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On Tree-Constrained Matchings and Generalizations

Stefan Canzar, Khaled Elbassioni, Gunnar W. Klau, Julián Mestre
2013 Algorithmica  
We consider the following Tree-Constrained Bipartite Matching problem: Given two rooted trees T1 = (V1, E1), T2 = (V2, E2) and a weight function w : V1 × V2 → R+, find a maximum weight matching M between  ...  We finally give an almost matching integrality gap example, and an inapproximability result showing that the dependence on ρ is most likely unavoidable.  ...  We thank Axel Mosig for introducing us to the problem and for helpful discussions.  ... 
doi:10.1007/s00453-013-9785-0 fatcat:yjcu3pwa3rgljd5iry4td3uafm

On Tree-Constrained Matchings and Generalizations [chapter]

Stefan Canzar, Khaled Elbassioni, Gunnar W. Klau, Julián Mestre
2011 Lecture Notes in Computer Science  
We consider the following Tree-Constrained Bipartite Matching problem: Given two rooted trees T1 = (V1, E1), T2 = (V2, E2) and a weight function w : V1 × V2 → R+, find a maximum weight matching M between  ...  We finally give an almost matching integrality gap example, and an inapproximability result showing that the dependence on ρ is most likely unavoidable.  ...  We thank Axel Mosig for introducing us to the problem and for helpful discussions.  ... 
doi:10.1007/978-3-642-22006-7_9 fatcat:exay2nca5rhpfif4jstbrl7s64

Subject Index

2005 Journal of Discrete Algorithms  
edit distances, 390 Tree inclusion Constrained tree inclusion, 431 Tree pattern matching Constrained tree inclusion, 431 Virtual paths Virtual path layouts optimizing total hop count on ATM tree  ...  on ATM tree networks, 101 Noncrossing bipartite matching Constrained tree inclusion, 431 NP-complete List total colorings of series-parallel graphs, 47; Hardness results for the center and median  ... 
doi:10.1016/s1570-8667(05)00042-0 fatcat:phytlwupp5hmtddg3ffue5546u

Generalized LCS

Amihood Amir, Tzvika Hartman, Oren Kapah, B. Riva Shalom, Dekel Tsur
2008 Theoretical Computer Science  
We also study the Longest Common Subforest problem for multiple trees including a constrained version, as well. We show N P -hardness for k > 2 unordered trees in the constrained LCS.  ...  We also give polynomial time algorithms for ordered trees and prove a lower bound for any decomposition strategy for k trees.  ...  We also present an O(kn k )-time algorithm for the constrained problem that is based on the algorithm of Zhang [25] for constrained tree edit distance and a K non-crossing matching algorithm.  ... 
doi:10.1016/j.tcs.2008.08.037 fatcat:delsujpgzrfhrfnggzl6tc6koi

Constrained tree inclusion

Gabriel Valiente
2005 Journal of Discrete Algorithms  
The tree matching problem is considered of given labeled trees P and T , determining if the pattern tree P can be obtained from the text tree T by deleting degree-one and degree-two nodes and, in the case  ...  Algorithms 8 (1) (1987) 106-112] are presented that solve the constrained tree inclusion problem in O(m 1.5 n) time on unordered trees with m and n nodes, and in O(mn) time on ordered trees, using O(mn  ...  Pinter and Michal Ziv-Ukelson on a preliminary version of this paper.  ... 
doi:10.1016/j.jda.2004.08.017 fatcat:7klol62bkvdz3k74fjgykttjae

On the complexity of graph tree partition problems

Roberto Cordone, Francesco Maffioli
2004 Discrete Applied Mathematics  
We consider di erent objectives, depending on the cost of the trees spanning the clusters.  ...  This paper concerns the optimal partition of a graph into p connected clusters of vertices, with various constraints on their topology and weight.  ...  Let us consider a generic instance of the Steiner Tree Problem on a grid graph.  ... 
doi:10.1016/s0166-218x(03)00340-8 fatcat:45rtgu27wrh5vjdewzmdb46xee

Online broadcasting and multicasting in WDM networks with shared light splitter bank

Weifa Liang, Yuzhen Liu
2007 2007 Fourth International Conference on Broadband Communications, Networks and Systems (BROADNETS '07)  
We then show that under either of the two proposed cost models, finding a cost-optimal broadcast or multicast tree for a broadcast or multicast request is NP-complete, and instead devise approximation  ...  number of light splitting and/or wavelength conversion switches, and they are shared by all incoming and outgoing signals at each installed node.  ...  Algorithm Degree Constrained Tree(V, E, d ) begin 1. H (X , Y , E ) ← H(X, find a maximum matching M in H ; 7.  ... 
doi:10.1109/broadnets.2007.4550475 dblp:conf/broadnets/LiangL07 fatcat:ilcfyyt7ijdglcl4jj4v7g3xua

