To solve the problems of shaving and reusing information in the information system, a rules-based ontology constructing approach from object-relational databases is proposed. A 3-tuple ontology constructing model is p...To solve the problems of shaving and reusing information in the information system, a rules-based ontology constructing approach from object-relational databases is proposed. A 3-tuple ontology constructing model is proposed first. Then, four types of ontology constructing rules including class, property, property characteristics, and property restrictions ave formalized according to the model. Experiment results described in Web ontology language prove that our proposed approach is feasible for applying in the semantic objects project of semantic computing laboratory in UC Irvine. Our approach reduces about twenty percent constructing time compared with the ontology construction from relational databases.展开更多
The constraints and the operations play an important role in database generalization.They guide and govern database generalization.The constraints are translation of the required conditions that should take into accou...The constraints and the operations play an important role in database generalization.They guide and govern database generalization.The constraints are translation of the required conditions that should take into account not only the objects and relationships among objects but also spatial data schema (classification and aggregation hierarchy) associated with the final existing database.The operations perform the actions of generalization in support of data reduction in the database.The constraints in database generalization are still lack of research.There is still the lack of frameworks to express the constraints and the operations on the basis of object_oriented data structure in database generalization.This paper focuses on the frameworks for generalization operations and constraints on the basis of object_oriented data structure in database generalization.The constraints as the attributes of the object and the operations as the methods of the object can be encapsulated in classes.They have the inheritance and polymorphism property.So the framework of the constraints and the operations which are based on object_oriented data structure can be easily understood and implemented.The constraint and the operations based on object_oriented database are proposed based on object_oriented database.The frameworks for generalization operations,constraints and relations among objects based on object_oriented data structure in database generalization are designed.The categorical database generalization is concentrated on in this paper.展开更多
This paper compares the differences between the mathematical model in graph theory and GIS network analysis model.Thus it claims that the GIS network analysis model needs to solve.Then this paper introduces the spatia...This paper compares the differences between the mathematical model in graph theory and GIS network analysis model.Thus it claims that the GIS network analysis model needs to solve.Then this paper introduces the spatial data management methods in object-relation database for GIS and discusses its effects on the network analysis model.Finally it puts forward the GIS network analysis model based on the object-relation database.The structure of the model is introduced in detail and research is done to the internal and external memory data structure of the model.The results show that it performs well in practice.展开更多
Aiming at the problem that current geographical information systems(GIS)usually does not maintain semantic and user-defined constraints out of three consistency-constrains(third refers to topology constraint),this res...Aiming at the problem that current geographical information systems(GIS)usually does not maintain semantic and user-defined constraints out of three consistency-constrains(third refers to topology constraint),this research focuses on building an efficient spatial data management system using two constraint violation detection methods.An algorithm for constraint violation detection has been derived to maintain the error-free up-to-date spatial database.Results indicate that the developed constraint violation detection(CVD)system is more efficient compared with conventional systems.展开更多
This paper presents a methodology driven by database constraints for designing and developing(database)software applications.Much needed and with excellent results,this paradigm guarantees the highest possible quality...This paper presents a methodology driven by database constraints for designing and developing(database)software applications.Much needed and with excellent results,this paradigm guarantees the highest possible quality of the managed data.The proposed methodology is illustrated with an easy to understand,yet complex medium-sized genealogy software application driven by more than 200 database constraints,which fully meets such expectations.展开更多
MatBase is a prototype data and knowledge base management expert intelligent system based on the Relational,Entity-Relationship,and(Elementary)Mathematical Data Models.Dyadic relationships are quite common in data mod...MatBase is a prototype data and knowledge base management expert intelligent system based on the Relational,Entity-Relationship,and(Elementary)Mathematical Data Models.Dyadic relationships are quite common in data modeling.Besides their relational-type constraints,they often exhibit mathematical properties that are not covered by the Relational Data Model.This paper presents and discusses the MatBase algorithm that assists database designers in discovering all non-relational constraints associated to them,as well as its algorithm for enforcing them,thus providing a significantly higher degree of data quality.展开更多
Homogeneous binary function products are frequently encountered in the sub-universes modeled by databases,spanning from genealogical trees and sports to education and healthcare,etc.Their properties must be discovered...Homogeneous binary function products are frequently encountered in the sub-universes modeled by databases,spanning from genealogical trees and sports to education and healthcare,etc.Their properties must be discovered and enforced by the software applications managing such data to guarantee plausibility.The(Elementary)Mathematical Data Model provides 17 types of dyadic-based homogeneous binary function product constraint categories.MatBase,an intelligent data and knowledge base management system prototype,allows database designers to simply declare them by only clicking corresponding checkboxes and automatically generates code for enforcing them.This paper describes the algorithms that MatBase uses for enforcing all 17 types of homogeneous binary function product constraint,which may also be employed by developers without access to MatBase.展开更多
