检索结果-内蒙古大学图书馆

6th International Conference on Networking, ICN'07

作者： Zhao, Zhiwei Zhang, Xinming Sun, Peng Liu, Pengxi Department of Computer Science and Technology University of Science and Technology of China MOST Co-Key Laboratory of High Performance Computing and Its Application Anhui Province Hefei 230027 China

ISBN: (纸本)0769528058

Wireless sensor networks have been widely used in many important fields. Medium Access Control (MAC) protocols have a significant effect on the function and performance of sensor networks. At present, most MAC protocols use the same transmission power when sensor nodes send packets. However, the deployment of the sensor nodes is asymmetrical in wireless sensor networks, which will bring more energy consumption and unnecessary collisions. By jointing the MAC layer and physical layer of the senor nodes, and based on Sensor MAC (SMAC) [1] protocol, we propose a transmission power control MAC protocol in wireless sensor networks (transmission Power control in SMAC, PSMAC). The simulation results show that, compared with the SMAC protocol, our protocol has improved a lot in the delay of packets, reception rate, energy consumption and throughput of the networks. © 2007 IEEE.

关键词： Wireless sensor networks

来源：评论

学校读者我要写书评

暂无评论

A novel virtual anchor node-based localization algorithm for wireless sensor networks

A novel virtual anchor node-based localization algorithm for...

引用

6th International Conference on Networking, ICN'07

作者： Liu, Pengxi Zhang, Xinming Tian, Shuang Zhao, Zhiwei Sun, Peng Department of Computer Science and Technology University of Science and Technology of China MOST Co-Key Laboratory of High Performance Computing and Its Application Anhui Province Hefei 230027 China

ISBN: (纸本)0769528058

The accuracy of localization is a significant criterion to evaluate the practical utility of localization algorithm in wireless sensor networks. In mostly localization algorithms, one of the main methods to improve localization accuracy is to increase the number of anchor nodes. But the number of anchor nodes is always limited because of the hardware restrict, such as cost, energy consumption and so on. In this paper, we propose a novel algorithm with small extra logical overhead, which uses the shortest-hop path scheme to upgrade virtual anchor nodes, while the real number of physical anchors is the same as before. This algorithm firstly chooses out some special nodes from all the unknown ones to figure out more accurate positions of them, and then makes these ones as new virtual anchor nodes assist other unknowns in localizing together with the real anchors. The simulation results illustrate our algorithm has improved the accuracy of localization greatly. © 2007 IEEE.

关键词： Wireless sensor networks

来源：评论

学校读者我要写书评

暂无评论

A practical low interference topology control for mobile ad hoc networks

A practical low interference topology control for mobile ad ...

引用

6th International Conference on Networking, ICN'07

作者： Yu, Xiang Zhang, Xinming Que, Can Liu, Qiong Department of Computer Science and Technology University of Science and Technology of China Anhui Province - MOST Co-Key Laboratory of High Performance Computing and Its Application Hefei 230027 China

ISBN: (纸本)0769528058

The interference imposes a potential negative impact on the performance of a wireless network. A device is interfered if it receives a transmission not intended for it. In this paper, we introduce an explicit computation model of node interference based on its actual inducement on the physical layer. We prove that there exists an optimal algorithm to solve the corresponding topology control problem, constructing a network topology with minimum node interference. We also investigate the bad performance of existing methods of solving it and propose a revised algorithm, namely Low Interference-amount Neighborhood Tree (LINT), based on a new link cost metric. The simulation results illustrate that our model is able to reduce node interference effectively and maintain the network performance. © 2007 IEEE.

关键词： Ad hoc networks

来源：评论

学校读者我要写书评

暂无评论

A link reliability-aware route maintenance mechanism for mobile ad hoc networks

A link reliability-aware route maintenance mechanism for mob...

引用

6th International Conference on Networking, ICN'07

作者： Shi, Dong Zhang, Xinming Gao, Xuemei Zhu, Wenbo Zou, Fengfu Department of Computer Science and Technology University of Science and Technology of China MOST Co-Key Laboratory of High Performance Computing and Its Application Anhui Province Hefei 230027 China

