• 제목/요약/키워드: client-server systems

검색결과 489건 처리시간 0.026초

인트라넷 환경에서 전자문서관리시스템 설계 및 구현 (Design and Implementation of an Electronic Document Management System in Intranet Environment)

  • 박창서;고형화
    • 전자공학회논문지C
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    • 제36C권10호
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    • pp.1-7
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    • 1999
  • 정보화시대가 도래함에 따라 기존의 종이문서 관리방식이 전자문서 관리방식으로 변하고 많은 응용 프로그램들이 인트라넷 기술을 사용하여 업무 효율을 높이고 있다. 본 논문은 인트라넷 환경에서 전자문서관리시스템의 설계 및 구현에 관한 것으로 사용자 및 일반관리자 시스템은 Internet Explorer 4.0을 기반으로 구현하여 하드웨어 특성에 따라 영향을 받던 클라이언트 시스템의 문제점을 해결하였다. 별도의 디바이스 드라이버가 필요한 스캔 스테이션과 전자문서관리시스템 서버는 TCP/IP를 통한 클라이언트/서버 시스템으로 구현하였다. 대용량의 데이터를 저장하는 주크박스는 표준 SCSI-ll를 지원하는 API를 구현하고 GUI는 Motif를 이용하여 구현함으로서 호환성과 편리성을 높였다.

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An Expanded Patching Technique using Four Types of Streams for True VoD Services

  • Ha, Sook-Jeong;Bae, Ihn-Han;Kim, Jin-Gyu;Park, Young-Ho;Oh, Sun-Jin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제3권5호
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    • pp.444-460
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    • 2009
  • In this paper, we propose an expanded patching technique in order to reduce the server network bandwidth requirements to support true VoD services in VoD Systems. Double Patching, which is a typical multicast technique, ensures that a long patching stream delivers not only essential video data for the current client but also extra video data for future clients. Since the extra data may include useless data, it results in server network bandwidth wastage. In order to prevent a server from transmitting useless data, the proposed patching technique uses a new kind of stream called a linking stream. A linking stream is transmitted to clients that have received short patching streams, and it plays a linking role between a patching stream and a regular stream. The linking stream enables a server to avoid transmitting unnecessary data delivered by a long patching stream in Double Patching, so the server never wastes its network bandwidth. Mathematical analysis shows that the proposed technique requires less server network bandwidth to support true VoD services than Double Patching. Moreover, simulation results show that it has better average service latency and client defection rate compared with Double Patching.

객체 복제 기법에 의한 원격 접근 알고리즘 (The Remote Access Algorithm by Object Replication)

  • 윤동식;이병관
    • 한국정보처리학회논문지
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    • 제7권3호
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    • pp.799-807
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    • 2000
  • In this paper, object replication Client/server under distributed computing system is design and implementation. Today many end-users have a computer communication by using internet in the distributed system of client/server. If many users request services to a specific remote server, the server should have got a overhead for hat service processing, delayed the speed for replay, and bring a bottleneck in communication network. Therefore object replication method was proposed to solve this problems. The growth of internet works and distributed applications has increased the need for large scale replicated systems. However, existing replication protocols do not address scale and autonomy issues adequately. Further, current application protocol require consistency of different levels, and therefore should be the selection function of consistency in them, in order to have particular semantics of each level. In this paper, server overhead and bottleneck happening in remote procedure call be using server object replication. Therefore access transparency can be improved by sharing object duplicately. So it will Keep up with the consistency within the replicated objects.

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효과적인 협업을 위한 VNC 확장 (Extending VNC for Effective Collaboration)

  • 이태호;이홍창;박양수;이명준
    • 한국컴퓨터정보학회논문지
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    • 제13권6호
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    • pp.181-193
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    • 2008
  • VNC는 Thin Client 컴퓨팅시스템의 하나로서 RFB(Remote Frame Buffer) 프로토콜을 통하여 서로 다른 플랫폼간의 원격 제어 기능을 지원한다. 그러나 VNC는 협업을 위하여 특별한 기능을 제공하지 않기 때문에 VNC의 원격 제어 기능을 통하여 효율적인 협업을 진행하는 것은 어려운 일이다. 본 논문에서는 오픈소스 VNC인 UltraVNC 서버와 JavaViewer 클라이언트의 확장에 대하여 기술한다. 효과적인 실시간 협업을 지원하기 위하여 확장된 VNC는 협업 서버를 제어하기 위하여 관리자, 작업자, 관람자와 같은 세가지 접근 권한을 제공한다. 관리자는 확장된 JavaViewer에서 새롭게 제공되는 접근 관리 도구를 통하여 권한 관리를 수행할 수 있다. 작업자는 협업서버의 자원을 제어하는 것이 가능하지만, 관람자는 협업서버의 자원을 제어 하는 것은 불가능하며 작업 진행사항을 단지 모니터링할 수 있다. 또한 확장된 VNC는 여러 협업참여자가 간편하게 협업서버에 접속할 수 있도록 원클릭 접속 기능을 제공한다.

