• Title/Summary/Keyword: Dynamic Coordination

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Modeling of Hybride Electric Vehicle Drivetrain and Development of Simulation Program (하이브리드 전기차량 동력부의 모델링 및 성능평가 프로그램 제작)

  • 김도형;박영진
    • Transactions of the Korean Society of Automotive Engineers
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    • v.8 no.6
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    • pp.122-129
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    • 2000
  • This paper describes a hybrid dynamic system(HDS) modeling method and result for the drivertrain of a parallel hybrid electric vehicle(PHEV) which consists of a gasoline engine, an electric machine, and a continuous variable transmission (CVT) and proposes a drivetrain control system. The control system has an engine controller, a motor controller, a CVT controller and a supervisory controller for the coordination of all system. The controller keep the speed of engine wheel and the output torque within the optimal operation range based on the experimental data. We also developed a MATLAB/SIMULINK program for the performance simulation of PHEV drivetrain model and controllers and compared the simulation result with the experiment result in the recent literatures.

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The Role of Cytoskeletal Elements in Shaping Bacterial Cells

  • Cho, Hongbaek
    • Journal of Microbiology and Biotechnology
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    • v.25 no.3
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    • pp.307-316
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    • 2015
  • Beginning from the recognition of FtsZ as a bacterial tubulin homolog in the early 1990s, many bacterial cytoskeletal elements have been identified, including homologs to the major eukaryotic cytoskeletal elements (tubulin, actin, and intermediate filament) and the elements unique in prokaryotes (ParA/MinD family and bactofilins). The discovery and functional characterization of the bacterial cytoskeleton have revolutionized our understanding of bacterial cells, revealing their elaborate and dynamic subcellular organization. As in eukaryotic systems, the bacterial cytoskeleton participates in cell division, cell morphogenesis, DNA segregation, and other important cellular processes. However, in accordance with the vast difference between bacterial and eukaryotic cells, many bacterial cytoskeletal proteins play distinct roles from their eukaryotic counterparts; for example, control of cell wall synthesis for cell division and morphogenesis. This review is aimed at providing an overview of the bacterial cytoskeleton, and discussing the roles and assembly dynamics of bacterial cytoskeletal proteins in more detail in relation to their most widely conserved functions, DNA segregation and coordination of cell wall synthesis.

PC유통업체를 위한 창조적인 가격 방안 - PC 양판점을 중심으로

  • 권기대
    • Journal of Distribution Research
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    • v.2 no.1
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    • pp.183-195
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    • 1997
  • The liberalization of Korean distribution market will undoubtedly lead to some erosion of market share of indigenous distributors in PC GMS(General Merchandising Store) & all the industries, but to our surprising, the benefits of rationalization of distribution, high qualities & low prices, strengthened competitiveness of indigenous retailers far outweigh the costs. The aim of this paper is to present some basic executive ideas for achieving a more global competitiveness in the 21st century. That is, successful market responsiveness in our distributors & firms will first of all require Dynamic Supply Chain Management at the base of information infrastructure to obtain the best competitive power. Secondly, in practical perspectives, distributors & firms needs to learn precise analysis on the basis of customer needs & wants as well as flexible thinking & proactive attitudes with respect to an freezing markets. In conclusions, win-win strategy in the competition for existence has to retain continuous & close relationship between cooperation and coordination.

The Modified Backoff Algorithm to reduce the number of collisions in the IEEE 802.11 Networks

  • Nam, Jae-Hyun
    • Journal of information and communication convergence engineering
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    • v.6 no.2
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    • pp.228-232
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    • 2008
  • In recent years, wireless ad hoc networks have become increasingly popular in both military and civilian applications due to their capability of building networks without the need for a pre-existing infrastructure. Recently, IEEE 802.11 Task Group e has been working on a new mechanism, the Enhanced Distributed Coordination Function (EDCF), to enhance the performance of 802.11 DCF. However, EDCF only reduces the internal collisions within a station, and external collisions between stations remain high in ad-hoc networks. In this paper, we propose to adopt an adaptive backoff window control technique, based on a dynamic value of the initial value of the range in which the backoff is chosen, so the backoff timer is randomly chosen in the range (InitRng, CW-1). We use ns-2 simulation to evaluate the throughput of our scheme. Results show that the throughput is improved for our scheme compared to the original DCF due to the reduced the number of collisions.

The Analysis Results of Lightning Overvoltages by EMTP for Lightning Protection Design of 500kV Substations

  • Ju Hyung-Jun;Lee Heung-Ho
    • KIEE International Transactions on Power Engineering
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    • v.5A no.4
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    • pp.366-370
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    • 2005
  • To meet increasing power demand, 500 kV power systems are under consideration in the regions of some Middle Asian countries. As the power system voltage becomes higher, the cost for the power system insulation increases significantly. 500 kV transmission systems will become the basis of a region's power system and they require much higher system reliability. Consequently, by the methods of limiting overvoltages effectively, a reasonable insulation design and coordination must be accomplished. In particular, the Substations must be constructed to be of outdoor type. In order to determine the various factors for the insulation design, the EMTP (Electro-magnetic transient program) is used for the magnification of transient phenomena of the 500 kV systems in the planned network. In this paper, we will explain the calculation results of lightning overvoltages by the EMTP for lightning protection design for the 500 kV substations. To obtain reliable results, the multi-story tower model and EMTP/TACS model are introduced for the simulation of dynamic arc characteristics.

