48 research outputs found
A new three-steps iterative method for solving nonlinear systems
No full textCapdevila, RR.; Cordero Barbero, A.; Torregrosa Sánchez, JR. (2019). A new three-steps iterative method for solving nonlinear systems. R. Company, J. C. Cortés, L. Jódar and E.López-Navarro. 22-25. https://riunet.upv.es/handle/10251/180675S222
Electrical Steels - Chapter 12
No full textA developed electrical system enables power to be generated at key locations and distributed widely.
To realize such a system requires means of generation, distribution and utilization. Electrical steels
play a key role in an electrical system; alongside copper conductors, they make the whole system
feasible. This chapter reviews the production and recent developments, with special attention to
coating technologies, of the two main groups of electrical steels, i.e. the grain-oriented electrical steels
and the non grain-oriented grain electrical steels.The author acknowledges financial support to Spanish Ministerio de Economia y Competitividad
(MINECO) through in the form of a Coordinate Project (MAT2016-80875-C3-1-R). Authors also
acknowledge financial support to Comunidad de Madrid through DIMMAT-CM_S2013/MIT-2775
project.Peer reviewe
Isonormal surfaces: A new tool for the multidimensional dynamical analysis of iterative methods for solving nonlinear systems
No full text[EN] The dynamical behavior of the rational vectorial operator associated with a multidimensional iterative method on polynomial systems gives us interesting information about the stability of the iterative scheme. The stability of fixed points, dynamic planes, bifurcation diagrams, etc. are known tools that provide us this information. In this manuscript, we introduce a new tool, which we call isonormal surface, to complement the information about the stability of the iterative method provided by the dynamical elements mentioned above. These dynamical instruments are used for analyzing the stability of a parametric family of multidimensional iterative schemes in terms of the value of the parameter. Some numerical tests confirm the obtained dynamical results.Ministerio de Ciencia, Innovacion y Universidades (MCIU/AEI/FEDER, UE), Grant/Award Number: PGC2018-095896-B-C22Capdevila-Brown, RR.; Cordero Barbero, A.; Torregrosa Sánchez, JR. (2022). Isonormal surfaces: A new tool for the multidimensional dynamical analysis of iterative methods for solving nonlinear systems. Mathematical Methods in the Applied Sciences. 45(6):3360-3375. https://doi.org/10.1002/mma.7695S3360337545
A new three-step class of iterative methods for solving nonlinear systems
No full text[EN] In this work, a new class of iterative methods for solving nonlinear equations is presented and also its extension for nonlinear systems of equations. This family is developed by using a scalar and matrix weight function procedure, respectively, getting sixth-order of convergence in both cases. Several numerical examples are given to illustrate the efficiency and performance of the proposed methods.This research has been partially supported by both Generalitat Valenciana and Ministerio de Ciencia, Investigacion y Universidades, under grants PROMETEO/2016/089 and PGC2018-095896-B-C22 (MCIU/AEI/FEDER, UE), respectively.Capdevila-Brown, RR.; Cordero Barbero, A.; Torregrosa Sánchez, JR. (2019). A new three-step class of iterative methods for solving nonlinear systems. Mathematics. 7(12):1-14. https://doi.org/10.3390/math7121221S11471
Electrical Steels
No full textChapter 12
Electrical SteelsA developed electrical system enables power to be generated at key locations and distributed widely. To realize such a system requires means of generation, distribution and utilization. Electrical steels play a key role in an electrical system, alongside copper conductors, they make the whole system feasible. This chapter reviews the production and recent developments, with special attention to coating technologies, of the two main groups of electrical steels, i.e. the grain-oriented electrical steels and the non-grain-oriented grain electrical steels.The author acknowledges financial support to Spanish Ministerio de Economia y Competitividad (MINECO) through in the form of a Coordinate Project (MAT2016-80875-C3-1-R). Authors also acknowledge financial support to Comunidad de Madrid through
DIMMAT-CM_S2013/MIT-2775 project
Convergence and dynamical study of a new sixth order convergence iterative scheme for solving nonlinear systems
