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On the equivalent descriptions of family of functional dependencies in the relational data model

Vũ Đức Thi
2016 Journal of Computer Science and Cybernetics  
The family of functional dependencies (FDs) was introduced by E.F. Codd. Equivalent descriptions of family of FDs play essential rules in the design and implementation of the relation datamodel.  ...  We prove that this family is an equivalent description of family of FDs. The concept of nonredundant family of attributes is also introduced in this paper.  ...  It is known [9] th at we used the fam ily {(A, {a}) : A £ MAX{F+ ,a), a € R} in algorithm for generating A rm strong relations and inferring functional dependencies.  ... 
doi:10.15625/1813-9663/11/4/8159 fatcat:2v62za6qhnfxrhj4lagh37wnai

On a general class of data dependencies in the relational model and its implication problems

A. Benczúr, A. Kiss, T. Márkus
1991 Computers and Mathematics with Applications  
In the second part of the paper we deal with implication problems for EGD, TTGD, TGD types of dependencies of relational databases, wich are generalizations of dependencies, introduced by Beeri -Vardi  ...  The present paper deals with an important problem of the relational database theory, with analysis of dependencies.  ...  One of the families of constraints is the family of data dependencies (the class of first-order sentences of a specific syntax [8] ).  ... 
doi:10.1016/0898-1221(91)90226-t fatcat:pie4yi4lkfcanodqwwz6rhz72u

(2021) Volume 2, Issue 4 Cultural Implications of China Pakistan Economic Corridor (CPEC Authors: Dr. Unsa Jamshed Amar Jahangir Anbrin Khawaja Abstract: This study is an attempt to highlight the cultural implication of CPEC on Pak-China relations, how it will align two nations culturally, and what steps were taken by the governments of two states to bring the people closer. After the establishment of diplomatic relations between Pakistan and China, the cultural aspect of relations between the two states al ...

2021 Journal of Development and Social Sciences  
Inter-provincial water sharing issue in Pakistan is a classic example of upstream-downstream rivalry which has been traced back from the pre-partition history of Pakistan.  ...  Many international treaties, laws and water management models are available to settle down the water sharing issues among the states like Absolute Territorial Sovereignty and the Upper Riparian, Absolute  ...  It is obvious that sharing of water among provinces is slightly dependent on political pressure as well.  ... 
doi:10.47205/jdss.2021(2-iv)74 fatcat:o63evbbvmfghhfbrzetuczvedq

Leveraging D-Separation for Relational Data Sets

Matthew J.H. Rattigan, David Jensen
2010 2010 IEEE International Conference on Data Mining  
Prior work has demonstrated that conventional independence tests suffer from dramatically increased rates of Type I errors when naively applied to relational data.  ...  We use graphical models to specify the conditions under which these errors occur, and use those models to devise novel and accurate conditional independence tests.  ...  The views and conclusion contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the Air  ... 
doi:10.1109/icdm.2010.142 dblp:conf/icdm/RattiganJ10 fatcat:ft34vbhryjewro33ztelq5qprm

On Uncertain Probabilistic Data Modeling

Teng Lv, Ping Yan, Weimin He
2016 International Journal of Database Theory and Application  
The rest of the paper is organized as follows. Probabilistic models in relational databases are given in Section 2. XML probabilistic data models are given in Section 3.  ...  For example, node A maybe dependent on node B, edge e(A,B) maybe dependent on edge e(B,C), and attribute a 1 of node A maybe dependent on attribute a 2 of node A in an uncertain graph. Ref.  ... 
doi:10.14257/ijdta.2016.9.12.17 fatcat:p6kufmldwfhwrdeit3nntpxmsi

A Shrinkage Approach for Modeling Non-stationary Relational Autocorrelation

Pelin Angin, Jennifer Neville
2008 2008 Eighth IEEE International Conference on Data Mining  
This is primarily due to the presence of autocorrelation in relational datasets, meaning that the class labels of related entities are correlated and inferences about one instance can be used to improve  ...  In this paper, we examine two real-world datasets and show that there is significant variance in the autocorrelation dependencies throughout the relational data graphs.  ...  The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements either expressed or implied, of DARPA  ... 
doi:10.1109/icdm.2008.147 dblp:conf/icdm/AnginN08 fatcat:4xyp6wccszbkbaumtwvtb34t24

Why collective inference improves relational classification

David Jensen, Jennifer Neville, Brian Gallagher
2004 Proceedings of the 2004 ACM SIGKDD international conference on Knowledge discovery and data mining - KDD '04  
We investigate the underlying mechanisms for this error reduction by reviewing past work on collective inference and characterizing different types of statistical models used for making inference in relational  ...  Procedures for collective inference make simultaneous statistical judgments about the same variables for a set of related data instances.  ...  Relational 1 (R1) -The model R1 is a simple relational model indicating that the attributes of an object depend on the class label of that object as well as the class labels of objects one link away.  ... 
doi:10.1145/1014052.1014125 dblp:conf/kdd/JensenNG04 fatcat:ozpl72kzyfcfvjpbsxcywngium

An Approach for Normalizing Fuzzy Relational Databases Based on Join Dependency
English

