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IEEE International Conference on Communications (ICC)

作者： H. J. Park E. Ayanoglu Center of Pervasive Communications and Computing Department of Electrical Engineering and Computer Science University of California Irvine USA

In this paper, we present the diversity order analysis of bit-interleaved coded multiple beamforming (BICMB) combined with the constellation precoding scheme. Multiple beamforming is realized by singular value decomposition of the channel matrix which is assumed to be perfectly known to the transmitter as well as the receiver. Previously, BICMB is known to have a diversity order bound related with the product of the code rate and the number of parallel subchannels, losing the full diversity order in some cases. In this paper, we show that BICMB combined with the constellation precoder and maximum likelihood detection achieves the full diversity order. We also provide simulation results that match the analysis.

关键词： Interleaved codes Array signal processing Analytical models Singular value decomposition Transmitters Bit error rate Communications Society Peer to peer computing Pervasive computing Cultural differences

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Translation of relational queries into Description Logic for semantic cache query processing

Translation of relational queries into Description Logic for...

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International Conference on Information and Emerging Technologies, ICIET

作者： Tariq Ali Muhammad Abdul Qadir Munir Ahmad Center for Distribute and semantic computing Department of Computer Science Mohammad Ali Jinnah University Islamabad Pakistan

Formulation of efficient algorithms to check implication and satisfibality for relational queries is an important research issue. Implication and satisfibality checking can be used to find query containment in semantic cache query processing and other similar applications. Description logic (DL) is a formalism used to model knowledge of a domain in the form of concepts and a rich set of associations between these concepts in the T-Boxes. Reasoning on these knowledge bases can be performed in order to find explicit relation as well as discover implicit relations. Sound and Complete subsumption algorithms exist for reasoning facts represented in Description Logic. The most common reasoning (which can be used for other sort of reasoning, too) is the determination of a subsumption relation between the logical expressions of T-boxes. In this paper, we propose an algorithm to translate relational queries in to description logic ALC(D), so that DL subsumption algorithms can be applied on these translated queries to find query containment. Working of the algorithm is demonstrated with the help of a case study. Conversion of relational query into DL will also help in optimization of cache size for the storage of semantics by eliminating redundant semantics in the cache. Hence, the sound and complete reasoning services of DL can be used for relational query containment.

关键词： Semantics Cognition Query processing Inference algorithms Servers Concrete Algorithm design and analysis

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Cost Efficient Erasure Coding based Routing in Delay Tolerant Networks

Cost Efficient Erasure Coding based Routing in Delay Toleran...

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IEEE International Conference on Communications

作者： Eyuphan Bulut Zijian Wang Boleslaw K. Szymanski Department of Computer Science and Center of Pervasive Computing and Networking Rensselaer Polytechnic Institute Troy NY USA

Routing in delay tolerant networks (DTNs) in which most of the nodes are mobile and intermittently connected is a challenging problem because of unpredictable node movements and lack of knowledge of future node connections. To ensure reliability against failures and increase the success rate of delivery, erasure coding technique is used to route messages in DTNs. In this paper, we study how the cost of erasure coding based routing protocols can be reduced. Specifically, we analyze the effects of different spraying algorithms, right parameter selection and splitting spraying phase on the cost of message delivery. We also perform simulations to evaluate the proposed approaches and demonstrate that the cost of erasure coding based routing can be reduced considerably with the proposed strategies while maintaining the delivery rate and delay objectives.

关键词： Costs Routing Disruption tolerant networking Peer to peer computing Tornadoes Spraying Delay US Government Communications Society computer science

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Behavior modeling with probabilistic context free grammars

Behavior modeling with probabilistic context free grammars

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International Conference on Information Fusion

作者： Sahin Cem Geyik Jierui Xie Boleslaw K. Szymanski Department of Computer Science and Center of Pervasive Computing and Networking Rensselaer Polytechnic Institute Troy NY USA

Identifying the behavioral patterns in a social network setting is beneficial to understand how people behave in certain application domains. Such patterns can also be utilized to characterize social signals such as social roles from interactions. In this work, we examine how probabilistic context free grammars (PCFGs) can be utilized to model interactions and role taking in a social network. We describe how to automatically build a PCFG given a set of interactions as the training data. Our experiments on the Mission Survival Corpus 1 (MSC-1) dataset show that PCFGs are a concise way of modeling social entity behaviors and are useful in understanding the probability distribution of interactions as well as the behavior types that are observed.

