• Title/Summary/Keyword: engineering and decision-making problems

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공간분석기술을 활용한 사전환경성 검토 GIS 의사결정시스템 개발 (Development of Pre-Environmental Investigation GIS Decision Making System Using Spatial Analysis Technique)

  • 김상석;장용구;강인준
    • 대한토목학회논문집
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    • 제26권1D호
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    • pp.185-193
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    • 2006
  • 현재 시행되고 있는 사전환경성검토는 부분 항목별 수치분석이 이루어지고 있어 종합적인 사전환경성검토가 어려운 실정이다. 또한, 수치자료의 활용이 미흡하여 환경성검토 분석결과의 객관성이 저하되고 있고, 평가비용과 시간도 많이 소요되고 있다. 본 연구에서는 8개 사전환경성 검토요소에 대한 지리정보체계의 공간분석기능을 도입하였으며, 개별 요소들의 평가결과를 통한 종합적인 검토를 수행할 수 있도록 사전 환경성검토 GIS 의사결정시스템을 구축하였다. 본 연구에서 개발한 사전환경성 검토 GIS 의사결정시스템과 기 구축된 GIS 데이터를 활용을 통해 환경성 검토에 객관성이 충족 및 시간 비용 절감이 가능하여 사업초기에 도로 노선선정 시 사전환경성 검토에 활용 가능할 것이다. 또한, 본 연구 개발된 시스템을 통하여 수치적이고 시각적인 자료를 활용한 평가로 주민의 합의를 보다 용이하게 이끌어 낼 수 있고, 사업초기에 비용과 시간을 절감하면서 도로건설에 따른 환경성을 검토할 수 있을 것으로 기대된다.

자동차부품산업에서 공급사슬경영을 위한 공급자 선정.관리 및 주문량 배분에 관한 연구 (Strategic Selection and Management of Suppliers, and Allocation of Order Quantity for Supply Chain Management in Automotive Parts Manufacturers)

  • 장길상;김재균
    • 산업경영시스템학회지
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    • 제32권3호
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    • pp.142-158
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    • 2009
  • The supplier selection problem is perhaps the most important component of the purchasing function. Some of the common and influential criteria in the selection of a supplier include quality, price, delivery, and service. These evaluation criteria often conflict, however, and it is frequently impossible to find a supplier that excels in all areas. In addition, some of the criteria are quantitative and some are qualitative. Thus, a methodology is needed that can capture both subjective and objective evaluation measures. The Analytic Hierarchy Process(AHP) is a decision-making method for ranking alternative courses of action when multiple criteria must be considered. This paper proposes the AHP-based approach which can structure the supplier selection process and the achievements-based procedure which can allocate order quantities for the selected suppliers In automotive part manufacturers. Also, through the practical case of 'D' automotive part manufacturing company, we shows that the proposed AHP based supplier selection approach and the achievements-based allocation procedure of order quantity can be successfully applied for supplier selection and order quantity allocation problems.

A Study of Environmental Management Investment Allocation

  • Tien, Shiaw-Wen;Chang, Ting-Ting;Chung, Yi-Chan;Chen, Ching-Piao;Tsai, Chih-Hung
    • International Journal of Quality Innovation
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    • 제9권2호
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    • pp.57-77
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    • 2008
  • The $21^{st}$ century is a new century of environmental protection. Environmental protection is one of the most important subject matters yet to come. Moreover, as the public pays more attention to environmental problems, enterprises should increase their investment in environmental management. Therefore, determining the investment level for environmental management and allocating the investment to associated environmental management activities has become a major task. The principal and agent theory and sales response functions are used for analysis in this research. The allocation of capital investment in environmental management is found to have significant impact on the aggregate sales response, aggregate profit and investment level. Therefore, in preparing the budget for environmental management, enterprises should focus on investment allocation decisions, determine the investment level and allocation method using integrated means, and apply submarket data in the allocation decision-making process. In other words, in setting the investment level, executive management should take managers' willingness into consideration. In allocating capital investment, managers should identify the optimal allocation method based on submarket characteristics.

