• Proceedings of the KIEE Conference
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• 1997.07a
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• pp.264-266
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• 1997

Fuel cell systems offer high energy efficiencies for transportation application. In addition, they can use alcohols and alternative fuels as the fuel, while producing little or no noxious emissions. Fuel cell-powered vehicles should be competitive in performance characteristics and in capital and maintenance costs with internal combustion engine vehicles. The objective of the present study is to design a fuel cell-powered passenger car to analyze technical feasibility.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.92-96
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• 2009

In this paper, economic analysis of Energy Storage System for power system is performed. Economic analysis is performed to show the benefits of Energy Storage System. Results illustrate the advantages of Energy Storage System not only acting as an alternative generation resource but also giving a better reliability and stability in power system.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.3
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• pp.410-416
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• 2010

Methane emitted from ruminant livestock is regarded as a loss of feed energy and also a contributor to global warming. Methane is synthesized in the rumen as one of the hydrogen sink products that are unavoidable for efficient succession of anaerobic microbial fermentation. Various attempts have been made to reduce methane emission, mainly through rumen microbial manipulation, by the use of agents including chemicals, antibiotics and natural products such as oils, fatty acids and plant extracts. A newer approach is the development of vaccines against methanogenic bacteria. While ionophore antibiotics have been widely used due to their efficacy and affordable prices, the use of alternative natural materials is becoming more attractive due to health concerns regarding antibiotics. An important feature of a natural material that constitutes a possible alternative methane inhibitor is that the material does not reduce feed intake or digestibility but does enhance propionate that is the major hydrogen sink alternative to methane. Some implications of these approaches, as well as an introduction to antibiotic-alternative natural materials and novel approaches, are provided.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.2
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• pp.15-22
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• 2002

Lately, our world is faced with very serious problems related to the increased air pollution of the exhaust emissions from automobiles. In particular, the exhaust emissions of diesel engines are recognized as a main cause which strongly influence environment. Lots of researchers have attempted to develop various alternative fuels to reduce these harmful emissions in diesel engine. The purpose of this investigation is to evaluate the possibility of esterfied rice bran oil for diesel fuel substitution in a naturally aspirated D. 1. diesel engine, and also find means to reduce smoke emissions in esterfied rice bran oil combustion. The smoke emission of esterfied rice bran oil is reduced remarkably in comparison with commercial gas oil, that is, it was reduced approximately 58.2% at 2500rpm. But, power, torque and brake specific energy consumption didn't have no large differences. It was concluded that esterfied rice bran oil can utilize effectively as an alternative and renew- able fuel fur diesel engine.

• Steel and Composite Structures
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• v.20 no.5
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• pp.1133-1153
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• 2016

In this article, an additive performance ratio method using structural analysis of both 2D and 3D is introduced to mitigate the complexity of work evaluating structural performances of numerous steel outrigger alternatives in multi-story buildings, especially high-rise buildings. The combined structural analysis process enables to be the design of economic, safe, and as constructional demanding structures by exploiting the advantages of steel, namely: excellent energy dissipation and ductility. First the approach decides the alternative of numerous steel outriggers by a simple 2D analysis module and then the alternative is evaluated by 3D analysis module. Initial structural analyses of outrigger types are carried out through MIDAS Gen 2D modeling, approximately, and then the results appeal structural performance and lead to decide some alternative of outrigger types. ETABS 3D modeling is used with respect to realization and evaluation of exact structural behaviors. The approach reduces computational burden in compared to existing concepts such as full 3D analysis methods. The combined 2D and 3D tools are verified by cycle and displacement tests including comprehensive nonlinear dynamic simulations. The advantages and limitations of the Additive Performance Ratio Approach are highlighted in a case study on a high rise steel-composite building, which targets at designing the optimized alternative to the existing original outrigger for lateral load resisting system.

