• Title/Summary/Keyword: combined systems

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Analysis of Earth Continuity Conductor Installation Effect According to Fault Section in Combined Transmission Systems (혼합송전계통에서 고장구간에 따른 병행지선 설치효과 검토)

  • Kang, Ji-Won;Jung, Chae-Kyun;Park, Hung-Sok;Jang, Tai-In;Yoon, Hyung-Hee
    • Proceedings of the KIEE Conference
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    • 2008.11a
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    • pp.110-112
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    • 2008
  • This paper describes the effects of earth continuity conductor for reducing the level of induced sheath overvoltage at the single point bonded section of combined transmission systems. Firstly, 3 kinds of fault section are considered, and also faulty phases and the distance between phase conductor and earth continuity conductor are changed for the various analysis.

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Advanced Railway Power Quality Detecting Algorithm Using a Combined TEO and STFT Method

  • Yoo, Je-Ho;Shin, Seung-Kwon;Park, Jong-young;Cho, Soo-Hwan
    • Journal of Electrical Engineering and Technology
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    • v.10 no.6
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    • pp.2442-2447
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    • 2015
  • Because an electric railway vehicle is a large scale moving load, it can cause various kinds of power quality problems in the railroad power system. The power quality impacts are considered as the strong instantaneous stresses to the related power systems and can cause an accelerating aging and a malfunction of the power supplying components. Therefore, it is necessary to detect the small and intermittent symptoms mixed in the voltage waveform. However, they cannot be detected by the triggering functions of the existing power analyzers installed in the railway systems. This paper will examine the drawback of some fast detection tools and propose an advanced detecting and analyzing method based on a combined TEO and STFT algorithm.

Performance Improvement of Evolution Strategies using Reinforcement Learning

  • Sim, Kwee-Bo;Chun, Ho-Byung
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.1 no.1
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    • pp.125-130
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    • 2001
  • In this paper, we propose a new type of evolution strategies combined with reinforcement learning. We use the variances of fitness occurred by mutation to make the reinforcement signals which estimate and control the step length of mutation. With this proposed method, the convergence rate is improved. Also, we use cauchy distributed mutation to increase global convergence faculty. Cauchy distributed mutation is more likely to escape from a local minimum or move away from a plateau. After an outline of the history of evolution strategies, it is explained how evolution strategies can be combined with the reinforcement learning, named reinforcement evolution strategies. The performance of proposed method will be estimated by comparison with conventional evolution strategies on several test problems.

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Local stereo matching using combined matching cost and adaptive cost aggregation

  • Zhu, Shiping;Li, Zheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.1
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    • pp.224-241
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    • 2015
  • Multiview plus depth (MVD) videos are widely used in free-viewpoint TV systems. The best-known technique to determine depth information is based on stereo vision. In this paper, we propose a novel local stereo matching algorithm which is radiometric invariant. The key idea is to use a combined matching cost of intensity and gradient based similarity measure. In addition, we realize an adaptive cost aggregation scheme by constructing an adaptive support window for each pixel, which can solve the boundary and low texture problems. In the disparity refinement process, we propose a four-step post-processing technique to handle outliers and occlusions. Moreover, we conduct stereo reconstruction tests to verify the performance of the algorithm more intuitively. Experimental results show that the proposed method is effective and robust against local radiometric distortion. It has an average error of 5.93% on the Middlebury benchmark and is compatible to the state-of-art local methods.

Robust Predictive Control of Robot Manipulators with Uncertainties (불확실 로봇 매니퓰레이터의 견실 예측 제어기 설계)

  • 김정관;한명철
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.1
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    • pp.10-14
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    • 2004
  • We present a predictive control algorithm combined with the robust robot control that is constructed on the Lyapunov min-max approach. Since the control design of a real manipulator system may often be made on the basis of the imperfect knowledge about the model, it is an important trend to design a robust control law that guarantees the desired properties of the manipulator under uncertain elements. In the preceding robust control work, we need to tune several control parameters in the admissible set where the desired stability can be achieved. By introducing an optimal predictive control technique in robust control we can find out much more deterministic controller for both the stability and the performance of manipulators. A new class of robust control combined with an optimal predictive control is constructed. We apply it to a simple type of 2-link robot manipulator and show that a desired performance can be achieved through the computer simulation.

