• Journal of Advanced Marine Engineering and Technology
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• v.39 no.1
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• pp.68-74
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• 2015

This paper describes about the efficiency improvement of switched reluctance generator (SRG) over the rated speed region. Since the current shape has a great influence on the loss of the machine, so the system efficiency can be improved by optimizing the current shape. In case the wide speed range application such as wind power and medium size hydraulic power generation, a method of switching angle control is suggested to obtain the wanted current shapes. In order to verify the method, the experimental platform is set up. The feasibility of the theory is verified by simulation and experimental results.

• The Journal of Korean Institute for Practical Engineering Education
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• v.2 no.2
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• pp.113-119
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• 2010

The objective of this study is to perform the systematic research and to develop programs for improving the teaching abilities of vocational teachers, so that they can cope with the variant educational condition in accordance with the change of paradigm. Especially vocational teachers who engage in technical education can acquire new knowledge and techniques as well as grasp the trend of the new technologies required in industrial fields. In this study preliminary research for the capabilities of vocational teachers was held and the feasibility was investigated. Upon these investigations the essential elements for the improvement of vocational teachers' capabilities were derived. These will be used as preliminary data for operating curricula.

• International Journal of Automotive Technology
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• v.2 no.2
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• pp.63-75
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• 2001

This paper describes the development of THC reduction technologies compliant with SULEV regulations. Technologies embodied by the developmental work include improvement of fuel spray atomization, quick warm-up through coolant control shut of, and acceleration of fuel atomization for the fast rise of cylinder head temp inside the water jacket as well as the improvement of combustion state. The technologies likewise entail reduced HC while operating in lean A/F condition during engine warm-up with the cold lean burn technology, individual cylinder A/F control for improvement of catalytic converting efficiency, after-treatment such as thin-wall catalyst, HC-adsorber and EHC and etc, through vehicle application evaluation in cold start. We carried out an experimental as well as a practical study against SULEV regulations, and the feasibility of adopting these items in vehicle was likewise investigated.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.113-117
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• 2009

Fly ash (called FA hereafter) that results from thermal power plants is a long-term strength improving substance with reactivity to pozzolan and has been used for long. However, large amount of FA shows many advantages such as reduction of hydratio energy, long-term improvement in strength and economic feasibility and also has difficulties from reduction in initial strength and durability. In a preceding study, fine particle cement was applied to test the effects on initial strength. Therefore in this study, the effects of fine particle cement on the quality of FA concrete were reviewed. The results can be summarized as follows. Liquidity was increased by the most at FC substitution ratio of 15%. Air capacity was reduced according to increasing substitution ratio of FA and FC. Compressive strength showed high strength expression at all ages when FC was substituted at 45%. Synthesizing the above results, appropriate mixing of FC in FA concrete can improve liquidity, reduce unit quantity and show improvement in strength. In particular, mixed use of FC seems effective in improving early quality of concrete.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.1
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• pp.108-121
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• 2008

On January 1, 2005, the Korean Ministry of Environment put into operation a comprehensive program, so called 'Blue Sky 21' project, for the improvement of air quality in greater Seoul metropolitan area. This program was legally based on the 'Special Act on Metropolitan Air Quality Improvement' for Greater Seoul area, which was established in 2003, and should be updated every 10 years. The principal objective of this program is to improve the air quality in Seoul and surrounding area by 2014 to the levels of air quality in Tokyo and Paris, with particular emphases on reducing the concentrations of nitrogen dioxide and $PM_{10}$. Any regulation of the emission of toxic air pollutants in general, and $NO_2$ and $PM_{10}$ in particular, should be based on human exposure levels and consequential health effects. In this article, the contents and feasibility of the special program were critically evaluated with respect to the reduction of health risks. Important issues for improving not only air quality but public health are discussed, and future requirements for the success of the special program are suggested.

• Journal of the Korea Safety Management & Science
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• v.14 no.4
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• pp.271-279
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• 2012

Although digital contents markets grow very rapidly and are known as a higher value added industry, there is also potential risk in producing digital contents. Thus, many firms have begun to produce a firm's digital contents by outsourcing from other companies in order to catch-up new technologies and to make stable profits. However, since contracts are decided mostly based on bidding price and also standard contract are not available, there is a limit on the benefit from the contents outsourcing. Thus, this study argues that if both contract factors such as contract concreteness and flexibility are well managed, the on-line digital contents will increase the performance of a firm. This study deals with the influence on the firm's performance by the outsourcing in contract factors based on the empirical analysis. Using regression analysis with these two dependent variables, the findings showed that the contract concreteness had positive effects on both cost improvement performance and efficiency improvement performance, but the contract feasibility only had positive effect on efficiency improvement performance. In addition, the result of the study showed that the contract performance of outsourcing the digital contents have a positive impact on the partnership intention.

