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Author Mendez, V.; Amoros, G.; Garcia, F.; Salt, J.
Title Emergent algorithms for replica location and selection in data grid Type Journal Article
Year 2010 Publication (up) Future Generation Computer Systems Abbreviated Journal Futur. Gener. Comp. Syst.
Volume 26 Issue 7 Pages 934-946
Keywords Grid computing; Algorithms; Optimization methods; Artificial intelligence
Abstract Grid infrastructures for e-Science projects are growing in magnitude terms. Improvements in data Grid replication algorithms may be critical in many of these infrastructures. This paper shows a decentralized replica optimization service, providing a general Emergent Artificial Intelligence (EAI) algorithm for the problem definition. Our aim is to set up a theoretical framework for emergent heuristics in Grid environments. Further, we describe two EAI approaches, the Particle Swarm Optimization PSO-Grid Multiswarm Federation and the Ant Colony Optimization ACO-Grid Asynchronous Colonies Optimization replica optimization algorithms, with some examples. We also present extended results with best performance and scalability features for PSO-Grid Multiswarrn Federation.
Address [Mendez Munoz, Victor; Amoros Vicente, Gabriel; Salt Cairols, Jose] CSIC, Grid & E Sci Grp, Inst Fis Corpuscular IFIC, Mixed Inst, E-46071 Valencia, Spain, Email: vmendez@ific.uv.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0167-739x ISBN Medium
Area Expedition Conference
Notes ISI:000279804200004 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 411
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Author Peris, J.B.; Davis, P.; Cuevas, J.M.; Nebot, M.; Sanjuan, R.
Title Distribution of Fitness Effects Caused by Single-Nucleotide Substitutions in Bacteriophage f1 Type Journal Article
Year 2010 Publication (up) Genetics Abbreviated Journal Genetics
Volume 185 Issue 2 Pages 603-U308
Keywords
Abstract Empirical knowledge of the fitness effects of mutations is important for understanding many evolutionary processes, yet this knowledge is often hampered by several sources of measurement error and bias. Most of these problems can be solved using site-directed mutagenesis to engineer single mutations, an approach particularly suited for viruses due to their small genomes. Here, we used this technique to measure the fitness effect of 100 single-nucleotide substitutions in the bacteriophage f1, a filamentous single-strand DNA virus. We found that approximately one-fifth of all mutations are lethal. Viable ones reduced fitness by 11% on average and were accurately described by a log-normal distribution. More than 90% of synonymous substitutions were selectively neutral, while those affecting intergenic regions reduced fitness by 14% on average. Mutations leading to amino acid substitutions had an overall mean deleterious effect of 37%, which increased to 45% for those changing the amino acid polarity. Interestingly, mutations affecting early steps of the infection cycle tended to be more deleterious than those affecting late steps. Finally, we observed at least two beneficial mutations. Our results confirm that high mutational sensitivity is a general property of viruses with small genomes, including RNA and single-strand DNA viruses infecting animals, plants, and bacteria.
Address [Peris, Joan B.; Davis, Paulina; Cuevas, Jose M.; Sanjuan, Rafael] Univ Valencia, Inst Cavanilles Biodiversitat & Biol Evolut, Valencia 46980, Spain, Email: rafael.sanjuan@uv.es
Corporate Author Thesis
Publisher Genetics Soc Am Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0016-6731 ISBN Medium
Area Expedition Conference
Notes ISI:000281905200017 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 383
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Author Blume, M.; Martinez-Moller, A.; Keil, A.; Navab, N.; Rafecas, M.
Title Joint Reconstruction of Image and Motion in Gated Positron Emission Tomography Type Journal Article
Year 2010 Publication (up) IEEE Transactions on Medical Imaging Abbreviated Journal IEEE Trans. Med. Imaging
Volume 29 Issue 11 Pages 1892-1906
Keywords Gating; motion compensation; positron emission tomography (PET); reconstruction
Abstract We present a novel intrinsic method for joint reconstruction of both image and motion in positron emission tomography (PET). Intrinsic motion compensation methods exclusively work on the measured data, without any external motion measurements. Most of these methods separate image from motion estimation: They use deformable image registration/optical flow techniques in order to estimate the motion from individually reconstructed gates. Then, the image is estimated based on this motion information. With these methods, a main problem lies in the motion estimation step, which is based on the noisy gated frames. The more noise is present, the more inaccurate the image registration becomes. As we show both visually and quantitatively, joint reconstruction using a simple deformation field motion model can compete with state-of-the-art image registration methods which use robust multilevel B-spline motion models.
