Resource Type

Month

3 Matching Results

Results open in a new window/tab.

A Multi-Dimensional Classification Model for Scientific Workflow Characteristics (open access)

A Multi-Dimensional Classification Model for Scientific Workflow Characteristics

Workflows have been used to model repeatable tasks or operations in manufacturing, business process, and software. In recent years, workflows are increasingly used for orchestration of science discovery tasks that use distributed resources and web services environments through resource models such as grid and cloud computing. Workflows have disparate re uirements and constraints that affects how they might be managed in distributed environments. In this paper, we present a multi-dimensional classification model illustrated by workflow examples obtained through a survey of scientists from different domains including bioinformatics and biomedical, weather and ocean modeling, astronomy detailing their data and computational requirements. The survey results and classification model contribute to the high level understandingof scientific workflows.
Date: April 5, 2010
Creator: Ramakrishnan, Lavanya & Plale, Beth
System: The UNT Digital Library
The FERMI@Elettra free-electron-laser source for coherent X-ray physics: photon properties, beam transport system, and applications (open access)

The FERMI@Elettra free-electron-laser source for coherent X-ray physics: photon properties, beam transport system, and applications

FERMI@Elettra is comprised of two free electron lasers (FELs) that will generate short pulses (tau ~;; 25 to 200 fs) of highly coherent radiation in the XUV and soft X-ray region. The use of external laser seeding together with a harmonic upshift scheme to obtain short wavelengths will give FERMI@Elettra the capability to produce high quality, longitudinal coherent photon pulses. This capability together with the possibilities of temporal synchronization to external lasers and control of the output photon polarization will open new experimental opportunities not possible with currently available FELs. Here we report on the predicted radiation coherence properties and important configuration details of the photon beam transport system. We discuss the several experimental stations that will be available during initial operations in 2011, and we give a scientific perspective on possible experiments that can exploit the critical parameters of this new light source.
Date: April 5, 2010
Creator: Allaria, Enrico; Callegari, Carlo; Cocco, Daniele; Fawley, William M.; Kiskinova, Maya; Masciovecchio, Claudio et al.
System: The UNT Digital Library
Progress Towards Deployable Antineutrino Detectors for Reactor Safeguards (open access)

Progress Towards Deployable Antineutrino Detectors for Reactor Safeguards

Fission reactors emit large numbers of antineutrinos and this flux may be useful for the measurement of two quantities of interest for reactor safeguards: the reactor's power and plutonium inventory throughout its cycle. The high antineutrino flux and relatively low background rates means that simple cubic meter scale detectors at tens of meters standoff can record hundreds or thousands of antineutrino events per day. Such antineutrino detectors would add online, quasi-real-time bulk material accountancy to the set of reactor monitoring tools available to the IAEA and other safeguards agencies with minimal impact on reactor operations. Between 2003 and 2008, our LLNL/SNL collaboration successfully deployed several prototype safeguards detectors at a commercial reactor in order to test both the method and the practicality of its implementation in the field. Partially on the strength of the results obtained from these deployments, an Experts Meeting was convened by the IAEA Novel Technologies Group in 2008 to assess current antineutrino detection technology and examine how it might be incorporated into the safeguards regime. Here we present a summary of our previous deployments and discuss current work that seeks to provide expanded capabilities suggested by the Experts Panel, in particular aboveground detector operation.
Date: April 5, 2010
Creator: Bowden, N; Bernstein, A; Dazeley, S; Keefer, G; Reyna, D; Cabrera-Palmer, B et al.
System: The UNT Digital Library