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An Automatic Optimization Technique for the Calibration of a Physically Based Hydrological Rainfall-Runoff Model

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Journal of Geoscience and Environment Protection 2021年第3期9卷 1-20页

作者： Zohou Pierre Jérôme Alamou Adéchina Eric Obada Ezéchiel Biao Iboukoun Eliézer Eugène C. Ezin Université d’Abomey-Calavi (UAC) Abomey-Calavi Bénin laboratoire de Recherche en sciences Informatiques et applications (LRSIA) UAC Abomey-Calavi Bénin laboratoire d’Hydrologie Appliquée (LHA) UAC Abomey-Calavi Bénin Université Nationale des sciences Technologies Ingénierie et Mathématiques (UNSTIM) Abomey Bénin

Models are tools widely used in the prediction of hydrological phenomena. The present study aims to contribute to the implementation of an automatic optimization strategy of parameters for the calibration of a hydrological model based on the least action principle (HyMoLAP). The Downhill Simplex method is also known as the Nelder-Mead algorithm, which is a heuristic research method, is used to optimize the cost function on a given domain. The performance of the model is evaluated by the Nash Stucliffe Efficiency Index (NSE), the Root Mean Square Error (RMSE), the coefficient of determination (R2), the Mean Absolute Error (MAE). A comparative estimation is conducted using the Nash-Sutcliffe Modeling Efficiency Index and the mean relative error to evaluate the performance of the optimization method. It appears that the variation in water balance parameter values is acceptable. The simulated optimization method appears to be the best in terms of lower variability of parameter values during successive tests. The quality of the parameter sets obtained is good enough to impact the performance of the objective functions in a minimum number of iterations. We have analyzed the algorithm from a technical point of view, and we have carried out an experimental comparison between specific factors such as the model structure and the parameter’s values. The results obtained confirm the quality of the model (NSE = 0.90 and 0.75 respectively in calibration and validation) and allow us to evaluate the efficiency of the Nelder-Mead algorithm in the automatic calibration of the HyMoLAP model. The developed hybrid automatic calibration approach is therefore one of the promising ways to reduce computational time in rainfall-runoff modeling.

关键词： Optimization HyMoLAP Automatic Calibration Validation Nelder-Mead Algorithm

Beamforming Scheme for MIMO Relay Based 5G and beyond Wireless Network

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Open Journal of Applied sciences 2021年第10期11卷 1157-1176页

作者： Ali Mahamoud Ali Bakhit Amine Adoum Idriss Saleh Bachar Mahamoud Youssouf Khayal laboratoire de mathématiques Modélisation Informatique Applications et Simulation LARTIC FSEA/école Doctorale Sciences Techniques et Environnement CNRD Université de N’Djamena N’Djamena Tchad Ecole Nationale Superieure des Technologies de l’Information et de la Communication (ENASTIC) N’Djamena Tchad

In this paper, in order to attain the maximum ergodic capacity and significantly increase the spectral efficiency of wireless communication systems, novel linear beamforming is proposed for dual-hop amplify-and-forward (AF) multi-relay networks. The linear beamforming is designed based on the maximization of the signal-to-interference-plus-noise ratio (SINR) and signal-to- leakage-and-noise ratio (SLNR). The channel state information (CSI) is used in applying this new design to multi-relay (MR) nodes between the source and relays as well as relays and destination. The beamforming optimization problem is solved by using the Fukunaga-Koontz Transform (FKT). The scheme can achieve intra-node array and distributed gains by using multiple antennas and multi-relays (MRs). The performance of the proposed scheme demonstrates that by considering interference mitigation criteria the ergodic capacity at a significant level is improved as compared to the conventional techniques. Therefore, the proposed techniques based on the maximization of the signal-to-interference-plus-noise ratio (SINR) and signal-to-leakage-and-noise ratio (SLNR) relay processing outperform other conventional techniques in case of a multi-relay dual-hop network in terms of ergodic.

