• 제목/요약/키워드: MCDA

검색결과 25건 처리시간 0.019초

An Integrated Approach to Measuring Supply Chain Performance

  • Theeranuphattana, Adisak;Tang, John C.S.;Khang, Do Ba
    • Industrial Engineering and Management Systems
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    • 제11권1호
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    • pp.54-69
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    • 2012
  • Chan and Qi (SCM 8/3 (2003) 209) developed an innovative measurement method that aggregates performance measures in a supply chain into an overall performance index. The method is useful and makes a significant contribution to supply chain management. Nevertheless, it can be cumbersome in computation due to its highly complex algorithmic fuzzy model. In aggregating the performance information, weights used by Chan and Qi-which aim to address the imprecision of human judgments-are incompatible with weights in additive models. Furthermore, the default assumption of linearity of its scoring procedure could lead to an inaccurate assessment of the overall performance. This paper addresses these limitations by developing an alternative measurement that takes care of the above. This research integrates three different approaches to multiple criteria decision analysis (MCDA)-the multiattribute value theory (MAVT), the swing weighting method and the eigenvector procedure-to develop a comprehensive assessment of supply chain performance. One case study is presented to demonstrate the measurement of the proposed method. The performance model used in the case study relies on the Supply Chain Operations Reference (SCOR) model level 1. With this measurement method, supply chain managers can easily benchmark the performance of the whole system, and then analyze the effectiveness and efficiency of the supply chain.

Sequential optimization for pressure management in water distribution networks

  • Malvin S. Marlim;Doosun Kang
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2023년도 학술발표회
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    • pp.169-169
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    • 2023
  • Most distributed water is not used effectively due to water loss occurring in pipe networks. These water losses are caused by leakage, typically due to high water pressure to ensure adequate water supply. High water pressure can cause the pipe to burst or develop leaks over time, particularly in an aging network. In order to reduce the amount of leakage and ensure proper water distribution, it is important to apply pressure management. Pressure management aims to maintain a steady and uniform pressure level throughout the network, which can be achieved through various operational schemes. The schemes include: (1) installing a variable speed pump (VSP), (2) introducing district metered area (DMA), and (3) operating pressure-reducing valves (PRV). Applying these approaches requires consideration of various hydraulic, economic, and environmental aspects. Due to the different functions of these approaches and related components, an all-together optimization of these schemes is a complicated task. In order to reduce the optimization complexity, this study recommends a sequential optimization method. With three network operation schemes considered (i.e., VSP, DMA, and PRV), the method explores all the possible combinations of pressure management paths. Through sequential optimization, the best pressure management path can be determined using a multiple-criteria decision analysis (MCDA) to weigh in factors of cost savings, investment, pressure uniformity, and CO2 emissions. Additionally, the contribution of each scheme to pressure management was also described in the application results.

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Effect of critical flow model in MARS-KS code on uncertainty quantification of large break Loss of coolant accident (LBLOCA)

  • Lee, Ilsuk;Oh, Deogyeon;Bang, Youngseog;Kim, Yongchan
    • Nuclear Engineering and Technology
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    • 제52권4호
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    • pp.755-763
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    • 2020
  • The critical flow phenomenon has been studied because of its significant effect for design basis accidents in nuclear power plants. Transition points from thermal non-equilibrium to equilibrium are different according to the geometric effect on the critical flow. This study evaluates the uncertainty parameters of the critical flow model for analysis of DBA (Design Basis Accident) with the MARS-KS (Multi-dimensional Analysis for Reactor Safety-KINS Standard) code used as an independent regulatory assessment. The uncertainty of the critical flow model is represented by three parameters including the thermal non-equilibrium factor, discharge coefficient, and length to diameter (L/D) ratio, and their ranges are determined using large-scale Marviken test data. The uncertainty range of the thermal non-equilibrium factor is updated by the MCDA (Model Calibration through Data Assimilation) method. The updated uncertainty range is confirmed using an LBLOCA (Large Break Loss of Coolant Accident) experiment in the LOFT (Loss of Fluid Test) facility. The uncertainty ranges are also used to calculate an LBLOCA of the APR (Advanced Power Reactor) 1400 NPP (Nuclear Power Plants), focusing on the effect of the PCT (Peak Cladding Temperature). The results reveal that break flow is strongly dependent on the degree of the thermal non-equilibrium state in a ruptured pipe with a small L/D ratio. Moreover, this study provides the method to handle the thermal non-equilibrium factor, discharge coefficient, and length to diameter (L/D) ratio in the system code.