Address [Blume, Moritz; Rafecas, Magdalena] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: moritz.blume@cs.tum.edu
Corporate Author Thesis
Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0278-0062 ISBN Medium
Area Expedition Conference
Notes ISI:000283941800007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 340
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Author Bouhova-Thacker, E.; Kostyukhin, V.; Koffas, T.; Liebig, W.; Limper, M.; Piacquadio, G.N.; Prokofiev, K.; Weiser, C.; Wildauer, A.
Title Expected Performance of Vertex Reconstruction in the ATLAS Experiment at the LHC Type Journal Article
Year 2010 Publication (up) IEEE Transactions on Nuclear Science Abbreviated Journal IEEE Trans. Nucl. Sci.
Volume 57 Issue 2 Pages 760-767
Keywords Data analysis; data reconstruction; high energy physics; pattern recognition; reconstruction algorithms; tracking; vertex detectors
Abstract In the harsh environment of the Large Hadron Collider at CERN (design luminosity of 10(34) cm(-2) s(-1)) efficient reconstruction of vertices is crucial for many physics analyses. Described in this paper is the expected performance of the vertex reconstruction used in the ATLAS experiment. The algorithms for the reconstruction of primary and secondary vertices as well as for finding photon conversions and vertex reconstruction in jets are described. The implementation of vertex algorithms which follows a very modular design based on object-oriented C++ is presented. A user-friendly concept allows event reconstruction and physics analyses to compare and optimize their choice among different vertex reconstruction strategies. The performance of implemented algorithms has been studied on a variety of Monte Carlo samples and results are presented.
Address [Bouhova-Thacker, Eva] Univ Lancaster, Lancaster LA1 4YB, England, Email: bouhova@mail.cern.ch
Corporate Author Thesis
Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-9499 ISBN Medium
Area Expedition Conference
Notes ISI:000276679200006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 260
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Author Belver, D.; Cabanelas, P.; Castro, E.; Garzon, J.A.; Gil, A.; Gonzalez-Diaz, D.; Koenig, W.; Traxler, M.
Title Performance of the Low-Jitter High-Gain/Bandwidth Front-End Electronics of the HADES tRPC Wall Type Journal Article
Year 2010 Publication (up) IEEE Transactions on Nuclear Science Abbreviated Journal IEEE Trans. Nucl. Sci.
Volume 57 Issue 5 Pages 2848-2856
Keywords Charge to width algorithm; fast amplifying and digitizing electronics; front-end electronics; HADES; time of flight; timing RPC
Abstract A front-end electronics (FEE) chain for accurate time measurements has been developed for the new Resistive Plate Chamber (RPC)-based Time-of-Flight (TOF) wall of the High Acceptance Di-Electron Spectrometer (HADES). The wall covers an area of around 8 m(2) divided in 6 sectors. In total, 1122 4-gap timing RPC cells are read-out by 2244 time and charge sensitive channels. The FEE chain consists of 2 custom-made boards: a 4-channel Daughter BOard(DBO) and a 32-channel MotherBOard (MBO). The DBO uses a fast 2 GHz amplifier feeding a dual high-speed discriminator. The time and charge information are encoded, respectively, in the leading edge and the width of an LVDS signal. Each MBO houses up to 8 DBOs providing them regulated voltage supply, threshold values via DACs, test signals and, additionally, routing out a signal proportional to the channel multiplicity needed for a 1st level trigger decision. The MBO delivers LVDS signals to a multi-purpose Trigger Readout Board (TRB) for data acquisition. The FEE allows achieving a system resolution around 75 ps fulfilling comfortably the requirements of the HADES upgrade [1]. The commissioning of the whole RPC wall is finished and the 6 sectors are already mounted in their final position in the HADES spectrometer and ready to take data during the beam-times foreseen for 2010.
Address [Belver, Daniel; Cabanelas, P.; Castro, E.; Garzon, J. A.] Univ Santiago Compostela, LabCAF, Santiago De Compostela 15782, Spain, Email: daniel.belver@usc.es
Corporate Author Thesis
Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0018-9499 ISBN Medium
Area Expedition Conference
Notes ISI:000283440400007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 349
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