2,920 research outputs found

    Some thoughts about nonequilibrium temperature

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    The main objective of this paper is to show that, within the present framework of the kinetic theoretical approach to irreversible thermodynamics, there is no evidence that provides a basis to modify the ordinary Fourier equation relating the heat flux in a non-equilibrium steady state to the gradient of the local equilibrium temperature. This fact is supported, among other arguments, through the kinetic foundations of generalized hydrodynamics. Some attempts have been recently proposed asserting that, in the presence of non-linearities of the state variables, such a temperature should be replaced by the non-equilibrium temperature as defined in Extended Irreversible Thermodynamics. In the approximations used for such a temperature there is so far no evidence that sustains this proposal.Comment: 13 pages, TeX, no figures, to appear in Mol. Phy

    Independent Component Analysis to Detect Clustered Microcalcification Breast Cancers

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    The presence of clustered microcalcifications is one of the earliest signs in breast cancer detection. Although there exist many studies broaching this problem, most of them are nonreproducible due to the use of proprietary image datasets. We use a known subset of the currently largest publicly available mammography database, the Digital Database for Screening Mammography (DDSM), to develop a computer-aided detection system that outperforms the current reproducible studies on the same mammogram set. This proposal is mainly based on the use of extracted image features obtained by independent component analysis, but we also study the inclusion of the patient's age as a nonimage feature which requires no human expertise. Our system achieves an average of 2.55 false positives per image at a sensitivity of 81.8% and 4.45 at a sensitivity of 91.8% in diagnosing the BCRP_CALC_1 subset of DDSM

    Estudio de diferentes protocolos de restricciĂłn alimentaria sobre el desarrollo fetoplacentario en la coneja

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    Two feed strategies (ad libitum throughout pregnancy and restriction during the first 20 days), combined with oestrus synchronization with eCG or not in nulliparous rabbit does, were studied

    Smart toys designed for detecting developmental delays

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    In this paper,we describe the design considerations and implementation of a smart toy system,a technology for supporting the automatic recording and analysis for detecting developmental delays recognition when children play using the smart toy. To achieve this goal,we take advantage of the current commercial sensor features (reliability,low consumption,easy integration,etc.) to develop a series of sensor-based low-cost devices. Specifically,our prototype system consists of a tower of cubes augmented with wireless sensing capabilities and a mobile computing platform that collect the information sent from the cubes allowing the later analysis by childhood development professionals in order to verify a normal behaviour or to detect a potential disorder. This paper presents the requirements of the toy and discusses our choices in toy design,technology used,selected sensors,process to gather data from the sensors and generate information that will help in the decision-making and communication of the information to the collector system. In addition,we also describe the play activities the system supportsAuthors would like to thank the National Programme for Research, Development and Innovation, oriented to Societal Challenges, of the Spanish Ministry for Economy and Competitiveness that supported the results of this paper through EDUCERE project (TIN2013-47803-C2-2-R), and to Universidad de Alcala that supported them through EDUSENS project (CCG2014/EXP-008

    Static quantities of the W boson in the SU_L(3) X U_X(1) model with right-handed neutrinos

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    The static electromagnetic properties of the WW boson, ΔÎș\Delta \kappa and ΔQ\Delta Q, are calculated in the SU_L(3)} \times U_X(1) model with right-handed neutrinos. The new contributions from this model arise from the gauge and scalar sectors. In the gauge sector there is a new contribution from a complex neutral gauge boson Y0Y^0 and a singly-charged gauge boson Y±Y^\pm. The mass of these gauge bosons, called bileptons, is expected to be in the range of a few hundreds of GeV according to the current bounds from experimental data. If the bilepton masses are of the order of 200 GeV, the size of their contribution is similar to that obtained in other weakly coupled theories. However the contributions to both ΔQ\Delta Q and ΔÎș\Delta \kappa are negligible for very heavy or degenerate bileptons. As for the scalar sector, an scenario is examined in which the contribution to the WW form factors is identical to that of a two-Higgs-doublet model. It is found that this sector would not give large corrections to ΔÎș\Delta \kappa and ΔQ\Delta Q.Comment: New material included. Final version to apppear in Physical Review

    Dynamic positioning of floating caissons based on the UKF filter under external perturbances induced by waves

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    This paper presents a dynamic positioning control scheme for concrete caissons in an attempt to automate part of the manoeuvres which usually require a complex deploy of personnel and equipment for port infrastructures development. The aim of this paper is to propose a control scheme, which is able to provide a reduction in costs and an improvement in security for the dynamic positioning manoeuvres . To do so, a dual loop controller is developed and the unscented Kalman filter is applied for states and perturbances estimation. Furthermore, a control allocation algorithm is proposed based on anchoring lines and winches. Finally, some simulations are performed to verify the effectiveness of the proposed approach.The Spanish FEDER/Ministry of Science, Innovation and Universities — State Research Agency (Fig. 14) is greatly acknowledged for funding our research through SAFE Project (Desarrollo de un Sistema Autónomo para el Fondeo de Estructuras para Obras Marítimas), Grant Agreement: RTC-2017-6603-4. The authors would like to thank FCC CO as a collaborator in the development of the SAFE Project. R. Guanche also acknowledges financial support from the Ramon y Cajal Program (RYC-2017-23260) of the Spanish Ministry of Science, Innovation and Universities
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