28 research outputs found
Connect Four and Graph Decomposition
We introduce the standard decomposition, a way of decomposing a labeled graph
into a sum of certain labeled subgraphs. We motivate this graph-theoretic
concept by relating it to Connect Four decompositions of standard sets. We
prove that all standard decompositions can be generated in polynomial time,
which implies that all Connect Four decompositions can be generated in
polynomial time
The Slice Algorithm For Irreducible Decomposition of Monomial Ideals
Irreducible decomposition of monomial ideals has an increasing number of
applications from biology to pure math. This paper presents the Slice Algorithm
for computing irreducible decompositions, Alexander duals and socles of
monomial ideals. The paper includes experiments showing good performance in
practice.Comment: 25 pages, 8 figures. See http://www.broune.com/ for the data use
gpucc: An Open-Source GPGPU Compiler
Abstract Graphics Processing Units have emerged as powerful accelerators for massively parallel, numerically intensive workloads. The two dominant software models for these devices are NVIDIA's CUDA and the cross-platform OpenCL standard. Until now, there has not been a fully open-source compiler targeting the CUDA environment, hampering general compiler and architecture research and making deployment difficult in datacenter or supercomputer environments. In this paper, we present gpucc, an LLVM-based, fully open-source, CUDA compatible compiler for high performance computing. It performs various general and CUDAspecific optimizations to generate high performance code. The Clang-based frontend supports modern language features such as those in C++11 and C++14. Compile time is 8% faster than NVIDIA's toolchain (nvcc) and it reduces compile time by up to 2.4x for pathological compilations (>100 secs), which tend to dominate build times in parallel build environments. Compared to nvcc, gpucc's runtime performance is on par for several open-source benchmarks, such as Rodinia (0.8% faster), SHOC (0.5% slower), or Tensor (3.7% faster). It outperforms nvcc on internal large-scale end-to-end benchmarks by up to 51.0%, with a geometric mean of 22.9%
The PhyloPythiaS Web Server for Taxonomic Assignment of Metagenome Sequences
Metagenome sequencing is becoming common and there is an increasing need for easily accessible tools for data analysis. An essential step is the taxonomic classification of sequence fragments. We describe a web server for the taxonomic assignment of metagenome sequences with PhyloPythiaS. PhyloPythiaS is a fast and accurate sequence composition-based classifier that utilizes the hierarchical relationships between clades. Taxonomic assignments with the web server can be made with a generic model, or with sample-specific models that users can specify and create. Several interactive visualization modes and multiple download formats allow quick and convenient analysis and downstream processing of taxonomic assignments. Here, we demonstrate usage of our web server by taxonomic assignment of metagenome samples from an acidophilic biofilm community of an acid mine and of a microbial community from cow rumen
Aspekte van die grammatika van die vergelykingskonstruksie in Afrikaans
Tesis (M.A.) -- -Universiteit van Stellenbosch, 1984.Full text to be digitised and attached to bibliographic record