Search results for "square"

showing 10 items of 1317 documents

Detecting crop water status in mature olive orchards using vegetation spectral measurements.

2014

Full spectral measurements (350–2500 nm) at tree canopy and leaf levels and the corresponding leaf water potentials (LWP) were acquired in an olive grove of Sicily, at different hours of the day, during summer season 2011. The main objective of the work was to assess, on the basis of the experimental data-set, two different approaches to detect crop water status in terms of LWP. Specifically, using existing families of Vegetation Indices (VIs) and applying Partial Least Squares Regression (PLSR) were optimised and tested. The results indicated that a satisfactory estimation of LWP at tree canopy and leaf levels can be obtained using vegetation indices based on the near infrared–shortwave in…

HydrologyLeaf Water PotentialTree canopySpectral indexMean squared errorMoistureSoil ScienceCrop Water StatuVegetationCropSpectroradiometerControl and Systems EngineeringPartial least squares regressionSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliLeaf water potential; Olive tree; Field SpectroscopyAgronomy and Crop ScienceOlive treeSpectroscopyField SpectroscopyFood ScienceRemote sensingMathematics
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Modeling soil cation exchange capacity in multiple countries

2017

Abstract Cation exchange capacity (CEC), as an important indicator for soil quality, represents soil's ability to hold positively charged ions. We attempted to predict CEC using different statistical methods including monotone analysis of variance (MONANOVA), artificial neural networks (ANNs), principal components regressions (PCR), and particle swarm optimization (PSO) in order to compare the utility of these approaches and identify the best predictor. We analyzed 170 soil samples from four different nations (USA, Spain, Iran and Iraq) under three land uses (agriculture, pasture, and forest). Seventy percent of the samples (120 samples) were selected as the calibration set and the remainin…

HydrologyMean squared errorSoil test04 agricultural and veterinary sciences010501 environmental sciences01 natural sciencesSoil qualityPedotransfer functionMultivariate analysis of variancePrincipal component analysisStatistics040103 agronomy & agricultureCation-exchange capacity0401 agriculture forestry and fisheriesSoil fertility0105 earth and related environmental sciencesEarth-Surface ProcessesMathematicsEcologia dels sòls
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Assessing the performance of thermal inertia and Hydrus models to estimate surface soil water content

2017

The knowledge of soil water content (SWC) dynamics in the upper soil layer is important for several hydrological processes. Due to the difficulty of assessing the spatial and temporal SWC dynamics in the field, some model-based approaches have been proposed during the last decade. The main objective of this work was to assess the performance of two approaches to estimate SWC in the upper soil layer under field conditions: the physically-based thermal inertia and the Hydrus model. Their validity was firstly assessed under controlled laboratory conditions. Thermal inertia was firstly validated in laboratory conditions using the transient line heat source (TLHS) method. Then, it was applied in…

Hydrus010504 meteorology & atmospheric sciencesMean squared error0208 environmental biotechnologyHydrus numerical modelSoil science02 engineering and technologyHydrus numerical model; Soil thermal inertia; Soil water content; Sparse vegetation; Applied MathematicsThermal diffusivitySoil water content01 natural scienceslcsh:TechnologySparse vegetationlcsh:ChemistrySoil thermal propertiesSettore AGR/08 - Idraulica Agraria E Sistemazioni Idraulico-ForestaliGeneral Materials ScienceTime domainSoil thermal inertiaReflectometryInstrumentationlcsh:QH301-705.50105 earth and related environmental sciencesRemote sensingFluid Flow and Transfer Processeslcsh:TProcess Chemistry and TechnologyApplied MathematicsSettore ICAR/02 - Costruzioni Idrauliche E Marittime E IdrologiaGeneral EngineeringRanginglcsh:QC1-999020801 environmental engineeringComputer Science Applicationslcsh:Biology (General)lcsh:QD1-999lcsh:TA1-2040Soil waterEnvironmental sciencelcsh:Engineering (General). Civil engineering (General)lcsh:Physicssoil water content; soil thermal inertia; Hydrus numerical model; sparse vegetationSettore ICAR/06 - Topografia E Cartografia
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In the Shadows of a hypergraph: looking for associated primes of powers of squarefree monomial ideals

