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剪切波弹性成像评估慢性肝病肝纤维化:确定准确和理想的测量位置

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国际医学放射学杂志 2015年第3期 275-275页

作者： a.e.samir M.Dhyani A.Vij A.K.Bhan e.F.Halpern J.MendezNavarro 丁静 Department of Radiology Massachusetts General Hospital Harvard Medical School

目的评估剪切波弹性成像(SWe)对弥漫性肝病病人[包括丙型肝炎病毒(HCV)病人]肝纤维化分期的准确性和确定肝脏不同位置SWe测量对肝纤维化分期的相对准确

关键词：肝纤维化 SWe AUC HCV 肝病病人肝疾病剪切波弹性成像脂肪变性

肝局灶性病变经皮介入的光分子成像前瞻性试验

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国际医学放射学杂志 2015年第3期 276-276页

作者： R.A.Sheth R.S.Arellano R.N.Uppot a.e.samir L.Goyal A.X.Zhu 施益洁 Departments of Radiology Massachusetts General Hospital149 13th St Room 2301Charlestown MA 02129

目的为证明光分子成像(OMI)可临床转化应用于肝局灶性病变经皮介入定位。材料与方法本前瞻性、单中心试验符合HIPAA,获伦理审查委员会批准。入选者为怀疑

关键词：肝局灶性病变分子成像经皮

Stabilization and Synchronization of Discrete-time Fractional Chaotic Systems with Non-identical Dimensions

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Acta Mathematicae Applicatae Sinica 2021年第3期37卷 523-538页

作者： samir BeNDOUKHA Department of electrical engineering College of EngineeringYanbuTaibah UniversitySaudi Arabia

This paper investigates the stabilization and synchronization of two fractional chaotic maps proposed recently,namely the 2D fractional Hénon map and the 3D fractional generalized Hénon *** show that although these maps have non–identical dimensions,their synchronization is still *** proposed controllers are evaluated experimentally in the case of non–identical orders or time–varying *** methods are used to illustrate the results.

关键词： discrete chaos fractional discrete calculus Hénon based maps stabilization synchronization

DUALITY OF GeNeRALIZeD DUNKL-LIPSCHITZ SPACeS

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Acta Mathematica Scientia 2017年第6期37卷 1567-1593页

作者： samir KALLeL Department of Mathematics Higher Institute of Computer Sciences and Mathematics of MonastirMonastir University5000 MonastirTunisia

Abstract The aim of this paper is to prove duality and reflexivity of generalized Lipschitz spaces ∧κα,p,q（R）, α ∈R and 1≤〈 p, q ≤∞, in the context of Dunkl harmonic analysis.

关键词： Dunkl operator duality Herz spaces heat transform Dunkl transform gen-eralized Dunkl-Lipschitz spaces

Simulink Behavioral Modeling of a 10-bit Pipelined ADC

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International Journal of Automation and computing 2013年第2期10卷 134-142页

作者： samir Barra Souhil Kouda Abdelghani Dendouga N. e. Bouguechal Advanced electronics Laboratory Department of Electronics University of Batna Avenue Chahid Boukhlouf Mohamed El Hadi05000Batna Algeria Department of electronics University of M'sila M'silaAlgeria Center for Development of Advanced Technologies Microelectronics and Nanotechnology DivisionAugust 20 1956 City BP 17 BabaHassen Algiers Algeria

The increasing architecture complexity of data converters makes it necessary to use behavioral models to simulate their electrical performance and to determine their relevant data features. For this purpose, a specific data converter simulation environment has been developed which allows designers to perform time-domain behavioral simulations of pipelined analog to digital converters （ADCs）. All the necessary blocks of this specific simulation environment have been implemented using the popular Matlab simulink environment. The purpose of this paper is to present the behavioral models of these blocks taking into account most of the pipelined ADC non-idealities, such as sampling jitter, noise, and operational amplifier parameters （white noise, finite DC gain, finite bandwidth, slew rate, and saturation voltages）. Simulations, using a 10-bit pipelined ADC as a design example, show that in addition to the limits analysis and the electrical features extraction, designers can determine the specifications of the basic blocks in order to meet the given data converter requirements.

