• 제목/요약/키워드: Application protocol

검색결과 1,507건 처리시간 0.028초

A Study on the Delivery Systems of Teaching and Learning Contents for Education System Reform of Developing Countries

  • Kim, Myong-Hee;Park, Man-Gon
    • 한국멀티미디어학회논문지
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    • 제14권3호
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    • pp.471-479
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    • 2011
  • The world has witnessed a phenomenal growth in information and communication technologies (ICT). The development of new broadband communication services convergence of telecommunication with computers and recent developments in the field of communication protocol have fostered challenges as well as offerings in the wide-ranging use of ICT to support the creation of dynamic and interactive teaching and learning environment. By emergence of ICT, most of education and training institutions are struggling to integrate ICT and education and training systems. It is so important to apply proper delivery systems for utilization of the computerized teaching and learning contents in the classrooms. It will be a preliminary activity for building open and flexible distance teaching and learning systems in developing countries. In this paper, we would like to suggest and recommend the proper delivery systems for utilization of the computerized teaching and learning contents in the classrooms for education sector reform in developing countries.

Distributed CoAP Handover Using Distributed Mobility Agents in Internet-of-Things Networks

  • Choi, Sang-Il;Koh, Seok-Joo
    • Journal of information and communication convergence engineering
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    • 제15권1호
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    • pp.37-42
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    • 2017
  • The constrained application protocol (CoAP) can be used for remotely controlling various sensor devices in Internet of Things (IoT) networks. In CoAP, to support the handover of a mobile sensor device, service discovery and message transmission needs to be repeated, although doing so would increase the handover delay significantly. To address this limitation of CoAP, a centralized CoAP scheme has been proposed. However, it tends to result in performance degradation for an inter-domain handover case. In this letter, we propose a distributed CoAP handover scheme to support the inter-domain handover. In the proposed scheme, a distributed mobility agent (DMA) is used for managing the location of mobile sensors in a domain and performing handover control operations with its neighboring DMAs in a distributed manner. A performance comparison reveals that the proposed scheme offers a performance improvement of up to 29.5% in terms of the handover delay.

CAN 기반 휴머노이드 로봇에서의 데이터 프레임 최소화 (Minimizing Data Frame in CAN Controller Area Network for Humanoid Robot)

  • 권선구;허욱렬;김진걸
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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    • pp.2806-2808
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    • 2005
  • The Controller Area Network (CAN) is being widely used for real-time control application and small-scale distributed computer controller systems. When the stuff bits are generated by bit-stuffing mechanism in the CAN network, it causes jitter including variations in response time and delay. In order to eliminate this jitter, stuff bit must be controlled to minimize the response time and reduce the variation of data transmission time. At first, this paper shows that conventional CAN protocol causes the transmission time delay. Secondly, this paper proposes the method to reduce the stuff bits by restriction of available identifier. Finally, data manipulation method can be reduced the number of stuff-bits in the data field. The proposed restriction method of ID and manipulating data field are pretty useful to the real-time control strategy with respect to performance. These procedures are implemented in local controllers of the ISHURO (Inha Semyung Humanoid Robot).

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IEC61850 기반 디지털 변전시스팀에서의 PDMS 적용 방안에 관한 연구 (A study for PDMS Application Scheme of Digital S/S with IEC61850 Base)

  • 이동철;김희수;배을록;민병운
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 춘계학술대회 논문집 전기설비전문위원
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    • pp.78-82
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    • 2006
  • The Partial Discharge Monitoring System is technology which is available to measure & analysis the partial discharge of Power equipment. This technology is in the limelight as a pre-forecast system of equipment defect but there are some problems like no protocol standard, layered network management and the limitation of physical size. This paper presents whole system structure includes engineering centers, LN(Logical Node) to apply PDMS for, base-digital substation system, ICE61850 compatible Condition Monitoring &Diagnosis (CMD), Local Unit(LU), Intelligent Electronic Device (IED) for the solution scheme of these limitations.

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WAP 서비스를 이용한 ETC 인증 및 과금 결제 시스템 설계 (Design of ETC Authentication and Toll Charging System using WAP Service)

  • 조재만;신송아;유선영;임재홍
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2003년도 춘계학술발표논문집 (중)
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    • pp.767-770
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    • 2003
  • 현재 사용되고 있는 ETCS(Electronic Toll Collection Services)는 충전식의 스마트 카드와 카드리더를 이용하여 필요한 정보를 읽음으로 인증 및 과금 결제를 처리하는 방식이다. 혀 방식은 스마트 카드 규격이 다양하여 사용자는 각 규격에 맞는 카드리더를 사용해야 한다. 게다가 충전식이기 때문에 매번 충전해야하는 불편함이 있다. 본 논문에서는 현 ETC(Electronic Toll Collection)시스템의 단점을 극복하고자 스마트 카드 대신 휴대폰과 WAP(Wireless Application Protocol) 서버를 사용하여 통행료 자동징수 시스템을 설계한다. 또한 휴대폰을 사용함으로써 ITS(Intelligent Transfer Service) 시스템과 별도로 지역적인 인증이 가능하여 인중절차를 간소화시킬 수 있으며, ITS 시스템의 부하를 줄일 수 있기 때문에 ETC시스템 처리속도 또한 증가시킬 수 있다.