• Journal of Distribution Science
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• v.19 no.1
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• pp.5-15
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• 2021

Purpose: This study explores the types of relational benefits that generate loyalty to room-sharing services among Chinese customers based on the relationship marketing literature. The study also examines the moderating effect of alternative attractiveness on this relationship. Research design, data and methodology: Based on research hypotheses, questionnaires with items measuring the proposed constructs in three dimensions, including relational benefits, alternative attractiveness, and customer loyalty, were designed to test the hypotheses. Data were collected via an online questionnaire of 220 room-sharing service customers in China. Results: Results verify the effects of relational benefits on customers' loyalty to room-sharing services and the mediating effect of alternative attractiveness. More specifically, confidence, social, and safety benefits positively affect customer loyalty to room-sharing services, and alternative attractiveness moderates only the effect of social benefits. Conclusions: The results suggest that room-sharing service providers should concentrate on providing confidence, social, and safety benefits to maintain long-term relationships with customers. This study also provides practical implication for building relationships between channel members in service distribution channels. The study concludes that without customer relationships marketing for managing collaborative and social communication channels, the entire distribution channel might lose out eventually.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.732-734
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• 2015

Because of the increase in information and knowledge sharing in various fields, technological development across various industries were growing energy demand. Advanced technologies was done to find alternative energy sources. Relevant studies are under way to promote efficiency of energy source. The problem of climate change is not the only reason why made electric cars. it is because of the efficiency of the utilization of alternative energy sources has improved. In this paper we focuses about usage of thermoelectric effect with electric cars.

• Proceedings of the KIEE Conference
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• 2005.04a
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• pp.277-279
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• 2005

The imbalance of energy demand and supply caused by rapid industrialization around the world and the associated environmental issues require and alternative energy source with possible renewable fuels. Political instability and depletion of cruel oils are other factors that cause fluctuation of oil price. Securing a new alternative energy source for the next century became an urgent issue that our nation is confronting with. As a matter of fact, the fuel cell technology can be widely used as next generation energy regardless of regions and climate. Specially, the ability of expansion and quick installation enable one to apply it for distributed power, where the technology is already gaining remarkable attentions for the application. Particularly, leading industrialized nations are focusing on the PEM fuel dell with anticipation that this technology will find their place of applications in the vehicles and homes. In this study, demonstrate the multi physics modeling of a proton exchange membrane(PEM) fuel cell with interdigitated flow field design. The model uses current balances, mass balance(Maxwell-Stefan diffusion for reactant, water and nitrogen gas) and momentum balance(gas flow) to simulate the PEM fuel cell behavior.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1999.11a
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• pp.119-124
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• 1999

A selection methodology of liquid levelmeters, especially, level sensors in non-nuclear category, to be installed in nuclear energy facilities is developed using linguistic fuzzy approaches such as fully-linguistic and semi-linguistic methods. Depending on defuzzification techniques, the linguistic fuzzy methodology leads to either linguistic (exactly, fully-linguistic) or cardinal (i.e., semi-linguistic) evaluation. For the linguistic method, for each alternative, fuzzy preference index is converted to linguistic utility value by means of a similarity measure determining the degree of similarity between fuzzy index and linguistic ratings. For the cardinal method, the index is translated to cardinal overall utility value. According to these values, alternatives of interest are linguistically or numerically evaluated and a suitable alternative can be selected. Under given selection criteria, the suitable selections out of some liquid levelmeters for nuclear facilities are dealt with using the linguistic fuzzy methodology proposed. Then, linguistic fuzzy evaluation results are compared with qualitative result available in the literature. It is found that as to a suitable option the linguistic fuzzy selection is in agreement with the qualitative selection. Additionally, the comparative study shows that the fully-linguistic method using adequate scale system facilitates linguistic interpretation regarding evaluation results.

• Journal of Korean Society for Atmospheric Environment
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• v.4 no.1
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• pp.45-57
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• 1988

This is a close relationship between energy consumption and the way in which we develop and manage our regions. This study has estimated and compared energy requirements for the journey to work, resulting from alternative population and employment growth patterns in a rural-urban regional settlement of Korea. The broad scope of work was as follows: i) Select the study area ii) Formulate alternative growth patterns iii) Develop the Hansen and double-constrained gravity model iv) Application of Vogel's approximation method and the developed Hansen and gravity model to the case study area. v) Analyze the relationship between spatial structure, transport energy-requirements and environmental pollution. At issue here is the trade-off between air pollution averages and variations. Policies concentrating manufacturing industry and other regional facilities, for instance, may indeed reduce average pollution levels at the benefit of less-car miles, thus, reducing auto pollution, in the region, but increase local pollution peaks.