检索结果-内蒙古大学图书馆

Network Coding-based Reliable Broadcast Transmission in Wireless networks

China Communications 2010年第2期7卷 71-77页

作者： Wang Jing Chi Kaikai Wang Xinmei School of Information Engineering Chang an University Xi an 710064 China College of Computer Science and Technology Zhejiang University of Technology Hangzhou 310023 China State Key Lab. of Integrated Service Networks Xidian University Xi an 710071 China

Recently, network coding has been applied to the loss recovery of reliable broadcast transmission in wireless networks. Since it was proved that fi nding the optimal set of lost packets for XOR-ing is a complex NP-complete problem, the available time-based retransmission scheme and its enhanced retransmission scheme have exponential computational complexity and thus are not scalable to large networks. In this paper, we present an efficient heuristic scheme based on hypergraph coloring and also its enhanced heuristic scheme to improve the transmission efficiency. Basically, our proposed schemes fi rst create a hypergraph according to the packet-loss matrix. Then our schemes solve the problem of generating XORed packets by coloring the edges of hypergraph. Extensive simulation results demonstrate that, the heuristic scheme based on hypergraph coloring and its enhanced scheme can achieve almost the same transmission efficiency as the available ones, but have much lower computational complexity, which is very important for the wireless devices without high computation capacity.

关键词： network coding reliable broadcast wireless networks transmission bandwidth computational complexity

来源：评论

学校读者我要写书评

暂无评论

Schedulability and end-to-end latency in distributed ECU networks: Formal modeling and precise estimation

Schedulability and end-to-end latency in distributed ECU net...

引用

6th Embedded Systems Week 2010, ESWEEK 2010 - 10th ACM International Conference on Compilers, Architecture and Synthesis for Embedded Systems, EMSOFT'10

作者： Rajeev, A.C. Mohalik, Swarup Dixit, Manoj G. Chokshi, Devesh B. Ramesh, S. General Motors Global Research and Development India Science Lab. Bangalore India Computer Engineering and Networks Lab ETH Zürich Zürich Switzerland

ISBN: (纸本)9781605589046

Embedded control systems in automobiles are typically implemented by a set of tasks deployed on multiple Electronic Control Units (ECUs) communicating via one or more buses like CAN or FlexRay. In the case of safety-critical systems, there are hard real-time bounds on the (i) response times of tasks/messages, and (ii) end-to-end latencies of certain task/message chains. These depend on various factors like the number of tasks (and messages) involved in the processing (and communication) sequence, parameters of these tasks/messages, scheduling policies, communication protocols, clock drifts, etc. Moreover, since the data transfer among tasks/messages is typically via asynchronous buffers that are overwritable and sticky, multiple semantics are possible for end-to-end latency. Hence, precise estimation of response times and end-to-end latencies in embedded systems is a non-trivial problem. In this paper, we propose a model-checking based technique to compute worst-case response times and end-to-end latencies. We consider a distributed system made of preemptively scheduled tasks and non-preemptively scheduled messages. Given a chain in the system, we estimate two different end-to-end latencies -LIFO and LILO- which are important in automotive domain. From a system description, we automatically synthesize a formal model based on a discrete event simulation formalism called Calendar Automata. It is then model-checked to compute response times and end-to-end latencies. Our technique is more scalable than the existing formal methods based techniques. We have illustrated this technique on reasonably large case-studies from the automotive domain.

关键词： Model checking

来源：评论

学校读者我要写书评

暂无评论

Secure communication model of WSN based on secret sharing

Secure communication model of WSN based on secret sharing

引用

International Conference on Computational Intelligence and Security

作者： Zhao, Xiaohui Pang, Liaojun Bi, Jingjuan Pei, Qingqi Li, Huixian Key Lab of Computer Networks and Information Security of Ministry of Education Xidian University Xi'an 710071 China Department of Computer Science and Engineering Northwestern Polytechnical University Xi'an 710072 China

ISBN: (纸本)9780769542973

In order to solve the problems in wireless sensor networks, such as node failure and losing of master key, a secure communication model based on secret sharing in wireless sensor networks is presented in this paper. In this model, with the secret sharing mechanism, the master key is divided into n parts which are distributed to the council nodes. Accordingly the council nodes can protect the master key, distribute keys to the nodes in the domain, periodically monitor the key node to avoid failure and improve the date output rate. © 2010 IEEE.

