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Analytical and numerical modeling of resonant piezoelectric devices in China-A review

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Science China(Physics,Mechanics & Astronomy) 2008年第12期51卷 1775-1807页

作者： YANG JiaShi1,2↑ & YANG ZengTao1 1 Institute of Mechanics and Sensing Technology, School of Civil Engineering and Architecture, Central South University, Changsha 410083, China 2 Department of Engineering Mechanics, University of nebraska, Lincoln, ne 68588-0526, USA 1. Institute of Mechanics and Sensing Technology School of Civil Engineering and Architecture Central South University Changsha 410083 China 2. Department of Engineering Mechanics University of Nebraska Lincoln NE 68588-0526 USA

The results on theoretical and numerical modeling of resonant piezoelectric devices in China are reviewed. Solutions to dynamic problems of the propagation of bulk acoustic waves (BAW), surface acoustic waves (SAW), vibrations of finite bodies, and analyses of specific devices are discussed. results from both the ultrasonics community and mechanics researchers are included. It is hoped that the paper will be useful for the understanding, communication and collaboration between Chinese and foreign scholars. The paper may also be helpful for bridging the gap between ultrasonics and mechanics researchers on piezoelectricity re- search. The paper contains 316 references.

关键词： piezoelectricity wave vibration transducer resonator

Antidiarrhoeal activity of leaf methanolic extract of rauwolfia serpentina

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Asian Pacific Journal of Tropical Biomedicine 2012年第6期2卷 430-432页

作者： Ezeigbo II Ezeja MI Madubuike KG Ifenkwe DC Ukweni IA Udeh ne Akomas SC Department of Veterinary Physiology Biochemistry and Pharmacology College of Veterinary Medicine Michael Okpara University of Agriculture

Objective:To evaluate the antidiarrhoeal property of methanol extract of the leaves of rauwolfia serpentina(r. serpentina) in experimental diarrhoea induced by castor oil in ***:Doses of 100, 200 and 400 mg/kgr. serpentinaleaf methanol extracts were administered to castor oil induced diarrhoea mice to determine its antidiarrhoeal ***:All doses of the extract and the reference drug atropine sulphate(3 mg/kg, i.p.) produced a dose-dependent reduction in intestinal weight and fluid volume. The extracts also significantly reduced the intestinal transit in charcoal meal test when compared to diphenoxylate Hcl(5 mg/kg, p.o.).Conclusions:The results show that the extract of r. serpentin a leaves has a significant antidiarrhoeal activity and supports its traditional uses in herbal medicine.

关键词： rauwolfia serpentina Castor oil Antidiarrhoeal activity Intestinal transit

Influence of Prandtl Number on Thin Film Condensation in Forced Convection in an Inclined Wall Covered with a Porous Material

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Advances in Materials Physics and Chemistry 2022年第6期12卷 125-140页

作者： Goumbo Ndiaye Momath Ndiaye Vincent Sambou Pape Tamsir Ndiaye Madialène Sène Cheikh Mbow The Water Energy Environment and Industrial Processes Laboratory of the Polytech Higher School Cheikh Anta Diop University Dakar Senegal Laboratory of Fluids Mechanics and Transfers Faculty of Sciences and Technologies Cheikh Anta Diop University Dakar Senegal Department of the Ufr Hydraulics Rural Engineering Machinery and Renewable Energy University of Sine Saloum Elhadji Ibrahima NIASS Kaolack Senegal

The numerical study of thin film type condensation in forced convection of a saturated pure vapor in an inclined wall covered with a porous material is presented. The generalized Darcy-Brinkman-Forchheimer (DBF) model is used to describe the flow in the porous medium while the classical boundary layer equations have been exploited in the case of a pure liquid. The dimensionless equations are solved by an implicit finite difference method and the iterative Gauss-Seidel method. The objective of this study is to examine the influence of the Prandtl number on the hydrodynamic and thermal fields but also on the local Nusselt number and on the boundary layer thickness. For Pr ≤ 0.7 (low) the velocity and the longitudinal temperature increase with the Prandtl number. On the other hand, when Pr ≥ 2 (high) the Prandtl number no longer influences the velocity and the longitudinal temperature. The local Nusselt number increases as the Prandtl number increases and the thickness of the hydrodynamic boundary layer increases as the Prandtl number decreases.