No full text[EN] A novel family of iterative schemes to estimate the solutions of nonlinear systems is
presented. It is based on the Ermakov-Kalitkin procedure, which widens the set of converging initial
estimations. This class is designed by means of a weight function technique, obtaining 6th-order
convergence. The qualitative properties of the proposed class are analyzed by means of vectorial real
dynamics. Using these tools, the most stable members of the family are selected, and also the chaotical
elements are avoided. Some test vectorial functions are used in order to illustrate the performance and
efficiency of the designed schemesThis research was partially supported by Grant PGC2018-095896-B-C22 funded by MCIN/AEI/31000.13039/ ERDF A way to making Europe , European Union.Capdevila, RR.; Cordero Barbero, A.; Torregrosa Sánchez, JR. (2023). Convergence and dynamical study of a new sixth order convergence iterative scheme for solving nonlinear systems. AIMS Mathematics. 8(6):12751-12777. https://doi.org/10.3934/math.2023642S12751127778
OzDES reverberation mapping program: Lag recovery reliability for 6-yr C iv analysis
No full textThis is a pre-copyedited, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The version of record Monthly Notices of the Royal Astronomical Society 509.3 (2022): 4008-4023 is available online at: https://academic.oup.com/mnras/article-abstract/509/3/4008/6409154?redirectedFrom=fulltextArtículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, los autores pertenecientes a la UAM y el nombre del grupo de colaboración, si lo hubiereWe present the statistical methods that have been developed to analyse the OzDES reverberation mapping sample. To perform this statistical analysis we have created a suite of customizable simulations that mimic the characteristics of each source in the OzDES sample. These characteristics include: the variability in the photometric and spectroscopic light curves, the measurement uncertainties, and the observational cadence. By simulating the sources in the OzDES sample that contain the C iv emission line, we developed a set of criteria that rank the reliability of a recovered time-lag depending on the agreement between different recovery methods, the magnitude of the uncertainties, and the rate at which false positives were found in the simulations. These criteria were applied to simulated light curves and these results used to estimate the quality of the resulting Radius-Luminosity relation. We grade the results using three quality levels (gold, silver, and bronze). The input slope of the R-L relation was recovered within 1σ for each of the three quality samples, with the gold standard having the lowest dispersion with a recovered a R-L relation slope of 0.454 ± 0.016 with an input slope of 0.47. Future work will apply these methods to the entire OzDES sample of 771 AG
DeepZipper: A novel deep-learning architecture for lensed supernovae identification
No full textArtículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAMLarge-scale astronomical surveys have the potential to capture data on large numbers of strongly gravitationally lensed supernovae (LSNe). To facilitate timely analysis and spectroscopic follow-up before the supernova fades, an LSN needs to be identified soon after it begins. To quickly identify LSNe in optical survey data sets, we designed ZipperNet, a multibranch deep neural network that combines convolutional layers (traditionally used for images) with long short-term memory layers (traditionally used for time series). We tested ZipperNet on the task of classifying objects from four categories - no lens, galaxy-galaxy lens, lensed Type-Ia supernova, lensed core-collapse supernova - within high-fidelity simulations of three cosmic survey data sets: the Dark Energy Survey, Rubin Observatory's Legacy Survey of Space and Time (LSST), and a Dark Energy Spectroscopic Instrument (DESI) imaging survey. Among our results, we find that for the LSST-like data set, ZipperNet classifies LSNe with a receiver operating characteristic area under the curve of 0.97, predicts the spectroscopic type of the lensed supernovae with 79% accuracy, and demonstrates similarly high performance for LSNe 1-2 epochs after first detection. We anticipate that a model like ZipperNet, which simultaneously incorporates spatial and temporal information, can play a significant role in the rapid identification of lensed transient systems in cosmic survey experiments. © 2022. The Author(s). Published by the American Astronomical Societ
OzDES reverberation mapping program: Hβ lags from the 6-yr survey
