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Query Pre-processing of Topological Constraints: Comparing a Composition-Based with Neighborhood-Based Approach [chapter]

M. Andrea Rodríguez, Max J. Egenhofer, Andreas D. Blaser
2003 Lecture Notes in Computer Science  
Individuals and the combination of the composition-and neighborhood-based strategies were implemented and compared with respect to their ability to reduce topological constraints, and with respect to the  ...  In both cases, the query processing approach is to solve a constraint satisfaction problem over a graph of binary topological relations.  ...  Composition-Based Pre-Processing The composition-based approach for query pre-processing is solely based on the algebraic properties of composition.  ... 
doi:10.1007/978-3-540-45072-6_21 fatcat:d2qyi4j5wjd4rpfch36kker3na

Image similarity retrieval by spatial constraints

Dimitris Papadias, Nikos Mamoulis, Dimitris Meretakis
1998 Proceedings of the seventh international conference on Information and knowledge management - CIKM '98  
This paper deals with queries involving the retrieval of images that contain certain object configurations.  ...  This query can be formulated as a constraint satisfaction problem (CSP) where the query variables are nodes of the corresponding constraint network and the image objects constitute the domain of each variable  ...  During the first pre-processing step, a path consistency algorithm [13] extracts the implicit constraints according to composition tables and computes the transitive closure of the query.  ... 
doi:10.1145/288627.288669 dblp:conf/cikm/PapadiasMM98 fatcat:nxsdseytmfchhfta2lir2pkuna

Constraint relaxation of the polygon-polyline topological relation for geographic pictorial query languages

Anna Formica, Elaheh Pourabbas, Maurizio Rafanelli
2013 Computer Science and Information Systems  
It focuses on the polygon-polyline topological relationship and proposes a computational model which is based on the notions of Operator Conceptual Neighborhood (OCN) graph and the relative 16-intersection  ...  The former is addressed to represent the conceptual topological neighborhood between pairs of Symbolic Graphical Objects and indicates how spatial constraints can be relaxed.  ...  They propose sixteen polyline-polygon topological relations as well as a conceptual neighborhood graph defined at two levels, basic and composite.  ... 
doi:10.2298/csis120302017f fatcat:66ugt36sdzehxmhl3jdbwoxslu

Program analysis as constraint solving

Sumit Gulwani, Saurabh Srivastava, Ramarathnam Venkatesan
2008 Proceedings of the 2008 ACM SIGPLAN conference on Programming language design and implementation - PLDI '08  
A constraint-based approach to invariant generation in programs translates a program into constraints that are solved using off-theshelf constraint solvers to yield desired program invariants.  ...  In this paper we show how the constraint-based approach can be used to model a wide spectrum of program analyses in an expressive domain containing disjunctions and conjunctions of linear inequalities.  ...  A denser neighborhood structure may result in lesser number of iterations of the while loop (i.e., a lesser number of queries to the constraint solver), but a larger sized query as a result of the condition  ... 
doi:10.1145/1375581.1375616 dblp:conf/pldi/GulwaniSV08 fatcat:75wivci7m5d6xee7ap3px6emna

Program analysis as constraint solving

Sumit Gulwani, Saurabh Srivastava, Ramarathnam Venkatesan
2008 SIGPLAN notices  
A constraint-based approach to invariant generation in programs translates a program into constraints that are solved using off-theshelf constraint solvers to yield desired program invariants.  ...  In this paper we show how the constraint-based approach can be used to model a wide spectrum of program analyses in an expressive domain containing disjunctions and conjunctions of linear inequalities.  ...  A denser neighborhood structure may result in lesser number of iterations of the while loop (i.e., a lesser number of queries to the constraint solver), but a larger sized query as a result of the condition  ... 
doi:10.1145/1379022.1375616 fatcat:dyn45ktbtfawbis474rfetonuy

Constraint-based Very Large-Scale Neighborhood search

Sébastien Mouthuy, Pascal Van Hentenryck, Yves Deville
2011 Constraints  
Experimental results show that our approach is comparable in time with respect to existing approaches, and that it allows to obtain state-of-theart solutions on two real-life problems exhibiting different  ...  VLSN search algorithms expressed by mean of our framework exhibits several benefits compared to existing approaches: 1) a more natural design of VLSN search algorithm, 2) a better reusability of existing  ...  ) . ) is compared to our compositional neighborhood (darker curve).  ... 
doi:10.1007/s10601-011-9114-7 fatcat:mxgk7frp6fg5hb7opxvyyq6psq

LS(Graph): a constraint-based local search for constraint optimization on trees and paths

Quang Dung Pham, Yves Deville, Pascal Van Hentenryck
2012 Constraints  
This paper proposes a constraint-based local search framework for COT/COP applications, bringing the compositionality, reuse, and extensibility at the core of constraint-based local search and constraint  ...  The main technical contribution is a connected neighborhood based on rooted spanning trees to find high-quality solutions to COP problems.  ...  This research is partially supported by the Interuniversity Attraction Poles Programme (Belgian State, Belgian Science Policy) and the FRFC project 2.4504.10 of the Belgian FNRS (National Fund for Scientific  ... 
doi:10.1007/s10601-012-9124-0 fatcat:z723syifhzf4fnyfnjar5wtxpq

