941 resultados para open source seismic data processing packages


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Seafloor imagery is a rich source of data for the study of biological and geological processes. Among several applications, still images of the ocean floor can be used to build image composites referred to as photo-mosaics. Photo-mosaics provide a wide-area visual representation of the benthos, and enable applications as diverse as geological surveys, mapping and detection of temporal changes in the morphology of biodiversity. We present an approach for creating globally aligned photo-mosaics using 3D position estimates provided by navigation sensors available in deep water surveys. Without image registration, such navigation data does not provide enough accuracy to produce useful composite images. Results from a challenging data set of the Lucky Strike vent field at the Mid Atlantic Ridge are reported

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Nowadays, when a user is planning a touristic route is very difficult to find out which are the best places to visit. The user has to choose considering his/her preferences due to the great quantity of information it is possible to find in the web and taking into account it is necessary to do a selection, within small time because there is a limited time to do a trip. In Itiner@ project, we aim to implement Semantic Web technology combined with Geographic Information Systems in order to offer personalized touristic routes around a region based on user preferences and time situation. Using ontologies it is possible to link, structure, share data and obtain the result more suitable for user's preferences and actual situation with less time and more precisely than without ontologies. To achieve these objectives we propose a web page combining a GIS server and a touristic ontology. As a step further, we also study how to extend this technology on mobile devices due to the raising interest and technological progress of these devices and location-based services, which allows the user to have all the route information on the hand when he/she does a touristic trip. We design a little application in order to apply the combination of GIS and Semantic Web in a mobile device.

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Engineering of negotiation model allows to develop effective heuristic for business intelligence. Digital ecosystems demand open negotiation models. To define in advance effective heuristics is not compliant with the requirement of openness. The new challenge is to develop business intelligence in advance exploiting an adaptive approach. The idea is to learn business strategy once new negotiation model rise in the e-market arena. In this paper we present how recommendation technology may be deployed in an open negotiation environment where the interaction protocol models are not known in advance. The solution we propose is delivered as part of the ONE Platform, open source software that implements a fully distributed open environment for business negotiation

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BACKGROUND: Solexa/Illumina short-read ultra-high throughput DNA sequencing technology produces millions of short tags (up to 36 bases) by parallel sequencing-by-synthesis of DNA colonies. The processing and statistical analysis of such high-throughput data poses new challenges; currently a fair proportion of the tags are routinely discarded due to an inability to match them to a reference sequence, thereby reducing the effective throughput of the technology. RESULTS: We propose a novel base calling algorithm using model-based clustering and probability theory to identify ambiguous bases and code them with IUPAC symbols. We also select optimal sub-tags using a score based on information content to remove uncertain bases towards the ends of the reads. CONCLUSION: We show that the method improves genome coverage and number of usable tags as compared with Solexa's data processing pipeline by an average of 15%. An R package is provided which allows fast and accurate base calling of Solexa's fluorescence intensity files and the production of informative diagnostic plots.

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El projecte se centra en el la vall d’Alinyà, en els terrenys de la Fundació Territori i Paisatge que abasten des dels cims del Port del Comte, a més de 2.000 m d’altitud fins més avall del nucli de Perles en els 500 m, en un ambient de muntanya a la comarca de l’Alt Urgell, Catalunya. L’objectiu principal ha estat diagnosticar la situació de la ramaderia extensiva de la vall, tot predient la seva viabilitat socioeconòmica com a estratègia de futur, tant pel que fa la seva població, com per les característiques d’un paisatge en mosaic molt ben afaiçonat per la mà humana en el passat. Aquesta diversitat paisatgística assegurada per l’existència de la ramaderia extensiva, provoca una riquesa en biodiversitat ecològica, en front del creixement continu de la massa forestal causat per l’abandonament de les activitats a la muntanya. Un dels aspectes estudiats de la ramaderia de la vall, ha estat la gestió dels cinc ramats existents en l’actualitat, dos de vaques, un de cabres, un d’ovelles i un de cavalls. Des de la identificació dels moviments de transtermitància durant les diferents estacions de l’any, a la de l’obtenció dels diferents recursos alimentaris pel bestiar provinents directament de la natura. Les entrevistes personals als ramaders han estat una important font d’informació i de tractament de dades per poder diagnosticar la situació actual del sector i de la figura del pastor com a figura professional clau en la vessant socioeconòmica i paisatgística local. Es van poder identificar clarament els problemes amb els quals es troba la ramaderia extensiva i quins reptes presenta per poder arribar a ser un sector de futur per a la població de la vall. En aquest context es proposen mesures de millora de l’activitat i de difusió dels productes agroramaders de qualitat.

