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Artificial intelligence and remote sensing for spatial prediction of daily air temperature:case study of Souss watershed of Morocco

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Geo-Spatial Information Science 2022年第2期25卷 244-258页

作者： Modeste Meliho Abdellatif Khattabi Driss Zejli Collins Ashianga Orlando Caleb E.Dansou Ecole Nationale des sciences Appliquées Kénitra-Laboratoire Ingénierie des Systèmes Avancés(ISA) UniversitéIbn TofailKenitraMorocco Ecole Nationale Forestière d’Ingénieurs SaléMorocco Ecole Nationale des sciences Appliquées Kénitra-Laboratoire Ingénierie des Systèmes Avancés(ISA) SaléMorocco sciences de données École des sciences de l’information(ESI)RabatMorocco

Air temperature(Tair)is a fundamental variable in climate research and climate impact *** field observations do not accurately capture its spatial distribution due to the sparse and uneven distribution of weather stations,especially in remote areas where the local variability is *** circumvent this problem,in this study,remote sensing and weather station data were used to estimate Tair in the Souss watershed in *** statistical methods,including linear regression and partial least squares(PLS),and four machine learning algorithms,namely k-nearest neighbors,random forest(RF),extreme gradient boost,and Cubist,were used for modeling and predicting Tair and its performance were evaluated using random subsets and *** resolution imaging spectroradiometer predictors,including Terra band 32 emissivity,Terra nighttime land surface temperature,Terra local time of night observation,Aqua band 31 emissivity,Aqua daytime land surface tempera-ture,and Aqua nighttime land surface temperature(ALSTN),and auxiliary inputs,including sky-view,elevation,slope,and hillshade,were used as inputs for *** results showed that the Cubist and RF were the most accurate models(RMSE=2.09°C and 2.13°C,R2=0.91 and 0.90,respectively),while PLS had the lowest predictive power(RMSE=2.71°C;R2=0.83).The overall performance of the models for estimating Tair in the study area was generally satisfac-tory,with RMSE limited to less than 3°C for all ***,the station data reliability was still an issue,with only four of the seven stations marked by complete meteorological data.

关键词： Air temperature remote sensing machine learning Morocco

Energy calibration of laterally segmented electromagnetic calorimeters based on neutral pion detection

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Nuclear Science and Techniques 2017年第11期28卷 164-171页

作者： Malek Mazouz Faculté des sciences de Monastir 5000 Monastir Tunisia

This paper describes a method for energy calibration of laterally segmented electromagnetic calorimeters based on the detection of two-photon decays of π~0 *** calibration procedure performs a X^2 function minimization between the measured π~0 energy in the calorimeter and its expected energy deduced from the π~0 momentum direction. The performance of this technique is demonstrated with a Monte Carlo simulation of an experimental case where biased calibration coefficients are employed. The real calibration coefficients are restored with less than 1% relative accuracy when a sufficient number of π~0 is detected. This technique is applied to monitor daily the calibration coefficients of the calorimeter used in the Jefferson Lab Hall A DVCS experiments.

关键词： Electromagnetic calorimeters Energy calibration Detector modeling and simulations Data processing methods

Thermoluminescent response of gamma irradiated Na^(+)–Cu^(+) ionexchanged silicate glass in large dose range

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Nuclear Science and Techniques 2023年第5期34卷 22-32页

作者： Safa Toumi Khaled Farah Laboratoire de Physico‑Chimie des Matériaux Département de PhysiqueFacultédes Sciences de MonastirUniversitéde MonastirMonastirTunisia institut Supérieur du Transport et de la Logistique de Sousse Universitéde Sousse4023 SousseTunisia Laboratoire de Recherche en Energie et Matière Développement des Sciences Nucléaires(LR16CNSTN02)Centre National des Sciences et Technologies Nucléaires2020 Sidi‑ThabetTunisia

The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous *** ion-exchange process is primarily used to introduce copper ions into glass *** thermoluminescence(TL)of silicate glass was studied to evaluate its potential as gamma-sensitive material for dosimetric applications;the effect of copper doping on the thermoluminescent sensitivity was investigated using the Cu-Na ion-exchange technique for different concentrations and doping conditions,over a wide dose range of 10 mGy to 100 *** results showed that Cu doping significantly improved the sensitivity of the glasses to gamma *** the ion-exchange,two peaks appeared in the glow curves at approximately 175 and 230°C,respectively,which possibly originated from the Cu^(+) centers,along with a weak TL peak at around 320℃.We also attempted to explain the origin of the observed thermoluminescence by exploiting the Electron paramagnetic resonance(EPR)*** results clearly show quenching of the TL emission with increasing copper *** present work indicates that the thermoluminescence response of these glasses to gamma rays can be reasonably measured in the range of 0.001-100 *** study also facilitates the understanding of the basic TL mechanism in this glass system.

