检索结果-内蒙古大学图书馆

IEEE International Conference on Communications Workshops

作者： Shaohe Lv Weihua Zhuang Xiaodong Wang Xingming Zhou National Laboratory of Parallel and Distributed Processing National University of Defense Technology Department of Electrical and Computer Engineering University of Waterloo

ISBN: (纸本)9781612842325

We consider the greedy scheduling based on the physical model in wireless networks with successive interference cancellation (SIC). There are two major stages in a scheduling scheme, link selection (to decide which link is scheduled next) and time slot selection (to deciding which slot is allocated to a given link). Most available schemes take a first-fit policy in the latter and strive to achieve good performance by careful selection of link ordering with respect to interference. Due to the accumulation effect and sequential detection nature of SIC, however, it is difficult to evaluate the interference of a link. As a result, many existing scheduling schemes become less efficient. In this paper, we take a new look on the problem and focus to the time slot selection stage. We define tolerance margin to measure the saturation of a link set and present two heuristic policies: one is to schedule a link to a slot such that the resulting set of links has a maximum tolerance margin;the other is to choose a slot such that the increase of tolerance margin is minimum. Simulation results show that the performance of the proposed schemes is better than the first-fit policy and is close to the optimal solution.

关键词： Link scheduling Successive interference cancellation Physical interference model

来源：评论

学校读者我要写书评

暂无评论

An effective control scheme to ensure real-time causal order in large-scale distributed interactive simulations

An effective control scheme to ensure real-time causal order...

引用

2011 IEEE 3rd International Conference on Communication Software and Networks, ICCSN 2011

作者： Zhou, Hangjun Fu, Sha Department of Information Management Hunan University of Finance and Economics Chang Sha Hu Nan China Key Laboratory of Science and Technology for National Defence of Parallel and Distributed Processing School of Computer Science National University of Defense Technology Chang Sha Hu Nan China

ISBN: (纸本)9781612844855

When a large-scale distributed interactive simulation system is running on WAN, the sites usually disperse over a wide area in geography, which results in the simulation clock of each site is hardly to be accurately synchronized with that of other sites. The asynchronous clocks and large transmission latency on WAN bring on a problem for the large-scale simulations to preserve the real-time causal order delivery of received events at each site. In this article, we analyze the indirect way to compare the values of asynchronous simulation clocks at first, and then propose a novel scheme which can select the reconstructible causal control information for each message so as to ensure the causal ordering of events in real time. Experiments demonstrate that the scheme can weaken the effect of network latency, reduce the overhead of the transmission amount of control information and improve the causal order consistency in asynchronous distributed simulations. © 2011 IEEE.

关键词： Real time control

来源：评论

学校读者我要写书评

暂无评论

A causality based dynamic message ordering for DVEs on Wide Area Network

A causality based dynamic message ordering for DVEs on Wide ...

引用

IEEE International Conference on Communication Software and Networks

ISBN: (纸本)9781612844855

Due to the large message transmission latency in distributed Virtual Environments(DVEs) on Wide Area Net-work(WAN), the effectiveness of causality consistency control of message ordering is determined by not only causal order of messages but also the real-timeness. If merely causal order is considered, the real-time property of DVEs may not be ensured because of the unlimited waiting time for the delayed messages. While if only real-timeness is emphasized, there may be too many delayed messages, which have to be discarded, to maintain the quality of causal message ordering. Therefore, a trade-off between the quality of causal order delivery and real-timeness is necessary for DVEs. In this article, a novel causality based message ordering approach is presented. In general, this new approach dynamically balances the demands of causal order delivery and real-timeness. Experiment results demonstrate the approach can enhance the quality of causality, while simultaneously keep the real-time property of DVEs. © 2011 IEEE.

关键词： Wide area networks

来源：评论

学校读者我要写书评

暂无评论

A multi-layered emulation platform to verify the effectiveness of consistency control approaches about message ordering

A multi-layered emulation platform to verify the effectivene...

