• Journal of Korea Spatial Information System Society
• /
• v.11 no.1
• /
• pp.9-16
• /
• 2009

In ubiquitous spatial computing environments, GeoSensor generates sensor data streams including spatial information as well as various conventional sensor data from RFID, WSN, Web CAM, Digital Camera, CCTV, and Telematics units. This GeoSensor enables the revitalization of various ubiquitous USN technologies and services on geographic information. In order to service the u-GIS applications based on GeoSensors, it is indispensable to efficiently process sensor data streams from GeoSensors of a wide area. In this paper, we propose a GeoSensor data stream processing system for u-GIS computing over real-time stream data from GeoSensors with geographic information. The proposed system provides efficient gathering, storing, and continuous query processing of GeoSensor data stream, and also makes it possible to develop diverse u-GIS applications meet each user requirements effectively.

• The KIPS Transactions:PartB
• /
• v.12B no.6 s.102
• /
• pp.661-670
• /
• 2005

According as services that offer multimedia streams are activated on the Internet, users who use these services we increased extremely. As a result of this, the increase of network traffic was occurred. Also it caused the problems such as the discontinuous playback in case of the s#ream playback and the asynchronization between a video and an audio. To solve these problems, it needs a method that guarantee the stable playback of media streams and a method of media transfer that can interact between a service user and media. Existing related researches has achieved the synchronization through various methods, but did not shown the results of satisfaction in the aspect of interaction. In this paper, we inserted the interactive objects in each media file, designed functions that these objects can use each other's information, and solved the interaction and the synchronization between a video and an audio. Also, we solved the discontinuous playback of a stream by the insufficiency of network bandwidth through using variable buffers.

• The KIPS Transactions:PartD
• /
• v.9D no.5
• /
• pp.945-954
• /
• 2002

Clickstream is the information which demonstrate users' path through web sites. Analysis of clickstream shows how web sites are navigated and used by users. Clickstream of online web sites contains effective information of web marketing and to offers usefully personalized services to users, and helps us understand how users find web sites, what products they see, and what products they purchase. In this paper, we present an extended web log system that add to module of collection of clickstream to understand users' behavior patterns In web sites. This system offers the users clickstream information to database which can then analyze it with ease. Using ADO technology in store of database constructs extended web log server system. The process of making clickstreaming into database can facilitate analysis of various user patterns and generates aggregate profiles to offer personalized web service. In particular, our results indicate that by using the users' clickstream. We can achieve effective personalization of web sites.

• The KIPS Transactions:PartC
• /
• v.8C no.6
• /
• pp.765-774
• /
• 2001

In this paper, we proposed the striping policy for the storage nodes in the Linux-based parallel media stream server. We newly developed a storage clustering architecture, and named it as a system RAID architecture. In this system, many storage cluster nodes are grouped to operate as a single server. This system uses unique striping policy to distribute multimedia files into the parallel storage nodes. If a service request occurs, each storage cluster node transmits striped files concurrently to the clients. This scheme can provide the fair distribution of the preprocessing load in all storage cluster nodes. The feature of this system is a relative striping policy based on the file types, service types, and the number of storage nodes to provide the best service.

• The Transactions of the Korea Information Processing Society
• /
• v.7 no.11S
• /
• pp.3651-3667
• /
• 2000

Recently, in the distributed multimedia environments based on internet, as radical growing technologies, the most of researchers focus on both streaming technology and distributed object thchnology, Specially, the studies which are tried to integrate the streaming services on the distributed object technology have been progressing. These technologies are applied to various stream service mamgements and protocols. However, the stream service management mexlels which are being proposed by the existing researches are insufficient for suporting the QoS of stream services. Besides, the existing models have the problems that cannot support the extensibility and the reusability, when the QoS-reiatedfunctions are being developed as a sub-module which is suited on the specific-purpose application services. For solving these problems, in this paper. we suggested a QoS Integrated platform which can extend and reuse using the distributed object technologies, and guarantee the QoS of the stream services. A structure of platform we suggested consists of three components such as User Control Module(UCM), QoS Management Module(QoSM) and Stream Object. Stream Object has Send/Receive operations for transmitting the RTP packets over TCP/IP. User Control ModuleI(UCM) controls Stream Objects via the COREA service objects. QoS Management Modulel(QoSM) has the functions which maintain the QoS of stream service between the UCMs in client and server. As QoS control methexlologies, procedures of resource monitoring, negotiation, and resource adaptation are executed via the interactions among these comiXments mentioned above. For constmcting this QoS integrated platform, we first implemented the modules mentioned above independently, and then, used IDL for defining interfaces among these mexlules so that can support platform independence, interoperability and portability base on COREA. This platform is constructed using OrbixWeb 3.1c following CORBA specification on Solaris 2.5/2.7, Java language, Java, Java Media Framework API 2.0, Mini-SQL1.0.16 and multimedia equipments. As results for verifying this platform functionally, we showed executing results of each module we mentioned above, and a numerical data obtained from QoS control procedures on client and server's GUI, while stream service is executing on our platform.

