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Understanding root-zone soil moisture in agricultural regions of Central Mexico using the ensemble Kalman filter,satellite-derived information,and the THEXMEX-18 dataset

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International Journal of Digital Earth 2022年第1期15卷 52-78页

作者： Héctor Ernesto Huerta-Bátiz Daniel Enrique Constantino-Recillas Alejandro Monsiváis-Huertero Juan Carlos Hernández-Sánchez Jasmeet Judge Ramón Sidonio Aparicio-García escuela superior de Ingeniería mecánica y eléctrica Unidad Ticomán Instituto Politécnico NacionalMexico CityMexico escuela superior de Ingeniería mecánica y eléctrica Unidad Zacatenco Instituto Politécnico NacionalMexico CityMexico Tecnológico Nacional de México-TESE EcatepecMexico department of Agricultural and Biological Engineering University of FloridaGainesvilleFLUSA

An Ensemble Kalman Filter(EnKF)-based assimilation algorithm was implemented to estimate root-zone soil moisture(RZSM)using a Soil-Vegetation-Atmosphere Transfer(SVAT)model during a complete growing season of corn in Central Mexico.Synthetic and field soil moisture(SM)observations and NASA SMAP SM retrievals were used to understand the effect of vertically spatial updates and uncertainties in meteorological forcings on RZSM estimates.Assimilation of RZSM every 3 days using SM observations at 4 depths lowered the averaged standard deviation(ASD)and the root mean square error(RMSE)by 60%and 50%,respectively,compared to the open-loop ASD.The assimilation of synthetic SM at the top 0-5 cm obtained RZSM closer to observations compared to THEXMEX-18 SM measurements and SMAP SM retrievals.Differences between EnKF estimates and SM observations and SMAP SM retrievals are mainly due to misrepresentation of vegetation conditions.The results improved SM estimates up to 10-cm depth using SMAP SM retrievals;however,additional studies are needed to improve SM at deeper layers.The implemented methodology can estimate SM at the top 10 cm of the soil every 3 days to mitigate the impact of the climate change on agricultural production over rainfed areas,particularly in developing countries.

关键词： Root-zone soil moisture SVAT model ensemble kalman filter soil moisture active-Passive(SMAP)mission agricultural region THEXMEX-18 central Mexico

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Spin Number Coherent States and the Problem of Two Coupled Oscillators

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Communications in Theoretical Physics 2015年第7期64卷 34-38页

作者： D.Ojeda-Guillén R.D.Mota V.D.Granados escuela superior de Fisica y Matemáticas Instituto Politécnico Nacional Ed. 9 Unidad Profesional Adolfo López Mateos Escuela Superior de Ingenieria Mecánica y Eléctrica Unidad Culhuacán Instituto Politécnico Nacional

From the definition of the standard Perelomov coherent states we introduce the Perelomov number coherent states for any su(2) Lie algebra. With the displacement operator we apply a similarity transformation to the su(2)generators and construct a new set of operators which also close the su(2) Lie algebra, being the Perelomov number coherent states the new basis for its unitary irreducible representation. We apply our results to obtain the energy spectrum, the eigenstates and the partition function of two coupled oscillators. We show that the eigenstates of two coupled oscillators are the SU(2) Perelomov number coherent states of the two-dimensional harmonic oscillator with an appropriate choice of the coherent state parameters.

关键词： coherent states Lie algebras coupled oscillators

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Preparation of Rod-like Aluminum Doped Zinc Oxide Powders by Sol-gel Technique Using Metal Chlorides and Acetylacetone Precursors

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Journal of Wuhan University of Technology(Materials Science) 2018年第6期33卷 1293-1297页

