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Portable device for the local three-dimensional deformation measurement using a single camera

Science China(Technological Sciences) 2018年第1期61卷 51-60页

作者： mohammed Mokhtar Eisa SHAO XinXing HE XiaoYuan School of Civil Engineering Department of Engineering Mechanics Southeast University

The aim of this paper is to establish and validate a portable device for the local three dimensional deformation measurements using a single camera combined with a triangular prism mirror and two mirrors. The mirrors were utilized to convert a single camera into a stereo image system, which views a test object from two different directions and records the surface images of the test specimen on the two halves of the camera sensor in order to achieve a three-dimensional measurement. The proposed system consists of a single camera and the reflection system was integrated into a portable device to achieve a truly portable, low-cost, local three-dimensional deformation measurement, one-time calibration and easy implementation in situ. The optical design and measurement procedures to obtain the three-dimensional （3D） deformation measurements of the proposed system were described in detail. The efficiency and precision of the proposed system were verified by measuring the displacements of a translated fiat plate. As a practical application, the proposed system is used to measure the out-of-plane displacement of an aluminum circular plate with a central load. Moreover, the normal strain measurement of a plastic beam under symmetric four-point bending via an outer loading frame was also presented. The measurement results are in good accordance with the data obtained by strain gauges. The experimental results revealed that the proposed system was practicable and effective for the local three-dimensional deformation measurement. This system well-suited to both laboratory and field condition and will have significant application in the fields of engineering.

关键词： digital image correlation single camera strain analysis local 3D deformation

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Comparative analysis on the performance of different types of input-and command-shaping controllers in minimizing payload residual vibration of an overhead crane with an inclined supporting track

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International Journal of Mechanical System Dynamics 2024年第1期4卷 22-33页

作者： mohammed Alfares Khaled Alhazza Mechanical Engineering Department College of Engineering and PetroleumKuwait UniversityKuwait CityKuwait

Reducing the effects of external disturbance on overhead crane systems is crucial,as they can impair the controller performance and cause excessive vibrations or oscillations of the *** such external disturbance is the inclination of the supporting track of the crane trolley,which causes the system dynamics model to *** open-loop control strategy is widely utilized to control the payload sway motion and generally does not require any alterations in the physical structure of a system or the installation of sensors and/or *** and command shaping are two common open-loop control techniques applied to control overhead *** this paper,the effect of moving an overhead crane system along an inclined supporting track is *** addition,the ability of different types of input-and command-shaping control schemes to suppress the residual vibrations due to trolley track inclination is *** types of input-shaping controllers,which are double-step,zero vibration,and one command waveform(WF)shaper based on a trigonometric function,are used and tested.A linear equation of motion of the overhead crane resting on an inclined surface is developed to simulate the overhead crane and payload *** effectiveness of the different types of open-loop controllers to suppress residual vibrations is verified by both simulation and experimental *** addition,a new WF command shaper is proposed and designed to overcome track inclination while eliminating payload residual vibration.A comprehensive comparative analysis,both numerically and experimentally,is performed on the new proposed shaper to measure its effectiveness in handling inclination when compared to other types of open-loop *** new shaper outperforms other controllers in eliminating payload residual vibration for a wider range of inclination angles.

关键词： overhead cranes open-loop control input and command shaping payload residual vibrations

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Efficient fall activity recognition by combining shape and motion features

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Computational Visual Media 2020年第3期6卷 247-263页

作者： Abderrazak Iazzi mohammed Rziza Rachid Oulad Haj Thami LRIT RABAT IT CENTERFaculty of SciencesUniversity of Mohammed 5 in RabatMorocco ADMIR LAB IRDARABAT IT CENTERENSIASUniversity of Mohammed 5 in RabatMorocco

This paper presents a vision-based system for recognizing when elderly adults fall.A fall is characterized by shape deformation and high *** represent shape variation using three features,the aspect ratio of the bounding box,the orientation of an ellipse representing the body,and the aspect ratio of the projection *** motion variation,we extract several features from three blocks corresponding to the head,center of the body,and feet using optical *** each block,we compute the speed and the direction of *** activity is represented by a feature vector constructed from variations in shape and motion features for a set of frames.A support vector machine is used to classify fall and non-fall *** on three different datasets show the effectiveness of our proposed method.

关键词： shape motion features

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Yeast-generated CO2:A convenient source of carbon dioxide for mosquito trapping using the BG-Sentinel?traps

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Asian Pacific Journal of Tropical Biomedicine 2017年第10期7卷 896-900页

作者： dhanique c.t.jerry terry mohammed azad mohammed University of the West Indies St AugustineTrinidad and Tobago

Objectives: To evaluates carbon dioxide(CO_2) production from yeast/sugar mixtures and its efficiency as an attractant in BG-Sentinel ***: The rate of CO_2 production was optimized for different yeast/sugar *** optimized mixture was then used as bait in BG-Sentinel traps. The efficiency of this bait was then compared to octenol baited ***: The yeast/sugar(5g: 280g) in 300 m L water generated the highest volume of CO_2. The CO_2 baited traps caught significantly more mosquitoes than octenol baited ***: Yeast-produced CO_2 can effectively replace octenol baits in BG *** will significantly reduce costs and allow sustainable mass-application of the CO_2 baited traps in large scale surveillance programs.

