• 대한토목학회논문집
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• 제31권3D호
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• pp.383-389
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• 2011

본 연구는 교통기본법(안)에 명시된 대중교통 사각지대 설정과 평가를 위한 3가지 평가척도를 제시하였다. 평가척도는 행정동 단위의 대중교통 노선 및 운행실태에 대한 기초 DB를 적용하여 대중교통 서비스권역, 대중교통 배차간격, 1일 총 운행시간을 각각 A-F(6등급)으로 구분하였다. 대중교통 사각지대 평가척도는 정부 및 지자체에서 대중교통 서비스 낙후지역의 최저 대중교통 공급 및 연계노선 계획, 최저배차계획, 1일 대중교통 총 운행시간 계획에 기준으로 활용할 수 있을 것이다.

• Industrial Engineering and Management Systems
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• 제15권4호
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• pp.374-384
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• 2016

The efficiency of a supply chain can be extremely affected by its design which includes determining the flow pattern of material from suppliers to costumers, selecting the suppliers, and defining the opened facilities in network. In this paper, a multi-objective multi-echelon multi-product supply chain design model is proposed in which several suppliers, several manufacturers, several distribution centers as different stages of supply chain cooperate with each other to satisfy various costumers' demands. The multi-objectives of this model which considered simultaneously are 1-minimize the total cost of supply chain including production cost, transportation cost, shortage cost, and costs of opening a facility, 2-minimize the transportation time from suppliers to costumers, and 3-maximize the service level of the system by minimizing the maximum level of shortages. To configure this model a graph theoretic approach is used by considering channels among each two facilities as links and each facility as the nodes in this configuration. Based on complexity of the proposed model a multi-objective Pareto-based vibration damping optimization (VDO) algorithm is applied to solve the model and finally non-dominated sorting genetic algorithm (NSGA-II) is also applied to evaluate the performance of MOVDO. The results indicated the effectiveness of the proposed MOVDO to solve the model.

• 한국수소및신에너지학회논문집
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• 제33권3호
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• pp.183-201
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• 2022

In this study, economic feasibility analysis was performed when various hydrogen production and transport technologies were applied to derive hydrogen supply plans by period. The cost of hydrogen may vary depending on several reasons; configuration of the entire cycle supply path from production, storage/transportation, and utilization to the cost that can be supplied to consumers. In this analysis, the hydrogen supply price according to the hydrogen supply route configuration for each period was analyzed for the transportation hydrogen demand in metropolitan area, where the demand for hydrogen is expected to be the highest due to the expansion of hydrogen supply.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1571-1572
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• 2015

기존 궤도특수차는 디젤유를 사용하기 때문에 도시철도 지하환경을 오염시키고 유해한 배기가스가 인체에 악영향을 준다. 따라서 경제성이 우수한 친환경적인 하이브리드형 궤도특수차를 개발하기 위해 이에 따른 궤도특수차의 주행동력장치에 대한 설계조건을 규명하고자 한다.

• 디지털융복합연구
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• 제12권11호
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• pp.289-298
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• 2014

최근 들어, 보다 효율적이고 경제성을 갖춘 전기자동차 기술이 등장함에 따라 철도의 전통적인 기술적 패러다임이 변화하고 있다. 오래전에 제안되었지만 이상적인 개념으로 평가받던 수요응답형 순환교통(PRT) 시스템의 경우에도 전기자동차 플랫폼의 활용을 통해서 실현 가능성을 높여가고 있다. 특히, 배터리에 의해 구동되는 차량의 경우 안정적이고 효율적인 운영의 측면에서 기술적인 어려움에 직면하고 있다. 그렇지만, 무선 급전에 의한 급속충전 기술과 고에너지 밀도의 슈퍼커패시터 적용은 이러한 기술적인 난제를 극복하고 도시 미관의 향상을 통해서 전기 에너지를 기반으로 한 신교통수단의 보급을 증대하는데 기여할 것으로 생각된다. 본 논문에서는 한국형 PRT 차량의 전력공급 시스템의 설계, 에너지 소모량 및 장치의 성능 해석과 하드웨어 제작 및 시험에 이르는 일련의 개발과정에 대해서 논한다. 그 결과, 테스트베드에서의 전력공급 모듈의 시험평가 결과가 요구하는 성능에 부합하는 것으로 확인되었다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2006년도 추계학술대회
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• pp.661-664
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• 2006

