• 한국정보통신설비학회:학술대회논문집
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• 2003.08a
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• pp.229-233
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• 2003

최근, 인터넷 사용자가 급증하면서 빠른 서비스에 대한 문제가 큰 관심이 되고있다. 특히 데이터베이스 시스템에서 저장 삭세 수정 등은 사용자에게 긴 대기시간을 요구할 수도 있기 때문에 사용자의 불평을 야기할 수 있다. 이 논문에서는 3-티어 방식에서 요즘 많이 사용되는 application server의 cache에 대해서 말하고자 한다. 기존 application server는 데이터를 application server cache에 저장하여 같은 데이터를 서비스할 경우 server의 cache를 사용하지만 이 논문에서 제안하는 것은 접속된 client를 관리하여 각각의 client에 cache를 만들고 application server나 또는 데이터베이스 server가 서비스를 하지 못할 경우는 가장 최근의 데이터를 가지고 있는 client를 찾아 client cache에 있는 데이터를 서비스 하자는 것이다.

• Proceedings of the Korea Database Society Conference
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• 1994.09a
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• pp.49-69
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• 1994

A client/server system has become the computing architecture for the business organization which seeks competitive edges. Technically, a client/server system places application processing close to the user and thus increases performance. This paper's two primary goals are (i) to present a performance model for client/server database systems and (ii) to demonstrate analytically the effectiveness of client/server computing in comparison with other computing architectures via an illustrative example. The model is most likely to be used as a practical performance guide for client/server computing.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06a
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• pp.305-307
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• 2012

World Wide Web (WWW)의 지속적인 성장으로 인해 Web Service의 Response Time을 수집하는 방식에 관한 연구가 진행되고 있다. 현재 Client Response Time을 수집하는 방식은 sniffer[1] 를 이용한 Agent 방식을 사용하고 있다. 하지만, 기존의 방식은 클라이언트 PC에 설치되어 수집하게 되므로 Agent의 설치가 쉽지 않고, 관리 또한 어려운 문제점을 갖고 있다. 이러한 문제점을 개선하기 위하여, 본 논문에서는 Web Application Server (WAS)[2] 에서의 Dynamic HTML 변경을 통해 Client에 추가적인 Application을 설치하지 않고도 Client의 Response Time을 Collection하는 방식에 대하여 제안하였다. 이를 통해, 사용자 (End-User)에게 추가적인 응용 프로그램을 설치하지 않고도 Dynamic HTML 을 이용하여 Client Response Time을 수집함과 동시에 Server에 Feedback할 수 있다.

• The Transactions of the Korea Information Processing Society
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• v.2 no.5
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• pp.797-806
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• 1995

The Client-Server model is a computing technique that efficiently uses distributed resources via networks. But, generating an application using Client- Server model requires many different expertises to developers in comparison to that of using the centralized computing method. That is, and application developer must be familiar with network programming and GUI(Graphical User Interface) techniques in addition to conventional programming skills. Accordingly, the time and man power have been issued for building a Client-Server system. To alleviate these problem, the Client-Server applications development tools are needed To meet such a need, we developed a GUI based tool, called Hanuri/C, for generating Client-Server application programs. In comparison to existing Client-Server tools, Hanuri/C is reinforced Multimedia facilities, Hanuri/C is reinforced Multimedia facilities. Hanuri/C is considered as a front-end part of distributed system software. That is, Hanuri/C is a Client-Server tool similar to Forth Generation Language(4GL) supporting multimedia application on top of the Distributed Computing environment(DCE). In this paper, we present the design and implementation method of the middleware part of Hanuri/c.

• Journal of Digital Contents Society
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• v.10 no.4
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• pp.509-520
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• 2009

The advancement of network & application technology causes a major change for the use of IT(Information Technology) equipment, including computer and mobile system. In the process from beginning with main frame in the 1960s and 70's, through the server-client paradigm in the 1980s and toward the development of network computer since 90's, computer systems are now evolutioning from isolated physical system to complementary network based virtual system[1][2]. In network based computer system, application and data required for operation are stored at not client as local system, but at server[1]. User can use application & data on a server as if those are on a local client, and a client is now toward a developing thin and network friendly system. In this paper, we discuss possible ways for the efficient implementation of thin-client. For the use of remote application & data as if in local environment, we make use of X protocol. Unlike formal simple Client - Server paradigm, we design a Proxy for middle-tier server for the improvement of QoS and session persistence. X server, Xvfb(X virtual frame buffer) are implemented on thin client and Server, respectively and we applied XSMP(X Session Management Protocol) to our framework for session management. In the end, beyond simple transfer of server display, we suggest thin client framework for the transfter of remote server application over internet.

