8,854 research outputs found

    Characterization of second type plane foliations using Newton polygons

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    In this article we characterize the foliations that have the same Newton polygon that their union of formal separatrices, they are the foliations called of the second type. In the case of cuspidal foliations studied by Loray, we precise this characterization using the Poincar\'e-Hopf index. This index also characterizes the cuspidal foliations having the same desingularization that the union of its separatrices. Finally we give necessary and sufficient conditions when these cuspidal foliations are generalized curves, and a characterization when they have only one separatrix.Comment: 15 page

    Modeling and simulation of integration of internet of things and manufacturing industry 4.0

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    Internet of Things (IoT) is changing the processes in the manufacturing industry. It is creating new opportunities for both economies and society. The deployment of Internet of Things for the development of Industry 4.0 improves processes and manufacturing systems. In this type of systems, the information is related to the manufacturing status, trends in energy consumption by machinery, material logistics, customer orders, supply data and all data related to smart devices implemented in the processes. This paper describes an Internet of Things architecture applied to industry, a metamodel of integration in its phase II (Internet of things, social networks, cloud and industry 4.0) for the generation of applications for Industry 4.0.http://unidadinvestigacion.usta.edu.c

    Biophysical Processes Determining the Connectivity of the Alboran Sea Fish Populations

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    This chapter revises biogeophysical issues of connectivity processes for fish populations in the Alboran Sea—Strait of Gibraltar—Gulf of Cadiz area. Connectivity of early life history stages between distant spawning grounds is crucial to incorporate vital developmental rates that condition survival probabilities at critical ontogenic stages. Hydrodynamics is pivotal to the process and most particular for pelagic species originating from adult fish adapted to recurrent patterns. Therefore, special focus has been placed on the hydrodynamics of the region, particularly on the Alboran Sea where the swift and energetic eastward-flowing Atlantic Jet entering the basin from the Strait of Gibraltar determines the surface circulation patterns. The Jet establishes an obvious zonal west-to-east connectivity, prevents the one in the opposite east-to-west direction and works as a hydrodynamic barrier that hampers the north-to-south connectivity. The chapter addresses these processes, discusses possible mechanisms to achieve connectivity between north and south shores, which have to overcome the hydrodynamic barrier, and assesses the feasibility of east-to-west connectivity by means of intermediate-depth currents. Implications on the populations and ecosystems of the Alboran Sea and on the three main harvested species potentially affected by hydrodynamic connectivity in the basin (European hake, the sardine, and the blackspot seabream) are also commented.Preprin

    Soil and leaf mineral element contents in mediterranean vineyards: bioaccumulation and potential soil pollution

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    The study reported here concerns the geochemical distributions of macro- and trace elements (including potentially toxic elements, PTEs) in the vineyard soils of Alcubillas, which is one of the oldest, albeit not world-renowned, wine-growing areas in La Mancha (Central Spain). Soil and leaf samples were analyzed by X-ray fluorescence spectrometry to ascertain the levels of various elements in the soil and the plant. The potential toxicity of the elements was assessed with regard to the development of the vineyard. Despite the fact that fertilizers and pesticides are employed in the vineyards in this area, the results showed that the levels of trace elements in the soil samples did not exceed the reference values according the pedogeochemical values for the region and Spain. This finding suggests that the study area is not polluted, and therefore, there are hardly any traces of anthropogenic contamination. The Biological Absorption Coefficient (BAC) was calculated to assess the assimilation of various elements from the soil to the leaves, and differences were found in the element absorption capacity of the vines. Some elements were not taken up by Vitis vinifera despite elements like Zr and Rb being present in relatively high concentrations in the soil. The production in these soils does not represent a threat to human health or the ecosystem, because the farmers in this area are extremely careful to preserve the environment and they only farm to achieve moderate yields of grapes per hectar

    Mechanical canopy and trunk shaking for the harvesting mechanization of table olive orchards

