• Title/Summary/Keyword: Channel management

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Tasks of Agricultural Extension in Korea;with special reference to cooperative agricultural extension services in the united states and it's implication (우리나라 농촌지도사업의 과제;미국의 농촌지도사업이 주는 시사점을 중심으로)

  • Choe, Yeong-Chang;Kim, Sung-Soo
    • Journal of Agricultural Extension & Community Development
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    • v.5 no.1
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    • pp.123-132
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    • 1998
  • After late 1980s, new approach is needed for satisfying with people's various information needs and better quality of life on Korean extension service. The United States began modern extension service at first and has influenced many countries. Cooperative extension service has helped people practically by searching into people's problem and developing various channel to diffuse. Cooperative extension adopts changes in extension service environment and puts them to use. Based on the extension service in the United States, following recommendations were suggested; 1) carrying out extension service to meet the changing needs of people, 2) strengthening the extension function of agricultural Colleges, 3) review of cooperative agricultural research and extension, 4) developing programs and management, 5) accumulation agricultural information and utilizing them.

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Context-based Dynamic Channel Management for efficient context processing using Event Service (이벤트 서비스를 이용한 컨텍스트 기반 동적 채널 관리)

  • Youn, Young-Kwon;Youn, Hee-Yong
    • Proceedings of the Korean Information Science Society Conference
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    • 2005.11a
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    • pp.490-492
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    • 2005
  • 유비쿼터스 환경에서 사용되는 수 않은 분산 애플리케이션들은 이벤트 기반 기법을 이용한 비동기 통신을 필요로 한다. OMG에서 정의된 비동기 메시지 처리를 위해 정의된 CORBA 이벤트 서비스는 유연성 있는 이벤트 채널을 통하여 분산 오브젝트 간의 비동기 통신을 지원한다. 기존의 이벤트 서비스에서 이벤트 서비스를 제공하기 위해서는 사용자나 개발자에 의해 수동적으로 채널이 생성되며, 생성된 채널을 통하여 이벤트 서비스를 제공한다. 그러나, 수동적인 채널관리 시스템은 분산 애플리케이션이 제공하는 다양한 이벤트 서비스를 제공하기에 기능적 오버헤드를 가지고 있다. 본 논문에서는 동적 채널 생성 삭제 그리고 컨텍스트 기반의 채널 관리 구조를 제시하며, 제안된 구조의 이벤트 서비스의 시뮬레이션 결과는 기존의 이벤트 서비스의 이벤트 처리 시간보다 더 나은 결과를 보여준다.

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A Distributed Power Optimization Method for CDMA Cellular Mobile Systems Using an Adaptive Search Scheme

  • Lee, Young-Dae
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1982-1985
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    • 2003
  • Future cellular networks will mainly be driven by, high quality channels, high band with utilization, low power consumption and efficient network management. For a given channel allocation, the capacity and quality of communication of cellular radio systems using CDMA(Code Division Multiple Access) can be increased by using a transmitter power control scheme to combat the near-far problem. Centralized power control schemes or distributed ones to maximize the minimum signal-to-interference in each user of CDMA wireless network have been investigated. This paper has proposed a distributed power control algorithm, which employs an adaptive search scheme, in order to solve quickly the linear systems of equations for power update in CDMA cellular radio systems. The simulation results show that the proposed scheme has faster convergence rate than the typical bang-bang type of distributed power control algorithm, which has been much used as a reference algorithm in IS-95A and W-CDMA communication network.

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Performance Evaluation of Burst Scheduling Schemes for WDM Optical Burst Switching (WDM 광 버스트 스위칭을 위한 버스트 스케줄링 기법의 성능 평가)

  • 차윤호;소원호;노선식;김영천
    • Proceedings of the IEEK Conference
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    • 2000.11a
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    • pp.177-180
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    • 2000
  • Optical burst switching(OBS) is a new switching paradigm to supporting bursty traffic on the Internet efficiently. OBS separates burst level and control level. To handle data burst efficiently, the scheduling schemes in optical burst switching systems must keep track of future resource availability when assigning arriving data bursts to wavelength channels. In this paper, we evaluate the performance of three scheduling schemes which are called Horizon, Single-gap and Multiple-gap, as a basic study for the future research of Optical Internet. Thus, firstly, we analyze the trade-off between the performance and the processing overhead of each scheme. In addition, the performance of OBS system which uses Multiple-gap scheduling is evaluated in detail under various network size. We use simulation for performance evaluation in terms of burst loss rate(BLR), wavelength channel utilization and the number of management data.

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A Study for FIPA-OS Multi-Agent Framework in OSGi Service Platform

  • Lee, Hyung-Jik;Kang, Kyu-Chang;Lee, Jeun-Woo
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2003.09a
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    • pp.232-235
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    • 2003
  • In this paper, we implemented a FIPA-OS multi-agent framework bundle in OSGi Service Platform. FIPA-OS is an open agent platform for constructing FIPA compliant agent using mandatory components that required by all FIPA-OS agents to execution and optional components that FIPA-OS agent car optionally use. The platform supports communication between multiple agents and communication language which conforms to the FIPA standards. FIPA-OS framework bundle is composed of DE(Directory Facilitator), AMS(Agent Management System), ACC(Agent Communication Channel) and MTS(Message Transport System) bundle. These bundles installed in the OSGi service platform and their life cycle can be managed by the framework.