A Study of Distance Relay Characteristic of Transmission Line including FACTS Devices (FACTS 기기가 설치된 송전선로에서 거리계전기의 응동특성)

  • Jung, Chang-Ho;Suh, Jung-Nam;Bang, Seong-Won;Kim, Jin-O
    • Proceedings of the KIEE Conference
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    • 2000.07a
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    • pp.31-33
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    • 2000
  • This paper discusses the operational characteristic analysis of distance relay depending on the power system parameters in transmission line including FACTS devices. Distance relay requires protective coordination because the FACTS devices change power system parameters to increase power transmission capacity. In this paper, the dynamic operational characteristics of distance relay are analyed for the effect of fault resistance and operation mode of FACTS devices according to the installed points of these devices.

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Cooperative Interference Mitigation Using Fractional Frequency Reuse and Intercell Spatial Demultiplexing

  • Chang, Jae-Won;Heo, Jun;Sung, Won-Jin
    • Journal of Communications and Networks
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    • v.10 no.2
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    • pp.127-136
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    • 2008
  • For mobile wireless systems with full frequency reuse, co-channel interference near the cell coverage boundaries has a significant impact on the signal reception performance. This paper addresses an approach to efficiently mitigate the effect of downlink co-channel interference when multi-antenna terminals are used in cellular environments, by proposing a signal detection strategy combined with a system-level coordination for dynamic frequency reuse. We demonstrate the utilization of multi-antennas to perform spatial demultiplexing of both the desired signal and interfering signals from adjacent cells results in significant improvement of spectral efficiency compared to the maximal ratio combining (MRC) performance, especially when an appropriate frequency reuse based on the traffic loading condition is coordinated among cells. Both analytic expressions for the capacity and experimental results using the adaptive modulation and coding (AMC) are used to confirm the performance gain. The robustness of the proposed scheme against varying operational conditions such as the channel estimation error and shadowing effects are also verified by simulation results.

A Study of Cooperative Algorithm in Multi Robots by Reinforcement Learning

  • Hong, Seong-Woo;Park, Gyu-Jong;Bae, Jong-I1;Ahn, Doo-Sung
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.149.1-149
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    • 2001
  • In multi robot environment, the action selection strategy is important for the cooperation and coordination of multi agents. However the overlap of actions selected individually by each robot makes the acquisition of cooperation behaviors less efficient. In addition to that, a complex and dynamic environment makes cooperation even more difficult. So in this paper, we propose a control algorithm which enables each robot to determine the action for the effective cooperation in multi-robot system. Here, we propose cooperative algorithm with reinforcement learning to determine the action selection In this paper, when the environment changes, each robot selects an appropriate behavior strategy intelligently. We employ ...

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Crisis Communication Strategy for Responding the Disaster in North-East Asia: Enhancing the Cooperative Disaster Management Network and the Social Network

  • Lee, Jae-Eun
    • International Journal of Contents
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    • v.8 no.3
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    • pp.64-70
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    • 2012
  • The purpose of this paper is to give some crisis communication strategies for effective cooperation and coordination among the countries in global society. Based on the theoretical discussions, in this paper, five strategic recommendations toward improving crisis communication are offered as follows; First, it is necessary that a small, dynamic team for global crisis communication function be established among the nearby countries. Second, for understanding the neighboring country's crisis situation, it is needed that the common crisis communication organizations which play an important role of disseminating accurate information and giving the collaborative efforts in each country have to be made. Third, for effective crisis management, an appropriate infrastructure that includes open and effective communication channels among different levels and across organizations must be in place. Fourth, mass communication should fulfill a variety of functions in society and provide information, interpretation of events, and its influence, etc for cooperating and coordinating the crisis management. Fifth, to acquire a correct understanding of the bordering country's crisis and calamities, intercultural education program should be established in the crisis communication system.

A Study on the Semiotic Approach of Logo in Sportswear Brand (스포츠웨어 브랜드 로고의 기호학적 분석)

  • Lee, Min-Gyung
    • The Research Journal of the Costume Culture
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    • v.14 no.2
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    • pp.177-191
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    • 2006
  • The purpose of this study was to analyze the signification system between logo and brand concept systematically in sportswear brands. For this purpose, 37 apparel brands focused on sportswear brand were selected and the results of the study were following : First, the sportswear brands that symbolize a specific sports used a related supplies such as a golf ball or tennis ball, etc to express sports or concept that pursuit each brand. Second, the sportswear brands used the brand logo that represent or symbolize a specific animal, plant and natural world to express a strong spirit of sports and active energy. Third, the sportswear brands used the word mark or symbol that design a brand name in dynamic or speedy typeface to represent a speed and progressive spirit of sports. Fourth, the sportswear brands used the symbols that represent a concrete object, person such as a mast, shield, etc to emphasize the brand concept. Fifth, the sportswear brands used the symbols of a graphic or geometric style to represent the special quality of brand in type.

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