4,527 research outputs found

    Optimizing texture feature extraction in image analysis by using experimental design theory

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    Microscopic study of neutron-rich Dysprosium isotopes

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    Microscopic studies in heavy nuclei are very scarce due to large valence spaces involved. This computational problem can be avoided by means of the use of symmetry based models. Ground-state, gamma and beta-bands, and their B(E2) transition strengths in 160-168Dy isotopes, are studied in the framework of the pseudo-SU(3) model which includes the preserving symmetry Q.Q term and the symmetry-breaking Nilsson and pairing terms, systematically parametrized. Additionally, three rotor-like terms are considered whose free parameters, fixed for all members of the chain are used to fine tune the moment of inertia of rotational bands and the band-head of gamma and beta-bands. The model succesfully describes in a systematic way rotational features in these nuclei and allows to extrapolate toward the midshell nucleus 170Dy. The results presented show that it is possible to study full chain of isotopes or isotones in the region with the present model

    Evolution and ecology of antarctic sponges

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    Sponges are abundant and species-rich in Antarctic waters, and play important roles in the benthic ecosystems of the continent. The taxonomy of Antarctic sponges is, to some extent, well established, yet the phylogenetic relationships of this fauna remain unknown. Here, the first contributions to the knowledge of the evolution of Antarctic sponges are presented. A molecular phylogeny for the common Antarctic shelf glass sponge genus Rossella is provided. Based on nuclear and mitochondrial markers, it is shown that many of the species described for the genus, which usually are morphologically poorly defined and difficult to differentiate, likely, represent a single species (Rossella racovitzae) or a species complex. The deep Southern Ocean has yielded numerous, most likely new, species of the demosponge Familiy Cladorhizidae. Cladohizidae groups sponges largely known by their carnivorous habit, which is usually accompanied by the lack, or strong modification, of the sponge aquiferous system and by a distinct stipitate body shape. Cladorhizids are also important for the broader understanding of the phylogenetic relationships of the Order Poecilosclerida. In this study, the debated phylogenetic position of the genus Abyssocladia is clarified using recent collections of cladorhizid sponges and a (remarkable) new species of the genus Phelloderma (Phellodermidae) from the Southern Ocean, and partial sequences of the (nuclear) 28S rDNA and of the (mitochondrial) COI. The results show that Abyssocladia is a cladorhizid sponge and that Cladorhizidae is monophyletic, the consequences of these results for the prevalent interpretation of the evolution of poecilosclerid sponges are also discussed. The diversity of Antarctic sponges occurring on the shelf has been compared to that of tropical and subtropical ecosystems. Less is known about the sponge communities inhabiting the deeper waters of the Southern Ocean. The lack of information on deep benthic habitats, mainly due to the fact that sampling remote ecosystem such as Antarctica or the deep sea is expensive and technically difficult, hampers the determination of the number of species that inhabit the vast area of the deep Southern Ocean. In this work, estimation methods are used to predict lower bounds for the number of deep sea sponge species occurring in the Weddell Sea, Western Antarctica, and to show that the deep sea can be as rich as the shelf and that the total number of sponge species in Antarctica could be more than previously considered. Finally, a middle throughput DNA barcoding workflow for processing sponges was established and the performance of this analytical pipeline was analyzed based on a large collection (∼8300 specimens) of sponges from Australia avail- able for DNA barcoding. The barcoding workflow was also used to provide a comprehensive DNA-barcode database for the Ross Sea comprising ∼50 species of demosponges and covering ∼80% of the sponge species characteristic for this area. The generated barcode database was used to provide evidence for a long history of in situ evolution in Antarctic sponges, which is congruent with previous biogeographic hypotheses suggesting an ancient origin for Antarctic sponges

