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Evaporation of a Thin Binary Liquid Film by Forced Convection into Air and superheated steam

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Journal of Thermal science 2010年第4期19卷 346-356页

作者： Abdelaziz Nasr Chokri Debbissi sassi ben Nasrallah LEsTE cole Nationale d'Ingenieurs de MonastirUniversite de MonastirTunisie

This paper deals with a numerical analysis of the evaporation of a thin binary liquid film by forced convection inside a channel constituted by two *** first plate is externally insulated and wetted by a thin water ethylene glycol film while the second is dry and *** first part is concerned with the effects of inlet ambiance conditions and the liquid concentration of ethylene glycol on the distribution of the velocity,temperature,concentrations profiles and the axial variation of the evaporation *** second part is focused on the inversion temperature point of the evaporation of binary liquid *** show that the inversion temperature phenomenon for the evaporation of binary liquid mixture is observed for high liquid concentration of ethylene *** present results show that in the inlet temperature range considered here,the inversion temperature does not exit for the evaporation of pure ethylene glycol.

关键词： Binary liquid film evaporation inversion temperature forced convection combined heat and mass transfer

Analytic Beta-Wavelet Transform-Based Digital Image Watermarking for secure Transmission

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Computers, Materials & Continua 2022年第3期70卷 4657-4673页

作者： Hesham Alhumyani Ibrahim Alrube sameer Alsharif Ashraf Afifi Chokri ben Amar Hala s.El-sayed Osama s.Faragallah Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.O.11099Taif21944Saudi Arabia Department of Electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom32511Egypt Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.11099Taif21944Saudi Arabia

The rapid development in the information technology field has introduced digital watermark technologies as a solution to prevent unauthorized copying and redistribution of *** article introduces a self-embedded image verification and integrity *** images are firstly split into dedicated segments of the same block ***,different Analytic Beta-Wavelet(ABW)orthogonal filters are utilized for embedding a self-segment watermark for image segment using a predefined *** orthogonal filter coefficients are estimated to improve image reconstruction under different block *** conduct a comparative study comparing the watermarked images using three kinds of ABW filters for block sizes 64×64,128×128,and 256×*** embed the watermark using the ABW-based image watermarking method in the 2-level middle frequency sub-bands of the ABW digital image *** imperceptibility and robustness of the ABW-based image watermarking method image is evaluated based on the Peak signal to Noise Ratio(PsNR)and Correlation coefficient *** the implementation results,we came to know that this ABW-based image watermarking method can withstand many image manipulations compared to other existing methods.

关键词： Watermarking ABW median filtering JPEG compression PsNR

synthesis and structural characterization of a new yttrium phosphate: Na_(2.5)Y_(0.5)Mg_7(PO_4)_6 with fillowite-type structure

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Journal of Rare Earths 2010年第4期28卷 481-487页

作者： Hasna Jerbi Mourad Hidouri Mongi ben Amara R.U. Inorganic materials Faculty of Sciences 5019 Monastir Tunisia

A new phosphate, Na2.5Y0.5Mg7(PO4)6 was synthesized as single crystals by the flux method and as a powdered sample by the Pechini technique, and investigated by single crystal X-ray diffraction, charge distribution (CD) and 31P NMR spectroscopy. This compound crystallized in the rhombohedral space group R 3 and its equivalent hexagonal cell had the following parameters: a=1.4976(6) nm, c= 4.2599(7) nm, Z=18. The structure consisted of MgO5, MgO6, YO6, (Na,Y)O8 and NaOx (x=6, 7 and 9) polyhedra which were li...

