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- Anani, Adi, 1944-, et al.
(author)
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QoS-guaranteed packet scheduling in wireless networks
- 2009
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In: The Journal of China Universities of Posts and Telecommunications. - Amsterdam : Elsevier. - 1005-8885. ; 16:2, s. 63-67
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Journal article (peer-reviewed)abstract
- To guarantee the quality of service (QoS) of a wireless network, a new packet scheduling algorithm using cross-layer design technique is proposed in this article. First, the demand of packet scheduling for multimedia transmission in wireless networks and the deficiency of the existing packet scheduling algorithms are analyzed. Then the model of the QoS-guaranteed packet scheduling (QPS) algorithm of high speed downlink packet access (HSDPA) and the cost function of packet transmission are designed. The calculation method of packet delay time for wireless channels is expounded in detail, and complete steps to realize the QPS algorithm are also given. The simulation results show that the QPS algorithm that provides the scheduling sequence of packets with calculated values can effectively improve the performance of delay and throughput.
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- Chen, Yawen, et al.
(author)
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A Novel P-shape Tessellation Approach on Double-Loop Networks
- 2009
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In: 2009 IEEE INTERNATIONAL SYMPOSIUM ON IT IN MEDICINE & EDUCATION, VOLS 1 AND 2, PROCEEDINGS. - NEW YORK : IEEE. - 9781424439294 ; , s. 507-511
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Conference paper (peer-reviewed)abstract
- Double loop computer networks are widely used in the design and implementation of local area networks and parallel processing architectures. However the embedding problems on double-loop networks have not been well studied due to the complexity of double-loop networks. Since the traditional L-shape, designed to compute the diameter of double-loop networks, is not efficient to solve embedding problems, we propose a novel tessellation approach to partition the geometric plane of double-loop networks into a set of parallelogram shaped tiles, called P-shape. Our proposed tessellation technique, P-shape, is a useful theoretical tool for embedding meshes on double-loop networks, and can be extended to analyze other problems as a bridge between regular graphs and double-loop networks.
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| 9. |
- Pesonen, Joonas, et al.
(author)
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Methodology and tools for controller-networking codesign in WirelessHART
- 2009
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In: ETFA 2009 - 2009 IEEE Conference on Emerging Technologies and Factory Automation. - : IEEE conference proceedings. - 9781424427284
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Conference paper (peer-reviewed)abstract
- This paper describes a methodology for controller and communication scheduling co-design in control systems operating over wirelessHART networks. Data collection and dissemination operations are identified and scheduled to minimize the nominal communication latency. Techniques for improving the reliability of the network when link transmissions are unreliable are discussed, and a Markov-chain model for computing the latency distribution of data collection operations for a given schedule is proposed. The resulting latency models allow to represent the networked control loop as a jump-linear system, whose performance can be analyzed using techniques from stochastic control. We demonstrate how this framework can be used to co-design a networked LQG controller for a five-by-five MIMO control loop.
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| 10. |
- Soldati, Pablo, et al.
(author)
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Deadline-constrained transmission scheduling and data evacuation in wireless HART networks
- 2009
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In: Proceedings of ECC. - : IEEE. - 9783952417393 ; , s. 4320-4325
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Conference paper (peer-reviewed)abstract
- Real-time data delivery is a critical issue in wirelessHART networks. This paper develops a novel mathematical programming framework for joint routing and link scheduling of deadline-constrained traffic in wirelessHART networks. The general framework explores dynamic network flows on a time-expanded graph model and can provide flexible solutions for a variety of real-time data delivery problems. Data evacuation, an important communication paradigm in wirelessHART networks, is a special case of this general framework. We establish the lower bound on evacuation time for line, multi-line and binary tree networks. Moreover, we design a novel scheduling algorithm for data evacuation in binary tree networks, and prove that this scheduling algorithm can always achieve the lower bound on evacuation time. We evaluate our scheduling algorithm through numerical simulations, and results show that our algorithm can always minimize the evacuation time with the least number of channels.
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| 11. |
- Zhang, Deng-yin, 1964-, et al.
(author)
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An adaptive image watermarking algorithm based on perceptual model
- 2008
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In: Journal of Communication and Computer. - USA : David Publishing Company. - 1548-7709. ; 5:2, s. 1-7
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Journal article (peer-reviewed)abstract
- An adaptive image watermarking algorithm based on Watson’s perceptual model is proposed in this paper. The proposed watermarking algorithm fully considers image regional characteristic. First, the cover image is divided into different smooth regions according to its gray value. Then watermark adjustment factors of those different regions are calculated respectively based on Watson’s perceptual model. The watermark is embedded by the adjustment factors at last. Experiments show that the proposed algorithm has excellent imperceptibility and has little influence upon the eigenvalue of the cover image.
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| 12. |
- Zhang, Haibo, et al.
(author)
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Optimal Link Scheduling and Channel Assignment for Convergecast in Linear Wireless HART Networks
- 2009
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In: 2009 7TH INTERNATIONAL SYMPOSIUM ON MODELING AND OPTIMIZATION IN MOBILE, AD HOC, AND WIRELESS. - NEW YORK : Institute of Electrical and Electronics Engineers (IEEE). - 9781424449194 ; , s. 82-89
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Conference paper (peer-reviewed)abstract
- Convergecast, in which data from a set of sources is routed toward one data sink, is a critical functionality for wireless networks deployed for industrial monitoring and control. We address the joint link scheduling and channel assignment problem for convergecast in networks operating according to the recent WirelessHART standard. For a linear network with N single-buffer devices, we demonstrate that the minimum time to complete convergecast is 2N - 1 time-slots, and that the minimum number of channels required for this operation is inverted right perpendicularN/2inverted left perpendicular. When the devices are allowed to buffer multiple packets, we prove that the optimal convergecast time remains the same while the number of required channels can be reduced to inverted right perpendicularN - root N-(N-1)/2inverted left perpendicular. For both cases, we present jointly time- and channel-optimal scheduling policies with complexity O(N-2). Numerical results demonstrate that our schemes are also efficient in terms of memory utilization.
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