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Implementing data cubes efficiently

by Venky Harinarayan, Anand Rajaraman, Jeffrey D. Ulman - In SIGMOD , 1996
"... Decision support applications involve complex queries on very large databases. Since response times should be small, query optimization is critical. Users typically view the data as multidimensional data cubes. Each cell of the data cube is a view consisting of an aggregation of interest, like total ..."
Abstract - Cited by 548 (1 self) - Add to MetaCart
total sales. The values of many of these cells are dependent on the values of other cells in the data cube..A common and powerful query optimization technique is to materialize some or all of these cells rather than compute them from raw data each time. Commercial systems differ mainly in their approach

Efficient Software-Based Fault Isolation

by Robert Wahbe, Steven Lucco, Thomas E. Anderson, Susan L. Graham , 1993
"... One way to provide fault isolation among cooperating software modules is to place each in its own address space. However, for tightly-coupled modules, this solution incurs prohibitive context switch overhead, In this paper, we present a software approach to implementing fault isolation within a sing ..."
Abstract - Cited by 777 (12 self) - Add to MetaCart
One way to provide fault isolation among cooperating software modules is to place each in its own address space. However, for tightly-coupled modules, this solution incurs prohibitive context switch overhead, In this paper, we present a software approach to implementing fault isolation within a

Efficient belief propagation for early vision

by Pedro F. Felzenszwalb, Daniel P. Huttenlocher - In CVPR , 2004
"... Markov random field models provide a robust and unified framework for early vision problems such as stereo, optical flow and image restoration. Inference algorithms based on graph cuts and belief propagation yield accurate results, but despite recent advances are often still too slow for practical u ..."
Abstract - Cited by 515 (8 self) - Add to MetaCart
use. In this paper we present new algorithmic techniques that substantially improve the running time of the belief propagation approach. One of our techniques reduces the complexity of the inference algorithm to be linear rather than quadratic in the number of possible labels for each pixel, which

HEED: A Hybrid, Energy-Efficient, Distributed Clustering Approach for Ad Hoc Sensor Networks

by Ossama Younis, Sonia Fahmy - IEEE TRANS. MOBILE COMPUTING , 2004
"... Topology control in a sensor network balances load on sensor nodes and increases network scalability and lifetime. Clustering sensor nodes is an effective topology control approach. In this paper, we propose a novel distributed clustering approach for long-lived ad hoc sensor networks. Our proposed ..."
Abstract - Cited by 590 (1 self) - Add to MetaCart
proposed approach does not make any assumptions about the presence of infrastructure or about node capabilities, other than the availability of multiple power levels in sensor nodes. We present a protocol, HEED (Hybrid Energy-Efficient Distributed clustering), that periodically selects cluster heads

The Contourlet Transform: An Efficient Directional Multiresolution Image Representation

by Minh N. Do, Martin Vetterli - IEEE TRANSACTIONS ON IMAGE PROCESSING
"... The limitations of commonly used separable extensions of one-dimensional transforms, such as the Fourier and wavelet transforms, in capturing the geometry of image edges are well known. In this paper, we pursue a “true” two-dimensional transform that can capture the intrinsic geometrical structure t ..."
Abstract - Cited by 513 (20 self) - Add to MetaCart
that is key in visual information. The main challenge in exploring geometry in images comes from the discrete nature of the data. Thus, unlike other approaches, such as curvelets, that first develop a transform in the continuous domain and then discretize for sampled data, our approach starts with a discrete

Option Pricing: A Simplified Approach

by John C. Cox, Stephen A. Ross, Mark Rubinstein - Journal of Financial Economics , 1979
"... This paper presents a simple discrete-time model for valumg optlons. The fundamental econonuc principles of option pricing by arbitrage methods are particularly clear In this setting. Its development requires only elementary mathematics, yet it contains as a special limiting case the celebrated Blac ..."
Abstract - Cited by 1016 (10 self) - Add to MetaCart
Black-&holes model, which has previously been derived only by much more difficult methods. The basic model readily lends itself to generalization in many ways. Moreover, by its very constructlon, it gives rise to a simple and efficient numerical procedure for valumg optlons for which premature

A Maximum Entropy approach to Natural Language Processing

by Adam L. Berger, Stephen A. Della Pietra , Vincent J. Della Pietra - COMPUTATIONAL LINGUISTICS , 1996
"... The concept of maximum entropy can be traced back along multiple threads to Biblical times. Only recently, however, have computers become powerful enough to permit the widescale application of this concept to real world problems in statistical estimation and pattern recognition. In this paper we des ..."
Abstract - Cited by 1366 (5 self) - Add to MetaCart
describe a method for statistical modeling based on maximum entropy. We present a maximum-likelihood approach for automatically constructing maximum entropy models and describe how to implement this approach efficiently, using as examples several problems in natural language processing.

Predicting Internet Network Distance with Coordinates-Based Approaches

by T. S. Eugene Ng, Hui Zhang - In INFOCOM , 2001
"... In this paper, we propose to use coordinates-based mechanisms in a peer-to-peer architecture to predict Internet network distance (i.e. round-trip propagation and transmission delay) . We study two mechanisms. The first is a previously proposed scheme, called the triangulated heuristic, which is bas ..."
Abstract - Cited by 631 (6 self) - Add to MetaCart
their own coordinates, these approaches allow end hosts to compute their inter-host distances as soon as they discover each other. Moreover coordinates are very efficient in summarizing inter-host distances, making these approaches very scalable. By performing experiments using measured Internet distance

A translation approach to portable ontology specifications

by Thomas R. Gruber - KNOWLEDGE ACQUISITION , 1993
"... To support the sharing and reuse of formally represented knowledge among AI systems, it is useful to define the common vocabulary in which shared knowledge is represented. A specification of a representational vocabulary for a shared domain of discourse — definitions of classes, relations, functions ..."
Abstract - Cited by 3365 (9 self) - Add to MetaCart
, including frame-based systems as well as relational languages. This allows researchers to share and reuse ontologies, while retaining the computational benefits of specialized implementations. We discuss how the translation approach to portability addresses several technical problems. One problem is how

A new approach to the maximum flow problem

by Andrew V. Goldberg, Robert E. Tarjan - JOURNAL OF THE ACM , 1988
"... All previously known efficient maximum-flow algorithms work by finding augmenting paths, either one path at a time (as in the original Ford and Fulkerson algorithm) or all shortest-length augmenting paths at once (using the layered network approach of Dinic). An alternative method based on the pre ..."
Abstract - Cited by 672 (33 self) - Add to MetaCart
All previously known efficient maximum-flow algorithms work by finding augmenting paths, either one path at a time (as in the original Ford and Fulkerson algorithm) or all shortest-length augmenting paths at once (using the layered network approach of Dinic). An alternative method based
Results 1 - 10 of 97,743