• Proceedings of the Korean Information Science Society Conference
• /
• 2000.10b
• /
• pp.496-498
• /
• 2000

기존의 웹 기반 3차원 가상환경 분야에 대한 연구는 시각적인 면에서 이전의 웹 컨텐츠에 비해 많은 향상이 있었다. 그러나 내부 객체들간의 다양한 상호작용이나 참여자를 대신하는 아바타(Avatar)의 행위(Behavior)표현에 대해서는 많은 한계를 가지고 있다. 본 논문에서는 아바타를 포함한 가상 객체간의 상호작용과 행위의 유형을 정의하며 이를 지원할 수 있는 가상환경서버를 설계하고 구현한다. 또한, 다중사용자의 참여로 인해 발생할 수 있는 서버의 성능저하를 줄이기 위한 방법론으로서 지역관리 및 메시지 필터링 기법을 제안한다. 구현된 시스템은 가상 쇼핑몰 등의 응용분야에 실제 적용이 가능하다.

• Journal of KIISE:Computer Systems and Theory
• /
• v.29 no.5
• /
• pp.265-273
• /
• 2002

With the explosive growth of WWW traffic, there is an increasing demand for the high performance Web servers to provide a stable Web service to users. The cluster-based Web server is a solution to core with the heavy access from users, easily scaling the server according to the loads. In the cluster-based Web sewer, a back-end node may not be able to serve some HTTP requests directly because it does not have the requested contents in its main memory. In this case, the back-end node has to retrieve the requested contents from its local disk or other back-end nodes in the cluster. To reduce service latency, we introduce a new prefetch scheme. The back-end nodes predict the next HTTP requests and prefetch the contents of predicted requests before the next requests arrive. We develop three prefetch algorithms bated on some useful information gathered from many clients'HTTP requests. Through trace-driven simulation, the service latency of the prefetch scheme is reduced by 10 ~ 25% as compared with no prefetch scheme. Among the proposed prefetch algorithms, Time and Access Probability-based Prefetch (TAP2) algorithm, which uses the access probability and the inter-reference time of Web object, shows the best performance.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.1 no.1
• /
• pp.3-12
• /
• 1997

In this study, in Tongyeong area the distribution of marine products that were produced and treated through fishing and cultivating industry and the trend of main fisheries were investigated for fisheries distribution system and fisheries official circles, and then a structural model of fisheries distribution system for direct transaction was suggested under internet environment, which is an important scheme offering a necessary information rapidly and practically to both producers and consumers. Database system was structured according to distributed process. An op-elative scheme were suggested for sewers of local area information center, complementing functions to exceed each server's ability.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2013.07a
• /
• pp.231-232
• /
• 2013

본 논문에서는 타 지역 상황이미지 공유를 위한 안드로이드 기반의 '거긴어때요?' 애플리케이션의 개발 내용에 대해서 기술한다. 이는 소켓통신을 이용한 서버/클라이언트 구조로 되어 있으며, 타 지역에 있는 사용자 간에 실시간으로 상황이미지을 공유하고 확인할 수 있는 시스템이다. 이 애플리케이션을 사용하는 A지역에 있는 사용자는 보고 싶은 B지역에 관한 요청 글을 올릴 수 있고, 알림을 받은 B지역에 있는 다른 사용자는 자기가 있는 B지역에 관한 이미지를 첨부하여 답변 글을 올릴 수 있다. 이는 네이버 지식인을 통해 사용자들이 각자 알고 있는 지식을 공유하듯이 본 애플리케이션을 이용해 타 지역을 직접 가지 않고서도 그곳의 상황이미지를 실시간으로 공유할 수 있도록 해 준다.

• Journal of KIISE:Computer Systems and Theory
• /
• v.33 no.10
• /
• pp.734-745
• /
• 2006

This paper presents a PC cluster-based distributed VOD server that minimizes the load of an interconnection network by adopting the VIA communication protocol and the interval cache algorithm. Video data is distributed to the disks of the distributed VOD server and each server node receives the data through the interconnection network and sends it to clients. The load of the interconnection network increases because of the large amount of video data transferred. This paper developed a distributed VOD file system, which is based on VIA, to minimize cost using interconnection network when accessing remote disks. VIA is a user-level communication protocol removing the overhead of TCP/IP. This papers also improved the performance of the interconnection network by expanding the maximum transfer size of VIA. In addition, the interval cache reduces traffic on the interconnection network by caching, in main memory, the video data transferred from disks of remote server nodes. Experiments using the distributed VOD server of this paper showed a maximum performance improvement of 21.3% compared with a distributed VOD server without VIA and the interval cache, when used with a four-node PC cluster.