ISBN: (纸本)0769528058

Hosts in mobile ad hoc networks (MANET) are capable of self-configuration and they can migrate at will, which makes the network topology highly dynamic. Thus, routes may break easily since the data session fails when one node moves out of the sensing range of its partner. Besides that, if overused, nodes tend to drain their power completely due to the limited battery life. That will result in a short life span of the network, which means serious performance degradation. The routing maintenance in traditional routing protocols such as Dynamic Source Routing (DSR) is triggered only after an active routing path breaks and in most cases, is realized by a route discovery process to build a new route. This kind of "after-the-event" routing maintenance raises the overhead heavily since considerable cost has to be spent in detecting the path break and establishing a new one. In this paper, we propose a new routing maintenance mechanism named link reliability-aware route maintenance (LRRM). Implemented on DSR, our mechanism tries to evaluate the link reliability of each hop actively and replace those debilitated nodes with robust ones through a local recovery if necessary. After that, the route change shall be informed to the source node by unicasting. Simulation results have proven LRRM's validity in extending network lifetime. Our mechanism also outperforms original DSR in throughput, delivery ratio and average end-to-end latency. © 2007 IEEE.

关键词： Mobile telecommunication systems

来源：评论

学校读者我要写书评

暂无评论

Real-time Java processor optimized for RTSJ

Proceedings of the ACM Symposium on Applied Computing

引用

Proceedings of the ACM Symposium on Applied computing 2007年 1540-1544页

作者： Chai, Zhilei Zhao, Wenke Xu, Wenbo Center of Intelligent and High Performance Computing School of Information Technology Southern Yangtze University Wuxi 214122 China Department of Computer Science and Engineering Fudan University 220# of Handan Rd. Shanghai 200433 China

ISBN: (纸本)1595934804;9781595934802

Due to the preeminent work of the real-time specification for Java(RTSJ), Java is increasingly expected to become the leading programming language in real-time systems. To provide a Java platform suitable for real-time applications, a real-time Java processor can execute Java bytecode directly is proposed in this paper. This processor provides efficient support in hardware for mechanisms specified in the RTSJ and offers a simpler programming model through ameliorating the scoped memory of the RTSJ. The most important characteristic of the processor is that its WCET(worst case execution time) of the bytecode execution is predictable. It is vital for the real-time systems. Copyright 2007 ACM.

关键词： Java programming language

来源：评论

学校读者我要写书评

暂无评论

Implementation of Monitoring and Information Service Using Ganglia and NWS for Grid Resource Brokers

Implementation of Monitoring and Information Service Using G...

引用

IEEE Asia-Pacific Conference on Services computing (APSCC)

作者： Chao-Tung Yang Tsui-Ting Chen Sung-Yi Chen High-Performance Computing Laboratory Department of Computer Science and Information Engineering Tunghai University Taichung Taiwan

Grid computing is increasingly used by organizations to achieve high performance computing and heterogeneous resources sharing. These grids may span several domain administrations via Internet. As a result of this, it may be difficult to monitor, control and manage those machines and resources. This paper aims at providing a multi-platform grid monitoring service which can monitor resources such as CPU speed and utilization, memory usage, disk usage, and network bandwidth in a real-time manner. Monitoring data is extracted form Ganglia and NWS tools then stored and transmitted in XML form and then used for displaying. All the information is displayed using real-time graphs.

关键词： Grid computing high performance computing Bandwidth Data mining computerized monitoring Condition monitoring Resource management XML Weather forecasting Chaos

来源：评论

学校读者我要写书评

暂无评论

A dynamic file replication strategy in data grids

A dynamic file replication strategy in data grids

引用

IEEE Region 10 International Conference TENCON

作者： Chao-Tung Yang Chun-Pin Fu Chien-Jung Huang High-Performance Computing Laboratory Department of Computer Science and Information Engineering Tunghai University Taichung Taiwan

As large amount of data that is produced by scientific experiments and simulations, data grid is a very important and useful technique to solve these kinds of problems in this region. Data replication is one technique that many researchers discuss in past years in data grid. It can create many copies of file and stored in the appropriate location to shorten the time of getting the file. In this paper, we propose a dynamical maintenance service of replication to maintain the data in grid environment. Replicas will be adjusted to the appropriate location for using. The BHR algorithm is a strategy to maintain replica dynamically. We point out a scenario that the BHR algorithm will cause a mistake when it operates. That mistake will limit the speed of transferring file. We propose the Dynamic Maintenance Service is aimed at overcoming the mistake proposed. The contributions of this paper are that the data grid environment will be more efficiency by using DMS algorithm. And the experimental results show that the DMS algorithm is more efficient than other replication strategies.

关键词： Bandwidth Delay Grid computing Computational modeling Distributed computing Resource management computer networks high performance computing Chaos Laboratories

来源：评论

学校读者我要写书评

暂无评论

G-BLAST: a grid-based solution for mpiBLAST on computational grids

G-BLAST: a grid-based solution for mpiBLAST on computational...

