introduction: direct and rapid access to information is one of the main necessities of the users in new technological world. nowadays, information users, particularly medical information in which rapid access is of necessity, do not have enough time to search and access to information. therefore, the present study aimed to determine strategies to access required information as soon as possible....

In a wireless client-server environment, data broadcasting is an efficient data dissemination method and some of the broadcast data are often cached at each mobile client’s cache. Data broadcasting and caching save communication bandwidth, resource usage, and data access time. A server also broadcasts invalidation reports (IRs) to maintain the consistency between server data and clients’ cached...

Object correlations are common semantic patterns in virtual reality systems. They can be exploited for improving the effectiveness of storage caching, prefecthing, data layout, and minimization of queryresponse times. Unfortunately, this information about object correlations is unavailable at the storage system level. Previous approaches for reducing I/O access time are seldom investigated. On ...

In this paper, we propose the DN-tree that is a data structure to build lossy summaries of the frequent data access patterns of the queries in a distributed graph data management system. These compact representations allow us an efficient communication of the data structure in distributed systems. We exploit this data structure with a new Dynamic Data Partitioning strategy (DYDAP) that assigns ...

In this paper we propose algorithms for generation of frequent itemsets by successive construction of the nodes of a lexicographic tree of itemsets. We discuss di erent strategies in generation and traversal of the lexicographic tree such as breadthrst search, depthrst search or a combination of the two. These techniques provide di erent trade-o s in terms of the I/O, memory and computational t...