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Global Arrays
Global Arrays, or GA, is the library developed by scientists at Pacific Northwest National Laboratory for parallel computing. GA provides a friendly API for shared-memory programming on distributed-memory computers for multidimensional arrays. The GA library is a predecessor to the GAS ( global address space) languages currently being developed for high-performance computing. The GA toolkit has additional libraries including a Memory Allocator (MA), Aggregate Remote Memory Copy Interface (ARMCI), and functionality for out-of-core storage of arrays (ChemIO). Although GA was initially developed to run with TCGMSG, a message passing library that came before the MPI standard ( Message Passing Interface), it is now fully compatible with MPI. GA includes simple matrix computations (matrix-matrix multiplication, LU solve) and works with ScaLAPACK. Sparse matrices are available but the implementation is not optimal yet. GA was developed by Jarek Nieplocha, Robert Harrison, R. J. Litt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parallel Programming
Parallel computing is a type of computation in which many calculations or processes are carried out simultaneously. Large problems can often be divided into smaller ones, which can then be solved at the same time. There are several different forms of parallel computing: bit-level, instruction-level, data, and task parallelism. Parallelism has long been employed in high-performance computing, but has gained broader interest due to the physical constraints preventing frequency scaling.S.V. Adve ''et al.'' (November 2008)"Parallel Computing Research at Illinois: The UPCRC Agenda" (PDF). Parallel@Illinois, University of Illinois at Urbana-Champaign. "The main techniques for these performance benefits—increased clock frequency and smarter but increasingly complex architectures—are now hitting the so-called power wall. The computer industry has accepted that future performance increases must largely come from increasing the number of processors (or cores) on a die, rather than ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TURBOMOLE
TURBOMOLE is an ab initio computational chemistry program that implements various quantum chemistry methods. It was initially developed by the group of Prof. Reinhart Ahlrichs at the University of Karlsruhe. In 2007, TURBOMOLE GmbH, founded by R. Ahlrichs, F. Furche, C. Hättig, W. Klopper, M. Sierka, and F. Weigend, took over the responsibility for the coordination of the scientific development of TURBOMOLE program, for which the company holds all copy and intellectual property rights. In 2018 David P. Tew joined the TURBOMOLE GmbH. Since 1987, this program is one of the useful tools as it involves in many fields of research including heterogeneous and homogeneous catalysis, organic and inorganic chemistry, spectroscopy as well as biochemistry. This can be illustrated by citation records of Ahlrich's 1989 publication which is more than 6700 times as of 18 July 2020. In the year 2014, the second Turbomole article has been published. The number of citations from both papers indica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MOLCAS
MOLCAS is an ab initio computational chemistry program, developed as a joint project by a number of international institutes. MOLCAS is developed by scientists to be used by scientists. It is not primarily a commercial product and it is not sold in order to produce a fortune for its owner (the Lund University). Focus in the program is placed on methods for calculating general electronic structures in both ground and excited states. MOLCAS contains codes for general and effective multiconfigurational SCF calculations at the Complete Active Space (CASSCF) level, but also employing more restricted MCSCF wave functions (RASSCF). It is also possible, at this level of theory, to optimize geometries for equilibrium and transition states using gradient techniques and to compute force fields and vibrational energies. MOLCAS also contains second order perturbation theory codes CASPT2 and RASPT2. History MOLCAS code has been created at the late 1980s by the group of Prof. Björn O. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MOLPRO
MOLPRO is a software package used for accurate ''ab initio'' quantum chemistry calculations. It is developed by Peter Knowles at Cardiff University and Hans-Joachim Werner at Universität Stuttgart in collaboration with other authors. The emphasis in the program is on highly accurate computations, with extensive treatment of the electron correlation problem through the multireference configuration interaction, coupled cluster and associated methods. Integral-direct local electron correlation methods reduce the increase of the computational cost with molecular size. Accurate ab initio calculations can then be performed for larger molecules. With new explicitly correlated methods the basis set limit can be very closely approached. History Molpro was designed and maintained by Wilfried Meyer and Peter Pulay Peter Pulay (born September 20, 1941, in Veszprém, Hungary) is a theoretical chemist. He is the Roger B. Bost Distinguished Professor of Chemistry in the Department of Chemis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NWChem