    Invernadero automatizado, instrumentación y lógica difusa

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    Crops are vulnerable to climatic conditions; therefore, their quality may vary according to environmental behavior. Under optimal conditions the crop can have a good productive development and an increase in the yield per unit area, reducing the risks caused by climatic changes, pests and diseases. With the electronic application in greenhouses it is possible to make efficient use of the resources since these can be controlled according to each stage of the development of the crop. Being in an isolated environment, in other words, independent of the external environment, it is possible to carry out production at any time of the year, thanks to the microclimates.  The following paper shows the development of an automated greenhouse using electronic instrumentation to control its irrigation, lighting, humidification and ventilation systems using fuzzy logic.Los cultivos son susceptibles a condiciones climáticas, por ende, la calidad de los mismos puede variar según el comportamiento ambiental. Bajo condiciones óptimas el cultivo puede tener un buen desarrollo productivo y un aumento en el rendimiento por unidad de superficie, reduciendo los riesgos causados por cambios climatológicos, plagas y enfermedades. Con la aplicación de electrónica en invernaderos es posible hacer uso eficiente de los recursos ya que se pueden controlar según cada etapa fenológica del cultivo. Al estar en un ambiente aislado, es decir independiente del medio exterior, es posible realizar producción en cualquier época del año, lo anterior gracias a los microclimas. El siguiente articulo muestra el desarrollo de un invernadero automatizado haciendo uso de instrumentación electrónica para controlar mediante lógica difusa sus sistemas de riego, luz, humidificación y ventilación

    Fabric defect detection using the wavelet transform in an ARM processor

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    Small devices used in our day life are constructed with powerful architectures that can be used for industrial applications when requiring portability and communication facilities. We present in this paper an example of the use of an embedded system, the Zeus epic 520 single board computer, for defect detection in textiles using image processing. We implement the Haar wavelet transform using the embedded visual C++ 4.0 compiler for Windows CE 5. The algorithm was tested for defect detection using images of fabrics with five types of defects. An average of 95% in terms of correct defect detection was obtained, achieving a similar performance than using processors with float point arithmetic calculations

    Signalling Three-Way Intersections: Is Redundancy Better Than Only Mandatory or Prohibitory Signs?

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    This work was supported by the Spanish Government, Ministry of Economy and Competitiveness (PGC2018-095868-B-I00).At intersections, drivers need to infer which ways are allowed by interpreting mandatory and/or prohibitory traffic signs. Time and accuracy in this decision-making process are crucial factors to avoid accidents. Previous studies show that integrating information from prohibitory signs is generally more difficult than from mandatory signs. In Study 1, we compare combined redundant signalling conditions to simple sign conditions at three-way intersections. In Study 2, we carried out a survey among professionals responsible for signposting to test whether common practices are consistent with experimental research. In Study 1, an experimental task was applied (n = 24), and in Study 2, the survey response rate was 17%. These included the main cities in Spain such as Madrid and Barcelona. Study 1 showed that inferences with mandatory signs are faster than those with prohibitory signs, and redundant information is an improvement only on prohibitory signs. In Study 2, prohibitory signs were those most frequently chosen by professionals responsible for signposting. In conclusion, the most used signs, according to the laboratory study, were not the best ones for signposting because the faster responses were obtained for mandatory signs, and in second place for redundant signs.Spanish Government, Ministry of Economy and Competitiveness PGC2018-095868-B-I0

    Mathematical Formulation and Numerical Validation of Uncertainty Costs for Controllable Loads

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    Este documento presenta el desarrollo de una nueva formulación matemática para definir, a través de enfoques probabilísticos, el costo que puede generarse si existiera un mercado eléctrico diversificado, con participación activa de la demanda. Para ello, se considera que la demanda eléctrica en un instante de tiempo sigue una distribución determinada de probabilidad y es controlable por el operador del sistema. El estudio muestra un desarrollo matemático del costo de incertidumbre de la demanda a partir del cálculo del costo esperado de suplir el valor de demanda más conveniente para el sistema de potencia. La validación de la fórmula analítica se realiza a través del método de Monte Carlo, que permitió comparar los costos de penalización asociados con la subestimación o sobreestimación de la demanda de energía eléctrica.This document presents an analysis and development of a new mathematical formulation to determine, through probabilistic approaches, the cost that can appear in a diversified electricity market with active load participation. In our approach, we consider that power demand follows a specific probability distribution and its control is performed through system's operator actions. The cost of uncertainty of demand is mathematically developed by calculating the expected cost of supplying the most convenient demand value for the power system. The validation of the analytical formula is done through the Monte Carlo method, that allowed us to compare the penalty costs in the case of underestimating or overestimating the demand for electrical energy.Peer Reviewe

    Short-Term Exposure to High-Temperature Water Causes a Shift in the Microbiome of the Common Aquarium Sponge Lendenfeldia chondrodes