Most of the previous studies concerning checking the integrity constraints in distributed database derive simplified forms of the initial integrity constraints with the sufficiency property, since the sufficient test ...Most of the previous studies concerning checking the integrity constraints in distributed database derive simplified forms of the initial integrity constraints with the sufficiency property, since the sufficient test is known to be cheaper than the complete test and its initial integrity constraint as it involves less data to be transferred across the network and can always be evaluated at the target site （single site）. Their studies are limited as they depend strictly on the assumption that an update operation will be executed at a site where the relation specified in the update operation is located, which is not always true. Hence, the sufficient test, which is proven to be local test by previous study, is no longer appropriate. This paper proposes an approach to checking integrity constraints in a distributed database by utilizing as much as possible the local information stored at the target site. The proposed approach derives support tests as an alternative to the existing complete and sufficient tests proposed by previous researchers with the intention to increase the number of local checking regardless the location of the submitted update operation. Several analyses have been performed to evaluate the proposed approach, and the results show that support tests can benefit the distributed database, where local constraint checking can be achieved.展开更多
Interval index structure plays an important role in constraint database systems. A dynamic interval index structure DM-tree is presented in this paper. The advantage of the DM-tree compared with other interval index ...Interval index structure plays an important role in constraint database systems. A dynamic interval index structure DM-tree is presented in this paper. The advantage of the DM-tree compared with other interval index structures is that the dynamic operations of insertion and deletion can be operated on the new structure. The storage complexity of the tree is O(n), and the query I/O complexity is O(log n+t/B). To improve the performance of the inserting and deleting operations, some methods such as neighbored-constraint and update-late are applied. The I / O complexity of inserting and deleting operations is the same as that in B-tree, i.e., O(log n).展开更多
We extend the constraint data model to allow complex objects and study the expressive power of various query languages over this sort of constraint databases.The tools we use come in the form of collapse results which...We extend the constraint data model to allow complex objects and study the expressive power of various query languages over this sort of constraint databases.The tools we use come in the form of collapse results which are well established in the context of first-order logic.We show that the natural-active collapse with a condition and the activegeneric collapse carry over to the second-order logic for structures with o-minimality property and any signature in the complex value relations.The expressiveness results for more powerful logics including monadic second-order logic,monadic second-order logic with fix-point operators,and fragments of second-order logic are investigated in the paper.We discuss the data complexity for second-order logics over constraint databases.The main results are that the complexity upper bounds for three theories,MSO+(LIN),MSO+(POLY),and Inflationary DATALOGact^cv(SC,M)without powerset operator are∪iΣi^NC1,NCH=∪iΣi^NC,and AC^0/poly,respectively.We also consider the problem of query closure property in the context of embedded finite models and constraint databases with complex objects and the issue of how to determine safe constraint queries.展开更多
Integrity constraint is a formula that checks whether all necessary information has been explicitly provided.It can be added into ontology to guarantee the data-centric application.In this paper,a set of constraint ax...Integrity constraint is a formula that checks whether all necessary information has been explicitly provided.It can be added into ontology to guarantee the data-centric application.In this paper,a set of constraint axioms called IC-mapping axioms are stated.Based on these axioms,a special ontology with integrity constraint,which is adapted to map ontology knowledge to data in relational databases,is defined.It's generated through our checking and modification.Making use of the traditional mapping approaches,it can be mapped to relational databases as a normal ontology.Unlike what in the past,a novel mapping approach named IC-based mapping is proposed in accordance with such special ontology.The detailed algorithm is put forward and compared with other existing approaches used in Semantic Web applications.The result shows that our method is advanced to the traditional approaches.展开更多
基金supported by the National Natural Science Foundation of China (60471055)the National "863" High Technology Research and Development Program of China (2007AA01Z443)
文摘To solve the problems of shaving and reusing information in the information system, a rules-based ontology constructing approach from object-relational databases is proposed. A 3-tuple ontology constructing model is proposed first. Then, four types of ontology constructing rules including class, property, property characteristics, and property restrictions ave formalized according to the model. Experiment results described in Web ontology language prove that our proposed approach is feasible for applying in the semantic objects project of semantic computing laboratory in UC Irvine. Our approach reduces about twenty percent constructing time compared with the ontology construction from relational databases.
