• Journal of Magnetics
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• 제21권1호
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• pp.72-77
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• 2016

Although the initial cost of permanent-magnet linear synchronous motors is high owing to the installation of armatures over the full length of the transportation lines, linear motors are useful for transportation systems because of their high speed, acceleration, and deceleration. For these reasons, research into reducing the cost of linear motors is necessary, and a stationary distributed-armature system has been suggested for installing armatures in sections where acceleration and deceleration of the mover are required. However, each armature has ends that significantly increase the cogging force, resulting in the increase in the thrust ripple of the mover. Therefore, in order to improve the thrust ripple of the system, the present study aims to provide auxiliary teeth on both ends of the armature to achieve an optimal design through an analysis of the contribution ratio with respect to factors regarding the design of the experiment and the objective function.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.219-225
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• 2013

State transportation agencies utilize fleets of heavy equipment to construct and maintain roadways. Equipment cost models can be developed to forecast economic life, which is the point at which the average unit cost to date reaches a minimum. A calculated economic life and cost models can be used to quantify the impacts of management strategies applied to a fleet. The purpose of this research was to develop an accurate method of quantifying the results of management strategies applied to a fleet of heavy construction equipment. The strategies evaluated are related to the annual usage of the fleet and the size of the fleet. More specifically the methodology is used to adjust the economic model to consider a limit to the annual decline in machine usage and a reduction in the number of machines in the fleet. When limiting annual machine usage, a specified rate is applied to the usage of the fleet, while total usage is held constant. This causes aging at a modified rate. A reduction in fleet size also causes a change to the usage of a fleet as the fleet must use fewer machines to produce the same total usage.

• 디지털융복합연구
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• 제17권2호
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• pp.135-144
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• 2019

대형마트보다 저렴하고 편의성도 높은 창고형 매장에 대한 물류 중요성이 증대되고 있다. 하지만 창고형 매장의 통합 Depot 위치선정에 관한 연구는 부족한 실정이다. 이러한 측면에서 본 연구에서는 통합 Depot 위치선정을 위한 요인도출 및 가중치 산출, 대상지의 위치 우선순위 산정을 다기준 의사결정 방법인 AHP(Analytic Hierarchy Process)방법을 도입하여 계산하는 것을 연구의 목적으로 한다. 분석결과, 선정 요인별 중요도에서는 수배송 비용절감(0.198)이 가장 높게 나왔으며, 수배송 거리절감(0.168), 수배송 시간절감(0.149) 순으로 도출 되었다. 본 연구 결과는 Depot를 통합 운영 시 비용 절감과 효율성 증가를 수치화하여 실제 실무자들에게 보다 현실적인 기초자료를 제시할 수 있을 것으로 판단된다. 향후연구에서는 분석에 사용되는 요인의 추가작업을 통하여 분석모형을 정교화 할 필요가 있다.

• 한국지형학회지
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• 제18권1호
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• pp.15-27
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• 2011

중국과 북유럽의 운하는 건설당시 시대상과 자연환경이 우리나라와 다음과 같은 점에서 매우 다르다. 우리나라 하천은 하상계수가 크고 중상류 하천들은 구배가 커서 주변지역으로부터 역과 토사가 하상에 유입·퇴적되어 유로를 변경하거나 수심을 낮게 한다. 이는 지속적인 준설작업을 필요로 하며 보와 갑문의 설치는 홍수 때 유수의 흐름을 지체시켜 범람의 원인이 되기도 한다. 그리고 지하수면의 상승 또는 하강으로 기존도시의 시설에 치명적일 수 있을 뿐만 아니라 수질 악화와 홍수시 수위상승을 유발하여 홍수 유발의 원인이 된다. 준설작업은 생태계 파괴를 초래하고 운하의 경제성 여부와 육상교통에 비하여 상대적으로 낮은 속도 문제, 운송비 절감과 이적(移積)비용과 종착지 비용 문제, 관광·레저 산업의 활성화와 과도한 개발비용 등의 문제가 있다. 운하가 아닌 단순한 관리와 정비 사업은 순차적으로 계획을 세워 추진하는 것이 보다 타당하다.

• 한국산업융합학회 논문집
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• 제14권1호
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• pp.29-36
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• 2011

This study analyzed the convenience and productivity before and after adopting self-propelled power transportation devices to the harvest and transportation of fruit and vegetable products in the Gyeongbuk region, by applying the REBA and RULA techniques. In the REBA analysis, the work risk was low with 4~6 points before adoption which became 2~3 points after adoption. As for the RULA analysis, work loading appeared to have decreased with 6~7 points before adoption which became 3~4 points after adoption. The annual work time reduction was about 48~179 hours while labor costs were reduced to 364~1,345 thousand won annually. This indicated a labor cost reduction effect of about 10~15%. Therefore, the adopted self-propelled power transportation devices appeared to prevent musculo skeletal diseases of the human body and also improve productivity even after using it for long hours according to the REBA, RULA measures level.

• 대한교통학회지
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• 제32권5호
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• pp.421-430
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• 2014

수송 분야의 온실가스 감축에서 차량운행 중 공회전에 따른 온실가스 발생 문제는 중요한 요소이므로 최근 버스, 트럭, 택시에서의 공회전제한장치(ISG) 장착이 법제화되고 있으며, 일반 승용차에도 ISG 장착을 확대하려는 추세이다. 이에 본 연구에서는 수도권 지역을 대상으로 승용차의 차종별 ISG 장착 전략에 따른 경제적 효과분석 결과를 기반으로 그에 따른 정책 방향성을 제시하고자 한다. 분석 결과, 서울시 사업용 승용차에 ISG를 장착하는 전략이 가장 효과적(B/C: 8.55)으로 나타났고, 그에 따른 연료절감량은 660(${\ell}$/년/대)이며, $CO_2$ 저감량은 1,606(kg/년/대)인 것으로 분석되었다. 이러한 결과는 향후 일반 승용차의 ISG 장착에 대한 적정 보조금 산정 등의 정책 판단 지표로 활용 가능할 것으로 판단된다.