引用

IEEE International Conference on Communication Software and Networks

ISBN: (纸本)9781612844855

It is an important issue to preserve the consistent delivering order of messages at each site in distributed Virtual Environments(DVEs). Currently, the violations of message delivery order are inclined to happen in the large-scale and frequently interactive DVEs running on Wide Area Network(WAN). The inconsistent anomalies are characterized as unpredictable, unrepeatable and uncontrollable, which results in the severe problem for the development of the consistency control approaches. Meanwhile, it is also highly expensive to directly verify the proposed approaches on WAN. Therefore, in this paper, we design and establish an original multi-layered emulation platform in LAN, which can emulate the network latency of WAN and repeat the scenarios of violations. On the platform, the designers of consistency approaches don't have to spend efforts to realize the fundamental functions of the verification, but could pay more attention to the development and optimization of the control algorithms, which is very beneficial for the improvement of message ordering approaches. © 2011 IEEE.

关键词： Wide area networks

来源：评论

学校读者我要写书评

暂无评论

An Economical Power Management for High Performance Computers

An Economical Power Management for High Performance Computer...

引用

International Conference on Computational and Information Sciences (ICCIS)

作者： Huiquan Wang Xinhai Xu Jing Zhou Hao Zhou Guibin Wang National Laboratory for Parallel and Distributed Processing National University of Defense Technology Changsha Hunan P. R. China

The large amount of energy consumption of high performance computers represent significant financial cost. If we consider the specific situation of electricity price, a measure which makes the energy consumption the lowest is usually not the best on economy. This paper proposes an economical approach for designing a power management plan that reduces the assessment of energy consumption of high performance computers. By taking account of the electricity price in different periods during the day, we assign the workload to each period properly to make the electricity fee as low as possible. A simulation of the cases of a single task and multi-task demonstrates how our approach can be used. The results of the simulation show that our approach can save the electricity fee produced by high performance computers effectively. In the single task case, the proposed approach saves the electricity fee of 10.08% on average, and in the multi-task case the proportion of saved fee is 12.67%.

关键词： Electricity Supercomputers Energy consumption Mathematical model Power demand Equations

来源：评论

学校读者我要写书评

暂无评论

A Unified Co-Processor Architecture for Matrix Decomposition

引用

Journal of Computer Science & Technology 2010年第4期25卷 874-885页

作者：窦勇周杰邬贵明姜晶菲雷元武倪时策 National Laboratory for Parallel & Distributed Processing National University of Defense Technology National Laboratory for Parallel & Distributed Processing.National University of Defense Technology

QR and LU decompositions are the most important matrix decomposition algorithms. Many studies work on accelerating these algorithms by FPGA or ASIC in a case by case style. In this paper, we propose a unified framework for the matrix decomposition algorithms, combining three QR decomposition algorithms and LU algorithm with pivoting into a unified linear array structure. The QR and LU decomposition algorithms exhibit the same two-level loop structure and the same data dependency. Utilizing the similarities in loop structure and data dependency of matrix decomposition, we unify a fine-grained algorithm for all four matrix decomposition algorithms. Furthermore, we present a unified co-processor structure with a scalable linear array of processing elements （PEs）, in which four types of PEs are same in the structure of memory channels and PE connections, but the only difference exists in the internal structure of data path. Our unified co-processor, which is IEEE 32-bit floating-point precision, is implemented and mapped onto a Xilinx Virtex5 FPGA chip. Experimental results show that our co-processors can achieve speedup of 2.3 to 14.9 factors compared to a Pentium Dual CPU with double SSE threads.

关键词： co-processor matrix decomposition fine-grained parallel FPGA

来源：评论

学校读者我要写书评

暂无评论

An ordering-based approach to the evaluation of trust systems

An ordering-based approach to the evaluation of trust system...

引用

International Conference on Communication Software and Networks, ICCSN

作者： Wei Liu Yang-Bin Tang Huai-Min Wang Gang Lu School of Computer National University of Defense Technology Changsha Hunan China National Laboratory for Parallel and Distributed Processing Changsha Hunan China

Trust systems provide a promising way to build trust relationships among users in distributed and opening systems. However, it is difficult to make quantitatively comparative analysis on different trust systems because of the different application settings and the lack of effective measures. This paper constructs a framework of trust systems in terms of linear algebra, which helps us model and implement different systems in a uniform way. Besides, we propose an ordering-based approach to evaluating trust systems, then give two relevant ordering-base measures. The experiment results suggests that our method provides an effective way to analyze and evaluate trust systems.

