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The data management problems in grid computing are often challenging in many aspects such as data volumes, heterogeneity, structural complexity and semantic content. Thus, e-Scientists and scientific application developers stand to benefit from tools and environments that either hide, or help to manage, the inherent complexity involved in accessing and making concerted use of the diverse resources. This paper describes OGSA-DQP, a high level data integration tool for service-based grids, and illustrates how it can be used to support grid users, via an example scientific study in bioinformatics. The paper also discusses various options for employing OGSA-DQP to handle data integration tasks as service orchestrations involving both data and analysis services. [ABSTRACT FROM AUTHOR]

Intelligent Transportation System (ITS) refers to the use of information technologies to address and alleviate transportation problems. The challenges of ITS exist mainly in synthesizing information from geographically distributed, dynamic and heterogeneous databases, specialized sensors and other systems. This synthesis process is computation and communication intensive. Computational Grid is a promising platform for such large-scale data-intensive applications. Building on grid computing technologies, this paper presents a novel infrastructure referred to as Traffic Information Grid (TIG) for ITS development and deployment. The service-oriented and layered system architecture of TIG is introduced and described. Two implementation modes-request/response mode and subscribe/notify mode are presented and evaluated with real traffic data respectively. In addition, an example application is given to illustrate how the TIG works. Based on the practice of TIG, Grid computing is proved to be an effective solution for data-intensive applications. [ABSTRACT FROM AUTHOR]

The Semantic Grid is an extension of the current Grid in which information will be given well-defined meaning, better enabling computers and resources to work in cooperation and coordination. The architecture of Semantic Grid adopts a service-oriented perspective in which distinct entities are represented as software agents, provide services to one another. Traditionally Grid management frameworks are based upon fixed management functionality and fixed interaction interfaces that cannot satisfy the flexibility and complexity that the dynamic Semantic Resource Grid demands. Agent technology is promising in this domain since it facilitates automatic negotiation of services contracts a dynamic configuration of those services, thus enhancing the provisioning for semantic grid services. In this paper we propose an infrastructure for resource monitoring and management in Semantic resource Grid. Our architecture unifies sharing and managing of heterogeneous resources across the Grid. The resources will be able to actively find and advertise services. The resources will be arranged into groups which will enable the resource to have common understanding. We used agents in our architecture which enable the resources to have effective negotiation, support dynamic services and services utilization and advertisement. In this way we can achieve self-controllability and self-coordinability among Grid resource. We argue that semantics is a key to autonomy of the operation and management in emerging complex dynamic systems, such as Semantic Grid. Our architecture could be a part of resource monitoring and management middleware in the Semantic Resource Grid. [ABSTRACT FROM AUTHOR]

Grid technologies enable the sharing and coordinated use of diverse resources distributed all over the world. These resources are owned by different organizations having different policies and objectives which need to be considered in making the resource allocation decisions. In such complex environments market-based resource allocation protocols are a better alternative to the classical ones because they take into consideration the policies and preferences of both users and resource owners. The only suitable solution for investigating the effectiveness of these resource allocation protocols over a wide range of scenarios with reproducible results is to consider simulations. Thus in this paper we present Mercatus, a simulation toolkit that facilitates the simulation of market-based resource allocation protocols. We describe the model and the structure of Mercatus and present experimental results obtained by simulating three types of auction-based resource allocation protocols. [ABSTRACT FROM AUTHOR]

In this paper, we propose an architecture of accounting and payment services for service-oriented grid computing systems. The proposed accounting and payment services provide the mechanisms for service providers to be paid for authorized use of their resources. It supports the recording of usage data, secure storage of that data, analysis of that data for purposes of billing and so forth. It allows a variety of payment methods, it is scalable, secure, convenient, and reduce the overall cost of payment processing while taking into account requirements of Grid computing systems. [ABSTRACT FROM AUTHOR]

In this paper, we present a new extension and reinterpretation of one of the most successful models of awareness in Computer Supported Cooperative Work (CSCW), called the Spatial Model of Interaction (SMI), which manages awareness in Collaborative Virtual Environments (CVEs) through a set of key concepts. This work, carried out at the Universidad Politécnica de Madrid, proposes a couple of special features: the management of the data information from the user point of view and the co-ordinated sharing of computational resources in a virtual organisation. The final awareness model allows users to be aware of the data grid information in a grid computing infrastructure. [ABSTRACT FROM AUTHOR]

Many model-based fault diagnosis approaches have been proposed so far and some of them have been put into industrial practices. But for modern complex processes, due to the variable nature of faults and model uncertainty, no single approach can diagnose all faults and meet different contradictory criteria. In this paper, the importance of integration of different fault diagnostic schemes in a common framework is emphasised. A service-oriented architecture for the integration is proposed based on Grid technologies. As an implementation, a decision support system for the gas turbine engine fault diagnosis is presented and some deployed services are discussed. [ABSTRACT FROM AUTHOR]

The paper is concerned with supporting natural patterns of scientific collaboration in Access Grid environments. We reveal that no current approach to Access Grid allows dynamic session invocation within on-going Access Grid sessions nor workflow driven session triggering among users involved in that workflow. A model for a lightweight signaling architecture integrated within Access Grid is proposed that allows transparent demand-driven session management. The architecture is configurable both in terms of dynamically changing user preferences and resource requirements. The core of the architecture is the advanced SIP stack embedded both within Access Grid nodes and heterogenous end nodes. This is important in order to allow maximum flexibility of audio,video and workflow presentation to the end users. Keywords: Access Grid, P2P, SIP, Video Conferencing. [ABSTRACT FROM AUTHOR]