关键词： Beamforming Ergodic Capacity MIMO Multi-Relay Network

PEONIES: Comparative Study by Anatomy and TLC of Three Traditional Chinese Medicinal Plants

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Chinese Medicine 2013年第4期4卷 166-172页

作者： F. El Babili M. El Babili I. Fouraste C. Chatelain Faculté des sciences Pharmaceutiques Laboratoire de BOTANIQUE Toulouse France Faculté des sciences Pharmaceutiques Laboratoire de Pharmacognosie Toulouse France Université Claude Bernard Lyon I Institut Michel Pacha La Seyne sur Mer France

Anatomical and TLC study of three Chinese peonies were conducted to make a comparative analysis. Peonies (Paeonia suffruticosa (tree peony), Paeonia lactiflora (Chinese peony) and Paeonia veitchii (Chinese peony)) are traditionally used on the Qinghai-Tibet Plateau in China. Recent studies have shown that the peonies have different pharmacological activities and clinical applications. To distinguish these three species of peonies and ensure the safety and effectiveness in their use, the microscopic characteristics and chromatographic profile of their roots and the corresponding powder were studied. Plant materials sectioned and stained and the raw powder were studied with an optical microscope using standard techniques in microscopy. The results of microscopic features and TLC were described and illustrated. The three species have different microscopic characteristics and TLC profiles, which allow us to distinguish them. In fact, with the help of features semi-quantitative and qualitative, an identification key was developed in our work and illustrated with photos and a table. The aim of our work was to show that the optical microscopy and related techniques provide a achievable practicality, which can be applied without ambiguity to the authentication of species peonies.

关键词： Peonies Microscopic Identification TLC P. suffructicosa P. lactiflora P. vetchii

Third-order nonlinear optical susceptibility of crystalline oxide yttria-stabilized zirconia

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Photonics Research 2020年第2期8卷 110-120页

作者： GUILLAUME MARCAUD SAMUEL SERNA KARAMANIS PANAGHIOTIS CARLOS ALONSO-RAMOS XAVIER LE ROUX matHIAS BERCIANO THOMAS MAROUTIAN GUILLAUME AGNUS PASCAL AUBERT ARNAUD JOLLIVet ALICIA RUIZ-CARIDAD LUDOVIC LARGEAU NATHALIE ISAC ERIC CASSAN SYLVIA matZEN NICOLAS DUBREUIL MICHEL RERAT PHILIPPE LECOEUR LAURENT VIVIEN Centre de Nanosciences et Nanotechnologies(C2N) Université-Paris-SudCNRS UMR 9001Universite Paris-SaclayOrsay 91405France Department of materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMasschusetts 02139USA Department of Physics Bridgewater State UniversityBridgewaterMassachusetts 02325USA Institut des sciences Analytiques et de Physico-Chimie pour l’Environnement et les matériaux CNRSUniversite de Pau et des Pays de l’Adour64053 Pau CedexFrance laboratoire Charles Fabry Institut d’Optique Graduate SchoolCNRSUniversitéParis-Saclay91127 Palaiseau CedexFrance LP2N Institut d’Optique Graduate SchoolCNRSUniv.Bordeaux33400 TalenceFrance

Nonlinear all-optical technology is an ultimate route for the next-generation ultrafast signal processing of optical communication *** nonlinear functionalities need to be implemented in photonics,and complex oxides are considered as promising candidates due to their wide panel of *** this context,yttria-stabilized zirconia(YSZ)stands out,thanks to its ability to be epitaxially grown on silicon,adapting the lattice for the crystalline oxide family of *** report,for the first time to the best of our knowledge,a detailed theoretical and experimental study about the third-order nonlinear susceptibility in crystalline *** self-phase modulation-induced broadening and considering the in-plane orientation of YSZ,we experimentally obtained an effective Kerr coefficient of n2YSZ=4.0±2×10^-19 m^2·W^-1 in an 8%(mole fraction)YSZ *** agreement with the theoretically predicted n2YSZ=1.3×10^-19 m^2·W^-1,the third-order nonlinear coefficient of YSZ is comparable with the one of silicon nitride,which is already being used in nonlinear *** promising results are a new step toward the implementation of functional oxides for nonlinear optical applications.

关键词： materials. nonlinear crystalline

Polycaprolactone (PCL) Chains Grafting on the Surface of Cellulose Nanocrystals (CNCs) during <i>In Situ</i>Polymerization of <i>ε</i>-Caprolactone at Room Temperature

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materials sciences and applications 2020年第11期11卷 744-756页

作者： Jérémy Astruc Patrice Cousin Gaétan Laroche mathieu Robert Saïd Elkoun Center of Innovative Technology and Eco-design (CITE) University of Sherbrooke Granby QC Canada laboratoire d’Ingénierie de Surface Département de Génie des Mines de la Métallurgie et des Matériaux Centre de recherche sur les Matériaux avancés Pavillon Adrien-Pouliot University of Laval Québec QC Canada Centre de Recherche du CHU de Québec Hopital Saint-Francois d’Assise Québec QC Canada