关键词： Cu-Na ion-exchange Silicate glass Thermoluminescence Gamma irradiation Electron paramagnetic resonance

ON CONSERVATIVE APPROXIMATION BY LINEAR POLYNOMIAL OPERATORS AN EXTENSION OF THE BERNSTEIN'S OPERATOR

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Analysis in Theory and Applications 1995年第1期11卷 62-71页

作者： Francisco-Javier Munoz-Delgado Victoriano Ramirez-Gonzalez Paul Sablonniere Universidad de Jaen SpainUniversidad de Granada SpainInstitut National des Sciences Appliquees France

In this work we slwly linear polynomial operators preserving some consecutive i-convexities and leaving in-verant the polynomtals up to a certain degree. First we study the existence of an incompatibility between the conservation of cenain i-cotivexities and the invariance of a space of polynomials. Interpolation properties are obtained and a theorem by Berens and DcVore about the Bernstein's operator ts extended. Finally, from these results a genera'ized Bernstein's operator is obtained.

关键词： LPO ON CONSERVATIVE APPROXIMATION BY LINEAR POLYNOMIAL OPERATORS AN EXTENSION OF THE BERNSTEIN’S OPERATOR

Photochemical production of dissolved inorganic carbon from suwannee river humic acid

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Chinese Journal of Oceanology and Limnology 2009年第3期27卷 570-573页

作者：汪学军楼涛谢惠祥 College of Chemistry Chemical Engineering & Environmental ScienceQingdao University institut des sciences de la mer de Rimouski Université du Québec à Rimouski

The photochemical mineralization of dissolved organic carbon(DOC) to dissolved inorganic carbon(DIC) is a key process in carbon *** a Suntest CPS solar simulator,Suwannee River humic acid(SRHA) was photooxidated to examine the effects of O2 levels,the wavelength of incident light,and the concentration of Fe on the photoproduction of *** the O2 abundance enhanced photodegradation of *** rate of DIC photoproduction under air saturation in the first 24 h(4.40 μmol/(L h)) was increased by a factor of 1.56 under O2 saturation,but fell by only 36% under N2 *** evaluate the relative importance of UV-B,UV-A,and visible radiation in the photodegradation,we examined the above process using Mylar-d films and UF-3 and UF-4 plexiglass *** results indicated that the UV-B,UV-A and visible wavelengths accounted for 31.8%,32.6% and 25.6%,respectively,of DIC production with simulated sunlight *** above results also indicated that photoproduction of DIC could take place in natural water at depths greater than those that UV light can *** 20 μmol/L desferrioxamine mesylate(DFOM,a strong Fe complexing ligand) was added,the rate of DIC photoproduction fell to 55.6% that of the original SRHA samples with 5.46 μmol/L Fe.

关键词： dissolved inorganic carbon dissolved organic carbon humic acid photochemistry

X chromosome inactivation and active X upregulation in therian mammals: facts, questions, and hypotheses

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Journal of Molecular Cell Biology 2015年第1期7卷 2-11页

作者： Reiner A.Veitia Frederic Veyrunes Samuel Bottani James A.Birchler institut Jacques Monod ParisFrance Universite Paris Diderot ParisFrance institut des sciences de l’Evolution de Montpellier CNRS/Universite Montpellier IIMontpellierFrance Matiere et Systemes Complexes ParisFrance Division of Biological sciences University of MissouriColumbiaMOUSA

X chromosome inactivation is a mechanism that modulates the expression of X-linked genes in eutherian females(XX).Ohno proposed that to achieve a proper balance between X-linked and autosomal genes,those on the active X should also undergo a 2-fold *** some support for Ohno's hypothesis has been provided through the years,recent genomic studies testing this hypoth-esis have brought contradictory results and fueled *** far,there are as many results in favor as against Ohno's hypothesis,depending on the nature of the datasets and the various assumptions and thresholds involved in the ***,they have con-firmed the importance of dosage balance between X-linked and autosomal genes involved in stoichiometric *** facts as well as questions and hypotheses are discussed below.

