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In this paper we present methods for parallelization of 3D CFD forest fire modelling code on Non-uniform memory computers in frame of the OpenMP environment. Mathematical model is presented first. Then, some peculiarities of this class of computers are considered, along with properties and limitations of the OpenMP model. Techniques for efficient parallelization are discussed, considering different...
The paper presents IARnet toolkit, a set of high-level tools and services simplifying integration of software resources into a distributed computing environment and development of distributed applications involving dynamic discovery and composition of resources. A case study of using IARnet for solving large scale discrete optimization problems is discussed.
The application of the Orthogonal Organized Finite State Machine (OOFSM) to the representation of data acquired by sensor networks is proposed. The OOFSM was proposed in earlier work; it is succinctly reviewed here. The approach and representation of the OOFSM to sensor acquired data is formalized. The usefulness of this OOFSM application is illustrated by several case studies, specifically, gradients,...
The numerical analysis of some broadband electromagnetic fields and frequency-dependent materials using a time domain method is the main subject of this paper. The spatial and time-dependent distribution of the electromagnetic field is approximated by the finite element method. The parallel form of the algorithm valid for some linear materials, and the formulation of the FE code for a dispersive electromagnetic...
Protoplanetary disc simulation must be done first, with high precision, and second, with high speed. Some strategies to reach these goals are presented in the paper. They include: the reduction of the 3D protoplanetary disc model to quasi-3D, the use of fundamental Poisson equation solution, the simulation in the natural (cylindrical) coordinate system and computation domain decomposition. The domain...
Web Search Engine uses forward indexing and inverted indexing as a part of its functional design. This indexing mechanism helps retrieving data from the database based on user query. In this paper, an efficient solution to handle the indexing problem is proposed with the introduction of Nonlinear Single Cycle Multiple Attractor Cellular Automata (SMACA). This work simultaneously shows generation of...
The running times of large-scale computational science and engineering parallel applications, executed on clusters or Grid platforms, are usually longer than the mean-time-between-failures (MTBF). Therefore, hardware failures must be tolerated to ensure that not all computation done is lost on machine failures. Checkpointing and rollback recovery are very useful techniques to implement fault-tolerant...
We describe parallel numerical code for solving problems of stellar dynamics. The code is based on numerical solving of Poisson and Vlasov equations in cylindrical coordinates using particle-in-cells method. The code is designed for use on supercomputers with distributed memory. We consider different possible strategies of parallelization according to initial technical parameters of numerical methods...
In this paper, the authors propose a numerical investigation in the time domain of the mechanical wave propagation due to an impulsional load on a semi-infinite soil. The ground is modelled as a porous saturated viscoelastic medium involving the complete Biot theory. An accurate and efficient Finite Element Method using a matrix-free technique is used. Two parallel algorithms are used: Geometrical...
The number of sequenced genes is dramatically increasing with that of international genomic projects. The gene sequence information proved to be helpful in predictions of protein structure, protein function and mutations targeted at improving the biological and biotechnological properties of proteins. Processing of the immense information stored in the databases demands high-throughput computational...
The paper presents a set of theoretical experiments performed to evaluate Situated Cellular Agent (SCA) approach within pedestrian dynamics research context. SCA is a modeling and simulation approach based on Multi Agent Systems principles that derives from Cellular Automata. In particular, we focus on two emerging phenomena (freezing by heating and lane formation phenomena) that have been empirically...
Simulating spatial dynamics in physics by Cellular Automata (CA) requires very large computation power, and, hence, CA simulation algorithms are to be implemented on multiprocessors. The preconceived opinion, that no much effort is required to obtain highly efficient coarse grained parallel CA algorithm, is not always true. In fact, a great variety of CA modifications coming into practical use need...
Complex matter may lie in various forms from granular matter, soft matter, fluid-fluid or solid-fluid mixtures to compact heterogeneous material. Cellular automata models make a suitable and powerful tool to catch the influence of the microscopic scale onto the macroscopic behaviour of these complex systems. Rather than a survey, this paper will attempt to bring out the main concepts underlying these...
The dynamic behaviour of the CO oxidation reaction over Pd(110) has been studied by means of probabilistic asynchronous cellular automata (Dynamic Monte-Carlo). The influence of the internal parameters on the shapes of surface concentration waves obtained in simulations under the limited surface diffusion intensity conditions has been studied. The hysteresis in oscillatory behaviour has been found...
We present the design and implementation of CAOS, a domain-specific high-level programming language for the parallel simulation of extended cellular automata. CAOS allows scientists to specify complex simulations with limited programming skills and effort. Yet the CAOS compiler generates efficiently executable code that automatically harnesses the potential of contemporary multi-core processors, shared...
The general question of our investigation is: how can the simulation of moving objects (or agents) in a cellular automaton (CA) be accelerated by hardware architectures. We exemplify our approach using the creatures’ exploration problem: n creatures are moving around in an unknown environment in order to visit all cells in shortest time. This problem is modeled as CA because this model is massively...
Current industrial applications require fast and robust image processing in systems with low size and power dissipation. One of the main tasks in industrial vision is fast detection of centroids of objects. This paper compares three different approaches for finding geometric algorithms for centroid detection which are appropriate for a fine-grained parallel hardware architecture in an embedded vision...
We propose a natural implementation of Italiano’s algorithm for updating the transitive closure of directed graphs after deletion of an edge on a model of associative (content addressable) parallel systems with vertical processing (the STAR–machine). The associative version of Italiano’s decremental algorithm is given as procedure DeleteArc, whose correctness is proved and time complexity is evaluated...
It has been already verified that hardware-supported finegrain synchronization provides a significant performance improvement over coarse-grained synchronization mechanisms, such as barriers. Support for fine-grain synchronization on individual data items becomes notably important in order to efficiently exploit thread-level parallelism available on multi-threading and multi-core processors. Fine-grained...
Large Hodgkin-Huxley (HH) neural networks were examined and the structures discussed in this article simulated a part of the rat somatosensory cortex. We used a modular architecture of the network divided into layers and sub-regions. Because of a high degree of complexity effective parallelisation of algorithms was required. The results of parallel simulations were presented. An occurrence of the...
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