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An Analysis of the Dynamic Behavior of Damaged Reinforced Concrete Bridges under Moving Vehicle Loads by Using the Moving Mesh Technique

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Structural Durability & Health Monitoring 2023年第6期17卷 457-483页

作者： Fabrizio Greco Paolo Lonetti arturo Pascuzzo Giulia Sansone Department of Civil Engineering University of CalabriaVia P.BucciCubo39BRendeCosenza87030Italy

This work proposes a numerical investigation on the effects of damage on the structural response of Reinforced Concrete(RC)bridge structures commonly adopted in highway and railway *** effective three-dimensional FE-based numerical model is developed to analyze the bridge’s structural response under several damage scenarios,including the effects of moving vehicle *** particular,the longitudinal and transversal beams are modeled through solid finite elements,while horizontal slabs are made of shell *** phenomena are also incorporated in the numerical model according to a smeared approach consistent with Continuum Damage Mechanics(CDM).In such a context,the proposed method utilizes an advanced and efficient computational strategy for reproducing Vehicle-Bridge Interaction(VBI)effects based on a moving mesh technique consistent with the Arbitrary Lagrangian-Eulerian(ALE)*** proposed model adopts a moving mesh interface for tracing the positions of the contact points between the vehicle’s wheels and the bridge *** modeling strategy avoids using extremely refined discretization for structural members,thus drastically reducing computational *** analyses in terms of damage scenarios are presented to verify how the presence of damage affects the natural frequencies of the structural *** addition,a comprehensive investigation regarding the response of the bridge under moving vehicles is developed,also providing results in terms of Dynamic Amplification Factor(DAFs)for typical design bridge variables.

关键词： Bridge structures moving mesh technique vehicle-bridge interaction dynamics damage mechanics dynamic amplification factors

Pacing profiles and tactical behaviors of elite runners

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Journal of Sport and Health Science 2021年第5期10卷 537-549页

作者： arturo Casado Brian Hanley Pedro Jimenez-Reyes Andrew Renfree Faculty of Health Sciences Isabel I UniversityBurgos 09003Spain Carnegie School of Sports Leeds Beckett UniversityLeeds LS63QSUK Centre for Sport Studies Rey Juan Carlos UniversityMadrid 28943Spain Institute of Sport and Exercise Science University of WorcesterWorcester WR26AJUK

The pacing behaviors used by elite athletes differ among individual sports,necessitating the study of sport-specific pacing ***,pacing behaviors adopted by elite runners differ depending on race ***“all-out”strategy,characterized by initial rapid acceleration and reduction in speed in the later stages,is observed during 100 m and 200 m events;400 m runners also display positive pacing patterns,which is characterized by a reduction in speed throughout the ***,800 m runners typically adopt a positive pacing strategy during paced“meet”***,during championship races,depending on the tactical approaches used by dominant athletes,pacing can be either positive or negative(characterized by an increase in speed throughout).A U-shaped pacing strategy(characterized by a faster start and end than during the middle part of the race)is evident during world record performances at meet races in 1500 m,5000 m,and 10,000 m *** a parabolic J-shaped pacing profile(in which the start is faster than the middle part of the race but is slower than the endspurt)can be observed during championship 1500 m races,a negative pacing strategy with microvariations of pace is adopted by 5000 m and 10,000 m runners in championship *** cross country and marathon championship races are characterized by a positive pacing strategy;whereas a U-shaped pacing strategy,which is the result of a fast endspurt,is adopted by 3000 m steeplechasers and half *** contrast,recent world record marathon performances have been characterized by even pacing,which emphasizes the differences between championship and meet races at distances longer than 800 *** reviewed suggest further recommendations for *** the whole race,800 m runners should avoid running wide on the *** turn,during major championship events,1500 m,5000 m,and 10,000 m runners should try to run close to the inside of the track as much as possible during t

关键词： Athletics Distance running Pacing Sprinting

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

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

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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

Biogeographic patterns of the myxomycete biota of the Americas using a parsimony analysis of endemicity

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Fungal Diversity 2013年第2期59卷 159-177页

作者： arturo Estrada-Torres Diana Wrigley de Basanta Carlos Lado Centro de Investigación en Ciencias Biológicas Universidad Autónoma de TlaxcalaApartado Postal 183Tlaxcala 90000 TlaxcalaMexico Real Jardín Botánico de Madrid CSIC Plaza de Murillo 228014MadridSpain