关键词： phosphate fillowite X-ray diffraction 31P NMR spectroscopy rare earths

Bubble hydrodynamic influence on oxygen transfer rate at presence of cationic and anionic surfactants in electroflotation process

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Journal of Hydrodynamics 2013年第5期25卷 747-754页

作者： KOTTI Mariam KsENTINI Issam ben MANsOUR Lassaad Laboratory of Applied Fluid Mechanics Process Engineering and EnvironmentScience Faculty of Sfax

In this work, the effects of the presence of surfactants in the liquid phase and the hydrodynamic regime of the bubble flow on the oxygen transfer rate were investigated in an electroflotation process in batch mode. The volumetric mass transfer coefficient KLα and the oxygenation capacity were evaluated to improve the performances of the electroflotation process in terms of oxygenation. In order to evaluate the liquid-side mass transfer coefficient KLα the volumetric mass transfer coefficient KLα was dissociated into KL and the specific interracial area （a） since the last one was obtained from the gas hold-up and the bubble diameter. The effect of Reynolds number which define the hydrodynamic of the bubble flow has been also studied. Models of KLa and KL have been established to show the effects of the hydrodynamic parameters and liquid phase characteristics on the oxygen transfer rate.

关键词： electroflotation mass transfer coefficient hydrodynamic parameters surfactant

Nonlinear variable structure excitation and steam valving controllers for power system stability

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控制理论与应用（英文版） 2009年第1期7卷 97-102页

作者： ben WANG Zongyuan MAO school of Electricity Engineering Southwest Jiaotong University Chengdu Sichuan 610013 China College of Automation science and Engineering South China University of Technology Guangzhou Guangdong 510641 China

A set of novel nonlinear variable structure excitation and steam-valving controllers are proposed in this paper. On the basis of the classical dynamic equations of a generator, excitation control and steam valving control are simultaneously considered. Design of these controllers combines the differential geometry theory with the variable structure controlling theory. The mathematical model in the form of ＂an affine nonlinear system＂ is set up for the control design of a large-scale power plant. The dynamic performance of the nonlinear variable structure controllers proposed for a single machine connected to an infinite bus power system is simulated. simulation results show that the nonlinear variable structure excitation and steam-valving controllers give satisfactory dynamic performance and good robustness.

关键词： Excitation control Nonlinear control steam valving control Variable structure control

Convergence and error bounds of adaptive filtering under model structure and regressor uncertainties

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控制理论与应用（英文版） 2012年第2期10卷 144-151页

作者： ben G. FITZPATRICK Tempest Technologies 8939 south sepulveda Boulevard Suite 506 Los AngelesCA 90045U.S.A. Department of Mathematics Loyola Marymount UniversityLos AngelesCA 90045U.S.A.

Adaptive filtering algorithms are investigated when system models are subject to model structure errors and regressor signal perturbations. system models for practical applications are often approximations of high-order or nonlinear systems, introducing model structure uncertainties. Measurement and actuation errors cause signal perturbations, which in turn lead to uncertainties in regressors of adaptive filtering algorithms. Employing ordinary differential equation （ODE） methodologies, we show that convergence properties and estimation bias can be characterized by certain differential inclusions. Conditions to ensure algorithm convergence and bounds on estimation bias are derived. These findings yield better understanding of the robustness of adaptive algorithms against structural and signal uncertainties.

关键词： Adaptive filtering structural uncertainties Robustness Estimation bias

Hadron productions and jet substructures associated with Z^(0)/γ in Pb+Pb collisions at the LHC

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science China(Physics,Mechanics & Astronomy) 2023年第12期66卷 77-89页

作者： shan-Liang Zhang Hongxi Xing ben-Wei Zhang Key Laboratory of Atomic and subatomic structure and Quantum Control(MOE) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of MatterInstitute of Quantum MatterSouth China Normal UniversityGuangzhou 510006China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Guangdong Provincial Key Laboratory of Nuclear ScienceSouthern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou 510006China Guangdong-Hong Kong Joint Laboratory of Quantum Matter Southern Nuclear Science Computing CenterSouth China Normal UniversityGuangzhou 510006China Institute of Particle Physics and Key Laboratory of Quarks and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China

