• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6D
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• pp.761-770
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• 2009

The energy efficiency and environment-friendly aspect of the railway system would be superior to other on-land ransportation systems. In a preliminary feasibility study stage and selection of optimal railway route, the energy efficiency and problems related to environment are usually considered. For the selection of optimal railway route, geographical features and facility of management are generally considered. Environment effect factors for the selection of environment-friendly railway router are focused and studied in this paper. In this study, various analysis of opinion of specialists (railway, environment, transport, urban planning, survey) and the guideline for construction of environment-friendly railway were accomplished. From these results of various analysis, 7 major categories (topography/geology, flora and fauna, Nature Property, air quality, water quality, noise/vibration, visual impact/cultural assets) were extracted. To select environment friendly railway route, many alternatives should be compared optimal route must be selected by a comprehensive assessment considering these 7 categories. To solve this problem, the selected method was AHP which simplifies the complex problems utilizing hierarchy, quantifying qualitative problems through 1:1 comparison, and extracting objective conclusions by maintaining consistency. As a result, a GUIbased program was developed which provides basic values of weighted parameters of each category defined by specialists, and a quantification of detailed assessment guidelines to ensures consistency.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1389-1398
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• 2009

This research suggests the calculation and analytic method of determining the proper numbers of manual workers with simulation and DEA methods. For this, first of all we designed and analysed the simulation model of real facility being built in Dea-Jun. Secondly, we find the solution with DEA among various alternatives built based on the results of the simulation analysis. In the simulation process, the waiting time, the number of painted trains, and utilization of main equipment are considered as main response variables. After simulation, we built DMUs(Decision Making Unit) consisting of combined results with the manpower assignment policies, the numbers of workers, and the rate of skilled operators, and calculated the efficiency of DMUs with the DEA method. Among 27 DMUs, 4 DMUs turned out efficient technically and on scale. In conclusion, through the suggested procedure, this research shows the way that decision makers can solve the problems with various factors they should concern, along the scientific process, when building a new facility.

• Land and Housing Review
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• v.5 no.4
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• pp.297-303
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• 2014

Recently, block and permeable pavements have been placed in apartment complex. However. it is hard to decide the cycle of maintenance and repair due to lack of performance evaluation criteria for these pavements. This study carried out life cycle cost analysis(LCCA) to present resonable alternatives of the pavements by considering initial construction cost, maintenance and repair cost along with the cycle of repair. According to results of LCCA, the interlocking concrete block pavement is the best alternative when the repair cycle of 20years is assumed, while asphalt concrete pavement is the best alterative when the repair cycle of 10years is assumed. Therefore, the repair cycle is most important factor to select alternative. Also, it is necessary to develop resonable performance evaluation index to quantify the cycle of maintenance and repair in the future.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.3
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• pp.255-266
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• 2009

In this study, a robust aerospace system design process for the aerospace system is developed by considering the uncertainties of user requirements, manufacturing errors, and operational environment variation. User requirements are analyzed and quantified by decision making models and system engineering methods to select alternative concepts which satisfies the various requirements. Robust design and optimization method is applied to derive the robust solution of the selected system. First, a variance of objective function is calculated, and a mean value and a variance of target value are determined by the deterministic design optimization results of the system. A robust optimum design formulation is then needed to derive the robust solution that minimizes the variance of the response and moves the mean values to the target value. It is applied to Very Light Jet (VLJ) aircraft to which much attention is paid recently in civil aerospace market.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.1
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• pp.117-124
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• 2010

Different to other social infrastructures, bridge elements or bridges can be damaged or collapsed and this may cause death toll and severe social and economical damage, bridges should be managed to maintain a safety level. Diverse strengthening methods is developed to improve a deteriorated bridge performance up to original design level. But rational decision-making process and methodologies to select a optimum strengthening method are absence yet in Korea. This paper therefore derived items and proposed methodologies for quantity estimate considering uncertainty to select a optimum strengthening method among conceptually designed alternatives. And also, to demonstrate the applicability and verification of the proposed approach, it was applied to select the optimum strengthening method for the deteriorated T-shape concrete girder bridge. The model and the procedure can greatly contribute to the uncertainty-oriented alternative selection.

• Journal of Korean Society of Transportation
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• v.23 no.7 s.85
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• pp.87-98
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• 2005

Through rail transit has many merits as a safe, environmental harmonic and scheduled transit, there are many problems to construct railroads because of the public resentment. However, there is no reasonable way to settle the conflict properly and it causes enormous social and economic losses. This paper suggests a methodology to evaluate public complaint using the AHP technique, which is generally used as the methodology to evaluate public complaint using the AHP technique, which is generally used as the Multi-Criteria Decision Making (MCDM). However, the result from the AHP has some defects to control conflicts because the interests related to railroad projects are so complex that it is hard to make people persuaded easily. Therefore, this paper suggests 'the improvement ranking method', 'the sensitive analysis', and 'the assessment of independence relationship' which can aid the basic AHP to be robust. And the AHP. modified by fuzzy method, is also suggested to apply this methodology to example rail paths in Korea.

