10,331 research outputs found
A multiphysics and multiscale software environment for modeling astrophysical systems
We present MUSE, a software framework for combining existing computational
tools for different astrophysical domains into a single multiphysics,
multiscale application. MUSE facilitates the coupling of existing codes written
in different languages by providing inter-language tools and by specifying an
interface between each module and the framework that represents a balance
between generality and computational efficiency. This approach allows
scientists to use combinations of codes to solve highly-coupled problems
without the need to write new codes for other domains or significantly alter
their existing codes. MUSE currently incorporates the domains of stellar
dynamics, stellar evolution and stellar hydrodynamics for studying generalized
stellar systems. We have now reached a "Noah's Ark" milestone, with (at least)
two available numerical solvers for each domain. MUSE can treat multi-scale and
multi-physics systems in which the time- and size-scales are well separated,
like simulating the evolution of planetary systems, small stellar associations,
dense stellar clusters, galaxies and galactic nuclei.
In this paper we describe three examples calculated using MUSE: the merger of
two galaxies, the merger of two evolving stars, and a hybrid N-body simulation.
In addition, we demonstrate an implementation of MUSE on a distributed computer
which may also include special-purpose hardware, such as GRAPEs or GPUs, to
accelerate computations. The current MUSE code base is publicly available as
open source at http://muse.liComment: 24 pages, To appear in New Astronomy Source code available at
http://muse.l
Integrating Existing Software Toolkits into VO System
Virtual Observatory (VO) is a collection of interoperating data archives and
software tools. Taking advantages of the latest information technologies, it
aims to provide a data-intensively online research environment for astronomers
all around the world.
A large number of high-qualified astronomical software packages and libraries
are powerful and easy of use, and have been widely used by astronomers for many
years. Integrating those toolkits into the VO system is a necessary and
important task for the VO developers.
VO architecture greatly depends on Grid and Web services, consequently the
general VO integration route is "Java Ready - Grid Ready - VO Ready". In the
paper, we discuss the importance of VO integration for existing toolkits and
discuss the possible solutions. We introduce two efforts in the field from
China-VO project, "gImageMagick" and " Galactic abundance gradients statistical
research under grid environment". We also discuss what additional work should
be done to convert Grid service to VO service.Comment: 9 pages, 3 figures, will be published in SPIE 2004 conference
proceeding
VM-MAD: a cloud/cluster software for service-oriented academic environments
The availability of powerful computing hardware in IaaS clouds makes cloud
computing attractive also for computational workloads that were up to now
almost exclusively run on HPC clusters.
In this paper we present the VM-MAD Orchestrator software: an open source
framework for cloudbursting Linux-based HPC clusters into IaaS clouds but also
computational grids. The Orchestrator is completely modular, allowing flexible
configurations of cloudbursting policies. It can be used with any batch system
or cloud infrastructure, dynamically extending the cluster when needed. A
distinctive feature of our framework is that the policies can be tested and
tuned in a simulation mode based on historical or synthetic cluster accounting
data.
In the paper we also describe how the VM-MAD Orchestrator was used in a
production environment at the FGCZ to speed up the analysis of mass
spectrometry-based protein data by cloudbursting to the Amazon EC2. The
advantages of this hybrid system are shown with a large evaluation run using
about hundred large EC2 nodes.Comment: 16 pages, 5 figures. Accepted at the International Supercomputing
Conference ISC13, June 17--20 Leipzig, German
Grids and the Virtual Observatory
We consider several projects from astronomy that benefit from the Grid paradigm and
associated technology, many of which involve either massive datasets or the federation
of multiple datasets. We cover image computation (mosaicking, multi-wavelength
images, and synoptic surveys); database computation (representation through XML,
data mining, and visualization); and semantic interoperability (publishing, ontologies,
directories, and service descriptions)
OpenMinTeD: A Platform Facilitating Text Mining of Scholarly Content
The OpenMinTeD platform aims to bring full text Open Access scholarly content from a wide range of providers together with Text and Data Mining (TDM) tools from various Natural Language Processing frameworks and TDM developers in an integrated environment. In this way, it supports users who want to mine scientific literature with easy access to relevant content and allows running scalable TDM workflows in the cloud
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