作者： KESHTKAR Javad VARGAS GARCIA Jorge Roberto GALAVIZ PEREZ Jorge MARTINEZ TRINIDAD José Escuela Superior de Ingenieria Mecánica y Eléctrica Instituto Politécnico NacionalMéxico07738CDMXMéxico escuela superior de ingenieria Quimica e Industrias Extractivas Instituto Politécnico NacionalMéxico07738CDMXMéxico Universidad Juárez Autònoma de Tabasco DivisiònAcadémica Multidisciplinaria de Jalpa de MéndezRibera AltaJalpa de MéndezTabasco86205México

Al-doped ZnO(AZO) powders were prepared by using metal chloride precursors and the sol-gel technique. IR peaks observed at 1590 cm-1 and 1620 cm-1indicated the formation of metal chelate as a consequence of the addition of acetylacetone to the metal chloride solution. TG-DSC analysis of the AZO gels confirmed the formation of metal chelate as evidenced by the development of several weight loss peaks accompanied by the introduction of new endothermic peaks. The resulting AZO gels were annealed at 500, 600, and 800 ℃ to study the effect of annealing temperature. XRD and SEM results showed that crystallization of AZO gels takes place around 600 ℃. Hexagonal wurtzite structure was identified as the main phase for all the samples. In addition, small shift of the XRD(002) peak coupled with XPS results from the AZO powders confirmed the successful doping of the ZnO powders. Micron sized rod-like AZO powders were uniform in dimension and morphology and remained stable even at 800 ℃.

关键词： aluminum doped ZnO rod-like metal chloride sol gel acetylacetone

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Fuzzy Voice Coding with Significant Impulses Modeling and Redundant Waveform Recycling

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Communications and Network 2013年第1期5卷 50-56页

作者： Ismael Rosas Arriaga Juan C. García Infante J. Carlos Sánchez García Microelectronics department Escuela Superior de Ingeniería Mecánica y Eléctrica Culhuacán Ciudad de México México

This paper proposes a voice codification based on two algorithms that make the wave form codification in time domain. The first uses the significant impulse model (SIM), which has as a goal to operate as an endpoint detector and as a dawn sampling, through the detection and selection of the significant valleys and crests;the second algorithm, is a redundant wave-form recycler (RWR) that uses an architecture based on fuzzy logic with an accumulative memory. The fuzzy algorithm obtains the similitude grade between the redundant wave forms, this with the objective of save into an knowledge base the patterns, based on the no supervised learning and when there are into memory, automatically there will be used to identified their arrive respect to the input signal, substituting the input block by the correspondent pattern into memory. This decoding process is using the SIM interpolation with a memory in accordance to the RWR.

关键词： Coding Signal Processing Fuzzy Logic Algorithms Pattern Recognition

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Influence of oxidation of automatic transmission fluids (ATFs) and sliding distance on friction coefficients of a wet clutch in the running-in stage

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Friction 2021年第2期9卷 401-414页

作者： Leonardo Israel FARFAN-CABRERA Ezequiel Alberto GALLARDO-HERNÁNdeZ Manuel VITE-TORRES Jesús Gilberto GODÍNEZ-SALCEDO Tecnologico de Monterrey Escuela de Ingeniería y CienciasAve.Eugenio Garza Sada 2501Monterrey 64849México Instituto Politécnico Nacional SEPI-Escuela Superior de Ingeniería Mecánica y EléctricaUnidad ZacatencoGrupo de TribologíaCol.LindavistaCiudad de México 07738México Instituto Politécnico Nacional ESIQIEIPNCol.LindavistaCiudad de México 07738México

