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Motor speed estimation and failure detection of a small UAV using density of maxima

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Frontiers of Information Technology & Electronic Engineering 2021年第7期22卷 1002-1009页

作者： Jefferson s.sOUZA Moises C.BEZERRIL Mateus A.sILVA Frank C.VERAs Abel LIMA-FILHO Jorge Gabriel ramos Alisson V.BRITO Laboratory of system Engineering and Robotics Federal University of ParaibaJoao PessoaBrazil Department of Information systems Federal University of PiauiPicosBrazil Department of Mechanical Engineering Federal University of ParaibaJoao PessoaBrazil Department of Physics Federal University of ParaibaJoao PessoaBrazil

This work presents the application of the technique named signal analysis based on chaos using density of maxima to analyze brushless direct current *** uses a correlation coefficient estimated from the density of maxima of the current *** study demonstrates in experiments the speed estimation of a brushless motor on a testbench and failure detection in a small flying *** experimental results demonstrate that it is possible to estimate the speed in 97.8%of the cases and to detect failure in 82.75%of the analyzed cases.

关键词： Unmanned aerial vehicle(UAV) speed identification Failure detection Chaos

Emerging patterns in the construction of sejima’s,sanaa’s and Nishizawa’s domestic spaces,from 1987 to 2010

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Frontiers of Architectural Research 2022年第3期11卷 375-401页

作者： Pedro Garcia Martinez Francisco Javier Maroto ramos Universidad Politecnica de Cartagena Escuela Tecnica Superior de Arquitectura y Tecnologfa de EdificationCartagena30201Spain Universidad Politecnica de Madrid Escuela Tecnica Superior de Arquitectura de MadridMadrid28040Spain

sejima and Nishizawa have developed their work without explicitly referencing a theoretical ***,they have stated that their housing projects describe their"architectural biography."This study presents the hypothesis that systermic theories had infu-enced their housing projects at a spatial and constructive *** the aim of testing it,the research produces four lines of ***,we observe that the word system is prominently current in a signifcant sample of their published *** describe how architects like tomi-naga,Ito,Taki,and shinohara,who infuenced sejima when she was still a student,discussed this concept inspired by Christopher Alexander's *** second line brings together all the couple's single-family housing projects published between 1987 and 2010 for the first time in a single document,as well as an original graphic-constructive reconstruction of the most outstanding ***,we unveil the emergence of four constructive patterns by applying these theories to the graphic material ***,we summarize the results in dia-grams,showing the frequency,intensity,and continuity of the identified patterns in the four phases throughout the studied *** the hypothesis facilitates further research relate their domestic work and their other types of projects.

关键词： Architecture House Pattern sejima Nishizawa sANAA

Receiver tube heat transfer analysis of a CCP collector designed based on branched fractals geometry

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International Journal of Agricultural and Biological Engineering 2020年第5期13卷 56-62页

作者： Angélica Palacios Darío Amaya Olga ramos GAV Research Group Universidad Militar Nueva GranadaBogota 110111Colombia

For the development of systems related to renewable energy and specifically for thermo-solar energy,it is essential to study and analyze the different thermal phenomena of heat transfer,in search of the best conditions that allow strengthening the *** such as radiation,convection,and conduction are highly studied,from the field of materials to the field of infrastructure,finding day to day optimal solutions that guarantee a great use of the solar resource available on the earth's *** study presented the results of heat transfer analysis on a receiver pipe in a CCP;designed using the theory of branched fractal geometry to improve the heat transfer associated with concentrating solar capture systems.A fractal structure as a branch or arboreal fractal type network,influenced thermal and electrical parameters,as electrical resistance,thermal resistance,and convective heat transfer,so increasing the level branch heat transfer can be enhancement along of the *** use of renewable energies in agriculture benefits the industrial processes that require a continuous power system,due to climatic conditions and geographical location is not a guarantee in food production fields,which reason solar capture systems contribute to food dehydration processes,water heating,refrigeration,and energy production.