Deepa S
2014 International Journal of Computer Trends and Technology  
Fuzziness in databases is used to denote uncertain or incomplete data. Relational Databases stress on the nature of the data to be certain.  ...  As join dependency implies an multivalued dependency by symmetry the proof of join dependency based normalization is stated from the perspective of multivalued dependency based normalization on fuzzy relational  ...  Join dependency on relational model Join dependency on relational model is a special case of multi valued dependency [5] . The same idea is extended to Fuzzy relational databases [2] .  ... 
doi:10.14445/22312803/ijctt-v9p101 fatcat:s7uxlcneqjabfcztjm5wrwhj3e

The entity-relationship model---toward a unified view of data

Peter Pin-Shan Chen
1976 ACM Transactions on Database Systems  
The model can achieve a high degree of data independence and is based on set theory and relation theory, The entity-relationship model can be used as a basis for a unified view of data.  ...  The relational model is based on relational theory and can achieve a high degree of data independence, but it may lose some important semantic information about the real world [12, 15, 231.  ...  In the relational model, "attribute" B of a relation is functionally dependent on "attribute" A of the same relation if each value of A has no more than one value of B associated with it in the relation  ... 
doi:10.1145/320434.320440 fatcat:tckuwvkwpzdhfoisqo6xyqo7pq

The Entity-Relationship Model—Toward a Unified View of Data [chapter]

PETER PIN-SHAN CHEN
1989 Readings in Artificial Intelligence and Databases  
The model can achieve a high degree of data independence and is based on set theory and relation theory, The entity-relationship model can be used as a basis for a unified view of data.  ...  The relational model is based on relational theory and can achieve a high degree of data independence, but it may lose some important semantic information about the real world [12, 15, 231.  ...  In the relational model, "attribute" B of a relation is functionally dependent on "attribute" A of the same relation if each value of A has no more than one value of B associated with it in the relation  ... 
doi:10.1016/b978-0-934613-53-8.50013-3 fatcat:vtn4srh3qbewnpoili6hspy5j4

The Entity Relationship Model — Toward a Unified View of Data [chapter]

Peter Pin-Shan Chen
2002 Software Pioneers  
The model can achieve a high degree of data independence and is based on set theory and relation theory, The entity-relationship model can be used as a basis for a unified view of data.  ...  The relational model is based on relational theory and can achieve a high degree of data independence, but it may lose some important semantic information about the real world [12, 15, 231.  ...  In the relational model, "attribute" B of a relation is functionally dependent on "attribute" A of the same relation if each value of A has no more than one value of B associated with it in the relation  ... 
doi:10.1007/978-3-642-59412-0_18 fatcat:mfwu5eaavre33knmmy4wv7w5vm

The Entity Relationship Model — Toward a Unified View of Data [chapter]

Peter Pin-Shan Chen
1976 Pioneers and Their Contributions to Software Engineering  
The model can achieve a high degree of data independence and is based on set theory and relation theory, The entity-relationship model can be used as a basis for a unified view of data.  ...  The relational model is based on relational theory and can achieve a high degree of data independence, but it may lose some important semantic information about the real world [12, 15, 231.  ...  In the relational model, "attribute" B of a relation is functionally dependent on "attribute" A of the same relation if each value of A has no more than one value of B associated with it in the relation  ... 
doi:10.1007/978-3-642-48354-7_7 fatcat:7ypo5iohafbsxj3gvaq4iwxorm

A Dependence Stability Bound based on the VC Dimension for Relational Classification

Xing Wang, Hui He, Bin-Xing Fang, Hong-Li Zhang
2015 International Journal of Database Theory and Application  
RC models do not have improved stability to smooth the perturbations generated by variations in the correlation between the relational data.  ...  Relational classification (RC) is concerned with the application of statistical learning to relational data.  ...  The authors also gratefully acknowledge the helpful comments and suggestions of the reviewers.  ... 
doi:10.14257/ijdta.2015.8.3.11 fatcat:tjonthkl7vdrbgknavwng5hkv4

Refactor Business Process Models with Maximized Parallelism

Tao Jin, Jianmin Wang, Yun Yang, Lijie Wen, Keqin Li
2016 IEEE Transactions on Services Computing  
More specifically, we analyze the real causal relations between business tasks based on data operation dependency analysis, and refactor business process models with process mining technology.  ...  In this paper, we propose a novel approach on how to systematically refactor business process models with parallel structures for sequence structures for the first time.  ...  model in Fig. 1 , after we compute the causal relations based on data operation dependency as shown in Example 11, we compute the transitive causal relations and the core causal relations based on data  ... 
doi:10.1109/tsc.2014.2383391 fatcat:yrw3p2r2gzc47fdxgsqqwo32gq

Synthesis of the Canonical Models for Database Integration Preserving Semantics of the Value Inventive Data Models [chapter]

Leonid Kalinichenko, Sergey Stupnikov
2012 Lecture Notes in Computer Science  
This paper considers such decidable classes of dependencies as the assets for creation of new data models (called in the paper the value inventive data models) analogously to axiomatic extension of the  ...  The paper 1 examines the decidable classes of dependencies reflecting the semantics of value inventive data models considering such classes to be the extensions of the canonical data model kernel.  ...  In course of this discussion it is assumed that the relational model is used as a kernel of the canonical data model and databases are considered as collections of relations on two distinct and disjoint  ... 
doi:10.1007/978-3-642-33074-2_17 fatcat:3ywixhd5mrdkfpfse4haqnm5xe
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