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In this paper, we propose a data stream management system embedded to a smart card for handling and storing user specific summaries of streaming data coming from medical sensor measurements and/or other medical measurements. The data... more
In this paper, we propose a data stream management system embedded to a smart card for handling and storing user specific summaries of streaming data coming from medical sensor measurements and/or other medical measurements. The data stream management system that we propose for a health card can handle the stream data rates of commonly known medical devices and sensors. It incorporates a type of context awareness feature that acts according to user specific information. The proposed system is cheap and provides security for private data by enhancing the capabilities of smart health cards. The stream data management system is tested on a real smart card using both synthetic and real data.
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A methodology for choosing pointer access structures for a relational database is proposed. The methodology is based on the usage patterns of the database that are represented as views. The pointer access structures can be simple access... more
A methodology for choosing pointer access structures for a relational database is proposed. The methodology is based on the usage patterns of the database that are represented as views. The pointer access structures can be simple access structures, such as circular chains, pointer indexes, chains, and tree indexes, as well as compound access structures, such as a tree index pointing to a set of pointer indexes.<<ETX>>
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Moving object databases (MOD) are being used in a wide range of location-based services that are of growing interest in many application areas. In the literature, several query types such as nearest neighbor, reverse nearest neighbor,... more
Moving object databases (MOD) are being used in a wide range of location-based services that are of growing interest in many application areas. In the literature, several query types such as nearest neighbor, reverse nearest neighbor, k-nearest neighbor, and proximity queries have been considered in MOD. In this paper, we propose a novel operator called the assignment operator as a query type for MOD. The assignment operator is an operator used in a query to solve the assignment problem (also known as the weighted bipartite graph-matching problem). Assignment operator finds a perfect match between two sets of objects in a manner that minimizes a total cost. For instance, a set of moving objects such as taxi cabs are assigned to a set of customers in a manner that minimizes the total cost of traveling for the taxis. A possible implementation of the assignment operator in MOD and its performance evaluation are given.
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Clustering the related tuples of a pair of relations that are in many-to-one relationship (We call it inter-clustering.) expedites equijoin and natural join operations on these base relations. However, inter-clustering slows down other... more
Clustering the related tuples of a pair of relations that are in many-to-one relationship (We call it inter-clustering.) expedites equijoin and natural join operations on these base relations. However, inter-clustering slows down other relational algebra operations. Thus it is important to determine globally the pairs of relations to inter-cluster. In this paper we present a methodology which first finds out the candidate pairs of relations to inter-cluster from database accesses. Then it determines an optimal schema consisting of pairs of relations to inter-cluster, using a global optimization algorithm based on a weighted graph matching solution. The objective of the optimization is minimizing the cost of processing the relational algebra operations on the base relations associated with the database accesses. The optimization algorithm gives an exact solution and is not a heuristic one. The whole methodology is of polynomial worst case time order complexity. The proof of correctness of the various steps...
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Abstract. Write-Once-Read-Many (WORM) storage devices may be used to store critical medical data to prevent them from easy modification. In this paper, we propose a novel indexing structure for encrypted medical XML documents stored in... more
Abstract. Write-Once-Read-Many (WORM) storage devices may be used to store critical medical data to prevent them from easy modification. In this paper, we propose a novel indexing structure for encrypted medical XML documents stored in WORM storage. The proposed indexing that uses Generalized Hash Tree (GHT) expedites projection and selection operations on encrypted medical XML records stored in WORM storage. We implemented and tested the proposed system.
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Abstract. Association rule mining is used in various applications. Also information systems may need to take privacy issues into account when releasing data to outside parties. Due to recent advances, releasing data to other parties may... more
Abstract. Association rule mining is used in various applications. Also information systems may need to take privacy issues into account when releasing data to outside parties. Due to recent advances, releasing data to other parties may be done in a streaming fashion. In this paper, we introduce a new system in which association rule mining over data streams and association rule hiding for traditional databases are merged. The stream association rule hiding algorithm presented can be applied on both raw data and template guided XML data. The algorithms presented are implemented and tested.
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Index selection for relational databases is an important issue which has been researched quite extensively [1–5]. In the literature, in index selection algorithms for relational databases, at most one index is considered as a candidate... more
Index selection for relational databases is an important issue which has been researched quite extensively [1–5]. In the literature, in index selection algorithms for relational databases, at most one index is considered as a candidate for each attribute of a relation. However, it is possible that more than one different type of indexes with different storage space requirements may be present as candidates for an attribute. Also, it may not be possible to eliminate locally all but one of the candidate indexes for an attribute due to different benefits and storage space requirements associated with the candidates. Thus, the algorithms available in the literature for optimal index selection may not be used when there are multiple candidates for each attribute and there is a need for a global optimization algorithm in which at most one index can be selected from a set of candidate indexes for an attribute. The problem of index selection in the presence of multiple candidate indexes for...
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Time information is an important aspect of a health information system. Health information cannot be represented and queried correctly without time in medical research, auditing, and medicolegal cases. Extensible Markup Language (XML) is... more
Time information is an important aspect of a health information system. Health information cannot be represented and queried correctly without time in medical research, auditing, and medicolegal cases. Extensible Markup Language (XML) is being used in health information systems and has been formerly proposed as a data model for anaesthesia information systems. In this paper, we propose incorporating time into an XML model for anaesthesia information systems. A new storage structure and a temporal index structure are proposed in order to store temporal XML data and process time queries efficiently. In our proposed model, time has 4 dimensions: valid time, transaction time, event time, and availability time. We discuss the advantages of attaching the time information to the data in anaesthesia records. We implemented and tested the proposed model and the storage structures.
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Incorporating indefinite information into databases has been studied extensively. In this paper, we propose a structure called an E-table to represent maybe information and inclusive and exclusive disjunctions. We define the type of... more
Incorporating indefinite information into databases has been studied extensively. In this paper, we propose a structure called an E-table to represent maybe information and inclusive and exclusive disjunctions. We define the type of redundancies in E-tables and show how to eliminate them. Also we present an extended relational algebra to operate on E-tables. In this paper we expand the concepts and operations defined by Lin and Sunderraman [1] in order to accommodate exclusive disjunctions in relational databases.
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In this paper, we propose a data stream management system embedded to a smart card for handling and storing user specific summaries of streaming data coming from medical sensor measurements and/or other medical measurements. The data... more
In this paper, we propose a data stream management system embedded to a smart card for handling and storing user specific summaries of streaming data coming from medical sensor measurements and/or other medical measurements. The data stream management system that we propose for a health card can handle the stream data rates of commonly known medical devices and sensors. It incorporates a type of context awareness feature that acts according to user specific information. The proposed system is cheap and provides security for private data by enhancing the capabilities of smart health cards. The stream data management system is tested on a real smart card using both synthetic and real data.