关键词： Condensation Thin Film Forced Convection Inclined Porous Wall Generalized Darcy-Brinkman-Forchheimer Model Prandtl Number

LiDAr Is Effective in Characterizing Vine Growth and Detecting Associated Genetic Loci

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Plant Phenomics 2023年第4期5卷 836-851页

作者： Elsa Chedid Komlan Avia Vincent Dumas Lionel Ley Nicolas reibel Gisèle Butterlin Maxime Soma raul Lopez-Lozano Frédéric Baret Didier Merdinoglu Éric Duchêne INrAE University of StrasbourgUMR SVQV28rue de Herrlisheim68000 ColmarFrance INrAE UEAV28rue de Herrlisheim68000 ColmarFrance INrAE Aix-Marseille UniversitéUMR RECOVER3275 Route de Cézanne13182 Aix-en-ProvenceFrance INrAE Avignon UniversitéUMR EMMAHUMT CAPTE228route de l'aérodrome84914 AvignonFrance

The strong societal demand to reduce pesticide use and adaptation to climate change challenges the capacities of phenotyping new varieties in the ***-throughput phenotyping is a way to obtain meaningful and reliable information on hundreds of genotypes in a limited *** evaluated traits related to growth in 209 genotypes from an interspecific grapevine biparental cross,between IJ119,a local genitor,and Divona,both in summer and in winter,using several methods:fresh pruning wood weight,exposed leaf area calculated from digital images,leaf chlorophyll concentration,and LiDAr-derived apparent *** high-density genetic information obtained by the genotyping by sequencing technology(GBS),we detected 6 regions of the grapevine genome[quantitative trait loci(QTL)]associated with the variations of the traits in the *** detection of statistically significant QTLs,as well as correlations(r^(2))with traditional methods above 0.46,shows that LiDAr technology is effective in characterizing the growth features of the *** calculated with LiDAr-derived total canopy and pruning wood volumes were high,above 0.66,and stable between growing *** variables provided genetic models explaining up to 47%of the phenotypic variance,which were better than models obtained with the exposed leaf area estimated from images and the destructive pruning weight *** results highlight the relevance of LiDAr-derived traits for characterizing genetically induced differences in grapevine growth and open new perspectives for high-throughput phenotyping of grapevines in the vineyard.

关键词： LiDAr traits hundreds

Boundary Exact Controllability of the Heat Equation in 1D by Strategic Actuators and a Linear Surjective Compact Operator

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Applied Mathematics 2020年第10期11卷 991-999页

作者： Cheikh Seck Libasse Ane Abdoulaye Sène Département de Mathématiques de la FASTEF ex ENS de l’Université Cheikh Anta Diop de Dakar Sénégal Laboratoire d’Analyse Numérique et d’Informatique (LANI) de l’UFr SAT de l’Université Gaston Berger de Saint-Louis Sénégal Département de mathématiques et d’Informatique de la Faculté des Sciences et Techniques de l’Université Cheikh Anta Diop de Dakar Sénégal

In this paper we show a boundary result of controllability by a new approach using a linear, continuous and surjective operator built from the solution of the heat system. And, subsequently, the border exact controllability of the 1D heat equation through a compactness criterion and the use of strategic zone actuators were established.

关键词： Control Controllability Estimations Strategic Actuator

A unified approach to analysis and design of networked and quantized control systems

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A unified approach to analysis and design of networked and q...

SPECT-computed tomography in rats with TNBS-induced colitis: A first step toward functional imaging

2009中国控制与决策会议

作者： Dragan nei Department of Electrical and Electronic Engineering The University of MelbourneParkville3010ictoriaAustralia

＜正＞Ⅰ.EXTENDED ABSTrACT Control of systems over channels with capacity constraints is currently attracting a lot of attention due to a range of emerging control applications,such as drive-by-wire vehicles and fly-by-wire *** such systems,the control loop is closed via a channel that can transfer a finite amount of data per unit of time which imposes communication constraints that can not be ignored in analysis and design.

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World Journal of Gastroenterology 2017年第2期23卷 216-223页

作者： rachel Marion-Letellier Pierre Bohn romain Modzelewski Pierre Vera Moutaz Aziz Charlène Guérin Guillaume Savoye Céline Savoye-Collet INSErM Unit UMr1073 Rouen University and Rouen University Hospital QUANTIF LITIS EA 4108 Rouen University and Rouen University Hospital Service d’Anatomo-pathologie Rouen University Hospital Gastroenterology department Rouen University Hospital radiology department Rouen University Hospital