This work aimed at investigating the feasibility of surface modification of cellulose nanocrystals (CNCs) using in situ ring opening polymerization of ε-caprolactone (ε-CL) at room temperature. Residues of flax and milkweed (Asclepias syriaca) stem fibers were used as a source of cellulose to obtain and isolate CNCs. The cationic ring opening polymerization (CROP) of the monomer ε-CL was used to covalently graft polycaprolactone (PCL) chains at the CNCs surface. Silver hexafluoroantimonate (AgSbF6) was used in combination with the extracted CNCs to initiate, at room temperature, the polymerization and the grafting reactions with no other stimulus. Fourier-Transform InfraRed (FTIR), X-ray Photoelectron Spectrometry (XPS), UV/visible absorption and Gel Permeation Chromatography (GPC) analyses evidenced the presence of PCL chains covalently grafted at CNCs surface, the formation of Ag(0) particles as well as low or moderate molecular weight free PCL chains.

关键词： Cellulose Nanocrystals (CNCs) Simultaneous Polymerization and Surface Grafting ε-Caprolactone Cationic Ring Opening Polymerization Room Temperature Silver Hexafluoroantimonate

On the Validity of the Effective Index Method for Long Period Grating Photonic Crystal Fibers

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materials sciences and applications 2012年第5期3卷 310-316页

作者： Dhia Khadri Walid Belhadj Douha Gamra Fathi AbdelMalek Habib Bouchriha Department of Physics Jazan University Jazan Kingdom of Saudi Arabia Ecole Polytechnique de Montreal Genie Physique Montreal Canada Faculté des sciences de Bizerte Bizerte Tunisia laboratoire de Physique Quantique et Photonique Faculte des Sciences de Tunis Tunis Tunisia

This paper focuses on the investigation of modal characteristics and sensing properties of long period grating photonic crystal fibers (LPG-PCFs). An improved effective index method is employed with an objective to study its limitations for various designs of LPG-PCFs. Results so obtained with the above method are compared with the corresponding values of multiple multipole (MMP) method results which points the range of validity and applicability of the improved effective index method to LPG-PCFs. It is shown that this method is excellent when the surrounding media is assumed to be air. However, it becomes less accurate when the fiber is immersed into a liquid with a refractive index close to that of the cladding.

关键词： Long Period Gratings Photonic Crystal Fiber (LPG-PCF) Improved Effective Index MMP Cladding Modes Sensor Sensitivity

Assessment of Intra-Seasonal Variability and Trends of Precipitations in a Climate Change Framework in West Africa

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Atmospheric and Climate sciences 2022年第1期12卷 150-171页

作者： Daniel Bio Tore Adechina Eric Alamou Ezéchiel Obada Eliezer Iboukoun Biao Esdras B. Josué Zandagba laboratoire de Géosciences de l’Environnement et applications Université Nationale des Sciences Technologies Ingénierie et Mathématiques (UNSTIM) Abomey Benin laboratoire d’Hydrologie Appliquée (LHA) Institut National de l’Eau Université d’Abomey-Calavi (UAC) Godomey Benin école Nationale Supérieure des Travaux Publics (ENSTP/UNSTIM) Abomey Benin école Nationale Supérieure de Génie mathématique et Modélisation (ENSGMM/UNSTIM) Abomey Benin

Climate change has led human beings to take an interest in the study of meteorological and climatic phenomena. In fact, the main impact of climate change on different sectors of society is caused by extreme events since the occurrence of extreme events leads to more impact related to change in mean climate. Unfortunately, the West African region is vulnerable to extreme rainfall impact because its economy is based on rain-fed agriculture. This study examined the seasonal variability of extreme rainfall in West Africa. Eight (8) climate indices were chosen from among the 27 defined by the Expert Team on Climate Change Detection and Indices (etCCDI). The nonparametric Mann-Kendall test was used to assess the seasonal trends. The indices of the same types (frequency or intensity) were compared to assess the intra-seasonal variation of extreme precipitation. The results indicate that, regardless of the season, the Gulf of Guinea receives more rainfall than the Sahel. This phenomenon is due to the fact that the coastal part of West Africa is under the influence of evaporation which is observed at the Atlantic Ocean and during the monsoon, while the other part is dominated by the desert. Mann-Kendall’s test revealed upward and downward trends during each season. The increase in extreme rainfall trends in the number of consecutive dry days suggests that droughts, due to global warming, could be observed and could have severe consequences in terms of water availability, energy supply, agricultural yields and ecosystems in West Africa. In addition, it can lead to the loss of biodiversity and health issues. It is therefore essential for policymakers or decisions makers to determine strategies and mitigation measures against climate change and its impacts on populations.

