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1,951
Polyline Join Evaluation Using Raster Approximation
"... The main subject of spatial joins are polygons and polylines. The processing of spatial joins can be greatly improved by the use of filters that reduce the need for examining the exact geometry of spatial objects in order to find the intersecting ones. Approximations of candidate pairs of spatial ob ..."
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Cited by 1 (1 self)
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The main subject of spatial joins are polygons and polylines. The processing of spatial joins can be greatly improved by the use of filters that reduce the need for examining the exact geometry of spatial objects in order to find the intersecting ones. Approximations of candidate pairs of spatial
A Raster Approximation for Processing of Polyline Joins
"... The main subject of spatial joins is polygons and polylines. The processing of spatial joins can be greatly improved by the use of filters that reduce the need for examining the exact geometry of spatial objects in order to find the intersecting ones. Approximations of candidate pairs of spatial obj ..."
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The main subject of spatial joins is polygons and polylines. The processing of spatial joins can be greatly improved by the use of filters that reduce the need for examining the exact geometry of spatial objects in order to find the intersecting ones. Approximations of candidate pairs of spatial
Smooth Polylines on Polygon Meshes
, 2003
"... this paper a simple and efficient algorithm for building smooth polylines on triangulated 2Dmanifold polygonal meshes is introduced. The algorithm combines geometrical optimization with topological modifications in order to iteratively smooth an initial crude polyline. One key feature of this algor ..."
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Cited by 5 (2 self)
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this paper a simple and efficient algorithm for building smooth polylines on triangulated 2Dmanifold polygonal meshes is introduced. The algorithm combines geometrical optimization with topological modifications in order to iteratively smooth an initial crude polyline. One key feature
Filtering with Raster Signatures
"... Efficient evaluation of spatial queries is an important issue in spatial database. Among spatial operations, spatial join is very useful, intersection being the most common predicate. However, the exact intersection test of two spatial objects is the most timeconsuming and I/Oconsuming step in pro ..."
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(polygons, polylines and points), and to be used as filter in the second step of the MultiStep Query Processor. We have also executed experimental tests over real datasets, the results having demonstrated the effectiveness of our approach.
Survey of Polygonal Surface Simplification Algorithms
, 1997
"... This paper surveys methods for simplifying and approximating polygonal surfaces. A polygonal surface is a piecewiselinear surface in 3D defined by a set of polygons ..."
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Cited by 228 (3 self)
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This paper surveys methods for simplifying and approximating polygonal surfaces. A polygonal surface is a piecewiselinear surface in 3D defined by a set of polygons
Multiscale Curvature Matching for Smooth Polylines Author:
"... Abstract: The objective of matching polygonal curves is to determine their perceptual similarity, the notion of which is often based upon the similarity transformations. But searching the transformation space is costly and errorprone, depending on the set of transformations that are allowed. Curv ..."
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contained definitions for the curvature of polygonal curves, which use the concept of scale space, a metrical distance measure for those curvature functions and an efficient algorithm to compute the respective similarity distance of two polygonal curves under the above mentioned transformations.
Partition Based SpatialMerge Join
, 1996
"... This paper describes PBSM (Partition Based SpatialMerge), a new algorithm for performing spatial join operation. This algorithm is especially effective when neither of the inputs to the join have an index on the joining attribute. Such a situation could arise if both inputs to the join are interme ..."
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Cited by 185 (12 self)
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are intermediate results in a complex query, or in a parallel environment where the inputs must be dynamically redistributed. The PBSM algorithm partitions the inputs into manageable chunks, and joins them using a computational geometry based planesweeping technique. This paper also presents a performance study
Cognitive robot mapping with polylines and an absolute space representation
 In IEEE International Conference on Robotics and Automation
, 2004
"... Abstract—Robot mapping even today is one of the most challenging problems in robot programming. Most successful methods use some form of occupancy grid to represent a mapped region. This approach becomes problematic if the robot is mapping a large environment, the map quickly becomes too large for p ..."
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Cited by 1 (0 self)
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, the grids are converted to a polygonal representation. This polygonal representation is stored as rooms and hallways as a set of Absolute Space Representations (ASRs) representing the space connections. Using this representation makes navigation and localization easier for the robot to process. I.
On the Conversion of Filled Polygonal Regions from Raster to Vector Representation
, 1987
"... The usual method for specifying a fill pattern is to give a small sample of the pattern in raster form. A plotting routine then repeats this pattern over an arbitrary region. It is difficult for devices such as pen plotters to accurately reproduce pictures specified in this manner. By converting the ..."
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the original fill pattern to vector form, it is possible to fill arbitrary polygonal regions with a good approximation of most raster patterns.
Approximate Spatial Query Processing Using Raster Signatures
 In: Proceedings of VI Brazilian Symposium on GeoInformatics
, 2004
"... Abstract: Nowadays, the database characteristics, such as the huge volume of data, the complexity of the queries, and even the data availability, can demand minutes or hours to process a query. On the other hand, in many cases it may be enough to the user to get a fast approximate answer, since it h ..."
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Cited by 2 (2 self)
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it has the desired precision. The challenge to give to the user an exact query answer within a reasonable time becomes even bigger in the spatial database field. This work proposes the use of the Four Color Raster Signature (4CRS) for approximate query processing. The main goal is to reduce the time
Results 1  10
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1,951