Resource Discovery (resource + discovery)

Distribution by Scientific Domains

Selected Abstracts

Resource discovery in ant communities: do food type and quantity matter?

1. Omnivorous woodland ant species trade off between the ability to find and behaviourally control food resources. Dominant species can limit the ability of subordinates to harvest certain food items. However, subordinate species, by being faster discoverers, could gain access to such food items by arriving at them first. 2. In this study, we tested the hypothesis that resource-directed discovery occurs in ant communities and that good discoverers preferentially discover high value resources. We did this by measuring time to discovery and the number of discoveries of high and low levels of two resource types, crickets and honey, for species occurring in Texas and Arizona woodland ant communities. 3. Ants discovered resources roughly 10 times faster in Texas than in Arizona. They discovered crickets more rapidly than honey in both communities, but there was no difference in the discovery of different resource levels. We also found that species were not biased in their discovery of different resource types or levels. 4. These results provide indirect evidence that discovery is directed by resource stimuli but that such directedness does not impact interspecific exploitative competition. [source]

Resource discovery and management in computational GRID environments

Alan Bradley
Abstract Corporations are currently using computational GRIDs to improve their operations. Future GRIDs will allow an organization to take advantage of computational GRIDs without having to develop a custom in-house solution. GRID resource providers (GRPs) make resources available on the GRID so that others may subscribe and use these resources. GRPs will allow companies to make use of a range of resources such as processing power or mass storage. However, simply providing resources is not enough to ensure the success of a computational GRID: Access to these resources must be controlled otherwise computational GRIDs will simply evolve to become a victim of their own success, unable to offer a suitable quality of service (QoS) to any user. The task of providing a standard querying mechanism for computational GRID environments (CGE) has already witnessed considerable work from groups such as the Globus project who have delivered the Metacomputing Directory Service (MDS), which provides a means to query devices attached to the GRID. This paper presents a review of existing resource discovery mechanisms within CGE. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Liming Chen
In this paper we propose a distributed knowledge management framework for semantics and knowledge creation, population, and reuse on the grid. Its objective is to evolve the Grid toward the Semantic Grid with the ultimate purpose of facilitating problem solving in e-Science. The framework uses ontology as the conceptual backbone and adopts the service-oriented computing paradigm for information- and knowledge-level computation. We further present a semantics-based approach to problem solving, which exploits the rich semantic information of grid resource descriptions for resource discovery, instantiation, and composition. The framework and approach has been applied to a UK e-Science project,Grid Enabled Engineering Design Search and Optimisation in Engineering (GEODISE). An ontology-enabled problem solving environment (PSE) has been developed in GEODISE to leverage the semantic content of GEODISE resources and the Semantic Grid infrastructure for engineering design. Implementation and initial experimental results are reported. [source]

Efficient resource discovery in self-organized unstructured peer-to-peer networks

Lu Liu
Abstract In unstructured peer-to-peer (P2P) networks, two autonomous peer nodes can be connected if users in those nodes are interested in each other's data. Owing to the similarity between P2P networks and social networks, where peer nodes can be regarded as people and connections can be regarded as relationships, social strategies are useful for improving the performance of resource discovery by self-organizing autonomous peers on unstructured P2P networks. In this paper, we present an efficient social-like peer-to-peer (ESLP) method for resource discovery by mimicking different human behaviours in social networks. ESLP has been simulated in a dynamic environment with a growing number of peer nodes. From the simulation results and analysis, ESLP achieved better performance than current methods. Copyright © 2008 John Wiley & Sons, Ltd. [source]

A peer-to-peer decentralized strategy for resource management in computational Grids

