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Application Requirements (application + requirement)
Selected AbstractsScience gateways made easy: the In-VIGO approachCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 6 2007Andréa M. Matsunaga Abstract Science gateways require the easy enabling of legacy scientific applications on computing Grids and the generation of user-friendly interfaces that hide the complexity of the Grid from the user. This paper presents the In-VIGO approach to the creation and management of science gateways. First, we discuss the virtualization of machines, networks and data to facilitate the dynamic creation of secure execution environments that meet application requirements. Then we discuss the virtualization of applications, i.e. the execution on shared resources of multiple isolated application instances with customized behavior, in the context of In-VIGO. A Virtual Application Service (VAS) architecture for automatically generating, customizing, deploying, and using virtual applications as Grid services is then described. Starting with a grammar-based description of the command-line syntax, the automated process generates the VAS description and the VAS implementation (code for application encapsulation and data binding) that is deployed and made available through a Web interface. A VAS can be customized on a per-user basis by restricting the capabilities of the original application or by adding to it features such as parameter sweeping. This is a scalable approach to the integration of scientific applications as services into Grids and can be applied to any tool with an arbitrarily complex command-line syntax. Copyright © 2006 John Wiley & Sons, Ltd. [source] A performance comparison between the Earth Simulator and other terascale systems on a characteristic ASCI workload,CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 10 2005Darren J. Kerbyson Abstract This work gives a detailed analysis of the relative performance of the recently installed Earth Simulator and the next top four systems in the Top500 list using predictive performance models. The Earth Simulator uses vector processing nodes interconnected using a single-stage, cross-bar network, whereas the next top four systems are built using commodity based superscalar microprocessors and interconnection networks. The performance that can be achieved results from an interplay of system characteristics, application requirements and scalability behavior. Detailed performance models are used here to predict the performance of two codes representative of the ASCI workload, namely SAGE and Sweep3D. The performance models encapsulate fully the behavior of these codes and have been previously validated on many large-scale systems. One result of this analysis is to size systems, built from the same nodes and networks as those in the top five, that will have the same performance as the Earth Simulator. In particular, the largest ASCI machine, ASCI Q, is expected to achieve a similar performance to the Earth Simulator on the representative workload. Published in 2005 by John Wiley & Sons, Ltd. [source] Microfluidic chip-capillary electrophoresis for two orders extension of adjustable upper working range for profiling of inorganic and organic anions in urineELECTROPHORESIS, Issue 18 2010Wen Peng Guo Abstract To meet the need for onsite monitoring of urine anions, a microfluidic chip-capillary electrophoresis device was designed, fabricated and tested to extend the upper CE working range for an enhancement up to 500 fold (100 fold for sample dilution and 5 folds for CE injection) in order to analyze highly variable anionic metabolites in urine samples. Capillaries were embedded between two PMMA plates with laser-fabricated microchannel patterns to produce the microfluidic chip-capillary electrophoresis to perform standard/sample dilution and CE injection with adjustable dilution ratios. A circular ferrofluid valve was incorporated on-chip to perform cleanup and conditioning, mixing and dilution, injection and CE separation. Under optimized conditions, a complete assay for four samples can be achieved within an hour for 15 anions commonly found in urines. Satisfactory working ranges (0.005,500,mM) and low detection limits (0.5,6.5,,M based on S/N =2) are obtained with satisfactory repeatability (RSD, n=5) 0.52,0.87% and 4.1,6.5% for migration time and peak area, respectively. The working ranges with two orders adjustable upper extension are adequate to cover all analytes concentrations commonly found in human urine samples. The device fabricated shows sufficiently large experimentally verifiable enhancement factor to meet the application requirements. Its reliability was established by more than 94% recoveries of spiked standards and agreeable results from parallel method comparison with conventional ion chromatography method. The extension of the upper CE working range enables flexible onsite dilution on demand, a quick turn-around of results, and a low-cost device suitable for bedside monitoring of patients under critical conditions for metabolic disorders. [source] Cross-layer protocol optimization for satellite communications networks: a surveyINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 5 2006Giovanni Giambene Abstract Satellite links are expected to be one important component of the next-generation Internet. New satellite system architectures are being envisaged to be fully IP based and support digital video broadcasting and return channel protocols (e.g. DVB-S, DVB-S2 and DVB-RCS). To make the upcoming satellite network systems fully realizable, meeting new services and application requirements, a complete system optimization is needed spanning the different layers of the OSI, and TCP/IP protocol stack. This paper deals with the cross-layer approach to be adopted in novel satellite systems and architectures. Different cross-layer techniques will be discussed, addressing the interactions among application, transport, MAC and physical layers. The impacts of these techniques will be