关键词： heat transfer fractal geometry solar collector fractality fractal dimension parabolic cylindrical concentrator

Biocompatibility and electrochemical evaluation of ZrO_(2) thin films deposited by reactive magnetron sputtering on MgZnCa alloy

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Journal of Magnesium and Alloys 2021年第6期9卷 2019-2038页

作者： Benjamín Millán-ramos Daniela Morquecho-Marín Phaedra silva-Bermudez David Ramírez-Ortega Osmary Depablos-Rivera Julieta García-López Mariana Fernández-Lizárraga joséVictoria-Hernández Dietmar Letzig Argelia Almaguer-Flores sandra E.Rodil Instituto de Investigaciones en Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Posgrado en Ciencia e Ingeniería de Materiales Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Unidad de Ingeniería de Tejidos Terapia Celular y Medicina RegenerativaInstituto Nacional de Rehabilitación Luis Guillermo IbarraCDMX 14389Mexico Posgrado en Ciencias Médicas Odontológicas y de la SaludUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico Instituto de Ciencias Aplicadas y Tecnologia Universidad Nacional Autónoma de MéxicoCDMX 04510Mexico Posgrado de Doctorado en Ciencias en Biomedicina y Biotecnología Molecular Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCDMX 11340Mexico Institute of Material and Process Design Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany Magnesium Innovation Centre MagIC Helmholtz-Zentrum GeesthachtMax-Planck-Strasse 1Geesthacht 21502Germany Laboratorio de Biointerfases Facultad de OdontologíaDivisión de Estudios de Posgrado e InvestigaciónUniversidad Nacional Autónoma de MéxicoCDMX 04510Mexico

Biodegradable magnesium alloys are promising candidates for temporary fracture fixation devices in orthopedics;nevertheless,its fast degradation rate at the initial stage after implantation remains as one of the main challenges to be ***_(2)-based coatings to reduce the degradation rate of the Mg-implants are an attractive solution since they show high biocompatibility and *** this work,the degradation,cytotoxicity,and antibacterial performance of ZrO_(2)thin films deposited by magnetron sputtering on a Mg-Zn-Ca alloy was ***-term degradation of ZrO_(2)-coated and uncoated samples was assessed considering electrochemical techniques and H_(2)evolution(gas chromatography).Additionally,long term degradation was assessed by mass-loss *** results showed that a 380 nm ZrO_(2)coating reduces the degradation rate and H_(2)evolution of the alloy during the initial 3 days after immersion but allows the degradation of the bare alloy for the *** ZrO_(2)coating does not compromise the biocompatibility of the alloy and permits better cell adhesion and proliferation of mesenchymal stem cells directly on its surface,in comparison to the bare ***,the ZrO_(2)coating prevents the adhesion and biofilm formation of ***.

关键词： Zirconium dioxide Magnetron sputtering short-term degradation H_(2)evolution

Influence of train speed and its mitigation measures in the short-and long-term performance of a ballastless transition zone

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铁道工程科学:英文版 2023年第4期31卷 309-324页

作者： Ana ramos Rui Calçada António Gomes Correia Department of Civil Engineering Faculty of EngineeringUniversity of PortoCONSTRUCT-LESEPortoPortugal Department of Civil Engineering University of MinhoISISEGuimarãesPortugal

The ballastless track is nowadays the most popular railway system due to the required low number of maintenance opera-tions and costs,despite the high *** gradual change from ballasted to ballastless tracks has been occurring in Asia,but also in Europe,increasing the number of transition *** transition zones are a special area of the railway networks where there is an accelerated process of track degradation,which is a major concern of the railway infrastructure ***,the accurate prediction of the short-and long-term performance of ballastless tracks in transition zones is an important topic in the current paradigm of building/rehabilitating high-speed *** work purposes the development of an advanced 3D model to study the global performance of a ballastless track in an embankment-tunnel transition zone considering the influence of the train speed(220,360,500,and 600 km/h).Moreover,a mitigation measure is also adopted to reduce the stress and displacements levels of the track in the transition.A resilient mat placed in the tunnel and embank-ment aims to soften the *** behaviour of the track with the resilient mat is evaluated considering the influence of the train speed,with special attention regarding the critical *** used methodology is a novel and hybrid approach that allows including short-term and long-term performance,through the development of a powerful 3D model combined with the implementation of a calibrated empirical permanent deformation model.