• Proceedings of the Korea Database Society Conference
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• 1994.09a
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• pp.105-129
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• 1994

The information system of corporations are facing a new environment expressed by miniaturization, decentralization and Open System. It is therefore of utmost importance for corporations to adapt flexibly th such new environment by providing for corresponding changes to their existing information systems. The objectives of this study are to identify this new environment faced by today′s information system and develop effective methods for data resource management under this new environment. In this study, it is assumed that the new environment faced by information systems can be specified as Distributed Computing Environment, and in order to achieve such system, presents Client/server architecture as its representative computing structure, This study defines Client/server architecture as a computing architecture which specialize the fuctionality of the client system and the server system in order to have an application distribute and perform cooperative processing at the best platform. Furthermore, from among the five structures utilized in Client/server architecture for distribution and cooperative processing of application between server and client this study presents two different data management methods under the Client/server environment; one is "Remote Data Management Method" which uses file server or database server and. the other is "Distributed Data Management Method" using distributed database management system. The result of this study leads to the conclusion that in the client/server environment although distributed application is assumed, the data could become centralized (in the case of file server or database server) or decentralized (in the case of distributed database system) and the data management method through a distributed database system where complete responsibility and powers with respect to control of data used by the user are given not only is it more adaptable to modern flexible corporate environment, but in terms of system operation, it presents a more efficient data management alternative compared to existing data management methods in terms of cutting costs.

• Journal of Korea Society of Industrial Information Systems
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• v.14 no.5
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• pp.19-32
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• 2009

In this paper, we design thin-client framework capable of application sharing & data access on the Internet, and apply related skills, such as X windows system, pseudo server, CODA file system, MPI(Message Passing Interface). We suggest a framework for the thin client to access data produced by working on a server optimally as well as to run server side application, even in the case of network down. Additionally, it needed to reflect all local computing changes to remote server when network is restored. To design thin client framework with these characteristics, in this paper, we apply distributed pseudo server and CODA file system to our framework, also utilize MPI for the purpose of more efficient computing & management. It allows for implementation of network independent computing environment of thin client, also provide scalable application service to numerous user through the elimination of bottleneck on caused by server overload. In this paper, we discuss the implementing method of thin client framework in detail.

• Journal of Digital Contents Society
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• v.8 no.2
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• pp.149-156
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• 2007

In this paper, I discuss the development techniques and implemented type of DAVIS, a standalone JAVA-based application, by which statistics application can be downloaded from a web server, stored and installed to a client. Also I discuss both the server-based application and the client-based application that analyze statistics data. Considering the strengths and weaknesses of types discussed previously, I propose an advanced learning system of statistics that can execute an application in a client by client request. And data used in this system are loaded from a database server or input into a client by users.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.9
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• pp.847-854
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• 2004

In this paper, It is studied to control and to monitor the remote system state using HTTP(Hyper Text Transfer Protocol) object communication. The remote control system is controlled by using a web browser or a application program. This system is organized by three different part depending on functionality-server part, client part, controller part. The java technology is used to composite the server part and the client part and C language is used for a controller. The server part is waiting for the request of client part and then the request is reached, the server part saves client data to the database and send a command set to the client part. The administrator can control the remote system just using a web browser. Remote part is worked by timer that is activated per 1 second. It gets the measurement data of the controller part, and then send the request to the server part and get a command set in the command repository of server part using the client ID. After interpreting the command set, the client part transfers the command set to the controller part. Controller part can be activated by the client part. If send command is transmitted by the client part, it sends sensor monitoring data to the client part and command set is transmitted then setting up the value of the controlled system.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10c
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• pp.292-294
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• 2002

정보시스템을 구축하기 위한 기술구조는 90년대 초까지의 호스트 중심의 기술구조에서 PC보급의 확대로 인해 Client/server 환경의 기술구조를 급격하게 발전시켜 왔다. 그러나 Client/server 구조는 사용이 간편하고 시스템 확장이 용이하다는 장점에도 불구하고 Client 관리에 큰 문제점이 나타났다. Client/server 관리의 문제점을 해결할 수 있는 대안으로 웹 환경의 인터넷/인트라넷 구조의 기술발전이 꾸준히 이루어졌으며, 현재는 Client/server와 같은 안정적인 OLTP(Online Transaction Processing)를 처리할 수 있는 수준까지 발전하였다. 본 논문에서 소개하는 운송정보시스템은 웹 환경의 인터넷/인트라넷을 이용한 시스템으로서, 중ㆍ소 운송업체와 자가 운송 사업자가 운송정보시스템을 구축하는데 있어서 초기 투자비용을 줄이고, 시스템의 유지 보수 및 확장이 용이한 ASP(Application Service Provider) 서비스를 효과적으로 제공한다. 이것은 차량의 위치정보를 통해 배차현황/출하차현황/도착현황/공차현황 등 물류 흐름을 파악하기 위한 운송 정보를 실시간으로 제공하고, 동종 유사 업체간의 표준화된 자료를 교환, 공유함으로써 효율적인 차량 관리가 가능하며, 물류비를 전감 할 수 있고, 작업의 효율성을 증대시켜 원활한 운송업무가 이루어지게 할 수 있을 것이다.