Throughput-efficient Online Relay Selection for Dual-hop Cooperative Networks

  • Lin, Yuan;Li, Bowen;Yin, Hao;He, Yuanzhi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권6호
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    • pp.2095-2110
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    • 2015
  • This paper presents a design for a throughput-efficient online relay selection scheme for dual-hop multi-relay cooperative networks. Problems arise with these networks due to unpredictability of the relaying link quality and high time-consumption to probe the dual-hop link. In this paper, we firstly propose a novel probing and relaying protocol, which greatly reduces the overhead of the dual-hop link estimation by leveraging the wireless broadcasting nature of the network. We then formulate an opportunistic relay selection process for the online decision-making, which uses a tradeoff between obtaining more link information to establish better cooperative relaying and minimizing the time cost for dual-hop link estimation to achieve higher throughput. Dynamic programming is used to construct the throughput-optimal control policy for a typically heterogeneous Rayleigh fading environment, and determines which relay to probe and when to transmit the data. Additionally, we extend the main results to mixed Rayleigh/Rician link scenarios, i.e., where one side of the relaying link experiences Rayleigh fading while the other has Rician distribution. Numerical results validate the effectiveness and superiority of our proposed relaying scheme, e.g., it achieves at least 107% throughput gain compared with the state of the art solution.

Improvement in Operation Efficiency for Chip Mounter Using Web Server

  • Lim, Sun-Jong;Joon Lyou
    • International Journal of Precision Engineering and Manufacturing
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    • 제4권6호
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    • pp.5-11
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    • 2003
  • The number of the enterprises which utilize network technology has been increasing for solving problems such as productivity improvement, market trend analysis, and material collection for making decision. Especially, the management of equipment and the recovery time reduction when machines break down are very important factors in productivity improvement of the enterprise. Currently, most of the remote trouble diagnosis of equipment using the internet have just one function of transmitting the trouble information to the user. Therefore it does not directly reflect the user's recovery experience or the developer's new recovery methods. If the user's experienced recovery methods or the developer's recovery methods as well as the basic recovery methods are reflected online or on the internet, it makes it possible to recover faster than before. In this paper, we develop a Remote Monitoring Server (RMS) for chip mounters, and make it possible to reduce the recovery time by reflecting the user's experience and developer's new methods in addition to presenting the basic recovery methods. For this, trouble recovery concept will be defined. Based on this, many functions(trouble diagnosis, the presentation of the basic recovery methods, user's and developer's recovery method, counting function of the trouble number of each code, and presentation of usage number of each recovery methods) were developed. By utilizing the reports of the actual results of chip mounter and the notice function of the parts change time, the rate of operation of the chip mounter can be improved.

A Study on Multi-objective Optimal Power Flow under Contingency using Differential Evolution

  • Mahdad, Belkacem;Srairi, Kamel
    • Journal of Electrical Engineering and Technology
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    • 제8권1호
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    • pp.53-63
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    • 2013
  • To guide the decision making of the expert engineer specialized in power system operation and control; the practical OPF solution should take in consideration the critical situation due to severe loading conditions and fault in power system. Differential Evolution (DE) is one of the best Evolutionary Algorithms (EA) to solve real valued optimization problems. This paper presents simple Differential Evolution (DE) Optimization algorithm to solving multi objective optimal power flow (OPF) in the power system with shunt FACTS devices considering voltage deviation, power losses, and power flow branch. The proposed approach is examined and tested on the standard IEEE-30Bus power system test with different objective functions at critical situations. In addition, the non smooth cost function due to the effect of valve point has been considered within the second practical network test (13 generating units). The simulation results are compared with those by the other recent techniques. From the different case studies, it is observed that the results demonstrate the potential of the proposed approach and show clearly its effectiveness to solve practical OPF under contingent operation states.

Shipyard Spatial Scheduling Solution using Genetic Algorithms

  • Yoon Duck Young;Ranjan Varghese
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2004년도 학술대회지
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    • pp.35-39
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    • 2004
  • In a shipyard, there exist various critical decision making components pertaining to various production hindrances. The most prominent one is best-fit spatial arrangement for the minimal spatial occupancy with better pick-ability for the erection of the ship in the dock. During the present research, a concept have been conceived to evade the gap between the identification oj inter-relationships among a set of blocks to be included on a pre-erection area, and a detailed graphical layout of their positions, is called an Optimal Block Relationship Diagram A research has been performed on generation of optimal (or near Optimal) that is, with minimal scrap area. An effort has been made in the generation of optimal (or near-optimal) Optimal Block Relationship Diagram with the Goldberg's Genetic Algorithms with a representation and a set of operators are 'trained' specifically for this application. The expected result to date predicts very good solutions to test problems involving innumerable different blocks to place. The suggested algorithm could accept input from an erection sequence generator program which assists the user in defining the nature and strength of the relationships among blocks, and could produce input suitable for use in a detailed layout stage.