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Using a numerical approach, we explore wave-induced fluid flow effects in partially saturated porous rocks in which the gas-water saturation patterns are governed by mesoscopic heterogeneities associated with the dry frame properties. The link between the dry frame properties and the gas saturation is defined by the assumption of capillary pressure equilibrium, which in the presence of heterogeneity implies that neighbouring regions can exhibit different levels of saturation. To determine the equivalent attenuation and phase velocity of the synthetic rock samples considered in this study, we apply a numerical upscaling procedure, which permits to take into account mesoscopic heterogeneities associated with the dry frame properties as well as spatially continuous variations of the pore fluid properties. The multiscale nature of the fluid saturation is taken into account by locally computing the physical properties of an effective fluid, which are then used for the larger-scale simulations. We consider two sets of numerical experiments to analyse such effects in heterogeneous partially saturated porous media, where the saturation field is determined by variations in porosity and clay content, respectively. In both cases we also evaluate the seismic responses of corresponding binary, patchy-type saturation patterns. Our results indicate that significant attenuation and modest velocity dispersion effects take place in this kind of media for both binary patchy-type and spatially continuous gas saturation patterns and in particular in the presence of relatively small amounts of gas. The numerical experiments also show that the nature of the gas distribution patterns is a critical parameter controlling the seismic responses of these environments, since attenuation and velocity dispersion effects are much more significant and occur over a broader saturation range for binary patchy-type gas-water distributions. This analysis therefore suggests that the physical mechanisms governing partial saturation should be accounted for when analysing seismic data in a poroelastic framework. In this context, heterogeneities associated with the dry frame properties, which do not play important roles in wave-induced fluid flow processes per se, should be taken into account since they may determine the kind of gas distribution pattern taking place in the porous rock.

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The Computational Biophysics Group at the Universitat Pompeu Fabra (GRIB-UPF) hosts two unique computational resources dedicated to the execution of large scale molecular dynamics (MD) simulations: (a) the ACMD molecular-dynamics software, used on standard personal computers with graphical processing units (GPUs); and (b) the GPUGRID. net computing network, supported by users distributed worldwide that volunteer GPUs for biomedical research. We leveraged these resources and developed studies, protocols and open-source software to elucidate energetics and pathways of a number of biomolecular systems, with a special focus on flexible proteins with many degrees of freedom. First, we characterized ion permeation through the bactericidal model protein Gramicidin A conducting one of the largest studies to date with the steered MD biasing methodology. Next, we addressed an open problem in structural biology, the determination of drug-protein association kinetics; we reconstructed the binding free energy, association, and dissaciociation rates of a drug like model system through a spatial decomposition and a Makov-chain analysis. The work was published in the Proceedings of the National Academy of Sciences and become one of the few landmark papers elucidating a ligand-binding pathway. Furthermore, we investigated the unstructured Kinase Inducible Domain (KID), a 28-peptide central to signalling and transcriptional response; the kinetics of this challenging system was modelled with a Markovian approach in collaboration with Frank Noe’s group at the Freie University of Berlin. The impact of the funding includes three peer-reviewed publication on high-impact journals; three more papers under review; four MD analysis components, released as open-source software; MD protocols; didactic material, and code for the hosting group.