AIMTo assess the feasibility of SPECT-computed tomography (CT) in rats with trinitrobenzene sulfonic acid (TNBS)-induced acute colitis and confront it with model inflammatory *** was induced in Sprague-Dawley rats by intrarectal injection of TNBS (n = 10) while controls received vehicle (n = 10). SPECT-CT with intravenous injection of 10 MBq of 67Ga-Citrate was performed at day 2. SPECT-CT criteria were colon wall thickness and maximal wall signal intensity. Laboratory parameters were assessed: colon weight:length ratio, colon cyclooxygenase-2 expression by western blot and histological inflammatory *** weight/length ratio, colon COX-2 expression and histological inflammatory score were significantly higher in the TNBS group than in the control group (P = 0.0296, P respectively). Pixel max tend to be higher in the TNBS group than in the control group but did not reach statistical significance (P = 0.0662). Maximal thickness is significantly increased in the TNBS group compared to the control group (P = 0.0016) while colon diameter is not (P = 0.1904). Maximal thickness and colon diameter were correlated to colon COX-2 expression (P = 0.0093, P = 0.009 respectively) while pixel max was not (P = 0.22). Maximal thickness was significantly increased when inflammation was histologically observed (P = 0.0043) while pixel max and colon diameter did not (P = 0.2452, P = 0.3541, respectively).CONCLUSIONSPECT-CT is feasible and easily distinguished control from colitic rats.

关键词： Crohn’ s disease Colitis Colitis imaging Cyclooxygenase-2 SPECT-computed tomography

Effects of Prandtl and Jacob Numbers and Dimensionless Thermal Conductivity on Velocity Profiles in Media (Porous and Liquid)

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Journal of Modern Physics 2024年第10期15卷 1603-1614页

作者： Momath Ndiaye Madialène Sene Goumbo Ndiaye Department of Hydraulics Rural Engineering Machinery and Renewable Energy UFR Fundamental and Engineering Sciences University of Sine Saloum El Hadj Ibrahima NIASS Kaolack Senegal

In this present study, we analyzed the effects of Prandtl and Jacob numbers and dimensionless thermal conductivity on the velocity profiles in media (porous and liquid). The transfers in the porous medium and the liquid film are described respectively by the improved Wooding model and the classical boundary layer equations. The mesh of the digital domain is considered uniform in the transverse and longitudinal directions. The advection and diffusion terms are discretized with a back-centered and centered scheme respectively. The coupled systems of algebraic equations thus obtained are solved numerically using an iterative line-by-line relaxation method of the Gauss-Seidel type. The results show that the parameters relating to the thermal problem (the dimensionless thermal conductivity, the Prandtl (Pr) and Jacob (Ja) numbers) have no influence on the dimensionless speed, although the thermal and hydrodynamic problems are coupled. Via the heat balance equation. The results obtained show that the parameters relating to the thermal problem have no influence on the dimensionless speed, although the thermal and hydrodynamic problems are coupled via the heat balance equation. So, at first approximation with the chosen constants, we can solve the hydrodynamic problem independently of the thermal problem.

关键词： Condensation Implicit Finite Difference Thin Film Porous Material Model Wooding Vertical Wall

A new visual acuity test on touchpad for vision screening in children

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International Journal of Ophthalmology(English edition) 2020年第9期13卷 1436-1442页

作者： Elsa Di Foggia Noémie Stoll Hélène Meunier Adam rimelé Pascal Ance Pierre-Henri Moreau Claude Speeg-Schatz Arnaud Sauer Ophthalmology Department CHU StrasbourgStrasbourgAlsace 67091France Ophthalmology Department CH ColmarColmarAlsace 68024France Cognitive and Adaptative neuroscience Laboratory StrasbourgAlsace 67000France Plateforme SILABE Strasbourg UniversityAlsace 67207France

AIM:To validate a visual acuity(VA)test application on touchpad in the screening of pediatric population by comparing VA results obtained with conventional ***:A cohort of 101 patients,44 girls and 57 boys with a median of 6.5 years old(3-10 years of age),presenting for eye examinations in Ophthalmology Department(Strasbourg,France)between November 1st,2018,and February 1st,2019 were *** and binocular VA testing was performed on the subject using both a standard test and the touchpad application(Monoyer,"E"or,Pigassou depending of children s capacities).Patients were excluded if they were physically or mentally unable to use the *** duration of each tests,the painfulness,the comprehension,the attention of children during the test and test’s preferences were also ***:There was a good linear correlation and intra-class correlation coefficient[ICC=0.50(0.***.0.64)for binocular acuity,0.74(0.***.0.82)for right eyes and 0.525(0.***.0.66)for left eye].The standard errors of measurement were very low(0.***.0.05.0.08 for binocular VA,right eyes VA and left eyes VA,respectively).There was no difference between two tests for right eye(P=0.126);left eye(P=0.098)and binocular acuity(P=0.085).Non inferiority was proved for all binocular[-0.06(-0.09.-0.03)],right eye[-0.04(-0.07.-0.01)]and left eye[-0.06(-0.09,-0.02)]*** sensitivity and specificity,which correspond to the ability for our app to detect amblyopia,were 92%and 80%***:Our touchpad application represents an efficient and valid test of VA in children with a high specificity to detect visual impairment.

关键词： visual acuity application screening children