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시뮬레이션과 DEA를 이용한 열차도장시설의 인력배치방안 연구 (The Manpower Assignment Design of the Train Paint Process with the Simulation and DEA Methods)

  • 조현섭;김연진;이홍철
    • 한국산학기술학회논문지
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    • 제10권6호
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    • pp.1389-1398
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    • 2009
  • 본 연구에서는 현재 설계단계에 있는 대전 철도 차량 검수시설 중 도장장에 대한 시뮬레이션 모델링과 DEA기법을 이용하여 작업에 필요한 최적 인력배치방안을 연구하였다. 이를 위해 먼저, 열차 대기시간과 처리량, 그리고 주요설비의 가동률 등을 주요 반응변수로 선정하여 시스템을 시뮬레이션 하였다. 그 후 인력배치 정책과 작업인원수 및 숙련공비율 등의 다양한 의사결정요소들로 설계된 대안들을 DEA기법을 사용하여 필요인력과 그 배치방안을 설계하였다. 총 27개의 대안들 중 기술 및 규모의 효율성(SE)을 모두 만족시키는 4개의 최종 대안을 선정하였으며, 이를 의사결정자들에게 제시하고 인력수급 및 조직개편과 연계하여 추후 운영설계 시 고려하도록 하였다. 이러한 절차를 통해 신규시설 건설시 의사결정자들이 고려해야하는 다양한 요소들을 과학적인 절차를 통해 해결할 수 있는 연구방법을 제시하였다.

가중연관규칙 탐사를 이용한 재활훈련운동과 근육 활성의 연관성 분석 (Analysis on Relation between Rehabilitation Training Movement and Muscle Activation using Weighted Association Rule Discovery)

  • 이아름;박용군;권대규;김정자
    • 전자공학회논문지CI
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    • 제46권6호
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    • pp.7-17
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    • 2009
  • 효과적인 재활 시스템을 구상하는데 있어서 훈련 데이터의 정교한 분석은 다음 단계 훈련을 위한 피드백 자료로서 매우 중요하다. 현재 다양한 생체 역학적 실험을 통해 인간의 운동 능력을 평가하고 이로부터 생성된 데이터의 분석을 위한 객관적이고 신뢰성 있는 연구결과들이 발표되고 있다. 그러나 대부분의 기존 연구들은 기초 통계적인 방법에 근거한 정량분석만을 수행함으로써, 획득된 정보를 임상에 적용 하는데 있어서는 충분한 신뢰성을 보장할 수 없다. 데이터마이닝은 대용량 데이터에 들어있는 숨겨진 규칙과 패턴을 탐사함으로써 임상 데이터에 숨어있는 의미 있는 정보추출에 성공적으로 사용되고 있으며, 특히 임상 연구 분야에서는 훌륭한 의사 결정 지원 시스템으로서 점점 그 사용이 증가되고 있다. 본 연구에서는 신뢰성 있는 자세 제어 능력(Postural control ability) 평가를 위해서 측정된 훈련 데이터에 가중연관규칙 탐사를 적용하여 자세 훈련 유형에 따른 근육 활성 패턴과의 연관성을 분석, 효율적인 재활 훈련 규칙을 탐사하였다. 탐사된 규칙은 재활 및 임상 전문가의 의사결정에 더욱 정성적이고 유용한 선험적 지식으로 사용 될 수 있으며, 이를 근거로 환자 맞춤형 최적의 재활 훈련 모델을 구상하기 위한 지표로서 사용될 수 있다.

EXPLORING THE CHALLENGES TO USAGE OF BUILDING CONSTURCTION COST INDICES GHANA

  • Osei-Tutu, E;Adobor, C.D;Kissi, E.;Osei-Tutu, S.;Adjei-Kumi, T.
    • 국제학술발표논문집
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    • The 7th International Conference on Construction Engineering and Project Management Summit Forum on Sustainable Construction and Management
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    • pp.313-320
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    • 2017
  • Price fluctuation contract is imperative and of paramount essence in the construction industry as it provides adequate relief and cushioning for changes in the prices of input resources during construction. As a result, several methods have been devised to better help in arriving at fair recompense in the event of price chang es. However, stakeholders often appear not to be satisfied with the existing methods of fluctuation evaluation, ostensibly because of the challenges associated with them. The aim of this study was to identify the challenges to usage of building construction cost indices in Ghana. Data was gathered from contractors and quantity surveying firms. The study utilized survey questionnaire approach to elicit responses from the contractors and the consultants. Data gathered was analyzed scientifically, using the Relative Importance Index (RII) to rank the problems associated with the existing methods. The findings revealed the following among others; late release of data; inadequate recovery of costs; and work items of interest not included in the published indices as the main challenges of the existing methods. This study will provide useful lessons for policy makers and practitioners in decision making towards the usage and improvement of available indices.

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