关键词： Computational modeling Blogs

来源：评论

学校读者我要写书评

暂无评论

NBHU-based Method to Counter Quiet DDoS Attacks

NBHU-based Method to Counter Quiet DDoS Attacks

引用

2011 International Conference on Computer Science and Network Technology(2011计算机科学与网络技术国际会议 ICCSNT 2011)

作者： Jing Zhang Lin Chen Huaping Hu Hui Liu Computer School National University of Defense Technology Changsha China State Key Laboratory on Parallel and Distributed Processing National University of Defense Technolog

The Quiet DDoS attack becomes one of the most severely threat to the network safety, because this kind of attack completely adopts legal TCP flow while distributing its destination IP to evade various countermeasures deployed in the network. However, the high distributed degree of the destination IP becomes one characteristics of the attack. However, we think this characteristic make partially of the attack flow not match the behavior habit of network users. Inspired by this viewpoint, we propose a novel method to counter the Quiet DDoS attack based on the NBHU (network behavior habit of users). Furthermore, we carry on simulation of our method using NS2 platform, and the results show that this method can reduce the attack performance.

关键词： Quiet DDoS Attack Network Behavior Habit Counter

来源：评论

学校读者我要写书评

暂无评论

The prediction model based on RBF network in achieving elastic cloud

引用

Advances in Information Sciences and Service Sciences 2011年第11期3卷 67-78页

作者： Shi, Peichang Wang, Huaimin Ding, Bo Liu, Ran Wang, Tianzuo National Laboratory for Parallel and Distributed Processing School of Computer and Science National University of Defense Technology China Department of Electronics and Information Engineering Huazhong University of Science Technology China

Cloud needs to have rapid and elastic resources supply capability, because of the fluctuant resources demand of end-users. Multi-scale resources elastic binding is an important method to provide cloud services with rapid and elastic service capability. The most challenging problem in multi-scale resources elastic binding is how to predict the dynamic resource demand of end-users, and then decide when and to what extent multi-scale resources need elastic binding based on the prediction. In this paper, we present the prediction model based on RBF (Radial Basis Function) Network, which is used to predict end-users resource demand in advance. Compared with current prediction methods, it has faster prediction speed and higher prediction accuracy. Then we use traces data (the bandwidth demand of Web type of cloud services) collected from a real-world cloud provider: ChinaCache, as the training and testing data set to validate the method. Finally, we evaluate the predicted results using general prediction accuracy metrics. The results prove that the prediction model based on RBF network is able to resolve the decision problem in multi-scale resources elastic binding.

关键词： Radial basis function networks

来源：评论

学校读者我要写书评

暂无评论

Information recycling for social creativity

Information recycling for social creativity

引用

International Conference on Awareness Science and Technology (iCAST)

作者： Yilang Wu Takanobu Watanabe Distributed Parallel Processing Laboratory University of Aizu Aizu-wakamatsu Japan University Business Innovation Center University of Aizu Aizu-wakamatsu Japan

Social brainstorming has become a popular group creativity technique to create a large number of ideas for solving problems. The social computing, for its advance in information processing and network communication, collaborates the social intelligence and enhances the social creativity in brainstorming. However, facing the dilemma of quantity deficiency in idea pondering or quality submergence in idea deluge, cooperative participants essentially require needed information for their innovative work rather than unnecessary disturbance. Therefore, in purpose of enhancing the social creativity, we propose the needed information recycling based on multi-features in meta-data and also the similarity in social graph, helping participants keep a global and local image of previous work and focus on innovation tasks. Given an experimental demo, we discuss the essential merits of the novel brainstorming through the comprehensive but collaborative inter-merge of the social network and computer network, and conclude that the needed information recycling breeds the efficient and effective social creativity.

关键词： Collaboration Explosions

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：