• KIEE International Transactions on Power Engineering
• /
• v.2A no.4
• /
• pp.166-173
• /
• 2002

Dispersed Generation (DG) units significantly effect the existing distribution protection practices. Therefore, new protection practices of the distribution system interconnected with DG units should be reevaluated and developed. In this paper, a new inter-tie protection scheme of DG units for distribution automatic reclosing is proposed. The impact of DG units on existing radial-sectionaliser coordination is analyzed. And the effects of the distribution reclosing type (radial and passive reclosing) on DG dynamics are analyzed and classified. From the results of the DG dynamic responses by the reclosing type, i.e. radial and passive reclosing, the inter-tie protection schemes of DG are introduced to improve the reliability and availability of utility interactive DG. The proposed schemes are proved and evaluated by a case study using PSCAD/EMTDC simulation.

• Proceedings of the KIEE Conference
• /
• 2001.04a
• /
• pp.163-166
• /
• 2001

It leaves much room for improvement that UTM-01 is of practical use. Therefor we will design of longitudinal pole magnet for UTM-02 system. The design of new magnet is based on light weight for bogie system. The new magnet for UTM-02 was reduced weight of magnet is 18kg per one, then it was ratio lift to weight is 10.13.

• Proceedings of the KIEE Conference
• /
• 1999.07e
• /
• pp.2256-2258
• /
• 1999

This paper describes preliminary discussions on spatial distribution of NO density, which is mostly contained in simulated NOx exhaust, between a wire-cylinder geometry discharge gaps by using Laser Induced Fluorescence(LIF) Spectroscopy, Spatial distribution of NO density will be measured with varying NO concentrations from 166 to 644 [ppm] and diameters of central electrode from 6 to 10mm. Pulsed Nd:YAG laser. Optical Parametric Oscillator(OPO), and Frequency Doubler are used to excite NO molecules to their excited state.

• Proceedings of the Earthquake Engineering Society of Korea Conference
• /
• 1997.10a
• /
• pp.159-166
• /
• 1997

The purpose of this thesis is to derive a theoretical model of the hysteretic resistance of the visco-elastic damper based on test results of harmonic excitation and to investigate of the basis of theory and experiment the effect of vibration control and response characteristics of portal frames degree vibration systems provided with the damper. The behaviour of a visco-elastic degree under dynamic loading is idealized by a model of the theory of visco-elasticity, i.e. a four-parameter model formed as a parallel combination of Maxwell fluid and Kelvin-Voigh models and its constitutive equation is derived. The model parameters are determined for a tested damper from the datas of harmonic excitation tests. The theoretical model of the damper is incorporated in equation fo motion of single degree of freedom. A computer program for solving the equation is written using Runge-kuttas's numerical integration scheme. Using this analysis program test cases of the earthquake excitation are simulated and the results of the simulation are the results of the simulation are the results of the simulation are compared with the test results.

• Journal of the Korea Safety Management & Science
• /
• v.14 no.3
• /
• pp.159-166
• /
• 2012

A*algorithm is highly useful to search the shortest route to the destination in the evacuation simulation. For this reason, A*algorithm is used to evaluate the evacuation experiment by the computer simulation. However there are some problems to analyze the outcome in relation to the reality. Because all the people in the building are not well-informed of the shortest route to the exit. And they will not move to the disaster spot though it is shortest route to the exit. Therefore, evacuation simulation program based on A*algorithm raise a problem of bottleneck phenomenon and dangerous result by damage surrounding the disaster spot. The purpose of this research is to prove the necessity for dispersion evacuation simulation by Multi agent system to solve the problems of the existing evacuation simulation program based on A*algorithm.