In this paper,the influence of oxidation of automatic transmission fluids(ATFs)and sliding distance on the friction coefficients of a wet clutch in approached running-in conditions was investigated.The ATFs were oxidized by a laboratory process approaching oxidation occurred in actual ATFs.Oxidation was evaluated by means of increase in carbonyl compounds and depletion of zinc dialkyldithiophosphates(ZDDPs)additives.Also,the changes in kinematic viscosity and viscosity index were evaluated.Pin-ondisk tests were conducted to replicate the actual sliding contact in a wet clutch.The pin specimens were cut from friction material composite plates and the disks were actual steel separators both from an automotive wet clutch.Friction coefficient, μ,was measured at progressive sliding velocity,ν,to obtain μ–νcurves at 26 and 100°C.Three μ–νtests were consecutively run using the same pair of specimens and oil.The cumulative sliding distance for each μ–νtest generated surface flattening using the oils.The friction coefficients of the wet clutch increased due to the ATFs oxidation meanwhile the dm/dv values decreased in most cases.It suggests that ATF oxidation can enhance torque capacity of the wet clutch,but it could reduce anti-shudder property.Progressive sliding distance improved the slopes in the μ–νresults using fresh ATFs meanwhile it generated a slope decrease by using aged ATFs.

关键词： wet clutch friction oil oxidation automatic transmission fluid(ATF)

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Stabilization and control of unstable first order linear delay systems

Stabilization and control of unstable first order linear del...

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2008建模、辨识与控制国际会议

作者： B.del-Muro-Cuellar J.F.Mrquez-Rubio M.Velasco-Villa J.lvarez-Ramirez Hector Puebla escuela superior de ingenieria mecnica y eléctrica Unidad Culhuacan Instituto Politécnico Nacional Universidad Autopnoma Metropolitana

This work considers the problem of stabilization and control of first order linear systems subject to input delay. As it is known, the stability analysis of this type of systems becomes difficult due

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detection of DC series arc in more electric aircraft power system based on optical spectrometry

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High Voltage 2020年第1期5卷 24-29页

作者： Jun Jiang Mingxin Zhao Zhe Wen Chaohai Zhang Ricardo Albarracín Center for More electric Aircraft Power System Nanjing University of Aeronautics and AstronauticsNanjing 211106People's Republic of China departamento de Ingeniería eléctrica ElectrónicaAutomática y Física AplicadaEscuela Técnica Superior de Ingeniería y Diseño IndustrialUniversidad Politécnica de MadridRonda de Valencia 328012 MadridSpain

Series arcing faults have been recognised as a hazardous phenomenon in the power system of more electric aircraft(MEA),especially with the increasing voltage level and power supply.Instead of the electrical method,the optical method can be used as an approach to detect arc fault with the advantages of fast response and immunity to electromagnetic interference.It is the basis of optical arc detection to determine the distribution spectrum range of direct current(DC)arc fault.Aiming at series arc optical detection in the MEA DC system,a DC series arc test platform was established to measure the series arc spectrum.The spectrum was disassembled though empirical mode decomposition to extract characteristic wavelengths of arc light and denoised by means of wavelet decomposition and reconstruction(wavelet transformation)to reduce equipment noise.To resolve the baseline drift,the baseline of the arc spectrum measured was calculated and corrected based on Savitzky−Golay.The experimental results indicate that there are several series arc characteristic spectra of the MEA DC system,including 309.3 and 324.5 nm in the ultraviolet range.Moreover,the arc spectrum with different metals,copper and aluminium,were contrasted,indicating the arc spectral behaviour is related to the melting/boiling point and chemical properties of the anode material.The measurement of the series arc spectrum makes it more effective to apply optical detection in the MEA discharging faults diagnosis.

关键词： power system series

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The Swirling Jet Generation Method and Its Effect on the Velocity Distribution

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Journal of mechanics Engineering and Automation 2020年第1期10卷 16-26页

作者： Fernández Roque Tiburcio Correa Arredondo JoséArturo Mejía Carmona Alejandro Sandoval Lezama Jorge Vázquez Flores JoséFélix Tiburcio Fernández Roque Instituto Politécnico Nacional Escuela Superior de Ingeniería Mecánica y Eléctrica Unidad TicomanAv.Ticoman No.600Col.San JoséTicomanAlcaldía Gustavo A.MaderoC.P.07340 México DFMéxico 不详

The wing tip vortex has a great similarity with the swirling jets.Since these are generated of a simpler and more economic form in a laboratory,it is relevant to determine which the best method is for the generation of the swirling jet.In this paper,the velocity distribution obtained experimentally with the method of generation here proposed,which consists of the employment of an axial fan without stators,is compared with the velocity distribution of swirling jets generated with three different methods.It is observed that the velocity distribution obtained with the proposed method is similar with one of the methods found in the references,which uses fixed blades guides at the entry of the pipe.The proposed method is suitable for the generation of the swirling jet and it is considered that it is simpler and more economic to use blades fixed guides.