2018

The aim of this paper is to study the associated primes of powers of square-free monomial ideals. Each square-free monomial ideal corresponds uniquely to a finite simple hypergraph via the cover ideal construction, and vice versa. Let H be a finite simple hypergraph and J(H) the cover ideal of H. We define the shadows of hypergraph, H, described as a collection of smaller hypergraphs related to H under some conditions. We then investigate how the shadows of H preserve information about the associated primes of the powers of J(H). Finally, we apply our findings on shadows to study the persistence property of square-free monomial ideals and construct some examples exhibiting failure of contai…

HypergraphMonomialProperty (philosophy)Associated primes Cover ideals Hypergraphs Powers of idealsMathematics::Number Theory0102 computer and information sciencesHypergraphsCommutative Algebra (math.AC)01 natural sciencesCover idealsCombinatoricsSimple (abstract algebra)FOS: MathematicsMathematics - CombinatoricsDiscrete Mathematics and CombinatoricsPowers of ideals0101 mathematicsMathematicsAlgebra and Number TheoryIdeal (set theory)Mathematics::Commutative Algebra010102 general mathematicsAssociated primes; Cover ideals; Hypergraphs; Powers of idealsMonomial idealSquare-free integerMathematics - Commutative AlgebraSettore MAT/02 - AlgebraCover (topology)010201 computation theory & mathematicsAssociated primesSettore MAT/03 - GeometriaCombinatorics (math.CO)05C65 13F55 05E99 13C99
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Continuous 3-year outdoor operation of a flat-panel membrane photobioreactor to treat effluent from an anaerobic membrane bioreactor

2020

[EN] A membrane photobioreactor (MPBR) plant was operated continuously for 3 years to evaluate the separate effects of different factors, including: biomass and hydraulic retention times (BRT, HRT), light path (Lp), nitrification rate (NOxR), nutrient loading rates (NLR, PLR) and others. The overall effect of all these parameters which influence MPBR performance had not previously been assessed. The multivariate projection approach chosen for this study provided a good description of the collected data and facilitated their visualisation and interpretation. Forty variables used to control and assess MPBR performance were evaluated during three years of continuous outdoor operation by means …

INGENIERIA HIDRAULICAEnvironmental Engineering0208 environmental biotechnologyPhotobioreactorBiomasschemistry.chemical_elementNitrifying bacteria02 engineering and technologyMicroorganismesPLS010501 environmental sciencesWastewaterMembrane photobioreactor01 natural sciencesPhotobioreactorsPartial least squares regressionMicroalgaeAnaerobiosisBiomassWaste Management and DisposalEffluentTECNOLOGIA DEL MEDIO AMBIENTE0105 earth and related environmental sciencesWater Science and TechnologyCivil and Structural EngineeringPCAbiologyOutdoor06.- Garantizar la disponibilidad y la gestión sostenible del agua y el saneamiento para todosEcological ModelingPhosphorusMembranes ArtificialBacteris nitrificantsbiology.organism_classificationPulp and paper industryPollution020801 environmental engineeringchemistryNitrifying bacteriaPrincipal component analysisEnvironmental scienceNitrificationEnginyeria ambiental
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A Split-Window Algorithm for Estimating LST From Meteosat 9 Data: Test and Comparison With Data and MODIS LSTs

2009

The main purpose of this letter is to give an operational algorithm for retrieving the land surface temperature (LST) using the Spinning Enhanced Visible and Infrared Imager data onboard the Meteosat Second Generation (MSG2) satellite. The algorithm is a split-window method using the two thermal infrared channels IR10.8 and IR12.0. The MODTRAN 4.0 code was used to obtain numerical coefficients of the algorithm proposed. The results show that for viewing angles lower than 50deg the algorithm is capable of producing LST with a standard deviation of 0.7 K and a root-mean-square error (rmse) of 1.3 K. The algorithm has been applied to a series of MSG2 images obtained from an MSG antenna system …