• Journal of the Korea Safety Management & Science
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• v.21 no.1
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• pp.9-16
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• 2019

Logistics companies are worrying about securing of differential competitiveness so as to be competitive companies in keen logistics market. The ground is how users are satisfied by sell-established service system to respond not only economic feasibility of logistics costs but also diversity and advancement of logistics needs. The competitiveness of logistics companies is also caused by customer satisfaction of service and only companies finding and satisfying customer needs continuously may be more competitive. For the competitiveness, it's the most important to analyze demands of current and potential customers and their pursuing value properly. Therefore, this researcher grasped PSL for online logistics service users with 5-point Likert-scale and quality-level decision method that consider the weighted value based on Kano model, measured customer's potential Demand for service through PCDI, and suggested methodology for deciding the priority of the improvement with loss function of Taguchi.

• Hwankyungkyoyuk
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• v.13 no.2
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• pp.74-90
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• 2000

The environmental quality in Korea was significantly deteriorated though the past economic development period. Even though the government has spent huge sum of resources on the policies and projects to improve the environmental quality, it is much removed from what the people hope for. To solve the environmental problems effectively, pollutants generated at source should be kept as minimum as possible, and possible, and pollutants from source be controlled before leaving the sources, and most of all, environmental strategies and systems be established and enforced properly. So, it is not too much to say that nation's environmental quality is entirely dependent on the education and training of the environmental managers such as environmental employees for air, water, and noise discharge facilities, technicians at environmental plants, and environmental officers of central and local governments. Regimes for the improvement of the education and training for environmental managers are suggested into four categories-educational institute, circular of the study, training contents and trainees. Referring to the improvement of integrated institute, and to improvement on educational institute, it is necessary to investigate the feasibility of integrated institute, and to recommend the inclusion of the local colleges and universities, and environmental societies. For the improvement on training courses, it is necessary that the non-obligatory course be expanded, and the courses be developed in such a way to meet the needs from the field. As for the improvement on training contents. It is suggested that the practical training on size be strengthened, and also full time environmental specialist and integrated committee be required to develop the effective circular and selection of proper lectures. Finally, environmental education for high ranked officers of autonomies, and international courses for developing countries are suggested.

• Journal of Environmental Impact Assessment
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• v.31 no.6
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• pp.438-448
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• 2022

This study is to improve the quantitative estimation index of biotop area ratio, which is an environmental planning index and environmental ecological planning technique, as a planning means that can induce the improvement of ecological soundness in the spatial planning stage. It is intended to identify the relative importance of space types and calculation indicators currently in operation, and to find alternatives through opinion analysis on improvement of space types and weights. As the method of this study, AHP analysis was performed to evaluate the relative importance of spatial types for in-depth analysis of spatial types and calculation indicators. In order to secure the reliability and objectivity of the study, 50 experts participated. Through this study, it can be linked with the improvement of technologies and construction methods, maintenance efficiency, economic feasibility, and construction technology, which are developed through analysis on the limitations and improvements by type of biotop area ratio. And it is expected to contribute to the improvement of the urban environment and vitalization of the biotop area ratio through the application of the biotop area ratio.

• New & Renewable Energy
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• v.5 no.3
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• pp.40-48
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• 2009

Recovered heat has been considered as a renewable energy in Europe since 2008 because its great effect on energy saving and carbon decreasing in plant process. Energy saving and decreasing green gas are critical issue today, so various technologies to save energy and decrease carbon dioxide in plant process have been applied to many industrial area. In this paper, the feasibility of condenser heat recovery by heat pump in power plant for district heating and fuel line preheating were reviewed by verifying energy (heat) balance and mass balance of power plant model. Some ways to compose proper system to recover heat of condenser are suggested and their possibilities are also reviewed. Limitations on heat recovery in power plant are also reviewed. The results are verified by calculating input/output energy based on actual performance test data of Taean Thermal Power Plant in Korea. There is noticeable improvement of plant performance in some cases which demand low temperature (<100 C) heat like distrcit heating, fuel line heating, and so forth.