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Mapping of cropland,cropping patterns and crop types by combining optical remote sensing images with decision tree classifier and random forest

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Geo-Spatial Information Science 2023年第3期26卷 302-320页

作者： Aqil Tariq Jianguo Yan alexandre S.Gagnon Mobushir Riaz Khan Faisal Mumtaz State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina School of Biological and Environmental Sciences Liverpool John Moores UniversityLiverpoolUK School of Environmental Science Charles Sturt UniversityAlburyAustralia State Key Laboratory of Remote Sensing Sciences Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences(UCAS) BeijingChina

Mapping and monitoring the distribution of croplands and crop types support policymakers and international organizations by reducing the risks to food security,notably from climate change and,for that purpose,remote sensing is routinely ***,identifying specific crop types,cropland,and cropping patterns using space-based observations is challenging because different crop types and cropping patterns have similarity spectral *** study applied a methodology to identify cropland and specific crop types,including tobacco,wheat,barley,and gram,as well as the following cropping patterns:wheat-tobacco,wheat-gram,wheat-barley,and wheat-maize,which are common in Gujranwala District,Pakistan,the study *** methodology consists of combining optical remote sensing images from Sentinel-2 and Landsat-8 with Machine Learning(ML)methods,namely a Decision Tree Classifier(DTC)and a Random Forest(RF)*** best time-periods for differentiating cropland from other land cover types were identified,and then Sentinel-2 and Landsat 8 NDVI-based time-series were linked to phenological parameters to determine the different crop types and cropping patterns over the study region using their temporal indices and ML *** methodology was subsequently evaluated using Landsat images,crop statistical data for 2020 and 2021,and field data on cropping *** results highlight the high level of accuracy of the methodological approach presented using Sentinel-2 and Landsat-8 images,together with ML techniques,for mapping not only the distribution of cropland,but also crop types and cropping patterns when validated at the county *** results reveal that this methodology has benefits for monitoring and evaluating food security in Pakistan,adding to the evidence base of other studies on the use of remote sensing to identify crop types and cropping patterns in other countries.

关键词： Sentinel-2 Random Forest cropland crop types cropping patterns Decision Tree Classifier

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Design and Manufacturing of A Ball Catcher’s Robot

Design and Manufacturing of A Ball Catcher’s Robot

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作者： CHEVALIER alexandre 东南大学

学位级别：硕士

The purpose of the thesis was to build an Arduino-based robot that is able to catch tennis balls on an unknown area without the help of its *** paper describes the whole project,from the design to the realization with the tests and *** functioning of the robot was inspired from the automated vacuum cleaners,and the ball catcher system from construction machine,It means the ball catcher system is easy to remove,and could be replaced by another tool in order to realize other *** and electrical studies were realized to choose the *** the algorithms,probabilities studies and simulations results were made to determine the best way to cover with efficiency a large area by moving *** develop the algorithm,some random walks path finding,such as random walk,spiral,snaking and wall follow algorithms were compared,and simulated on Webots to select the best one to *** mathematics results obtained on Wolfram Mathematica also describe more deeply the random walk algorithm,depending on the size of the *** theorical obtained results showed that a random walker will easily cover all the sites for a small *** is confirmed with the realized tests with our ***,the implemented algorithm is based on a random walk,using ultrasonic,choc and infrared sensors to get information on the *** a larger lattice,the results showed that the algorithm meet some issues to visit al the sites and is visiting some sites more than *** the tests,the reliability of the ball catcher system was *** chosen solution has evolved during the project but is still not completely *** study concludes that the random walk algorithm has a limited range to conserves a good *** larger areas,upgrades need to be conducted,such as adding encoders,or change the microcontroller for a more powerful one,in order to do execute image *** the ball catcher,a system that doesn’t need activation,but

关键词：接球机器人壁面跟踪随机游走器红外传感器

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Structural metamaterials with negative mechanical/thermomechanical indices: A review

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Progress in Natural Science:Materials International 2021年第6期31卷 801-808页