Grids constitute a promising platform to execute loosely coupled applications, which arise naturally in many scientific and engineering fields like bioinformatics, computational fluid dynamics, particle physics, etc. In this paper, we describe our experiences in porting three scientific production codes to the Grid. Those codes follow typical computational models, namely: embarrassingly distributed and master-worker. In spite of their relatively simple computational structure, consisting of many "independent" tasks, their reliable and efficient execution on computational Grids involves several issues, due to both the dynamic nature of the Grid itself and the execution and programming requirements of the applications. The applications have been developed by using the DRMAA (Distributed Resource Management Application API) interface. DRMAA routines are supported by the functionality offered by the GridWay framework, that provides the runtime mechanisms needed for transparently executing jobs on a dynamic Grid environment. The experiments have been performed on Globus-based research testbeds that span heterogeneous resources in different institutions. [ABSTRACT FROM AUTHOR]

This paper describes the design and implementation of a model of how to integrate sensors and devices into a Grid infrastructure. We describe its proxy-based approach, the port-type requirements and the set of tools implemented to facilitate configuration of experimental scenarios. Two real world devices, a wearable medical jacket and an Antarctic lake probe, deployed out in the field using this architecture are described, along with their relevance in scientific research. [ABSTRACT FROM AUTHOR]

This paper describes the increasing role of ontologies in the context of Grid computing for obtaining, comparing and analyzing distributed heterogeneous scientific data. In the communities of people committed to a common goal, the management of resources and services becomes very important. We chose the application domain of human disease research and control. A characteristic of the domain is that trusted databases exist but their schemas are often poorly or not documented. The network of biomedical databases forms a loose federation of autonomous, distributed, heterogeneous data repositories ripe for information integration. Grid services will provide a dynamic way to use resources in such a large distributed scientific environment while the use of ontology enables the system to carryout reasoning at 3 levels: a) available information in all Bio-Databases (Grid nodes) worldwide, b) reasoning about the retrievable information from each node, c) reasoning about the retrieved information and presenting it in a meaningful format for users. We adopted the ontology design methodology of DOGMA and developed Generic Human Disease Ontology (GenDO) that contains common general information regarding human diseases. The information is represented in 4 "dimensions": (a) disease types, (b) causes (c) symptoms and (d) treatments. We illustrate how this GenDO helps to produce Specific Human Disease Ontologies (SpeDO) on request. We show how the combination of two different but complementary techniques, namely Grid computing and ontology, results in a dynamic and intelligent information system. The two approaches together, being complementary, enable the system as a whole. [ABSTRACT FROM AUTHOR]

Most works on Grids have taken an approach where the system is a mixture of clusters and other resources put together with the help of some services. But this solution is a simplistic one that tries to grow from the cluster perspective. We think that the Grid model should be different and near to the p2p model, especially in the I/O field where the network and the heterogeneity of the infrastructure play an important role. In this paper we present a model to organize the DataGrid Infrastructure using concepts as data phases and a p2p approach, in order to select the adequate working policies. These concepts allow the definition of a clearer model for our DataGrid Architecture than a mixture of resources. We present a model relying on the former concepts, their implementation in an I/O middleware for Grids, called GridExpand, and the evaluation of some of the concepts presented. [ABSTRACT FROM AUTHOR]

One of the major advantages of Grid Computing (GC) technology is the use of geographically distributed resources. Nevertheless, just like any kind of systems, GC environments have a great problem: I/O system is the bottleneck of the whole system. In order to obtain a better performance, it is necessary and advisable to improve the data access. This problem could be solved by introducing a parallel data access to grid resources. Since GC consists of many resources and some of them are clusters, it would be possible to exploit the parallelism among the different nodes of each cluster. We propose to use two levels of parallelism in a Grid environment to improve the data access and therefore the whole system performance. The low level will be represented by the nodes of each cluster, and the high level will include all the clusters. This paper shows a new architecture for grids, which is based on the parallel file system MAPFS, designed for high performance clusters. Keywords: Grid Computing (GC), Grid Services (GS), parallel I/O systems, Grid Architecture. [ABSTRACT FROM AUTHOR]

In today's large collaborative environments, potentially composed of multiple distinct organisations, uniform controlled access to data has become a key requirement if these organisations are to work together as Virtual Organisations. We refer to such an integrated set of data resourcesA data resource here is taken to mean any entity that can act as a source and/or sink of data together with its associated management framework. Although the framework being developed at the moment works mainly with databases the scope is more general and could encompass file systems and streams. as a virtual data warehouse. The Open Grid Services Architecture - Data Access and Integration (OGSA-DAI) project was established to produce a common middleware solution, aligned with the Global Grid Forum's (GGF) OGSA vision [OGSA] to allow uniform access to data resources using a service based architecture. In this paper the service infrastructure provided by OGSA-DAI is presented providing a snapshot of its current state, in an evolutionary process, which is attempting to build infrastructure to allow easy integration and access to distributed data using grids or web services. More information about OGSA-DAI is available from the project web site: www.ogsadai.org. Keywords: Data, Databases, Grid, DAIS, OGSA-DAI, Open Grid Services Architecture, Web Services. [ABSTRACT FROM AUTHOR]