• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.86-89
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• 1998

Multiple types of information in a multimedia service are delivered though multiple virtual connections on ATM network, while each virtual connection may be controlled independently. A multimedia service requires an associative relationship among multiple information streams to provide required harmonization. There may be required additional traffic descriptors to guarantee the required harmonization among multiple information streams in a multimedia service. For buffering of large bandwidth information stream(e.g., video), extremely large buffer size is necessary, but this approach should not be efficient way to compensate a severely delayed cells/blocks experienced at network. The best way to solve this problem will be minimization of relative-delayed-transfer of cells/blocks to application processes through ATM network control. To minimize a delayed transfer the mapping between relative delay parameter(i.e., associative Group QoS parameters) and per-VC traffic descriptor will be necessary. This paper is present additional functions and parameters to interpret the mapping between relative delay parameters(i.e., associative Group QoS parameters) and per-VC traffic descriptors in ATM API for multimedia application services.

• Journal of information and communication convergence engineering
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• 제16권1호
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• pp.31-37
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• 2018

In this work, we propose an analytic framework for evaluating the quality of service and dimensioning the link capacity in the gateway router of a smart farm with a greenhouse eco-management system. Specifically, we focus on the gateway router of an IoT network that provides an access service for smart farms. We design the link capacity of a gateway router that is used for the remote management of the greenhouse eco-management system to accommodate both time-critical and delay-tolerant traffic in a greenhouse LAN. For this purpose, we first investigate the ecosystem for smart farm, and we define the specification and requirements of the greenhouse eco-management system. Second, we propose a system model for the link capacity of a gateway that is required to guarantee the delay performance of time-critical applications in the greenhouse LAN. Finally, the validity of the proposed system is demonstrated through a series of numerical experiments.

• 전자공학회논문지A
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• 제31A권9호
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• pp.44-52
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• 1994

When a constructed multimedia application system transfers a various media of which quality of service is different, a previously constituted synchronization at source site generates the synchronization anomaly that the synchronization relation is broken by a delay or a data loss at destination. To solve the synchronization anomaly, we propose the “Multimedia synchronization scenario method : MSSM” which defines as one(1) event all objects generated at multimedia application and creates the optimal scenario of multimedia presentation under temporal constraints. The characteristics of MSSM can minimize the delay effect, guarantee the media stream continuity for preventing the media stretch, and provide the synchronization information to a user and/or a system. After deciding a synchronization possibility. MSSM confirm user its information. If there is a synchronization possibility. MSSM products optimal multimedia presentation scenario, and can present multimedia adaptively.

• Journal of information and communication convergence engineering
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• 제9권1호
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• pp.44-49
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• 2011

In RFID System, when multiple tags respond simultaneously, a collision can occur. A method that solves this collision is referred to anti-collision algorithm. In Gen-2 RFID system, if the slot-count size varies during a query round due to the collisions, a new query round begins with a QueryAdjust command. Anti-collision algorithm of Gen-2 RFID system is simple. But, it has the tag starvation problem that a tag may never be successfully identified because its responses always collide with others. Therefore, this paper proposes a scheme to guarantee the fair identification delay. In the proposed scheme, if the slot-count value changes due to the collisions, the reader broadcasts a CollisionRound command to begin a collision round. During the collision round, the reader identifies only tags that occurred collision during the previous query round.

• Journal of Communications and Networks
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• 제15권6호
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• pp.606-613
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• 2013

This paper proposes a complete solution of a contention-based medium access control in wireless local networks to provide station level quality of service guarantees in both downstream and upstream directions. The solution, based on the mature distributed coordination function protocol, includes a new fixed contention window backoff scheme, a tuning procedure to derive the optimal parameters, a super mode to mitigate the downstream bottleneck at the access point, and a simple admission control algorithm. The proposed system guarantees that the probability of the delay bound violation is below a predefined threshold. In addition, high channel utilization can be achieved at the same time. The numerical results show that the system has advantages over the traditional binary exponential backoff scheme, including efficiency and easy configuration.

• Journal of Information Processing Systems
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• 제8권4호
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• pp.589-602
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• 2012

With the increasing demand for real time applications in the Wireless Senor Network (WSN), real time critical events anticipate an efficient quality-of-service (QoS) based routing for data delivery from the network infrastructure. Designing such QoS based routing protocol to meet the reliability and delay guarantee of critical events while preserving the energy efficiency is a challenging task. Considerable research has been focused on developing robust energy efficient QoS based routing protocols. In this paper, we present the state of the research by summarizing the work on QoS based routing protocols that has already been published and by highlighting the QoS issues that are being addressed. The performance comparison of QoS based routing protocols such as SAR, MMSPEED, MCMP, MCBR, and EQSR has also been analyzed using ns-2 for various parameters.

• 한국멀티미디어학회논문지
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• 제25권2호
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• pp.325-334
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• 2022

Digital twin has the advantages of quality improvement and cost reduction, so it is widely applied to various industries. In this paper, a method to implement the major technologies of digital twin easily and quickly is presented. These include data management and relay servers, real-time monitoring applications including remote control interfaces, and direct connection protocols for video streaming. In addition, an algorithm for controlling a two-wheeled vehicle with a 2D interface is also proposed. The implemented system performs near real-time synchronization between the real environment and the virtual space. The delay time that occurs in remote control of the vehicle in the real environment was compared with the results of applying the proposed delay time reduction method. In addition, in the case of 2D interface-based control, an algorithm that can guarantee the user experience was implemented and applied to the actual environment and verified through experiments.

• 전기학회논문지P
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• 제54권3호
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• pp.129-133
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• 2005

In this paper we present a new PID controller design method using IMC design. The PID controller is derived based on the ${\infty}$-norm of sensitivity function to guarantee stability and performance robustness. This new PID controller is suitable for the plant with right half plane zeros or with time delay. The Simulation results show that the new method is superior to Ziegler-Nichols, Morari-Zafiriou, Mattezzoni-Rocco methods in respects in overshoot and settling time.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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• pp.168-172
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• 1994

This paper shows that the GPC with exponential weighting(GPCEW) can be applied to Electric furnace system which has large time delay. Stability of GPCEW can be guarantee from monotonically non-increasing property of Riccati difference equation. We show that the performance of GPCEW versus GPC and auto-tuning PID control is better than that of GPC or atito-tuning PID.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.90-93
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• 1998

컴퓨터 통신에서 실시간 멀티미디어 응용은 보장된 통신 서비스 성능을 요구하므로 이를 위해서는 트래픽이 버스트할 때 망 내에서 자원을 예약하여 접속시 피크율을 기반으로 망의 이용율을 높인다. 본 논문에서 결정론적 지연 범위을 이용하여 모든 접속에서 피크 율의 합이 링크 속도 보다 더 커질 때 버스트 상태의 트래픽에 대한 링크를 넘어 보장될 수 있음을 보인다. 또한 트래픽이 버스트할 때 새로운 결과는 연결수락된 접 속의 수를 증가시키므로 이러한 결과는 스위치에서 속도가 제어된 서비스 규율을 사용함으로써 단일 스위치로부터 망의 이용율을 개선할 수 있다.