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The transpressional boundary between the Australian and Pacific plates in the central South Island of New Zealand comprises the Alpine Fault and a broad region of distributed strain concentrated in the Southern Alps but encompassing regions further to the east, including the northwest Canterbury Plains. Low to moderate levels of seismicity (e. g., 2 > M 5 events since 1974 and 2 > M 4.0 in 2009) and Holocene sediments offset or disrupted along rare exposed active fault segments are evidence for ongoing tectonism in the northwest plains, the surface topography of which is remarkably flat and even. Because the geology underlying the late Quaternary alluvial fan deposits that carpet most of the plains is not established, the detailed tectonic evolution of this region and the potential for larger earthquakes is only poorly understood. To address these issues, we have processed and interpreted high-resolution (2.5 m subsurface sampling interval) seismic data acquired along lines strategically located relative to extensive rock exposures to the north, west, and southwest and rare exposures to the east. Geological information provided by these rock exposures offer important constraints on the interpretation of the seismic data. The processed seismic reflection sections image a variably thick layer of generally undisturbed younger (i.e., < 24 ka) Quaternary alluvial sediments unconformably overlying an older (> 59 ka) Quaternary sedimentary sequence that shows evidence of moderate faulting and folding during and subsequent to deposition. These Quaternary units are in unconformable contact with Late Cretaceous-Tertiary interbedded sedimentary and volcanic rocks that are highly faulted, folded, and tilted. The lowest imaged unit is largely reflection-free Permian Triassic basement rocks. Quaternary-age deformation has affected all the rocks underlying the younger alluvial sediments, and there is evidence for ongoing deformation. Eight primary and numerous secondary faults as well as a major anticlinal fold are revealed on the seismic sections. Folded sedimentary and volcanic units are observed in the hanging walls and footwalls of most faults. Five of the primary faults represent plausible extensions of mapped faults, three of which are active. The major anticlinal fold is the probable continuation of known active structure. A magnitude 7.1 earthquake occurred on 4 September 2010 near the southeastern edge of our study area. This predominantly right-lateral strike-slip event and numerous aftershocks (ten with magnitudes >= 5 within one week of the main event) highlight the primary message of our paper: that the generally flat and topographically featureless Canterbury Plains is underlain by a network of active faults that have the potential to generate significant earthquakes.

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This final year project presents the design principles and prototype implementation of BIMS (Biomedical Information Management System), a flexible software system which provides an infrastructure to manage all information required by biomedical research projects.The BIMS project was initiated with the motivation to solve several limitations in medical data acquisition of some research projects, in which Universitat Pompeu Fabra takes part. These limitations,based on the lack of control mechanisms to constraint information submitted by clinicians, impact on the data quality, decreasing it.BIMS can easily be adapted to manage information of a wide variety of clinical studies, not being limited to a given clinical specialty. The software can manage both, textual information, like clinical data (measurements, demographics, diagnostics, etc ...), as well as several kinds of medical images (magnetic resonance imaging, computed tomography, etc ...). Moreover, BIMS provides a web - based graphical user interface and is designed to be deployed in a distributed andmultiuser environment. It is built on top of open source software products and frameworks.Specifically, BIMS has been used to represent all clinical data being currently used within the CardioLab platform (an ongoing project managed by Universitat Pompeu Fabra), demonstratingthat it is a solid software system, which could fulfill requirements of a real production environment.

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We study wave-induced fluid flow effects in porous rocks partially saturated with gas and water, where the saturation patterns are governed by mesoscopic heterogeneities associated with the dry frame properties. The link between the dry frame properties and the gas saturation is defined by the assumption of capillary pressure equilibrium, which in the presence of heterogeneity implies that neighboring regions can exhibit different levels of saturation. In order to determine the equivalent attenuation and phase velocity of the synthetic rock samples considered in this study, we apply a numerical upscaling procedure, which permits to take into account mesoscopic heterogeneities associated with the dry frame properties as well as spatially continuous variations of the pore fluid properties. We consider numerical experiments to analyze such effects in heterogeneous partially saturated porous media, where the saturation field is determined by realistic variations in porosity. Our results indicate that the spatially continuous nature of gas saturation inherent to this study is a critical parameter controlling the seismic response of these environments, which in turn suggests that the physical mechanisms governing partial saturation should be accounted for when analyzing seismic data in a poro-elastic context.

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Developing countries face serious problems on building and using digital libraries (DL) due to low computer and Internet penetration rates, lack of financial resources, etc. Thus, since mobile phones are much more used than computers in these countries, they might be a good alternative for accessing DL. Moreover, in the developed world there has been an exponential growth on the usage of mobile phones for data traffic, establishing a good ground for accessing DL on mobile devices. This paper presents a design proposal for making DSpace-based digital libraries accessible on mobile phones. Since DSpace is a popular free and open source DL system used around the world, making it accessible through mobile devices might contribute for improving the global accessibility of scientific and academic publications.

