IT Innovation

Recent developments at the UK National Crystallography Service (NCS), in collaboration with the CombeChem eScience testbed and the eBank-UK projects, have been aimed at developing an eScience infrastructure to facilitate the crystallographic experiment from end to end. A seamless distributed computing approach is shown to be able to transform a conventional but high throughput service, to enable access and secure remote operation with the visualisation of the diffraction experiment, through the data workup and analysis ...

Executive Summary This document describes the result of WP5. 3 activity in the first 12 months concerning modelling and management of adaptive workflows and dynamic service orchestration. Activity was mainly focused on defining a Semantic Workflow Representation Model and Language to enable different kind of users in representing workflows at different architectural levels, eg application and business process. The Language Workflow Model was developed and integrated within an Enactment Model aimed at evaluating abstract ...

As the technical infrastructure to support Grid environments matures, attention must be focused on integrating such technical infrastructure with technologies to support more dynamic access to services, and ensuring that such access is appropriately monitored and secured. Current approaches for securing organisations thorugh conventional firewalls are insufficient; access is either enabled or disabled for a given port, whereas access to Grid services may be conditional on dynamic factors. This paper reports on the Semantic Firewall (SFW) project, which investigated a policy-based security mechanism responsible for mediating interactions with protected services given a set of dynamic access policies, which define the conditions in which access may be granted to services. The aims of the project are presented, and results and contributions described.

The EU IST SIMDAT project is developing generic Grid technology targeted at business users from several representative industry sectors. We have developed an SLA (Service Level Agreement) Management service for GRIA middleware that allows service ...

The ARTEMIS project is developing a semantic web service based P2P interoperability infrastructure for healthcare information systems that will allow healthcare providers to securely share patient records within virtual healthcare organisations. ...

Performance engineering can be described as a collection of techniques and methodologies whose aim is to provide reliable prediction, measurement and validation of the performance of applications on a variety of computing platforms. This paper reviews techniques for performance estimation and performance engineering developed at the University of Southampton and presents application case studies in task scheduling for engineering meta-applications, and capacity engineering for a financial transaction processing system. These show that it is important to describe performance in terms of a resource model, and that the choice of models may have to trade accuracy for utility in addressing the operational issues. We then present work from the on-going EU funded Grid project GRIA, and show how lessons learned from the earlier work have been applied to support a viable business model for Grid service delivery to a specified quality of service level. The key in this case is to accept the limitations of performance estimation methods, and design business models that take these limitations into account rather than attempting to provide hard guarantees over performance. We conclude by identifying some of the key lessons learned in the course of our work over many years and suggest possible directions for future investigations. Copyright

A candidate model for Grand Unification, arising from a Coset Space Dimensional Reduction scheme based on an E(7) gauge theory, is found to have a promising set of fermionic quantum numbers. Unfortunately, these fermions all develop large (geometric) masses. We derive formulae for the square of the Dirac operator and for fermion masses for a large class of CSDR schemes, revealing this as a general feature.

This paper defines meta-applications as large, related collections of computational tasks, designed to achieve a specific overall result, running on a (possibly geographically) distributed, non-dedicated meta-computing platform. To carry out such applications in an industrial context, one requires resource management and job scheduling facilities (including capacity planning), to ensure that the application is feasible using the available resources, that each component job will be sent to an appropriate resource, and that everything will finish before the computing resources are needed for other purposes.

An application of e-science methodology and grid networking technology is presented that opens up new possibilities to enhance the operation of large high-throughput service-crystallography facilities, exemplified by the UK National Crystallography Service (NCS). A seamless distributed computing approach is used to provide remote secure visualization, monitoring and interaction with the laboratory and the diffraction experiment, supervision and input to the data workup and analysis processes, and to enable dissemination and further use of the resulting structural data. The architecture of the system is based on web and grid services (in particular the use ofGlobus, v1.1.4), which provide a secure environment for two-way information flow and communication between the service users and operators. This capability will enhance operations of instrument and software automation by providing more efficient use of the resources, increasing the throughput of samples and enabling interactions ...

The GEMSS project has developed a service-oriented Grid that supports the provision of medical simulation services by service providers to clients such as hospitals. We outline the GEMSS architecture, legal framework and the security features that characterise the GEMSS infrastructure. High levels of quality of service are required and we describe a reservation-based approach to quality of service, employing a quality of service management system that iteratively finds suitable reservations and uses application specific performance models. The GEMSS Grid is a commercial environment so we support flexible pricing models and a FIPA reverse English auction protocol. Signed Web Service Level Agreement contracts are exchanged to commit parties to a quality of service agreement before job execution occurs. We run four experiments across European countries using high performance computing resources running advanced resource reservation schedulers. These experiments provide evidence for our Grid's rational behaviour, both at the level of service provider quality of service management and at the higher level of the client choosing between competing service providers. The results lend support to our economic model and the technology we use for our medical application domain.

We consider bosonic extensions of the Virasoro algebra that can be obtained from Kac-Moody algebras ~ by generalizing the Sugawara construction to the higher order Casimirs of g. In this paper we explicitly construct the algebra of a primary field of dimension 3 constructed from the 3rd order Casimir of A s 1. For N = 3 we compare our results to the Z3-extended Virasoro algebra proposed by Fateev and Zamolodchikov.

We discuss extensions of the Virasoro algebra obtained by generalizing the Sugawara construction to the higher order Casimir invariants of a Lie algebra g. We generalize the GKO coset construction to the dimension-3 operator for g =A N 1 and recover results of Fateev and Zamolodchikov if N = 3. Branching rules and generalizations to all simple, simply-laced g are discussed.

A new model for calculating electron beam dose has been developed. The algorithm is based on a two-or three-dimensional geometry, given by computerized tomography (CT) images. The Monte Carlo technique was used to solve the electron transport equation. The model takes into account basic processes like continuos energy loss, multiple elastic scattering, delta particle and bremsstrahlung production. However, in contrast to conventional Monte Carlo models (EGS4) several approximations and simplifications in the description of elementary electron processes were introduced reducing in this manner the computational time by a factor of about 35 without loss of accuracy. The Monte Carlo computer program does not need any precalculated data. The random access memory required depending on the resolution of the CT cube is about 16 Mbytes for a 128 2 x 50 matrix. At first, the Voxel Monte Carlo model (VMC) was tested in comparison to calculations by EGS4 and the "3D-Hogstrom algorithm" (MDAH) using several fictive phantoms. In all cases it has been found a good coincidence between EGS4 and VMC, especially near tissue inhomogeneities, whereas the MDAH algorithm has produced dose underestimations of up to 40 %. In a second step measurements were performed using a water phantom with defined inhomogeneities consisting of e.g. aluminium. A comparison of the measured profiles and depth dose curves to calculations by VMC shows, that the model describes the electron transport in the patient correctly. The largest deviations found are in the order of 2 %.

As the technical infrastructure to support Grid environments matures, attention must be focused on integrating such technical infrastructure with technologies to support more dynamic access to services, and ensuring that such access is appropriately monitored and secured. Such capabilities will be key in providing a safe environment that allow the creation of virtual organisations at runtime. This paper addresses this issue by analysing how work from within the field of Electronic Institutions (EIs) can be employed to provide security support for Grid environments, and introduces the notion of a Semantic Firewall (SFW) responsible for mediating interactions with protected services given a set of access policies. An overarching guideline is that such integration should be pragmatic, taking into account the real-life lessons learned whilst developing, deploying and using the GRIA infrastructure for Grid environments.