Current efforts in multimedia communications emphasized on network infrastructure research and development in areas such as coding, compression, multicast, high-performance transport protocols, service interface, and ...
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ISBN:
(纸本)0819414832
Current efforts in multimedia communications emphasized on network infrastructure research and development in areas such as coding, compression, multicast, high-performance transport protocols, service interface, and resource management. These efforts intend to support a general service for efficient point-to-point and multipoint communications. However, other services, which were overlooked in the past, also demand network infrastructure support. For example, no specific way is currently proposed to perform conference services such as scheduling, announcement, and discovery. In the case of conference scheduling, the network resources and conference-related information need to be set up ahead of time. This requires scheduling support from the low-layer functions and protocols, including connection/configuration management, resource management and their associated protocols. This issue has not bee discussed seriously or included in any of the current proposed solution. In this paper, we will concentrate mainly on how to support the multimedia conferencing scheduling service in the network protocol layers. A novel scheme, which separates the connection phases, is proposed as the foundation to support the scheduling ability and scalability. The impact of scheduling to the API, reservation protocols, and resource management is also addressed.
TCP/IP (Transmission control Protocol/internet Protocol) is currently the de facto standard for local area networking in a client-server environment. It is a set of networking protocols that supports the communication...
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TCP/IP (Transmission control Protocol/internet Protocol) is currently the de facto standard for local area networking in a client-server environment. It is a set of networking protocols that supports the communication among heterogeneous computer systems connected by certain types of network media. Some of the common TCP/IP network media are local system memory loopback, Ethernet, Fiber Distributed Data Interface (FDDI), HYPERchannel, and Channel-to-Channel (CTC) connection in System/370 and System/390 environment. Two of the basic client-server facilities provided by TCP/IP are ftp program and telnet program. This paper introduces these two basic facilities of TCP/IP and presents the results of two simple client-server benchmarks for a larger-scale UNIX system using ftp and telnet over memory loopback, Ethernet, FDDI, HYPERchannel, and CTC connection for a local area network with up to sixteen hundred active users.
Neural network is recently showing a good promise for application in power electronics and motion controlsystems. So far, it has been applied for a few cases, mainly in the control of converters and drives, but its a...
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Neural network is recently showing a good promise for application in power electronics and motion controlsystems. So far, it has been applied for a few cases, mainly in the control of converters and drives, but its application in estimation is practically new. This paper explores the application of neural network for estimation of feedback signals in induction motor drive system. A feedforward neural network receives the machine terminal signals at the input and calculates flux, torque and unit vectors (cos θe and sin θe) at the output which are then used in the control of a direct vector-controlled drive system. The three-layer network has been trained extensively by NeuralWorks Professional ii/Plus program to emulate the DSP-based computational characteristics. The performance of the estimator is good and is comparable to that of DSP-based estimation. The drive system has been operated in the wide torque and speed regions independently with DSP-based estimator and neural network-based estimator, and are shown to have comparable performance. The neural network estimator has the advantages of faster execution speed, harmonic ripple immunity and fault tolerance characteristics compared to DSP-based estimator.
Emerging distributed multimedia applications have stringent performance requirements in terms of bandwidth, delay, delay-jitter, and loss rate. The Tenet real-Time protocol suite provides the services and mechanisms f...
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In this paper, we evaluate the performance of our trial hierarchical storage server by using simulation. Our system is composed of magnetic disk drives and an optical mass storage system (MSS). This is based on three ...
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ISBN:
(纸本)0819414808
In this paper, we evaluate the performance of our trial hierarchical storage server by using simulation. Our system is composed of magnetic disk drives and an optical mass storage system (MSS). This is based on three key techniques: (1) multiple readout control using the time slot synchronous method, (2) quick access control of the MSS by using magnetic disk drives, (3) a storage hierarchy method for video programs that has three configurations. To verify the effectiveness of our storage hierarchy, we construct a queuing network simulation model of the system based on experimentally measured values, and analyze the average waiting time for each of the three configurations of video programs. Selecting the appropriate video program configuration shortens the average waiting time to half of previous times, with a quick access of less than 1 second, and with 8 simultaneous readouts. Storage costs are reduced to about half that of magnetic disk drives only.
The proceedings contain 24 papers. The special focus in this conference is on network and Operating System Support for Digital Audio and Video. The topics include: Overview of the workshop;operating system support for...
