• International Journal of Automotive Technology
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• 제7권4호
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• pp.459-468
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• 2006

The objective of this paper is the development of the forward-looking dynamic simulation model of a hybrid electric vehicle(HEV) for a fuel economy study. The specification of the vehicle is determined based on two factors, engine peak power to curb weight ratio and specific engine power. The steady state efficiency models of the powertrain components are explained in detail. These include a spark ignition direct injection(SIDI) engine, an integrated starter alternator(ISA), and an infinitely variable transmission(IVT). The paper describes the integration of these models into a forward facing dynamic simulation diagram using the AMESim environment. Appropriate vehicle and driver models have been added and described. The controller was designed in Simulink and was combined with the physical powertrain model by the co-simulation interface. Finally, the simulation results of the HEV are compared with those of a baseline vehicle in order to demonstrate the fuel economy potential. Results for the vehicle speed error and the fuel economy over standard driving cycles are illustrated.

• 산업경영시스템학회지
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• 제24권66호
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• pp.37-45
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• 2001

Because the structure of the economy is being changed from product-oriented and company-centered economy to service-oriented and customer-centered economy, and the market competition is varying with the competition of non-price factors, the importance for customer service of logistics system is being increased. Thus, the level of customer service should be represented as an element of the logistics decision and the facility location decision. The level of customer service provided by logistics system has an effect on customers\` purchase decisions, hence on the market demand. That is, the market demand is elastic for customer service as it is influenced by product price. Considering the effect of customer service on demand, this study develops the market area which each facility will serve. That area is circular, and distance norm is considered Euclidean and Rectilinear (or Manhattan) distance norm. The market demand for product at a particular area is affected by the level of customer service that facility provides, and the relationship between the market demand and the level of customer service is represented with a mathematical function.

• 한국수소및신에너지학회논문집
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• 제34권2호
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• pp.122-131
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• 2023

Currently, major foreign countries such as Europe, the United States, Japan, and China have established policy and technology goals by 2050 to achieve the hydrogen economy. In line with this, Korea is also preparing to leap forward as a leading country in the world's best hydrogen economy by establishing a technology development target by 2050. In this paper, by examining and analyzing domestic and foreign policy and technology trends to date, implications for domestic hydrogen policy and technology trends are discussed, and major issues and future contents are summarized.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.737-743
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• 2005

Since the designation of the South Korean Construction industry as an open market industry by the World Trade Organization (WTO) in 1994, South Korea's construction firms were exposed to competition from firms of other advanced countries. Increased competition in the industry raised quality of production and lowered the cost of construction projects. Therefore, many big construction projects were planned and constructed with foreign construction partners during the last decade. Also, from those projects the South Korea Construction industry accumulated experience in and knowledge of both project management and construction management perspectives. However, in the process of conducting those big projects, many problems - specifically responsibility and the limit of competence - occurred between foreign construction partners. Hence, this study attempts to improve its role model that is for local and foreign companies to enter into Joint Ventures in the South Korea construction industry.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.614-615
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• 2015

In these days, global construction market is speedily increasing and domestic construction companies have a chance of new contracts. In the meantime, international projects have been increasingly forced to cope with potential risks, which seriously impacted achieving the targeted time and cost. In this study, we introduce a computerized risk management system for international EPCS projects, which is constructed on the needs of practitioners and decision makers as an aid to proactively control the potential risks and to monitor continuously their status and variation. The system is called the Project Risk Management System (PRiMS) is useful for furnishing project managers with warning signals as a project is progressing and helpful for producing the total risk score and tracking risk variation.

• 한국자동차공학회논문집
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• 제22권1호
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• pp.174-182
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• 2014

Recently, not only common types of hybrid electric vehicle (HEV) such as series or parallel but many other types of HEVs including 4WD hybrid electric vehicle have been developed and released. In this study, analysis of fuel economy and driving performance for 2WD and 4WD HEV are conducted using backward simulation based on dynamic programming. To analyze the characteristics of 4WD HEV, tire slip model based on vehicle dynamics was applied to the backward simulation program. As a result, 2WD HEV shows better fuel economy than 4WD HEV because of relatively simple configuration. However, in a severe road condition, 4WD HEV shows better driving performance that 2WD HEV had about 6% of impossible time to follow the driving cycle though the 4WD HEV had no impossible time.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 춘계학술대회
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• pp.250-252
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• 2015

창조경제를 내세운 박근혜 정부는 인력채용에 있어서도 학벌, 스펙 위주의 인재선발을 지양한다. 따라서 공공기관이나 기업이 창조경제를 뒷받침할 만한 인재선발을 추진하고 있다. 이를 위해 도입한 방식이 국가직무능력표준 이다. 특히 IT분야는 전 공공기관에서 인재가 필요하다. 따라서 본 논문은 국가직무능력표준의 IT인재 부문을 연구하고, 국가직무능력표준을 적용한 IT인재 선발에 대해 분석한다. 본 논문은 국가 공공기관 뿐만 아니라 창조 경제를 발휘하는 기업에서 필요한 IT인재상에 대한 중요한 연구 자료가 될 것이다.

• 한국수소및신에너지학회논문집
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• 제18권2호
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• pp.207-215
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• 2007

The rapid changes of energy environment such as high oil price, united nations framework convention on climate change, and the hydrogen economy have been happening to provide national energy security in the 21st century, we need to build strategic approach for coping with energy environment. From a long-term viewpoint of energy technology development, it's time to develop energy technology with selection and specification. In this study, we build energy technology roadmap for establishing the hydrogen economy with a long-term strategy. We analyze economic spin-offs and commercial potential for establishing energy technology roadmap of energy technology development for establishing the hydrogen economy.

• International Journal of Automotive Technology
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• 제8권5호
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• pp.651-658
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• 2007

This paper presents a new type of fuzzy logic-based power control strategy for fuel cell hybrid electric vehicles designed to improve their fuel economy while maintaining the battery's state of charge. Since fuel cell systems have inherent limitations, such as a slow response time and low fuel efficiency, especially in the low power region, a battery system is typically used to assist them. To maximize the advantages of this hybrid type of configuration, a power distribution control strategy is required for the two power sources: the fuel cell system and the battery system. The required fuel cell power is procured using fuzzy rules based on the vehicle driving status and the battery status. In order to show the validity and effectiveness of the proposed power control strategy, simulations are performed using a mid-size vehicle for three types of standard drive cycle. First, the fuzzy logic-based power control strategy is shown to improves the fuel economy compared with the static power control strategy. Second, the robustness of the proposed power control strategy is verified against several variations in system parameters.

• 동력기계공학회지
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• 제18권6호
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• pp.70-76
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• 2014

Surely fuel economy(F.E.) label is needed to meet consumer's right to know. Korea has developed and adopted F.E. correction equation similar to the feeling, because consumer complain about F.E. label higher than they feel. Recently, through continuous research and development high-efficiency & performance green car like HEV, PHEV and EV are being sold. In this situation, it is needed to know whether the current equation can reflect a part of their improved technic or not. In this paper, to review current equation through test using hybrid vehicles on 5-cycle SOC, correction equation and F.E were discussed. The result show HEV didn't meet the SOC error standard on US06. Also, HEV has bigger F.E. difference between FTP-75 and 5-cycle than conventional vehicles. However, the correction equation that include HEV almost same with current one.