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VIRTUAL TELEMATICS SERVICE PROVIDER SYSTEM

  • Jang, In-Sung;Lee, Jun-Wook
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.836-839
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    • 2006
  • Telematics, one of the so-called New Growth Engine of IT839, is a leading IT service where wireless internet service represented by information and mobility is extended to the area of transportation. To provide telematics service, Telematics service provider have to connect with various Contents Provider or Service Provide server - for example - LBSS(Location Based Service Server), ASPS(Application Service Provider Server), TELICS(TELematics Information Center Server), GMS(Geo-mobility Server), WTPS(World Telematics Protocol Server) and MAUS(Map Air Update Server). Presently, It is nearly impossible or very difficult for the company that are manufacturing and testing telematics device to develop and test telematics solution without connecting Telematics Service Provider, Service Provider, Contents Provider. And, it is very difficult to connect in TSP, CP, SP having the product to be developed. In this paper, we proposed virtual telematics service provider. The proposed Virtual Telematics Service Provider is to provide telematics services and functionalities by integrating telematics servers into TSP gateway virtually. In other words, VTSP is performs with the role of TSP, CP, SP. And the VTSP support integration of telematics servers, interfacing and monitoring between terminal and the integrated servers.

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센서 네트워크에서 선택적 전달 공격 방어를 위한 GPSR 프로토콜 적용 (Application of GPSR Protocol for Countering Selective Forwarding Attacks in Sensor Networks)

  • 문수영;이민정;조대호
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2013년도 제48차 하계학술발표논문집 21권2호
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    • pp.51-54
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    • 2013
  • 센서 네트워크는 주변의 환경 정보를 수집하여 사용자에게 제공함으로써 지능적인 처리를 가능하게 하는 시스템이다. 센서 네트워크를 구성하는 센서 노드들은 메모리, 연산 능력, 에너지 등 자원 측면에서 제약을 갖고 있으며 무선 통신을 사용하므로 센서 네트워크 환경에서는 각종 보안 위협이 발생할 수 있다. 선택적 전달 공격에서 네트워크 내의 훼손 노드는 자신을 지나는 이벤트 보고서 중 전체 또는 일부를 제거함으로써 중요한 이벤트 정보가 싱크 노드까지 도달하지 못하도록 한다. 선택적 전달 공격을 방어하기 위한 기존 라우팅 기법은 많은 에너지 소비를 유발한다는 단점이 존재한다. 본 논문에서는 지형 기반의 라우팅 프로토콜인 Greedy Perimeter Stateless Routing (GPSR) 프로토콜을 기반으로 선택적 전달 공격 발생 지점을 우회할 수 있는 방법을 제안한다. 제안 기법은 선택적 전달 공격이 발생하는 환경에서 에너지 효율적으로 소스 노드에서 기지 노드까지 이벤트 보고서를 신뢰성 있게 전달하는데 활용될 수 있다.

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PDA 기반 포터블 진동 신호 분석기 개발 (Development of a Portable Device based on PDA for Vibration Signal Analysis)

  • 김동준;박광호;기창두
    • 한국정밀공학회지
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    • 제19권12호
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    • pp.179-184
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    • 2002
  • In this study, we developed a portable device which can monitor and analyze vibration signals from machines. This system consists a PDA loading the program for vibration analysis and A/D board for vibration acquisition. A PDA is smaller than the palm of the hand, but it has a powerful computing ability as much as an IBM compatible PC with a Pentium 100MHz CPU. The A/D board developed in this study supports LAN interface using TCP/IP communication protocol. The application program for vibration analysis includes signal processing module, fault diagnosis module, data store module, and plot display module. MS visual embedded C++ 3.0 was used to developed the program.

A New Algorithm Design for the Real-time Electrochemical Impedance Monitoring System

  • Chang, Byoung-Yong
    • Journal of Electrochemical Science and Technology
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    • 제3권4호
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    • pp.154-158
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    • 2012
  • It is generally known that electrochemical impedance spectroscopy is a powerful technique and its real-time application has been demanded for prompt observations on instantaneous electrochemical changes. Nevertheless, long measurement time and laborious analysis procedures have hindered development of it. Solving the problems, here I report of a new algorithm design for development of a real-time electrochemical impedance monitoring system, which potentially provides a guideline in developing monitoring systems of electric vehicles batteries and other electrochemical power plants. The significant progress in this report is employment of the parallel processing protocol which connects independent sub functions to successfully operate with avoiding mutual interruptions. Therefore, all the processes required to monitor electrochemical impedance changes in realtime are properly operated. To realize the conceptual scheme, a Labview program was coded with sub functions units which conduct their processes individually and only data are transferred between them through the parallel pipelines. Finally, measured impedance spectra and analysis results are displayed, which are synchronized according to the time of change.