1,519 research outputs found

    A New Tool for Intelligent Parallel Processing of Radar/SAR Remotely Sensed Imagery

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    A novel parallel tool for large-scale image enhancement/reconstruction and postprocessing of radar/SAR sensor systems is addressed. The proposed parallel tool performs the following intelligent processing steps: image formation, for the application of different system-level effects of image degradation with a particular remote sensing (RS) system and simulation of random noising effects, enhancement/reconstruction by employing nonparametric robust high-resolution techniques, and image postprocessing using the fuzzy anisotropic diffusion technique which incorporates a better edge-preserving noise removal effect and faster diffusion process. This innovative tool allows the processing of high-resolution images provided with different radar/SAR sensor systems as required by RS endusers for environmental monitoring, risk prevention, and resource management. To verify the performance implementation of the proposed parallel framework, the processing steps are developed and specifically tested on graphic processing units (GPU), achieving considerable speedups compared to the serial version of the same techniques implemented in C language

    A Fading Channel Simulator Implementation Based on GPU Computing Techniques

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    Channel simulators are powerful tools that permit performance tests of the individual parts of a wireless communication system. This is relevant when new communication algorithms are tested, because it allows us to determine if they fulfill the communications standard requirements. One of these tests consists of evaluating the system performance when a communication channel is considered. In this sense, it is possible to model the channel as an FIR filter with time-varying random coefficients. If the number of coefficients is increased, then a better approach to real scenarios can be achieved; however, in that case, the computational complexity is increased. In order to address this issue, a design methodology for computing the time-varying coefficients of the fading channel simulators using consumer-designed graphic processing units (GPUs) is proposed. With the use of GPUs and the proposed methodology, it is possible for nonspecialized users in parallel computing to accelerate their simulation developments when compared to conventional software. Implementation results show that the proposed approach allows the easy generation of communication channels while reducing the processing time. Finally, GPU-based implementation takes precedence when compared with the CPU-based implementation, due to the scattered nature of the channel. � 2015 R. Carrasco-Alvarez et al

    Inherently Safer Design and Optimization of Intensified Separation Processes for Furfural Production

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    Currently furfural production has been the subject of increased interest because it is a biobased chemical able to compete with fossil-based chemicals. Furfural is characterized by flammability, explosion, and toxicity properties. Improper handling and process design can lead to catastrophic accidents. Hence it is of most importance to use inherent safety concepts during the design stage. This work is the first to present several new downstream separation processes for furfural purification, which are designed using an optimization approach that simultaneously considers safety criteria in addition to the total annual cost and the eco-indicator 99. The proposed schemes include thermally coupled configuration, thermodynamic equivalent configuration, dividing-wall column, and a heat integrated configuration. These are compared with the traditional separation process of furfural known as the Quaker Oats Process. The results show that because of a large amount of water present in the feed, similar values are obtained for total annual cost and eco-indicator 99 in all cases. Moreover, the topology of the processes has an important role in the safety criteria. The thermodynamic equivalent configuration resulted as the safest alternative with a 40% reduction of the inherent risk with respect to the Quaker Oats Process, and thus it is the safest option to purify furfural

    Características físicas de la carne de corderos Katahdín con Pelibuey alimentados a base de forraje y concentrado

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    Objective: To evaluate the effect of forage and concentrate in diet on physical characteristics of meat of crossed (F1) Katahdin with Pelibuey lambs. Design/methodology/approach: Thirty-six entire male lambs were distributed in a completely randomized design to four treatments: 1) 100% Concentrated food (CF) with 15 % of CP; 2) 70% CF + 30% of Maralfalfa forage (Pennisetum sp); 3) 70% CF + 30% of Mombaza forage (M. maximum); 4) 70% CF + 30% CT-115 forage (P. Purpureum). Results: No effect of diet on carcass traits and physical properties of meat was found (P> 0.05). The average value of pH and temperature ± SD were 5.58 ± 0.12 and 6.38 ± 0.56 o C, respectively. The little loss of water in meat (0.1%), indicates that it retains its physical-chemical characteristics for storage. Limitations on study/implications: Consumer demands of lamb meat are more focused on quality traits than quantity details, so, in order to comply with demands demanded by market, it is necessary to carry out meat quality evaluations, compare between breeds and feeding systems to determine which genotype produces the best meat. Findings/conclusions: Lambs fed diets that include forage have similar physical characteristics of meat to those that received only concentrate food, which indicates that it is possible to produce lamb meat with excellent properties, using diets with good quality forage.Objetivo: Evaluar el efecto del forraje y concentrado en la dieta sobre las características físicas de la carne de corderos cruzados (F1) Katahdín × Pelibuey (KtPb). Diseño/metodología/aproximación: Treinta y seis corderos machos enteros fueron distribuidos mediante un diseño completamente al azar a cuatro tratamientos:1) 100% Alimento concentrado (AC) con 15 % de PC: 2) 70% AC + 30% de pasto Maralfalfa (Pennisetum sp); 3) 70% AC + 30% pasto Mombaza (M. maximum ); 4) 70% AC + 30%   CT-115 (P. Purpureum). Resultados: No se encontró un efecto de la dieta sobre las características de la canal y propiedades físicas de la carne (P>0.05). Los valores promedio para el pH y temperatura ± DE encontrados fueron de 5.58 ± 0.12 y 6.38 ± 0.56 o C, respectivamente. La poca pérdida de agua en la carne (0.1%), indica que esta conservo sus propiedades físico-químicas adecuadas para su almacenamiento Limitaciones del estudio/implicaciones: Las demandas de los consumidores de cortes de cordero se centran más en los rasgos de calidad que en los detalles de cantidad. Para poder cumplir con los estándares que exige el mercado, es necesario realizar evaluaciones de calidad de la carne, comparar entre razas y sistemas de alimentación para conocer cual fenotipo produce la mejor carne. Hallazgos/conclusiones: Los corderos alimentados con dietas que incluyen forraje tienen características físicas de la carne similar a los que recibieron solo concentrado, lo que indica que es posible producir carne de corderos con excelentes propiedades, utilizando dietas con forrajes de buena calidad

