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On the number of databases and closure operations

G. Burosch, J. Demetrovics, G.O.H. Katona, D.J. Kleitman, A.A. Sapozhenko
1991 Theoretical Computer Science  
Klzitmai; and A.A. Sapoozhenko, On the number of databases and closure operations (Note), Theorehcal Computer S&ace 78 (1991) 377-381. Closure operations are considered as models of databases.  ...  Estimates on the number of closure operations on n elements (or equivalently, on the number of databases with n attributes) are given. 0304-3975/91/%03.50 @I l991-Elsevier Science Publishers B.V.  ...  * The work of these authors is supported by the Hunganan National Foundation for Scientific Research, grant number 1066.  ... 
doi:10.1016/0304-3975(91)90359-a fatcat:wkx6tgylnba7fozvsyunyg5vea

A Fuzzy Close Algorithm for Mining Fuzzy Association Rules [chapter]

Régis Pierrard, Jean-Philippe Poli, Céline Hudelot
2018 Communications in Computer and Information Science  
In this paper, we propose a fuzzy adaptation of the well-known Close algorithm which relies on the closure of itemsets.  ...  The Close-algorithm needs less passes over the dataset and is suitable when variables are correlated. The algorithm is then compared to other on public datasets.  ...  This new closure operator is based on a fuzzy closure operator of whom we take the kernel. The closure is the set of items that are shared by all the objects that include the generator.  ... 
doi:10.1007/978-3-319-91476-3_8 fatcat:t3qvmwhrofaq3d7njxrjqwco3m

Analysis of the US Food and Drug Administration Manufacturer and User Facility Device Experience database for adverse events involving Amplatzer septal occluder devices and comparison with the Society of Thoracic Surgery congenital cardiac surgery database

Daniel J. DiBardino, Doff B. McElhinney, Aditya K. Kaza, John E. Mayer
2009 Journal of Thoracic and Cardiovascular Surgery  
The purpose of this study is to use large databases to assess the frequency and severity of such complications and compare them with those of surgical atrial septal defect closure. From the  ...  The relative frequency and consequence of complications resulting from the attempted placement of such devices, however, have not been well assessed.  ...  The analysis of the predicted complication rate of the Amplatzer device hinges on this number.  ... 
doi:10.1016/j.jtcvs.2009.02.032 pmid:19464444 pmcid:PMC4230527 fatcat:ca2ipjvknne6rbr4dee4bapki4

Partial dependencies in relational databases and their realization

J. Demetrovics, G.O.H. Katona, D. Miklós
1992 Discrete Applied Mathematics  
On the other hand, we give necessary and sufficient conditions so that for such a closure operation one can find on the given set of attributes a database whose partial dependencies generate the given  ...  We show that the partial dependencies can be characterized by the closure operations of the poset formed by the partial functions on the attributes of the databases.  ...  On the other hand, we have to know that not all function closure operations defined on partial functions are closure operations given by the partial dependency structure of a certain database.  ... 
doi:10.1016/0166-218x(92)90026-7 fatcat:f3ky5da4xjewbbqoknqndob5ry

Octopus: A Reflective Language Mechanism for Object Manipulation [chapter]

Alex Farkas, Alan Dearle
1994 Database Programming Languages (DBPL-4)  
A class of database programs exist which are required to operate over an infinite number of types; included in this class are object browsers and query tools.  ...  An additional feature of this technique, as the name suggests, is the ability to isolate portions of closures, and copy them to other locations.  ...  Acknowledgments This work is supported in part by the Defence Science and Technology Organisation of Australia through their assistance in the PIPE project, and by the Australian Research Council.  ... 
doi:10.1007/978-1-4471-3564-7_4 fatcat:vfkbkxtfsjgt3dgfgmbdysw4je

SemEQUAL: Multilingual Semantic Matching in Relational Systems [chapter]

A. Kumaran, Jayant R. Haritsa
2005 Lecture Notes in Computer Science  
A performance evaluation of SemEQUAL, implemented using standard SQL:1999 features on a suite of commercial database systems indicates unacceptably slow response times.  ...  A pre-requisite for efficiently achieving this goal is that the underlying database engines must provide seamless matching of text data across languages.  ...  Bhattacharyya, Coordinator of Center for Indian Language Technology at IIT-Bombay, for providing us with details on Hindi WordNet.  ... 
doi:10.1007/11408079_20 fatcat:s4dfhap375g6zaq42j5dgr3hsi

An Efficient Algorithm for Enumerating Closed Patterns in Transaction Databases [chapter]

Takeaki Uno, Tatsuya Asai, Yuzo Uchida, Hiroki Arimura
2004 Lecture Notes in Computer Science  
for the number of frequent closed patterns.  ...  The class of closed patterns is a well known condensed representations of frequent patterns, and have recently attracted considerable interest.  ...  Acknowledgment We would like to thank Professor Ken Satoh of National Institute of Informatics and Professor Kazuhisa Makino of Osaka University for fruitful discussions and comments on this issue.  ... 
doi:10.1007/978-3-540-30214-8_2 fatcat:6md7ucjjdngkbae4ddwhtt7zrm

Supporting Ontology-based Semantic Matching in RDBMS [chapter]