investigated and numerical examples dealing with the joint optimization of different transport control schemes and lower layers will be considered referring to a geostationary-based architecture. Our aim is to prove that the interaction of different layers can permit to improve the higher-layer goodput as well as user satisfaction. Copyright © 2006 John Wiley & Sons, Ltd. [source] Transport protocols in multicast via satelliteINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 6 2004Gun Akkor Abstract In a wide variety of broadband applications, there is a need to distribute information to a potentially large number of receiver sites that are widely dispersed from each other. Communication satellites are a natural technology option and are extremely well suited for carrying such services because of the inherent broadcast capability of the satellite channel. Despite the potential of satellite multicast, there exists little support for multicast services over satellite networks. Although several multicast protocols have been proposed for use over the Internet, they are not optimized for satellite networks. One of the key multicast components that is affected when satellite networks are involved in the communication is the transport layer. In this paper, we attempt to provide an overview of the design space and the ways in which the network deployment and application requirements affect the solution space for transport layer schemes in a satellite environment. We also highlight some of the issues that are critical in the development of next generation satellite multicast services. Copyright © 2004 John Wiley & Sons, Ltd. [source] Quality of service for satellite IP networks: a surveyINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 4-5 2003Sastri Kota Abstract The future media rich applications such as media streaming, content delivery distribution and broadband access require a network infrastructure that offers greater bandwidth and service level guarantees. As the demand for new applications increases, ,best effort' service is inadequate and results in lack of user satisfaction. End-to-end quality of service (QoS) requires the functional co-operation of all network layers. To meet future application requirements, satellite is an excellent candidate due to features such as global coverage, bandwidth flexibility, broadcast, multicast and reliability. At each layer, the user performance requirements should be achieved by implementation of efficient bandwidth allocation algorithms and satellite link impairment mitigation techniques. In this paper, a QoS framework for satellite IP networks including requirements, objectives and mechanisms are described. To fully understand end-to-end QoS at each layer, QoS parameters and the current research are surveyed. For example at physical layer (modulation, adaptive coding), link layer (bandwidth allocation), network layer (IntServ/DiffServ, MPLS traffic engineering), transport layer (TCP enhancements, and alternative transport protocols) and security issues are discussed. Some planned system examples, QoS simulations and experimental results are provided. The paper also includes the current status of the standardization of satellite IP by ETSI, ITU and IETF organizations. Copyright © 2003 John Wiley & Sons, Ltd. [source] Control of composition and structure of ferroelectric oxide thin films grown by pulsed laser depositionPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 10 2008Maryline Guilloux-Viry Abstract SrBi2Nb2O9 and KTa1,xNbxO3 high quality thin films were grown by pulsed laser deposition. An accurate optimization of deposition conditions is a prerequisite for the control of composition, mainly according to the high volatility of Bi and K. In order to take benefit of the ferroelectric characteristics for new microelectronic devices, thin films were epitaxially grown on various substrates and seed layers adapted to application requirements. For that purpose metal electrodes and ferroelectric oxides were associated in a planar capacitor geometry or in a coplanar configuration depending on the targeted applications. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Flexible routing in a distributed K -ary tree: the K -UmbrellaEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 2 2009Athanasios-Dimitrios Sotiriou As peer-to-peer (P2P) applications become more mature and demanding, there is a need for the underlying technologies to provide more adaptive characteristics, according to the application's requirements. In this paper, we present K -Umbrella, a K -ary distributed hash table (DHT), which allows us to efficiently route through the use of a fixed-size routing table. By controlling a number of parameters, our algorithm is able to trade-off between efficiency, fault-tolerance and decentralisation according to the application's requirements. Through a detailed analysis of our algorithms and an extensive set of simulations, we will show that our protocol is able to offer an improved alternative to current DHT algorithms. Copyright © 2007 John Wiley & Sons, Ltd. [source] Active resource management for the differentiated services environmentINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 3 2004Manish Mahajan This paper presents a mechanism for active resource management (ARM) in a differentiated services environment. While the differentiated services architecture and the bandwidth broker agent provide a mechanism for QoS management through resource reservation, this mechanism is based on a static provisioning of resources. As bandwidth requirement are typically dynamic, such a static reservation approach can either lead to wasted bandwidth or leave applications resource-starved. The active resource management approach presented in this paper addresses this problem by dynamically reallocating resources based on current network state and applications requirements. An implementation and evaluation of ARM using the NS-2 simulation toolkit is also presented.,Copyright © 2004 John Wiley & Sons, Ltd. [source] | |||||||||||||