关键词： Swirling jet velocity distribution swirl intensity wingtip vortex tangential velocity

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Coherent States for the Two-Dimensional Dirac-Moshinsky Oscillator Coupled to an External Magnetic Field

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理论物理通讯：英文版 2015年第3期63卷 271-274页

作者： D.Ojeda-Guillen R.D.Mota V.D.Granados escuela superior de Física y Matemáticas Instituto Politécnico NacionalEd.9Unidad Profesional Adolfo López MateosC.P.07738México D.F.Mexico escuela superior de Ingeniería mecánica y eléctrica Unidad CulhuacánInstituto Politécnico NacionalAv.Santa Ana No.1000Col.San Francisco CulhuacánDelegación CoyoacánC.P.04430Mexico D.F.Mexico

We show that the(2+l)-dimensional Dirac-Moshinsky oscillator coupled to an externa/ magnetic field can be treated algebraically with the SU(1,1) group theory and its group basis.We use the su(1,1) irreducible representation theory to find the energy spectrum and the eigenfunctions.Also,with the su(1,1) group basis we construct the relativistic coherent states in a closed form for this problem.

关键词：振荡器狄拉克相干态外部磁场连接二维本征函数表示理论

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Compatibility of early natural enemy introductions in commercial pepper and tomato greenhouses with repeated pesticide applications

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Insect Science 2020年第5期27卷 1111-1124页

作者： Beatriz Dader Ignacio Colomer Angeles Adan Pilar Medina elisa Vinuela Unidad de Proteccion de Cultivos Escuela Tecnica Superior de Ingenieria AgronomicaAlimentaria y de Biosistemas(ETSIAAB)Universidad Polit^cnica de Madrid(UPM)MadridSpain departamento de ingenieria Rural Escuela Superior de IngenieriaUniversidad de AlmeriaAlmeriaSpain

Successful integrated pest management in protected crops implies an evalu-ation of the compatibility of pesticides and natural enemies(NE),as control strategies that only rely on one tactic can fail when pest populations exceed NE activity or pests become resistant to pesticides.Nowadays in Almeria(Spain),growers release NE prior to transplanting or early in the crop cycle to favor their settlement before pest arrival because this improves biocontrol efficacy,although it extends pesticide exposure periods.The pur-pose of this research was to evaluate the compatibility of two applications of pesticides with key NE in 2-year trials inside tomato and sweet pepper commercial greenhouses:Nesidiocoris tenuis(Reuter)(Hemiptera:Miridae),Orius laevigatus(Say)(Hemiptera:Anthocoridae)and Amblyseius swirskii(Athias-Henriot)(Acari:Phytoseidac).In tomato,flubendiamide and chlorantraniliprole(IOBC category 1)were compatible with N.tenuis,but chlorpyrifos.:methyl and spinosad(IOBC categories 2-3),which efectively reduced Tiuta absoluta(Meyrick)(Lepidoptera:Gelechidae)density,compromised its predatory activity.In sweet pepper,chlorantraniliprole(IOBC category 1)was the only pesticide compatible with O.laevigatus while chlorantraniliprole,emamectin benzoate,spirote-tramat and pymetrozine were harmless(IOBC category 1)to Amblyseius swirskii,and sulfoxaflor slightly harmful(IOBC category 2)to this phytoseiid predator.

关键词： Amblyseius swirskii chemical control Frankliniella occidentalis Nesidiocoris tenuis Orius laevigatus Tuta absoluta

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