关键词： Ballastless track Train speed Numerical modelling Transition zone Critical speed

Textural and geochemical characteristics of late Pleistocene to Holocene fine-grained deep-sea sediment cores(GM6 and GM7),recovered from southwestern Gulf of Mexico

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Journal of Palaeogeography 2018年第3期7卷 253-271页

作者： Abigail Anaya-Gregorio John s.Armstrong-Altrin Marfa Luisa Machain-Castillo Patricia C.Montiel-Garcia Mayla A.ramos-Vazquez Licenciatura en Ingenieria en Geologia Ambiental Area Academica de Ciencias de la Tierra y MaterialesUniversidad Autonoma del Estado de HidalgoMineral de la ReformaHidalgoMexico. Instituto de Ciencias del Mary Limnologia Universidad Nacional Autenoma de MexicoUnidad de Procesos Oceanicos y CosterosCiudad Universitaria04510 Ciudad de MexicoMexico. Area Academica de Ciencias de la Tierra y Materiales Universidad Autonoma del Estado de HidalgoCiudad UniversitariaCarretera Pachuca-Tulancingo Km 4.5Col.CarbonerasC.P.42184 Mineral de la ReformaHidalgoMexico. Posgrado en Ciencias del Mary Limnologia Universidad Nacional Autonoma de MexicoCiudad Universitaria3000CoyoacanC.P.04510 Ciudad de MexicoMexico.

Texture, mineralogy, geochemistry, and 14C ages of two deep-sea sediment cores （GM6 and GM7） recovered in the southwestern Gulf of Mexico were investigated to infer their provenance and depositional condition. The sediments are enriched in fine-grained silt and clay and poor in sand content. Mineralogically, the sediments consist of quartz, calcite, smectite, and kaolinite. Based on the ]4C data, the age of the GM6 and GM7 sediment cores were calculated as 23,615 cal yrs. BP and 19,007 cal yrs. BP, respectively. The weathering indices such as chemical index of alteration （CIA）, chemical index of weathering （CIW）, and plagioclase index of alteration （PIA） in GM6 （56-69, 60-74, and 6]-73, respectively） and GM7 （54-69, 57-76, and 55-74, respectively） cores revealed a moderate-to-high intensity of weathering. The rare earth element （REE） patterns suggested that the sediments were derived mostly by the weathering of intermediate rocks, exposed along the coastal regions of the Gulf of Mexico. The trace elemental ratios like V/Cr （〈2）, Ni/Co （〈2）, and Cu/Zn （〈1）, authigenic uranium content （〈1）, and Ce anomaly （Ce/Ce＊ ≤1） suggested that the sediments were deposited under an oxic condition, which was also revealed by the benthic foraminiferal assemblages throughout the GM6 and GM7 sediment cores.

关键词： Radiocarbon age Manganosite Weathering Palaeoredox condition Provenance Holocene Gulf of Mexico

Dynamics in the emergence of dormant and non-dormant herbaceous species from the soil seed bank from a Brazilian dry forest

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Journal of Plant Ecology 2020年第3期13卷 256-265页

作者： josé Djalma de souza Bruno Ayron de souza Aguiar Danielle Melo dos santos Vanessa Kelly Rodrigues de Araujo Júlia Arruda simões Juliana ramos de Andrade Elcida de Lima Araújo Departamento de Biologia Universidade Federal Rural de PernambucoRecifePernambucoBrazil2Universidade Federal de Pernambuco-Centro Acadêmico de VitóriaPernambucoBrazil

Aims In dry tropical forests,herbaceous species may have dormancy mechanisms and form persistent and transient seed banks in the *** acquired,these mechanisms are efficient for the establishment and survival of these herbs,especially in forests with unpredictable climates,such as the ***,our objective was to verify whether the studied herbaceous species adopt the physical dormancy mechanism and how these natural barriers are overcome,to understand the temporal dynamics existing in the soil seed bank from a Brazilian dry tropical *** seeds of five native herbaceous species from the Caatinga forests were selected and submitted to pre-germinative treatments for verifying the presence of physical *** collected soil samples in the rainy and dry seasons for four consecutive years and monitored the emergence of the selected herbaceous in the *** verified the differences in germination and seed bank emergence in the soil by generalized linear *** Findings The presence and absence of physical dormancy were observed in seeds from Caatinga herbaceous *** found intraspecific and interspecific differences in the herbaceous emergence from soil seed banks between years and climatic *** perennial herbs,consecutive lack of emergence between seasons and years was frequent,which suggests a direct relationship with the mechanism of physical dormancy and the environmental conditions necessary to overcome integument *** these species,seed dimorphism and dormancy may confer additional advantages to their ***,presenting intermediate levels of physical dormancy in an annual species may be an evolutionary adjustment to rainfall *** contrast,we found that the annual herb without dormancy is more sensitive to seasonal and interannual climate changes,as evidenced by the increase and significant reduction of its emergence in the soil seed *** differences acquired evoluti