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    Table olive harvesting is highly dependent on manual labour and may jeopardize the crop benefit. The introduction of a mechanical harvest system requires a global evaluation of the whole process. A trunk shaker along with shaker combs and a continuous canopy shaker harvester have been tested in two orchards with different tree training and layout to determine their feasibility to mechanical harvesting in table olives. For that purpose, several parameters have been evaluated. Canopy shaker required adapted orchard layout and hedge of canopies for reaching an acceptable harvesting efficiency about 80% and trunk shaker performed a higher efficiency of more than 95% but depended highly on labour. Both systems had a high field capacity about 0.15 ha h-1 but low for the trunk shaker considering the people (0.01 ha h-1 person-1). The vibration pattern that applied on branches was totally different although the quantitative tree damages were no significative different. There were no significant differences in fruit bruising between both systems, but there were between the different sampling points, mainly in the detachment. The fruit bruising index of the remaining fruit on canopy suggests that it is possible to perform a second harvest. Both mechanical systems are suitable for table olive harvesting whilst improving the efficiency of manual systems with bearable damages, but each one has pros and cons that must be considered bearing in mind that require an adaptation of the orchard where there are applied. Highlights Table olives mechanization is possible by integrating with the fruit liquid store. Trunk shaker performed high efficiency in adapted orchards but depended on labour. Canopy shakers require the adaption of orchard and machine for commercial purposes. There were no differences in detached fruit bruising between both mechanical systems. The bruising index of the remaining fruit on trees suggest second harvesting pass.Table olive harvesting is highly dependent on manual labour and may jeopardize the crop benefit. The introduction of a mechanical harvest system requires a global evaluation of the whole process. A trunk shaker along with shaker combs and a continuous canopy shaker harvester have been tested in two orchards with different tree training and layout to determine their feasibility to mechanical harvesting in table olives. For that purpose, several parameters have been evaluated. Canopy shaker required adapted orchard layout and hedge of canopies for reaching an acceptable harvesting efficiency about 80% and trunk shaker performed a higher efficiency of more than 95% but depended highly on labour. Both systems had a high field capacity about 0.15 ha h-1 but low for the trunk shaker considering the people (0.01 ha h-1 person-1). The vibration pattern that applied on branches was totally different although the quantitative tree damages were no significative different. There were no significant differences in fruit bruising between both systems, but there were between the different sampling points, mainly in the detachment. The fruit bruising index of the remaining fruit on canopy suggests that it is possible to perform a second harvest. Both mechanical systems are suitable for table olive harvesting whilst improving the efficiency of manual systems with bearable damages, but each one has pros and cons that must be considered bearing in mind that require an adaptation of the orchard where there are applied. Highlights Table olives mechanization is possible by integrating with the fruit liquid store. Trunk shaker performed high efficiency in adapted orchards but depended on labour. Canopy shakers require the adaption of orchard and machine for commercial purposes. There were no differences in detached fruit bruising between both mechanical systems. The bruising index of the remaining fruit on trees suggest second harvesting pass

    Imprints of galaxy evolution on H ii regions Memory of the past uncovered by the CALIFA survey

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    H ii regions in galaxies are the sites of star formation and thus particular places to understand the build-up of stellar mass in the universe. The line ratios of this ionized gas are frequently used to characterize the ionization conditions. We use the Hii regions catalogue from the CALIFA survey (~5000 H ii regions), to explore their distribution across the classical [OIII]/Hbeta vs. [NII]/Halpha diagnostic diagram, and how it depends on the oxygen abundance, ionization parameter, electron density, and dust attenuation. We compared the line ratios with predictions from photoionization models. Finally, we explore the dependences on the properties of the host galaxies, the location within those galaxies and the properties of the underlying stellar population. We found that the location within the BPT diagrams is not totally predicted by photoionization models. Indeed, it depends on the properties of the host galaxies, their galactocentric distances and the properties of the underlying stellar population. These results indicate that although H ii regions are short lived events, they are affected by the total underlying stellar population. One may say that H ii regions keep a memory of the stellar evolution and chemical enrichment that have left an imprint on the both the ionizing stellar population and the ionized gasComment: 18 pages, 8 figures, accepted for publishing in A&

