• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.601-605
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• 2009

The paper deals with the proper design of GGH(gas-gas heater) panel elements of desulfurization equipments in a thermoelectric power plant. When fossil fuels such as coal, petroleum et cetera are burnt to ashes, sulfur oxide compounds are produced, and calcareous sludges are deposited at GGH panel elements. In this case, operation of a power plant equipments is interrupted, and a tremendous economic loss comes into existence. One of the purposes of the paper is to find flow velocity distributions and regions of depositions when calcareous sludges pile up on the GGH panel elements through the fluid analysis. In the fluid analysis, flow velocity and position distributions of particles between GGH panel elements are demonstrated according to time variation for ammonia and calcium hydroxide particles.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2009년도 정보통신설비 학술대회
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• pp.15-18
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• 2009

In recent years electric devices and telecommunication facilities were often damaged by surge generated lightning discharge. When the service was interrupted by failure of electrical devices due to surge the social loss is very enormous. Therefore in order to protect electrical systems against lightning, SPDs(Surge protective device) have been used But damaged SPDs often make some troubles like fire and interrupt of service. In this work, 3rd harmonic leakage current defection method was applied as the diagnosis of SPD degradation and the effectiveness of this method was verified by field survey.

• Journal of Information Display
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• 제12권4호
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• pp.195-198
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• 2011

Proposed herein is a flexible bistable chiral splay nematic display mode with an enhanced memory retention time under external distortion. By adopting the polymerized reactive-mesogen structure mixed in a liquid crystal layer, local anchoring energy is generated on the boundary between the polymer structures, and the relaxation from the ${\pi}$-twisted state to the initial splay state could be interrupted. As a result, the memory retention time becomes significantly longer, and the stability against the external distortion is enhanced.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.606-610
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• 1991

A relay is the one of small electrical components for automobiles and used for industry widely. We have developed the automation system for relay assembly and test to make it improve the productivity and decrease the man power. In order to determine the objective process of automation, we investigated 6 small and medium sized-enterprises and 1 greate sized-enterprise producing relays. And, we selected 2 model enterprises of them. One of the two is the system to develop. The scope of our study is the analyse of the conventional workcell, the determination of the system specification, the design of the system layout, the determination of the system cycle time, the design of the system mechanism, and the development of the controller for the system. We think that the developed system may be solve the technical and the economical problems interrupted efficiential automation of domastic small and medium sized-enterprises, and improve the international competitive power.

• 교육녹색환경연구
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• 제10권2호
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• pp.20-29
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• 2011

The purpose of this study is to suggest a scheme to provide children safer and more comfortable walking circumstances by survey current walking circumstances of schoolzone ways. A scheme suggested in this study was based on the analysis of survey to elementary school in 3 Newtowns(Dongtan, Dongbaek and Gumdan Districts) and actually surveyed data on school zone, the scheme can be summed up as follows; First, to avoid pedestrian roads being interrupted and to expend waiting space near schoolzone ways, several measures are needed including fixing roads and building additional gateway. Second, to secure pedestrians' safety in school zone ways should be planned and established more security concepts und facilities Third, to improve the walking safety in schoolzone way should be established specially "schoolzone B-plan".

• 교육녹색환경연구
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• 제8권2호
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• pp.12-21
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• 2009

The purpose of this study is to suggest a scheme to provide children safer and more comfortable walking circumstances by survey current walking circumstances of school zone ways. First, to avoid pedestrian roads being interrupted and to expand waiting space near school zone ways, several measures are needed including fixing roads, using schools' unemployed spaces and building additional gateway. Second, pedestrian crossings in front of school gate should be located at least 23.16m away from the left side of the gate. Third, on narrow path which cross main streets, the interval of pedestrian signal should be extended as against of the moment. And traffic calming facilities should be built on accurate position. Fourth, to secure pedestrians' safety and field of view, trees lining streets and any obstacles located within 10m from bus stop sign should be removed. Finally, education system about school zone ways should be improved to help children get used to more complicated roads' conditions.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.678-683
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• 2003

Ultrasonic method using SH(shear horizontal) wave has been developed to determine the surface damage in fatigued material. Fatigue damages based on propagation energy were analyzed by multiregression analysis and phase measurement in interrupted fatigue test specimen including CrMoV and 12Cr alloy steel. From the test results, as the fatigue damage increased the propagation time of the launched waves increased and amplitude of wavelet decreased. Also, analysis for the waveform modulation showed a reliable estimation, with confidence limit of 97% for 12Cr steel and 95% for CrMoV steel, respectively. Therefore, It is thought that SH ultrasonic wave technique can be applied to determine fatigue damage of in-service component nondestructively.

• Journal of applied mathematics & informatics
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• 제30권1_2호
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• pp.135-145
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• 2012

Traditionally, ERM (Equivalent Random Method) is used to determine number of circuits in an overflow circuit group with rough traffic which has vmr(variance to mean ratio) greater than one. Recently, IPP(Interrupted Poisson Process) approximate method which represents the collective feature of the overflow has been introduced. The negative binomial loss formula can be applied to determine the required number of circuits in the overflow circuit group. In this paper, we deal with the negative binomial loss formula and determination method of number of circuits. We also analyze and compare these three loss formulas.

• 한국정밀공학회지
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• 제24권2호
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• pp.73-85
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• 2007

The rear lateral collision warning system using fuzzy control algorithms is discussed in this paper. Common rear lateral warning system has many problems. For example if target vehicle comes into the warning area, it must unconditionally warn. Drivers could be interrupted by it. To solve the problem, I divided measuring area into two sections. One section is blind area of vehicle and the other rear lateral area. For blind area, obtained data was filtered inefficient warning signal by using relative velocity method. For rear lateral area, a fuzzy logic algorithm is used to recognition of obstacles. According to our experiment relative velocity method and fuzzy logic algorithms were very efficient.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.620-625
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• 2007

According to 'Metropolitan Traffic Network Plan' announced in 2001, radial railways which connect Seoul with satellite cities around Seoul appear gradually. And followed by this, social demand for circular metropolitan railways that can connect the radial railways horizontally is increasing. But existing plans about circular metropolitan railways has limits to propose only passing cities of the railways. If there is no detailed guideline for circular metropolitan railways, the each railway for circular line will be constructed individually and then it will be not effective circular railways totally. Additionally that railway project will be easily interrupted by popular complaints. Therefore "The basic plan for circular metropolitan railways" is needful to guide a right direction for circular metropolitan railways. In this paper, rough track diagram of 'node' station for circular metropolitan railways is proposed. It is essential part of the basic plan. If the track diagram of a node is publicized in advance and individually lines of circular metropolitan railways is enforced to followed it, all lines will has rich circular functionality. Finally, effective circular metropolitan railways can be built.