• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.4
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• pp.26-35
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• 2003

For the recognizing system to be classified the same or different images in the nature the rotation, scale and transition invariant features is to be necessary. There are many investigations to get the feature for the recognition system and the log-polar transform which is to be get the invariant feature for the scale and rotation is used. In this paper, we suggested the character recognition methods which are used the centroid method and the log-polar transform with the interpolation to get invariant features for the character recognition system and obtained the results of the above 50% differential ratio for the character features. And we obtained the about 90% recognition ratio from the suggested character recognition system using the BPEJTC which is used the invariant feature from the Mellin transform method for the reference image. and can be recognized the scaled and rotated input character. Therefore, we suggested the image character recognition system using the Mellin transform method and the BPEJTC is possible to recognize with the invariant feature for rotation scale and transition.

• Journal of Korea Port Economic Association
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• v.27 no.1
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• pp.31-54
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• 2011

This paper classifies and defines the infrastructure factors required to performance various logistics activities in domestic logistics centers as base facility, logistics facility, logistics equipment and operation system. The classification of infrastructure factors in this research provide the standard to be able to identify which infrastructure influence on logistics activities directly or indirectly. Also, this paper reviews Korean industrial Standards('KS') related to logistics center and then suggests the reformation of KS reflected on the logistics activities and infrastructures with field-study(321 domestic centers) and advisory meeting1). This review and suggestion can increase the low awareness and use of KS. Lastly, this paper can contribute to increase the effective of logistics centers' plan and operation by providing the improvement direction of KS regarding to logistics centers.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.6
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• pp.154-159
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• 2003

In this paper, we proposed variable threshold dual rate ADPCM coding method which adapts two coding rates of the standard ADPCM of ITU G.726 for speech quality improvement at a comparably low coding rates. The ZCR(Zero Crossing Rate) is computed for speecd data and under the noisy environment, noise data dominant region showed higher ZCR and speech data dominant region showed lower ZCR. The speech data with the higher ZCR is encoded by low coding rate for reduced coded data and the speech data with the lower ZCR is encoded by high coding rate for speech quality improvements. For coded data, 2 bits are assigned for low coding rate of 16[Kbps] and 5 bits are is assigned for high coding rate of 40[Kbps]. Through the simulation, the proposed idea is evaluated and shown that the variable dual rate ADPCM coding technique shows the qood speech quality at low coding rate.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.1
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• pp.92-99
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• 2009

Deeply-driven ground rod in the rainy season may contact with rainwater and ground water. When surge voltages are applied to the submerged ground rods, the ionization around the ground rods are occurred. Ionization in soil and/or water is affected in dynamic performance of ground rod systems. This work aims at studying the transient performance of ground rod system under impulse voltage using scale model in an electrolytic tank. The potential reduction and energy dispersion caused by ionization were treasured and quantitatively analyzed using the Matlab Program. As a result, the peak voltage at the terminal of ground rod was varied with water resistivity and charging voltage of Marx generator. The potential at the terminal of the ground rod was approximately reduced to a half of the applied voltage just below breakdown voltage. Also the energy more than half of the applied energy was dispersed through the ground rod due to ionization just below breakdown voltage.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.8
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• pp.126-132
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• 2010

This paper presents dielectric characteristics of $N_2$ gas under impulse voltages in a quasi-uniform electric field gap. The experiments were carried out at the test gap applied by the 1.2/50[${\mu}s$] lightning impulse voltage, 180/2500[${\mu}s$] switching impulse voltage, 500[ns]/1[MHz] very fast transient overvoltage(VFTO). The gap separation of sphere-to-plane electrodes was 14[mm] and the electric field utilization factor was about 71.2[%]. The gas pressure ranges from 0.2 to 0.6[MPa]. As a result, the electrical breakdowns are occurred by streamer discharge. Breakdown voltages are linearly increased with the gas pressure and the highest breakdown voltage is appeared under the VFTOs having fast rising time. Breakdown voltages under the positive impulse voltages were higher than those under the negative ones, and also the time to breakdown in the positive polarity is longer than that in the negative polarity.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.8
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• pp.142-149
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• 2010

This paper describes dielectric characteristics of $SF_6$ and dry-air gases under lightning impulse voltages in a quasi-uniform electric field. In order to simulate to a quasi-uniform electric field, electric field utilization factor of the used sphere-plane electrode is 71[%]. The gas pressure of $SF_6$ ranges from 0.1 to 0.2[MPa] and that of dry-air ranges from 0.2 to 0.6[MPa]. Electrical breakdown voltages of $SF_6$ and dry-air gases are measured and analyzed as functions of the polarity of lightning impulse voltage and gas pressure. As a result, the electrical breakdown voltage of both gases under the positive lightning impulse voltage is higher than that under the negative one. The electrical breakdown voltage in $SF_6$ is almost higher than 2.67 times compared to dry-air. The results presented in this paper can be used as a useful information to evaluate the capability of alternative insulation gases for $SF_6$ in power distribution equipment with prominent ability against lightning surge.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.2
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• pp.143-150
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• 2010

