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Microbial enzymatic stoichiometry and the acquisition of C, N,and P in soils under different land-use types in Braziliansemiarid

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Soil Ecology Letters 2023年第3期5卷 101-108页

作者： Erika Valente de medeiros Érica de Oliveira Silva Gustavo Pereira Duda Mario Andrade Lira Junior Uemeson Josédos Santos Claude Hammecker Diogo Paes da Costa Fabio Fernando araujo Arthur Prudêncio de araujo Pereira Lucas William Mendes Ademir Sergio Ferreira araujo Laboratory of Microbiology and Enzymology-LEMA Federal University of Agreste PernambucoGaranhuns 55292-270Brazil Federal Rural University of Pernambuco Rua Dom Manuel de Medeiross/nDois Irmãos52171-900RecifeBrazil Soil-Agrosystem-Hydrosystem Interaction Lab-LISAH Place Pierre Viala234060 MontpellierFrance Universidade do Oeste Paulista Presidente PrudenteSPBrazil Departamento de Ciência Do Solo Universidade Federal Do CearáFortalezaCEBrazil Center for Nuclear Energy in Agriculture University of Sao PauloPiracicabaSPBrazil Soil Quality Lab Agricultural Science CenterFederal University of PiauíTeresinaPI 60049-550Brazil

This study hypothesized that different land-use affect the microbial enzymatic stoichiometry and C-,N-,and P-acquisition in Brazilian semiarid ***,the enzymesβ-glucosidase(C-acquiring enzyme),urease(N-acquiring enzyme),and acid phosphatase(P-acquiring enzyme)were assessed in soil samples collected at 0−5 and 5−10 cm depth from a tropical dry forest,a protected area with Angico,a protected area with Ipê,scrub area,and an agricultural area with *** values of C-,N-,and P-acquiring enzymes were used to calculate the enzymatic C:N,C:P,and N:P *** values of C:P and N:P ratios were higher at 0−5 cm depth,while no significant variation,between soil depth,was observed for C:N *** values of C-and N-acquiring enzymes were higher at 0−5 cm in tropical dry forest areas and Angico forest,*** all land use types,the values of vectors L and A were higher than 1°and 45°,*** study showed that both land-use and soil depth influence the enzymatic stoichiometry,showing higher values of C-and N-acquiring enzymes in native and protected forests at soil surface.

关键词： C:N:P stoichiometry tropical forests soil depth Luvisols

Optimal distribution of active piezoelectric elements for noise attenuation in sandwich panels

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International Journal of Smart and Nano Materials 2020年第4期11卷 400-416页

作者： J.F.A.Madeira A.L.araujo IDMEC Instituto Superior TecnicoUniversidade de LisboaLisboaPortugal ADM ISELInstituto Politecnico de LisboaLisboaPortugal

In this paper,a multiobjective optimization approach for obtaining the optimal distribution of surface-bonded piezoelectric sensors and actua-tors for noise attenuation in sandwich panels is *** noise attenuation is achieved by using negative velocity feedback control with co-located sensors and *** control gains are also optimized in order to obtain the most efficient noise attenuation in a given frequency *** in-house implementation of a viscoelastic soft core sandwich plate finite element,including surface-bonded piezoelectric sensors and actuators with active control capabilities,is used for obtaining the frequency response of the *** sound transmission capability of the panels is evaluated using the radiated sound power,along with the Rayleigh integral approach,which is suitable for lightly coupled structural/acoustic *** Direct MultiSearch(DMS)optimization algorithm is used to minimize the added weight due to the piezoelectric material,minimizing also the number of required controllers and maximizing the noise *** total length of the radiated sound power curve is shown to be an effective measure of noise attenuation in a given frequency ***-off Pareto fronts and the obtained optimal configurations are presented and discussed.

关键词： Sandwich structures piezoelectricity viscoelasticity active damping multiobjective optimization

Modeling considerations in seismic assessment of RC bridges using state-of-practice structural analysis software tools

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Frontiers of Structural and Civil Engineering 2018年第1期12卷 109-124页

作者： Ricardo MONTEIRO Miguel araujo Raimundo DELGADO Mario o MARQUES School of Advanced Studies IUSS Pavia Italy Department of Civil Engineering Faculty of Engineering University of Porto Portugal

The increasing awareness of the general society toward the seismic safety of structures has led to more restrictive performance requirements hence, many times, to the need of using new and more accurate methods of analysis of structures. Among these, nonlinear static procedures are becoming, evermore, the preferred choice of the majority of design codes, as an alternative to complete nonlinear time-history analysis for seismic design and assessment of structures. The many available software tools should therefore be evaluated and well understood, in order to be easily and soundly employed by the practitioners. The study presented herein intends to contribute to this need by providing further insight with respect to the use of commonly employed structural analysis software tools in nonlinear analysis of bridge structures. A comparison between different nonlinear modeling assumptions is presented, together with the comparison with real experimental results. Furthermore, alternative adaptive pushover procedures are proposed and applied to a case study bridge, based on a generic plastic hinge model. The adopted structural analysis program proved to be accurate, yielding reliable estimates, both in terms of local plastic hinge behavior and global structural behavior.