No full textArtículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, los autores pertenecientes a la UAM y el nombre del grupo de colaboración, si lo hubiereThis is a pre-copyedited, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The version of record Monthly Notices of the Royal Astronomical Society 520.2 (2023): 2009-2023 is available online at: https://academic.oup.com/mnras/article-abstract/520/2/2009/6988199?redirectedFrom=fulltext#no-access-messageReverberation mapping measurements have been used to constrain the relationship between the size of the broad-line region and luminosity of active galactic nuclei (AGN). This R-L relation is used to estimate single-epoch virial black hole masses, and has been proposed to use to standardize AGN to determine cosmological distances. We present reverberation measurements made with Hβ from the 6-yr Australian Dark Energy Survey (OzDES) Reverberation Mapping Program. We successfully recover reverberation lags for eight AGN at 0.12 < z < 0.71, probing higher redshifts than the bulk of Hβ measurements made to date. Our fit to the R-L relation has a slope of α = 0.41 ± 0.03 and an intrinsic scatter of σ = 0.23 ± 0.02 dex. The results from our multi-object spectroscopic survey are consistent with previous measurements made by dedicated source-by-source campaigns, and with the observed dependence on accretion rate. Future surveys, including LSST, TiDES, and SDSS-V, which will be revisiting some of our observed fields, will be able to build on the results of our first-generation multi-object reverberation mapping surveyThe DES participants from Spanish institutions are partially supported by MICINN under grants ESP2017-89838, PGC2018-094773, PGC2018-102021, SEV-2016-0588, SEV-2016-0597, and MDM-2015-0509, some of which include ERDF funds from the European Union. IFAE is partially funded by the CERCA program of the Generalitat de Catalunya. Research leading to these re-sults has received funding from the European Research Council under the European Union’s Seventh Framework Program (FP7/2007-2013) including ERC grant agreements 240672, 291329, and 306478. We acknowledge support from the Brazilian Instituto Nacional de Ciên-cia e Tecnologia (INCT) do e-Universo (CNPq grant 465376/2014-2).
This manuscript has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. De-partment of Energy, Office of Science, Office of High Energy Physics
Frataxin deficiency increases cyclooxygenase 2 and prostaglandins in cell and animal models of Friedreich's ataxia
No full text© The Author 2014. Published by Oxford University Press
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.An inherited deficiency of the mitochondrial protein frataxin causes Friedreich's ataxia (FRDA); the mechanism by which this deficiency triggers neuro- and cardio-degeneration is unclear. Microarrays of neural tissue of animal models of the disease showed decreases in antioxidant genes, and increases in inflammatory genes. Cyclooxygenase (COX)-derived oxylipins are important mediators of inflammation. We measured oxylipin levels using tandem mass spectrometry and ELISAs in multiple cell and animal models of FRDA. Mass spectrometry revealed increases in concentrations of prostaglandins, thromboxane B2, 15-HETE and 11-HETE in cerebellar samples of knockin knockout mice. One possible explanation for the elevated oxylipins is that frataxin deficiency results in increased COX activity. While constitutive COX1 was unchanged, inducible COX2 expression was elevated over 1.35-fold (P < 0.05) in two Friedreich's mouse models and Friedreich's lymphocytes. Consistent with higher COX2 expression, its activity was also increased by 58% over controls. COX2 expression is driven by multiple transcription factors, including activator protein 1 and cAMP response element-binding protein, both of which were elevated over 1.52-fold in cerebella. Taken together, the results support the hypothesis that reduced expression of frataxin leads to elevation of COX2-mediated oxylipin synthesis stimulated by increases in transcription factors that respond to increased reactive oxygen species. These findings support a neuroinflammatory mechanism in FRDA, which has both pathomechanistic and therapeutic implications.The study was supported by NIH grants NS077777, EY012245 and AG025532 to G.A.C., and USDA-ARS Intramural Projects 5306-51530-019-00D and 1 U24 DK097154-01 to J.W.N. Funding to pay the Open Access publication charges for this article was provided by the NIH
