The solution of tridiagonal systems is a topic of great interest in many areas of numerical analysis. Several algorithms have recently been proposed for solving triadiagonal systems based on the Divide and Conquer (DC) strategy. In this work we propose an unified parallel architecture for DC algorithms which present the data flows of the Successive Doubling, Recursive Doubling and Parallel Cycl...

In this paper, a parallel symmetric eigensolver with very small matrices in massively parallel processing is considered. We define very small matrices that fit the sizes of caches per node in a supercomputer. We assume that the sizes also fit the exa-scale computing requirements of current production runs of an application. To minimize communication time, we added several communication avoiding...

In latent semantic indexing, the addition of documents (or the addition of terms) to some already processed text collection leads to the updating of the best rank-k approximation of the term-document matrix. The computationally most intensive task in this updating is the computation of the singular value decomposition (SVD) of certain square matrix, which is upper or lower triangular, and conta...

Pressure ulcers are generally associated with external pressures exceeding internal capillary pressures over bony prominences when the body cannot initiate motor movement to change positions. This investigation evaluated microstructural changes occurring in human skin, in vitro, exposed to static versus cyclic pressures, simulating those recorded for heels of human subjects on various pressure-...

The standard Transmission Control Protocol (TCP) is based on an additive rate increase in absence of congestion, and on multiplicative decrease triggered by congestion signals. However, it does not scale well as the distances, or as the speed of the network, increase. Thus, we study some of the solutions that have been proposed to encounter this problem. These solutions include (i) splitting th...

The paper discusses the main aspects of a parallel debugger for the parallel object-oriented language pSather. PSather provides for a single shared-address space and for multiple threads per processor. Threads can arbitrarily migrate between processors. The debugger supports cyclic debugging which is a standard and quite effective technique for sequential programs. To address nondeterminism, de...

We study the cycles generated by the chip firing game associated with n-cube orientations. We consider a particular class of partitions of vertices of n-cubes called left cyclic partitions that induce parallel periodic evolutions. Using this combinatorical model, we show that cycles generated by parallel evolutions are of even lengths from 2 to 2 on Hn (n ≥ 1), and of odd lengths different from...

We present a parallel version of Viterbi’s decoding procedure, for which we are able to demonstrate that the resultant task graph has restricted complexity in that the number of communications to or from any processor cannot exceed 4 for BCH codes. The resulting algorithm works in lock step making it suitable for implementation on a systolic processor array, which we have implemented on a field...

We address the problem of scheduling a set of generic tasks to be performed in nitely often without preemption on nitely many parallel processors. These tasks are subject to a set of uniform constraints, modeled by a uniform graph G. The problem is to nd a periodic schedule that minimizes the cycle time. Although the problem is NPhard, we show that the special case where G is a circuit can be s...