• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전력기술부문
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• pp.99-101
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• 2006

As the same concept with GIB, GIL(Gas Insulated Line) has been established and run for the first time in New Jersey, America, in 1972. At the beginning, the installation condition of GIL was complicated and the construction cost was excessive, so it was not economical, but the construction cost was substantially reduced with the use of insulation material which is the mixture of $SF_6$ and $N_2$ Gas in Germany, in 1990s. And also comparing to cable, GIL has lots of advantages, such as being capable of the high voltage transmission, being applied to reclosing and lowering the strength of electromagnetic force, Due to these advantages, GIL is recently accepted in many countries.

• Communications for Statistical Applications and Methods
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• 제8권3호
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• pp.685-696
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• 2001

Robust design is an approach to reducing performance variation of response values in products and processes. In the Taguchl parameter design, the product-array approach using orthogonal arrays is mainly used. However, it often requires an excessive number of experiments. An alternative approach, which is called the combined-array approach, was suggested by Welch et. al. (1990) and studied by others. In these studies, only single response variable was considered. We propose how to simultaneously optimize multiple responses when there are correlations among responses, and when we use the combined-array approach to assign control and noise factors. An example is illustrated to show the difference between the Taguchi's product-array approach and the combined-array approach.

• Geomechanics and Engineering
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• 제6권1호
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• pp.33-45
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• 2014

Use of geotextile as reinforcement material to improve the weak soil is a popular method these days. Tensile strength of geotextile and the soil-geotextile interaction are the major factors which influence the improvement of the soil. Change in fine content within the sand can change the interface behavior between soil and geotextile. In the present paper, the bearing capacity of unreinforced and geotextile-reinforced sand with different percentages of fines has been studied. A series of model tests have been carried out and the load settlement curves are obtained. The ultimate load carrying capacity of unreinforced and reinforced sand with different percentages of fines is compared. The interface behavior of sand and geotextile with various percentages of fines is also studied. It is observed that sand having around 5% of fine is suitable or permissible for bearing capacity improvement due to the application of geosynthetic reinforcement. The effectiveness of the reinforcement in load carrying capacity improvement decreases due to the addition of excessive amount of fines.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2007년 가을학술발표회
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• pp.160-169
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• 2007

In this study, Analyzed stress history, state of stress, ratio of stress/strength to use FEM. Fault Zone depth is 3m, 6m, 9m, 12m and 15m for study, and also Distance is 3m, 6m, 9m, 12m and 15m at center of tunnel with thickness 3m fault zone. It is not appeared that Arching in stress state and stress history by FEM. On the other hand, excessive shear stress and high compressive stress happened. Therefore, Tunnel design is desirable that do it so that state of stress that is the imbalance may be uplemented. it is important that examine each state of stress and stress history in detail tunnel design.

• 한국데이터정보과학회:학술대회논문집
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• 한국데이터정보과학회 2003년도 춘계학술대회
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• pp.65-75
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• 2003

In the Taguchi parameter design, the product array approach using orthogonal arrays is mainly used. However, it often requires an excessive number of experiments. An alternative approach, which is called the combined array approach, was suggested by Welch et. al. (1990) and studied by others. In these studies, only single response variable was considered. We propose how to simultaneously optimize multiple responses when we use the combined array approach.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.234-240
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• 2000

The Energy is the basis for almost all industrial activities and domestic needs. But recently there are increasing concerns internationally over environmental problems and consequent climate changes caused by the excessive use of fossil fuels. Furthermore the price of crude oil is increasing steadily with unstable supplies. In order to solve these national energy problems, the utilization of Ocean Energy is introduced as one of the best alternative technologies for the future. OTEC Power Plant has been installed at the West Inchon Power Plant Site. Temperature differences of $20{\sim}25^{\circ}C$ have been utilized for plant operations, where R22 is used as a working fluid. The system is composed of low pressure turbine, plate type heat exchanger, and pumps. In the present investigation the experimental results, such as gross power, net power and objective function, are analysed when temperature differences change from the reference design point.

• 한국콘텐츠학회논문지
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• 제10권2호
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• pp.215-223
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• 2010

산업혁명 이후 인류의 화석연료 사용 증가에 따른 이산화탄소($CO_2$) 배출 확대로 온실가스가 지구 온난화의 주된 원인으로 밝혀지면서 선진국을 중심으로 세계 각국들은 온실가스 감축을 위해 경제 개발 도시 환경 정책 등 다양한 분야와 적극적으로 결합하여 신재생 에너지 - 태양광 기술을 이용한 디자인 요구가 급증되고 있다. 따라서 본 연구에서는 이러한 문제를 해결하기 위한 대안의 하나로 태양광 기술을 적용한 공중화장실을 제시하고자 한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.510-513
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• 2001

Several kinds of vibration problems have been frequently encountered in industrial vertical pumps in spite of their widespread use for long time. In fact, vibration problems of the vertical pumps are so complicated and difficult with compared to those of the horizontally mounted pumps that more careful attention should be taken for solving the vibration problems. This paper introduces a case study experienced from troubleshooting for excessive vibration occurred in a vertical-type condensate pump for combined cycle power plants. Subsynchronous whirl vibration was caused by the instability of the guide bearing whose lubricant is water. A newly modified guide bearing has solved the vibration problem, which should be the best countermeasure.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1420-1423
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• 1990

DC series motor has been widely applicated in industry due to many advantageous characteristics, such as high starting torque, easy construction of its controller, and cost economy, etc.. However, by high starting current, excessive surge voltage, and so on, many problems which could make engineers relinguish to use it are induced. In this paper, various protection methods for power circuit are discussed. Particularly, a new proposed snubber circuit which consists of two diodes, one capacitor, and a resistor increases the performance with respect to the suppression of the surge voltage. Furthermore, the plugging algorithm, by checking the armature current and voltage and controlling the field coil current, is designed and implemented. Also, these methods and algorithms were applicated in electric vehicle, and we could find its stability to be considerably improved.

• 한국시뮬레이션학회논문지
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• 제14권4호
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• pp.77-86
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• 2005

[ $IP^2$ ] (IP-based IMT Network Platform) is a ubiquitous platform supporting mobility using two step If address IPha (IP host address) and IPra (IP routing address) - in a backbone network. MN (Mobile Node) in $IP^2$ maintains either Active or Dormant state, which is transferred to Active state through Paging process when communication is required. In this paper, we proposed a Paging method using proxy to resolve the problem of the conventional Paging method which transmits the Paging messages to all cells in LA (Location Area) resulting in the excessive use of network resources. Performanceevaluation of the proposed method using NS-2 showed that the usage of network resources becomes more efficient by reducing paging loads, especially under the condition of increased nodes.