Search results for "Grid computing"

The ATLAS Simulation Infrastructure

2010

52 páginas, 10 figuras, 18 tablas.-- This article is distributed under the terms of the Creative Commons Attribution Noncommercial License.-- et al. (The ATLAS Collaboration).

Un metodo meshfree particellare per la risoluzione delle equazioni di Maxwell: sviluppo di un codice in ambiente GRID

2008

A Grid Enabled Parallel Hybrid Genetic Algorithm for SPN

2004

This paper presents a combination of a parallel Genetic Algorithm (GA) and a local search methodology for the Steiner Problem in Networks (SPN). Several previous papers have proposed the adoption of GAs and others metaheuristics to solve the SPN demonstrating the validity of their approaches. This work differs from them for two main reasons: the dimension and the features of the networks adopted in the experiments and the aim from which it has been originated. The reason that aimed this work was namely to assess deterministic and computationally inexpensive algorithms which can be used in practical engineering applications, such as the multicast transmission in the Internet. The large dimen…

Enhancing Privacy and Authorization Control Scalability in the Grid through Ontologies

2009

The use of data Grids for sharing relevant data has proven to be successful in many research disciplines. However, the use of these environments when personal data are involved (such as in health) is reduced due to its lack of trust. There are many approaches that provide encrypted storages and key shares to prevent the access from unauthorized users. However, these approaches are additional layers that should be managed along with the authorization policies. We present in this paper a privacy-enhancing technique that uses encryption and relates to the structure of the data and their organizations, providing a natural way to propagate authorization and also a framework that fits with many u…

Notice of Violation of IEEE Publication Principles<BR>An adaptive routing mechanism for P2P resource discovery

2005

The key to the usability of large-scale decentralize peer-to-peer (P2P) systems, and one of the most challenge design aspects, is efficient mechanism for distributed resource discovery. Unstructured P2P networks are very attractive because they do not suffer the limitations of centralized systems an the drawbacks of highly structured approaches. However the search algorithms are usually based on simple flooding scheme generating large loads on the network participants. In this paper to address this major limitation, we present the design an evaluation of an innovative searching protocol in unstructured P2P networks. The approach aims at dynamically adapting the network topology to peers' in…

The Argo YBJ daq system and the GRID based data transfer

2008

The Argo-YBJ experiment has now reached itsfinal design configuration. The detector system consists of a fullcoverage array (about 5800 square meters) of Resistive PlateChambers (RPCs). The throughput depends on the trigger rateand threshold. The DAQ system must be able to sustain a max-imum transfer rate of the order of 15 MB/s and a high peakdata flow. Data are read out using a typical front-end acquisitionchain built around a custom bus. Specialized electronics have beendesigned and dedicated software has been written to perform thistask. Data are sent to the online farm through a switch exploitinga gigabit ethernet protocol. A solution to transfer data from theYBJ laboratory to the labo…

COOL, LCG Conditions Database for the LHC Experiments: Development and Deployment Status

2008

The Large Hadron Collider (LHC), the world’s largest and highest-energy particle accelerator, designed to collide opposing beams of protons or lead ions, started its operations in September 2008 at the European Organization for Nuclear Research (CERN) in Geneva, Switzerland. To process and analyze the huge amounts of data generated by the four experiments installed at different collision points along the LHC ring, a large distributed computing infrastructure has been set up, the LHC Computing Grid (LCG). The bulk of this data, referred to as ‘event data’, will record the signals left in the sub-detectors of the four LHC experiments by the passage of the particles generated in the collision …

Mobile agents and grid computing

2004

Publisher Summary This chapter describes mobile agents as an effective solution for grid service provision. A short overview is first introduced on the grid paradigm and the most known research activities in the field. Then, mobile agents are discussed and a comparison with the remote procedure call (RPC) method is made as far as the most effective solution to minimize network overload and fault occurrences is concerned. The common feature of all grid architectures is a coordinated and controlled resource sharing between the members of a dynamic multi-institutional virtual community. Community members agree on a set of sharing rules and permissions, by which resources to be shared and membe…

Mobile agents, globus and resource discovery

2004

Publisher Summary This chapter discusses grid technology and some related problem. The overview of grids, in terms of application fields and needed protocols is given. The common feature of all grid architectures is a coordinated and controlled resource sharing between the members of a dynamic multi-institutional virtual community. The members of such a community agree on which resources will be shared and which members of the community will be enabled to access these resources, thus defining a set of sharing rules and permissions. The Globus project is discussed, which is nowadays the de facto standard for grid environments, with emphasis on its resource discovery components. Finally, the …

MHD Modeling of Accretion Processes in Young Stars with the PLUTO Code

2008

As shown by observations, many young stars (age<5-10 Myr) harbor a circumstellar disk and accrete material from it through the star-disk magnetosphere. Despite the large amount of observational data in the infrared, optical and X-ray bands, different issues regarding star-disk interactions are still yet open. Many of these issues need detailed physical models of the star-disk system for a better insight. To this end, we are developing a model describing the interaction between the accreting material and the star atmosphere, using the 3D Magneto-HydroDynamical (MHD) code PLUTO developed at the University of Torino. We plan to perform a set of demanding simulations on the PI2S2 Grid infrastru…