S DAS, E CHONG, G EADON, J SRINIVASAN
2004 Proceedings 2004 VLDB Conference  
This paper presents the ontology-related functionality including inferencing, discusses how it is implemented on top of Oracle RDBMS, and illustrates the usage with several database applications.  ...  Our approach enables users to reference ontology data directly from SQL using the semantic match operators, thereby opening up possibilities of combining with other operations such as joins as well as  ...  Acknowledgments We thank Jay Banerjee for his comments on an earlier version of this paper.  ... 
doi:10.1016/b978-012088469-8/50092-9 fatcat:4aqbfiv3zrbgbpdfbhl2qts6ly

Supporting Ontology-based Semantic Matching in RDBMS [chapter]

Souripriya Das, Eugene Inseok Chong, George Eadon, Jagannathan Srinivasan
2004 Proceedings 2004 VLDB Conference  
This paper presents the ontology-related functionality including inferencing, discusses how it is implemented on top of Oracle RDBMS, and illustrates the usage with several database applications.  ...  Our approach enables users to reference ontology data directly from SQL using the semantic match operators, thereby opening up possibilities of combining with other operations such as joins as well as  ...  Acknowledgments We thank Jay Banerjee for his comments on an earlier version of this paper.  ... 
doi:10.1016/b978-012088469-8.50092-9 dblp:conf/vldb/DasCES04 fatcat:wvhbt7c6b5cz5bbwtwobj7iwiq

A life-long SLAM approach using adaptable local maps based on rasterized LIDAR images [article]

Waqas Ali, Peilin Liu, Rendong Ying, Zheng Gong
2021 arXiv   pre-print
We evaluate the performance of our system on the KITTI dataset and an indoor dataset. Our loop closure system reported recall and precision of above 90 percent.  ...  We also present an efficient approach of using the bag of visual words method for loop closure detection and relocalization.  ...  The culling of older maps does not affect the global operation because we perform the re-localization and loop closure detection based on frame query from the BOW database.  ... 
arXiv:2107.07133v1 fatcat:2rp5im4khzaw7i2eo47m6ociji

Deciding Termination of Query Evaluation in Transitive-Closure Logics for Constraint Databases [chapter]

Floris Geerts, Bart Kuijpers
2002 Lecture Notes in Computer Science  
We study extensions of first-order logic over the reals with different types of transitive-closure operators as query languages for constraint databases that can be described by Boolean combinations of  ...  However, we show that the termination of the transitive closure of a continuous function graph in the twodimensional plane is decidable, and even expressible in first-order logic over the reals.  ...  Transitive-closure logics We now define a number of extensions of FO (and of FO Lin ) with different types of transitiveclosure operators.  ... 
doi:10.1007/3-540-36285-1_13 fatcat:6bbrpopslzb2nlqr7yuxrrcrx4

Algebraic optimization of recursive queries

Maurice A.W. Houtsma, Peter M.G. Apers
1992 Data & Knowledge Engineering  
We also describe how to push selections into the resulting transitive closure operations.  ...  In this paper we describe an optimization strategy that rewrites regular (in the context of formal grammars) mutually recursive queries into standard Relational Algebra and transitive closure operations  ...  Acknowledgements We thank the reviewers for their comments, which have greatly improved the quality of the paper.  ... 
doi:10.1016/0169-023x(92)90029-b fatcat:tcydmhdf6zcgri3ty3dmhgmd5i

Peri-operative factors predisposing to pharyngocutaneous fistula after total laryngectomy: analysis of a large multi-institutional patient cohort

Nicole L. Lebo, Lisa Caulley, Hussain Alsaffar, Martin J. Corsten, Stephanie Johnson-Obaseki
2017 Journal of Otolaryngology - Head and Neck Surgery  
Methods: Retrospective cohort analysis was performed using patients undergoing total laryngectomy in the ACS-NSQIP database for 2006-2014. Sub-analysis was performed based on reconstruction type.  ...  Three variables showed statistical significance in predicting PCF: wound classification of 3 and 4 vs. 1-2 (OR 6.42 P < 0.0004 and OR 8.87, P < 0.0042), pre-operative transfusion of > 4 units of packed  ...  Availability of data and materials The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.  ... 
doi:10.1186/s40463-017-0233-z pmid:28830509 pmcid:PMC5568352 fatcat:ieo635fjq5hvhhr2yukrcme77u

On semantic matching of multilingual attributes in relational systems

A. Kumaran, Jayant R. Haritsa
2004 Proceedings of the Thirteenth ACM conference on Information and knowledge management - CIKM '04  
Then, TH(S c out i ) denotes the transitive closure of S c out i in one of the output languages Lout i and¨i TH(S c out i ) denotes the union of all such closures.  ...  Our experiments on a commercial database systems underscored the inefficiency of the SemEQUAL operator, in computing transitive closure, an essential component for semantic matching.  ... 
doi:10.1145/1031171.1031217 dblp:conf/cikm/KumaranH04 fatcat:qlw5tp2dxbfivglcmu5z4otbc4

Discussion

2009 Journal of Thoracic and Cardiovascular Surgery  
The analysis of the predicted complication rate of the Amplatzer device hinges on this number.  ...  Just over one year, we studied the Amplatzer ASD closure. In the last year, our cardiologists have done 94 Amplatzer ASD closures and defend the first-year closure on 10 patients.  ... 
doi:10.1016/j.jtcvs.2009.02.048 fatcat:4mtez3zx7ncc7gy5n7se2z7a5y
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