关键词： nonlinear analysis pushover RC bridges structural modelling software

TiO_(2)/WO_(3)heterogeneous structures prepared by electrospinning and sintering steps:Characterization and analysis of the impedance variation to humidity

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Journal of Advanced Ceramics 2019年第2期8卷 238-246页

作者： Evando S.araujo Victor N.S.LEAO Research Group on Electrospinning and Nanotechnology Applications(GPEA-Nano) Department of Materials ScienceUniversidade Federal do Vale do Sao Francisco

Relative humidity(RH) is a critical environmental variable for transportation and storage of products and for the quality guarantee of several other production processes and services. Heterogeneous structures prepared from the selective semiconductor oxides may improve the sensitivity to humidity due to the better electronic and surface properties, when compared to pristine oxides. This work shows an alternative fabrication route for producing titanium dioxide/tungsten trioxide(TiO2/WO3) heterogeneous structures(by electrospinning and sintering) for potential application on the RH detection. The microstructural properties of the materials were analyzed by scanning electron microscopy(SEM), energy dispersive X-ray analysis(EDS), X-ray diffraction, and Raman spectroscopy. The electrical characterization of the structures was performed by electrical impedance spectroscopy in RH range of 10%–100%. Results indicated a p-to n-type conduction transition at around 30%–40% RH for all tested settings. The analysis of the impedance signature to humidity showed that the amount of fiber layers on the electrode and working temperature are important parameters to improve the humidity sensing of the TiO2/WO3 systems.

关键词： electrospinning heterogeneous structures preparation relative humidity semiconductors

Communities of saprobic fungi on leaf litter of Vismia guianensis in remnants of the Brazilian Atlantic Forest

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Journal of Forestry Research 2017年第1期28卷 163-172页

作者： Loise araujo Costa Luís Fernando Pascholati Gusmao Laboratorio de Micologia Av Transnordestina Departamentode Ciências BiológicasUniversidade Estadual de Feira deSantanas/nNovo HorizonteFeira de SantanaBA 44031-460Brazil

We examined the mycobiota associated with Vismia guianensis leaf litter in three Atlantic Forest remnants of Brazil＇ s semiarid region. Among the study sites, two remnants were protected forest reserves, whereas the third was influenced by major anthropogenic activities. Eighteen litter samples were collected in wet and dry seasons and were processed by particle filtration technique. A total of 4750 fungal isolates of 142 taxa were identified. Species richness was higher in litter samples collected during wet season. Nonmetric multidimensional scaling multivariate analysis showed differences in the composition of fungal communities among the sampling sites and the seasons. Analysis of similarity showed that the differences were statistically significant （R = 0.85; P = 0.0001）. Our findings revealed that spatial and temporal heterogeneity, and human activities had significant impacts on the saprobic fungi of V. guianensis leaf litter.

关键词： Biodiversity Conservation Seasonality Spatial heterogeneity Tropical fungi

SCIENCE OF WINNING SOCCER:EMERGENT PATTERN-FORMING DYNAMICS IN ASSOCIATION FOOTBALL

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Journal of Systems Science & Complexity 2013年第1期26卷 73-84页

作者： VILAR Luís araujo Duarte DAVIDS Keith BAR-YAM Yaneer Faculty of Physical Education and Sports Lusofona University of Humanities and Technologies Faculty of Human Kinetics Technical University of Lisbon SpertLab CIPERFaculty of Human KineticsTechnical University of Lisbon School of Human Movement Studies Queensland University of Technologies New England Complex Systems Institute

Quantitative analysis is increasingly being used in team sports to better understand performance in these stylized,delineated,complex social ***,the authors provide a first step toward understanding the pattern-forming dynamics that emerge from collective offensive and defensive behavior in team *** authors propose a novel method of analysis that captures how teams occupy sub-areas of the field as the ball changes *** authors use this method to analyze a game of association football(soccer) based upon a hypothesis that local player numerical dominance is key to defensive stability and offensive *** authors find that the teams consistently allocated more players than their opponents in sub-areas of play closer to their own *** is consistent with a predominantly defensive strategy intended to prevent yielding even a single *** authors also find differences between the two teams' strategies:while both adopted the same distribution of defensive,midfield,and attacking players(a 4:3:3 system of play),one team was significantly more effective in maintaining both defensive and offensive numerical dominance for defensive stability and offensive *** team indeed won the match with an advantage of one goal(2 to 1) but the analysis shows the advantage in play was more pervasive than the single goal victory would *** proposed focus on the local dynamics of team collective behavior is distinct from the traditional focus on individual player *** supports a broader view in which specific player abilities contribute within the context of the dynamics of multiplayer team coordination and coaching *** applying this complex system analysis to association football,the authors can understand how players' and teams' strategies result in successful and unsuccessful relationships between teammates and opponents in the area of play.

