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Compact Representation for Answer Sets of n-ary Regular Queries [chapter]

Kazuhiro Inaba, Haruo Hosoya
2009 Lecture Notes in Computer Science  
In this paper, a compact data structure is introduced for representing the answer sets of n-ary queries defined by tree automata.  ...  We show that for any fixed n-ary regular query and an input tree t, the answer set can always be represented by an expression on · ∪ and * with every leaf expression being a singleton set of an input node  ...  Acknowledgments We would like to thank the anonymous reviewers for their helpful comments. This work was partly supported by the Japan Society for the Promotion of Science.  ... 
doi:10.1007/978-3-642-02979-0_13 fatcat:wyc4exggsbguxbmmjo4h4yzo6a

Compact representation for answer sets of n-ary regular queries

Kazuhiro Inaba, Haruo Hosoya
2010 Theoretical Computer Science  
In this paper, a compact data structure is introduced for representing the answer sets of n-ary queries defined by tree automata.  ...  We show that for any fixed n-ary regular query and an input tree t, the answer set can always be represented by an expression on · ∪ and * with every leaf expression being a singleton set of an input node  ...  Acknowledgments We would like to thank the anonymous reviewers for their helpful comments. This work was partly supported by the Japan Society for the Promotion of Science.  ... 
doi:10.1016/j.tcs.2010.05.026 fatcat:d4jzttyhbnfttc7bgehteg3imu

N-Ary Queries by Tree Automata [chapter]

Joachim Niehren, Laurent Planque, Jean-Marc Talbot, Sophie Tison
2005 Lecture Notes in Computer Science  
We show that run-based n-ary queries capture MSO, contribute algorithms for enumerating answers of n-ary queries, and study the complexity of the problem.  ...  We investigate n-ary node selection queries in trees by successful runs of tree automata.  ...  Thanks to the anonymous referees for the reference to L. Libkin's work [14] and acknowledge discussions with F. Neven, W. Martens, and T. Schwentick.  ... 
doi:10.1007/11601524_14 fatcat:et24hmhegncwhanlsg2byydnha

Efficient evaluation of n-ary conjunctive queries over trees and graphs

François Bry, Tim Furche, Benedikt Linse, Andreas Schroeder
2006 Proceedings of the eighth ACM international workshop on Web information and data management - WIDM '06  
N -ary conjunctive queries, i.e., queries with any number of answer variables, are the formal core of many Web query languages including XSLT, XQuery, SPARQL, and Xcerpt.  ...  We propose the first evaluation technique for n-ary conjunctive queries that applies to both tree-and graph-shaped data and retains the same complexity as the best known approaches that are restricted  ...  That is to say, the compact inmemory result representation in the memoization matrix is expanded to a set of valuations, i.e., a set of tuples associating answer variables with matching data nodes.  ... 
doi:10.1145/1183550.1183555 dblp:conf/widm/BryFLS06 fatcat:3svxmjuvwfe7thly2pv3f43gza

Learning n-Ary Node Selecting Tree Transducers from Completely Annotated Examples [chapter]

A. Lemay, J. Niehren, R. Gilleron
2006 Lecture Notes in Computer Science  
We present the first algorithm for learning n-ary node selection queries in trees from completely annotated examples by methods of grammatical inference.  ...  We propose to represent n-ary queries by deterministic n-ary node selecting tree transducers (n-NSTTs). These are tree automata that capture the class of monadic second-order definable nary queries.  ...  Our learning algorithms will have to use compact representations for huge sets of negative examples, i.e., complements nodes(t) n − q(t).  ... 
doi:10.1007/11872436_21 fatcat:prk27wdxjrdajormr7wp2lxdwu

Finitely Representable Databases

Stéphane Grumbach, Jianwen Su
1997 Journal of computer and system sciences (Print)  
We introduce a general definition of finite representation and define the concept of a query as a generalization of a query over relational databases.  ...  In particular, we show the failure of most of the well-known theorems of logic (compactness, completeness, etc.).  ...  ACKNOWLEDGMENTS The authors thank Victor Vianu and the referees for helpful comments.  ... 
doi:10.1006/jcss.1997.1524 fatcat:wnufsjymt5hhdemdf3ersmn4xe

Revisiting compact RDF stores based on k2-trees [article]

Nieves R. Brisaboa, Ana Cerdeira-Pena, Guillermo de Bernardo, Antonio Fariña
2020 arXiv   pre-print
We present a new compact representation to efficiently store and query large RDF datasets in main memory.  ...  , especially in datasets with a relatively large number of predicates.  ...  The k 2 -tree [11] is a compact representation of sparse binary matrices originally devised for Web graphs. Given an n × n matrix, it is represented as a k 2 -ary tree, for a fixed k.  ... 
arXiv:2002.11622v1 fatcat:hpd6tbupuvhqhg23qkp3g2gsxi

A Relational Tsetlin Machine with Applications to Natural Language Understanding [article]

Rupsa Saha, Ole-Christoffer Granmo, Vladimir I. Zadorozhny, Morten Goodwin
2021 arXiv   pre-print
In closed-domain question-answering, the first-order representation produces 10x more compact KBs, along with an increase in answering accuracy from 94.83% to 99.48%.  ...  The approach is further robust towards erroneous, missing, and superfluous information, distilling the aspects of a text that are important for real-world understanding.  ...  Knowledge of the Relation also allows us to narrow down possible entities for answering the query successfully.  ... 
arXiv:2102.10952v1 fatcat:i2z3vcm65fadxikqaunmr5oxoi

