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Environmental Factors that Affect Primary Plant Succession Trajectories on Lahars(Popocatépetl Volcano,Mexico)

Journal of Mountain Science 2015年第5期12卷 1254-1266页

作者： garcia-romero arturo ALANIS-ANAYA Rocío Marisol MUNOZ-JIMENEZ Julio Departamento de Geografía Física Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Laboratorio de Análisis Geoespacial Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Departamento de A.G.R.y Geografía Física Facultad de Geografía e HistoriaUniversidad Complutense de Madrid.Calle Profesor Aranguren s/nCiudad Universitaria28040MadridSpain

The earliest stages of plant succession on severely disturbed sites usually follow highly unpredictable trajectories. However, in the Popocatépetl volcano area(50 km SE of Mexico City),the development of physiognomically distinct primary plant communities suggests the occurrence of various successional trajectories only 10 years after the onset of colonization of a temperate forest on lahars. To characterize plant communities and determine the environmental factors that drive the differences observed between plant communities and their successional trajectories, we monitored 64 circular sample plots(3.14 m2) from 2002 to 2011. We examined the plant communities' composition and structure in terms of their species richness and abundance, plant cover, and maximum stem height,and recorded 13 environmental factors related to the volcanic deposit characteristics, microclimate, soil,flow dynamics and gravitational processes. A cluster analysis of the species abundance data showed that,by 2011, six plant community types(CT's) had established, including grasslands, and open, dense and very dense shrub lands. As these communities developed over the same period of time and within the same overall ecosystem, then these plant community types were interpreted as different stages of the same successional trajectory. Two sequential main stages that drive regeneration were identified from this successional trajectory: a) the first four years are characterized by a steady increase in species richness and physiognomic development(plant size and coverage), mostly dominated by Baccharis conferta, Eupatorium glabratum and Senecio barbajohannis; b) from the sixth year onwards, a continued increase in the abundance of those same species led to the development of the dense shrubland *** in the availability of soil resources and disturbances linked to recent lahar flows were the main factors accounting for such differences.

关键词： Ecosystem regeneration Plantcolonization Primary succession Temperate forest Light exposure Elevation Soil Slope aspect

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Fused empirical mode decomposition and wavelets for locating combined damage in a truss-type structure through vibration analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第9期14卷 615-630页

作者： arturo garcia-PEREZ Juan P. AMEZQUITA-SANCHEZ Aurelio DOMINGUEZ-GONZALEZ Ramin SEDAGHATI Roque OSORNIO-RIOS Rene J. romero-TRONCOSO HSPdigital-CA Telematica-Procesamiento Digital de Se ales DICIS Universidad de Guanajuato Carr. Salamanca-Valle km 3.5+1.8 Palo Blanco 36885 Salamanca Gto. Mexico HSPdigital CA Mecatronica Facultad de Ingeniería Campus San Juan del Río Universidad Autonoma de Queretaro Moctezuma 249 Col. San Cayetano 76807 San Juan del Río Qro. Mexico Department of Mechanical and Industrial Engineering Concordia University1455 de Maisonneuve Boulevard West Montreal QC H3G 1M8 Canada

Structural health monitoring (SHM) is a relevant topic for civil systems and involves the monitoring, data processing and interpretation to evaluate the condition of a structure, in order to detect damage. In real structures, two or more sites or types of damage can be present at the same time. It has been shown that one kind of damaged condition can interfere with the detection of another kind of damage, leading to an incorrect assessment about the structure condition. Identifying combined damage on structures still represents a challenge for condition monitoring, because the reliable identification of a combined damaged condition is a difficult task. Thus, this work presents a fusion of methodologies, where a single wavelet-packet and the empirical mode decomposition (EMD) method are combined with artificial neural networks (ANNs) for the automated and online identification-location of single or multiple-combined damage in a scaled model of a five-bay truss-type structure. Results showed that the proposed methodology is very efficient and reliable for identifying and locating the three kinds of damage, as well as their combinations. Therefore, this methodology could be applied to detection-location of damage in real truss-type structures, which would help to improve the characteristics and life span of real structures.