In situMeteorologyLand surface temperatureMean squared errorMODTRANGeotechnical Engineering and Engineering GeologyStandard deviationEnvironmental scienceSatelliteElectrical and Electronic EngineeringSplit windowImage retrievalAlgorithmRemote sensingIEEE Geoscience and Remote Sensing Letters
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Molte Palermo. Temi

2019

Nel tema delle incompiute idee di città possibili si riconoscerà il paradigma connotativo dello stesso divenire di Palermo, lungo un percorso millenario di processi di trasformazione nessuno dei quali portato a compimento, in virtù di quel valore distintivo di exemplum che non necessita di ulteriori e conclusive dimostrazioni. Il corso della storia, del resto, ha imposto a Palermo il ciclico riproporsi di destini interrotti. Tale si rilevò l’invenzione della città capitale, quella della “quadratura geometrica e della croce di strade” sovrimpressa a quella archetipica e fondativa della Pan-ormos scambiatrice. E l’incompiutezza sarà il tratto distintivo della città dei rettifili stradali otto…

In the theme of unfinished ideas of possible cities will recognize the connotative paradigm of the evolution of Palermo will be recognised along a thousand year path of transformational processes none of which was completed by virtue of the distinctive value of exemplum that does not require additional and conclusive demonstrations. The course of history has moreover imposed on Palermo a cyclical recurrence of broken destinies. This was evidence of the invention of the capital city that of the “geometric square and the cross roads” superimposed on the archetypal underpinning of Pan-ormos as a place of exchange. And incompleteness will be the hallmark of the city of the nineteenth century straight roads heading towards undefined destinations the symptomatic expression of the idea of a preordained effect of suspension. Similarly unfinished will be the Palermo of the redevelopment plans in the nineteenth and twentieth centuries upto the shapeless development of the contemporary city and the new arterial routes (the Circonvallazione) manifestations of further “Palermo as abstraction” ever more distant from “Palermo as places”. A city ultimately characterized by continuous metamorphoses replacement of values absorptions oblivion and cultural desecration. From this distance one can indeed observe Palermo from a marginal and peripherical point of view as regards its urban limits opening up a different prospect penetrating and maybe even superior able to understand facts and phenomena in depth.Settore ICAR/14 - Composizione Architettonica E Urbana
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"Table 26" of "Measurement of $J/\psi$ at forward and backward rapidity in $p+p$, $p+A$l, $p+A$u, and $^3$He$+$Au collisions at $\sqrt{s_{_{NN}}}=200…

2020

J/psi mean pT squared in 3He+Au collisions as a function of N_coll. The statistical and systematic uncertainties vary point-to-point and are listed for each measured value. An additional global systematic uncertainty is provided in each column heading, which applies to all data points per column.

InclusivepT squaredJ/psi --> mu+mu-200.0
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"Table 25" of "Measurement of $J/\psi$ at forward and backward rapidity in $p+p$, $p+A$l, $p+A$u, and $^3$He$+$Au collisions at $\sqrt{s_{_{NN}}}=200…

2020

J/psi mean pT squared in p+Au collisions as a function of N_coll. The statistical and systematic uncertainties vary point-to-point and are listed for each measured value. An additional global systematic uncertainty is provided in each column heading, which applies to all data points per column.

InclusivepT squaredJ/psi --> mu+mu-200.0
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"Table 24" of "Measurement of $J/\psi$ at forward and backward rapidity in $p+p$, $p+A$l, $p+A$u, and $^3$He$+$Au collisions at $\sqrt{s_{_{NN}}}=200…

2020

J/psi mean pT squared in p+Al collisions as a function of N_coll. The statistical and systematic uncertainties vary point-to-point and are listed for each measured value. An additional global systematic uncertainty is provided in each column heading, which applies to all data points per column.

InclusivepT squaredJ/psi --> mu+mu-200.0
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