关键词： establishment herbaceous species physical dormancy seed bank seed germination semiarid

Adiponectin as a protective factor in hepatic steatosis

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World Journal of Gastroenterology 2005年第12期11卷 1737-1741页

作者： Nahum Méndez-sánchez Norberto C.Chávez-Tapia Antonio R.Villa Karla sánchez-Lara Daniel Zamora-Valdés Martha H.ramos Misael Uribe Liver Research Unit Clinical Epidemiology Unit

AIM: Obesity and insulin resistance (IR) are closely related to hepatic steatosis (Hs), and adiponectin is a hepatic insulin sensitizer that has important effects in liver function. This study aims at investigating the relationship between serum adiponectin concentration and the presence of Hs. METHODs: We carried out a cross-sectional study in a check-up unit of a University Hospital in Mexico City. We enrolled 196 subjects, comprising 98 subjects with Hs (27 women, 71 men) and 98 controls (37 women and 61 men). Anthropometric, metabolic and biochemical variables were measured in the two groups. serum adiponectin and leptin concentrations were determined, their association with grade of Hs tested, and concentrations, according to quartiles, compared between cases and controls. X2 analysis for linear trends was used to test for a dose-response relationship and logistic regression analysis was conducted to test for a protective effect of adiponectin. REsULTs: The Hs subjects were older and more obese than controls, with a central obesity pattern. In the fourth quartile of adiponectin concentrations, Hs was less common and severe. In a multivariate model of the fourth quartile of the adiponectin concentrations, we observed a protective effect (OR = 0.17, 95%CI: 0.04-0.67, P= 0.01). In subjects with more severe Hs, we observed higher leptin concentrations, and caloric intakes, total fat and iron consumption were higher than in controls. CONCLUsION: The results of the present study suggest that a high serum concentration of adiponectin is associated with a protective effect against Hs.

关键词： Adiponectin Hepatic steatosis Leptin Diet

Two-neutron transfer reactions as a tool to study the interplay between shape coexistence and quantum phase transitions

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Chinese Physics C 2020年第12期44卷 103-113页

作者： J.E.García-ramos J.M.Arias A.Vitturi Departamento de Ciencias Integradas y Centro de Estudios Avanzados en Física Matemática y ComputaciónUniversidad de Huelva21071 HuelvaSpain Instituto Carlos I de Física Teórica y Computacional Universidad de GranadaFuentenueva s/n18071 GranadaSpain Departamento de Física Atómica Molecular y NuclearUniversidad de SevillaApdo.106541080 SevillaSpain Dipartimento di Fisica e Astronomia“Galileo Galilei” Universitádegli Studi di PadovaPadovaItaly

The atomic mass table presents zones where the structure of the states changes rapidly as a function of the neutron or proton *** them,notable examples are the A≈100 Zr region,the Pb region around the neutron midshell(N=104),and the N≈90 rare-earth *** observed phenomena can be understood in terms of either shape coexistence or quantum phase *** objective of this study is to find an observable that can distinguish between both shape coexistence and quantum phase *** an observable to be analyzed,we selected the two-neutron transfer intensity between the 0+states in the parent and daughter *** framework used for this study is the Interacting Boson Model(IBM),including its version with configuration mixing(IBM-CM).To generate wave functions of isotope chains of interest needed for calculating transfer intensities,previous systematic studies using IBM and IBM-CM were used without changing the *** results of two-neutron transfer intensities are presented for Zr,Hg,and Pt isotopic chains using ***,for Zr,Pt,and sm isotopic chains,the results are presented using IBM with only a single configuration,i.e.,without using configuration *** Zr,the two-neutron transfer intensities between the ground states provide a clear observable,indicating that normal and intruder configurations coexist in the low-lying spectrum and cross at A=98→*** can help clarify whether shape coexistence induces a given quantum phase *** Pt,in which shape coexistence is present and the regular and intruder configurations cross for the ground state,there is almost no impact on the value of the two-neutron transfer *** is the situation with Hg,where the ground state always has a regular *** the sm isotope chain,which is one of the quantum phase transition paradigms,the value of the two-neutron transfer intensity is affected strongly.

关键词： two nucleon transfer reactions shape coexistence quantum phase transition interacting boson model