• 한국멀티미디어학회논문지
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• 제15권12호
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• pp.1464-1474
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• 2012

In this paper, we propose a QoS (Quality of Service)-aware and cooperative resource reservation scheme using cross-layer link adaptation for wireless high definition video transmission through UWB (Ultra Wide Band) network with D-MAC (Distributed Medium Access Control). A wireless high definition video transmission system usually requires stable high throughput even without line-of-sight, e.g., a destination device in another room separated by a wall. Since the WiMedia D-MAC supporting DRP (Distributed Reservation Protocol) scheme causes lots of DRP resource reservation conflicts due to failure of beacon detection in wireless channel environment, overall performances of the WiMedia D-MAC can be deteriorated. And the current WiMedia MAC standard has not considered QoS provisioning even though QoS parameters such as a range of service rates are provided to each traffic stream. Therefore, we propose Relay DRP protocol with QoS-based relay node selection criterion, which makes a relay path to avoid DRP resource reservation conflicts and guarantee QoS more stably through cross-layer link adaptation of cooperative relay transmission scheme and is compliant with the current WiMedia D-MAC protocol. Simulation results demonstrate performance improvements of the proposed method for throughput and QoS provisioning.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.723-726
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• 2000

In this paper, we present an abstract object-oriented plat-form model .suitable for the real-time distributed telecommunication system. The proposed platform is constructed upon the extended version of the real-time, distributed operating system, SROS(Scalable Real-time Operating System), that is developed at ETRI and successfully operated in the ATM switching system for several years. The object-oriented software development and maintenance methodology will resolve the current software crisis in the area of telecommunication and switching systems due to the everlasting maintenance about the huge amount of the existing software and the ever increasing needs for the better and new communication services. In general, an object-oriented software platform realizes the object-oriented methodology and possesses many good aspects like high productivity, better reusability, easy maintenance, et at. The platform is also designed to present the distributed multimedia service in addition to real-time event delivery. Recently, we have been implementing a couple of prototype bated on the proposed platform. Reflecting the evaluation results from these prototypes, the final platform specification will be determined.

• 기술사
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• 제30권2호
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• pp.79-86
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• 1997

As network has high speed and wide communication capability, users demand diverse and new software to satisfy their needs. To meet users needs, the softwares for multimedia or groupware or distributed virtual environments can communicate the widely distributed information fast and accurately. Even though the technology for this is under development, it is deficient to support the reliable computer communication. Distributed Object System aims, as the new paradigm of distributed system software development to overcome this problem, to obtain in distributed environment the easiness of development and management, expandability, reusability which object oriented technologies support by solving the complexity of communication processing through the object oriented methods. This paper aims to introduce distributed object system, its technological properties and the current status and trend of technology development related to its standardization. Additionally, with explaining the Replicated Shared Object System(RSOS) which is developed in our country as one of the distributed object systems, its future prospects and technical issues are discussed.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 1997년도 Proceedings International Workshop on New Video Media Technology
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• pp.55-60
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• 1997

Innovation on digital compression technology, high speed networking technology, digital broadcasting technology and distributed processing technology provides new interactive multimedia service that integrates telecommunication, broadcasting, and computer application. To meet the new trends, we focus our research direction to integrate the telecommunication services and the broadcasting services. For this purpose, we designed and implemented an interactive multimedia service platform based on the DAVIC specification. Our research results in the development of integrated interactive services and its experience will be feedback to the field trial service that will be launched from next year. In this paper, we will describe the overall architecture and system implementation results of the interactive multimedia service platform.

• 전자공학회논문지C
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• 제35C권3호
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• pp.59-68
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• 1998

This paper propose a hardware architecure of multimediasysgem for integrated processing of the multimedia data such as audio and video, and describes on the design and implementation of multimedia integrated processing Unit. The unit comprises most commonly needed multimedia processing function for computer-based video conference: audio-visual datacapture, playback, compression, decompression as well as interleaving/disinterleaving of compressed audio-visual data. The proposed architecture minimizes the CPU overhead that might be caused by multimedia data processing and assures the fluent data flow among system components. Also, this unit is tested and analyzed under the computer-based video conference to confirm the multimedia unit of proposed architecture using communication protocol and application software through Ethernet and FDDI (Fiber Distributed Data Interface) networks.

• 한국컴퓨터정보학회논문지
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• 제20권8호
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• pp.77-83
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• 2015

The storage and retrieval of multimedia data is becoming increasingly important in many application areas including record management, video(CCTV) management and Internet of Things (IoT). In these applications, the files containing multimedia that need to be stored and managed is tremendous and constantly scaling. In this paper, we propose a technique to retrieve a very large number of files, in multimedia format, using the Hadoop Framework. Our strategy is based on the management of metadata that describes the characteristic of files that are stored in Hadoop Distributed File System (HDFS). The metadata schema is represented in Hbase and looked up using SQL On Hadoop (Hive, Tajo). Both the Hbase, Hive and Tajo are part of the Hadoop Ecosystem. Preliminary experiment on multimedia data files stored in HDFS shows the viability of the proposed strategy.

