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Topology awareness algorithm for virtual network mapping

Journal of Zhejiang University-science C(Computers and Electronics) 2012年第3期13卷 178-186页

作者： Xiao-ling LI Huai-min WANG Chang-guo GUO Bo DING Xiao-yong LI Wen-qi BI Shuang TAN National Key Laboratory of Parallel and Distributed Processing National University of Defense Technology.Changsha 410073China School of Computer National University of Defense TechnologyChangsha 410073China China Electronic Systems Engineering Corporation Beijing 100039China The Northern Institute of Electronic Equipment of China Beijing 100083China

Network virtualization is recognized as an effective way to overcome the ossification of the Internet. However, the virtual network mapping problem (VNMP) is a critical challenge, focusing on how to map the virtual networks to the substrate network with efficient utilization of infrastructure resources. The problem can be divided into two phases: node mapping phase and link mapping phase. In the node mapping phase, the existing algorithms usually map those virtual nodes with a complete greedy strategy, without considering the topology among these virtual nodes, resulting in too long substrate paths (with multiple hops). Addressing this problem, we propose a topology awareness mapping algorithm, which considers the topology among these virtual nodes. In the link mapping phase, the new algorithm adopts the k-shortest path algorithm. Simulation results show that the new algorithm greatly increases the long-term average revenue, the acceptance ratio, and the long-term revenue-to-cost ratio (R/C).

关键词： Network virtualization Ossification Virtual network （VN） mapping Substrate network （SN） Topology awareness Acceptance ratio

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Concurrent access control using subcarrier signature in heterogeneous MIMO-based WLAN

Concurrent access control using subcarrier signature in hete...

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5th International Workshop on Multiple Access Communications, MACOM 2012

作者： Shen, Hu Lv, Shaohe Sun, Yanqiang Dong, Xuan Wang, Xiaodong Zhou, Xingming National Key Laboratory of Parallel and Distributed Processing National University of Defense Technology Changsha 410073 China Institute of Network Information and Security National University of Defense Technology Changsha 410073 China

ISBN: (纸本)9783642349751

In recent WLAN standards (such as IEEE 802.11n), MIMO (Multiple Input Multiple Output) is deployed to provide high data transmission rate. It is however challenging to efficiently share the channel resources among different stations/users. In this paper, we study the MAC protocol in heterogeneous MIMO-based WLAN to effectively exploit the capability of concurrent transmission. We propose a novel subcarrier encoding method, which uses frequency signatures to perform the control message exchange between the AP and multiple stations simultaneously. Afterwards, a MAC protocol, HT-MIMO MAC, is presented to support concurrent transmission in both the uplink and downlink directions. HT-MIMO MAC supports link adaptation and is completely compatible with legacy stations. We evaluate the performance of the HT-MIMO MAC protocol and find that it outperforms the existing 802.11 MAC protocol with SU-MIMO and the downlink MU-MIMO MAC protocol in [9] with a remarkable throughput gains up to 86%. © 2012 Springer-Verlag.

关键词： MIMO systems

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Using NMFAS to identify key biological pathways associated with human diseases

Using NMFAS to identify key biological pathways associated w...

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2012 IEEE 6th International Conference on Systems Biology, ISB 2012

作者： Guo, Hao Zhu, Yunping Li, Dong He, Fuchu Liu, Qijun State Key Laboratory of Proteomics Beijing Proteome Research Centre Beijing Institute of Radiation Medicine Beijing China National Laboratory for Parallel and Distributed Processing National University of Deference and Technology Changsha China

ISBN: (纸本)9781467343985

Gene expression microarray enables us to measure the gene expression levels for thousands of genes at the same time. Here, we constructed the non-negative matrix factorization analysis strategy (NMFAS) to dig the underlying biological pathways related with various diseases by factorizing the pathway expression matrix, which was extracted from microarray matrix using pathway membership information, into the product of row and column vectors. We defined row vector as the pathway activity and column vector as the gene contribution weight. Via comparing the pathway activity of two different sample groups, we can identify significantly expressed pathways. We applied this strategy on two different cases: smoking and type 2 diabetes (DM2). We found 152 differentially expressed pathways by the comparison of pathway activity between smoker and never smoker, including pathways that have been validated in literature, such as "O-Glycans biosynthesis" and "Glutathione metabolism". We also found important genes related to smoking phenotype, such as NQO, HSPA1A, ALDH3A1. As for DM2 analysis, our results suggested 9 pathways were significantly expressed, including typical pathways like "Oxidative phosphorylation" and "mTOR signaling pathway", and found genes like CAPNS1, APP, COX7A1, COX7B, which might play important roles in the cellular regulations of DM2. In conclusion, Our strategy can be efficiently used to integrate gene expression profiles and biological pathway information to identify the key processes underlying human disease and can identify gene pathways missed by alternative approaches. © 2012 IEEE.

