Results 1 - 10 of 12,188

A Simple Transmit Diversity Technique for Wireless Communications

by S. M. Alamouti , 1998
"... This paper presents a simple two-branch transmit diversity scheme. Using two transmit antennas and one receive antenna the scheme provides the same diversity order as maximal-ratio receiver combining (MRRC) with one transmit antenna, and two receive antennas. It is also shown that the scheme may ea ..."
Abstract - Cited by 2127 (0 self) - Add to MetaCart
This paper presents a simple two-branch transmit diversity scheme. Using two transmit antennas and one receive antenna the scheme provides the same diversity order as maximal-ratio receiver combining (MRRC) with one transmit antenna, and two receive antennas. It is also shown that the scheme may

Cooperative diversity in wireless networks: efficient protocols and outage behavior

by J. Nicholas Laneman, David N. C. Tse, Gregory W. Wornell - IEEE TRANS. INFORM. THEORY , 2004
"... We develop and analyze low-complexity cooperative diversity protocols that combat fading induced by multipath propagation in wireless networks. The underlying techniques exploit space diversity available through cooperating terminals’ relaying signals for one another. We outline several strategies ..."
Abstract - Cited by 2009 (31 self) - Add to MetaCart
protocols are efficient in the sense that they achieve full diversity (i.e., second-order diversity in the case of two terminals), and, moreover, are close to optimum (within 1.5 dB) in certain regimes. Thus, using distributed antennas, we can provide the powerful benefits of space diversity without need

The use of MMR, diversity-based reranking for reordering documents and producing summaries

by Jaime Carbonell, Jade Goldstein - In SIGIR , 1998
"... jadeQcs.cmu.edu Abstract This paper presents a method for combining query-relevance with information-novelty in the context of text retrieval and summarization. The Maximal Marginal Relevance (MMR) criterion strives to reduce redundancy while maintaining query relevance in re-ranking retrieved docum ..."
Abstract - Cited by 768 (14 self) - Add to MetaCart
documents and in selecting apprw priate passages for text summarization. Preliminary results indicate some benefits for MMR diversity ranking in document retrieval and in single document summarization. The latter are borne out by the recent results of the SUMMAC conference in the evaluation of summarization

DIVERSION ORDER 2013

by unknown authors
"... as shown on the Order map. The full width of that part of Footpath 3 Wymington from Ordnance Survey Grid Reference (OS GR) SP 9558 6384 (Point C on the map contained in this order) south west for approximately184 metres, then south for approximately 93 metres to a point on the field edge east of the ..."
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as shown on the Order map. The full width of that part of Footpath 3 Wymington from Ordnance Survey Grid Reference (OS GR) SP 9558 6384 (Point C on the map contained in this order) south west for approximately184 metres, then south for approximately 93 metres to a point on the field edge east

Space-time block codes from orthogonal designs

by Vahid Tarokh, Hamid Jafarkhani, A. R. Calderbank - IEEE Trans. Inform. Theory , 1999
"... Abstract — We introduce space–time block coding, a new paradigm for communication over Rayleigh fading channels using multiple transmit antennas. Data is encoded using a space–time block code and the encoded data is split into � streams which are simultaneously transmitted using � transmit antennas. ..."
Abstract - Cited by 1524 (42 self) - Add to MetaCart
of the space–time block code and gives a maximum-likelihood decoding algorithm which is based only on linear processing at the receiver. Space–time block codes are designed to achieve the maximum diversity order for a given number of transmit and receive antennas subject to the constraint of having a simple

Using Linear Algebra for Intelligent Information Retrieval

by Michael W. Berry, Susan T. Dumais - SIAM REVIEW , 1995
"... Currently, most approaches to retrieving textual materials from scientific databases depend on a lexical match between words in users' requests and those in or assigned to documents in a database. Because of the tremendous diversity in the words people use to describe the same document, lexical ..."
Abstract - Cited by 676 (18 self) - Add to MetaCart
Currently, most approaches to retrieving textual materials from scientific databases depend on a lexical match between words in users' requests and those in or assigned to documents in a database. Because of the tremendous diversity in the words people use to describe the same document

A simple cooperative diversity method based on network path selection

by Aggelos Bletsas, Ashish Khisti, David P. Reed, Andrew Lippman - IEEE J. SELECT. AREAS COMMUN , 2006
"... Cooperative diversity has been recently proposed as a way to form virtual antenna arrays that provide dramatic gains in slow fading wireless environments. However, most of the proposed solutions require distributed space–time coding algorithms, the careful design of which is left for future investi ..."
Abstract - Cited by 452 (14 self) - Add to MetaCart
investigation if there is more than one cooperative relay. We propose a novel scheme that alleviates these problems and provides diversity gains on the order of the number of relays in the network. Our scheme first selects the best relay from a set of available relays and then uses this “best ” relay

Measuring ISP Topologies with Rocketfuel

by Neil Spring, Ratul Mahajan, David Wetherall - In Proc. ACM SIGCOMM , 2002
"... To date, realistic ISP topologies have not been accessible to the research community, leaving work that depends on topology on an uncertain footing. In this paper, we present new Internet mapping techniques that have enabled us to directly measure router-level ISP topologies. Our techniques reduce t ..."
Abstract - Cited by 843 (28 self) - Add to MetaCart
the number of required traces compared to a brute-force, all-to-all approach by three orders of magnitude without a significant loss in accuracy. They include the use of BGP routing tables to focus the measurements, exploiting properties of IP routing to eliminate redundant measurements, better alias

Multiobjective evolutionary algorithms: a comparative case study and the strength pareto approach

by Eckart Zitzler, Lothar Thiele - IEEE TRANSACTIONS ON EVOLUTIONARY COMPUTATION , 1999
"... Evolutionary algorithms (EA’s) are often well-suited for optimization problems involving several, often conflicting objectives. Since 1985, various evolutionary approaches to multiobjective optimization have been developed that are capable of searching for multiple solutions concurrently in a singl ..."
Abstract - Cited by 813 (22 self) - Add to MetaCart
) evaluating an individual’s fitness dependent on the number of external nondominated points that dominate it, c) preserving population diversity using the Pareto dominance relationship, and d) incorporating a clustering procedure in order to reduce the nondominated set without destroying its characteristics

A Fast and Elitist Multi-Objective Genetic Algorithm: NSGA-II

by Kalyanmoy Deb, Amrit Pratap, Sameer Agarwal, T. Meyarivan , 2000
"... Multi-objective evolutionary algorithms which use non-dominated sorting and sharing have been mainly criticized for their (i) O(MN computational complexity (where M is the number of objectives and N is the population size), (ii) non-elitism approach, and (iii) the need for specifying a sharing param ..."
Abstract - Cited by 1815 (60 self) - Add to MetaCart
, is able to find much better spread of solutions and better convergence near the true Pareto-optimal front compared to PAES and SPEA - two other elitist multi-objective EAs which pay special attention towards creating a diverse Pareto-optimal front. Moreover, we modify the definition of dominance in order
Results 1 - 10 of 12,188