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All-IP Digital Convergence and Its Effect on the Evolution of the Media Industry (All-IP화 디지털융합 및 미디어산업의 진화 연구)

  • Chung, Suk-Kyun
    • Journal of Information Technology Applications and Management
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    • v.18 no.2
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    • pp.23-38
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    • 2011
  • The advance of All-IP digital convergence is now triggering fundamental changes in the media industry. This article analyzes the evolution of the media industry based on a value chain model, with a special emphasis placed on the impact of digital technology on the structure of media production, distribution, and consumption. As the Internet has evolved into an access channel for all forms of media, the boundaries of the media industry remain unclear and open thus enabling anyone to become a creator of media. Furthermore, the scope of media continues to become more dynamic as competition grows between older and more innovative forms of media. In this light, adapting to innovative technologies and more effectively meeting the needs of customers represent key factors for the continued evolution of the media.

Psychological Factors of Increase in Apple Consumption (사과 소비의 증가에 영향을 미치는 심리적 요인 분석)

  • Huh, Moo-Yul
    • Journal of the Korean Society of Food Culture
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    • v.26 no.1
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    • pp.80-85
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    • 2011
  • This study analyzed consumer attitude, habit strength, subjective norm, a pros evaluation, and intention to consume to estimate perceptible variables that affect apple consumption. Data were collected from 207 men and women through a selfadministrated questionnaire. A partial least squares regression was conducted as one of structural equation models to estimate and test hypotheses. The results showed that attitude, habit strength, and the pros evaluation affected the intention to consume apples, and that the intention increased apple consumption. The results also showed that some marketing strategies are needed to promote apple consumption and to make consumers change their intention, to develop habits for eating apples by changing their diets, and to impress upon them that apples are good for health. This can be interpreted as meaning that it is most important to understand consumer behavior, particularly consumer psychology, which is reflected in the recent trend of marketing that concentrates on meeting the consumer's needs rather than the producer's.

Estimation Instream Flow Incremental Methodology (IFIM)

  • Lee, Joo-Heon;Jeong, Sang-Man;Lee, Myung-Ho;Lee, Soo-Yong;Lee, Eun-Tae
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.52-59
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    • 2005
  • The goal of this project is to estimate the instream flow of the Han River Basin to ensure the adequate supply of suitable quality water for preservation and enhancement of aquatic ecosystems. A applied model is Physical Habitant Simulation System(PHABSIM) of Instream Flow Incremental Methodology(IFIM). The parameters which are needed to simulation by PHABSIM such as flow depth, velocity distribution and channel cover with cross section data are obtained by field survey. The Habitat Suitability Criteria with the application of univariate curve on Zacco platypus as a target species was able to be established by conducting the field investigation. The estimated results of ecological recommended instream flow by this study has important meanings that the future river management have to seriously take into account for the natural environment and functions of river system.

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Relay Cooperative Transmission Scheme for an WiMedia based Shipboard Wireless Bridge (와이미디어기반 선내 무선 브릿지용 릴레이 협력통신 방식)

  • Jeon, Dong-Keun;Lee, Yeonwoo
    • Journal of Korea Multimedia Society
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    • v.17 no.6
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    • pp.687-696
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    • 2014
  • An integrated ship area network has functionality of remote control and autonomous management of various sensors and instruments embedded or boarded in a ship. For such environment, an wireless bridge is essential to transmit control and/or managing information to sensors or instruments from a central integrated ship area network station. In this paper, one of reliable schemes of WiMedia based wireless bridge using relay cooperative transmission using WiMedia distributed MAC protocol is proposed to increase a communication reliability between cluster headers, irrespective of channel variation. Simulation results show that the proposed wireless bridge using relay cooperative transmission scheme increases communication reliability.

Transient response of unit PEMFC with the visualization study of cathode flooding under different stoichiometries (당량비 조건에 따른 PEM단위 연료전지의 과도 응답 특성 및 공기극 플러딩 연구)

  • Cho, Jun-Hyun;Kim, Han-Sang;Min, Kyoung-Doug
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.06a
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    • pp.539-542
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    • 2007
  • The transient response of PEMFC (proton exchange membrane fuel cell) is important criteria in the application of PEM fuel cell to real automotive system. In this work, using a transparent unit PEM fuel cell, the transient response and cathode flooding during load change are investigated. The cell voltage is acquired according to the current density change($0.3Acm^2$ to $0.6A/cm^2$) under various stoichiometry conditions and different flooding intensities, Also the cathode gas channel images are obtained by CCD imaging system simultaneously. The different level of undershoots appeared at the moment of load changes under different cathode stoichiometries and flooding intensities. The correlation of the dynamic behavior with stoichiometry and cathode flooding is induced from the results of these experiments.

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