• 한국통신학회논문지
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• 제22권10호
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• pp.2219-2235
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• 1997

멀티미디어 통신에서 호에 참여하는 단말(endpoint)과 교환기는 설정되는 대역폭과 베어러 수용 능력에 따라 동일 호에 다양한 특성의 연결을 설정할 수 있어야 한다. 또한 다자간 통신에서 호 참여자가 증가하는 경우, 호 설정에 소요되는 셀정지연이 크게 증대되어서는 안된다. 본 논문에서는 다양한 연결 형태의 다자간 멀티미디어 통신을 지원하기 위한 신호 프로토콜로서 DMMSP(distributed multiparty multiconnection signaling protocol)를 제안한다. DMMSP에서는 기존 프로토콜의 신호능력의 한계를 극복하고 다양한 연결 형태를 지원하기 위한 신호 능력을 제공하여 각 단말과 교환기는 베어러 수용 능력에 따라 독립된 연결을 설정한다. 또한 호 처리 (call processing)절차를 분리하여 분산 수행함으로써 설정지연을 줄이고 설정 절차를 최소화한다. 기존의 신호 프로토콜과 DMMSP의 호 제어 절차를 비교 정리하고 각 제어 방법에 따른 신호 절차를 제시하였다. 선호 절차는 다자간 멀티미디어 회의 호를 예로 들어 기존 프로토콜과 DMMSP를 이용한 절차로 구분하였고, 각각의 절차에 대해 정량적으로 비교 분석하였다.

• 한국정보시스템학회지:정보시스템연구
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• 제8권2호
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• pp.5-27
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• 1999

The recent development of information technology in general and consolidation of communications and multimedia technology in particular have brought enormous changes in education and training methods in many business organizations. Numerous studies in the education engineering field report that teaching using multimedia technologies will more enhance the education/training performance than the traditional instructor-teaching method. However, in the management information systems field, few studies are found which directly investigated effects of multimedia technologies on education and training. None of multimedia-related studies can be found in the top-ranked MIS journals published in Korea for the last five years, and only a few stuides are found even worldwide. The major steps of the current research are as follows. First, in order to identify important factors constituting the effectiveness of multimedia systems, previous research related to the effectiveness of multimedia systems was reviewed and analyzed. Second, individual items which can be considered as candidates to represent the effectiveness of multimedia systems were derived from this previous research review, and a survey questionnaire was developed using those derived items. Based on the developed survey questionnaire, a pretest was administered at several domestic business firms with experiences of multimedia systems. Third, survey questionnaires were distributed to and collected from the 517 employees which experienced using multimedia systems.

• 한국정보처리학회논문지
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• 제4권5호
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• pp.1153-1161
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• 1997

본 논문에서는 우리는 CBM기반의 상호참여형 멀티미디어 원격 진료시스템을 제안 하고 있는데, 본 시스템은 데이타베이스와 면대면 효과와 함께 특수진료 및 상호참여 진료 를 지원하고 있다. 본 시스템은 두레(Doorae:Distributed Obdected Oriented Multimedia Application Crafting Enviroment for Coollaboration)프레임웍의 SDK(Sofrware Development Kit)에 의해서 된 응용 시스템이고, 윈도우 95와 윈도우상 NT상에서 개발 되었다.본 시스템의 시나리오는 병원내(LAN환경)로 한정 지었으나, 두레상에서의 다양한 네트워크(MAN,PSTM,WAN)의 많은 응용 개발이 가능하다. 본 시스템은 비디오/오디오, 다중세션, 다중 참여자, 응용공유, 아이콘 및 툴박스 그리고 화이트보드에 의해서 부드러운 상호작용을 하고 있다. 또한 본 시스템은 시간과 공간의 제약이 없는 실시간 및 비실시간을 지원하고 있다.

• 정보처리학회논문지A
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• 제9A권1호
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• pp.9-18
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• 2002

본 논문에서는 분산 실시간 멀티미디어 데이터베이스 시스템에서 경성 실시간 태스크들과 멀티미디어 태스크들을 효율적으로 통합할 수 있는 신축적인 스케쥴링 기법이 제시된다. 경성 실시간 태스크가 최악의 경우에 대한 실행 시간을 기반으로 하는 반면 멀티미디어 태스크는 평균 실행 시간을 기반으로 한다. 동일한 시스템에 존재하는 두 가지 태스크들에 대하여 CPU 대역폭을 분할 조정하는 서버 기법이 기술된다. 제시된 기법에서는 한부류의 태스크들의 수와 도착 비율이 변동되는 과부하 문제를 해결하기 위하여 부류별로 CPU 대역폭의 비율이 조정될 수 있다. 경성 실시간 태스크가 서버의 주기내에서 실행될 수 있는 시간이 제한되는 반면 멀티미디어 태스크에 설정된 대역폭은 동적으로 변할 수 있다. 제시된 기법은 경성 실시간 태스크들의 실시간성을 모두 보장하는 한편 멀티미디어 태스크들의 평균 지연시간을 최소화할 수 있다. 스케쥴링 기법의 성능은 시뮬레이션을 통하여 다른 스케쥴링 기법과 비교 분석한다.