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On the Desirability of Acyclic Database Schemes

Catriel Beeri, Ronald Fagin, David Maier, Mihalis Yannakakis
1983 Journal of the ACM  
A class of database schemes, called acychc, was recently introduced. It is shown that this class has a number of desirable properties.  ...  In particular, several desirable properties that have been studied by other researchers m very different terms are all shown to be eqmvalent to acydicity.  ...  Thus the class of acyclic database schemes is a natural, important class, since it can be characterized in a number of ways, each corresponding to a desirable property of database schemes or to a natural  ... 
doi:10.1145/2402.322389 fatcat:fohuzs2gv5gztpewfyrbyshfy4

An Analysis of Characterized Plant Sesquiterpene Synthases [article]

Janani Durairaj, Alice Di Girolamo, Harro J Bouwmeester, Dick de Ridder, Jules Beekwilder, Aalt D.J. van Dijk
2018 bioRxiv   pre-print
The annotated enzyme sequences allowed for an analysis of terpene synthase motifs, leading to the extension of one motif and recognition of a variant of another.  ...  This demonstrates an application of our database in choosing likely-functional residues for mutagenesis studies aimed at understanding or changing sesquiterpene synthase product specificity.  ...  Acknowledgements This work is part of the research programme Novel Enzymes for Flavour and Fragrance with project number TTW 15043 which is financed by the Netherlands Organisation for Scientific Research  ... 
doi:10.1101/466839 fatcat:xqex256divh5xi3mxzdwngg5su

Recognizing different types of beta-cycles in a database scheme

To-Yat Cheung, Yunzhou Zhu
1991 Theoretical Computer Science  
An algorithm is then proposed for detecting their presence or absence in a database scheme. The database scheme is beta-acyclic if all of them are absent.  ...  For example, an aiphaacyclic database scheme satisfies such desirable properties [2,6] as equivale  ...  In database management, it is sometimes desirable to reco ize or to have the acyclicity properties in the subschemes of a database scheme.  ... 
doi:10.1016/0304-3975(91)90197-a fatcat:gq65kmb7ojehjghi5eughwnfau

Design of desirable relational database schemes

Li-Yan Yuan, Z.Meral Ozsoyoglu
1992 Journal of computer and system sciences (Print)  
We define extended conflict free dependencies in the context of functional and multivalued dependencies and prove that there exists an acyclic, dependency preserving, 4NF database scheme if and only if  ...  The result is also applicable when the data dependencies consists of only functional dependencies, giving the necessary and sufftcient condition for an acyclic, dependency preserving BCNF database scheme  ...  ACKNOWLEDGMENTS We are grateful to anonymous referees who reviewed an earlier version of this paper and made many constructive comments.  ... 
doi:10.1016/0022-0000(92)90034-g fatcat:fum2wjjwwfebrcztyqjstnbq6a

Mining Approximate Acyclic Schemes from Relations [article]

Batya Kenig, Pranay Mundra, Guna Prasad, Babak Salimi, Dan Suciu
2019 arXiv   pre-print
Multivalued dependencies (MVDs) are the building blocks of acyclic schemes.  ...  Acyclic schemes have numerous applications in databases and in machine learning, such as improved design, more efficient storage, and increased performance for queries and machine learning algorithms.  ...  We prove the claim by backwards induction on the lexicographic ordering of the subsets of Ω.  ... 
arXiv:1911.12933v1 fatcat:bmuzsmig35dm5e34sxznwojo4m

A representation and classification scheme for tree-like structures in medical images: an application on branching pattern analysis of ductal trees in x-ray galactograms

Vasileios Megalooikonomou, Despina Kontos, Joseph Danglemaier, Ailar Javadi, Predrag R. Bakic, Andrew D. A. Maidment, Joseph M. Reinhardt, Josien P. W. Pluim
2006 Medical Imaging 2006: Image Processing  
Developing such automated tools for the analysis of tree-like structures in medical images can potentially provide insight to the relationship between the topology of branching and function or pathology  ...  / on 07/15/2016 Terms of Use: Proc. of SPIE Vol. 6144 61441H-7 Downloaded From: on 07/15/2016 Terms of Use:  ...  /Radiological Society of North America Research Seed Grant SD0329, and by National Cancer Institute Program Project Grant PO1 CA85484.  ... 
doi:10.1117/12.651426 dblp:conf/miip/Megalooikonomou06 fatcat:hg4uz3aofjdxdb6r5movm5gzcq

Independent database schemes under functional and inclusion dependencies

Paolo Atzeni, Edward P. F. Chan
1991 Acta Informatica  
In a context considering in a unique framework all the relations in a database, by means of the notion of global consistency, independent database schemes allow enforcement of constraints to be performed  ...  Independent schemes have hitherto been studied in the presence of functionirl and join dependencies.  ...  Kanellakis for providing them with an advance copy of the full version of 113). References  ... 
doi:10.1007/bf01261656 fatcat:2ybjs6fzwzdlrdmgvrfrbmmb4q

