Nikitas A. Alexandridis

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In this paper, we overview general hardware architecture and a programming model of SRC-6E reconfigurable computers, and compare the performance of the SRC-6E machine vs. Intel Pentium IV. SRC-6E execution time measurements have been performed using three different approaches. In the first approach, the entire end-to-end execution time is taken into(More)
Job Management Systems (JMSs) efficiently schedule and monitor jobs in parallel and distributed computing environments. Therefore, they are critical for improving the utilization of expensive resources in high-performance computing systems and centers, and an important component of grid software infrastructure. With many JMSs available commercially and in(More)
The explosive increase in the amounts of image (and multimedia) data being generated, processed, and used in several computer applications have necessitated the development of image (and multimedia) database systems with newer features such as content-based indices and similarity searches. This paper presents a scheme for contentbased retrievals in image(More)
Summary form only given. Reconfigurable computers (RCs) can leverage the synergism between conventional processors and FPGAs to provide low-level hardware functionality at the same level of programmability as general-purpose computers. In a large class of applications, the total I/O time is comparable or even greater than the computations time. As a result,(More)
One important component of grid software infrastructure and parallel systems management is the Job Management System (JMS). With many JMSs available commercially and in public domain, it is difficult to choose the most efficient JMS for a given computing environment. All previous comparisons of JMSs had only a conceptual character. In this paper, we present(More)
In this paper, two quad-tree (QT) baseddynamic processor allocation/deallocation heuristic algorithms are proposed for a partitionable Mesh-connected parallel multicomputer: the QTTL (Quad Tree Top Left) and the QTR (Quad Tree Root) partition first heuristics. For each QT-based algorithm, a theoretical analysis of its computational time complexity is(More)
Recently, the researchers mostly are interested in only the search for the data content that are globally similar to the query, not the search inside data items. This paper presents an ) (logn O algorithm, called “generalized virtual node (GVN)” algorithm, to search data where parts of them have the same contents as of the query. Each multimedia datatype is(More)
Distributed reconfigurable resources, such as FPGA-based accelerator boards1 are expensive and often underutilized. Therefore, it is important to permit sharing these resources at least among the members of the same organization. Traditional resources, such as CPU time of loosely coupled workstations can be shared using a variety of existing distributed(More)