文摘The constraints and the operations play an important role in database generalization.They guide and govern database generalization.The constraints are translation of the required conditions that should take into account not only the objects and relationships among objects but also spatial data schema (classification and aggregation hierarchy) associated with the final existing database.The operations perform the actions of generalization in support of data reduction in the database.The constraints in database generalization are still lack of research.There is still the lack of frameworks to express the constraints and the operations on the basis of object_oriented data structure in database generalization.This paper focuses on the frameworks for generalization operations and constraints on the basis of object_oriented data structure in database generalization.The constraints as the attributes of the object and the operations as the methods of the object can be encapsulated in classes.They have the inheritance and polymorphism property.So the framework of the constraints and the operations which are based on object_oriented data structure can be easily understood and implemented.The constraint and the operations based on object_oriented database are proposed based on object_oriented database.The frameworks for generalization operations,constraints and relations among objects based on object_oriented data structure in database generalization are designed.The categorical database generalization is concentrated on in this paper.
基金Funded by the National 973 Project(NO.G2000077904)the National 863 Project(No.2002AA131030).
文摘This paper compares the differences between the mathematical model in graph theory and GIS network analysis model.Thus it claims that the GIS network analysis model needs to solve.Then this paper introduces the spatial data management methods in object-relation database for GIS and discusses its effects on the network analysis model.Finally it puts forward the GIS network analysis model based on the object-relation database.The structure of the model is introduced in detail and research is done to the internal and external memory data structure of the model.The results show that it performs well in practice.
文摘Aiming at the problem that current geographical information systems(GIS)usually does not maintain semantic and user-defined constraints out of three consistency-constrains(third refers to topology constraint),this research focuses on building an efficient spatial data management system using two constraint violation detection methods.An algorithm for constraint violation detection has been derived to maintain the error-free up-to-date spatial database.Results indicate that the developed constraint violation detection(CVD)system is more efficient compared with conventional systems.
文摘This paper presents a methodology driven by database constraints for designing and developing(database)software applications.Much needed and with excellent results,this paradigm guarantees the highest possible quality of the managed data.The proposed methodology is illustrated with an easy to understand,yet complex medium-sized genealogy software application driven by more than 200 database constraints,which fully meets such expectations.
文摘MatBase is a prototype data and knowledge base management expert intelligent system based on the Relational,Entity-Relationship,and(Elementary)Mathematical Data Models.Dyadic relationships are quite common in data modeling.Besides their relational-type constraints,they often exhibit mathematical properties that are not covered by the Relational Data Model.This paper presents and discusses the MatBase algorithm that assists database designers in discovering all non-relational constraints associated to them,as well as its algorithm for enforcing them,thus providing a significantly higher degree of data quality.
