Claudio Vuerli

Workflow-Based Data Parallel Applications on the EGEE Production Grid Infrastructure

Setting up and deploying complex applications on a Grid infrastructure is still challenging and the programming models are rapidly evolving. Efficiently exploiting Grid parallelism is often not straight forward. In this paper, we report on the techniques used for deploying applications on the EGEE production Grid through four experiments coming from completely different scientific areas: nuclear fusion, astrophysics and medical imaging. These applications have in common the need for manipulating huge amounts of data and all are computationally intensive. All the cases studied show that the deployment of data intensive applications require the development of more or less elaborated application-level workload management systems on top of the gLite middleware to efficiently exploit the EGEE Grid resources. In particular, the adoption of high level workflow management systems eases the integration of large scale applications while exploiting Grid parallelism transparently. Different approaches for scientific workflow management are discussed. The MOTEUR workflow manager strategy to efficiently deal with complex data flows is more particularly detailed. Without requiring specific application development, it leads to very significant speed-ups.

Active optics handling inside Galileo Telescope

A large part of the active optics system and control environment for the Galileo telescope has been developed and tested. Presently the primary mirror support cell has been characterized for the mechanical and optical aspects. The primary mirror has also been characterized and tested with the active support system in work. Part of the mechanics for the secondary and tertiary active mirror supports has been constructed and we plan to start the characterization work in the second half of this year. An overview of the main results obtained during factory acceptance tests and a discussion about the general informatics implementation is here provided.

Enabling Grid technologies for Planck space mission

PLANCK, the ESA satellite aimed at mapping the microwave sky through two complete sky surveys, will fly in 2007. It is an extremely demanding space mission in terms of computing power and data storage. PLANCK simulations mimic the whole mission starting from a virtual sky (ideal or contaminated by introducing several noise sources). Their main goal is the validation of the acquisition and reduction procedure that will be used to build the final scientific data during the operative phase of the mission. n nThe GRID technology seems to be a promising answer to data storage and processing needs of the satellite. In the framework of the EGEE grid infrastructure, we managed to run a number of experiments aimed at designing and defining an application specific environment for the simulation software and data sharing. Our successful experiments demonstrate that the gridification of Planck pipelines is not only possible but even extremely convenient in terms of data processing speed and data sharing.

Grid and Databases: BaSTI as a Practical Integration Example

Stellar Astrophysics and in particular stellar evolutionary computations are extremely important to face a wealth of astrophysical problems, but they are also extremely demanding in terms of computing power and data storage. The Bag of Stellar Tracks and Isochrones (BaSTI) database is a theoretical astrophysical catalogue that collects fundamental data sets involving stars formation and evolution. To create this database it is necessary to run a large number of stellar evolutionary computations. The Grid technology seems to be a promising answer to data storage and processing needs of the BaSTI catalogue. In the framework of the EGEE Grid infrastructure, we managed to run a number of experiments aimed at designing and defining an application specific environment for the stellar simulation software and its interaction with the BaSTI database. Our successful implementation demonstrates that the “gridification” of stellar evolution code is not only possible but also even extremely convenient in terms of data processing speed and data sharing, and it can be a valuable instrument to support Astrophysical research.

Interconnecting the Virtual Observatory with computational grid infrastructures

The term ‘grid’, in the Virtual Observatory (VO) context, has mainly been used to indicate a set of interoperable services, allowing transparent access to a set of geographically distributed and heterogeneous archives and catalogues, data exchange and analysis, etc. The design of the VO has been however mainly geared at allowing users to access registered services .

Core-line tracing for fuzzy image subsets

A method allowing core-line tracing for grey-scale images and, in particular, for fuzzy image subsets is proposed. The method is based on the Maximal Square Moving technique, which allows a data-structure-type representation of the medial axis of an image. An application of the method to an astronomical imaging problem is shown.

Creating Gateway Alliances Using WS-PGRADE/gUSE

The STARnet Gateway Federation is a unique example of a federated network of science gateways based on WS-PGRADE/gUSE technologies, and explicitly designed and tuned to the needs of the astronomical and astrophysical (A&A) community in Europe. The use of a federated gateway infrastructure allows scientists to explore new collaboration opportunities and advancing the scientific research activity within A&A. STARnet Gateways share a common authentication system, a distributed computing infrastructure, data archives, portlets, and workflow repositories. Building upon these technologies, a number of challenging applications from different A&A domains have been successfully prototyped and tested.

Instruments in Grid: the Instrument Element

This work is focused on the interoperability aspects between the Grid and the scientific instrumentation. The IE (Instrument Element) makes possible the monitoring and the remote control of any kind of scientific instrumentation, although the test-bed of this first implementation is constituted of telescopes and related astronomical instrumentation. The first implementation of the IE deals with monitoring aspects; astronomers can remotely interface the telescope and related instrumentation and check the telemetric and scientific data when they are acquired. Future releases of the IE will include extensions, so that remote control capabilities will be also covered.

The Grid Data Source Engine Batch Query System

The interest in grid-databases integration has been steadily increasing in recent years and several projects provided different grid middleware components or tools trying to face this challenge. Among them the Grid Data Source Engine is offering native access to relational and non-relational data sources in a grid environment. In this paper we present its asynchronous query mechanism and we focus on the ability of this GSI/VOMS based middleware component to be integrated in workflow management systems.

Sharing data, information, and software for the ESA Planck mission: the IDIS prototype

During all phases of the Planck mission (Design, Development, Operations and Post-operations), it is necessary to guarantee proper information management among many Co-Is, Associates, engineers and technical and scientific staff (the estimated number of participants is over 200), located throughout countries in both Europe and North America. Information concerning the project ranges from instrument information (technical characteristics, reports, configuration control documents, drawings, public communications, etc.), to the analysis of the impact on science implied by specific technical choices. For this purpose, an Integrated Data and Information System (IDIS) will be developed to allow proper intra-Consortium and inter-Consortia information exchange. A set of tools will be provided, maximizing use of Commercial Off-The-Shelf (COTS) or reliable public domain software, to allow distributed collaborative research to be carried out. The general requirements for IDIS and its components have bene defined; the preparation of software requirements and COTS selection is being carried out. A prototype IDIS is expected to be available in spring 2000.