• 제목/요약/키워드: Terminal distance

검색결과 222건 처리시간 0.026초

위치관리를 위한 단말기 페이징 기법의 성능 분석 (Performance Analysis of Terminal Paging Strategies for Location Management)

  • 김규칠;최창열;김용석
    • 산업기술연구
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    • 제21권B호
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    • pp.257-263
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    • 2001
  • Terminal paging is the process of determining the exact location of a particular mobile terminal. The paging cost is related to the number of paging cycles and the number of cells being polled by each cycle. In this paper, we first analyze the performance of various terminal paging strategies in terms of the number of polling cycles and the number of polling signals. Then we present a paging scheme which combines Shortest-Distance-First with movement history list. Simulation results show that the proposed paging scheme reduces the number of polling signals as well as the number of polling cycles.

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염료감응형 태양전지의 광전극 확장에 따른 광전특성 연구 (A Study on The Photoelectric Characteristics of Dye-sensitized Solar Cell according to Expanding Photo-electrode)

  • 서현웅;김미정;박제욱;김호성;김희제
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2007년도 춘계학술대회
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    • pp.305-308
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    • 2007
  • The field of dye-sensitized solar cell (DSC) is being researched actively at present. Because DSC has several advantages to pass the limits of Si solar cells such as a low manufacturing expense, a simple manufacturing process and its transparency. A lot of researches are underway about materials and processes in the field of dye-sensitized solar cell but its structure has been fixed up as the sandwich structure that both edges are used as positive and negative terminals. But the structure as of present is a factor of decreasing efficiency because the more electrons are recombined the further distance from terminal, considering about the characteristic of dye-sensitized solar cell that electrons generated inside cell are moved by diffusion. In this study, we made experiment on expanding the terminal to shorten internal moving distance of electron and compared the results according to the variation of active area to find out the effect of this trial. As a result, we achieved about 15.5% improvement of maximum power and 0.5% improvement of efficiency from terminal-expanded dye-sensitized solar cell of $2cm^{2}$ active area and concluded that the increasing rate of efficiency is raised as the active area becomes wider.

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표적충돌각과 최대가속도 제한을 고려한 최적유도기법 (Optimal guidance with terminal impact angle and control constraint)

  • 류창경;조항주
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.601-606
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    • 1992
  • In this paper, we consider an optimal guidance problem with both the terminal impact angle and control constraints in addition to the usual zero miss distance constraint. We first present the optimal solution of the problem for the missile of an arbitrary order, and show that it is a linear combination of a step response and a ramp response of the missile. Therefore the usual practice of using the control obtained by saturating the optimal solution for the case of unlimited control may result in a large terminal miss. A method called the initial command saturation is suggested to reduce this terminal miss, where the control in the initial phase of guidance is forced to be saturated until a certain condition for a guidance variable is met.

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A Simulation Model for Improving the Productivity of Container Handling in the Container Terminal

  • Park, Nam-Kyu;Lee, Sang-Wan;Park, Hyung-Rim;Kwon, Hae-Kyoung
    • 한국항해항만학회지
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    • 제28권4호
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    • pp.285-291
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    • 2004
  • The productivity of container terminal is determined by its various operation methods. This paper aims at finding out the factors to enhance the productivity of container handling of quay crane, using simulation technique. Three levels of decision making in terminal operation, strategy, and tactics and operation are selected for defining parameters of simulation The result of the simulation and test shows that the significant factors to improve the productivity are the stack height of container, block dispersion and the distance in yard planning for shipment. Decision making in the operation level, however, is of significance in the mixed condition of strategic and tactical level. The result shows meaningful guidelines in decision making under strategic, tactical and operation level.

중단거리 화물운송시장에서의 철도물류 경쟁력 강화방안 (A Study on the increasing competitiveness of railway freight transportation in mid- or short- distance market)

  • 방연근;유재균;이순철
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2003년도 추계학술대회 논문집(II)
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    • pp.319-325
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    • 2003
  • This study focuses on the efforts of rail freight industry in Europe to adapt to the change of freight market. Nearly $80\%$ of freight is transported in short and medium distance market and due to e-commerce the freight becomes small and requires more frequencies than before. Rail freight industry tries to change their operation practices and to create measures to catch the market share. Trials in the two market segments, sea port to/from inland rail terminal and airport to/from inland rail terminal, are reviewed in this study.