关键词： Extreme Precipitation Indices Variability Trend Mann Kendall West Africa

design of a Multimodal Light Sheet Optical System for Multivariate applications in Phytopathology

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Optics and Photonics Journal 2021年第5期11卷 110-120页

作者： Mama Sangare mathieu Hebert Anthony Cazier Pierre Chavel Institut des sciences Appliquées Université des Sciences Techniques et Technologies de Bamako (USTTB) Bamako Mali laboratoire Hubert Curien Institut d’Optique Graduate School Université Jean Monnet de Saint-Etienne Université de Lyon CNRS Saint-Etienne France

The design of optical instruments is an active subject due to improvement in lens techniques, fabrication technology, and data handling capacity. Much remains to do to expand its application to phytopathology, which would be in particular quite useful to improve crop growth monitoring in countries like Mali. An optical multimodal system for plant samples has been developed to improve the characterization of leaf disease symptoms, provide information on their effects, and avoid their spread. Potentially inexpensive components (laser, lens, turntables camera and sample, filter, lens, camera and computer) have been selected, assembled and aligned on an optical table into a multimodal system operating in transmission, reflection, diffusion and fluorescence. The illumination and observation angles can be adjusted to optimize viewing conditions in the four modes. This scientific contribution has been an initiation into the design and implementation of an optical instrument. Initial results are shown and will now be extended in cooperation with agronomic laboratories in African countries for tests on specific plant diseases in relation with prevailing climate conditions.

关键词： design Optical System Light Sheet Multimodal Multivariate Phytopathology

Large electrical strain in lead-free K_(0.5)Na_(0.5)NbO_(3)-based ceramics by heterovalent doping

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Journal of materiomics 2023年第5期9卷 959-970页

作者： Xiangjian Wang Jun Wang Wenping Geng Guohua Dong Brahim Dkhil Xiaojie Lou Department of Information Engineering Quzhou College of TechnologyQuzhou324000China Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behavior of MaterialsXi'an Jiaotong UniversityXi'an710049China Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan030051China Electronic materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchXi'an Jiaotong UniversityXi'an710049China Applied Physics Division of Materials ScienceDepartment of Engineering Sciences and MathematicsLuleåUniversity of TechnologySE-97187LuleåSweden laboratoire Structures Proprietes et Modelisation des SolidesUniversite Paris SaclayCentraleSupelecCNRS-UMR8580Grande Voie des VignesCh^atenay MalabryCedex92295France

Heterovalent doped(K_(0.48-0.07)xNa_(0.52-0.43)xBi_(0.5)x)(Nb_(0.95-0.95x)Sb_(0.05-0.05x)Zrx)O_(3)ceramics were fabricated using conventional solid-state ***,the phase structures,dielectric,ferroelectric,and electricstrain properties were *** compositions were tuned to be located at polymorphic phase boundary with increasing heterovalent Bi3t and Zr4t doping levels.A large strain of 0.19%was obtained at relatively low electric fields of 30 kV/cm in the composition of x=*** normalized large-signal d33*values were approximately 633 pm/V under a low driving electric field of 30 kV/cm,which were comparable or larger than the values reported for other lead-free *** large strains obtained can be attributed to the formation of nanodomains and high-density domain walls,which were confirmed by the observations of domain morphology using transmission electron microscopy(TEM)*** temperature stability of the strain properties of the x=0.04 sample could be ascribed to the sluggish behaviour for the local structural heterogeneity in heterovalent-ion doped KNN *** simulations revealed that the Zr^(4t)produce the local stress at the BO6 octahedra and Bi3t could yield off-centering of AO12 ployhedron due to the nature of Bi 6s lone pair electrons,which induced lattice expansion and local distortions in the *** local displacements are strongly anisotropic in heterovalent-ion doped *** is believed that random local fields exist in these compositions owing to the eixstence of charge *** heterovalent doping of Bi^(3t)and Zr^(4t)could destory simultaneously the orthorhombic symmetry and the short-range ferroelecctric order,leading to the formation of complex nanodomains and local structral *** doping may,therefore,offer a new avenve to design novel K0.5Na0.5NbO3(KNN)-based materials for their mutifunctional applications.

关键词： Lead-free Strain Heterovalent doping Local structure Nanodomain