关键词： Non-negative matrix factorization

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Inducing taxonomy from tags: An agglomerative hierarchical clustering framework

Inducing taxonomy from tags: An agglomerative hierarchical c...

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8th International Conference on Advanced Data Mining and Applications, ADMA 2012

作者： Li, Xiang Wang, Huaimin Yin, Gang Wang, Tao Yang, Cheng Yu, Yue Tang, Dengqing National Laboratory for Parallel and Distributed Processing School of Computer Science National University of Defense Technology Changsha China College of Mechatronics Engineering and Automation National University of Defense Technology Changsha China

ISBN: (纸本)9783642355264

By amassing 'wisdom of the crowd', social tagging systems draw more and more academic attention in interpreting Internet folk knowledge. In order to uncover their hidden semantics, several researches have attempted to induce an ontology-like taxonomy from tags. As far as we know, these methods all need to compute an overall or relative generality for each tag, which is difficult and error-prone. In this paper, we propose an agglomerative hierarchical clustering framework which relies only on how similar every two tags are. We enhance our framework by integrating it with a topic model to capture thematic correlations among tags. By experimenting on a designated online tagging system, we show that our method can disclose new semantic structures that supplement the output of previous approaches. Finally, we demonstrate the effectiveness of our method with quantitative evaluations. © Springer-Verlag Berlin Heidelberg 2012.

关键词： Taxonomies

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A simple model for the energy-efficient optimal real-time multiprocessor scheduling

A simple model for the energy-efficient optimal real-time mu...

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2012 IEEE International Conference on Computer science and Automation Engineering, CSAE 2012

作者： Wu, Fei Jin, Shiyao Wang, Yuming College of Electronic and Electrical Engineering Shanghai University of Engineering Science Shanghai 201620 China National Laboratory of Parallel and Distributed Processing National University of Defense Technology Changsha 410073 China

ISBN: (纸本)9781467300865

As the energy consumption of embedded multiprocessor systems becomes increasingly prominent, it becomes an urgent problem of real-time energy-efficient scheduling in multiprocessor systems to reduce system energy consumption while meeting real-time constraints. In this paper, we introduce a unifying energy-efficient real-time scheduling theory with the Deadline Partitioning Fair Dynamic Voltage Frequency Scaling (DPF-DVFS) policy for multiprocessor systems. The proposed model can offer a unifying, extendable, on-line and simple method to realize energy-efficient real-time scheduling with low scheduling overhead. We then present an optimal energy-efficient scheduling algorithm DPF-DVFS-WRAP for periodic tasks. © 2012 IEEE.

关键词： Real time systems

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Cooperative spectrum sharing in relay-trading mode: A fairness view

Cooperative spectrum sharing in relay-trading mode: A fairne...

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4th International Conference on Cyber-Enabled distributed Computing and Knowledge Discovery, CyberC 2012

作者： Liu, Lixia Hu, Gang Xu, Ming Peng, Yuxing National Key Laboratory for Parallel and Distributed Processing School of Computer National University of Defense Technology Changsha 410073 China Department of Networks Engineering School of Computer National University of Defense Technology Changsha 410073 China

ISBN: (纸本)9780769548104

In the relay-trading mode of wireless cognitive radio networks the secondary user (SU) can achieve a promised spectrum access opportunity by relaying for the primary user (PU). How to utilize the exchanged resource efficiently and fairly is an interesting and practical problem. In this paper we proposed a cooperative spectrum sharing strategy (RT-CSS) for the relay-trading mode from the fairness view. The cooperative SUs are gathered in a cooperative sharing group (CSG), and contribution metric (CM) is proposed to measure each CSG member's contribution to CSG as well as benefit from CSG. The adjustment of CM can guarantee the fairness and efficiency of spectrum sharing. The numerical simulation shows that RT-CSS can achieve better performance than the sense-uncooperative mode. © 2012 IEEE.

