Results 1  10
of
856
Algorithms for coloring quadtrees
 Algorithmica
, 2002
"... We describe simple linear time algorithms for coloring the squares of balanced and unbalanced quadtrees so that no two adjacent squares are given the same color. If squares sharing sides are defined as adjacent, we color balanced quadtrees with three colors, and unbalanced quadtrees with four colors ..."
Abstract

Cited by 6 (0 self)
 Add to MetaCart
We describe simple linear time algorithms for coloring the squares of balanced and unbalanced quadtrees so that no two adjacent squares are given the same color. If squares sharing sides are defined as adjacent, we color balanced quadtrees with three colors, and unbalanced quadtrees with four
The SPLASH2 programs: Characterization and methodological considerations
 INTERNATIONAL SYMPOSIUM ON COMPUTER ARCHITECTURE
, 1995
"... The SPLASH2 suite of parallel applications has recently been released to facilitate the study of centralized and distributed sharedaddressspace multiprocessors. In this context, this paper has two goals. One is to quantitatively characterize the SPLASH2 programs in terms of fundamental propertie ..."
Abstract

Cited by 1399 (12 self)
 Add to MetaCart
The SPLASH2 suite of parallel applications has recently been released to facilitate the study of centralized and distributed sharedaddressspace multiprocessors. In this context, this paper has two goals. One is to quantitatively characterize the SPLASH2 programs in terms of fundamental properties and architectural interactions that are important to understand them well. The properties we study include the computational load balance, communication to computation ratio and traffic needs, important working set sizes, and issues related to spatial locality, as well as how these properties scale with problem size and the number of processors. The other, related goal is methodological: to assist people who will use the programs in architectural evaluations to prune the space of application and machine parameters in an informed and meaningful way. For example, by characterizing the working sets of the applications, we describe which operating points in terms of cache size and problem size are representative of realistic situations, which are not, and which re redundant. Using SPLASH2 as an example, we hope to convey the importance of understanding the interplay of problem size, number of processors, and working sets in designing experiments and interpreting their results.
Parallel Construction of Quadtrees and Quality Triangulations
, 1999
"... We describe e#cient PRAM algorithms for constructing unbalanced quadtrees, balanced quadtrees, and quadtreebased finite element meshes. Our algorithms take time O(log n) for point set input and O(log n log k) time for planar straightline graphs, using O(n + k/ log n) processors, where n measure ..."
Abstract

Cited by 71 (8 self)
 Add to MetaCart
We describe e#cient PRAM algorithms for constructing unbalanced quadtrees, balanced quadtrees, and quadtreebased finite element meshes. Our algorithms take time O(log n) for point set input and O(log n log k) time for planar straightline graphs, using O(n + k/ log n) processors, where n
Searching in metric spaces
, 2001
"... The problem of searching the elements of a set that are close to a given query element under some similarity criterion has a vast number of applications in many branches of computer science, from pattern recognition to textual and multimedia information retrieval. We are interested in the rather gen ..."
Abstract

Cited by 432 (38 self)
 Add to MetaCart
The problem of searching the elements of a set that are close to a given query element under some similarity criterion has a vast number of applications in many branches of computer science, from pattern recognition to textual and multimedia information retrieval. We are interested in the rather general case where the similarity criterion defines a metric space, instead of the more restricted case of a vector space. Many solutions have been proposed in different areas, in many cases without crossknowledge. Because of this, the same ideas have been reconceived several times, and very different presentations have been given for the same approaches. We present some basic results that explain the intrinsic difficulty of the search problem. This includes a quantitative definition of the elusive concept of “intrinsic dimensionality. ” We also present a unified
The Cost of Balancing Generalized Quadtrees
 In Proceedings of the 3rd Symposium on Solid Modeling and Applications
, 1995
"... A balanced quadtree has no adjacent elements of vastly different size. Refining a quadtree to balance it is a preliminary step in many finite element, mesh generation and computer graphics rendering algorithms. A cost of balancing is the creation of a somewhat larger quadtree. The paper considers se ..."
Abstract

Cited by 23 (0 self)
 Add to MetaCart
A balanced quadtree has no adjacent elements of vastly different size. Refining a quadtree to balance it is a preliminary step in many finite element, mesh generation and computer graphics rendering algorithms. A cost of balancing is the creation of a somewhat larger quadtree. The paper considers
Quadtrees  Hierarchical Grids
, 2010
"... In this chapter, we discuss quadtrees which is arguably one of the simplest and most powerful geometric datastructure. We begin in Section 2.1 by giving a simple application of quadtrees and describe a clever way for performing pointlocation queries quickly in such a quadtree. In Section 2.2, we ..."
Abstract
 Add to MetaCart
In this chapter, we discuss quadtrees which is arguably one of the simplest and most powerful geometric datastructure. We begin in Section 2.1 by giving a simple application of quadtrees and describe a clever way for performing pointlocation queries quickly in such a quadtree. In Section 2.2, we
Overlapping Linear Quadtrees and SpatioTemporal Query Processing
, 2000
"... indexing in spatiotemporal databases by using the technique of overlapping is investigated. Overlapping has been previously applied in various access methods to combine consecutive structure instances into a single structure, without storing identical substructures. In this way, space is saved wit ..."
Abstract

Cited by 57 (8 self)
 Add to MetaCart
without sacrificing time performance. A new access method, overlapping linear quadtrees is introduced. This structure is able to store consecutive historical raster images, a database of evolving images. Moreover, it can be used to support query processing in such a database. Five such spatio
Fast Adaptive Quadtree Mesh Generation
 in: Proceedings of the Seventh International Meshing Roundtable
, 1998
"... . A sizegoverned quadtree mesh generation method is presented in this paper to deal with planar domains of arbitrary shape. The tree decomposition provides a convenient control space, which can be used to determine the element sizes, as well as a neighboring space, which allows for the quick search ..."
Abstract

Cited by 12 (0 self)
 Add to MetaCart
. A sizegoverned quadtree mesh generation method is presented in this paper to deal with planar domains of arbitrary shape. The tree decomposition provides a convenient control space, which can be used to determine the element sizes, as well as a neighboring space, which allows for the quick
Dynamic Quadtree Mesh Refinement ∗
, 2007
"... Many algorithms exist for producing quality meshes when the input point cloud is known a priori. However, modern finite element simulations and graphics applications need to change the input set during the simulation dynamically. We show how to dynamically update the mesh under changes in the input ..."
Abstract
 Add to MetaCart
Many algorithms exist for producing quality meshes when the input point cloud is known a priori. However, modern finite element simulations and graphics applications need to change the input set during the simulation dynamically. We show how to dynamically update the mesh under changes in the input as points are added or removed one by one while maintaining quality guarantees with an optimal number of additional vertices. Our algorithm runs in optimal O(lg L/s) time per update, where L/s is the spread of the input. To obtain our result, we present a novel and simple quad and octtree parallel mesh generation algorithm, then apply selfadjusting computation techniques to dynamize the algorithm. 1
Speeding Up Construction of Quadtrees for Spatial Indexing
 VLDB
, 1999
"... Spatial indexes, such as those based on the quadtree, are important in spatial databases for efficient execution of queries involving spatial constraints, especially when the queries involve spatial joins. In this paper we present a number of techniques for speeding up the construction of two quadtr ..."
Abstract

Cited by 16 (1 self)
 Add to MetaCart
Spatial indexes, such as those based on the quadtree, are important in spatial databases for efficient execution of queries involving spatial constraints, especially when the queries involve spatial joins. In this paper we present a number of techniques for speeding up the construction of two
Results 1  10
of
856