关键词： Sensor nodes

来源：评论

学校读者我要写书评

暂无评论

On selection of energy-efficient data aggregation node in wireless sensor networks

On selection of energy-efficient data aggregation node in wi...

引用

作者： Lee, Euisin Park, Soochang Yu, Fucai Kim, Sang-Ha Department of Computer Engineering Chungnam National University Daejeon Korea Republic of Key Lab of Broadband Optical Fiber Transmission and Communication Networks UESTC Chengdu China

In-network data aggregation is one of the most important issues for achieving energy-efficiency in wireless sensor networks since sensor nodes in the surrounding region of an event may generate redundant sensed data. The redundant sensed data should be aggregated before being delivered to the sink to reduce energy consumption. Which node should be selected as a Data Aggregation Node (DAN) for achieving the best energy efficiency is a difficult issue. To address this issue, this letter proposes a scheme to select a DAN for achieving energy-efficiency in an event region. The proposed scheme uses an analytical model to select the sensor node that has the lowest total energy consumption for gathering data from sensor nodes and for forwarding aggregated data to a sink, as a DAN. Analysis and simulation results show that the proposed scheme is superior to other schemes. Copyright © 2010 The Institute of Electronics, Information and Communication Engineers.

关键词： Energy utilization

来源：评论

学校读者我要写书评

暂无评论

Recognition of wobbling and nutating cone-shaped targets

Recognition of wobbling and nutating cone-shaped targets

引用

2010 IEEE International Conference on Intelligent Computing and Intelligent Systems, ICIS 2010

作者： Ding, Hanqing Guan, Yongsheng School of Computer and Communication Engineering Zhengzhou University of Light Industry Zhengzhou China State Key Lab. of Integrated Service Networks Xidian University Xi'an China

ISBN: (纸本)9781424465835

Recognition of wobbling and nutating cone-shaped targets is a major challenge in space target recognition area. In this paper, we develop a signal model of multiple scattering centers on the wobbling and nutating cone-shaped targets, analyze the micro-Doppler characteristics of their echo. It is concluded that the micro-Doppler features have remarkable differences due to their different micro-motion. Therefore, we apply viterbi algorithm to extract the micro-Doppler and micro-motion parameters, the simulation results demonstrate that the wobbling and nutating cone-shaped targets can be recognized effectively in this way. ©2010 IEEE.

关键词： Viterbi algorithm

来源：评论

学校读者我要写书评

暂无评论

A signal processing view on packet sampling and anomaly detection

A signal processing view on packet sampling and anomaly dete...

引用

IEEE INFOCOM 2010

作者： Brauckhoff, Daniela Salamatian, Kave May, Martin Computer Engineering and Networks Laboratory ETH Zurich Zurich Switzerland Computing Department Lancaster University Lancaster United Kingdom Paris Research Lab. Thomson Paris France

ISBN: (纸本)9781424458363

Anomaly detection methods typically operate on preprocessed traffic traces. Firstly, most traffic capturing devices today employ random packet sampling, where each packet is selected with a certain probability, to cope with increasing link speeds. Secondly, temporal aggregation, where all packets in a measurement interval are represented by their temporal mean, is applied to transform the traffic trace to the observation timescale of interest for anomaly detection. These preprocessing steps affect the temporal correlation structure of traffic that is used by anomaly detection methods such as Kalman filtering or PCA, and have thus an impact on anomaly detection performance. Prior work has analyzed how packet sampling degrades the accuracy of anomaly detection methods;however, neither theoretical explanations nor solutions to the sampling problem have been provided. This paper makes the following key contributions: (i) It provides a thorough analysis and quantification of how random packet sampling and temporal aggregation modify the signal properties by introducing noise, distortion and aliasing. (ii) We show that aliasing introduced by the aggregation step has the largest impact on the correlation structure. (iii) We further propose to replace the aggregation step with a specifically designed low-pass filter that reduces the aliasing effect. (iv) Finally, we show that with our solution applied, the performance of anomaly detection systems can be considerably improved in the presence of packet sampling. ©2010 IEEE.

关键词： Low pass filters

来源：评论

学校读者我要写书评

暂无评论

Camera calibration using lengths of corresponding line segments

Camera calibration using lengths of corresponding line segme...

