• Title/Summary/Keyword: Terminal distance

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A Non-Incremental Hierarchical Conference Organization Using Shortest Distance Terminal (최단 거리 단말기를 이용하는 비점진적 계층 회의 구성 방법)

  • Lee, Keonbae
    • Journal of IKEEE
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    • v.18 no.2
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    • pp.248-254
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    • 2014
  • The hierarchical conference causes the data delay because the exchanged data between terminals in the conference go through the hierarchical structure. In this paper, we propose an algorithm which minimizes the average path distance between terminals in a non-incremental hierarchical conference, and which considers the computing resource. For terminals which want to join the ongoing hierarchical conference, our algorithm selects terminals that the new connection is possible among terminals in the conference with the computing resource consideration. Then, after all distance values between the selected terminals and terminals which want to join the ongoing hierarchical conference are computed, and the terminal-pair which have minimum distance value is selected, the ongoing hierarchical conference is extended with a connection of the terminal-pair which consists of a terminal among selected terminals and other terminal among terminals which want to join the ongoing hierarchical conference. This continues until all terminals are included in the conference. As the experimental results with the proposed non-incremental scheme, the hierarchical conference can be organized with 24% better performance than the earlier incremental scheme on the basis of average path distance between terminals.

Optimizing Gate Assignment at Domestic Airport (공항터미널 주기장 배정의 최적화에 대한 연구)

  • 이희남;김연명;이공섭;이창호
    • Journal of the Korea Safety Management & Science
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    • v.4 no.4
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    • pp.129-136
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    • 2002
  • Utilization rate for the restrictive gate and required time and walking distance to board are to be a measure for the gate management and passenger's convenience estimation. So, the main purpose of the gate management are maximization of utilization rate and increment of airport terminal user's convenience through the efficient gate management. This study intends to maximize the utilization rate on usable gates and minimize the passenger's working distance in terminal by concerning about layout, terminal configuration, local passenger of the airport and formulate the gate assignment problem with integer linear programming problem. Then we obtained solution using optimization software LINGO and analyzed that maximize the number of assignment flights and minimize the passenger's walking distance.

The Real-Time Distance Relay Algorithm Using fault Location Estimation Information for Parallel Transmission Line (병행 2회선 송전선로에서 고장점 위치 추정정보를 이용한 실시간 거리계전 알고리즘)

  • 이재규;유석구
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.52 no.3
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    • pp.183-192
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    • 2003
  • This paper presents the real-time implemented distance relay algorithm which the fault distance is estimated with only local terminal information. When a single-phase-to-earth fault on a two-parallel transmission line occurs, the reach accuracy of distance relay is considerably affected by the unknown variables which are fault resistance, fault current at the fault point and zero- sequence current of sound line The zero-sequence current of sound line is estimated by using the zero sequence voltage which is measured by relaying location Also. the fault resistance is removed at the Process of numerical formula expansion. Lastly, the fault current through a fault point is expressed as a function of the zero-sequence current of fault line, zero-sequence current of sound line, and line, and fault distance. Therefore, the fault phase voltage can be expressed as the quadratic equation of the fault distance. The solution of this Quadratic equation is obtained by using a coefficient of the modified quadratic equation instead of using the square root solution method. After tile accurate fault distance is estimated. the mote accurate impedance is measured by using such an information.

A Fault Location Algorithm for a Single Line Ground Fault on a Multi-Terminal Transmission Line (다단자 송전계통에서의 1선지락 고장시 고장점 표정 알고리즘)

  • 강상희;노재근;권영진
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.52 no.2
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    • pp.121-133
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    • 2003
  • This paper presents a fault location algorithm for a single phase-to-ground fault on 3-terminal transmission systems. The method uses only the local end voltage and current signals. Other currents used for the algorithm are estimated by current distribution factors and the local end current. Negative sequence current is used to remove the effect of load current. Five distance equations based on Kirchhoff's voltage law are established for the location algorithm which can be applied to a parallel transmission line having a teed circuit. Separating the real and imaginary parts of each distance equation, final nonlinear equations that are functions of the fault location can be obtained. The Newton-Raphson method is then applied to calculate the estimated fault location. Among the solutions, a correct fault distance is selected by the conditions of the existence of solution. With the results of extensive S/W and H/W simulation tests, it was verified that the proposed algorithm can estimate an accurate fault distance in a 154kV model system.

A New One Terminal Numerical Algorithm for Adaptive Autoreclosure and Fault Distance Calculation (적응 자동 재폐로 및 고장거리 산정을 위한 새로운 1단자 알고리즘)

  • Zoran Radojevic;Joong-Rin Shin
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.53 no.8
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    • pp.438-445
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    • 2004
  • This paper presents a new numerical spectral domain algorithm devoted to blocking unsuccessful automatic reclosing onto permanent faults and fault distance calculation. Arc voltage amplitude and fault distance are calculated from the fundamental and third harmonics of the terminal voltages and currents phasors. From the calculated arc voltage amplitude it can be concluded if the fault is transient arcing fault or permanent arcless fault. If the fault is permanent automatic reclosure should be blocked. The algorithm can be applied for adaptive autoreclosure, distance protection, and fault location. The results of algorithm testing through computer simulation and real field record are given.