Myxomycetes are microorganisms frequently considered to be of cosmopolitan distribution,however as studies in unexplored areas have intensified,more information has become available on the patterns of distribution of these organisms,but no historical or cladistic biogeographic approaches have been applied to understand such *** this study a parsimony analysis of endemicity(PAE)was used in order to generate a preliminary hypothesis on the biogeographic relationships of 13 American areas in which a well-known myxomycete biota *** general terms the hypotheses of the relationship between the myxomycete assemblages of areas used in this study agree with those reported for other groups of *** appear to show that a historical-geographic pattern influences the distribution of myxomycetes as much as environmental *** main clades were found in the analysis,with the first one including the two subantarctic localities,the second one representing the South American transition zone and the last one including all the Neotropical and Nearctic areas,but arranged into two subclades,one with the arid areas and the other with the tropical and temperate humid *** clade or subclade in the cladogram is supported by the presence of several morphospecies,some of which appear to represent endemic species restricted to specific geographic *** results of this analysis are proposed as a working hypothesis that can perhaps be supported in the future with new data from other complementary regions of America or with more intense surveys in the areas already *** are inconsistent with the hypothesis of cosmopolitan distribution for these microorganisms,as they appear to indicate groups of species that are restricted to certain geographic areas,some of which may be endemic,such as those from the subantarctic forests of South America,those found exclusively in the South American arid areas or those that have been recently described from arid ar

关键词： Andean region Distribution patterns Myxomycetes Nearctic Neotropics Ubiquity theory

Robust flat filtering DSP based control of the boost converter

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Control Theory and Technology 2016年第3期14卷 224-236页

作者： Hebertt SIRA-RAMIREz arturo HERNANDEz-MENDEz Jesus LINARES-FLORES Alberto LUVIANO-JUAREz Department of Hectrical Engineering Mechatronics Section ClNVESTAV-IPN Av. IPN No. 2508 Col. San Pedro Zacatenco 07360 D.F. Mexico Mexico Universidad Tecnologica de la Mixteca Carretera a Acatlima Kin. 2.5 Huajuapan de Leon Oaxaca Mexico UPIITA-IPN D.F. Mexico Mexico

The article deals with the design and implementation of a flat filter tracking digital controller for a boost DC-DC power converter. A highly perturbed switched boost converter circuit is shown to be efficiently controlled, in a trajectory tracking task for its non-minimum phase output, by means of a suitable linear filter, here addressed as a flat filter. Flat filtering is a natural robust version of generalized proportional integral control （GPIC） by which the effects of arbitrary time varying exogenous disturbances, unknown endogenous nonlinearities and un-modeled dynamics can be jointly attenuated in a conceptually similar fashion to observer-based active disturbance rejection control （ADRC） and algebraic identification based model free control （MFC） but： a） without using extended state observers and b） respecting the original system order in a time-varying simplified model while avoiding algebraic estimation techniques. The proposed control technique based on the TMS320F28335 digital signal processor chip is tested by means of realistic simulations and experimental setup.

关键词： Flat filter DSP-implementation boost converter

Genes, emotions and gut microbiota:The next frontier for the gastroenterologist

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World Journal of Gastroenterology 2017年第17期23卷 3030-3042页

作者： arturo Panduro Ingrid Rivera-Iniguez Maricruz Sepulveda-Villegas Sonia Roman Department of Molecular Biology in Medicine Civil Hospital of Guadalajara“Fray Antonio Alcalde” Health Sciences Center University of Guadalajara

Most medical specialties including the field of gastroenterology are mainly aimed at treating diseases rather than preventing them. Genomic medicine studies the health/disease process based on the interaction of the human genes with the environment. The gastrointestinal(GI) system is an ideal model to analyze the interaction between our genes, emotions and the gut microbiota. Based on the current knowledge, this mini-review aims to provide an integrated synopsis of this interaction to achieve a better understanding of the GI disorders related to bad eating habits and stress-related disease. Since human beings are the result of an evolutionary process, many biological processes such as instincts, emotions and behavior are interconnected to guarantee survival. Nourishment is a physiological need triggered by the instinct of survival to satisfy the body's energy demands. The brain-gut axis comprises a tightly connected neuralneuroendocrine circuitry between the hunger-satiety center, the dopaminergic reward system involved in the pleasure of eating and the gut microbiota that regulates which food we eat and emotions. However, genetic variations and the consumption of high-sugar and high-fat diets have overridden this energy/pleasure neurocircuitry to the point of addiction of several foodstuffs. Consequently, a gut dysbiosis generates inflammation and a negative emotional state may lead to chronic diseases. Balancing this altered processes to regain health may involve personalized-medicine and genome-based strategies. Thus, an integrated approach based on the understanding of the gene-emotions-gut microbiota interaction is the next frontier that awaits the gastroenterologist to prevent and treat GI disorders associated with obesity and negative emotions.

