data grids support access to widely distributed storage for large numbers of users accessing potentially many files. to enhance access time, replication at nearby sites may be used. data replication, a technique much investigated bydata grid researchers in past years creates multiple replicas offile and places them in conventional locations to shorten fileaccess times. one of the problems in da...

Modern information dissemination services can dynamically produce real-time data that is valid and useful depending on users’ on-demand data requests. Information servers must adopt a scheduling approach to maintain timely data access and system performance. Most previous studies on scheduling such data discuss on-demand data broadcasting and real-time task processing with various performance m...

Due to more and more customers keen on mobile services, we may face the mobile network congestion problem. Therefore, it is necessary to develop new data retrieval method to provide users with reliable and timely access to the data scourers. In this paper, we study the scheduling problem for retrieving data from multi-channel data broadcast environments. In general conditions, the most importan...

conclusions according to the results, there was a direct correlation between access to physical space in ed and waiting time. in addition, improving the physical access did not necessarily result in shorter waiting time. therefore, to improve triage process, improvement of waiting time indices, and modifying forms of work process in ed are recommended. results the correlation between the waitin...

in recent years, many researchers have been done in the area of wireless sensornetworks that has led to the variety of algorithms and methods for the collection andtransmission of environment information; but still many challenges faced bywireless sensor networks using methodologies are applied in various fields. such asmedia access control that due to the media being shared on these networks, ...

With the proliferation of wireless information applications and services, data broadcasting known from radio networks has become an important mechanism for mobile data access in wireless communication networks. Two data delivery techniques, push and pull, and their hybrid combination had been introduced to satisfy mobile user demands. However, most previous research efforts were elaborated upon...

Wavelet decomposition is a well-known technique to compress image data. Here, we have used wavelet decomposition to compress digital elevation models, DEM. The objectives for compressing DEMs are obtaining manageable and small data sets, and reducing data access time. In the paper, different aspects of wavelets as a base for data compression are described. The (de-)compression scheme consists o...

Replication methods can be used for shortening the data access time in Grid environment with heterogeneous storage resources. In this paper we describe the algorithms for automatic replication implemented by us in two grid projects having different requirements concerning data storage.