Now showing items 1-13 of 13

    • 1.5D parallel sparse matrix-vector multiply 

      Kayaaslan, E.; Aykanat, Cevdet; Uçar, B. (Society for Industrial and Applied Mathematics, 2018)
      There are three common parallel sparse matrix-vector multiply algorithms: 1D row-parallel, 1D column-parallel, and 2D row-column-parallel. The 1D parallel algorithms offer the advantage of having only one communication ...
    • Adapting iterative-improvement heuristics for scheduling file-sharing tasks on heterogeneous platforms 

      Kaya, Kamer; Uçar, B.; Aykanat, Cevdet (Springer, Berlin, Heidelberg, 2008)
      We consider the problem of scheduling an application on a computing system consisting of heterogeneous processors and one or more file repositories. The application consists of a large number of file-sharing, otherwise ...
    • Encapsulating multiple communication-cost metrics in partitioning sparse rectangular matrices for parallel matrix-vector multiplies 

      Uçar, B.; Aykanat, Cevdet (SIAM, 2004)
      This paper addresses the problem of one-dimensional partitioning of structurally unsymmetric square and rectangular sparse matrices for parallel matrix-vector and matrix-transpose-vector multiplies. The objective is to ...
    • Exact algorithms for a task assignment problem 

      Kaya, Kamer; Uçar, B. (World Scientific Publishing Company, 2009)
      We consider the following task assignment problem. Communicating tasks are to be assigned to heterogeneous processors interconnected with a heterogeneous network. The objective is to minimize the total sum of the execution ...
    • Heuristics for scheduling file-sharing tasks on heterogeneous systems with distributed repositories 

      Kaya, K.; Uçar, B.; Aykanat, Cevdet (Academic Press, 2007)
      We consider the problem of scheduling an application on a computing system consisting of heterogeneous processors and data repositories. The application consists of a large number of file-sharing otherwise independent ...
    • A matrix partitioning interface to PaToH in MATLAB 

      Uçar, B.; Çatalyürek, U. V.; Aykanat, Cevdet (Elsevier BV, 2010)
      We present the PaToH MATLAB Matrix Partitioning Interface. The interface provides support for hypergraph-based sparse matrix partitioning methods which are used for efficient parallelization of sparse matrix-vector ...
    • A message ordering problem in parallel programs 

      Uçar, B.; Aykanat, Cevdet (Springer, 2004)
      We consider a certain class of parallel program segments in which the order of messages sent affects the completion time. We give characterization of these parallel program segments and propose a solution to minimize the ...
    • Minimizing communication cost in fine-grain partitioning of sparse matrices 

      Uçar, B.; Aykanat, Cevdet (Springer, 2003)
      We show a two-phase approach for minimizing various communication-cost metrics in fine-grain partitioning of sparse matrices for parallel processing. In the first phase, we obtain a partitioning with the existing tools on ...
    • Multi-level direct K-way hypergraph partitioning with multiple constraints and fixed vertices 

      Aykanat, Cevdet; Cambazoglu, B. B.; Uçar, B. (Academic Press, 2008-05)
      K-way hypergraph partitioning has an ever-growing use in parallelization of scientific computing applications. We claim that hypergraph partitioning with multiple constraints and fixed vertices should be implemented using ...
    • Parallel frequent item set mining with selective item replication 

      Özkural E.; Uçar, B.; Aykanat, Cevdet (Institute of Electrical and Electronics Engineers, 2011)
      We introduce a transaction database distribution scheme that divides the frequent item set mining task in a top-down fashion. Our method operates on a graph where vertices correspond to frequent items and edges correspond ...
    • Parallel image restoration using surrogate constraint methods 

      Uçar, B.; Aykanat, Cevdet; Pınar, M. Ç.; Malas, T. (Academic Press, 2007)
      When formulated as a system of linear inequalities, the image restoration problem yields huge, unstructured, sparse matrices even for images of small size. To solve the image restoration problem, we use the surrogate ...
    • Partitioning sparse matrices for parallel preconditioned iterative methods 

      Uçar, B.; Aykanat, Cevdet (Society for Industrial and Applied Mathematics, 2007)
      This paper addresses the parallelization of the preconditioned iterative methods that use explicit preconditioners such as approximate inverses. Parallelizing a full step of these methods requires the coefficient and ...
    • Revisiting hypergraph models for sparse matrix partitioning 

      Uçar, B.; Aykanat, Cevdet (Society for Industrial and Applied Mathematics, 2007)
      We provide an exposition of hypergraph models for parallelizing sparse matrix-vector multiplies. Our aim is to emphasize the expressive power of hypergraph models. First, we set forth an elementary hypergraph model for the ...