10 research outputs found

    Optimizing Tertiary Storage Organization and Access for Spatio-Temporal Datasets

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    We address in this paper data management techniques for efficiently retrieving requested subsets of large datasets stored on mass storage devices. This problem represents a major bottleneck that can negate the benefits of fast networks, because the time to access a subset from a large dataset stored on a mass storage system is much greater that the time to transmit that subset over a network. This paper focuses on very large spatial and temporal datasets generated by simulation programs in the area of climate modeling, but the techniques developed can be applied to other applications that deal with large multidimensional datasets. The main requirement we have addressed is the efficient access of subsets of information contained within much larger datasets, for the purpose of analysis and interactive visualization. We have developed data partitioning techniques that partition datasets into "clusters" based on analysis of data access patterns and storage device characteristics. The goal ..

    An Ontology for Scientific Information in a Grid Environment: the Earth System Grid

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    In the emerging world of Grid Computing, shared computational, data, other distributed resources are becoming available to enable scientific advancement through collaborative research and collaboratories. This paper describes the increasing role of ontologies in the context of Grid Computing for obtaining, comparing and analyzing data. We present ontology entities and a declarative model that provide the outline for an ontology of scientific information. Relationships between concepts are also given. The implementation of some concepts described in this ontology is discussed within the context of the Earth System Grid II (ESG)[1]

    High-performance remote access to climate simulation data: A challenge problem for data grid technologies

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    In numerous scientific disciplines, terabyte and soon petabyte-scale data collections are emerging as critical community resources. A new class of Data Grid infrastructure is required to support management, transport, distributed access to, and analysis of these datasets by potentially thousands of users. Researchers who face this challenge include the Climate Modeling community, which performs long-duration computations accompanied by frequent output of very large files that must be further analyzed. We describe the Earth System Grid prototype, which brings together advanced analysis, replica management, data transfer, request management, and other technologies to support high-performance, interactive analysis of replicated data. We present performance results that demonstrate our ability to manage the location and movement of large datasets from the user’s desktop. We report on experiments conducted over SciNET at SC’2000, where we achieved peak performance of 1.55Gb/s and sustained performance of 512.9Mb/s for data transfers between Texas and California. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage, and that copies bear this notice and the full citation on the first page. To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee

    The Earth System Grid: Supporting the Next Generation of Climate Modeling Research

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    Abstract—Understanding the Earth’s climate system and how it might be changing is a preeminent scientific challenge. Global climate models are used to simulate past, present, and future climates, and experiments are executed continuously on an array of distributed supercomputers. The resulting data archive, spread over several sites, currently contains upwards of one hundred terabytes of simulation data and is growing rapidly. Looking towards mid-decade and beyond, we must anticipate and prepare for distributed climate research data holdings of many petabytes. The Earth System Grid (ESG) is a collaborative interdisciplinary project aimed at addressing the challenge of enabling management, discovery, access, and analysis of these critically important datasets in a distributed and heterogeneous computational environment. The problem is fundamentally a Grid problem. Building upo

    The Earth System Grid Federation : an Open Infrastructure for Access to Distributed Geospatial Data

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    The Earth System Grid Federation (ESGF) is a multi-agency, international collaboration that aims at developing the software infrastructure needed to facilitate and empower the study of climate change on a global scale. The ESGF's architecture employs a system of geographically distributed peer nodes, which are independently administered yet united by the adoption of common federation protocols and application programming interfaces (APIs). The cornerstones of its interoperability are the peer-to-peer messaging that is continuously exchanged among all nodes in the federation; a shared architecture and API for search and discovery; and a security infrastructure based on industry standards (OpenID, SSL, GSI and SAML). The ESGF software is developed collaboratively across institutional boundaries and made available to the community as open source. It has now been adopted by multiple Earth science projects and allows access to petabytes of geophysical data, including the entire model output used for the next international assessment report on climate change (IPCC-AR5) and a suite of satellite observations (obs4MIPs) and reanalysis data sets (ANA4MIPs)

    Phytotherapy in Chronic Prostatitis

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    Chronic prostatitis/chronic pelvic pain syndrome continues to pose a treatment challenge for urologists. Chronic prostatitis is a very common and poorly understood condition with significant impact on quality of life. In recent literature, studies have been conducted with various treatment modalities that include antibiotics, α-blockers, anti-inflammatory agents, and cognitive behavioral interventions such as biofeedback and psychotherapy. Patients have shown interest in phytotherapy as a treatment option with increasing frequency due to lack of efficacy of conventional therapies. However, very little is known about the efficacy of second- and third-line treatments, such as the use of herbal supplements. We review published literature regarding phytotherapy usage for chronic prostatitis. The treatments include Chinese herbs, green tea extract, zinc, cernitin pollen extract (bee pollen), quercetin, saw palmetto (Serenoa repens), and lycopene. © 2009 Current Medicine Group LLC.SCOPUS: re.jinfo:eu-repo/semantics/publishe
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