Journal ArticleDOI
The power of parallel prefix
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This study assumes the weakest PRAM model, where shared memory locations can only be exclusively read or written (the EREW model) to solve the prefix computation problem, when the order of the elements is specified by a linked list.Abstract:
The prefix computation problem is to compute all n initial products a1* . . . *a1,i=1, . . ., n of a set of n elements, where * is an associative operation. An O(((logn) log(2n/p))XI(n/p)) time deterministic parallel algorithm using p≤n processors is presented to solve the prefix computation problem, when the order of the elements is specified by a linked list. For p≤O(n1-e)(e〉0 any constant), this algorithm achieves linear speedup. Such optimal speedup was previously achieved only by probabilistic algorithms. This study assumes the weakest PRAM model, where shared memory locations can only be exclusively read or written (the EREW model).read more
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Optimal parallel time bounds for the maximum clique problem on intervals
TL;DR: Two optimal parallel time bounds are derived for the maximum clique problem on intervals based on the cardinality of a maximum cardinality clique and the weight of a clique is the summation of the weights of the intervals in the clique.
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Efficient parallel recognition of some circular arc graphs, II
TL;DR: An accurate proof of the characterization of proper circular arc graphs is presented and the first efficient parallel algorithm which not only recognizes proper circular arcs graphs but also constructs proper circularArc representations is obtained.
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Finding a minimal cover for binary images: An optimal parallel algorithm
TL;DR: This work derives an optimal parallel algorithm for theminimal square cover problem, which for any desired computation timeT in [logn,n] runs on an EREW-PRAM with (n/T) processors.
Journal ArticleDOI
Parallel prefix computation with few processors
Ömer Eǧecioǧlu,Çetin Kaya Koç +1 more
TL;DR: The algorithm is compared with the distributed-memory implementation of the parallel prefix algorithm proposed by Kruskal, Rudolph, and Snir and is shown to be more efficient when n is large and p 2 (p − 1) ≤ 4 τ .
Journal ArticleDOI
Parallel algorithms for evaluating sequences of set-manipulation operations
TL;DR: In this paper, the authors investigate the parallel complexity of finding the response to every operation in an off-line sequence of set manipulation operations and returning the resulting set, and show that the problem of evaluating S is in NC for various combinations of common set manipulations.