Modeling and Switching Overvoltage Analysis for Reclosing Analysis in Combined Transmission Systems (혼합송전계통에서 재폐로 해석을 위한 모델수립 및 개폐과전압해석)

  • Lim, Kwang-Sik;Lee, Jong-Beom;Kang, Ji-Won;Jung, Chae-Kyun
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.442-443
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    • 2008
  • This paper describes modeling using the EMTP/ATPDraw for reclosing analysis in 154kV combined transmission systems, and analyzes switching overvoltage. Current transformer established at lead-in area and lead-out area in transmission line and circuit breaker were modeled using TACS in the EMTP/ATPDraw. And also MODELS was constructed by signal processing of the operating reclosing. The simulation was carried out the switching overvoltage according to the length of overhead and underground transmission line, overvoltage between sheath and earth, and voltage between joint boxes.

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Docking System for Unmanned Underwater Vehicle using Reduced Signal Strength Indicator (전자기파의 감쇄신호를 이용한 무인 잠수정의 도킹시스템 개발)

  • Lee, Gi-Hyeon;Kim, Jin-Hyun
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.9
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    • pp.830-836
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    • 2012
  • According to increasing the importance of underwater environments, the needs of UUV are growing. This paper represents the mechanism and algorithm of UUV docking system with 21-inch torpedo tubes for military submarines as a docking station. To improve the reliability of the docking, torpedo tubes launch a wired ROV and next the ROV combined with UUV is retrieved. For estimating the relative position between the ROV and UUV, in this paper, combining RF sensors and vision system is proposed. The RSSI method of RF sensors is used to estimate the distance and the optical image is combined for the directional information.

Pulsed Actuator with Combined Plunger Made of Carbon Steel and Permanent Magnet

  • Dolezel, Ivo;Panek, David;Ulrych, Bohus
    • Journal of international Conference on Electrical Machines and Systems
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    • v.1 no.3
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    • pp.282-288
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    • 2012
  • A special pulsed electromagnetic actuator is presented whose plunger consists of two parts made of carbon steel and permanent magnet, respectively. The actuator exhibits a high holding force and small consumption of energy. The movement of the plunger is controlled by short current pulses. The static characteristics and other operation properties of the device are modeled numerically.

Fault Types-Classification and Section Discrimination Algorithm using Neuro-Fuzzy in Combined Transmission Lines (뉴로-퍼지를 이용한 혼합송전선로에서의 고장종류 및 고장구간 판별 알고리즘)

  • Kim, Kyoung-Ho;Lee, Jong-Beom
    • Proceedings of the KIEE Conference
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    • 2003.07a
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    • pp.534-536
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    • 2003
  • It is important to classily fault types and discriminate fault section by any detecting technique for combined transmission lines. This paper proposes the technique to classify the fault types and fault section using neuro-fuzzy systems. Neuro-fuzzy systems are composed of two parts to perform different works. First, neuro-fuzzy system for fault type classification is performed with approximation coefficient of currents obtained by wavelet transform. Another neuro-fuzzy system discriminates the fault section between overhead and underground with detail coefficients of voltage and current. In this paper, neuro-fuzzy system shows the excellent results for classification of fault types and discrimination of fault section.

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Kinematic Analysis and Motion Implementation of a Humanoid Robot with a Serial and Parallel Structure (직렬.병렬 혼합구조의 휴머노이드 상체로봇의 기구학 해석 및 움직임 구현)

  • Bae, Yeong-Geol;Jung, Seul
    • Journal of Institute of Control, Robotics and Systems
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    • v.15 no.9
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    • pp.952-958
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    • 2009
  • This article presents a combined structure of serial and parallel mechanisms for a humanoid robot. The 3 DOF parallel structure is designed and added to the waist of the humanoid robot arm to give flexible bending and rotating motions. Forward and inverse kinematics of a serial and parallel robot have been analyzed to generate motions. Simulation studies of verifying kinematics solutions of the parallel robot have been done. Experimental studies of mimicking shake-hands motion have been conducted to show the feasibility and usability of the combined structure.