关键词： Grammar Context Measurement Production Probabilistic logic Training data Social network services

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An Upper Bound to the Marginal PDF of the Ordered Eigenvalues of Wishart Matrices and Its Application to MIMO Diversity Analysis

An Upper Bound to the Marginal PDF of the Ordered Eigenvalue...

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IEEE International Conference on Communications (ICC)

作者： H. J. Park E. Ayanoglu Center of Pervasive Communications and Computing Department of Electrical Engineering and Computer Science University of California Irvine USA

Diversity analysis of a number of multiple-input multiple-output (MIMO) applications requires the calculation of the expectation of a function whose variables are the ordered multiple eigenvalues of the Wishart matrices. To solve this, we need the marginal pdf of an arbitrary subset of the ordered eigenvalues. The marginal pdf shown in the literature is useful in numerical analysis, but not beneficial to diversity analysis. In this paper, we derive an upper bound to the marginal pdf of the eigenvalues. The derivation is based on the multiple integration of the well-known joint pdf, which is very complicated due to the exponential factors of the joint pdf. We suggest an alternative function that provides simpler calculation of the multiple integration. As a result, the marginal pdf is shown to consist of a multivariate polynomial with a given degree. By applying the marginal pdf to the calculation of the expectation, the diversity order for a number of MIMO systems can be calculated. Simulation results that support the analysis are presented.

关键词： Upper bound Eigenvalues and eigenfunctions MIMO Matrix decomposition Array signal processing Application software Numerical analysis Polynomials Analytical models Performance analysis

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Multiple beamforming with constellation precoding: Diversity analysis and Sphere Decoding

Multiple beamforming with constellation precoding: Diversity...

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Information Theory and Applications Workshop, ITA

作者： Hong Ju Park Boyu Li Ender Ayanoglu Center of Pervasive Communications and Computing Department of Electrical Engineering and Computer Science University of California Irvine USA

Multi-Input Multi-Output (MIMO) wireless communication systems commonly employ beamforming techniques with Singular Value Decomposition (SVD). In such systems, if no channel encoding is employed, the full diversity order provided by the channel is achieved when a single symbol is transmitted over multiple channels; however, this property is lost whenever multiple symbols are simultaneously transmitted. The full diversity order can be restored when channel coding is added to such a system. For example, when Bit-Interleaved Coded Modulation (BICM) is combined with this technique, the full diversity order of NM in an M × N MIMO channel, transmitting S parallel streams is possible; provided SR c ¿ 1 where R C is the BICM convolutional code rate. In this paper, we present multiple beamforming with constellation precoding which can achieve the full diversity order with both uncoded and BICM-coded SVD systems. An analytical proof of this property is provided. In addition, to reduce the computational complexity of Maximum Likelihood (ML) decoding, we introduce a Sphere Decoding (SD) technique. This technique achieves several orders of magnitude reduction in computational complexity not only with respect to conventional ML decoding, but also, with respect to conventional SD.

关键词： Array signal processing Maximum likelihood decoding MIMO Computational complexity Wireless communication Singular value decomposition Channel coding Interleaved codes Modulation coding Strontium

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Modelling data-driven CO2 sequestration using distributed HPC cyberinfrastructure 10

Modelling data-driven CO2 sequestration using distributed HP...

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2010 TeraGrid Conference, TG '10

作者： El-Khamra, Yaakoub Jha, Shantenu White, Christopher D. Craft and Hawkins Dept. of Petroleum Engineering Louisiana State University Texas Advanced Computing Center United States Department of Computer Science E-Science Institute Louisiana State University Edinburgh United States Craft and Hawkins Dept. of Petroleum Engineering Center for Computation and Technology Louisiana State University United States

ISBN: (纸本)9781605588186

In this paper we lay out the computational challenges involved in effectively simulating complex phenomena such as sequestering CO2 in oil and gas reservoirs. The challenges arise at multiple levels: (i) the computational complexity of simulating the fundamental processes;(ii) the resource requirements of the computationally demanding simulations;(iii) the need for integrating real-time data (intensive) and computationally intensive simulations;(iv) and the need to implement all of these in a robust, scalable and extensible approach. We will outline the architecture and implementation of the solution we develop in response to these requirements, and discuss results to validate claims that our solution scales to effectively solve desired problem sizes and thus provides the capability to generate novel scientific insight. Copyright 2010 ACM.