作者： Jo?o O.Cardoso Jo?o Paulo Borges alexandre Velhinho CENIMAT/i3N Departamento de Ciência dos Materiais Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa

Structural metamaterials presenting negative values of one or more mechanical and thermomechanical indices–namely the Poisson's ratio, the linear compressibility, and the coefficient of thermal expansion – are the promising candidates to the applications in many fields, ranging from precision mechanics to biomedical devices or energy absorption. Although scattered mentions may be found in the literature since the late eighties of 20th century, the systematic research efforts concerning these materials became effective much later. The present work is to review the main scientific contributions to the topic in the last five years. This paper first deals with those metamaterials showing a single negative index, and then proceeds to analyze the much less frequent instances of coupled negative indices, with emphasis on the so-called anepectic case, which exhibits an unusual thermomechanical response.

关键词： Mechanical and thermomechanical metamaterials Auxetic Anepectic Negative Poisson's ratio Negative thermal expansion Negative linear compressibility

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Carbonates and organic matter in soils characterized by reflected energy from 350-25000 nm wavelength

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Journal of Mountain Science 2020年第7期17卷 1636-1651页

作者： Najmeh ASGARI Shamsollah AYOUBI Jose alexandre Melo DEMATTê AndréCarnieletto DOTTO Department of Soil Science College of AgricultureIsfahan University of Technology841156-83111IsfahanIran Department of Soil Science College of Agriculture Luiz de QueirózAv.Pádua Dias11CEP 13418-900PiracicabaSão PauloBrazil

The soil carbon pool which is the sum of soil organic carbon(SOC)and soil inorganic carbon(SIC)is the second largest active store of carbon after the oceans and it is an important component of the global carbon ***,accurate estimation of SOC and SIC as important carbon reservoirs in terrestrial ecosystems using fast,inexpensive and non-destructive methods is crucial for planning different climate change *** aim of the current research was to examine the effectiveness of Vis-NIR(visible and near-infrared spectroscopy:350-2500 nm)and MIR(mid-infrared spectroscopy:4000-400 cm-1)to characterize and estimate soil organic matter(SOM)and carbonates as main components of soil carbon stocks in Juneqan,Charmahal va Bakhtiari,*** do so,a total of 548 soil samples from this area were collected(October 2015)and analyzed in laboratory(August 2017).In order to develop models capable of predicting SOM and carbonates content,seven spectral preprocessing methods comprising Absorbance(Abs),De-trending(Det),Continuum removal(CR),Savitzky-Golay derivatives(SGD),standard normal variate transformation(SNV),multiplicative scatter correction(MSC)and Normalization by range(NBR)were conducted along with five multivariate methods including Random Forest(RF),Partial Least-Squares Regression(PLSR),Artificial Neural Network(ANN),Support Vector Machine(SVM)and Gaussian Process Regression(GPR).The content of carbonates caused spectral reflectance intensity to augment on several ranges of spectrum and strong absorption feature at 2338 nm in the Vis-NIR and 714,850,870,1796,2150 and 2510 cm-1 in the MIR spectra *** absorbed energy in several ranges,but also showed specific peaks in *** facts are associated with the structure of carbonates and SOM and its interaction with *** best combination of preprocessing and calibration models for carbonates quantification in Vis-NIR spectra was Det/PLSR(R2=0.74,RPD=2.19,RMSE=6.45).For SOM,it was Det/PLSR(R2=0.82,RPD=2.41,RM

关键词： Modeling Reflectance spectroscopy Soil analysis Preprocessing

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English and Chinese language frequency time series analysis

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Chinese Science Bulletin 2011年第34期56卷 3717-3722页

作者： DENG WeiBing WANG DuJuan LI Wei WANG Qiuping alexandre LUNAM UniversitY ISMANS Laboratoire de Physique Statistique et Systemes Complexes 44 Ave. Bartholdi 72000 Le Mans France Complexity Science Center Institute of Particle Physics Central China Normal University Wuhan 430079 China LUNAM UniversitY Universite du Maine LPEC UMR CNRS 6087 72085 Le Mans France Max-Planck-lnstitutefor Mathematics in the Sciences Leipzig 04103 Germany