关键词： Truss structure Vibration Spectral analysis Wavelet packet transform Empirical mode decomposition Artificialneural network (ANN)

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Landform Instability and Land-use Dynamics in Tropical High Mountains, Central Mexico

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Journal of Mountain Science 2012年第3期9卷 414-430页

作者： GARCíA-romero arturo ACEVES-QUESADA José Fernando ARREDONDO-LEóN Carlos Departamento de Geografía Física Instituto de Geografía Universidad Nacional Autónoma de México. Circuito exterior s/n Ciudad Universitaria 04510 Mexico Distrito Federal Mexico Unidad Académica de Estudios Regionales de la Coordinación de Humanidades Universidad Nacional Autónoma de México

This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the Mexican Volcanic Belt mountain range (central Mexico), currently affected by substantial changes in land use and deforestation. A landform map was produced, in addition to seven attribute maps - altimetry, drainage density, slope, relief energy, potential erosion, geology and tectonics - which were considered as factors for determining landform instability through Multi-criteria Evaluation Analysis. Likewise, the direction and rhythm of land-use dynamics were analyzed in four dates - between 1976 and 2000 - and cross tabulations were made between them, in order to analyze the trends and processes of land-use dynamics. Afterwards, the databases obtained were cross tabulated with the landform variables to derive areas, percentages and correlation indices. In the study area, high-instability landforms are associated with most ancient volcanic and sedimentary landforms, where high altitude, drainage density, slope and potential to develop gravitational and fluvial processes are the major factors favouring a land-use pattern, dominated by the conservation of extensive forest land, abandonment of human land use and regeneration of disturbed areas. In contrast, low-instability landforms correspond to alluvial plains and lava hills covered by pyroclasts, where low potential erosion to develop fluvial processes, added to water and soil availability and accessibility, have favoured a land-use pattern dominated by the expansion of agroforestry plantations and human settlements, showing a marked trend towards either intensification or permanence of the current land use and with little abandonment and regeneration.

关键词： Landform instability Multi-criteriaEvaluation Analysis Land-use change and processes Tuxpan River Basin

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A Mean Curvature Regularized Based Model for Demodulating Phase Maps from Fringe Patterns

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Communications in Computational Physics 2018年第6期24卷 27-43页

作者： Carlos Brito-Loeza Ricardo Legarda-Saenz arturo Espinosa-romero Anabel Martin-Gonzalez CLIR at Facultad de Matematicas Universidad Autonoma de YucatanMexico

We introduce a variationalmethod for demodulating phasemaps fromfringe *** newmethod is based on themean curvature of the level sets of the phase surface that is used for *** performance of the method is illustrated w... 详细信息

关键词： Fringe analysis interferometry high-order regularization variational models

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Fertirrigation with Low-Pressure Multi-Gate Irrigation Systems in Sugarcane Agroecosystems:A Review

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Pedosphere 2019年第1期29卷 1-11页

作者： arturo garcia-SALDANA Cesareo LANDEROS-SANCHEZ Maria del Refugio CASTANEDA-CHAVEZ Juan Pablo MARTINEZ-DAVILA arturo PEREZ-VAZQUEZ Eugenio CARRILLO-AVILA Postgraduate College Campus Veracruz Tepetates C.P.91674(Mexico) Technological Institute of Boca del Rio(ITBOCA) Boca del Rio C.P.94290(Mexico) Postgraduate College Campus Campeche Campeche C.P.24450(Mexico)

There are very few studies on the application of fertilizers through irrigation water(fertirrigation) using a multi-gate irrigation system in sugarcane AES. Through fertirrigation, the application of fertilizers can be simplified, and their distribution uniformity in sugarcane fields improved. This paper provides an overview of the state of the art regarding fertirrigation with multi-gate irrigation in sugarcane agroecosystems(AES). In order to systematize, organize, and discuss the scientific data on fertirrigation with low-pressure multi-gate irrigation systems in sugarcane AES, bibliographic material from the following full-text scientific journal databases was screened: the Elsevier Science Direct Freedom Collection, Springer Link, and the International Society for Horticultural Science. Next,a matrix of keywords was used to analyze the interrelationships among the available literature, current issues, and the recent *** conclude that development of fertirrigation technologies with low-pressure multi-gate irrigation is much needed.