关键词： Genes Emotions Brain reward system Gut microbiota Gastrointestinal disease Personalized medicine Genome-based nutrition Nutrigenetics Food decision-making Obesity

Guidelines for rational design of high-performance absorbents:A case study of zeolite adsorbents for emerging pollutants in water

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Green Energy & Environment 2017年第4期2卷 363-369页

作者： Xiaoxuan Wei Ya Wang arturo J.Hernndez-Maldonado zhongfang Chen Department of Chemistry Institute for Functional Nanomaterials University of Puerto Rico Rio Piedras Campus Department of Chemical Engineering Institute for Functional Nanomaterials University of Puerto Rico Mayagüez Campus

Rational design is important to achieve high-performance sorbents used to remove the contaminants of emerging concern(CECs) from ***, it is hard to propose effective design guidelines due to the lack of a clear understanding of the interaction mechanisms. By means of systematic quantum chemical computations, as a case study, we investigated the interactions between zeolite X/M^(n+)-zeolite X(Si/Al=1,M^(n+)=Cu^(2+) and Ni^(2+)) and three commonly used CECs(namely salicylic acid, carbamazepine and ciprofloxacin) in water to clarify the adsorption mechanisms. Our computations found that anionic salicylic acid cannot be adsorbed by neither zeolite X nor M^(n+)-zeolite X in neutral water due to the high electrostatic repulsion. In comparison, carbamazepine and ciprofloxacin have favorable binding energies with both zeolite X and M^(n+)-zeolite X, and their interactions with M^(n+)-zeolite X are stronger due to the joint effects of H-bond, metal complexation and electrostatic interaction. The adsorption loading of ciprofloxacin, which has a large molecular size, on M^(n+)-zeolite X is limited due to the steric hindrance. In general, steric hindrance, electrostatic interaction, H-bond and metal complexation are dominant factors for the examined systems in this study. Thus, for the design of high-performance absorbing materials, we should fully consider the molecular properties of pollutants(molecular size, surface electrostatic potential and atomic type, etc.), and properly enhance the favorable effects and avoid the unfavorable factors as much as possible under the guidance of the interaction mechanisms.

关键词： Adsorption mechanism Adsorbent design guidelines Quantum chemical computations Contaminants of emerging concern zeolite X

Resistance to the Whitefly Aleurotrachelus socialis(Hemiptera:Aleyrodidae) and SSR Marker Identification in Advanced Populations of the Hybrid Manihot esculenta *** flabellifolia

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Journal of Integrative Agriculture 2013年第12期12卷 2217-2228页

作者： arturo Carabalí James Montoya-Lerma Anthony C Belloti Martin Fregene Gerardo Gallego Deparment of Biology Universidad del Valle International Center of Tropical Agriculture (CIAT)

Genes resistant to Aleurotrachelus socialis were transferred to the F 1 from the interspecific hybrid wild species of Manihot flabellifolia to *** and two advanced generations of backcrosses（BC 1 and BC 2）.We characterized the resistance of *** transferred to BC 2 parents（CW67-160,CW67-130,CW67-44）,MTAI-8（BC 1）,resistant（CMB9B-73） and susceptible（CMB9B-104） genotypes from contrasting pools,and resistant（MEcu-72） and susceptible（CMC-40） *** demography and biology were *** molecular markers associated with a phenotypic response of plant resistance were detected in segregating populations（BC 2）.Results showed that although female survival time was similar on all hosts,the lowest averages of longevity,fecundity and oviposition rate were observed in the resistant control MEcu- 72,only being significantly similar to the parent *** the BC 1 and BC 2 populations were compared,it was found that *** fecundity was eight times lower on CMB9B-73 progeny than on CW67-130,expressing the highest levels of resistance to the *** genotypes of CMB9A and CMB9B family had the best segregation.A total of 486 microsatellite primers were evaluated using bulked segregant analysis（BSA）,11 showed polymorphism between the contrasting pools and only one showed significant differences between resistant and susceptible *** conclusion,fecundity was the parameter that impacted most on the intrinsic rate of *** population growth.

关键词： cassava wild parents interspecific hybrids whitefly resistance BSA