English and Chinese language frequency time series (LFTS) were constructed based on an English and two Chinese novels. Methods of statistical hypothesis testing were adopted to test the nonlinear properties of the LFTS. Results suggest the series exhibited non-normal, auto-correlative, and stationary characteristics. Moreover, we found that LFTS follow the power law distributions, and thereby we investigated the fractal structure, long range correlation, and intermittency, which indicated the self-similarity features of LFTS, and also provided hints that human societies are likely to share some universal properties.

关键词：时间序列分析频率语言中文英文统计假设检验非线性特性长程相关性

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Transient leaf endophytes are the most active fungi in 1-year-old beech leaf litter

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Fungal Diversity 2018年第2期89卷 237-251页

作者： Marco alexandre Guerreiro Andreas Brachmann Dominik Begerow Derek Persoh AG Geobotany Faculty of Biology and BiotechnologyRuhrUniversitat BochumUniversitatsstraße 15044801 BochumGermany Faculty of Biology GeneticsLudwig-MaximiliansUniversity MunichGroßhaderner Straße 2-482152 Planegg-MartinsriedGermany

The ecological significance of fungi occurring asymptomatically inside living plant leaves is poorly *** the broad saprotrophic potential of many endophytic fungi,we hypothesized that they persist in decaying litter for an extended period of time after leaf *** assemblages were assessed by highthroughput sequencing in autumn leaves of beech(Fagus sylvatica)and in the corresponding leaf litter in 388 samples from 22 beech forest plots in three widely distant regions of Germany.A considerable proportion of the leafendophytic fungi was also found in 1-year-old ***occurrence networks revealed that the fungi formed unstructured assemblages inside the living leaves,rather than well-structured *** endophytic fungi constituted an integral part of the fungal litter community and were by far the most active fungi in 1-year-old *** therefore consider these endophytic occurrences to represent transient *** of the aboveground microbiome appears therefore to be closely connected to the process of litter *** the respective linked fungal habitat will facilitate predicting nutrient and carbon cycling and storage in forest ecosystems as well as elucidating the ecology of leaf microbiomes.

关键词： Endophytic fungi Litter fungi Plant microbiome Co-occurrence networks Litter decomposition Community assembly

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A new modeling approach of pressure waves at the inlet of internal combustion engines

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Journal of Thermal Science 2011年第2期20卷 181-188页

作者： David Chalet alexandre Mahé Jean-Franois Hétet Jérme Migaud Internal Combustion Engine Team Laboratory of Fluid Mechanics UMR CNRS 6598 Ecole Centrale de Nantes Advanced development Mann+Hummel France

This paper presents a new model used to describe the propagation of pressure waves at the inlet systems of internal combustion engine. In the first part, an analogy is made between the compressible air in a pipe and a mechanical ideal mass damper spring system. A new model is then presented and the parameters of this model are determined by the use of an experimental setup (shock tube test bench). With this model, a transfer function is defined in order to link directly the pressure and the air mass flow rate. In the second part, the model is included into an internal combustion engine simulation code. The results obtained with this code are compared to experimental ones which are measured on a one-cylinder engine test bench. This last one is driven by an electric motor in order to study only the effect of the pressure waves on the engine behavior. A good agreement is obtained between the experimental results and the numerical ones and the new approach is an alternative method for modeling the pressure wave phenomena in an internal combustion engine manifold.

