• Title/Summary/Keyword: Multi-Objective function

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A Study on Weight of Consideration Factors in Layout Development for Machinery Industries using Improvemant-type Heuristics (개선형 탐색법에 의한 기계공장 배치안 작성시 고려요소별 가중치의 크기에 관한 연구)

  • Moon, Gee-Ju
    • Journal of the Korean Operations Research and Management Science Society
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    • v.20 no.2
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    • pp.109-123
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    • 1995
  • Weight of the factors to be considered in layout development with improvement-type heuristics is discussed in this paper. Determination of weight is especially important if it is designed to be used with an improvement-type heuristic. It is same as the value of variable coefficients in a multi-objective function as well as indices for departmental switching orders in the heuristic. Various weights are examined through computer simulation to verify whether the numerical values collected from machinery industries can be used as weights. And then a method to be used for searching an optimum or optimum-tending layout for machinery industries is presented using the weight.

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Optimum Design of Axial-Flow Fans Including Noise Parameters (소음파라메터를 고려한 축류송풍기의 최적설계)

  • Son, B.J.;Lee, S.H.;Yoon, S.J.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.7 no.1
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    • pp.1-12
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    • 1995
  • In order to seek various relationships among many design parameters employed in the design of the axial-flow fans the program which generates acoustic spectrum has been developed and its validity verified. Outputs of the program, with other outputs from a formerly developed performance prediction program, have been used to form a multi-objective function, for which an optimal design process was carried out. The present analysis shows that overall noise level and efficiency has contrasting trends, and the chord length turns out to be the most critical design variable. In the chosen design case of requirements $Q=2000m^2/min$, ${\Delta}P_s=67mmAq$, D=1.4m, the chord length of 0.2059m minimizes the overall noise level, while chord length of 0.1254m maximizes the efficiency. The resulting chord length in the balanced optimization is 0.1809m.

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Approximate Dynamic Programming Strategies and Their Applicability for Process Control: A Review and Future Directions

  • Lee, Jong-Min;Lee, Jay H.
    • International Journal of Control, Automation, and Systems
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    • v.2 no.3
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    • pp.263-278
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    • 2004
  • This paper reviews dynamic programming (DP), surveys approximate solution methods for it, and considers their applicability to process control problems. Reinforcement Learning (RL) and Neuro-Dynamic Programming (NDP), which can be viewed as approximate DP techniques, are already established techniques for solving difficult multi-stage decision problems in the fields of operations research, computer science, and robotics. Owing to the significant disparity of problem formulations and objective, however, the algorithms and techniques available from these fields are not directly applicable to process control problems, and reformulations based on accurate understanding of these techniques are needed. We categorize the currently available approximate solution techniques fur dynamic programming and identify those most suitable for process control problems. Several open issues are also identified and discussed.

Multi-Objective Soft Computing-Based Approaches to Optimize Inventory-Queuing-Pricing Problem under Fuzzy Considerations

  • Alinezhad, Alireza;Mahmoudi, Amin;Hajipour, Vahid
    • Industrial Engineering and Management Systems
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    • v.15 no.4
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    • pp.354-363
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    • 2016
  • Due to uncertain environment, various parameters such as price, queuing length, warranty, and so on influence on inventory models. In this paper, an inventory-queuing-pricing problem with continuous review inventory control policy and batch arrival queuing approach, is presented. To best of our knowledge, (I) demand function is stochastic and price dependent; (II) due to the uncertainty in real-world situations, a fuzzy programming approach is applied. Therefore, the presented model with goal of maximizing total profit of system analyzes the price and order quantity decision variables. Since the proposed model belongs to NP-hard problems, Pareto-based approaches based on non-dominated ranking and sorting genetic algorithm are proposed and justified to solve the model. Several numerical illustrations are generated to demonstrate the model validity and algorithms performance. The results showed the applicability and robustness of the proposed soft-computing-based approaches to analyze the problem.

Evolving swarm of UAVs

  • Chi, T.Z.;Cheng, Hayong;Page, J.R.;Ahmed, N.A.
    • Advances in aircraft and spacecraft science
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    • v.1 no.2
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    • pp.219-232
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    • 2014
  • This paper reports on an ongoing study investigating the feasibility of using an evolutionary method to develop the rules governing Self-Organised (SO) systems for use in swarms of unmanned aerial vehicles. In general, it is difficult to design swarm systems that follow explicit global behaviour. Unlike optimising a predefined objective function, the solution to the problem is the emergent behaviour in the SO systems which results from simultaneous interactions among agents and between agents and their environment. In this study, evolutionary algorithms are used to investigate their control and effectiveness in synthesising the weighting of different rules on SO emergent behaviour. Both homogeneous swarms and heterogeneous swarms were considered though the results provided are for a case study investigating the simplest problem a homogeneous swarm without mutation. Though simple this study does indicate the potential of the approach.