Models and emerging trends of concurrent constraint programming

Carlos Olarte, Camilo Rueda, Frank D. Valencia
2013 Constraints  
It models systems of agents communicating by posting and querying partial information, represented as constraints over the variables of the system.  ...  We also describe the current efforts to endow CCP with bisimulation reasoning techniques as standardly done in process calculi. Section 7 concludes the paper.  ...  Special thanks to Jorge A. Perez for his careful remarks and suggestions.  ... 
doi:10.1007/s10601-013-9145-3 fatcat:7mx6xnyfcjad7musa373vockne

Point clouds can be represented as implicit surfaces for constraint-based haptic rendering

Adam Leeper, Sonny Chan, Kenneth Salisbury
2012 2012 IEEE International Conference on Robotics and Automation  
We present a constraint-based strategy for haptic rendering of arbitrary point cloud data.  ...  This method is resistant to sensor noise, makes no assumptions about surface connectivity or orientation, and data pre-processing is fast enough for use with streaming data.  ...  Chan is supported in part by a post-graduate scholarship from the National Science and Engineering Research Council (NSERC) of Canada.  ... 
doi:10.1109/icra.2012.6225278 dblp:conf/icra/LeeperCS12 fatcat:37g7cxf5uvhorlhls4xklotp3e

Unicast and Multicast Qos Routing with Soft Constraint Logic Programming [article]

Stefano Bistarelli, Ugo Montanari, Francesca Rossi, Francesco Santini
2008 arXiv   pre-print
We present a formal model to represent and solve the unicast/multicast routing problem in networks with Quality of Service (QoS) requirements.  ...  The second step consists in writing this graph as a program in Soft Constraint Logic Programming (SCLP): the engine of this framework is then able to find the best paths/trees by optimizing their costs  ...  One more enhancement that can be accomplished to reduce the size of a node's neighborhood (w.r.t. the given query) for the multicast distribution, is the inclusions of program facts that describe the topology  ... 
arXiv:0704.1783v3 fatcat:aqsrqz3bzzdyhdyf3e3mv7qg5i

Parallelism, Concurrency and Distribution in Constraint Handling Rules: A Survey [article]

Thom Fruehwirth
2018 arXiv   pre-print
CHR programs consist of guarded reactive rules that transform multisets of constraints. One of the main features of CHR is its inherent concurrency.  ...  Constraint Handling Rules is an effective concurrent declarative programming language and a versatile computational logic formalism.  ...  The active elements (nodes with excess flow) can be processed in parallel as long as their neighborhoods (set of nodes connected to them through an edge) do not overlap.  ... 
arXiv:1703.10959v4 fatcat:hw4zegjtzzdnvh4aw7pmcrbnkq

A Content-Based Approach to Searching and Indexing Spatial Configurations [chapter]

M. Andrea Rodríguez, Francisco A. Godoy
2002 Lecture Notes in Computer Science  
This approach uses a tree-based schema to index relations between objects' minimum bounding rectangles, it preprocesses the user query to obtain an ordered list of spatial constraints, and it explores  ...  This paper describes a new approach to retrieving spatial information whose novelty lies in using a content measure of topological relations to search and index spatial configurations.  ...  A traditional approach to this problem has been to use a spatial indexing schema over MRBs with heuristics to guide the search process of objects with specific topological constraints [2, 10, 11] .  ... 
doi:10.1007/3-540-45799-2_18 fatcat:kukpxgwfozgsngowhoospt2uuq

Neural Subgraph Matching [article]

Rex Ying, Zhaoyu Lou, Jiaxuan You, Chengtao Wen, Arquimedes Canedo, Jure Leskovec
2020 arXiv   pre-print
Subgraph matching is the problem of determining the presence and location(s) of a given query graph in a large target graph.  ...  However, existing techniques based on combinatorial matching and integer programming cannot handle matching problems with both large target and query graphs.  ...  ., 2012 ) make use of expensive pre-processing to store locations of many small 2-4 node components, and decompose the queries into these components.  ... 
arXiv:2007.03092v2 fatcat:iukf3larbbdt5mgyblw3lca5cq

Information extraction from sensor networks using the Watershed transform algorithm

Mohammad Hammoudeh, Robert Newman
2015 Information Fusion  
When compared to similar purpose schemes, such as "Logical Neighborhood", the proposed approach reduces the total query resolution overhead by up to 57.5%, reduces the number of nodes involved in query  ...  The challenge is to extract information from the gathered sensory data with a specified level of accuracy in a timely and power-efficient approach.  ...  We compare the performance of the proposed approach against that of the Logical Neighborhood.  ... 
doi:10.1016/j.inffus.2013.07.001 fatcat:kmhddq34yfcpvnehh7mh56jnie

Grid resource discovery based on semantically linked virtual organizations

Juan Li
2010 Future generations computer systems  
With the small-world topology constructed, resource-discovery queries will be propagated only between semantically related nodes, which greatly improves the efficiency and accuracy of resource discovery  ...  Specifically, we use a semantics-aware topology construction method to group similar nodes to form a semantic smallworld.  ...  When processing a query, the summaries are used in a pre-processing step to find peers that are likely to provide relevant answers to the query.  ... 
doi:10.1016/j.future.2009.07.011 fatcat:m3cfvenygbeyxoiqwsycf2mqb4
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