关键词： Cognitive radio

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Security issues and solutions in cloud computing

Security issues and solutions in cloud computing

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32nd IEEE International Conference on distributed Computing Systems Workshops, ICDCSW 2012

作者： You, Pengfei Peng, Yuxing Liu, Weidong Xue, Shoufu National Key Laboratory for Parallel and Distributed Processing School of Computer Science National University of Defense Technology Changsha China Jiangsu Automation Research Institute Jiangsu China Air Defense Forces Academy CPLA Zhengzhou Henan China

ISBN: (纸本)9781467314237

Recently, Cloud computing, as one of the hottest words in IT world, has drawn great attention. Many IT companies such as IBM, Google, Amazon, Microsoft, Yahoo and others vigorously develop cloud computing systems and related products to customers. However, there are still some difficulties for customers to adopt cloud computing, in which many security issues exist, because data for a customer is stored and processed in cloud, not in a local machine. This paper briefly introduces cloud computing and its key concepts. In particularly, we intend to discuss security requirements and security issues involving data, application and virtualization in cloud computing, as well as current solutions to these issues. © 2012 IEEE.

关键词： Virtualization

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Topology-aware deployment of scientific applications in cloud computing

Topology-aware deployment of scientific applications in clou...

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2012 IEEE 5th International Conference on Cloud Computing, CLOUD 2012

作者： Fan, Pei Chen, Zhenbang Wang, Ji Zheng, Zibin Lyu, Michael R. National Laboratory for Parallel and Distributed Processing National University of Defense Technology Changsha 410073 China Dept. of Computer Science and Engineering Chinese University of Hong Kong Hong Kong Hong Kong

ISBN: (纸本)9780769547558

Nowadays, more and more scientific applications are moving to cloud computing. The optimal deployment of scientific applications is critical for providing good services to users. Scientific applications are usually topology-aware applications. Therefore, considering the topology of a scientific application during the development will benefit the performance of the application. However, it is challenging to automatically discover and make use of the communication pattern of a scientific application while deploying the application on cloud. To attack this challenge, in this paper, we propose a framework to discover the communication topology of a scientific application by pre-execution and multi-scale graph clustering, based on which the deployment can be optimized. Comprehensive experiments are conducted by employing a well-known MPI benchmark and comparing the performance of our method with those of other methods. The experimental results show the effectiveness of our topology-aware deployment method. © 2012 IEEE.

关键词： Cloud computing

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Research of Context Situation Awareness technology

Research of Context Situation Awareness Technology

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IEEE International Symposium on Object/Component/Service-Oriented Real-Time distributed Computing Workshops (ISORCW)

作者： Dianxi Shi Zhendong Wu Bo Ding Huining Yan National Key Laboratory for Parallel and Distributed Processing School of Computer Science National University of Defense Technology Changsha China

Context situation, which means a snapshot of the status of the real world, is formed by integrating a large amount of contexts collected from various resources. How to get the context situation and use the situation to provide better services is a challenging issue. In this paper, we focused on this challenge on the basis of the mobile cloud computing architecture. An abstract model is proposed in this paper to uniformly collect the context and send them to cloud. A rule-based large-scale context aggregation algorithm is also proposed which utilizes the MapReduce computing paradigm. Finally, a large-scale context management framework based on the abstract model and the context aggregation algorithm is proposed, and a real-time traffic demo is implemented to verify the validity of the framework.

关键词： Context Mobile handsets Real time systems Sensors Servers Mobile communication Context modeling

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A modified estimation scheme of EBT algorithm for RFID system

A modified estimation scheme of EBT algorithm for RFID syste...

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International Conference on Intelligent Control and Information processing (ICICIP)

作者： Ruisi Zhao Yulu Yang Parallel and distributed processing laboratory Department of Computer Science and Technology Nankai University Tianjin China

The paper proposes a scheme to improve the accuracy of tag estimation in the EBT algorithm in RFID system. In the proposed scheme, the mean value of the estimated tag number should be acquired before calculating the optimal prefix. And the circular queue is used to record the average tag number which has been acquired recently. Thought the computer simulation we proposed the optimal length of the queue and make an explanation why the circular queue should be used to store the average tag number. The proposed scheme makes a better system performance compared with the original EBT algorithm.

关键词： Estimation Heuristic algorithms Algorithm design and analysis Radiofrequency identification Binary trees Accuracy Computer simulation

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