关键词： climate change crop water requirement fertilizer application fertilizer distribution uniformity sugarcane industry water use efficiency

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Relativistic charged stellar modeling with a perfect fluid sphere

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Communications in Theoretical Physics 2023年第9期75卷 113-121页

作者： Joaquin Estevez-Delgado Joel arturo Rodríguez Ceballos Jorge Mauricio Paulin-Fuentes JoséVega Cabrera Antonio Rendón romero Facultad de Ciencias Físico Matemáticas de la Universidad Michoacana de San Nicolás de Hidalgo Edificio BCiudad UniversitariaMorelia MichoacánCP 58040Mexico Facultad de Químico Farmacobiología de la Universidad Michoacana de San Nicolás de Hidalgo Tzintzuntzan No.173Col.MatamorosMorelia MichoacánC.P.58240Mexico División Académica de Ciencias Básicas de la Universidad Juárez Autónoma de Tabasco Carretera Cunduacán-Jalpa Km.1Col.La Esmeralda86690CunduacánTabascoMexico Facultad de Ingenieria Mecanica de la Universidad Michoacana de San Nicolás de Hidalgo Edificio W Ciudad UniversitariaCP 58030Morelia MichoacánMexico

In this report we present the generalization of a solution to Einstein's equations with perfect fluid for the case of Einstein–Maxwell with perfect *** effect of the charge is reflected by a parameter,ν,and its interval is determined by the positivity condition from the pressure in the interior of the *** is shown that the solution is stable according to the Zeldovich criteria as well as in relation to the criteria of the adiabatic *** compactness,u=GM/c^(2)R,of this charged model is greater than it is for the chargeless case as a result of the effect of the presence of the *** allows it to represent stars with a high compactness,in particular a graphic analysis is presented for the star SAX J1808.4-3658 with mass M=1.435M_(⊙)and radius R=7.07 *** these data and employing the solution,we obtain that the total maximum charge for the star is Q=2.4085×10^(20)C.

关键词： general relativity exact solutions charged fluid stars models

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Emerging melt quality control solution technologies for aluminium melt

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China Foundry 2009年第4期6卷 358-365页

作者： arturo Pascual Foseco Foundry(China)Co. Ltd.2002 Leishing International Plaza1319 Yan'an RoadShanghaiChinaJr

The newly developed ＂MTS 1500＂ Melt Treatment System is performing the specifically required melt treatment operations like degassing, cleaning, modification and/or grain refinement by an automated process in one step and at the same location. This linked process is saving time, energy and metal losses allowing - by automated dosage of the melt treatment agents - the production of a consistent melt quality batch after batch. By linking the MTS Metal Treatment System with sensors operating on-line in the melt, i.e., with a hydrogen sensor ＂Alspek H＂, a fully automated control of parts of the process chain like degassing is possible. This technology does guarantee a pre-specified and documented melt quality in each melt treatment batch. Furthermore, to ensure that castings are consistent and predictable there is a growing realization that cdtical parameters such as metal cleanliness must be measured prior to casting. There exists accepted methods for measuring the cleanliness of an aluminum melt but these can be both slow and costly. A simple, rapid and meaningful method of measuring and bench marking the cleanliness of an aluminum melt has been developed to offer the foundry a practical method of measuring melt cleanliness. This paper shows the structure and performance of the integrated MTS melt treatment process and documents achieved melt quality standards after degassing, cleaning, modification and grain refinement operations under real foundry conditions. It also provides an insight on a melt cleanliness measuring device ＂Alspek MQ＂ to provide foundry men better tools in meeting the increasing quality and tighter specification demand from the industry.