文摘Homogeneous binary function products are frequently encountered in the sub-universes modeled by databases,spanning from genealogical trees and sports to education and healthcare,etc.Their properties must be discovered and enforced by the software applications managing such data to guarantee plausibility.The(Elementary)Mathematical Data Model provides 17 types of dyadic-based homogeneous binary function product constraint categories.MatBase,an intelligent data and knowledge base management system prototype,allows database designers to simply declare them by only clicking corresponding checkboxes and automatically generates code for enforcing them.This paper describes the algorithms that MatBase uses for enforcing all 17 types of homogeneous binary function product constraint,which may also be employed by developers without access to MatBase.
文摘Most of the previous studies concerning checking the integrity constraints in distributed database derive simplified forms of the initial integrity constraints with the sufficiency property, since the sufficient test is known to be cheaper than the complete test and its initial integrity constraint as it involves less data to be transferred across the network and can always be evaluated at the target site （single site）. Their studies are limited as they depend strictly on the assumption that an update operation will be executed at a site where the relation specified in the update operation is located, which is not always true. Hence, the sufficient test, which is proven to be local test by previous study, is no longer appropriate. This paper proposes an approach to checking integrity constraints in a distributed database by utilizing as much as possible the local information stored at the target site. The proposed approach derives support tests as an alternative to the existing complete and sufficient tests proposed by previous researchers with the intention to increase the number of local checking regardless the location of the submitted update operation. Several analyses have been performed to evaluate the proposed approach, and the results show that support tests can benefit the distributed database, where local constraint checking can be achieved.
基金Supported by the National Natural Science Foundation of China under grant !Nos.69933010 and69773012.
文摘Interval index structure plays an important role in constraint database systems. A dynamic interval index structure DM-tree is presented in this paper. The advantage of the DM-tree compared with other interval index structures is that the dynamic operations of insertion and deletion can be operated on the new structure. The storage complexity of the tree is O(n), and the query I/O complexity is O(log n+t/B). To improve the performance of the inserting and deleting operations, some methods such as neighbored-constraint and update-late are applied. The I / O complexity of inserting and deleting operations is the same as that in B-tree, i.e., O(log n).
文摘We extend the constraint data model to allow complex objects and study the expressive power of various query languages over this sort of constraint databases.The tools we use come in the form of collapse results which are well established in the context of first-order logic.We show that the natural-active collapse with a condition and the activegeneric collapse carry over to the second-order logic for structures with o-minimality property and any signature in the complex value relations.The expressiveness results for more powerful logics including monadic second-order logic,monadic second-order logic with fix-point operators,and fragments of second-order logic are investigated in the paper.We discuss the data complexity for second-order logics over constraint databases.The main results are that the complexity upper bounds for three theories,MSO+(LIN),MSO+(POLY),and Inflationary DATALOGact^cv(SC,M)without powerset operator are∪iΣi^NC1,NCH=∪iΣi^NC,and AC^0/poly,respectively.We also consider the problem of query closure property in the context of embedded finite models and constraint databases with complex objects and the issue of how to determine safe constraint queries.
基金supported by the National Natural Science Foundation of China(60973089,60873148)the Jilin Province Science and Technology Development Plan(20101501,20100185)+1 种基金the Erasmus Mundus External Cooperation Window’s Project(EMECW):Bridging the Gap(155776-EM-1-2009-1-IT-ERAMUNDUS-ECW-L12)the Foundation of Key Laboratory of SCKE of Ministry of Education(450060326019)
文摘Integrity constraint is a formula that checks whether all necessary information has been explicitly provided.It can be added into ontology to guarantee the data-centric application.In this paper,a set of constraint axioms called IC-mapping axioms are stated.Based on these axioms,a special ontology with integrity constraint,which is adapted to map ontology knowledge to data in relational databases,is defined.It's generated through our checking and modification.Making use of the traditional mapping approaches,it can be mapped to relational databases as a normal ontology.Unlike what in the past,a novel mapping approach named IC-based mapping is proposed in accordance with such special ontology.The detailed algorithm is put forward and compared with other existing approaches used in Semantic Web applications.The result shows that our method is advanced to the traditional approaches.
