• 한국방송∙미디어공학회:학술대회논문집
• /
• 한국방송공학회 2001년도 디지털 방송기술 워크샵
• /
• pp.335-354
• /
• 2001

.Next Generation Multimedia Streaming Technology Massive Scale Support $\rightarrow$ Clustered Solution Adaptive to Heterogeneous Network daptive to Heterogeneous Terminal Capability Presentation Technique .SMART Server Architecture .HERMES File System .Clustered Solution . High Speed Storage Interconnect .' Content Partitioning . Load Management . Support for Heterogeniety . Adaptive End to End Streaming Transport: Unicast vs. Multicast '. Scalable Encoding

• 한국CDE학회논문집
• /
• 제13권2호
• /
• pp.89-97
• /
• 2008

Today's manufacturing environment is becoming a distributed manufacturing process in which a unique and specialized technological background is required in specific domains rather than having a single company execute all the manufacturing processes. This phenomenon is especially true in the automotive industry, where the sharing of product data between companies is rampant; however, this kind of interoperability causes many problems. When each company has its own method of managing product data, the sharing of product data in a distributed environment is a major problem. A data translator module or a data mapping module had to be developed for the exchange of data in heterogeneous systems of product data management (PDM); moreover, this type of module must be continually changed and improved due to the fact that PDM systems change for many reasons. In addition, the growth in corporate partnerships deepens the burden of developing and maintaining this module and creates further data exchange problems due to the increasing complexity of the system. This paper introduces a way of exchanging product data among heterogeneous PDM systems through the use of OpenPDM, which is a kind of virtual data warehouse. The implementation of a PDM integrating system is also discussed with respect to the requirement for a logical integration of product data which are physically distributed.

• 한국전자거래학회지
• /
• 제3권1호
• /
• pp.23-41
• /
• 1998

In a centralized database system, all system components reside at a single platform. In recent years there has been a rapid trend toward the integration of information systems over multiple sites that are interconnected via a communication network, and users' needs are changed to integration of multiple information sites. Multi database System is one of solutions for integrating distributed heterogeneous databases. However the problems in multi database system are restriction in distributed environment support, limitation in integrating heterogeneous media type data, static integration, and data-only of integration. In order to solve these problems, we propose a hybrid database integration model, HyDIM. HyDIM is used for the integrating legacy multimedia data, adopting CORBA, MDS, and mediator. We demonstrate a prototype system far PDM application domain.

• 전자공학회논문지B
• /
• 제32B권12호
• /
• pp.1687-1696
• /
• 1995

An integrated fault diagnosis system for heterogeneous manufacturing environments is developed. This system has a contrast with existing diagnosis systems in the respect that they are mostly for diagnosing faults on individual machines. In addition to the usual (e.g., audio, electrical) diagnostic signals, the characteristics of products from the machines are considered as the unifying diagnostic parameters among heterogeneous machines in the diagnosis. The system is composed of a knowledge representation scheme and a diagnostic query processing mechanism. Its knowledge representation scheme allows the diagnostic knowledges from heterogeneous unit diagnostic systems to be uniformly expressed in terms of the causal relations among relevant data items. It is flexible in the sense that causes for one relation can be effects for another may be reflected on our knowledge representation scheme. The diagnosis mechanism is based on a probabilistic inferencing method. This probablistic diagnosis mechanism provides more general diagnosis than existing ones in that it accommodates multiple causes and takes complication among causes into account. These scheme and mechanism are applied to a typical example to demonstrate how our system works.

• 한국산학기술학회논문지
• /
• 제6권6호
• /
• pp.506-512
• /
• 2005

부하재분배 방법은 컴퓨터시스템에서 중요한 요소이다. 수신자 개시 부하재분배 알고리즘에서는 전체 시스템이 저부하일 때 수신자(저부하 프로세서)가 부하를 이전 받기 위해 송신자(과부하 프로세서)를 발견할 때까지 불필요한 이전 요청 메시지를 계속 보내게 된다. 따라서 이 같은 상황에서는 과부하 상태인 송신자 프로세서로부터 승인 메시지를 받기까지 불필요한 프로세서간 통신으로 인하여 프로세서의 이용률이 저하되고, 타스크 처리율이 낮아지는 문제점이 발생한다. 본 논문에서는 유전알고리즘을 기반으로 하여 자기조절 능력을 포함토록 한 이질형 분산 시스템에서의 동적 부하재분배 접근 방법을 제안한다. 이 기법에서는 불필요한 요청 메시지를 줄이기 위해 요청 메시지가 전송될 프로세서들이 제안된 유전 알고리즘에 의해 결정된다.