• 디지털융복합연구
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• 제15권10호
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• pp.123-132
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• 2017

본 연구는 북중국과 한국을 대상으로 화주의 내륙운송 의사결정 요인과 영향을 확인하는 것을 목적으로 하였다. 선사와 화주 및 포워더가 항만을 선택할 때 미치는 결정요인들을 선행연구를 통해 도출한 후, 요인분석과 Fuzzy-AHP를 활용하여 실증분석을 하였다. 요인분석 결과 항만 물류비용 및 배후지역 접근성, 터미널 운영, 항만입지 및 시설, 항만 종합서비스, 피더 네트워크가 대요인으로 도출하였다. 집단 간 중요도에 대한 분석결과로서 항만물류 및 배후지역 접근성이 선사와 화주 및 포워더에게 가장 중요한 요인이라는 사실을 발견할 수 있었다. 피더 운송비용이 선사에게 가장 중요한 세부요인인 반면 내륙운송비가 화주와 포워더에게는 가장 중요한 요인이라는 사실을 확인할 수 있었다. 본 연구결과를 통하여, 화주의 최대 관심사중 하나가 내륙 운송비 절감이라는 사실을 확인할 수 있었다. 또한 항만선택의 결정권이 선사에서 화주 쪽으로 이전되는 주요요인은 내륙 운송비 절감이라는 것을 제시하였다.

• 전기학회논문지P
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• 제64권4호
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• pp.273-276
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• 2015

In this paper, ESS capacity installed in industrial customer is calculated using economic analysis. To do this, electric charge for industrial customer is analyzed and power management system(PMS) of ESS is selected. Reduction of kW cost and kWh cost are set to 'benefit' according to operation of ESS. Also, installation cost and maintenance cost of ESS are set to 'cost'. Proper ESS capacity is determined as a result of benefit-to-cost(B/C) analysis according to the variation of ESS installation cost. In case study, B/C is analyzed for the specific industrial customer and minimum capacity of ESS to make a profit are proposed for the customer.

• 한국도로학회논문집
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• 제18권6호
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• pp.1-10
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• 2016

OBJECTIVES : Currently, the market for carbon emissions trading has been increasing. In Korea, it is known that traffic mode rate in bike transportation is low. However, if bike transportation system is encouraged and the traffic mode rate is increased, it would be possible to reduce carbon emissions through the trading market. In this study, a practical policy to activate the bike transportation system in Korea will be proposed and verified. METHODS : Past studies regarding bike transportation system in international and domestic metropolitan cities were analyzed. Moreover, detailed reviews on recent carbon emissions trading market were performed. In particular, SWOT analysis on the bike transportation system in Korea and policy topology analysis were conducted. RESULTS : Based on the literature reviews and SWOT analysis, a new bike transportation policy was proposed. Several actual plans to adopt in Korea were proposed. In addition, a new bike transportation policy was analyzed using policy typology model, and a business model related to the cost of implementing the system and CERs were also proposed. CONCLUSIONS : It is concluded that the proposed bike transportation activation policy and several practical plans to connect CERs and a business model including bus, subway, T-money and bike riders to give some incentive were effective and reasonable. It is desired that this study will help Korea to get CERs through bike transportation activation in the future.

• 한국안전학회지
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• 제31권3호
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• pp.143-155
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• 2016

Recently, a massive loss of life and property is occurring in Korea due to traffic accidents, with the rapid increase in cars. For improvement of traffic safety, the Korea Transportation Safety Authority intensively analyzes accident data in local governments with low traffic safety index, performs a field investigation to extract problems and offers local governments improvements for problems, by conducting the 'Special Survey of Actual Conditions of Traffic Safety' each year, starting 2008. But local governments cannot strongly push forward the improvement projects due to the limited budget and the uncertainty of the improvement plan effects. Therefore, this study suggested a model which applied the Utility concept to the AHP theory, in order to efficiently decide a priority of the improvement plans in accident black spots in consideration of the limited budget of local governments. The number of accidents in each spot for improvement and accident severity, traffic volume, pedestrian volume, the improvement project cost and the accident reduction effect were chosen as evaluation factors for deciding a priority, and data about the improvement plan costs and the accident reduction effects, traffic accidents and traffic volume in the spots to undergo the special research on the real condition of traffic accident in the past were collected from the existing studies. Then, regression analysis was carried out and the Utility Curve of each evaluation factor was computed. Based on the AHP analysis findings, this study devised a priority decision method which calculated the weight and the utility function of each evaluation factor and compared the total utility values. The AHP analysis findings showed that among the evaluation factors, accident severity had the biggest importance and it was followed by the improvement plan cost, the number of accidents, the improvement effect, traffic volume and pedestrian volume. The calculated utility function shows a rise in utility, as the variables of the 5 evaluation factors; the number of accidents, accident severity, the improvement plan effect, traffic volume and pedestrian volume increase and a fall in utility, as the variables of the improvement plan cost increase, since the improvement plan cost is included in the budget spent by a local government.