Computation of the Shortest Distance of Container Yard Tractor for Multi-Cycle System (다중 사이클 시스템을 위한 실시간 위치 기반 컨테이너 야드 트랙터 최단거리 계산)

  • Kim, Han-Soo;Park, Man-Gon
    • Journal of Korea Multimedia Society
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    • v.13 no.1
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    • pp.17-29
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    • 2010
  • A container terminal productivity is maximized by a minimized time for processing containers. So, we have been elevated the container terminal productivity through an improvement of computing system, but there are a limitation because of problems for transportation management and method. A Y/T(Yard Tractor), which is a representative transportation, is able to do only one process, loading or unloading, at one time. So if the Y/T can do loading and unloading step by step at a same time, the processing time would be shortened. In this paper, we proposed an effective operating process of Y/T(Yard Tractor) Multi-Cycle System by applying RTLS(Real Time Location System) to Y/T(Yard Tractor) in order to improve the process of loading and unloading at the container terminal. For this, we described Multi-Cycle System. This system consists of a real time location of Y/T based on RTLS, an indicating of Y/T location in real time with GIS technology, and an algorithm(Dijkstra's algorithm) of the shortest distance. And we used the system in container terminal process and could improve the container terminal productivity. As the result of simulation for the proposed system in this paper, we could verify that 9% of driving distance was reduced compared with the existing rate and 19% of driving distance was reduced compared with the maximum rate. Consequently, we could find out the container performance is maximized.

An Estimate of the Required Number of Yard Tractor in Container Terminal (컨테이너터미널의 야드 트랙터 소요대수 추정)

  • Choi, Yong-Seok;Kim, Woo-Sun;Ha, Tae-Young
    • Journal of Navigation and Port Research
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    • v.28 no.6
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    • pp.549-555
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    • 2004
  • The purpose of this study is to estimate the required number of yard tractor on port container terminal. The number of yard tractor is the bottleneck factor on the efficiency of container terminal. Due to the change in travel speed and travel distance, the efficiency is difficult to estimate. The efficiency of yard tractor is estimated by the proposed simulation model that developed considering the queueing network between container crane and transfer crane. The number of yard tractor per container crane is estimated by the alternative analysis. And to determine the number of yard tractor per container crane, the performance measure such as the distance between berth and yard, the speed of yard tractor are simulated.

Experimental Examinations on Protective Effects of SPDs Associated with the Protective Distance and Type of Load (보호거리와 부하 유형에 따른 SPD의 보호효과에 대한 실험적 고찰)

  • Lee, Bok-Hee;Kim, You-Ha;Ahn, Chang-Hwan
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.26 no.10
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    • pp.81-88
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    • 2012
  • Surge protective devices(SPDs) are widely used as a most effective means protecting the electrical and electronic equipment against overvoltages such as lightning and switching surges. When installing SPDs, it is essential that the voltage protection level provided by SPDs should be lower than the withstand voltage of the equipment being protected. But even the proper selection of SPDs are achieved, the voltage at the equipment terminal may be higher than the residual voltage of SPD due to the reflection and oscillation phenomena. This paper was focused on the investigations of the conditions for which the equipment is protected by an SPD taking into account the influences of the protective distance and type of load. The protective effects of SPD with voltage-limiting component were analyzed as functions of types of load and protective distance between the SPD and load. As a result, in the cases of long protective distances, capacitive loads and loads with high resistance, the voltage at the load terminal was significantly higher than the residual voltage of SPD. It was found that the proper installation of SPDs should be carried out by taking into account the protective distance and type of load to achieve reliable protection of electronic equipments against surges.

A Study on the Operational Characteristic of Distance Relay According to Power System Condition (계통조건에 의한 거리계전기의 응동특성에 관한 연구)

  • Jung, Chang-Ho;Kim, Jin-O
    • Proceedings of the KIEE Conference
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    • 2001.05a
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    • pp.290-293
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    • 2001
  • This paper presents the reach accuracy of a distance relay for protection of transmission line according to power system conditions. The apparent impedance of distance relay is considerably affected by source impedance, load current, power factor, fault point and resistance etc. For protective coordination on the variables power system parameters, trip characteristics of distance relay at sending and receiving terminal are discussed.

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Multi-layer Speech Processing System for Point-Of-Interest Recognition in the Car Navigation System (차량용 항법장치에서의 관심지 인식을 위한 다단계 음성 처리 시스템)

  • Bhang, Ki-Duck;Kang, Chul-Ho
    • Journal of Korea Multimedia Society
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    • v.12 no.1
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    • pp.16-25
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    • 2009
  • In the car environment that the first priority is a safety problem, the large vocabulary isolated word recognition system with POI domain is required as the optimal HMI technique. For the telematics terminal with a highly limited processing time and memory capacity, it is impossible to process more than 100,000 words in the terminal by the general speech recognition methods. Therefore, we proposed phoneme recognizer using the phonetic GMM and also PDM Levenshtein distance with multi-layer architecture for the POI recognition of telematics terminal. By the proposed methods, we obtained high performance in the telematics terminal with low speed processing and small memory capacity. we obtained the recognition rate of maximum 94.8% in indoor environment and of maximum 92.4% in the car navigation environments.

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