关键词： melt quality aluminum casting melt treatment cleanliness measuring

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Introduction of Dr. Andrew V Schally

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Asian Journal of Andrology 2015年第6期17卷 923-924页

作者： arturo Mendoza-Valdes UROLOGO Hospital Medica Sur Puente dePiedra 150 T2-625 Col. Toriello Guerra Tlalpan14050Mexico DF.

Ifirst met Dr. Andrew V Schally （PhD, MDhc （Multi）, DSc, Distinguished Medical Research Scientist, U.S. Department of Veterans Affairs Professor of Pathology and Department of Medicine, Miller School of Medicine, University of Miami, Miami, Florida, USA） many years ago, probably around the beginning of the 1990＇s in one of his visits to Mexico City （Figure 1）. He has many friends in my country since some of the investigations that led to the development of the LHRH agonists were made in a couple of Mexican hospitals in collaboration with some outstanding Mexican physicians that I will mention later. In that time, I was the head of the Department of Urology of the Mexican National Cancer Institute and our Director, Dr. Jaime de la Garza, invited him for a meeting. I was surprised by his humbleness, intelligence and easy going personality, in spite of being a Nobel Prize scientist.

关键词： Introduction Andrew Schally

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An Approach to Design MIMO FO Controllers for Unstable Nonlinear Plants

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IEEE/CAA Journal of Automatica Sinica 2016年第3期3卷 338-344页

作者： arturo Rojas-Moreno IEEE Department of Electrical Engineering Universidad de Ingenieriay Tecnologia (www.utec.edu.pe)

This paper develops an approach to control unstable nonlinear multi-inputs multi-output(MIMO) square plants using MIMO fractional order(FO) controllers. The controller design uses the linear time invariant(LTI) state space representation of the nonlinear model of the plant and the diagonal closedloop transfer matrix(TM) function to ensure decoupling between inputs. Each element of the obtained MIMO controller could be either a transfer function(TF) or a gain. A TF is associated in turn with its corresponding FO TF. For example, a D(Derivative) TF is related to a FO TF of the form Dδ, δ =[0, 1]. Two applications were performed to validate the developed approach via experimentation: control of the angular positions of a manipulator, and control of the car and arm positions of a translational manipulator.

关键词： Fractional calculus modeling of nonlinear sys-tem control of manipulator multivariable decoupling multivari-able nonlinear system

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Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory, and fuzzy detection theory in regions of Mexico

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Frontiers in Energy 2019年第3期13卷 522-538页

作者： Pedro PONCE Therese PEFFER arturo MOLINA Tecnologico de Monterrey calle del puente 222 MexicoMexico CityNon-US/Non-Canadian 64849Mexico California Institute for Energy and Environment University of California BerkeleyBerkeleyCA 94720USA

It is well known that smart thermostats (STs) have become key devices in the implementation of smart homes;thus, they are considered as primary elements for the control of electrical energy consumption in households. Moreover, energy consumption is drastically affected when the end users select unsuitable STs or when they do not use the STs correctly. Furthermore, in future, Mexico will face serious electrical energy challenges that can be considerably resolved if the end users operate the STs in a correct manner. Hence, it is important to carry out an in-depth study and analysis on thermostats, by focusing on social aspects that influence the technological use and performance of the thermostats. This paper proposes the use of a signal detection theory (SDT), fuzzy detection theory (FDT), and chi-square (CS) test in order to understand the perceptions and beliefs of end users about the use of STs in Mexico. This paper extensively shows the perceptions and beliefs about the selected thermostats in Mexico. Besides, it presents an in-depth discussion on the cognitive perceptions and beliefs of end users. Moreover, it shows why the expectations of the end users about STs are not met. It also promotes the technological and social development of STs such that they are relatively more accepted in complex electrical grids such as smart grids.

关键词： thermostats perceptions beliefs signal detection theory (SDT) fuzzy signal detection theory (FSDT) chi-square (CS) test

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