• 전기학회논문지
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• 제58권6호
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• pp.1071-1077
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• 2009

Because several winds cause the a fault of transmission supply, KEPCO trys to protect the the trouble and supply the power stably. Kepco find out the weak mountains by winds and strengthen the power equipment annually. Power quality is the competition power in the international world and satisfy the customer using th power Therefore this paper deals with the fault relation between winds and transmission line.

• 산업경영시스템학회지
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• 제17권32호
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• pp.267-279
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• 1994

The Ministry of Transportation forecasts that the total number of automobiles in use in 1997 will be increased to about 10 million units. Until now, with the increase of domestic demand for automobiles, the customers' complaints have been raised frequently in relation with insufficient supply of auto parts for the repair and maintenance. At the same time, the industry came to face with new problems such as customers' requests of auto makers' quality services. Until now there were not any statistics on the registration of car age for each car type. So, for the auto makers' efficient aftersales management a system for collecting registration statistics was developed, and it has attributed remarkably to the improvement of the aftersales services, through easy anticipation of the requirements of parts being used for not only the small-produced but the massproduced car types. And a systematic instrument useful for auto industry, transportation and policy on environment is provided by timely supply of various statistics to the industry.

• Journal of Advanced Marine Engineering and Technology
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• 제18권2호
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• pp.75-82
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• 1994

The existence of peroodic impulse noises in distribution line carrier (DLC) communication system is known to be the most serious obstacle for improving DLC communication quality in reliability and capacity. From the spectral points, impulse noises can be divided into baseband type and modulation type the noise width of whichs are much different each other. With each nose type, this study presents the basic characteristics in relation to what they originate from and how their spectrum properties are revealed. The baseband type impulse noise is normally caused from thyristor circuit running with low switching speed and the modulation type noise from the circuit of switching power supply. The base wave of modulation noise is shown to be the pulsuatic charging current to primary condenser in switching power circuit. The study result indicates also that placing the DLC carrier frequency away the band predominated by modulated noise especially from RCC type switching power circuit is very important in DLC design.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1449-1451
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• 1997

Busbar made with Cu or Cu alloys and producted by Plastic manufacturing process. In this study, we research the manufacturing trend of Cu clad Al busbar for low cost and light weight which used for a electric power supply of distributing board. The objectives of this study is the manufacturing of composite busbar on electric power supply, the process and application for Cu clad Al busbar and the relation between electric properties and manufacturing operating process on contact parties.

• 한국안전학회지
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• 제14권1호
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• pp.3-9
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• 1999

The vortex tube is a simple device which splits a compressed gas stream into a cold stream and a hot stream without any chemical reactions. Recently, vortex tube is widely used to local cooler of industrial equipments and air supply system. In this study, the insulation effect of surface on the efficiency of vortex tube was performed experimentally. The experiment is carried out for nozzle area ratio of 0.194, diameter ratio of cold end orifice of 0.6 and input pressure ranging from 0.2Mpa to 0.5Mpa. The purpose of this study is focused on the effect of surface insulation of vortex tube with the variation of cold air mass flow ratio. The results indicate that the temperature difference of cold and hot air are higher about 12% and 30% than that of not insulated vortex tube respectively. Furthermore, for the insulated vortex tube, the similarity relation for the prediction of cold end temperature as the function of cold air mass flow ratio and input pressure is obtained.

• 대한전기학회논문지:전력기술부문A
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• 제51권8호
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• pp.403-408
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• 2002

As the electricity industry undergoes a process of fundamental restructuring, horizontal market power appears as a potential obstacle to a fully competitive wholesale electricity market. Market power is the ability profitably to maintain prices above competitive levels by restricting output below competitive levels. In models for imperfect competition under the consideration of the transmission constraints, the Nash equilibrium has the form of a mixed strategy. In this paper, the models for analyzing imperfect competition are compared using the solution of pure and mixed equilibria. The relation between market power and the capacity of a transmission line is investigated by imperfect competition analysis methods: Cournot, Bertrand, and Supply Curve model.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 춘계학술대회 논문집
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• pp.202-209
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• 2000

This paper introduces the main function and protection method of IGBT gate driver that designed by KOROS. Recently, the applications of insulated gate bipolar transistors(IGBTs) have expanded widely, particularly in the area of railway converters. This driver is suitable for railway traction applications, so they are designed for circumstance of railway vehicle such as vibration. The input control power for this driver is supplied from battery charger of railway. it is no necessary an isolated power supply board or auxiliary power supply, with substantial savings in cost and space in railway applications. This gate driver can be used wide range of input voltage. So, performance of the driver has no relation with the battery voltage(70V∼110V). The protection methods of IGBT gate driver have many kind of ways, but this gate driver it designed to apply to converter for railway system, so this gate driver includes protection for arm short current and low control power voltage, etc. And the process of protection method and protection reference value are optimized by means of sufficient test with our own facilities.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.660-664
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• 2005

There are operated the six thousand train in the interior of a country, $95\%$ of them are possible usage of resuscitation, Especially, Among them VVVF-Inverter vehicle has a merit of the highest recycle rate, but we don't use a apt recycled energy. Although the existing recycle energy used inverter method supply with electric power, it is decided in accordance with the state of sources. So efficiency of recycled electric power is of poor quality and catenary-voltage-fluctuation be generate because of recycled electric power. and it is able to affect system of safety train service. We'll research the method of supply according to wire condition after storing recycle energy made during train's stopping relation to Advanced EMU Research. Those methods are divided SMES, Fly-Wheel and Supercapacitor. and Considering the both economical efficiency and system application, we'll develop recycle energy storage system suitable our country condition.

• 한국조경학회지
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• 제21권4호
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• pp.43-53
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• 1994

This Study is to construct the Activity System Methods of Site Planning and Design. A planned spaces and facilities is considered usually in relation to users of space and facilities, user attributes, needs and values, and activity patterns. Information obtained form this study adds a qualitative dimension to the quantitative emphasis and supplies information for design-oriented analyses of site planning. In the design-oriented aspect, the concern is with devising desirable land use arrangements and facility supply considering objectives defined in the public interest. The design-oriented approache in site planning and design must use information on activity systems and space qualities in defining planning and design requirements of site development-one in the form of principles and standards of design used in land use and facility planning guidelines, and the other form of input variables for land use model and facility supply model.

• Asian-Australasian Journal of Animal Sciences
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• 제22권9호
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• pp.1334-1340
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• 2009

Sufficient food supply for all humans was, is, and will remain one of the main priorities for mankind. The choice between food from crops or animals is related to philosophical, religious and ethical, but also cultural and economical, values. However, the concept of sustainable agriculture takes into account the organization of food supply through future generations. Not only quantity, but also quality is important, especially in relation to food safety and the method of production. Specifically, the aspect of animal welfare is becoming increasingly important with the focus on stewardship and stockmanship, i.e. responsibility of humans for their animals. In the future, implications for sustainability in animal production may be of more concern to stewardship paired by stockmanship, responsibility, consciousness and morality. The moral as a basic concept of sustainable agriculture is to maintain continuous development in harmony with nature to meet requirements in the world for living creatures including human beings to live in and steward. The objective of this paper is to discuss the above issues from different viewpoints on sustainable food supply, increasing food consumption and environmental protection.