关键词： X inactivation X chromosome upregulation monoallelic expression imprinting dosage balance

Do endemic species always have a low competitive ability? A test for two Mediterranean plant species under controlled conditions

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Journal of Plant Ecology 2012年第3期5卷 305-312页

作者： Eric Imbert Sami Youssef David Carbonell Alex Baumel institut des sciences de l’Evolution CNRS 5554Universite Montpellier 2France institut Mediterraneen d’Ecologie et de Paleoecologie UMR CNRS/IRD 6116Universite Aix MarseilleFrance

Aims Many observations concerning biological and ecological differentiation between narrow endemic and widespread congeneric plant species suggest that narrow endemic species are constrained to colonize marginal habitats because of a low tolerance to *** this topic being an important issue both for understanding evolutionary processes leading to endemism and for conservation purposes,few studies have been performed to compare competitive abilities between endemic and widespread ***,we present two independent experiments performed under controlled conditions using two different pairs of endemic and widespread congeneric species:Centaurea corymbosa/Centaurea maculosa and Arenaria provincialis/Arenaria serpyllifolia,both endemic species occurring in rocky calcareous *** Mature seeds of *** and *** were sown in pots containing ramets of the common grass,Brachypodium *** were sorted in three treatments according to grass cover(low,intermediate and high).A control treatment(without competition)was also ***,seedling survival and rosette growth were *** the comparisons between *** and ***,seeds from natural populations were first sown without a *** week after germination,healthy seedlings were transplanted in pots without Brachypodium seedling(control)or containing two Brachypodium seedlings(low competition)or four seedlings(high competition).We checked the number of capsules per individual,and we harvested the biomass after capsule *** Findings despite differences in the protocol design,results are congruent,and in both cases,endemic species are highly affected by the presence of a competitor,as are the widespread species,although we did not detect any differences between species for response to *** results are discussed in relation to processes leading to endemism,suggesting that the specialist model is more likely for both the

关键词： endemism conservation biology Mediterranean area competitive response

Laser Polarization Orientations in(e,2e)Reactions in Atoms

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Chinese Physics Letters 2015年第8期32卷 62-65页

作者： Ajana I. Makhoute A. Khalil D. UFR de Physique du Rayonnement et des Interactions Laser-Matière Faculté des SciencesUniversité Moulay Ismail

Second-order Born calculations are performed to investigate the triple differential cross sections of coplanar asymmetric laser-assisted （e, 2e） collisions for hydrogen and helium targets. The incident electron is considered to be dressed by the laser field in a nonperturbative manner by choosing the Volkov solutions in both the initial and final channels. Detailed calculations of the scattering amplitudes are performed using the Sturmian basis expansion. The state of the ejected electron is described by a Coulomb-Volkov wave function. Two geometries are investigated in which the laser polarization vector is either parallel to the incident momentum of the projectile or parallel to the momentum transfer. Our numerical results show that, in the low energy range, these two laser polarization orientations give the same shape and the same order of magnitude of laser-assisted ionization cross sections of helium and hydrogen targets.

关键词： Laser Polarization Orientations in e,2e)Reactions in Atoms

Surface Effects on Wannier Excitons in Superlattices:Monte Carlo Simulation

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Chinese Physics Letters 2002年第8期19卷 1164-1167页

作者： K. Afif, A. Benyoussef and J. Diouri Laboratoire de Magnetisme Faculte des Sciences Groupe d"Electronique et de Physique du Solide Faculte des Science

Using a Monte Carlo quadrature, we calculate by a variational method the binding energy Eb of Wannier excitons in N-period m-CdMnTe/n-CdTe superlattices, including or not including the step discontinuity in the potential barrier at the interface, and with varying N as well as well width. The calculation is performed in the framework of the effective mass approximation for both heavy-hole and light-hole excitons. The degree of exciton localization dependence on these parameters is accurately illustrated.

关键词： Monte Carlo methods