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Accurate detection of subpopulation size determinations in bimodal populations remains problematic yet it represents a powerful way by which cellular heterogeneity under different environmental conditions can be compared. So far, most studies have relied on qualitative descriptions of population distribution patterns, on population-independent descriptors, or on arbitrary placement of thresholds distinguishing biological ON from OFF states. We found that all these methods fall short of accurately describing small population sizes in bimodal populations. Here we propose a simple, statistics-based method for the analysis of small subpopulation sizes for use in the free software environment R and test this method on real as well as simulated data. Four so-called population splitting methods were designed with different algorithms that can estimate subpopulation sizes from bimodal populations. All four methods proved more precise than previously used methods when analyzing subpopulation sizes of transfer competent cells arising in populations of the bacterium Pseudomonas knackmussii B13. The methods' resolving powers were further explored by bootstrapping and simulations. Two of the methods were not severely limited by the proportions of subpopulations they could estimate correctly, but the two others only allowed accurate subpopulation quantification when this amounted to less than 25% of the total population. In contrast, only one method was still sufficiently accurate with subpopulations smaller than 1% of the total population. This study proposes a number of rational approximations to quantifying small subpopulations and offers an easy-to-use protocol for their implementation in the open source statistical software environment R.

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[ANGLÈS] This project introduces GNSS-SDR, an open source Global Navigation Satellite System software-defined receiver. The lack of reconfigurability of current commercial-of-the-shelf receivers and the advent of new radionavigation signals and systems make software receivers an appealing approach to design new architectures and signal processing algorithms. With the aim of exploring the full potential of this forthcoming scenario with a plurality of new signal structures and frequency bands available for positioning, this paper describes the software architecture design and provides details about its implementation, targeting a multiband, multisystem GNSS receiver. The result is a testbed for GNSS signal processing that allows any kind of customization, including interchangeability of signal sources, signal processing algorithms, interoperability with other systems, output formats, and the offering of interfaces to all the intermediate signals, parameters and variables. The source code release under the GNU General Public License (GPL) secures practical usability, inspection, and continuous improvement by the research community, allowing the discussion based on tangible code and the analysis of results obtained with real signals. The source code is complemented by a development ecosystem, consisting of a website (http://gnss-sdr.org), as well as a revision control system, instructions for users and developers, and communication tools. The project shows in detail the design of the initial blocks of the Signal Processing Plane of the receiver: signal conditioner, the acquisition block and the receiver channel, the project also extends the functionality of the acquisition and tracking modules of the GNSS-SDR receiver to track the new Galileo E1 signals available. Each section provides a theoretical analysis, implementation details of each block and subsequent testing to confirm the calculations with both synthetically generated signals and with real signals from satellites in space.

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Two granitic plutons, the Tso Morari gneiss and the Rupshu metagranite, crop out in the Tso Morari area. The Polokongka La granite, classically interpreted as a young intrusion in the Tso Morari gneiss, has been recognized as the undeformed facies of the latter. Conventional isotope dilution U-Pb zircon dating on single-grain and small multi-grain fractions yielded magmatic ages of 479 +/- 2 Ma for the Tso Morari gneiss and the Polokongka La granite, and 482.5 +/- 1 Ma for the Rupshu granite. There is a great difference in zircon morphology between the Tso Morari gneiss (peraluminous type) and the Rupshu granite (alkaline type). This difference is confirmed by whole-rock chemistry. The Tso Morari gneiss is a typical deformed S-type granite, resulting from crustal anatexis. On the other hand, the Rupshu granite is an essentially metaluminous alkali-calcic intrusion derived from a different source material. Data compilation from other Himalayan Cambro-Ordovician granites reveals huge and widespread magmatic activity all along and beyond the northern Indian plate between 570 and 450 Ma, with a peak at 500-480 Ma. A major, continental-scale tectonic event is required to generate such a large magmatic belt; it has been tentatively compared to the Variscan post-orogenic extensional regime of Western Europe, as a late evolution stage of a Pan-African orogenic event.