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충돌 자세각 제한조건을 갖는 종단 유도를 위한 시변 편향 비례항법 (Time-varying biased proportional navigation for terminal guidance with impact attitude angle constraint)

  • 김병수;이보형;이장규;김삼수;조현진
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.355-358
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    • 1996
  • The primary objective of guidance system is to generate suitable commands so that the pursuer comes closer to its target. It is necessary, however, in the guidance of a certain pursuer that the attitude angle at impact should be within a prescribed range in addition to specification on the miss distance. These guidance requirements can not be satisfied by the general guidance laws developed for miss distance minimization. Compared with the demand in many applications, the guidance laws dealing with impact attitude angle constraint are not easily found. In this paper, biased PNG laws are proposed to obtain the guidance purposes. By Lyapunov method, it is shown that the pursuer can intercept the target with a prescribed attitude angle under the assumption that the pursuer is sufficiently fast and the target maneuver is negligible. The simulation results are presented to demonstrate the performance of the suggested guidance laws.

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지능형 주기장 배정을 위한 의사결정지원시스템 개발에 대한 연구 (A Study on the Development of Decision Support System for Intelligent Gate Assignment)

  • 이희남;최광억;이창호
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2001년도 추계학술대회
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    • pp.37-42
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    • 2001
  • 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 by concerning about layout, terminal configuration, local passenger of the airport and development of gate assignment algorithm and DSS which maximize the gate utilization and minimize the passenger's walking distance.

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지능형 주기장 배정을 위한 의사결정지원시스템 개발에 대한 연구 (A Study on the Development of Decision Support System for Intelligent Gate Assignment)

  • 이희남;김연명;이창호
    • 대한안전경영과학회지
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    • 제5권1호
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    • pp.93-102
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    • 2003
  • Utilization rate for the gate and required time and walking distance to boarding flight are important measures for the gate management and passenger's convenience estimation. So, the main purpose of the gate management are the maximization of utilization rate and improvement of airport terminal user's convenience through the efficient gate management. This study intends to maximize the utilization rate of usable gates by considering layout, terminal configuration, local passenger of the airport and development of gate assignment algorithm and DSS which maximizes the gate utilization and minimizes the passengers' walking distance. And the decision support system can provide an efficient means of airport management of airport using an assignment algorithm.

UHF RFID 모듈을 이용한 원거리 데이터 전송 전용단말기 개발 (The Development of Terminal for Long Distance Data Transmission Using UHF RFID Module)

  • 황기현
    • 한국정보통신학회논문지
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    • 제13권11호
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    • pp.2465-2472
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    • 2009
  • 본 논문에서는 ARM 칩(AT91SAM7S256), UHF/RF RFID R/W 모듈(WJR7090) 및 Bluetooth통신(FB755AC)을 이용하여 UHF RFID R/W에 적합한 원거리 데이터 전송 전용단말기를 개발하였다. 개발한 UHF RHID R/W 전용 단말기는 RFID Tag값을 Tagging하고 그 값을 Bluetooth를 통해서 서버로 전송하고, 전송한 RFID Tag값을 DB와 비교하여 그 결과를 단말기에 전송하였다. 개발한 전용단말기의 성능을 입증하기 위해 성능실험을 실시하였고, 개발한 단말기의 우수성 및 송수신패킷에 대한 실험 결과를 나타내었다.

Macro cell에서 Mobile IP를 고려한 Handover 과정 및 분석 (Handover Procedures and Analysis for Mobile IP in Macro cell)

  • 홍성화;노재성;정해원;조성준
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(1)
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    • pp.277-280
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    • 2001
  • Due to the explosive popularization of the Internet, it has been researched for many mobile terminals how to receive various multimedia information. Especially, it has been considered that a mobile terminal is serviced with multimedia information through a inherent IP address. In this paper we have proposed the Handover Signaling Method and analyzed the Handover delay time of this proposed method in wireless section. This proposed method is appropriate to Broadband systems with Mobile IP. We have simulated Handover delay time with respect to the distance between a terminal and base stations

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