Learning With Subquadratic Regularization : A Primal-Dual Approach

Raman Sankaran, Francis Bach, Chiranjib Bhattacharyya
2020 Proceedings of the Twenty-Ninth International Joint Conference on Artificial Intelligence  
Subquadratic norms have been studied recently in the context of structured sparsity, which has been shown to be more beneficial than conventional regularizers in applications such as image denoising, compressed  ...  These algorithms are derived in a primal-dual framework, which have not been examined for subquadratic norms.  ...  Proceedings of the Twenty-Ninth International Joint Conference on Artificial Intelligence  ... 
doi:10.24963/ijcai.2020/268 dblp:conf/ijcai/WangXWZW20 fatcat:ih3cdae5rfcixesnvx6perhbn4

An Analysis of the Feasibility of Graph Compression Techniques for Indexing Regular Path Queries

Frank Tetzel, Hannes Voigt, Marcus Paradies, Wolfgang Lehner
2017 Proceedings of the Fifth International Workshop on Graph Data-management Experiences & Systems - GRADES'17  
Compact index representations enable the e cient storage of multiple indexes for varying RPQs.  ...  Regular path queries (RPQs) are a fundamental part of recent graph query languages like SPARQL and PGQL.  ...  Such an MR-index can be used if the same query has to be answered again or for answering RPQs whose regular path expression contains the index path.  ... 
doi:10.1145/3078447.3078458 dblp:conf/grades/TetzelVPL17 fatcat:5qf3n32b5bhq3j3hrknxmi27qu

Compact Querieable Representations of Raster Data [chapter]

Guillermo de Bernardo, Sandra Álvarez-García, Nieves R. Brisaboa, Gonzalo Navarro, Oscar Pedreira
2013 Lecture Notes in Computer Science  
There are no compact representations of raster data that provide efficient query capabilities.  ...  In this paper we propose compact representations to efficiently store and query raster datasets in main memory.  ...  Then we build a different set of random queries of each type for each dataset.  ... 
doi:10.1007/978-3-319-02432-5_14 fatcat:suo5hzpftjbdrb2b4poot2xz3e

Faster Dynamic Compressed d-ary Relations [chapter]

Diego Arroyuelo, Guillermo de Bernardo, Travis Gagie, Gonzalo Navarro
2019 Lecture Notes in Computer Science  
The $k^2$-tree is a successful compact representation of binary relations that exhibit sparseness and/or clustering properties. It can be extended to $d$ dimensions, where it is called a $k^d$-tree.  ...  We show that interpreting the $k^d$-tree as a dynamic trie on the Morton codes of the points, instead of as a dynamic representation of the bitvector as done in previous work, yields operation times that  ...  the ability to answer more complex queries, such as row/column queries, through a single traversal of the tree, that is required in k 2 -tree representations.  ... 
doi:10.1007/978-3-030-32686-9_30 fatcat:cpgvbqf2ynanzmg5ct2yknlebq

Grammar compressed sequences with rank/select support

Alberto Ordóñez, Gonzalo Navarro, Nieves R. Brisaboa
2017 Journal of Discrete Algorithms  
We introduce, instead, grammar-based representations for repetitive sequences, which use up to 6% of the space needed by statistically compressed representations, and support direct access and rank/select  ...  operations within tens of microseconds.  ...  We also set S n [0] = (0, 0, 0). To answer rank 0 (B, i), let S n [ i/s ] = (p, o, rnk) and set l = s · i/s − o.  ... 
doi:10.1016/j.jda.2016.10.001 fatcat:fggeakdtobfh5a4mel4g2musge

Extending General Compact Querieable Representations to GIS Applications

Nieves R. Brisaboa, Ana Cerdeira-Pena, Guillermo de Bernardo, Gonzalo Navarro, Óscar Pedreira
2019 Information Sciences  
In this paper we propose compact representations to efficiently store and query raster datasets in main memory.  ...  Current representations of raster data are usually designed for external memory or, when stored in main memory, lack efficient query capabilities.  ...  Given a binary matrix of size n × n, the k 2 -tree conceptually represents it as a k 2 -ary tree, for a given k 2 . The root of the conceptual tree corresponds to the complete matrix.  ... 
doi:10.1016/j.ins.2019.08.007 fatcat:7oce3v7n2rbwvl74g7unzzh6zi

GraCT: A Grammar Based Compressed Representation of Trajectories [chapter]

Nieves R. Brisaboa, Adrián Gómez-Brandón, Gonzalo Navarro, José R. Paramá
2016 Lecture Notes in Computer Science  
We present a compressed data structure to store free trajectories of moving objects (ships over the sea, for example) allowing spatio-temporal queries.  ...  Our method, GraCT, uses a $k^2$-tree to store the absolute positions of all objects at regular time intervals (snapshots), whereas the positions between snapshots are represented as logs of relative movements  ...  representation by encoding these data in smarter ways. We also plan to compare GraCT with state of the art indexes aimed at both time-slice and time-interval queries, and trajectories.  ... 
doi:10.1007/978-3-319-46049-9_21 fatcat:y6jkgs6yznephlduqqoe3vthli
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