Under a VMI (Vendor Managed Inventory) system, the vendor holds a certain level of control over not only inbound replenishment decisions on stocking but also outbound re-supply decisions. In this situation, vendor faces a better opportunity to synchronize the inventory and transportation decisions. However, shipment consolidation can reduce transportation expenses, but delivery time about the customer comes to be long and a customer service is fallen. Thus, a stock and transportation decision must consider this correlation. This study look into the relevant literature and suggest about further research direction.

• 경영과학
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• 제25권2호
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• pp.89-109
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• 2008

As the importance of logistics is increasing, Enterprises try to design the supply chain(SC) network to minimize the total costs considering inventory holding cost, transportation cost and apply the efficient strategies of supply chain based on SC network. Despite of this efforts, Calculating the logistics costs without reflecting the real components of logistics like the packaging cost, transportation related cost, storage cost, loading & unloading cost, and distribution costs, the companies has many limitation to calculate the logistics cost of real enterprise. For overcoming such problem, this paper is aimed at establishing SC strategies which can be an efficient alternative for a decision making on supply chain, based on existing reference and current logistics networks of 'L' company in Korea. Also, we analyze the interaction effects between strategies as well as install the optimal SC network reflecting concrete logistics components from the viewpoint of total logistics costs using the simulation and statistic methods. we expect that analysis results of this paper would be applied various industries and be utilized to the efficient tools for the decision making by planing and execution of the logistics budget from enterprises.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.411-414
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• 2015

The purpose of this study is to conduct a comparative analysis between Korea and the United States of the supply process of unit modular housing at both the factory production phase and the transportation and lifting phase, as part of an attempt to invigorate the unit modular housing market in Korea. Unlike the practice in the United States, one of Korea's unique characteristics is that the floor is constructed with reinforced concrete and hot water heating system. To do this, the wet method in Korea is used that includes concrete placement, curing and constructing hot water floor heating system at the factory production phase, which results in a longer production time and also requires the lifting of heavier loads. In the United States, interior and exterior finishing works of modular housing are performed by different companies, and the distance between the unit module factory and the construction site is quite far. This kind of dualized production structure may cause confusion when it comes to schedule management, procurement management, and stock management. Moreover, problems caused by external environmental factors such as wind and rainfall were reported in the course of long-distance transportation. The results of this case comparison are expected to provide fundamental data that will reduce the amount of trial and error in the unit module production, transportation and lifting work in Korea, which has a comparatively small number of unit modular housing cases.

• 한국경영과학회지
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• 제33권4호
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• pp.53-61
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• 2008

Recently, Ertogral et al.[2] suggested two models considering the transportation cost based on single-vendor single-buyer integrated production-inventory problem. Although their problem-solving algorithm guarantees solutions obtained are optimal, a limitation is revealed that its performance can be inefficient due to complete enumeration search in a certain range. In this paper, a more efficient algorithm in finding optimal solutions is suggested for the same problem suggested by Ertogral et at.[2]. Numerical examples are presented for illustrative purpose.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2005년도 춘계학술발표회
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• pp.175-177
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• 2005

본 연구는 도서지방에 식수를 안정적으로 공급하기 위하여 도서별 특성에 적합한 최적의 상수원 방안을 마련하는데 목적이 있다. 특히 도서지역은 지형적인 특정상 상수원 확보를 위한 저수지 건설의 적지가 드물고 이상 가뭄과 환경오염으로 물 부족 현상이 심화되고 있으므로 도서지방의 안정적인 식수 공급 방안 수립은 시급한 실정이다.