关键词： Trinidad and Tobago Carbon dioxide bait BG sentinel trap Attractant

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Thermal Conductivity of Room Temperature Deep Eutectic Solvents

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Journal of Thermal Science 2021年第6期30卷 1960-1972页

作者： ALBAYATI Noor KADHOM mohammed ABDULLAH Ghassan SALIH Suhaib Department of Science College of Basic EducationUniversity of WasitWasit 52005Iraq Department of Environmental Science College of Energy and Environmental ScienceAl-Karkh University of ScienceBaghdad 31020Iraq Department of Chemical Engineering University of TikritSaladin 34001Iraq

As deep eutectic solvents(DESs)became a prevalent category of materials,reporting their physical and chemical properties turned to be *** this work,a database of the thermal conductivity of 39 DESs was experimentally investigated in a temperature range of 25℃to 60℃,since this property was not broadly reported *** the thermal conductivity is a significant approach to obtain the fluids'heat transfer coefficients,which are essential for fluid heat transfer applications and equipment *** selection of the reported DESs was based on their liquid phase status at room temperature and ***,the thermal conductivity was studied as a function of temperature and ***,the data were fit with the conventional equations to predict the thermal conductivity value at a certain *** highest R^(2) was selected to identify the best behavior with the common types of *** was found that the thermal conductivity reduced by raising the temperature,which was attributed to the enhancement that occurred in electrons'randomness and reduction in electrons'free ***,as the temperature rises up,the density decreases,and molecular distance *** contained choline chloride showed higher thermal conductivity stability than other *** an opposite scenario was noticed for glycerol and ethylene glycol DESs due to the possibility of generating water.

关键词： deep eutectic solvents thermal conductivity physical properties green solvents

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Production of Ryazhenka,a traditional Ukrainian fermented baked milk,by using electro-activated whey as supplementing ingredient and source of lactulose

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Food Bioscience 2022年第2期46卷 221-230页

作者： Sabina Aidarbekova mohammed Aider Department of Food Sciences Universit´e LavalQuebecQCG1V 0A6Canada Institute of Nutrition and Functional Foods INAF Universit´e LavalQuebecQCG1V 0A6Canada Department of Soil Sciences and Agri-food Engineering Universit´e LavalQuebecQCG1V 0A6Canada

In this work,electro-activated whey(EAW)was used as ingredient in the preparation of Ryazhenka,a fermented baked milk,at a supplementation level of 3 and 9%.Fermentation kinetics,viscosity,color,antioxidant capacity,and protein profiles of the final product were ***,effect of electro-activation onβ-lactoglobulin allergenicity was evaluated by a specific ELISA *** results showed that addition of electro-activated whey as supplementing ingredient is technologically feasible in the process of Ryazhenka *** fermentation kinetics showed that this process was in the technologically accepted interval even if the addition of EAW delayed the fermentation *** viscosity study showed that addition of EAW permitted to obtain a final product with good followability corresponding to good consistency of drinkable dairy ***,addition of EAW prevented syneresis during the refrigerated storage at 4℃ and enriched the product with lactulose which is a recognized *** chromatic evaluation of the final product showed a compatibility of EAW with Ryazhenka which is known for its specific yellowish-brownish *** or EAW significantly improved the antioxidant capacity of the Ryazhenka with values of IC_(50)DPPH=2.54±0.02 and IC_(50)PFRAP=244.03±28.83 for the Ryazhenka produced by adding 9%EAW to the milk after the baking process and prior to ***,by using aβ-lactoglobulin specific ELISA test,this study showed a significant decrease of whey and pureβ-lactoglobulin allergenicity by 95%.This decrease was also observed in Ryazhenka supplemented with 9%EAW but at lower ***,it can be concluded that electro-activated whey can be considered as a promising functional ingredient containing a prebiotic lactulose as functional ingredient in the dairy industry.

