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» Selectivity Estimation in Spatial Databases
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84
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GLOBECOM
2006
IEEE
15 years 3 months ago
Non-Linear Precoding for OFDM Systems in Spatially-Correlated Frequency-Selective Fading MIMO Channels
— This paper presents non-linear precoding design in closed-loop multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) over spatiallycorrelated,...
Yu Fu, Witold A. Krzymien, Chintha Tellambura
EDBT
2006
ACM
129views Database» more  EDBT 2006»
15 years 9 months ago
Efficient Quantile Retrieval on Multi-dimensional Data
Given a set of N multi-dimensional points, we study the computation of -quantiles according to a ranking function F, which is provided by the user at runtime. Specifically, F compu...
Man Lung Yiu, Nikos Mamoulis, Yufei Tao
162
Voted
ICDE
2004
IEEE
85views Database» more  ICDE 2004»
15 years 11 months ago
Selectivity Estimation for String Predicates: Overcoming the Underestimation Problem
Queries with (equality or LIKE) selection predicates over string attributes are widely used in relational databases. However, state-of-the-art techniques for estimating selectivit...
Surajit Chaudhuri, Venkatesh Ganti, Luis Gravano
SIGMOD
1994
ACM
85views Database» more  SIGMOD 1994»
15 years 1 months ago
Adaptive Selectivity Estimation Using Query Feedback
In this paper, we propose a novel approach for estimating the record selectivities of database queries. The real attribute value distribution is adaptively approximated by a curve...
Chung-Min Chen, Nick Roussopoulos
SCALESPACE
2007
Springer
15 years 3 months ago
Segmentation Under Occlusions Using Selective Shape Prior
In this work, we address the problem of segmenting multiple objects, under possible occlusions, in a level set framework. A variational energy that incorporates a piecewise constan...
Sheshadri Thiruvenkadam, Tony F. Chan, Byung-Woo H...