Search results for "computational science"
showing 10 items of 124 documents
Interfaces in immiscible polymer blends: A Monte Carlo simulation approach on the CRAY T3E
1999
Polymeric materials pose a challenge for Monte Carlo simulations because of the widely spread length and time scales involved. Using large scale computer simulations we investigate the interfacial structure in a partially compatible polymer mixture. The problem is studied in the framework of a coarse grained lattice model - the bond fluctuation model on the simple cubic lattice, choosing N = 32 and lattice linear dimensions L × L × D up to 512 × 512 × 64. We employ a two dimensional geometric decomposition scheme to implement this algorithm on the CRAY T3E. The algorithm scales very well with the number of processors. The structure of polymer coils near interfaces between coexisting phases …
GPU accelerated Monte Carlo simulations of lattice spin models
2011
We consider Monte Carlo simulations of classical spin models of statistical mechanics using the massively parallel architecture provided by graphics processing units (GPUs). We discuss simulations of models with discrete and continuous variables, and using an array of algorithms ranging from single-spin flip Metropolis updates over cluster algorithms to multicanonical and Wang-Landau techniques to judge the scope and limitations of GPU accelerated computation in this field. For most simulations discussed, we find significant speed-ups by two to three orders of magnitude as compared to single-threaded CPU implementations.
Reliable computation and local mesh adaptivity in limit analysis
2019
The contribution is devoted to computations of the limit load for a perfectly plastic model with the von Mises yield criterion. The limit factor of a prescribed load is defined by a specific variational problem, the so-called limit analysis problem. This problem is solved in terms of deformation fields by a penalization, the finite element and the semismooth Newton methods. From the numerical solution, we derive a guaranteed upper bound of the limit factor. To achieve more accurate results, a local mesh adaptivity is used. peerReviewed
A CUDA-based implementation of an improved SPH method on GPU
2021
We present a CUDA-based parallel implementation on GPU architecture of a modified version of the Smoothed Particle Hydrodynamics (SPH) method. This modified formulation exploits a strategy based on the Taylor series expansion, which simultaneously improves the approximation of a function and its derivatives with respect to the standard formulation. The improvement in accuracy comes at the cost of an additional computational effort. The computational demand becomes increasingly crucial as problem size increases but can be addressed by employing fast summations in a parallel computational scheme. The experimental analysis showed that our parallel implementation significantly reduces the runti…
CUDA-BLASTP: Accelerating BLASTP on CUDA-enabled graphics hardware
2011
Scanning protein sequence database is an often repeated task in computational biology and bioinformatics. However, scanning large protein databases, such as GenBank, with popular tools such as BLASTP requires long runtimes on sequential architectures. Due to the continuing rapid growth of sequence databases, there is a high demand to accelerate this task. In this paper, we demonstrate how GPUs, powered by the Compute Unified Device Architecture (CUDA), can be used as an efficient computational platform to accelerate the BLASTP algorithm. In order to exploit the GPU's capabilities for accelerating BLASTP, we have used a compressed deterministic finite state automaton for hit detection as wel…
Knowledge mining of unstructured information: application to cyber domain
2023
Funding Information: TT, KB, ML and KK acknowledge research project funding from Cyberwatch Finland. AC is the CEO of the company. PJ and AC are founders and partners in the company. KK and ML are on the advisory board of the company. Funding Information: TT, KB, ML and KK acknowledge research project funding from Cyberwatch Finland. TT acknowledges funding from the Vilho, Yrjö and Kalle Väisälä Foundation of the Finnish Academy of Science and Letters. Publisher Copyright: © 2023, The Author(s). Information on cyber-related crimes, incidents, and conflicts is abundantly available in numerous open online sources. However, processing large volumes and streams of data is a challenging task for…
Potential and challenges in home care service process optimization : a route optimization approach
2016
Aging of the population is an increasing problem in many countries, including Finland, and it poses a challenge to public services such as home care. Vehicle routing optimization (VRP) type optimization solutions are one possible way to decrease the time required for planning home visits and driving to customer addresses, as well as decreasing transportation costs. Although VRP optimization is widely and succesfully applied to commercial and industrial logistics, the home care is a relatively new application area for it. This thesis examines what kind of distance and time savings would be possible to achieve if daily home care operations are optimized in the similar manner as typical VRP op…
EOF-Library: Open-source Elmer FEM and OpenFOAM coupler for electromagnetics and fluid dynamics
2019
EOF-Library is a software that couples Elmer and OpenFOAM simulation packages. It enables efficient internal field interpolation and communication between the finite element and the finite volume frameworks. The coupling of the two packages is based on the Message Passing Interface, which results in low latency, high data bandwidth and parallel scalability. Potential applications are magnetohydrodynamics, convective cooling of electrical devices, industrial plasma physics and microwave heating. In this work we introduce the software and perform interpolation accuracy and parallel scaling tests by sending a known scalar distribution between the two codes. Keywords: Elmer, FEM, OpenFOAM, FVM,…
Kinematics of perceived dyadic coordination in dance
2019
We investigated the relationships between perceptions of similarity and interaction in spontaneously dancing dyads, and movement features extracted using novel computational methods. We hypothesized that dancers’ movements would be perceived as more similar when they exhibited spatially and temporally comparable movement patterns, and as more interactive when they spatially oriented more towards each other. Pairs of dancers were asked to move freely to two musical excerpts while their movements were recorded using optical motion capture. Subsequently, in two separate perceptual experiments we presented stick figure animations of the dyads to observers, who rated degree of interaction and si…
Euclid preparation: XI. Mean redshift determination from galaxy redshift probabilities for cosmic shear tomography
2021
Ilbert, O., et al. (Euclid Collaboration)