AHP와 TOPSIS 융합 방법론을 이용한 국가 사이버 역량 강화 방안 (The Enhancement Strategy on National Cyber Capability Using Hybrid Methodology of AHP and TOPSIS)

  • 배선하;박상돈;김소정
    • 융합보안논문지
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    • 제15권4호
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    • pp.43-55
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    • 2015
  • ICT가 사회 주요 기반 구조로 자리매김 함에 따라 사이버 역량 강화 필요성이 대두되고 있다. 그러나 국내에 효과적인 사이버 역량 평가 방법론이 존재하지 않아 우리나라의 사이버 역량을 평가하고, 이에 기반한 역량 강화 방안 마련이 어려운 실정이다. 사이버 역량 평가는 우리의 사이버 역량 실태를 점검하여 정책 방향 수립에 활용하고 효과적인 예산 편성을 위한 근간을 제공할 수 있다. 그러나 현실적으로 사이버 역량 평가 항목이 다양하고, 각 항목의 판단 척도가 상이하여 의사 결정자가 판단하는데 어려움이 존재한다. 이에 본 논문에서는 AHP와 TOPSIS를 융합한 사이버 역량 평가 방법론을 제안하였다. AHP는 다양한 평가 항목간의 중요도 판별에 활용하고, TOPSIS는 평가 대상국 간의 순위 판별에 활용하였고, 가상 실험 데이터를 이용하여 주요 4개국에 대한 평가를 수행하였다. 실험 결과 제안한 사이버 평가 방법론은 AHP를 이용한 사이버 평가에 비해 평가 항목과 평가 대상국의 확장이 가능하고, 보다 정교한 수학적 기반을 통해 객관적인 평가가 가능한 것으로 나타났다.

Evaluation of Suitable REDD+ Sites Based on Multiple-Criteria Decision Analysis (MCDA): A Case Study of Myanmar

  • Park, Jeongmook;Sim, Woodam;Lee, Jungsoo
    • Journal of Forest and Environmental Science
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    • 제34권6호
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    • pp.461-471
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    • 2018
  • In this study, the deforestation and forest degradation areas have been obtained in Myanmar using a land cover lamp (LCM) and a tree cover map (TCM) to get the $CO_2$ potential reduction and the strength of occurrence was evaluated by using the geostatistical technique. By applying a multiple criteria decision-making method to the regions having high strength of occurrence for the $CO_2$ potential reduction for the deforestation and forest degradation areas, the priority was selected for candidate lands for REDD+ project. The areas of deforestation and forest degradation were 609,690ha and 43,515ha each from 2010 to 2015. By township, Mong Kung had the highest among the area of deforestation with 3,069ha while Thlangtlang had the highest in the area of forest degradation with 9,213 ha. The number of $CO_2$ potential reduction hotspot areas among the deforestation areas was 15, taking up the $CO_2$ potential reduction of 192,000 ton in average, which is 6 times higher than that of all target areas. Especially, the township of Hsipaw inside the Shan region had a $CO_2$ potential reduction of about 772,000 tons, the largest reduction potential among the hotpot areas. There were many $CO_2$ potential reduction hot spot areas among the forest degradation area in the eastern part of the target region and has the $CO_2$ potential reduction of 1,164,000 tons, which was 27 times higher than that of the total area. AHP importance analysis showed that the topographic characteristic was 0.41 (0.40 for height from surface, 0.29 for the slope and 0.31 for the distance from water area) while the geographical characteristic was 0.59 (0.56 for the distance from road, 0.56 for the distance from settlement area and 0.19 for the distance from Capital). Yawunghwe, Kalaw, and Hsi Hseng were selected as the preferred locations for the REDD+ candidate region for the deforestation area while Einme, Tiddim, and Falam were selected as the preferred locations for the forest degradation area.