A study on the analysis of Korean eco-housing in Bang chon village (방촌마을의 생태주거단지 계획 분석에 관한 연구)

  • Choi, Yool
    • KIEAE Journal
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    • v.2 no.1
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    • pp.33-40
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    • 2002
  • The objective of this study is to interpret a typical Korean traditional settlement for searching for planning criteria of ecological friendly housing estates. The interpreting framework is five environmental ecological ideas as the adaptation to the exterior of village, the eco-space in village, the interior of house, the cycling of material and the reasonable energy system, prevention of environment pollution and reduction of wastes. Through the interpretation, it has been found out that Bang chon village has been developed to an environmental ecological rational setting and has the meaningful elements for environmental friendly housing estates. Particularly, the spatial components of Bang-chon are characterized by the concept of multi-function, and diversity, which are worth of being considered as important planning of ecological friendly housing estates.

An Optimization Method of Series Condenser for Improvement of Transient Stability (과도안정도 향상을 위한 직렬콘덴서의 최적화 방안)

  • You, Seok-Ku;Moon, Byoung-Seo;Kim, Kyu-Ho
    • Proceedings of the KIEE Conference
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    • 1996.07b
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    • pp.890-892
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    • 1996
  • This paper presents a method for optimal placement of series condenser in order to improve the power system transient stability using genetic algorithms(GAs). In applying GAs, this approach utilizes two kinds of strings, one is coded by a binary finite-length for the selection of lines to install series condenser, the other is coded by a real value for the determination of injected condenser capacitance. For the formulation. this paper considers multi-objective function which is the critical energy as decelerating energy in power systems and the total injected condenser capacitance. The proposed method is applied to 9-bus, 18-line, 3-machine model system to show its effectiveness in determining the locations to install series condenser and the series condenser capacitance to be injected, simultaneously.

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Analysis and Reduction of Escalator Vibration Using the Response Surface Methodology (반응 표면법을 이용한 에스컬레이터의 진동 저감에 관한 연구)

  • Lim, Su-Young;Kwon, Yi-Sug;Park, Chan-Jong;Hong, Seong-Wook
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.623-628
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    • 2000
  • This paper deals with an analysis and reduction of escalator vibration by using the response surface model. Optimization of the escalator vibration is performed by minimization of the vibration responses which are measured at steps. The response surface models of the factors are constructed by using the experimental data based on the D optimal design method. The multi-objective optimization is also performed by applying desirability function and overlaid contour plot techniques. The optimal solution, which is obtained for a typical escalator system, is applied to reduce the escalator vibration.

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A Rational Operation Scheduling for Operating Cost Saving in Cogeneration System for Paper Mill (제지공장용 열병합발전시스템의 운용비용절감을 위한 합리적 운전계획수립에 관한 연구)

  • 최광범;이종범
    • Journal of Energy Engineering
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    • v.8 no.4
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    • pp.512-518
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    • 1999
  • This paper proposed the optimal operational scheduling of cogeneration system for paper mill connected with several auxiliary devices Auxiliary devices that include auxiliary boilers, waste heat boilers and sludge uncinerators operate with multi-cogeneration systems. Especially environment element was considered in objective function to solve environment problem. Electricity can be purchased through power system from utility. The proposed operational strategy on cogeneration system for paper mill to increase energy efficiency can be applied to the similar cogeneration system is industrial field.

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-Machining Route Selection with the Shop Flow Information Using Genetic Algorithm- (작업장 특성을 고려한 가공경로선정 문제의 유전알고리즘 접근)

  • 이규용;문치웅;김재균
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.23 no.54
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    • pp.13-26
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    • 2000
  • Machining route selection to produce parts should be based on shop flow information because of input data at scheduling tasks and is one of the main problem in process planning. This paper addresses the problem of machining route selection in multi-stage process with machine group included a similar function. The model proposed is formulated as 0-1 integer programing considering the relation of parts and machine table size, avaliable time of each machine for planning period, and delivery date. The objective of the model is to minimize the sum of processing, transportation, and setup time for all parts. Genetic algorithm approach is developed to solve this model. The efficiency of the approach is examined in comparison with the method of branch and bound technique for the same problem. Also, this paper is to solve large problem scale and provide it if the multiple machining routes are existed an optimal solution.

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