引用

Pacific Rim Symposium on Image and Video Technology

作者： Wang, Ruiyan Jiang, Guang Quan, Long Wu, Chengke State Key Lab. of Integrated Service Networks School of Telecommunications Engineering Xidian University Xi'an China Department of Computer Science Hong Kong University of Science and Technology Hong Kong Hong Kong

ISBN: (纸本)9780769542850

Camera calibration using patterns is widely used in computer vision and industry. The accuracy of calibration depends on the accuracy of the pattern. A high accuracy pattern is usually difficult to manufacture in labs. In this paper, we propose to use two images of two identical industrial objects as natural calibration patterns. The corresponding line segments on the objects are used for a nonlinear calibration method, and only five intrinsic parameters of the camera are optimized in the procedure. The experiments show that the proposed method is both effective and practical. © 2010 IEEE.

关键词： Calibration

来源：评论

学校读者我要写书评

暂无评论

An efficient intruder deduction system with XOR

引用

Journal of Computational Information Systems 2010年第11期6卷 3535-3540页

作者： Yang, Yuanyuan Ma, Wenping Bai, Xiaofeng Liu, Weibo School of Telecommunications Engineering Xidian University Xi'an 710071 China Ministry of Education Key Lab. of Computer Networks and Information Security China

We propose a new intruder deduction system with XOR named IDX. By introducing the concept of abstract XOR term and its operation rules, IDX is able to eliminate complex equational reasoning of XOR. Moreover, it reduces the space complexity of the intruder deduction system from On to O2, which greatly improves the efficiency of the system. Finally, we prove that IDX is equivalent to traditional deduction system with XOR in terms of derivation. © 2010 Binary Information Press.

关键词： Formal methods

来源：评论

学校读者我要写书评

暂无评论

Distributed video coding for wireless visual sensor networks using low power Huffman coding

Distributed video coding for wireless visual sensor networks...

引用

Annual Conference on Information Sciences and Systems (CISS)

作者： Hassan Abid Saad Qaisar NUST School of Electrical Engineering &Computer Science Core Communications and Networks Laboratory (CoNNekT Lab) Islamabad Pakistan School of Electrical Engineering & Computer Science NUST Islamabad Pakistan

Practical distributed video coding is enthralling problem to solve for the research community. In this work, we present a distributed video codec to reduce energy consumption at the sensor node. Video compression is computationally intensive task, which makes computational energy a dominant factor in overall energy consumption. Specifically, we propose distributed video codec with low computational energy blocks of DCT, quantization and Huffman coding ensuring maximal compression. Our contribution in this paper is to provide analytical method for computing energy consumption at the sender node. An analytical performance evaluation in terms of expected energy dissipation is provided while using Imote2 platform. Furthermore, due to high processing capability of Imote2 platform, it is suitable for data-rich environments.

关键词： Wireless sensor networks Video coding Huffman coding Energy consumption Video codecs Video compression Distributed computing Discrete cosine transforms Quantization Performance analysis

来源：评论

学校读者我要写书评

暂无评论

Integrated magnetic array for bio-object sensing and manipulation

Integrated magnetic array for bio-object sensing and manipul...

引用

IEEE Biomedical Circuits and Systems (BIOCAS)

作者： Faisal T. Abu-Nimeh M. Salem Fathi Circuits Systems and Neural Networks Lab Dept. of Electrical & Computer Engineering Michigan State University East Lansing USA Dept. of Electrical & Computer Engineering Michigan State University East Lansing USA

Magnetic molecular-level interrogation, manipulation, and diagnosis are emerging as lab-on-chip platforms. These platforms entail low-cost, low-power, portable, and high efficiency integrated implementations. We introduce an all-integrated programmable 16 × 16 magnetic coil array chip for sensing and actuating small single bio-objects or collaboratively manipulating larger ones. The die-size is 1.5 × 1.5 mm 2 designed in bulk 0.5 μm CMOS technology. The integrated design does not require any external magnetic source. It relies on the Hall effect generated by the smallest permissible vertical coil inductors (in this reported technology, the smallest inductor's planar area is 6 μm × 6 μm). The coil array is selectively and dynamically controlled. Each cell, composed of the coil and its logical control circuitry, can detect small objects in the order of 1μm diameter as well as emit eight programmable magnetic field levels for manipulation. All array sensing and driving components are shared to reduce the overall imprint. Also, they are tuned to work at 900 MHz incorporating high-speed serial row/column switching for seamless pseudoparallel operation.

关键词： Coils Arrays Magnetic separation Sensors Oscillators Switches Magnetic circuits

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：