NWChem is an ab initio computational chemistry software package which includes quantum chemical and molecular dynamics functionality. It was designed to run on high-performance parallel supercomputers as well as conventional workstation clusters. It aims to be scalable both in its ability to treat large problems efficiently, and in its usage of available parallel computing resources. NWChem has been developed by the Molecular Sciences Software group of the Theory, Modeling & Simulation program of the Environmental Molecular Sciences Laboratory (EMSL) at the Pacific Northwest National Laboratory (PNNL). The early implementation was funded by the EMSL Construction Project. NWChem is currently being redesigned and reimplemented for exascale computing platforms (NWChemEx ). Capabilities * Molecular mechanics * Molecular dynamics * Hartree–Fock (self-consistent field method) * Density functional theory * Time-dependent density functional theory * Post-Hartree–Fock me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ian Foster (computer Scientist)
Ian Tremere Foster (born 1 January 1959) is a New Zealand-American computer scientist. He is a distinguished fellow, senior scientist, and director of the Data Science and Learning division at Argonne National Laboratory, and a professor in the department of computer science at the University of Chicago. Education and career Foster was born in Wellington, New Zealand, in 1959. He was educated at Wellington College, Wellington, Wellington College and the University of Canterbury, followed by the Department of Computing, Imperial College London, Department of Computing, Imperial College London. From 2006 to 2016, he was director of the Computation Institute (CI), a joint project between the University of Chicago, and Argonne National Laboratory. CI brings together computational scientists and discipline leaders to work on projects with computation as a key component. He is currently Director of the Data Science and Learning Division at Argonne National Laboratory, a unit establi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ScaLAPACK
The ScaLAPACK (or Scalable LAPACK) library includes a subset of LAPACK routines redesigned for distributed memory MIMD parallel computers. It is currently written in a Single-Program-Multiple-Data style using explicit message passing for interprocessor communication. It assumes matrices are laid out in a two-dimensional block cyclic decomposition. ScaLAPACK is designed for heterogeneous computing and is portable on any computer that supports MPI or PVM. ScaLAPACK depends on PBLAS operations in the same way LAPACK depends on BLAS. As of version 2.0 the code base directly includes PBLAS and BLACS and has dropped support for PVM. Examples *Programming with Big Data in R fully utilizes ScaLAPACK and two-dimensional block cyclic decomposition for Big Data Though used sometimes loosely partly because of a lack of formal definition, the interpretation that seems to best describe Big data is the one associated with large body of information that we could not comprehend when used o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Global Address Space
In computer science, partitioned global address space (PGAS) is a parallel programming model paradigm. PGAS is typified by communication operations involving a global memory address space abstraction that is logically partitioned, where a portion is local to each process, thread, or processing element. The novelty of PGAS is that the portions of the shared memory space may have an affinity for a particular process, thereby exploiting locality of reference in order to improve performance. A PGAS memory model is featured in various parallel programming languages and libraries, including: Coarray Fortran, Unified Parallel CSplit-C Fortress, Chapel, X10UPC++ [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pacific Northwest National Laboratory
Pacific Northwest National Laboratory (PNNL) is one of the United States Department of Energy national laboratories, managed by the Department of Energy's (DOE) Office of Science. The main campus of the laboratory is in Richland, Washington. Originally named the Pacific Northwest Laboratory, PNL was established in 1965 when research and development at the Hanford Site was separated from other Hanford operations. In 1995, the laboratory was renamed the Pacific Northwest National Laboratory also known as PNNL. Facilities PNNL houses several scientific user facilities and research facilities. Scientific user facilities The Environmental Molecular Sciences Laboratory (EMSL) is a U.S. Department of Energy national scientific user facility. EMSL provides researchers around the world with integrated capabilities in oxide and mineral interface chemistry, high-performance computing and computational chemistry software, mass spectrometry, high-field magnetic resonance, and subsurface ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