• Proceedings of the Korean Society for Quality Management Conference
• /
• 2010.04a
• /
• pp.418-424
• /
• 2010

우리를 둘러싼 경영환경은 시간, 공간, 무용지식등을 심층기반으로 하여 움직이고 였다. 이런 경영 환경속에서 하이테크와 하이터치 요인을 통해 고객에게 만족을 주지 못하면 개인이나 조직은 고객의 뇌리 속에서 사라지게 된다. 이런 배경으로 인해, 지역축제 역시 일반 축제와 차별적인 방향으로 개발하여 고객에게 가치를 제공해야 하는 전략을 강구할 필요가 있다. 본 연구에서는 지역 문화 콘텐츠를 암리고 지역 경제적 수익을 위해서 마련한 지역축제를 돌아 보는데였다. 또한 연구모형을 개발하고 지역축제의 서비스 품질 만족요인이 축제의 만족도와 재방문에 마치는 인과분석을 실시하는데 있다. 본 연구 분석결과, 서버스 품질 요인 중 행사진행 벚 수용태세 요인과 쇼핑 및 음식요인이 고객만족도에 유의한 영향을 마치는 것으로 나타났으며, 고객만족도는 향후 지역축제 참여의도에 유의한 영향을 미치는 것으로 나타났다.

• The Journal of the Korea Contents Association
• /
• v.6 no.1
• /
• pp.72-79
• /
• 2006

Recently, a MMORPG(Massively Multi-play Online Role Playing Game) has built distribute server by Seamless world. This paper proposes an efficient collision detection method. DLS is used to dynamically adjust spatial subdivisions in each the boundary regions of distribute server We use an index table to effectively utilize the relationships between in the nodes and can perform the collision detection efficiently by reconstructing nodes of the tree. Also, we maintain the information for the boundary region to efficiently detect the collections and adjust the boundary regions between distributed servers by using DLS. As the DLS uses pointers, the information for each server is not needed and the boundary regions between the distributed servers are efficiently searched. Using node index points, the construction table can be made to find between ray and neighborhood node, In addition, processes for Network traffic reduce because a copy of the boundary regions is not needed when a object moves with realtime.

• The Transactions of the Korea Information Processing Society
• /
• v.7 no.2
• /
• pp.488-496
• /
• 2000

this paper describes the design and implementation of node scheduling for MX Server that is CC-NUMA System COMSIX, the operating system of MX Server, is designed to suit for CC-NUMA Architecture. MX Server consists of up to 8 nodes, and each node is connected by SCI ring. This node scheduling scheme considers data locality for performance improvement of Oracle8i DBMS on the CC-NUMA architecture. For DBMS such as Oracle8i, a multi-threaded process may be run to tie on particular disk. We have developed a CG binding function that the multi-threaded process bound the node. Currently, We don't have an available CC-NUMA Platform. Instead of MX Server, we developed the Node scheduling scheme for multi-threaded process to suit server platform on the PC test-bed and tested completely.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.2
• /
• pp.493-500
• /
• 2011

Recently, there has been an increase in the number of disaster victims locally due to climate change and a variety of frequently occurring natural disasters. The damage caused by abrupt weather change in local area by typical weather forecasting techniques is very limited and difficult. Recently local area weather monitoring system using wireless sensor network technology has been very actively studied. Thus an IEEE 802.15.4-based weather field server to measure and monitor the local weather changes was designed and developed in this study. The proposed weather field server utilizes a wireless sensor node and weather sensors to collect weather information such as temperature, humidity, illumination, dew point, barometric pressure, and water level. The integrated weather sensor board was designed to respond quickly to weather changes, and provide feedback to the server PC. Each weather information is analyzed in the server PC to establish a program to monitor and analyze the local area or the area of abrupt climate change in order to provide warning signals in case of disaster events in local.

• The KIPS Transactions:PartC
• /
• v.9C no.4
• /
• pp.605-614
• /
• 2002

Amount of the web traffic web server handles are explosively increasing, which requires that the performance of the web server should be improved for the various web services. Although the analysis for the HTTP traffic with the proper tuning for the web server is essential, the research relevant to the subject are insignificant. In particular, although most of applications are implemented over HTTP 1.1 protocol, the researches mostly deal with the performance evaluation of the HTTP 1.0 protocol. Consequently, the modeling approach and the performance evaluation over HTTP 1.1 protocol have not been well formed. Therefore, basing on the HTTP 1.1 protocol supporting persistent connection, we present an analytical end-to-end tandem queueing model for web server to consider the specific hardware configuration inside web server beginning at accepting the user request until completing the service. we compare various performances between HTTP 1.0 and HTTP 1.1 under the overloading condition, and then analyze the characteristics of the HTTP traffic that include file size requested to web server, the OFF time between file transfers, the frequency of requests, and the temporal locality of requests. Presented model is verified through the comparing the server throughput according to varying requests rate with the real web server. Thereafter, we analyze the performance evaluation of the web server, according to the interrelation between TCP Listen queue size, the number of HTTP threads and the size of the network buffers.