    VAMOS: a Pathfinder for the HAWC Gamma-Ray Observatory

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    VAMOS was a prototype detector built in 2011 at an altitude of 4100m a.s.l. in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design, construction techniques and data acquisition system of the HAWC observatory. HAWC is an air-shower array currently under construction at the same site of VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water Cherenkov detectors and two different data acquisition systems. It was in operation between October 2011 and May 2012 with an average live time of 30%. Besides the scientific verification purposes, the eight months of data were used to obtain the results presented in this paper: the detector response to the Forbush decrease of March 2012, and the analysis of possible emission, at energies above 30 GeV, for long gamma-ray bursts GRB111016B and GRB120328B.Comment: Accepted for pubblication in Astroparticle Physics Journal (20 pages, 10 figures). Corresponding authors: A.Marinelli and D.Zaboro

    Recommendations of the Spanish Antibiogram Committee (COESANT) for selecting antimicrobial agents and concentrations for in vitro susceptibility studies using automated systems

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    Automated antimicrobial susceptibility testing devices are widely implemented in clinical microbiology laboratories in Spain, mainly using EUCAST (European Committee on Antimicrobial Susceptibility Testing) breakpoints. In 2007, a group of experts published recommendations for including antimicrobial agents and selecting concentrations in these systems. Under the patronage of the Spanish Antibiogram Committee (Comité Español del Antibiograma, COESANT) and the Study Group on Mechanisms of Action and Resistance to Antimicrobial Agents (GEMARA) from the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), and aligned with the Spanish National Plan against Antimicrobial Resistance (PRAN), a group of experts have updated this document. The main modifications from the previous version comprise the inclusion of new antimicrobial agents, adaptation of the ranges of concentrations to cover the EUCAST breakpoints and epidemiological cut-off values (ECOFFs), and the inference of new resistance mechanisms. This proposal should be considered by different manufacturers and users when designing new panels or cards. In addition, recommendations for selective reporting are also included. With this approach, the implementation of EUCAST breakpoints will be easier, increasing the quality of antimicrobial susceptibility testing data and their microbiological interpretation. It will also benefit epidemiological surveillance studies as well as the clinical use of antimicrobials aligned with antimicrobial stewardship programs

    Ultrahigh-energy neutrino follow-up of Gravitational Wave events GW150914 and GW151226 with the Pierre Auger Observatory

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    On September 14, 2015 the Advanced LIGO detectors observed their first gravitational-wave (GW) transient GW150914. This was followed by a second GW event observed on December 26, 2015. Both events were inferred to have arisen from the merger of black holes in binary systems. Such a system may emit neutrinos if there are magnetic fields and disk debris remaining from the formation of the two black holes. With the surface detector array of the Pierre Auger Observatory we can search for neutrinos with energy above 100 PeV from point-like sources across the sky with equatorial declination from about -65 deg. to +60 deg., and in particular from a fraction of the 90% confidence-level (CL) inferred positions in the sky of GW150914 and GW151226. A targeted search for highly-inclined extensive air showers, produced either by interactions of downward-going neutrinos of all flavors in the atmosphere or by the decays of tau leptons originating from tau-neutrino interactions in the Earth's crust (Earth-skimming neutrinos), yielded no candidates in the Auger data collected within ±500\pm 500 s around or 1 day after the coordinated universal time (UTC) of GW150914 and GW151226, as well as in the same search periods relative to the UTC time of the GW candidate event LVT151012. From the non-observation we constrain the amount of energy radiated in ultrahigh-energy neutrinos from such remarkable events.Comment: Published version. Added journal reference and DOI. Added Report Numbe

    Azimuthal asymmetry in the risetime of the surface detector signals of the Pierre Auger Observatory

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    The azimuthal asymmetry in the risetime of signals in Auger surface detector stations is a source of information on shower development. The azimuthal asymmetry is due to a combination of the longitudinal evolution of the shower and geometrical effects related to the angles of incidence of the particles into the detectors. The magnitude of the effect depends upon the zenith angle and state of development of the shower and thus provides a novel observable, (secθ)max(\sec \theta)_\mathrm{max}, sensitive to the mass composition of cosmic rays above 3×10183 \times 10^{18} eV. By comparing measurements with predictions from shower simulations, we find for both of our adopted models of hadronic physics (QGSJETII-04 and EPOS-LHC) an indication that the mean cosmic-ray mass increases slowly with energy, as has been inferred from other studies. However, the mass estimates are dependent on the shower model and on the range of distance from the shower core selected. Thus the method has uncovered further deficiencies in our understanding of shower modelling that must be resolved before the mass composition can be inferred from (secθ)max(\sec \theta)_\mathrm{max}.Comment: Replaced with published version. Added journal reference and DO
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