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    Marine sponges harbor diverse microbiomes that contribute to their energetic and metabolic needs. Although numerous studies on sponge microbial diversity exist, relatively few focused on sponge microbial community changes under different sources of environmental stress. In this study, we assess the impact of elevated seawater temperature on the microbiome of cultured Lendenfeldia chondrodes, a coral reef sponge commonly found in marine aquaria. Lendenfeldia chondrodes exhibits high thermal tolerance showing no evidence of tissue damage or bleaching at 5~°C above control water temperature (26~°C). High-throughput sequencing of the bacterial 16S rRNA V4 region revealed a response of the microbiome of L. chondrodes to short-term exposure to elevated seawater temperature. Shifts in abundance and richness of the dominant bacterial phyla found in the microbiome of this species, namely Proteobacteria, Cyanobacteria, Planctomycetes, and Bacteroidetes, characterized this response. The observed resilience of L. chondrodes and the responsiveness of its microbiome to short-term increases in seawater temperature suggest that this holobiont may be capable of acclimating to anthropogenic-driven sublethal environmental stress via a re-accommodation of its associated bacterial community. This sheds a new light on the potential for resilience of some sponges to increasing surface seawater temperatures and associated projected regime shifts in coral reefs

    Fully Planar Dual-Polarized Broadband Antenna for 3G, 4G and Sub 6-GHz 5G Base Stations

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    A fully planar dual polarized radiating element with internal embedded coupled dipoles is presented in this paper. The inclusion of these elements allows achieving three different goals: firstly, an extension of the bandwidth towards lower frequencies (from 1.69 GHz to 1.427 GHz) as required in new 5G standards; secondly, a reduction of the antenna size in comparison with other topologies for bandwidth extension and, finally, a reduction of the secondary lobes. The proposed dual polarized broadband antenna is based on two sets of dual polarized dipoles, with a fully planar structure. The objective of this paper is the design of an antenna working in the extended 5G band in order to fulfil the future 5G requirement in the microwave region, in which the new frequency bandwidth goes from 1.427 up to 2.69 GHz with the return losses lower than -14 dB and the crosspolar isolation larger than 28 dB.This work was supported in part by the Spanish Ministry of Education, Culture and Sport under a grant for predoctoral contracts for University Teacher Training under Grant FPU16/00459, and in part by the Spanish Ministry of Science, Innovation and Universities, (program ``Programa Estatal de I+D+i orientada a los Retos de la Sociedad'') under Grant RTC-2017-6394-7

    The Biology and Evolution of Calcite and Aragonite Mineralization in Octocorallia

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    Octocorallia (class Anthozoa, phylum Cnidaria) is a group of calcifying corals displaying a wide diversity of mineral skeletons. This includes skeletal structures composed of different calcium carbonate polymorphs (aragonite and calcite). This represents a unique feature among anthozoans, as scleractinian corals (subclass Hexacorallia), main reef builders and focus of biomineralization research, are all characterized by an aragonite exoskeleton. From an evolutionary perspective, the presence of aragonitic skeletons in Octocorallia is puzzling as it is observed in very few species and has apparently originated during a Calcite sea (i.e., time interval characterized by calcite-inducing seawater conditions). Despite this, octocorals have been systematically overlooked in biomineralization studies. Here we review what is known about octocoral biomineralization, focusing on the evolutionary and biological processes that underlie calcite and aragonite formation. Although differences in research focus between octocorals and scleractinians are often mentioned, we highlight how strong variability also exists between different octocoral groups. Different main aspects of octocoral biomineralization have been in fact studied in a small set of species, including the (calcitic) gorgonian Leptogorgia virgulata and/or the precious coral Corallium rubrum. These include descriptions of calcifying cells (scleroblasts), calcium transport and chemistry of the calcification fluids. With the exception of few histological observations, no information on these features is available for aragonitic octocorals. Availability of sequencing data is also heterogeneous between groups, with no transcriptome or genome available, for instance, for the clade Calcaxonia. Although calcite represents by far the most common polymorph deposited by octocorals, we argue that studying aragonite-forming could provide insight on octocoral, and more generally anthozoan, biomineralization. First and foremost it would allow to compare calcification processes between octocoral groups, highlighting homologies and differences. Secondly, similarities (exoskeleton) between Heliopora and scleractinian skeletons, would provide further insight on which biomineralization features are driven by skeleton characteristics (shared by scleractinians and aragonitic octocorals) and those driven by taxonomy (shared by octocorals regardless of skeleton polymorph). Including the diversity of anthozoan mineralization strategies into biomineralization studies remains thus essential to comprehensively study how skeletons form and evolved within this ecologically important group of marine animals
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