关键词： Carbon dioxide

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Preface

Lecture Notes in Computer Science (including subseries Lectu...

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Lecture Notes in computer science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 2011年 6844 LNCS卷

作者： Dehne, Frank Iacono, John Sack, Jörg-Rüdiger Carleton University School of Computer Science Parallel Computing and Bioinformatics Laboratory VISM Building 1125 Colonel By Drive OttawaONK1S 5B6 Canada Polytechnic Institute of NewYork University Department of Computer Science and Engineering 5 MetroTech Center NewYorkNY11201 United States Carleton University School of Computer Science Herzberg Laboratories Herzberg Building 1125 Colonel By Drive OttawaONK1S 5B6 Canada

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A comparative study on two large-scale hierarchical text classification tasks' solutions

A comparative study on two large-scale hierarchical text cla...

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International Conference on Machine Learning and Cybernetics

作者： Zhang, Jian Zhao, Hai Lu, Bao-Liang Department of Computer Science and Engineering Center for Brain-Like Computing and Machine Intelligence Shanghai Jiao Tong University 800 Dong Chuan Road Shanghai 200240 China MOE-Microsoft Key Laboratory for Intelligent Computing and Intelligent Systems Shanghai Jiao Tong University 800 Dong Chuan Road Shanghai 200240 China

ISBN: (纸本)9781424465262

Patent classification is a large scale hierarchical text classification (LSHTC) task. Though comprehensive comparisons, either learning algorithms or feature selection strategies, have been fully made in the text categorization field, few work was done for a LSHTC task due to high computational cost and complicated structural label characteristics. For the first time, this paper compares two popular learning frameworks, namely hierarchical support vector machine (SVM) and k nearest neighbor (k-NN) that are applied to a LSHTC task. Experiment results show that the latter outperforms the former in this LSHTC task, which is quite different from the usual results for normal text categorization tasks. Then this paper does a comparative study on different similarity measures and ranking approaches in k-NN framework for LSHTC task. Conclusions can be drawn that k-NN is more appropriate for the LSHTC task than hierarchical SVM and for a specific LSHTC task. BM25 outperforms other similarity measures and List Weak gains a better performance than other ranking approaches. We also find an interesting phenomenon that using all the labels of the retrieved neighbors can remarkably improve classification performance over only using the first label of the retrieved neighbors. © 2010 IEEE.

关键词： Learning algorithms

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An Empirical Study on Development Set Selection Strategy for Machine Translation Learning∗ 5

An Empirical Study on Development Set Selection Strategy for...

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Joint 5th Workshop on Statistical Machine Translation and MetricsMATR, WMT 2010 at the 48th Conference of the Associationfor Computational Linguistics, ACL 2010

作者： Hui, Cong Zhao, Hai Song, Yan Lu, Bao-Liang Center for Brain-Like Computing and Machine Intelligence Department of Computer Science and Engineering Shanghai Jiao Tong University China MOE-Microsoft Key Laboratory for Intelligent Computing and Intelligent Systems Shanghai Jiao Tong University 800 Dong Chuan Rd. Shanghai 200240 China Department of Chinese Translation and Linguistics City University of Hong Kong Hong Kong

ISBN: (纸本)9781932432718

This paper describes a statistical machine translation system for our participation for the WMT10 shared task. Based on MOSES, our system is capable of translating German, French and Spanish into English. Our main contribution in this work is about effective parameter tuning. We discover that there is a significant performance gap as different development sets are adopted. Finally, ten groups of development sets are used to optimize the model weights, and this does help us obtain a stable evaluation result. © 2010 Association for Computational Linguistics

关键词： Machine translation

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