Antonella Di Stefano
Abstract This paper presents a peer-to-peer (P2P) approach for the management, in a computational Grid, of those resources that are featured by numerical quantity and thus characterized by a coefficient of utilization, such as percentage of CPU time, disk space, memory space, etc. The proposed approach exploits spatial computing concepts and models a Grid by means of a flat P2P architecture consisting of nodes connected by an overlay network; such a network topology, together with the quantity of resource available in each node, forms a three-dimensional surface, where valleys correspond to nodes with a large quantity of available resource. In this scenario, this paper proposes an algorithm for resource discovery that is based on navigating such a surface, in search of the deepest valley (global minimum, that is, the best node). The algorithm, which aims at fairly distributing among nodes the quantity of leased resource, is based on some heuristics that mimic the laws of kinematics. Experimental results show the effectiveness of the algorithm. Copyright © 2006 John Wiley & Sons, Ltd. [source]

pyGlobus: a Python interface to the Globus ToolkitÔ

Keith R. Jackson
Developing high-performance, problem-solving environments/applications that allow scientists to easily harness the power of the emerging national-scale ,Grid' infrastructure is currently a difficult task. Although many of the necessary low-level services, e.g. security, resource discovery, remote access to computation/data resource, etc., are available, it can be a challenge to rapidly integrate them into a new application. To address this difficulty we have begun the development of a Python-based high-level interface to the Grid services provided by the Globus Toolkit. In this paper we will explain why rapid application development using Grid services is important, look briefly at a motivating example, and finally look at the design and implementation of the pyGlobus package. Copyright © 2002 John Wiley & Sons, Ltd. [source]

A tree-based approach to matchmaking algorithms for resource discovery

Md. Rafiqul Islam
One of the essential operations in a distributed computing is resource discovery. A resource discovery service provides mechanisms to identify the set of resources capable of satisfying the requirements of a job from a large collection of resources. The matchmaking framework provides a reasonable solution to resource management in a distributed environment; it is composed of four important components as classified advertisement (classad), matchmaker protocol, matchmaking algorithm and claiming protocols. Most of the time required to find a resource depends on the performance of the matchmaking algorithms. A distributed environment introduces a large set of heterogeneous resources which is always changing. The matchmaking algorithms should incorporate with this highly changing environment. In this paper we proposed a fast and efficient searching method for matchmaking algorithms which also deals with resource heterogeneity. The proposed approach reduces the searching time to a linear function from a cubic function proposed by R. Raman, M. Livny, and M. Solomon. We discuss briefly the working principles of the method and compare the experimental results of the proposed matchmaking algorithm with those of the existing algorithm. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Describing online learning content to facilitate resource discovery and sharing:the development of the RU LOM Core

G. E. Krull
Abstract The development of Internet technologies has the ability to provide a new era of easily accessible and personalised learning, facilitated through the flexible deployment of small, reusable pieces of digital learning content over networks. Higher education institutions can share and reuse digital learning resources in order to improve their educational offerings. Descriptive language (known as metadata) is required to facilitate the search and retrieval of learning content. Various research offerings have been proposed to promote interoperable educational metadata. However, current metadata standards cannot accommodate the requirements of every community of users. This paper describes the development of an educational metadata application profile for describing learning resources within a South African higher education context. [source]

Generalized MPLS-based distributed control architecture for automatically switched transport networks

Yangguang Xu
Current circuit-switched transport networks, such as plesiochronous digital hierarchy (PDH) and synchronous optical network/synchronous digital hierarchy (SONET/SDH), have traditionally used centralized network management for connection control. To facilitate the value-added capabilities of today's networks,such as the rapid provisioning of services, dynamic setup of bandwidth requests, and fast mesh-based restoration,distributed connection control using signaling protocols has quickly gained industry momentum. Efforts have been initiated in various standards bodies to define the automatically switched transport network (ASTN). Although many architectural choices are now available, this paper describes a distributed control plane architecture that can be applied to various circuit-switching technologies and different network applications. This architecture adopts the concept of a generalized version of multiprotocol label switching (MPLS), which extends and modifies MPLS and other protocols on the Internet to make them applicable to various transport networks and also facilitates optical data networking. Four major functional components are incorporated in this architecture: element-level resource discovery, state information dissemination, path selection, and path control modules. Using these concepts, the transport network can be viewed as a virtual nonblocking, reconfigurable backplane of different network clients. This view represents a radical departure from the traditional data networking view of transport networks as providing fixed pipes and will have a dramatic impact on future network interworking and end-to-end traffic engineering (TE). [source]