关键词： Collective behavior performance analysis team sports.

On the wavelet analysis of cutting forces for chatter identification in milling

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Advances in Manufacturing 2017年第2期5卷 130-142页

作者： Cesar Giovanni Cabrera Anna Carla araujo Daniel Alves Castello Department of Mechanical Engineering UniversidadeFederal do Rio de Janeiro Rio de Janeiro Brazil

Chatter vibrations in machining operations affect surface finishing and tool behaviour, particularly in the end-milling of aluminum parts for the aerospace industry. This paper presents a methodological approach to identify chatter vibrations during manufacturing processes. It relies on wavelet analyses of cutting force signals during milling operations. The cutting-force signal is first decomposed into an approximation/trend sub-signal and detailed subsignals, and it is then re-composed using modified subsignals to reduce measurement noise and strengthen the reference peak forces. The reconstruction of the cuttingforce signal is performed using a wavelet denoising pro- cedure based on a hard-thresholding method. Four experimental configurations were set with specific cutting parameters using a workpiece specifically designed to allow experiments with varying depths of cut. The experimental results indicate that resultant force peaks （after applying the threshold to the detailed sub-signals） are related to the presence of chatter, based on the increased correlation of such peaks and the surface roughness profiles, thereby reinforcing the applicability of the proposed method. The results can be used to control the online occurrence of chatter in end-milling processes, as the method does not depend on the knowledge of cutting geometry nor dynamic parameters.

关键词： Cutting force End milling Chatter Waveletfilter

On Second Order Degree of Graphs

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Acta Mathematica Sinica,English Series 2012年第1期28卷 171-182页

作者： Gabriela araujo-PARDO Camino BALBUENA Mika OLSEN Pilar VALENCIA Instituto de Matemáticas rea de la Investigación CientíficaUniversidad Nacional Autónoma de MxicoCircuito ExteriorCiudad UniversitariaCoyoacan04510 MxicoD.F.Mxico Departament de Matemàtica Aplicada III Universitat Politècnica de CatalunyaC/Jordi Girona 1-3(Edifici C2Despatx 302)08034-BarcelonaSpain Departamento de Matemáticas Aplicadas y Sistemas Universidad Autónoma MetropolitanaCalle Artificios 402o pisoCol.Hidalgo Delegación lvaro Obregón01120 Mxico D.F.Mxico

Given a vertex v of a graph G the second order degree of v denoted as d2（v） is defined as the number of vertices at distance 2 from v. In this paper we address the following question： What axe the sufficient conditions for a graph to have a vertex v such that d2（v） ≥ d（v）, where d（v） denotes the degree of v？ Among other results, every graph of minimum degree exactly 2, except four graphs, is shown to have a vertex of second order degree as large as its own degree. Moreover, every K4^--free graph or every maximal planar graph is shown to have a vertex v such that d2（v） ≥ d（v）. Other sufficient conditions on graphs for guaranteeing this property axe also proved.

关键词： Second order degree K4^-free graph planar graphs

Yet Another Intelligent Code-Generating System： A Flexible and Low-Cost Solution

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Journal of Computer Science & Technology 2018年第5期33卷 940-965页

作者： Joao Fabricio Filho Luis Gustavo araujo Rodriguez Anderson Faustino da Silva Department of Informatics State University of Maringd Maringd-PR 87020-900 Brazil Federal University of Technology -- Parand Campo Mourao-PR 87301-899 Brazil

Modern compilers apply various code transformation algorithms to improve the quality of the target code. However, a complex problem is to determine which transformation algorithms must be utilized. This is difficult because of three reasons： a number of transformation algorithms, various combination possibilities, and several configuration possibil- ities. Over the last few years, various intelligent systems were presented in the literature. The goal of these systems is to search for transformation algorithms and thus apply them to a certain program. This paper proposes a flexible, low-cost and intelligent system capable of identifying transformation algorithms for an input program, considering the program＇s specific features. This system is flexible for parameterization selection and has a low-computational cost. In addition, it has the capability to maximize the exploration of available computational resources. The system was implemented under the Low Level Virtual Machine infrastructure and the results indicate that it is capable of exceeding, up to 21.36%, performance reached by other systems. In addition, it achieved an average improvement of up to 17.72% over the most aggressive compiler optimization level of the Low Level Virtual Machine infrastructure.

关键词： compiler code transformation iterative compilation knowledge representation machine learning