Compiling pattern matching by term decomposition

Laurence Puel, Ascander Suarez
1990 Proceedings of the 1990 ACM conference on LISP and functional programming - LFP '90  
We present a method for compiling pattern matching on lazy languages based on previous work by Laville and Huet-Lévy.  ...  It consists of coding ambiguous linear sets of patterns using "Term Decomposition," and producing non ambiguous sets over terms with structural constraints on variables.  ...  We would like also to acknowledge helpful comments made by Gérard Huet and Hassan Aït-Kaci.  ... 
doi:10.1145/91556.91670 dblp:conf/lfp/PuelS90 fatcat:4m5hvoraovezhndfnokm6elsny

Compiling Pattern Matching by Term Decomposition

Laurence Puel, Ascander Suarez
1993 Journal of symbolic computation  
We present a method for compiling pattern matching on lazy languages based on previous work by Laville and Huet-Lévy.  ...  It consists of coding ambiguous linear sets of patterns using "Term Decomposition," and producing non ambiguous sets over terms with structural constraints on variables.  ...  We would like also to acknowledge helpful comments made by Gérard Huet and Hassan Aït-Kaci.  ... 
doi:10.1006/jsco.1993.1001 fatcat:b5jtnbb2njhl7cyiplezoupg3m

An O(log(n)) Fully Dynamic Algorithm for Maximum matching in a tree [article]

Manoj Gupta Indian Institute of Technology Kanpur)
2009 arXiv   pre-print
Query Time: O(1) to query the cardinality of maximum-matching and O(log(n)) to find if a particular edge is matched.  ...  In this paper, we have developed a fully-dynamic algorithm for maintaining cardinality of maximum-matching in a tree using the construction of top-trees. The time complexities are as follows: 1.  ...  Hence, we can see that if we know cardinality of certain constrained maximum-matchings for subtrees P and Q, we can generate the cardinality of constrained maximum-matchings for T .  ... 
arXiv:0901.2900v1 fatcat:ze6ze7rgvfdlxfuurd2vu4f6ye

Subject Index

2007 Journal of Discrete Algorithms  
Parameterized matching with mismatches, 135; Searching for a set of correlated patterns, 149; Efficient one-dimensional real scaled matching, 205; Generalized function matching, 514; Regular ex- pression  ...  the Stern-Brocot tree, 356 Exact/approximation algorithms On shredders and vertex connectivity augmentation, 91 Fingerprints Character sets of strings, 330 Finite automaton Regular expression constrained  ... 
doi:10.1016/s1570-8667(07)00076-7 fatcat:wfqxglrznfb6do3wyittd5pfbi

Finding a length-constrained maximum-sum or maximum-density subtree and its application to logistics

Hoong Chuin Lau, Trung Hieu Ngo, Bao Nguyen Nguyen
2006 Discrete Optimization  
We study the problem of finding a length-constrained maximum-density path in a tree with weight and length on each edge. This problem was proposed in [R.R. Lin, W.H. Kuo, K.M.  ...  In addition, we study the generalized problems of finding a length-constrained maximum-sum or maximum-density subtree in a given tree or graph, providing algorithmic and complexity results.  ...  LDP is an interesting generalization of LDS; for when the tree is a path, the problem on a tree is equivalent to the problem on a sequence.  ... 
doi:10.1016/j.disopt.2006.06.002 fatcat:gwjfnyhcmzcn5lpoevknd6lpjy

Geometry-based ranking for mobile 3D visual search using hierarchically structured multi-view features

David Ebri Mars, Hanwei Wu, Haopeng Li, Markus Flierl
2015 2015 IEEE International Conference on Image Processing (ICIP)  
A double hierarchy has been embedded in the data structure, namely the hierarchically structured multi-view features for each object and a tree hierarchy from multi-view vocabulary trees.  ...  As the 3D geometry information is incorporated in the multi-view vocabulary tree, it allows us to evaluate the consistency of the 3D geometry at low computational complexity.  ...  The reference method uses the scoring function in (3) and the epipolar-constrained 2D RANSAC for the geometric verification after vocabulary tree matching.  ... 
doi:10.1109/icip.2015.7351369 dblp:conf/icip/MarsWLF15 fatcat:wsu3imubqbcipb5sqnsm6sv7ki

Information Extraction Using the Structured Language Model [article]

Ciprian Chelba, Milind Mahajan
2001 arXiv   pre-print
semantic information and finally a constrained syntactic+semantic parser is trained on the parse trees resulting from the previous stage.  ...  The task of template filling is cast as constrained parsing using the SLM. The model is automatically trained from a set of sentences annotated with frame/slot labels and spans.  ...  Match and L-match SLM Parsing The trees produced by the SLM are binary trees.  ... 
arXiv:cs/0108023v1 fatcat:ddpd7u36fvb4ze6qxzhmvs5t24

Grammars++ for modelling information in text

Airi Salminen, Frank Wm. Tompa
1999 Information Systems  
In this paper, we formalize and illustrate the use of extended grammars for text databases.  ...  Extended grammars can also be used to specify database manipulation, including query, update, view definition, and index specification.  ...  Financial support from the Academy of Finland and the Natural Sciences and Engineering Research Council of Canada is gratefully acknowledged.  ... 
doi:10.1016/s0306-4379(99)00002-2 fatcat:7wzimlcehfe55dagyzkij4qu7y
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