• Journal of KIISE:Information Networking
• /
• v.30 no.2
• /
• pp.260-269
• /
• 2003

The traditional distributed object middleware platform is not suitable for the transmission of stream data, because RPC(Remote Procedure Call)-based message transmission have a great overhead. Therefore, the OMG(Object Management Group) proposes the AV(Audio and Video) stream reference model for streaming on the distributed object middleware platform. But, this reference model has not a detail of implementation. Particularly it also has not congestion control scheme for improvement of network efficiency on the real network environment. It is a very important and difficult technical issue to provide the stream transmission platform with advanced congestion control scheme. In this paper, we propose an architecture of a distributed stream transport platform and deal with the design and implementation concept of our proposed platform. Also, we present a mechanism to improve streaming utilization by SRTP(Smart RTP). SRTP is our proposed TCP-Friendly scheme.

• Journal of Korea Spatial Information System Society
• /
• v.8 no.1 s.16
• /
• pp.1-16
• /
• 2006

Recently, human based computing environment for supporting users to concentrate only user task without sensing other changes from users is being progressively researched and developed. But middleware deletes steream data processed for reducing process load of massive information from RFID sensor in this computing. So, this kind of middleware have problems when user demands probability or statistics needed for data warehousing or data mining and when user demands very important stream data repeatedly but already discarded in the middleware every former time. In this paper, we designs Sensor Middleware Architecture on Multi Level Spatial DBMS with Snapshot and manage repeatedly required stream datas to solve reusing problems of historical stream data in current middleware. This system uses disk databse that manages historical stream datas filtered in middleware for requiring services using historical stream information as data mining or data warehousing from user, and uses memory database that mamages highly reuseable data as a snapshot when stream data storaged in disk database has high reuse frequency from user. For the more, this system processes memory database management policy in a cycle to maintain high reusement and rapid service for users. Our paper system solves problems of repeated requirement of stream datas, or a policy decision service using historical stream data of current middleware. Also offers variant and rapid data services maintaining high data reusement of main memory snapshot datas.

• Proceedings of the Korean Information Science Society Conference
• /
• 2000.04a
• /
• pp.382-384
• /
• 2000

WWW의 성장으로 인터넷은 과부하 상태에 이르렀으며, 현재 인터넷 상에는 오디오나 비디오 같은 연속미디어 데이터가 급격히 증가하는 추세에 있다. 본 논문은 인터넷상의 연속미디어 데이터의 효율적인 서비스를 위한 프락시 캐슁 기법을 제안한다. 연속미디어 스트림의 앞부분부터 점진적으로 캐슁하고, 스트림의 캐슁 길이를 유동적으로 변화시켜서 인기도에 따른 사용공간의 차별화를 수행한다. 그리하여 캐쉬의 제한된 저장공간을 보다 효율적으로 사용하고, 클라이언트의 서비스 지연시간을 최소화 시킬 수 있다. 그리고, 실험을 통하여 다른 알고리즘과의 성능을 비교 측정한다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2002.10d
• /
• pp.151-153
• /
• 2002

최근 이동 통신 서비스의 발전에 따른 멀티미디어 서비스가 본격적으로 상용화되고 있다. 그러나 여전히 이동 단말기에서의 멀티미디어 스트링의 재생과 편집은 이동 통신의 낮은 대역폭, 고용량의 멀티미디어 데이터, 이동 단말기의 처리 능력 등의 여러 한계점을 가지고 있다. 이에 본 논문에서는 멀티미디어 스트림 엔진인 Transcore와 멀티미디어 데이터 편집 둘인 VIP를 기반으로 하여 다수의 멀티미디어 스트림을 이동 단말기에서 편집 및 재생하기 위한 프리젠테이션 편집기를 연구하고자 한다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2015.07a
• /
• pp.337-338
• /
• 2015

최근 들어 기존의 MPEG-2 시스템에서 벗어난 차세대 방송 서비스 및 시스템 기술에 대한 관심이 고조되고 있다. 즉, 부호화된 콘텐츠를 전송하기 위해서 현재 사용되고 있는 MPEG-2 스트림 대신, 세그먼트 기반의 IP를 활용하는 방향으로 변모하고 있다. 더욱이, 차세대 방송 표준화를 추진 중에 있는 ATSC 3.0 에서는 MPEG-2 스트림을 제외하고 세그먼트 기반의 IP 만 고려하고 있다. 본 논문에서는 이러한 기술 기반의 차세대 방송 서비스 및 시스템 개발을 위해서 필요한 콘텐츠 반복 재생 방법을 제안한다. 제안된 방법은 기존 디지털 방송에서 사용하고 있는 MPEG-2 스트림의 반복 재생과 동일하게, 제한된 용량의 콘텐츠를 반복 재생하여도 연속적으로 재생되는 것처럼 보이도록 하여 실제 방송 환경과 동일한 테스트 환경을 제공한다. 향후, 세그먼트 기반의 차세대 방송 서비스의 도입 단계에서 제안된 내용이 많이 활용될 것으로 기대한다.