ISBN:
(纸本)9783540584049
The proceedings contain 24 papers. The special focus in this conference is on network and Operating System Support for Digital Audio and Video. The topics include: Overview of the workshop;operating system support for the desk area network;adaptive real-time resource management supporting modular composition of digital multimedia services;micronet machines — new architectural approaches for multimedia end-systems;extending the chorus micro-kernel to support continuous media applications;an approach towards high performance multimedia threads;a scheduling discipline and admission control policy for xunet 2;modeling VC, VP and VN bandwidth assignment strategies in broadband networks;dynamic QOS control based on real-time threads;a multimedia enhanced transport service in a quality of service architecture;framework for implementing the next generation of communication protocols;performance bottlenecks in digital movie systems;ATM as a link in an ST-2 internet;probabilistic assignment of movies to storage devices in a video-on-demand system;operating system support for a video-on-demand file service;the evaluation of video layout strategies on a high-bandwidth file server;network support for dynamically scaled multimedia data streams and a unified framework for multicast forwarding.
Advanced networking technologies offer opportunities for new and better PDIS. The Information Highway attracts a great deal of attention, and yet a precise definition eludes us. There are two trends that are real. The...
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Advanced networking technologies offer opportunities for new and better PDIS. The Information Highway attracts a great deal of attention, and yet a precise definition eludes us. There are two trends that are real. The first, and the one that will have the most impact, is the expansion of the internet and commercial analogues. The other trend is the technological changes in higher performancenetworking elements. This trend presents problems and opportunities for PDIS researchers, unlike the largely operational difficulties of expanding access. We focus on Asynchronous Transfer Mode (ATM) as the information asphalt and discuss the effect of ATM on PDIS. The Information Highway, at least the ATM portion, offers the potential for new and improved types of information systems built from distributed elements. This potential comes from performance, programmability, and distributed control algorithms for network behavior. This makes the network a first-class element in information systems design rather than a problem which must be compensated for.< >
In this paper, we propose a new architecture for a neuro-fuzzy controller. This controller consists of two main elements : (i) a fuzzy controller which employs uniform symmetric triangular fuzzy (USTF) sets as members...
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In this paper, we propose a new architecture for a neuro-fuzzy controller. This controller consists of two main elements : (i) a fuzzy controller which employs uniform symmetric triangular fuzzy (USTF) sets as membership functions, and (ii) a backpropagation neural network which acts as a modifier of the rule base. The neuro-fuzzy controller is applied to a truck backer-upper (reversing) system, and its performance is compared with a conventional fuzzy logic controller.< >
Neural networks are is recently showing good promise for application in power electronics and motion controlsystems. So far, they have been applied to a few cases, mainly in the control of power converters and drives...
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Neural networks are is recently showing good promise for application in power electronics and motion controlsystems. So far, they have been applied to a few cases, mainly in the control of power converters and drives, but their application in estimation is practically new. This paper explores the application of neural networks for estimation of feedback signals in induction motor drive systems. A feedforward neural network receives the machine terminal signals at the input and calculates flux, torque and unit vectors (cos /spl theta//sub e/ and sin /spl theta//sub e/) at the output which are then used in the control of a direct vector-controlled drive system. The three-layer network has been trained extensively by the NeuralWorks Professional ii/Plus program to emulate the DSP-based computational characteristics. The performance of the estimator is good and is comparable to that of DSP-based estimation. The drive system has been operated in wide torque and speed regions independently with a DSP-based estimator and a neural network-based estimator, and are shown to have comparable performance. The neural network estimator has the advantages of faster execution speed, harmonic ripple immunity and fault tolerance characteristics compared to the DSP-based estimator.< >
With rapid development in multimedia communications, the problem of handling traffic with different quality of service requirements has become a crucial one, particularly in the area of internets. In this paper, the c...
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With rapid development in multimedia communications, the problem of handling traffic with different quality of service requirements has become a crucial one, particularly in the area of internets. In this paper, the case of a bridged FDDI network carrying multimedia traffic is studied in detail. In particular, various channel access mechanisms are proposed for the bridge, and the performance of inter- and intra-network traffic investigated. It is found that simply increasing the priority of the bridge is not effective. However, reserving part of the the synchronous bandwidth of FDDI for delay sensitive inter-network traffic results in acceptable packet loss and delay for both intra- and inter-network traffic, and it may be possible to further optimize the scheme by adapting the allocation of synchronous bandwidth according to traffic conditions.< >
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