• 한국정보처리학회논문지
• /
• 제6권11호
• /
• pp.2875-2888
• /
• 1999

In this paper we present compiler-based active rule system to efficiently maintain spatial integrity constraints in a heterogeneous, distributed environment. Specially, the prototype active rule system presented has been developed as a component of a whole middleware system called SDBC(Spatile DataBase Connectivity). Due to this reason, our active rule system is provided for heterogeneous ODBMSs in a distributed environment and used to define spatial integrity constraints using the active rules in E-C-A(Event-Condition-Action) type. Using this active rule system, an application programmer can free himself from a heavier burden on the integrity maintenance of application objects. In the compiler-based approach, active rules applicable to events raised by a database program are directly inserted into the program in a function type by the preprocessor, and then they are compiled with the application program source codes. One advantage of this approach is that there is no run-time overhead accompanied by monitoring all the database transitions when preprocessed program is executed. This active rule system also provides facilities to manage changed rules and dynamically interpret those rules at run-tuime.

• 전자공학회논문지CI
• /
• 제46권3호
• /
• pp.86-95
• /
• 2009

이기종 컴퓨팅 환경에서 방향성 비순환 그래프(directed acyclic graph DAG)의 효율적인 스케줄링은 시스템의 성능을 높게 만드는데 매우 중요한 역할을 한다. 이기종의 컴퓨팅 환경에서 DAG로 표현되는 프로그램의 최적 스케줄링 방법을 찾는 것은 잘 알려진 '정해진 시간 내에 해결하기 어려운 문제(NP-complete)' 이다. 본 논문은 분산 이기종 컴퓨팅 시스템에서 병렬로 실행 가능한 프로그램을 위한 새로운 리스트 스케줄링 알고리즘인 HRPS(Heterogeneous Rank-Path Scheduling)를 제안하였다. HRPS의 가장 궁극적인 목적은 프로그램의 실행시간을 최소화하는 것이다. 알고리즘의 성능을 위해 DAG 입력 그래프를 이용하여 기존에 제안되어진 CPOP, HCPT, FLB 알고리즘과 스케줄의 길이를 비교한 결과 성능 향상의 결과를 얻을 수 있었다.

• 한국컴퓨터정보학회논문지
• /
• 제11권1호
• /
• pp.1-10
• /
• 2006

부하재분배 방법은 컴퓨터시스템에서 중요한 요소이다. 수신자 개시 부하재분배 알고리즘에서는 전체시스템이 저부하일 때 수신자(저부하 프로세서)가 부하를 이전받기 위해 송신자(과부하 프로세서)를 발견할 때까지 불필요한 이전 요청 메시지를 계속 보내게 된다. 따라서 이같은 상황에서는 과부하 상태인 송신자 프로세서로부터 승인 메시지를 받기까지 불필요한 프로세서간 통신으로 인하여 프로세서의 이용률이 저하되고, 타스크 처리율이 낮아지는 문제점이 발생한다. 본 논문에서는 이질형 분산 시스템에서의 동적 부하재분배를 위해 유전 알고리즘을 기반으로 하는 접근 방법을 제안한다. 이 기법에서는 불필요한 요청메시지를 줄이기 위해 요청 메시지가 전송될 프로세서들이 제안된 유전 알고리즘에 의해 결정된다.

• International Journal of Reliability and Applications
• /
• 제1권2호
• /
• pp.105-113
• /
• 2000

This paper discusses some problems of the TMN-based architecture of integrated network management systems and presents a CORBA-based architecture of distributed network management system with reliability, which maintains location transparency of distributed managed objects and provides an interoperability among heterogeneous networks and systems. In this paper, the proposed distributed management system model has been applied to the TMN based management systems and then considered for qualitative evaluation of system performance. Two different types of implementation models have been proposed: one is a system using a CORBA gateway and the other is a pure CORBA system, which maps all managed objects into CORBA objects. The characteristics of two system model have been compared in the respect of system implementation

• 한국전자거래학회지
• /
• 제2권2호
• /
• pp.155-169
• /
• 1997

The CALS integrated database is a key information technology in which CALS implements an information sharing system to enable digital data transfers for technical and non-technical information in distributed and heterogeneous environments. Such heterogeneously distributed CALS information needs to be systematically incorporated so that it can provide a global data view for CALS users. In this paper, we investigated the technologies of CALS integrated database, and proposed a system prototype to implement an integrated data environment (IDE) utilizing distributed object environments CORBA (Common Object Request Broker Architecture).