We carry out a detailed study of medium modifications on Z^(0)/γ+hadron correlations as well as jet substructures in association with Z^(0)/γ in Pb+Pb collisions with √s_(NN)=5.02TeV at the *** utilize the linear Boltzmann transport(LBT)model to simulate the jet-medium interactions and medium response,and an extended cluster hadronization model to investigate the nonperturbative transition of quarks and gluons into final hadrons in heavy-ion *** hadronization effect,we can well describe Z^(0)/γ+hadrons correlations and Z^(0)/γ-tagged jet substructures in both p+p and Pb+Pb collisions *** modification on jet profile and jet fragmentation functions indicate that particles carrying a large fraction of the jet momentum are generally closely aligned with the jet axis,whereas low-momentum particles are observed to have a much broader angular distribution relative to jet axis in Pb+Pb collisions due to jet-medium *** particular,we find that Z^(0)/γ-tagged hadron correlations are sensitive to the soft particles from the dense medium and medium response,while jet-substructures show weak dependence on those soft hadrons with only a fraction of them falling inside the jet area.

关键词： relativistic heavy-ion collisions jet quenching hadronization jet substructures

Accelerating Optimization Design of Bio-inspired Interlocking structures with Machine Learning

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Acta Mechanica solida sinica 2023年第6期36卷 783-793页

作者： Zhongqiu Ding Hong Xiao Yugang Duan ben Wang school of Mechanical Engineering State Key Lab for Manufacturing Systems EngineeringXi’an Jiaotong UniversityXi’an 710049China

structural connections between components are often weak areas in engineering *** nature,many biological materials with remarkablemechanical performance possess flexible and creative *** this work,we propose a novel bioinspired interlocking tab considering both the geometry of the tab head and neck,and demonstrate a new approach to optimize the bio-inspired interlocking structures based on machine *** neural networks for different optimization objectives are developed and trained using a database of thousands of interlocking structures generated through finite element *** show that the proposed method is able to achieve accurate prediction of the mechanical response of any given interlocking *** optimized designs with different optimization objectives,such as strength,stiffness,and toughness,are obtained efficiently and *** optimum design predicted by machine learning is approximately 7.98 times stronger and 2.98 times tougher than the best design in the training set,which are validated through additive manufacturing and experimental *** machine learning-based optimization approach developed here can aid in the exploration of the intricate mechanism behind biological materials and the discovery of new material designs boasting orders of magnitude increase in computational efficacy over conventional methods.

关键词： Interlocking structure Performance prediction Additive manufacturing Artificial neural network Finite element analysis

spiral volumetric optoacoustic tomography visualizes multi-scale dynamics in mice

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Light(science & Applications) 2016年第1期5卷 104-111页

作者： X Luís Deán-ben Thomas F Fehm steven J Ford sven Gottschalk Daniel Razansky Institute for Biological and Medical Imaging(IBMI) Helmholtz Center Munich85764 NeuherbergGermany school of Medicine and school of Bioengineering Technical University of Munich81675 MunichGermany

Imaging dynamics at different temporal and spatial scales is essential for understanding the biological complexity of living organisms,disease state and *** imaging has been shown to offer exclusive applicability across multiple scales with excellent optical contrast and high resolution in deep-tissue ***,efficient visualization of multi-scale dynamics remained difficult with state-of-the-art systems due to inefficient trade-offs between image acquisition time and effective field of ***,we introduce the spiral volumetric optoacoustic tomography technique that provides spectrally enriched highresolution contrast across multiple spatiotemporal *** vivo experiments in mice demonstrate a wide range of dynamic imaging capabilities,from three-dimensional high-frame-rate visualization of moving organs and contrast agent kinetics in selected areas to whole-body longitudinal studies with unprecedented image *** newly introduced paradigm shift in imaging of multi-scale dynamics adds to the multifarious advantages provided by the optoacoustic technology for structural,functional and molecular imaging.

关键词： multi-scale dynamics multi-spectral imaging optoacoustic tomography real-time imaging whole-body imaging