引用

IEEE Region 10 International Conference TENCON

作者： Chao-Tung Yang Tsu-Fen Han Heng-Chuan Kan High-Performance Computing Laboratory Department of Computer Science and Information Engineering Tunghai University Taichung Taiwan National Center for High-performance Computing Southern Business Unit Tainan Taiwan

The researches of bioinformatics have grown with each passing day so that more and more computing power is required for better performance. These requires usually solved by parallelism techniques, because cluster technology can reduce the execution time and increase alignment efficiency. For example, mpiBLAST is a parallelism solution of NCBI BLAST via MPI parallel programming. However, most laboratories can not build up powerful supercomputing environments. They usually connect dozen of personal computers to build cluster computing environments. Besides, cluster usually is limited by local environment that leads to extend equipments difficulty. The concepts of grid can solve these problems. Grid environments coordinate the resources of distributed virtual organizations and satisfy a great many computational demands. In this paper, we have deployed a biogrid framework called G-BLAST. G-BLAST was designed for sequence alignment to use grid environment and access mpiBLAST application from a server node. Because grid environment is a heterogeneous environment, G-BLAST is endowed with selection the most adaptive work nodes, dynamic fragmenting database, and self-adjust performance data abilities. Furthermore, we also deployed a grid service portal and a grid service GUI desk application for normal users to submit jobs and host administrators to maintain their own work nodes, and the interaction between this application and G-BLAST meets WSRF standards.

关键词： Grid computing Bioinformatics Biology computing Databases Sequences Microcomputers Application software Concurrent computing Distributed computing Power engineering computing

来源：评论

学校读者我要写书评

暂无评论

A One-Way File Replica Consistency Model in Data Grids

A One-Way File Replica Consistency Model in Data Grids

引用

IEEE Asia-Pacific Conference on Services computing (APSCC)

作者： Chao-Tung Yang Wen-Chi Tsai Tsui-Ting Chen Ching-Hsien Hsu High-Performance Computing Laboratory Department of Computer Science and Information Engineering Tunghai University Taichung Taiwan Department of Computer Science and Information Engineering Chung Hua University Hsinchu Taiwan

In recent years, grid technology, which is frequently used to solve the scientific problem, has ripened gradually. A large number of storage resources and computational power are combined to form a data grid network to deal with massive data of scientific experiments. Data replication generates huge data which are distributed in wide-area for researches around the globe. The files of grid environments can be modified by grid users might bring a critical problem of maintaining data consistency among the several replicas distributed in different machines. For that reason how to maintain the consistency of those files is a great challenge. In this paper, we propose a Oneway Replica Consistency model in data grid environments, which is used for consistency maintenance issue. Furthermore, we anticipate striking a balance between improving data access performance and replica consistency in data grids. This work can find out the more efficient ways of utilizing storage space is an important point.

关键词： Tin Grid computing Power engineering computing computer science Power engineering and energy Earth Availability Chaos Laboratories Data engineering

来源：评论

学校读者我要写书评

暂无评论

A Layered Optimization Approach for Redundant Reader Elimination in Wireless RFID Networks

A Layered Optimization Approach for Redundant Reader Elimina...

引用

IEEE Asia-Pacific Conference on Services computing (APSCC)

作者： Ching-Hsien Hsu Yi-Min Chen Chao-Tung Yang High-Performance Computing Laboratory Department of Computer Science and Information Engineering Tunghai University Taichung Taiwan Department of Computer Science and Information Engineering Chung Hua University Hsinchu Taiwan

The problem of redundant RFID reader elimination has instigated researchers to propose different optimization heuristics due to the rapid advance of technologies in large scale RFID systems. In this paper, we present a layered elimination optimization (LEO) which is an algorithm independent technique aims to detect maximum amount of redundant readers could be safely removed or turned off with preserving original RFID network coverage. A significant improvement of the LEO scheme is that number of "write-to-tag" operations could be largely reduced during the redundant reader identification phase. Moreover, LEO is a distributed scheme which does not need to collect global information for centralizing control, leading no communications and synchronizations among RFID readers. To evaluate the performance of the proposed techniques, we have implemented the LEO technique along with another redundant reader identification algorithm and other hybrid schemes. In experimental results, the LEO is shown to be effective and provides superior performance in terms of larger number of redundant reader could be detected and with lower algorithm overheads.

关键词： Radiofrequency identification Low earth orbit satellites Wireless sensor networks RFID tags Large-scale systems computer science Communication system control Radio frequency Temperature sensors computer networks

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：