• Journal of Korean Society of Transportation
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• v.31 no.5
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• pp.3-15
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• 2013

The purpose of this study is to propose a methodology for operating variable speed limit (VSL) strategies in freeway work zones. A notable feature in this study is to incorporate a multi-criteria decision making process into deriving better VSL strategies. Decision criteria in this study include operational efficiency, safety, and environmental impacts. Travel speed, acceleration noise, and CO2 were used as performance measures for evaluating VSL strategies. A multi-criteria value function was developed through an analytical hierarchical process (AHP) for representing expert's knowledge. Then, a variety of VSL operations scenarios were investigated utilizing a microscopic traffic simulation suite, VISSIM. The proposed methodology would be useful in supporting more efficient, safer, and more environment-friendly traffic operations and control in freeway work zones.

• The Korean Journal of Financial Studies
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• v.4 no.1
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• pp.205-232
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• 1998

본 연구는 최근의 제도개선으로 그 중요성이 증대되고 있는 상대가치계산 방식의 대안으로서 주가수익가치평가방식(Price-Earnings Valuation:이하 'P/E방식'이라 한다)을 우리 나라 시장에 적용하고 그 정확성을 검증한다. P/E방식에 따른 기업의 주가는 당해 기업의 주당수익과 유사기업으로부터 산출된 적정 주가수익비율(P/E 배수)을 곱함으로서 결정된다. 1988년에 우리 나라 시장에 상장된 기업을 대상으로 P/E방식을 사용한 연구결과는 두가지측면에서 중요한 시사점을 제공하고 있다. 첫째, 유사기업 선정시 현행 표준산업분류표보다는 주당수익 혹은 주당경상이익을 선정기준으로 사용했을 때 예측오차가 훨씬 줄어들고 있음을 보여주고 있다. 둘째, 비교기준가격산정시점이 상장시점에 근접할수록 예측오차는 더 적음을 보여주고 있다. 특히 P/E방식을 사용할 때 유사기업선정기준에 대한 본 연구의 결과는 금융선진국을 중심으로 한 선행연구결과와 일치하지 않고 있으며[Alford(1992), Kahle and Walkling(1996)], 우리 나라 공모주의 가격산정 및 기존 상장주식의 향후 비교가치 평가시에 반드시 고려될 필요가 있다고 본다.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11b
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• pp.385-387
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• 2005

복잡하고 방대해진 시스템 개발에서 다양한 이해 관계자들의 요구사항을 시스템에 정확히 반영해야 하고, 이를 위해 시스템의 품질 속성과 이해관계자들의 이해관계를 반영한 소프트웨어 아키텍처의 설계가 성공적인 프로젝트를 위한 중요한 이슈가 되었다. 본 연구에서는 아키텍처 설계 과정에서 식별된 아키텍처 접근법 대안들에 대해 시스템의 요구사항에 대한 만족도를 평가하여 설계단계에서 설계자들이 가장 적합한 아키텍처 접근법을 선정 하도록 하고 있다. 즉 평가를 통해 선정된 아키텍처 접근법을 기반으로 아키텍처 설계를 확장해 나감으로써 설계 산출물의 신뢰성과 완성도를 높이는 효과를 기대 할 수 있다.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.1061-1066
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• 1995

우리나라의 후행 원전연료주기 정책은 경제성이나, 기술성, 환경 영향 등 여러가지 계량, 비계량 지표들을 면밀히 분석하여 궁극적으로 국민의 복지와 민족의 번영에 이바지 할 수 있도록 선정되어야 한다. 본 논문에서는 AHP(Analytic Hierarchy Process) 방법을 후행 원전연료주기 정책 수립에 이용할 수 있도록 우리나라에서 가능한 후행 원전연료주기 시나리오의 몇가지 예를 제시하였으며, 정책 결정요소로서 에너지 안보와 경제성, 기술성, 국내 사회정치, 국제관계 등 5개의 주기준과 주기준에 종속되는 19개의 보조기준을 선정하였는데, 적절한 후행 원전연료주기 정책대안들을 선정하여 AHP 방법에 따라 정책결정기준들을 평가한다면 후행 원전연료주기 정책수립과정에 AHP 방법을 효과적으로 이용할 수 있을 것으로 기대된다.