• Proceedings of the Safety Management and Science Conference
• /
• 2010.04a
• /
• pp.161-166
• /
• 2010

항공물류 분야의 개선을 위해 공항에서 연구와 투자를 통하여 공항 선진화를 이루고 있고, 우리나라도 지속적으로 증가하는 항공물류 분야의 개선이 필요하다고 인식하고 개선을 위한 방안을 연구하고 있지만, 항공물류 전반에 걸쳐 통합적인 개선이 이루어지지 않고 개별적이거나 부분적인 시스템 개선으로 중복 투자와 비효율성의 문제가 발생하고 있다. 본 논문에서는 이러한 문제점들을 해결하기 위해 현행 항공물류 프로세스를 수 출입으로 구분하여 분석하였고, 시스템 통합 사례들을 검토하여 프로세스 상에서 발생하는 문서들을 분석하였다. 이중 인터페이스 대상 문서를 선정하고 문서의 데이터 내용과 형식을 정의하였다. 정의한 데이터의 형식을 대상 문서에 코드로 적용시키고 시뮬레이션을 통하여 데이터 저장량을 비교 분석하였다. 이를 통해 항공물류 이해관계자간의 정보 교환이 용이해지고 동일한 정보를 재생성하거나 재가공하는 비효율성을 감소시킬 것으로 기대된다.

• Speech Sciences
• /
• v.12 no.4
• /
• pp.153-166
• /
• 2005

This paper attempts to examine the accent implementation and perception of noun phrases and compound nouns in English sentences, arguing that primary stress of noun phrase and compound noun is realized in relative prominence in intonation. The production test examines how the stress patterns of the noun phrases and compound nouns are realized in intonation of the English native speakers' utterances. The perception test investigates English and Korean listeners' comprehension of the intonation of the noun phrases and compound nouns. And the results of this experimental study show that speakers and listeners produce and perceive the primary stress as a relatively prominent accent even if in contrast of English listeners, Korean learners have difficulty in using the cue of pitch accent location and figuring out compound nouns and noun phrases.

• Proceedings of the IEEK Conference
• /
• 2000.07a
• /
• pp.163-166
• /
• 2000

The design, numerical simulation, and an experimental implementation of two-element cross-shaped microstrip line-fed printed slot array antenna for IMT-2000 at the 2.0 GHz band is presented in this paper. The proposed antenna with relative permittivity 4.3 and thickness 1.0mm is analyzed by the Finite-Difference Time-Domain (FDTD) method. It was shown that the measured 2.0 VSWR bandwidth of one-element microstrip slot antenna is from 1.42 GHz to 2.69 GHz, which is approximately 61.8% and that of two-element microstrip slot array antenna is from 1.42 GHz to 2.56 GHz, which is approximately 57.3% And it was shown that the measured gain of one-element microstrip slot antenna is 2.75 dBi and that of two-element microstrip slot antenna is 4.75 dEi. The antennas were fabricated and tested. The measured results are in good agreements with the FDTD results.

• Journal of the Korean Society of Safety
• /
• v.27 no.3
• /
• pp.161-166
• /
• 2012

This study deals with the accident of roundabout. The objective is to analyze the traffic accidents occurred in 3-legged and 4-legged roundabouts through the developed models. In developing the multiple linear regression models, this study uses the number of traffic accidents as a dependent variable and such the variables as geometric structures, traffic characters and others as the independent variables. The correlation and multicollinearity of variables were analyzed using SPSS17.0. The main results are as follows. First, R-square value of developed models were analyzed to be 0.851(3-leg) and 0.689(4-leg), respectively. Second, the independent variables in the 3-legged roundabout accident model were analyzed to be the traffic volume and number of crosswalk, and the variables in the 4-legged roundabouts were evaluated to be the traffic volume and signal. Finally, the paired t-test shows that the predicted values and observed values are not statistically different.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2014.10a
• /
• pp.164-166
• /
• 2014

주5일제 시행과 여가 활동으로서 여행에 대한 관심이 높아짐에 따라서 연안여객의 활용도는 높아질 것으로 예상된다. 하지만, 국내 연안여객 이용의 실태는 항로 부족, 항구의 노후화 등 개선해야할 과제가 많이 있다. 이러한 상황에서 연안여객의 대중교통화의 필요성이 제기되었다. 본 논문은 현재 연안여객의 항로 네트워크를 분석하여 대중교통화로 나아갈 수 있는 현재의 실태를 확인했다. 사용된 네트워크 분석지수는 지역중심성(degree centrality), 연결중심성(betweenness centrality)이다. 두 가지 지수에 따라 대중교통화에 기여하고 있는 항구의 순위를 확인했다. 분석결과가 연안여객의 대중교통화에 조금이나마 기여할 수 있기를 기대한다.