    Easily retrievable objects among the NEO population

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    Asteroids and comets are of strategic importance for science in an effort to understand the formation, evolution and composition of the Solar System. Near-Earth Objects (NEOs) are of particular interest because of their accessibility from Earth, but also because of their speculated wealth of material resources. The exploitation of these resources has long been discussed as a means to lower the cost of future space endeavours. In this paper, we consider the currently known NEO population and define a family of so-called Easily Retrievable Objects (EROs), objects that can be transported from accessible heliocentric orbits into the Earth’s neighbourhood at affordable costs. The asteroid retrieval transfers are sought from the continuum of low energy transfers enabled by the dynamics of invariant manifolds; specifically, the retrieval transfers target planar, vertical Lyapunov and halo orbit families associated with the collinear equilibrium points of the Sun-Earth Circular Restricted Three Body problem. The judicious use of these dynamical features provides the best opportunity to find extremely low energy Earth transfers for asteroid material. A catalogue of asteroid retrieval candidates is then presented. Despite the highly incomplete census of very small asteroids, the ERO catalogue can already be populated with 12 different objects retrievable with less than 500 m/s of Δv. Moreover, the approach proposed represents a robust search and ranking methodology for future retrieval candidates that can be automatically applied to the growing survey of NEOs

    Knowing your place and commanding space:de/constructions of gendered embodiment in mixed-sex karate

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    Feminists have long acknowledged that gendered divisions in access to spaces of leisure, and how women and men physically take up that space, reproduces gender inequality. This article will explore how karate practitioners participate in the space of mixed-sex karate practice and how such uses of space de/construct gendered embodiments and a gender hierarchy. Data presented is drawn from nine months of ethnographic emersion within three karate clubs and fifteen photo-elicitation interviews with karate participants from the three clubs. The findings of this paper suggest that whilst women often occupied spaces of expertise within the karate hall, gendered distinctions in uses of space emerged in the more subtle ways in which women and men used their voice, responded to the tacit and smelt dilemmas of sweat, and moved their bodies across physical space. This research highlights both the potential of physical leisure practice to ‘undo’ conventional gendered embodiments that particularly restrict women’s intentionality in the world (Young, 1980), and the power of spatially-attuned research to illuminate the minute ways in which unequal gender relations are naturalised, legitimised and done

    Post-glacial evolution of alpine environments in the western Mediterranean region : The Laguna Seca record

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    In an effort to understand how alpine environments from the western Mediterranean region responded to climate variations since the last glacial-interglacial transition, a detailed chronological control and sedimentological analysis, supported by magnetic susceptibility, total organic carbon and C/N data, were carried out on the sedimentary record of Laguna Seca (LS). This is a latitudinal and altitudinally (2259 masl) key alpine wetland site located in the easternmost area of the Sierra Nevada, southern Iberian Peninsula, where sediments accumulated during Heinrich Stadial 1, Bolling-Allerod (B-A) and the Younger Dryas (YD) previously unrecorded in alpine Sierra Nevada. Climate controlled sedimentation in LS and three coarse-grained and one fine-grained facies association are differentiated, which help us decipher the paleoenvironmental evolution of LS: (1) subaerial cohesionless debris flows during a paraglacial stage; (2) till or nival diamicton during a small glacier/nivation hollow stage; (3) massive mudstone by suspension settling of clays into standing water during a lacustrine stage; and (4) frost-shattering breccia deposited inside the lacustrine stage, probably during the YD, and linked to a periglacial substage. The development of a previously existing small glacial cirque during the Last Glacial Maximum (LGM) in the LS basin at an elevation between 2500 and 2300 m could be supported by the important availability of slope sediments glacially-conditioned such as debris flows, reworked by paraglacial slope processes during the first deglaciation stages, confirming previous studies of landforms in the catchment area and the LGM-Equilibrium Line Altitude estimation above 2400 masl in Sierra Nevada. Mean sediment accumulation rates in the LS sedimentary units (4.21 and 0.28 mm/yr during the paraglacial small glacier/nivation stage and the lacustrine stage, respectively) confirm that geomorphic activity accelerated just after glaciers retreated due to a slope adjustment and high availability of glacially conditioned sediments. An abrupt change in paleoenvironmental and paleoclimatic conditions occurred in LS at ~ 15.7 cal kyr BP. This change was probably due to an increase in temperature and precipitation in the western Mediterranean region during the B-A. At LS, this resulted in significant ice-melt, forming a deep-water lake in LS with important organic matter contribution until the end of the Early Holocene (except in the YD when the lake level probably dropped), but elsewhere a general glacier recession in the Sierra Nevada and an expansion of the Mediterranean forest in the southern Iberian Peninsula. Finally, the general long-term aridification that occurred during the Middle Holocene until the present in the western Mediterranean region triggered an important environmental change transforming LS into an ephemeral wetland with an increase in aquatic productivity.Peer reviewe
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