• 제어로봇시스템학회논문지
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• 제13권10호
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• pp.933-939
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• 2007

Safety critical systems such as x-by-wire systems require in-vehicle network systems that can interconnect various sensors, actuators, and controllers. These networks need to have high data rate, deterministic operation, and fault tolerance. Recently, FlexRay protocol that is a time-triggered protocol has been introduced, and many automotive companies have been focusing on this protocol. This paper presents a design method of FlexRay network system and implementation of FlexRay-based motor control system.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 춘계종합학술대회
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• pp.725-728
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• 2003

무선 통신망의 경우 기존의 유선망에 비해, 설치, 이동성 등이 우수하여 많은 기술적인 발전을 보이고 있다. 본 논문에서는 인터넷망에서 사용될 수 있는 가설 사설망 환경에서의 신뢰성을 가질 수 있는 네트워크의 구조에 대해 설명하였다. 또한, 안전한 네트워크의 가설사설망의 실현에 대해 제안하였다.

• 한국통신학회논문지
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• 제22권2호
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• pp.259-267
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• 1997

The advent of B-ISDN using ATM(asynchronous transfer mode) made possible a variety of new multimedia services, however it also created a problem of congestion control due to bursty nature of various traffic sources. To tackle this problem, UPC/NPC(user parameter control/network parameter control) have been actively studied and DRLB(dynamic rate leaky bucket) algorithm, in which the token generation rate is changed according to states of data source andbuffer occupancy, is a good example of the UPC/NPC. However, the DRLB algorithm has drawbacks of low efficiency and difficult real-time implementation for bursty traffic sources because the determination of token generation rate in the algorithm is based on the present state of network. In this paper, we propose a more plastic and effective congestion control algorithm by combining the DRLB algorithm and neural network based prediction to remedy the drawbacks of the DRLB algorithm, and verify the efficacy of the proposed method by computer simulations.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2003년도 춘계학술발표논문집 (중)
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• pp.1071-1074
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• 2003

Now internet is very popular. Many company services various contents in Web. One of the best way for internet community is network game service for internet member. There are some company to service high quality network game for gathering members. Those company make success for getting fee from their member. Global on-line game market is small but stability growing. Thus Microsoft invest on line game. On this paper, one of a java network turn game system called by "Hoola" is designed and implemented. This Application consist of Client/Server and Database module and multi-tier Architecture, because of easily translation to PDA or mobile phone.

• 한국정보처리학회논문지
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• 제7권8호
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• pp.2452-2462
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• 2000

네트워크 게임은 네트워크상의 분산된 사용자들이 경쟁과 협력을 통하여 결과를 만들어 가는 것으로서 공동작업의 한 형태로 볼 수 있다. 본 논문에서는 그룹 통신 플랫폼을 사용하여 네트워크 게임을 수행하기 위한 요구사항을 정리하고 이러한 요구사항을 수용하는 데드 리커닝의 설계와 구현에 관하여 기술한다. 이러한 노력은 게임 개발의 생산성을 높여주고, 사용자간 대화기능 등을 활용하여 게임의 질을 높일 수 있다. 또한 다양한 망과 단말의 능력 또한 게임 제공자, 게임 그룹 생성자의 의견에 따라서 유연한 형태로 다양한 결과를 제공할 수 있다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.95-98
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• 2003

To provide high-quality media streaming service over the best-effort Internet, an efficient streaming system with a network-adaptive transport is essential. By adopting FEC-based adaptive transport and by matching it to the priority of media packets, in this paper, an enhanced MPEG-4 streaming system is implemented. The implemented adaptive transport can complement the existing MPEG-4 streaming server with components such as elementary stream provider, sync layer and DMIF layer. Sync layer packets of each MPEG-4 elementary stream are prioritized and then selectively dropped at the sender to match the currently available bandwidth. Also, with the proposed adaptive transport module, the level of FEC protection is dynamically adjusted based on the underlying network condition. With preliminary verification over the emulated network testbed, it is shown that the proposed implementation can mitigate the impact of network fluctuation and thus improve the quality of streaming.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.1129-1132
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• 1999

This paper deals with the design and implementation of an Ethernet-based communication protocol to be used in PC-based I/O interface systems. Recently, the performance of PC systems is being highly improved and Ethernet is used as the stable communication network over the world. We develop a new protocol driver with the capability of accessing Ethernet directly using NDIS(Network Driver Interface Specification), the network interface standard of Windows O.S. in PC, and install it at the application layer of the protocol structure. Its major roles are the supplement of CSMA/CD algorithm, the effective use of the long data frame of Ethernet, and the real-time transmission of data frames. This paper represents the possibility of the real-time control network and systems based on PCs and Ethernet.

• 한국시뮬레이션학회논문지
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• 제8권4호
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• pp.125-136
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• 1999

In the forthcoming public ATM/B-ISDN, the efficient resource management with pre-planned transit networking which public domain NNI signaling is essential to maintain high network utilization and to assure QoS to the multimedia service users. For this purpose the transit networks must be managed according to the bearer service capability which is defined by ATM Forum and ITU-T. In this paper, we introduce an implementation of ATM transit networking with ATM VP-XC(Virtual Path cross-connect) and US(Network Management System). The functions of ATM VP-XC and NMS have been simulated with OPNET 6.1 modules. We implemented the F4 OAM functions of ATM VP connection according to the ITU-T 1.610 recommendation. Also, the ATM VP transit networking is managed by the NMS according to the connection management architecture of the TWN(Telecommunications Management Network) /TINA ( Telecommunications Information Networking Architecture).

• Journal of Information Processing Systems
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• 제5권1호
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• pp.25-32
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• 2009

It is absolutely essential to implement advanced IP network technologies such as QoS, Multicast, High Availability, and Security in order to provide real-time services like IPTV via IP backbone network. In reality, the existing commercial networks of internet service providers are subject to certain technical difficulties and limitations in embodying those technologies. On-going research efforts involve the experimental engineering works and implementation experience to trigger IPTV service on the premium-level IP backbone which has recently been developed. This paper introduces the core network technologies that will enable the deployment of a high-quality IPTV service, and then proposes a suitable methodology for application and deployment policies on each technology to lead the establishment and globalization of the IPTV service.

• 한국국방경영분석학회지
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• 제29권1호
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• pp.57-75
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• 2003

Policy-based networking offers a network manager the ability to manage the network in a holistic and dynamic fashion rather than force a network manager to manage the network by dealing with each device individually. Policy-based networking is focusing on users and applications instead of emphasizing devices and interfaces. An important part of the policy-based networking is to simplify the task of administration and management for different disciplines. The Defense Information System(DIS) of today are complex and heterogeneous systems. Operational needs are not a trivial task and Quality of Service(QoS) is not generally guaranteed. So, important data may be missed or congested by trivial data. Policy-based networking provide a way to support QoS and simplify the management of multiple devices deploying complex technologies. This paper suggest implementation of policy-based networking in DIS to improvement of performance, and implementation is progressed step by step. Especially this paper is focusing on the providing QoS with policy-based networking using Lightweight Directory Access Protocol(LDAP) Server.