关键词： Behavioral modeling analog to digital converters (ADCs) pipelined ADC multiple digital to analog converter (MDAC) sample and hold (S/H)

The effects of exhaust air vent location on thermal comfort inside a residential building equipped with an evaporative cooling system

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Building Simulation 2021年第4期14卷 1063-1075页

作者： rmin Saraei samir Farid Moujaes Department of Mechanical engineering College of EngineeringUniversity of Nevada Las VegasLas VegasNV89154USA

The location of exhaust air vents of an evaporative cooling system can have significant effects on providing thermal comfort and controlling humidity, temperature and air distribution in buildings. In the current study, four different strategies have been evaluated for exhaust air vent locations to provide the optimum thermal comfort inside a typical residential house. This study provides a numerical solution for temperature and relative humidity profiles in the residential house and within the living space in each room typically at a height of 1.8 m or less. By evaluating different exhaust air vent locations in a room, the best strategy(ies) to provide more appropriate thermal comfort condition and obtained and as a conclusion, the exhaust vents should be located on furthest wall away from the entrance of the room and in the middle. The results provided in the current study can eventually be applied in the design of evaporative cooler exhaust vent systems in residential buildings and lead to improve the performance of these systems.

关键词： thermal comfort CFD evaporative cooling system exhaust air vents

Finite elementθ-Schemes for the Acoustic Wave equation

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Advances in Applied Mathematics and Mechanics 2011年第2期3卷 181-203页

作者： samir Karaa Department of Mathematics and Statistics Sultan Qaboos UniversityP.O.Box 36Al-Khod 123MuscatSultanate of Oman

In this paper,we investigate the stability and convergence of a family of implicit finite difference schemes in time and Galerkin finite element methods in space for the numerical solution of the acoustic wave *** schemes cover the classical explicit second-order leapfrog scheme and the fourth-order accurate scheme in time obtained by the modified equation *** derive general stability conditions for the family of implicit schemes covering some well-known CFL *** error estimates are *** sufficiently smooth solutions,we demonstrate that the maximal error in the L^(2)-norm error over a finite time interval converges optimally as O(h^(p+1)+∆t^(s)),where p denotes the polynomial degree,s=2 or 4,h the mesh size,and∆t the time step.

关键词： Finite element methods discontinuous Galerkin methods wave equation implicit methods energy method stability condition optimal error estimates

Simulation and analysis of resin flow in injection machine screw

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2008年第3期9卷 338-345页

作者： Ling-feng LI samir MeKID College of Mechanical and energy engineering Zhejiang University Hangzhou 310027 China School of Mechanical Aerospace and Civil Engineering University of Manchester Manchester UK

A method with simulation and analysis of the resin flow in a screw is presented to ease the control of some problems that may affect the efficiency and the quality of the product among existing screws in an injection machine. The physical model of a screw is established to represent the stress, the strain, the relationship between velocity and stress, and the temperature of the cells. In this paper, a working case is considered where the velocity and the temperature distributions at any section of the flow are obtained. The analysis of the computational results shows an ability to master various parameters depending on the specifications.

关键词： Screw Plasticity Velocity distribution Temperature distribution

Spatial Variability and Cartography of Maximum Annual Daily Rainfall under Different Return Periods in Northern Algeria

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Journal of Mountain Science 2015年第6期12卷 1403-1421页

作者： MeDDI Mohamed TOUMI samir National High School of Hydraulic (eNSH)

The estimation of precipitation quantiles has always been an area of great importance to meteorologists, hydrologists, planners and managers of hydrotechnical infrastructures. In many cases, it is necessary to estimate the values relating to extreme events for the sites where there is little or no measurement, as well as their return periods. A statistical approach is the most used in such cases. It aims to find the probability distribution that best fits the maximum daily rainfall values. In our study, 231 rainfall stations were used to regionalize and find the best distribution for modeling the maximum daily rainfall in Northern Algeria. The L-moments method was used to perform a regionalization based on discordance criteria and homogeneity test. It gave rise to twelve homogeneous regions in terms of LCoefficient of variation(L-CV), L-Skewness(L-CS) and L-Kurtosis(L-CK). This same technique allowed us to select the regional probability distribution for each group using the Z statistic. The generalized extreme values distribution(GeV) was selected to model the maximum daily rainfall of 10 groups located in the north of the steppe region and the generalized logistic distribution(GLO) for groups representing the steppes of Central and Western Algeria. The study of uncertainty by the bias and RMSe showed that the regional approach is acceptable. We have also developed maximum daily rainfall maps for 2, 5, 10, 20, 50 and 100 years return periods. We relied on a network of 255 rainfall stations. The spatial variability of quantiles was evaluated by semi-variograms. All rainfall frequency models have a spatial dependence with an exponential model adjusted to the experimental semi-variograms. The parameters of the fitted semi-variogram for different return periods are similar, throughout, while the nugget is more important for high return periods. Maximum daily rainfall increases from South to North and from West to east, and is more significant in the coastal areas of ea

关键词： Annual maximum daily rainfall Regionalisation L-moments Mapping Northern Algeria