关键词： Electro-activated whey Ryazhenka Lactulose Prebiotic Allergenicity reduction

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First-principles study of the new potential photovoltaic absorber:Cu_2MgSnS_4 compound

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Chinese Physics B 2017年第7期26卷 294-304页

作者： Belmorsli Bekki Kadda Amara mohammed El Keurti Laboratoire d'étude physico-chimique Université Dr.Moulay Tahar de Saida

The structural, electronic, optical, and elastic properties of Cu_2MgSnS_4 in four crystalline phases（wurtzite-stannite（WS）, stannite（ST）, kesterite（KS）, and primitive-mixed Cu Au（PMCA）） are investigated using density functional theory（DFT） in the framework of the full potential linearized augmented plane wave plus local-orbitals（FP-LAPW＋lo） method within the generalized gradient approximation based on the Perdew 2008 functional（GGA-PBEsol）. For each phase, the structural parameters, bulk modulus, and its pressure derivative are calculated. The relative stability of these phases is also discussed. In addition, the elastic constants have been calculated in order to investigate the mechanical stability of all phases. Moreover, the anisotropy factor, shear modulus, Young＇s modulus, Lame＇s coefficient, and Poisson＇s ratio have been estimated from the calculated single crystalline elastic constants. For the band structure, the density of states and optical properties of the exchange and correlation effects are treated by the Tran-Blaha modified Becke-Johnson potential to give a better description of the band-gap energies and optical spectra. The obtained results are compared with available experimental data and to other theoretical calculations.

关键词： quaternary chalcogenide semiconductor elastic constants electronic properties optical properties

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Hydrological and mechanical properties of plants to predict suitable legume species for reinforcing soil

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Chinese Science Bulletin 2014年第35期59卷 5123-5128页

作者： mohammed Saifuddin Normaniza Osman Institute of Biological Sciences Faculty of ScienceUniversity of Malaya

Plants have considerable hydrological and mechanical impacts on ***,there are lack of documentation and limited understanding on the hydrological and mechanical impacts of tropical legume ***,this study was aimed to investigate the hydrological and mechanical properties of three selected legume plants,Leucaena leucocephala,Adenanthera pavonina and Peltophorum *** hydrological aspect,the study results indicated that soil on which the *** was grown had the highest transpiration rate,water absorption rate(WAR) and soil matric suction(SMS).In terms of mechanical characteristics,*** exhibited the highest root tensile strength and cellulosic components in the ***,*** also showed a higher root biomass,root length and fine roots than *** and *** leaf area index(LAI) strongly correlated with SMS(R2= 0.74),indicating that high LAI improved *** high root tensile strength and fine roots of *** make this species special for growing as a soil reinforcing *** results suggested that *** exhibited outstanding hydrological and mechanical properties and can be a potential plant for the soil reinforcement program.

关键词：土壤加固豆科植物水文性能预测力学机械冲击抗拉强度叶面积指数

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The effects of cross-diffusion and radiation on mixed convection from a vertical flat plate embedded in a fluid-saturated porous medium in the presence of viscous dissipation

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Propulsion and Power Research 2016年第2期5卷 149-163页

作者： mohammed A.mohammed Ahmed mohammed E.mohammed Ahmed A.Khidir Faculty of Technology of Mathematical Sciences and Statistics Alneelain UniversityP.O.Box 12702KhartoumSudan

In this paper,we propose a new application of a recent semi-numericalsuccessive linearization method(SLM)in solving highly coupled,nonlinear boundaryvalue *** method is presented in detail by solving the problem of steady flowof mixed convection and an incompressible viscous hydromagnetic fluid from a verticalflat plate embedded in a fluid-saturated porous *** governing partial differentialequations are transformed into a system of ordinary differential equations and then solvedby *** effects of different physical parameters on the velocity,temperature,andconcentration profiles are determined and *** skin-friction,and heat and masstransfer coefficients have been obtained and analyzed for various physical *** results are presented numerically through graphs and tables for both assistingand opposing flows to observe the effects of various parameters encountered in the equations.

关键词： Successive linearization method Mixed convection Cross-diffusion Heat and mass transfer Viscous dissipation

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Lattice Boltzmann Simulation of Free-Surface Temperature Dispersion in Shallow Water Flows

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Advances in Applied Mathematics and Mechanics 2009年第3期1卷 415-437页

作者： mohammed Seaid Guido Thommes School of Engineering University of DurhamSouth RoadDurham DH13LEUK Fraunhofer-Institut fur Techno-und Wirtschaftsmathematik 67663 KaiserslauternGermany

We develop a lattice Boltzmann method for modeling free-surface temperature dispersion in the shallow water *** governing equations are derived from the incompressible Navier-Stokes equations with assumptions of shallow water flows including bed frictions,eddy viscosity,wind shear stresses and Coriolis *** thermal effects are incorporated in the momentum equation by using a Boussinesq *** dispersion of free-surface temperature is modelled by an advection-diffusion *** distribution functions are used in the lattice Boltzmann method to recover the flow and temperature variables using the same lattice *** upwind discretization procedures nor Riemann problem solvers are needed in discretizing the shallow water *** addition,the source terms are straightforwardly included in the model without relying on well-balanced techniques to treat flux gradients and source *** validate the model for a class of problems with known analytical solutions and we also present numerical results for sea-surface temperature distribution in the Strait of Gibraltar.

关键词： Shallow water flows free-surface temperature lattice Boltzmann method advection-diffusion equation strait of Gibraltar

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