Vitrification technology has been gradually recognized as one of effective solidification methods for concentrated boric acid wastes generated in PWR. Vitrification for low- and intermediate-level radioactive wastes has a large volume reduction and good durability for the final products. A feasibility study for the vitrification of concentrated boric acid wastes has been performed with developing the pre-treatment methods of powdered wastes, glass compositions using glass formulation and demonstration test. The pre-treatment method is pelletizing the powder type for stable feeding within cold crucible melter. The glass compositions should be developed considering molten glass are related with wastes reduction. High contents of sodium and boron within borate wastes give influence to waste loading. A variety of factors obtained from the demonstration test are reviewed, which is wastes feeding rate, off-gas characteristics on stack and glass characteristics of final products such as durability for implementing the wastes disposal requirement. The aim of this paper is to present the feasibility of vitrification and review the solidification method for concentrated boric acid wastes and obtain the physicochemical characteristics of solidified glass.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.23 no.12
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• pp.217-223
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• 2009

This paper shows a reasonable contract power conversion factor, that was made by the systematic and statistical way considering actual conditions, such as investigated contract power and peak power for the last 5 years of each customer for 461 general customers as to AMR. In this dissertation, it is necessary to analyze the key features and general trend from the investigated data. It made an analysis of the feature parameters, such as average, standard deviation, median, maximum, minimun and thus it was carried by the linear and nonlinear regression analysis. Therefore, this paper compared characteristics for a contract power conversion factor which is applied to estimate contract power with characteristics for a regression model for customers(office, store, hotel, hospital, wedding hall) which maximum utilization factor of transformer is more than 60[%].

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2010.06a
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• pp.149-152
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• 2010

본 논문은 지구공간에 존재하는 다양한 공간정보를 이용하여 도로 및 철도 계획과 공사를 위한 최적노선을 선정하는 기법에 관한 새로운 연구이다. 사람과 물자를 수송하는데 있어서 가장 기본적인 공공교통시설인 도로 및 철도를 건설하기 위하여 초기에 가장 중요한 결정이 바로 최적노선결정이므로 환경파괴를 최대한으로 감소시키고 그 기능을 충분히 발휘할 수 있도록 대상 지역의 여러 가지 조건을 고려하여 가장 적합한 노선의 위치를 결정하여야 한다. 3차원 지형 환경의 공간영상콘텐츠는 국토계획 및 통신설비계획, 철도건설, 시공, 입체적인 유비쿼터스 도시 구현, 안전 및 방재 등에서 많은 요구와 그 중요성이 크게 부각되고 있다. 현재 지리정보 기반의 2차원적인 지도정보와 시설정보를 다차원의 도시공간으로 재현하기 위하여 기존의 등고선을 이용한 DEM 방식은 많은 한계를 가지고 있으며, 특히, 철도와 같은 노선 폭이 좁고 길이가 길어서 궤적 관리가 어려운 작은 구조물의 경우에는 그 고도모델이 무시되기 쉬우므로, 레이저 측량 기술을 이용한 공간대상물에 대한 높은 정확도 취득이 크게 필요한 실정이다. 본 연구에서는 원격탐사 영상 Data를 중심으로 하는 정사보정하고 이에 매칭 할 수 있는 수치 지도 벡터와의 통합 및 전환으로 다차원 공간에서 건물 모델의 생성과 다양한 활용을 제시하는 것을 연구목적으로 하였고, 연구방법으로는 기존의 이미 취득한 2차원적인 평면사진을 지상 기준점에 의하여 정밀기하보정을 하여 얻은 사진영상자료를 이용하여 3차원 공간정보로 구성하기 위해서는 동일지역에 대한 수준 측량결과인 높이 데이터를 매칭하여야 하므로, 항공기에 탑재한 센서로 모든 대상지에 대한 지형지물의 고밀도의 높이 값을 획득하여 위치보정 작업 후에 3D로 매칭할 수는 방법을 연구하여 실험하도록 하였다 또한 본 연구에서는 연구대상지역의 지형조건, 기존 노선과의 비교, 토지이용, 지형경사, 사면방향, 지가 등을 분석하여 각각의 경중률을 고려한 후 선택된 후보노선들을 비교분석함으로서 최적노선을 선정하고자 하였다.

• Journal of the Korea Society for Simulation
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• v.18 no.2
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• pp.19-27
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• 2009

This paper addresses the berth allocation problem in naval ports. Navy vessels need various services such as emergency repair, missile loading, oil supply and many others while commercial vessels only unload and load container at the port. Furthermore, naval vessels have to shift frequently due to a limited capacity of the port. The objective of this paper is to minimize the total number of nesting vessels at the naval port. In other word, the objective is to maximize the total number of naval battleships engaging in the sea. A mixed integer programming(MIP) model is developed and experiments are conducted with ILOG CPLEX 11.0. We compare the computational results of the MIP model to the current scheduling approach by the ROK Navy. The results showed that MIP model performed well by minimizing the number of nesting vessels. and avoiding unnecessary shifts.