    • /
    • pp.385-394
    • /
    • 2005
  • In this paper, a discrete optimum design program was developed using the refined fuzzy-genetic algorithms based on the genetic algorithms and the fuzzy theory. The optimum design in this study can perform section and shape optimization simultaneously for planar and spatial steel structures. In this paper, the objective function is the weight of steel structures and the constraints are the design limits defined by the design and buckling strengths, displacements, and thicknesses of the member sections. The design variables are the dimensions and coordinates of the steel sections. Design examples are given to show the applicability of the discrete optimum design using the improved fuzzy-genetic algorithms in this study.

Strategic Tariff Policy under Asymmetric Information (비대칭정보하에서의 전략적 최적관세 결정)

  • Lee, Jongmin
    • International Area Studies Review
    • /
    • v.15 no.1
    • /
    • pp.59-86
    • /
    • 2011
  • This paper examines a country's strategic optimal tariff policy against a foreign firm with market power. That is, the purpose of the paper is, under asymmetric information, to reexamine the problem of optimal tariff policy against a foreign monopolist from another country's welfare standpoint. This is to extend the analysis of Brander and Spencer(1984) which is both analytic and elaborate. The incentive compatible tariff schedule is derived, and then policy implications are investigated. The main result is that, under incomplete information, the optimal tariff is elevated above its full-information counterpart in order to capture foreign rents. Moreover, it suggests that trade policies motivated by rent extraction are unlikely to be robust to the introduction of incomplete information. This research complements an existing literature on the strategic trade policy in terms of asymmetric information.

Structural Design Optimization of Dynamic Crack Propagation Problems Using Peridynamics (페리다이나믹스를 이용한 균열진전 문제의 구조 최적설계)

  • Kim, Jae-Hyun;Park, Soomin;Cho, Seonho
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.28 no.4
    • /
    • pp.425-431
    • /
    • 2015
  • Based on a bond-based peridynamics theory for dynamic crack propagation problems, this paper presents a design sensitivity analysis and optimization method. Peridynamics has a peculiar advantage over the existing continuum theory in the mathematical modelling of problems where discontinuities arise. For the design optimization of the crack propagation problems, a non-shape design sensitivity is derived using the adjoint variable method. The obtained adjoint sensitivity of displacement and strain energy turns out to be very accurate and efficient compared to the finite different sensitivity. The obtained design sensitivities are futher utilized to optimally control the position of bifurcation point in the design optimization of crack propagation in a plate under tension. A numerical experiment demonstrates that the optimal distribution of material density could delay the position of bifurcation.

Determination of Optimal Pressure Monitoring Locations for Water Distribution Systems using Entropy Theory (엔트로피 이론을 이용한 상수관망의 최적 압력 계측 위치 결정)

  • Chung, Gun-Hui;Chang, Dong-Eil;Yoo, Do-Guen;Jun, Hwan-Don;Kim, Joong-Hoon
    • Journal of Korea Water Resources Association
    • /
    • v.42 no.7
    • /
    • pp.537-546
    • /
    • 2009
  • Determination of optimal pressure monitoring location is essential to manage water distribution system efficiently and safely. In this study, entropy theory is applied to overcome defects of previous researches about determining the optimal sensor location. The previous studies required the calibration using historical data, therefore, it was difficult to apply the proposed method in the place where the enough data were not available. Also, most researches have focused on the locations to minimize cost and maximize accuracy of the model, which is not appropriate for the purpose of maintenance of the water distribution system. The proposed method in this study quantify the entropy which is defined as the amount of information calculated from the pressure change due to the variation of discharge. When abnormal condition is occurred in a node, the effect on the entire network is presented by the entropy, and the emitter is used to reproduce actual pressure change pattern in EPANET. The optimal location to install pressure sensors in water distribution system is the nodes having the maximum information from other nodes. The looped and branched networks are evaluated using the proposed model. As a result, entropy theory provides general guideline to select the locations to install pressure sensors and the results can be used to help decision makers.

Study into prosodic morphological analysis in Korean and Standard Chinese partial reduplication and contrastive analysis using optimality theory (한국어와 표준 중국어 부분 중첩 의성·의태어에 대한 운율 형태론적 분석의 문제와 최적성 이론적 분석을 통한 대조 분석)

  • Chang, Jae-Woong
    • Cross-Cultural Studies
    • /
    • v.49
    • /
    • pp.275-301
    • /
    • 2017
  • Based on the previous analysis by Wanghongjun(2008), this paper applies Optimality Theory (OT) to the field of partial reduplication in Korea to increase its scientific validity. Toward this end, I propose an alternative analysis of Korean partial reduplication, applied as a single process of prefixation. Reduplicated words by prefixation are divided into two types: with a heavy syllable of the stem, and another with the stem. The two types of partial reduplication are closely related by the sound features. In addition, I discussed Chinese partial reduplication from a prefixation perspective within the framework of OT and performed contrastive analysis of Korean and Standard Chinese processes of reduplication by focusing on constrained rankings. As a result, the alternative analysis showed a systematic relationship among the reduplicated words in Korean and Standard Chinese. Lastly, I explained that the coronal /t/ and liquid /l/ have a special functional hierarchy in both languages. This study can be re-explained based on the framework of OT according to a few major constraints, involving MAX-BR, MAX-IO. Their rankings show the adequacy of analysis.

Composite Design Criteria : Model and Variance (복합실험기준의 설정: 모형과 분산구조)

  • 김영일
    • The Korean Journal of Applied Statistics
    • /
    • v.13 no.2
    • /
    • pp.393-405
    • /
    • 2000
  • Box and Draper( 19(5) listed some properties of a design that should be considered in design selection. But it is impossible that one design criterion from optimal experimental design theory reflects many potential objectives of an experiment, because the theory was originally based on the underlying model and its strict assumption about the error structure. Therefore, when it is neces::;ary to implement multi-objective experimental design. it is common practice to balance out the several optimal design criteria so that each design criterion involved benefits in terms of its relative "high" efficiency. In this study, we proposed several composite design criteria taking the case of heteroscedastic model. WVhen the heteroscedasticity is present in the model. the well known equivalence theorem between 1)- and C-optimality no longer exists and furthermore their design characteristics are sometimes drastically different. We introduced three different design criteria for this purpose: constrained design, combined design, and minimax design criteria. While the first two methods do reflect the prior belief of experimenter, the last one does not take it into account. which is sometimes desirable. Also we extended this method to the case when there are uncertainties concerning the error structure in the model. A simple algorithm and concluslOn follow.On follow.

  • PDF

Multi-Objective Optimization of Steel Structures Using Fuzzy Theory (퍼지 이론을 이용한 강구조물의 다목적 최적설계)

  • Kim, Ki-Wook;Park, Moon-Ho
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.8 no.4
    • /
    • pp.153-163
    • /
    • 2004
  • The main objective of this study is to develop a multi-objective fuzzy optimum design program of steel structures and to verify that the multi-objective fuzzy optimum design is more reasonable than the single objective optimum design in real structural design. In the optimization formulation, the objective functions are both total weight and deflection. The design constraints are derived from the ultimate strength of service ability requirement of AISC-LRFD specification. The structural analysis was performed by the finite element method and also considered geometric non-linearity. The different importance of optimum criteria were reflected with two weighting methods ; membership weighting method and objective weighting method. Thus, designers could choose rational optimum solution of structures with application of two weighting methods.