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시스템 성능 향상을 위한 VoD서버의 능동 스케줄링 알고리즘 개발 (Developing Dynamic Scheduling Algorithm of VoD Server Server System Performance)

  • 김정택;고인선
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.65-65
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    • 2000
  • For Video on Demand(VoD) servers, a design of an efficient scheduler is important to the support a large number of clients having various playback speeds and receiving rates. In this paper, we propose the scheduling algorithm to handle establishing deadlines and selection using the earliest deadline first. To establish deadlines and selections, the period of the receiving rates for each client is located between the over-max receiving rate and the over-playback rate. To avoid video starvation and the buffer overflow of each client, the proposed algorithm guarantees providing the admission control. Because of establishing deadlines and selection, period of each client receiving is between one over max receiving rate and one over play back rate. Using Virtual Buffer in server, scheduling load is reduced. The efficiency of the proposed algorithm is verified using a Petri Net_Based simulation tool, Exspect.

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인터넷을 이용한 자율운행로봇의 원격운용 (Internal Teleoperation of an Autonomous Mobile Robot)

  • 박태현;강근택;이원창
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.45-45
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    • 2000
  • This paper proposes a remote control system that combines computer network and an autonomous mobile robot. We control remotely an autonomous mobile robot with vision via the internet to guide it under unknown environments in the real time. The main feature of this system is that local operators need a World Wide Web browser and a computer connected to the internet communication network and so they can command the robot in a remote location through our Home Page. The hardware architecture of this system consists of an autonomous mobile robot, workstation, and local computers. The software architecture of this system includes the server part for communication between user and robot and the client part for the user interface and a robot control system. The server and client parts are developed using Java language which is suitable to internet application and supports multi-platform. Furthermore, this system offers an image compression method using motion JPEG concept which reduces large time delay that occurs in network during image transmission.

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인터넷을 통한 원격 자재취급에 관한 연구 (Remote Material Handling Through Internet)

  • 김석호;한영근;박강;강경식
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2002년도 추계학술대회
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    • pp.157-163
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    • 2002
  • Automated manufacturing systems are applied to shop floors as a tool for the increase of productivity and quality and the decrease of manufacturing lead times and industry accidents. One of the most important issue of the present day is the application of Internet. The development of Internet technologies makes manufacturing enterprises break spacial barriers between users and shop floors, and collect various field data in remote sites. In this research, an Internet-based remote control system for a small-sized automated storage and retrieval system is developed for the purpose of real-time monitoring and control of automatic production equipment. The developed system has a client-server architecture and transmits real-time images of the automated storage and retrieval system to a client by ar CCD camera connected to a server. Based on the transmitted images, the client sends commands to PLC of the server, and part storage and retrieval tasks are executed.

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침입탐지 모듈을 이용한 역추적시스템 개발 (Development of Traceback System Using IDS Module)

  • 김선영;구향옥;서동일;오창석
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2003년도 춘계종합학술대회논문집
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    • pp.227-230
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    • 2003
  • 본 논문에서는 크래커가 여러 곳의 시스템을 경유하여 침입을 하였을 경우, 크래커의 경로를 역추적하기 위한 효율적인 역추적 모델을 제안하고 구현하였다. 구현한 역추적 시스템은 역추적 서버 모델, 역추적 클라이언트 모델로 구성된다. 역추적 클라이언트는 에이젼트가 설치된 곳에서 침입관련 정보를 역추적 서버로 전송하여 크래커가 침입의 경유지로 어느 시스템을 이용하였는지를 판별한다. 구현한 역추적 시스템으로 클라이언트 에이젼트가 설치된 곳에서는 효율적인 역추적 경로를 추적할 수 있었다.

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