Multi-version concurrency control scheme for a database system

Shojiro Muro, Tiko Kameda, Toshimi Minoura
1984 Journal of computer and system sciences (Print)  
A concurrency control scheme using multiple versions of data objects is presented which allows increased concurrency. The scheme grants an appropriate version to each read request.  ...  The scheduler outputs only (multi-version) wwserializable histories which preserve database consistency. It is shown that any "Dserializable" history of Papadimitriou (J. Assoc. Comput.  ...  By restoring a source to an acyclic graph we obtain another acyclic graph.  ... 
doi:10.1016/0022-0000(84)90031-x fatcat:ugmup6mvmrcptp6dhfouszo5si

Annotation Enrichment Analysis: An Alternative Method for Evaluating the Functional Properties of Gene Sets [article]

Kimberly Glass, Michelle Girvan
2013 arXiv   pre-print
Gene annotation databases (compendiums maintained by the scientific community that describe the biological functions performed by individual genes) are commonly used to evaluate the functional properties  ...  We find FET is strongly biased toward over-estimating overlap significance if a gene set has an unusually high number of annotations.  ...  RESULTS Annotation Properties Influence the Results of Functional Enrichment Analysis We wished to determine the effect of annotation properties on functional enrichment analysis.  ... 
arXiv:1208.4127v2 fatcat:x4btphdqivfxxgybbfo4z74nsm

A dynamic indexing scheme for multidimensional data

Manuk G Manukyan, Grigor R Gevorgyan
2018 Sovremennye Informacionnye Tehnologii i IT-obrazovanie  
This comparison shows effectiveness of suggested metadata storage environment. An estimation of directory size is presented.  ...  A prototype to support of our grid file concept has been created and experimentally compared with MongoDB (a renowned NoSQL database).  ...  More detailed analysis of big data systems can be found in [18] .  ... 
doi:10.25559/sitito.14.201801.111-125 fatcat:wyqzvmtd2ndcbfkvagagoweqn4

Towards Automated Reasoning on ORM Schemes [chapter]

Mustafa Jarrar
2007 Lecture Notes in Computer Science  
such as the modeling of business rules, XML-Schemes, data warehouses, requirements engineering,web forms, etc 1 .  ...  This would enable automated reasoning on the formal properties of ORM diagrams, such as detecting constraint contradictions and implications.  ...  "Because of their recursive nature, acyclic constraints maybe expensive or even impossible to enforce in some database systems." [8] .  ... 
doi:10.1007/978-3-540-75563-0_14 fatcat:btp6wqcz2fgmfh7j3fe3r7d5oa

The schematic protection model: its definition and analysis for acyclic attenuating schemes

Ravinderpal Singh Sandhu
1988 Journal of the ACM  
It also raises an analysis problem of characterizing the protection states derivable from a given initial state. A protection model provides a framework for both design and analysis.  ...  A preliminary version of this paper, for the special case of the schematic protection model called SSR, "Analysis of acyclic attenuating systems for the SSR protection model," appears in the  ...  We find it useful to view an authorization scheme as analogous to a database schema and the distribution of tickets as analogous to an extensional database.  ... 
doi:10.1145/42282.42286 fatcat:7x2lktnbfvgudmmuhb76p46mei

An integrated approach to logical design of relational database schemes

Catriel Beeri, Michael Kifer
1986 ACM Transactions on Database Systems  
We propose a new approach to the design of relational database schemes.  ...  We also assume that the reader is familiar with acyclic database schemes [6, 161. For the MVD-set (X -Vi)i = 1, . . . . n) we shall often write X +-+ S, where S = ] VT) i = 1, , n}.  ...  Then extend the scheme to an acyclic one. Decompose the scheme using only MVDs (or, equivalently, using the single JD).  ... 
doi:10.1145/5922.214291 fatcat:ip5pwjorjzc7bcealjziharrle

Generating the fewest redundancy-free scheme trees from acyclic conceptual-model hypergraphs in polynomial time

Wai Yin Mok, Joseph Fong, David W. Embley
2014 Information Systems  
We show, however, that the problem has a polynomial-time solution if the conceptual-model hypergraph is acyclic.  ...  As a practical application for the algorithm, we comment on its use for the design of "good" XML schemas for data storage.  ...  Acknowledgements The work described in this paper was partially supported by Strategic Research Grants 7001945 and 7002140 of City University of Hong Kong. D.W.  ... 
doi:10.1016/ fatcat:wqjnqmbarrf6hewu4iz465nrxe

Soft Schemes for Earthquake-Geotechnical Dilemmas

Silvia García
2013 International Journal of Geophysics  
Since the quality of the model typically determines an upper bound on the quality of the final problem solution, modeling is often the bottleneck in the development of the whole system.  ...  Models make it possible to predict or simulate a system's behavior; in earthquake geotechnical engineering, they are required for the design of new constructions and for the analysis of those that exist  ...  The resulting classification tree is a connected acyclic graph with remarkable advantages over regression, discriminant analysis, and other procedures based on algebraic models.  ... 
doi:10.1155/2013/986202 fatcat:n42jtkk3arbg3izeainie3n4p4
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