1,721,004 research outputs found
Preference-based Matchmaking of Grid Resources With CP-Nets
Full text linkWe deal with the problem of preference-based matchmaking of computational resources belonging to a grid. We introduce CP–Nets, a recent development in the field of Artificial Intelligence, as a means to deal with user’s preferences in the context of grid scheduling. We discuss CP–Nets from a theoretical perspective and then analyze, qualitatively and quantitatively, their impact on the matchmaking process, with the help of a grid simulator we developed for this purpose. Many different experiments have been setup and carried out, and we report here our main findings and the lessons learnt
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
BioGAT: a Grid Toolkit for Bioinformatics Sequence Alignment
No full textEven though there are many useful tools for sequence alignment such as Blast by NCBI, Fasta by the University of Virginia and Smith-Waterman, by NIST, one of the key issues is that sequence databases are exploding in size, growing at an exponential rate. Grid and parallel computing are crucial techniques to maintain and improve the effectiveness of sequence comparison tools, whereas the Web Services approach may guarantee the interoperability among large collections of programs and data. This work describes BioGAT (Bioinformatics Grid Alignment Tools), a toolkit that offers optimized brokering and a data management system to exploit various bioinformatics alignment tools wrapped as Web Services in a Grid architecture
Advanced Delivery Mechanisms in the GRelC Project
No full textToday many Data Grid applications need to manage and process a very large amount of data distributed across multiple grid nodes. Several applications often access large databases (i.e. protein data banks, in the bioinformatics field) without any data access services taking into account characteristics of either applications or data types. Such applications could improve their performance and quality of results by using efficient, cross-DBMS, specialized and ad hoc implemented data access services. The Grid Relational Catalog Project (GRelC) developed at the CACT/ISUFI Laboratory of the University of Lecce provides a grid-enabled access service for relational and not relational repositories. In this paper we propose some advanced delivery mechanisms developed within the GRelC project, showing up experimental results related to an European testbed
The GRELC Project: Towards GRID-DBMS
No full textSeveral Data Grid applications need to manage a lot of data distributed across heterogeneous and wide spreaded resources and stored in Relational Databases. RDBMSs (Relational Database Management Systems) are not grid enabled (with the notable exception of Oracle), so in order to provide security, transparency, robustness, efficiency and dynamic mechanisms in a Grid environment a new concept can be introduced: the Grid-DBMS. After defining it, we talk about an implementation built on top of the Globus Toolkit: the Grid Relational Catalog Project (GRelC) de veloped at the CACT/ISUFI Laboratory of the University of Lecce. Then we present the basic architecture discussing about its main features and components
ProGenGrid: a Grid-enabled platform for Bioinformatics
No full textIn this paper we describe the ProGenGrid (Proteomics and Genomics Grid) system, developed at the CACT/ISUFI of the University of Lecce which aims at providing a virtual laboratory where e‐scientists can simulate biological experiments, composing existing analysis and visualization tools, monitoring their execution, storing the intermediate and final output and finally, if needed, saving the model of the experiment for updating or reproducing it. The tools that we are considering are software components wrapped as Web Services and composed through a workflow. Since bioinformatics applications need to use high performance machines or a high number of workstations to reduce the computational time, we are exploiting a Grid infrastructure for interconnecting wide‐spread tools and hardware resources. As an example, we are considering some algorithms and tools needed for drug design, providing them as services, through easy to use interfaces such as the Web and Web service interfaces built using the open source gSOAP Toolkit, whereas as Grid middleware we are using the Globus Toolkit 3.2, exploiting some protocols such as GSI and GridFTP
A Grid-enabled Protein Secondary Structure Predictor
No full textWe present an integrated Grid system for the prediction of protein secondary structures, based on the frequent automatic update of proteins in the training set. The predictor model is based on a feed-forward multilayer perceptron (MLP) neural network which is trained with the back-propagation algorithm; the design reuses existing legacy software and exploits novel grid components. The predictor takes into account the evolutionary information found in multiple sequence alignment (MSA); the information is obtained running an optimized parallel version of the PSI-BLAST tool, based on the MPI Master–Worker paradigm. The training set contains proteins of known structure. Using Grid technologies and efficient mechanisms for running the tools and extracting the data, the time needed to train the neural network is dramatically reduced, whereas the results are comparable to a set of well-known predictor tools
ProGenGrid: A Grid Framework for Bioinformatics
No full textImportant issues in bioinformatics are the difficulties for non computer experts to use bioinformatics tools, the transparent access to large biological data sets, and the exploitation of large computing power. Moreover, often such tools and databases are developed by independent groups, so the task of enabling their composition and cooperation is even more difficult. Integrating Computational Grid and Web Services technologies can be a key solution to simplify interaction between bioinformatics tools and biological databases. This paper presents ProGenGrid (Proteomics & Genomics Grid), a distributed and ubiquitous grid environment, accessible through the web, for supporting “in silico” experiments in bioinformatics
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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