20,901 research outputs found
From Quantity to Quality: Massive Molecular Dynamics Simulation of Nanostructures under Plastic Deformation in Desktop and Service Grid Distributed Computing Infrastructure
The distributed computing infrastructure (DCI) on the basis of BOINC and
EDGeS-bridge technologies for high-performance distributed computing is used
for porting the sequential molecular dynamics (MD) application to its parallel
version for DCI with Desktop Grids (DGs) and Service Grids (SGs). The actual
metrics of the working DG-SG DCI were measured, and the normal distribution of
host performances, and signs of log-normal distributions of other
characteristics (CPUs, RAM, and HDD per host) were found. The practical
feasibility and high efficiency of the MD simulations on the basis of DG-SG DCI
were demonstrated during the experiment with the massive MD simulations for the
large quantity of aluminum nanocrystals (-). Statistical
analysis (Kolmogorov-Smirnov test, moment analysis, and bootstrapping analysis)
of the defect density distribution over the ensemble of nanocrystals had shown
that change of plastic deformation mode is followed by the qualitative change
of defect density distribution type over ensemble of nanocrystals. Some
limitations (fluctuating performance, unpredictable availability of resources,
etc.) of the typical DG-SG DCI were outlined, and some advantages (high
efficiency, high speedup, and low cost) were demonstrated. Deploying on DG DCI
allows to get new scientific from the simulated
of numerous configurations by harnessing sufficient computational power to
undertake MD simulations in a wider range of physical parameters
(configurations) in a much shorter timeframe.Comment: 13 pages, 11 pages (http://journals.agh.edu.pl/csci/article/view/106
Survey and Analysis of Production Distributed Computing Infrastructures
This report has two objectives. First, we describe a set of the production
distributed infrastructures currently available, so that the reader has a basic
understanding of them. This includes explaining why each infrastructure was
created and made available and how it has succeeded and failed. The set is not
complete, but we believe it is representative.
Second, we describe the infrastructures in terms of their use, which is a
combination of how they were designed to be used and how users have found ways
to use them. Applications are often designed and created with specific
infrastructures in mind, with both an appreciation of the existing capabilities
provided by those infrastructures and an anticipation of their future
capabilities. Here, the infrastructures we discuss were often designed and
created with specific applications in mind, or at least specific types of
applications. The reader should understand how the interplay between the
infrastructure providers and the users leads to such usages, which we call
usage modalities. These usage modalities are really abstractions that exist
between the infrastructures and the applications; they influence the
infrastructures by representing the applications, and they influence the ap-
plications by representing the infrastructures
A Taxonomy of Data Grids for Distributed Data Sharing, Management and Processing
Data Grids have been adopted as the platform for scientific communities that
need to share, access, transport, process and manage large data collections
distributed worldwide. They combine high-end computing technologies with
high-performance networking and wide-area storage management techniques. In
this paper, we discuss the key concepts behind Data Grids and compare them with
other data sharing and distribution paradigms such as content delivery
networks, peer-to-peer networks and distributed databases. We then provide
comprehensive taxonomies that cover various aspects of architecture, data
transportation, data replication and resource allocation and scheduling.
Finally, we map the proposed taxonomy to various Data Grid systems not only to
validate the taxonomy but also to identify areas for future exploration.
Through this taxonomy, we aim to categorise existing systems to better
understand their goals and their methodology. This would help evaluate their
applicability for solving similar problems. This taxonomy also provides a "gap
analysis" of this area through which researchers can potentially identify new
issues for investigation. Finally, we hope that the proposed taxonomy and
mapping also helps to provide an easy way for new practitioners to understand
this complex area of research.Comment: 46 pages, 16 figures, Technical Repor
Parallel memetic algorithms for independent job scheduling in computational grids
In this chapter we present parallel implementations of Memetic Algorithms (MAs) for the problem of scheduling independent jobs in computational grids. The problem of scheduling in computational grids is known for its high demanding computational time. In this work we exploit the intrinsic parallel nature of MAs as well as the fact that computational grids offer large amount of resources, a part of which could be used to compute the efficient allocation of jobs to grid resources.
The parallel models exploited in this work for MAs include both fine-grained and coarse-grained parallelization and their hybridization. The resulting schedulers have been tested through different grid scenarios generated by a grid simulator to match different possible configurations of computational grids in terms of size (number of jobs and resources) and computational characteristics of resources. All in all, the result of this work showed that Parallel MAs are very good alternatives in order to match different performance requirement on fast scheduling of jobs to grid resources.Peer ReviewedPostprint (author's final draft
Securing a business loan : how important is gender
This report examines the role of gender in business and evalates whether there is a evidence of gender bias when it comes to securing bank loans
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