关键词： gas dynamics pressure wave compressible flow frequency analysis transfer function internal combustion engine

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Phylogeny,identification and pathogenicity of the Botryosphaeriaceae associated with collar and root rot of the biofuel plant Jatropha curcas in Brazil,with a description of new species of Lasiodiplodia

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Fungal Diversity 2014年第4期67卷 231-247页

作者： alexandre Reis Machado Danilo Batista Pinho Olinto Liparini Pereira Departamento de Fitopatologia Universidade Federal de VicosaVicosa 36570-000Brazil

The global expansion of cultivation areas of Jatropha has contributed to the emergence of various *** in Brazil,the occurrence of a new disease has been reported that not only reduces the productivity but also causes the death of *** disease is associated with collar and root rot of *** morphological and phylogenetic studies(based on Internal Transcribed Spacers,β-tubulin and Translation Elongation Factor 1-αsequences),nine species of Botryosphaeriaceae were *** species include Lasiodiplodia egyptiacae,***,***,Macrophomina phaseolina,Neoscytalidium hyalinum and four Lasiodiplodia *** are proposed as new species(***,***,*** and ***).All the species in this study,except ***,are *** results show that root rot of physic nut plants is caused by complex *** study provides new information for future studies of disease management,quarantine programs and,especially,the development of resistant varieties for collar and root rot disease in ***.

关键词： Aetiology Botryosphaeriales Dothideomycetes Phylogeny Taxonomy Tropical fungi

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Application of varentropy as a measure of probabilistic uncertainty for complex networks

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Chinese Science Bulletin 2011年第34期56卷 3677-3682页

作者： JIANG Jian WANG Ru PEZERIL Michel WANG Qiuping alexandre Institut Superieur des Materiaux et Mecaniques Avarices 44 Avenue F.A. Bartholdi 72000 Le Mans France Complexity Science Center Institute of Particle Physics Central China Normal University Wuhan 430079 China LPEC Faculte des Sciences et Techniques Universite du Maine Ave. O. Messiaen 72035 Le Mans France College of Information Science and Engineering Huaqiao University Quanzhou 362021 China

Varentropy is used as a general measure of probabilistic uncertainty for a complex network, inspired by the first and second laws of thermodynamics, but not limited to the equilibrium system. By exploring the relationship between the varentropy of the scale free distribution and the exponent of power laws as well as network size, we get the optimal design of a scale-free network against random failures. The behaviors of varentropy and the Shannon entropy of double Pareto law degree distribution are analyzed to compare their usefulness. Our conclusion is that varentropy is suitable and reliable.

关键词：概率不确定性网络应用 Shannon熵无标度网络第二定律平衡系统幂律指数网络规模

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Gate length dependent transport properties of in-plane core-shell nanowires with raised contacts

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Nano Research 2020年第1期13卷 61-66页

作者： alexandre Bucamp Christophe Coinon David Troadec Sylvie Lepilliet Gilles Patriarche Xavier Wallart Ludovic Desplanque Univ.Lille CNRSCentrale LilleYncréa ISENUniv.Polytechnique Hauts-de-FranceUMR 8520-IEMNF-59000LilleFrance C2N-UMR 9001 CNRS UniversitéParis-Sud-UniversitéParis-Saclay91120PalaiseauFrance

Three-dimensional(3D)nanoscale crystal shaping has become essential for the precise design of advanced electronic and quantum devices based on electrically gated *** this context,Ⅲ-Ⅴ semiconductor-based nanowires with low electron effective mass and strong spin-orbit coupling are particularly investigated because of their exceptional quantum transport properties and the good electrostatic control they *** the main challenges involved in the processing of these nanodevices are(i)the management of the gate stack which requires ex-situ passivation treatment to reduce the density of traps at the oxide/semiconductor interface,(ii)the ability to get good ohmic contacts for source and drain electrodes and(iii)the scalability and reliability of the process for the fabrication of complex architectures based on nanowire *** this paper,we show that selective area molecular beam epitaxy of in-plane InGaAs/InP core-shell nanowires with raised heavily doped source and drain contacts can address these different *** characterization of the devices down to 4 K reveals the positive impact of the InP shell on the gate electrostatic control and effective electron *** comparable to the best reported values for In(Ga)As nanostructures grown on InP,this latter is severely reduced for sub-100 nm channel highlighting remaining issue to reach the ballistic regime.

关键词： molecular beam epitaxy core-shell nanowire selective area growth effective electron mobility

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