A5090946053- Distributed and Parallel Computing Systems
- Scientific Computing and Data Management
- Nuclear physics research studies
- Parallel Computing and Optimization Techniques
- Cloud Computing and Resource Management
- Advanced Data Storage Technologies
- Advanced Chemical Physics Studies
- Quantum Chromodynamics and Particle Interactions
- Access Control and Trust
- Quantum, superfluid, helium dynamics
- Particle physics theoretical and experimental studies
- Smart Grid Security and Resilience
- Distributed systems and fault tolerance
- Atomic and Molecular Physics
- Nuclear Physics and Applications
- Advanced NMR Techniques and Applications
- Peer-to-Peer Network Technologies
- Research Data Management Practices
- Particle Detector Development and Performance
- Atomic and Subatomic Physics Research
- Service-Oriented Architecture and Web Services
- Experimental Learning in Engineering
- Atmospheric Ozone and Climate
- Scientific Research and Discoveries
- Information and Cyber Security
National Institute for Subatomic Physics
2007-2021
Leibniz Supercomputing Centre
2021
Karlsruhe Institute of Technology
2021
Rutherford Appleton Laboratory
2021
SURF
2021
Aristotle University of Thessaloniki
2005
Leiden University
2004
The aim of the EGEE (Enabling Grids for E-Science in Europe) project is to create a reliable and dependable European Grid infrastructure e-Science. objective Middleware Re-engineering Integration Research Activity provide robust middleware components, deployable on several platforms operating systems, corresponding core services resource access, data management, information collection, authentication & authorization, matchmaking brokering, monitoring accounting. For achieving this objective,...
The reaction 16O(e,e′pp)14C has been studied at a transferred four-momentum (ω,|q|)=(210MeV,300MeV/c). differential cross sections for the transitions to ground state and lowest excited states in 14C were determined as function of momentum recoiling nucleus angle between proton emitted forward direction transfer q. A comparison data results calculations, performed with microscopic model, shows clear signatures short-range correlations 16O state.Received 23 April...
In a computational Grid which consists of many computer clusters, job start time predictions are useful to guide resource selections and balance the workload distribution. However, basic middleware available today either has no means expressing that site will take before starting or uses simple linear scale. this paper we introduce system for predicting times on clusters. Our based statistical analysis historical traces simulation schedulers. We have deployed EDG (European Data-Grid)...
The Grid‐based Virtual Laboratory AMsterdam (VLAM‐G), provides a science portal for distributed analysis in applied scientific research. It offers scientists remote experiment control, data management facilities and access to resources by providing cross‐institutional integration of information familiar environment. main goal is provide unique existing standards software packages. This paper describes the design prototype implementation VLAM‐G platform. In this testbed we several recent...
The reaction ${}^{16}\mathrm{O}({e,e}^{\ensuremath{'}}\mathrm{pp})$ has been studied at a transferred four-momentum $(\ensuremath{\omega},|\mathbf{q}|)\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}(210\mathrm{MeV},300\mathrm{MeV}/c)$. Evidence obtained for direct knockout of proton pairs from the 1p shell. excitation-energy spectrum residual nucleus and missing-momentum densities indicate that $^{1}S_{0}$ pair dominates reaction, while there is also noticeable contribution ${}^{3}P$ pairs.
In large-scale grids with many possible resources (clusters of computing elements) to run applications, it is useful that the can provide predictions job response times so users or resource brokers make better scheduling decisions. Two metrics need be estimated for time predictions: one how long a executes on (application time), other waits in queue before starting (queue wait time). this paper we propose an instance based learning technique predict these two by mining historical workloads....
In this paper we present an initial analysis of job failures in a large-scale data-intensive Grid. Based on three representative periods production, characterize the interarrival times and life spans failed jobs. Different failure types are distinguished is carried out further at Virtual Organization (VO) level. The spatial behavior, namely where occur Grid, also examined. Cross-correlation structures, including how arrivals correlate with failures, analyzed illustrated. We investigate...
The majority of compute resources in todays scientific grids are based on Unix and Unix-like operating systems. In this world, user user-group management around the concepts a numeric 'user ID' 'group that local to resource. contrast, grid group centered globally assigned identifiers VO membership, structures independent any specific At fabric boundary, these 'grid identities' have be translated IDs. New job submission methodologies, such as job-execution web services, community-deployed...
The security models used in Grid systems today strongly bear the marks of their diverse origin. Historically retrofitted to distributed they are designed protect and control, model is usually limited scope applicability, its implementation tailored towards a few specific deployment scenarios. A common approach even "basic" elements such as authentication resources only now emerging, whereas for more complex issues community organization, integration site access control with operating...
Cross sections for the ${}^{3}\mathrm{He}{(e,e}^{\ensuremath{'}}pp)n$ reaction were measured over a wide range of energy and three-momentum transfer. At momentum transfer $q=375\mathrm{MeV}/c,$ data taken at transferred energies $\ensuremath{\omega}$ ranging from 170 to 290 MeV. $\ensuremath{\omega}=220\mathrm{MeV},$ measurements performed three q values (305, 375, $445\mathrm{MeV}/c).$ The results are presented as function neutron in final state, transfer, relative two-proton system....
In this paper we present an initial analysis of job failures in a large-scale data-intensive Grid. Based on three representative periods production, characterize the interarrival times and life spans failed jobs. Different failure types are distinguished is carried out further at Virtual Organization (VO) level. The spatial behavior, namely where occur Grid, also examined. Cross-correlation structures, including how arrivals correlate with failures, analyzed illustrated. We investigate...
The Grid security mechanisms were designed under the assumption that users would submit their jobs directly to gatekeepers. However, many groups are starting use pilot-based infrastructures, where a centralized queue and successively transferred resources by pilot infrastructure. While this approach greatly improves user experience, it does introduce several policy issues, more serious being lack of system level protection between inability for sites apply fine grained authorization...
Cross sections for the ${}^{3}\mathrm{He}({e,e}^{\ensuremath{'}}\mathrm{pp})n$ reaction were measured at an energy transfer of 220 MeV and three-momentum transfers $q$ 305, 375, $445\mathrm{MeV}/c$. Results are presented as a function final-state neutron momentum slices in specific kinematic variables. At low momenta, comparison data to results continuum Faddeev calculations performed with Bonn- $B$ nucleon-nucleon potential indicates dominant role two-proton knockout induced by one-body...
Abstract The D0 experiment has used the European DataGrid (EDG) testbed to reprocess real data obtained from Tevatron collider at Fermi National Accelerator Laboratory. Pushing use of EDG software beyond feasibility studies produced a set recommendations for authors experiment‐level software, producers middleware and designers Grid systems. This paper describes experience with resulting recommendations. Copyright © 2005 John Wiley & Sons, Ltd.
The Open Science Grid (OSG) and the Enabling Grids for E-sciencE (EGEE) have a common security model, based on Public Key Infrastructure. resources grant access to users because of their membership in Virtual Organization (VO), rather than personal identity. Users push VO information form identity attributes, thus declaring that will be consumed behalf specific group inside organizational structure VO. Resources contact an policies repository, centralized at each site, appropriate privileges...