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Optimization of chemistry and process parameters for control of intermetallic formation in Mg sludges

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Journal of Magnesium and Alloys 2024年第4期12卷 1431-1448页

作者： Y.Fu G.G.Wang A.Hu Y.Li K.B.Thacker J.P.Weiler H.Hu Department of Mechanical Automotive and Materials EngineeringUniversity of Windsor401 Sunset AveWindsorOntario N9B 3P4Canada Global Technology Centre Meridian Lightweight Technologies25 MacNab AveStrathroyOntario N7G 4H6Canada

Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important ***,very often it is overlooked by academia,original equipment manufacturers(OEM),metal ingot producers and even die *** aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process *** Al8Mn5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn *** design of experiment(DOE)technique,Taguchi method,was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al,Mn,Fe,and different process parameters,holding temperature and holding *** sludge yield(SY)and intermetallic size(IS)was selected as two *** optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,690℃ for the holding temperature and holding at 30 mins for the holding time,*** best combination for smallest intermetallic size were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,630℃ for the holding temperature and holding at 60 mins for the holding time,*** groups of sludge factors,Chemical Sludge(CSF),Physical Sludge(PSF)and Comprehensive Sludge Factors(and CPSF)were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg *** CPSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction,as the prediction of the PSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental *** Chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity,of which process parameters could be fixed *** Physical Sludge Factor could be used f

关键词： Magnesium sludge Al-Mn intermetallic Optimization Taguchi method Sludge factor Chemical composition Process parameter

A robust vector tracking loop structure based on potential bias analysis

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Chinese Journal of Aeronautics 2024年第4期37卷 405-420页

作者： Qiongqiong JIA Yiran LUO Bing XU Li-Ta HSU Renbiao WU Tianjin Key Lab for Advanced Signal Processing Civil Aviation University of ChinaTianjin 300300China Interdisciplinary Division of Aeronautical and Aviation Engineering The Hong Kong Polytechnic University999077Hong KongChina Department of Geomatics Engineering University of CalgaryCalgary T2N1N4Canada

This paper proposes a robust vector tracking loop structure based on potential bias analysis. The influence of four kinds of biases on the existing two implementations of Vector Tracking Loops(VTLs) is illustrated by theoretical analysis and numerical simulations, and the following findings are obtained. Firstly, the initial user state bias leads to steady navigation solution bias in the relative VTL, while new measurements can eliminate it in the absolute VTL. Secondly, the initial code phase bias is transferred to the following navigation solutions in the relative VTL, while new measurements can eliminate it in the absolute VTL. Thirdly, the user state bias induced by erroneous navigation solution of VTLs can be eliminated by both of the two VTLs. Fourthly,the multipath/nLOS likely affects the two VTLs, and the induced tracking bias in the duration of the multipath/nLOS would decrease the performance of VTLs. Based on the above analysis,a robust VTL structure is proposed, where the absolute VTL is selected for its robustness to the two kinds of initialization biases;meanwhile, the instant bias detection and correction method is used to improve the performance of VTLs in the duration of the multipath/nLOS. numerical simulations and experimental results verify the effectiveness of the proposed robust VTL structure.

关键词： Global navigation Satellite System(GnSS) Vector Tracking Loop(VTL) Multipath non-Line-of-Sight(nLOS) Tracking bias propagation Least Absolute Shrinkage and Selection Operator(LASSO)

Suitability of SDn and MEC to facilitate digital twin communication over LTE-A

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Digital Communications and networks 2024年第2期10卷 347-354页

作者： Hikmat Adhami Mohammad Alja’afreh Mohamed Hoda Jiaqi Zhao Yong Zhou Abdulmotaleb El Saddik Mohamed bin Zayed University of Artificial Intelligence Masdar CityAbu DhabiUnited Arab Emirates School of Computer Science and Technology China University of Mining and TechnologyXuzhou221116China School of Electrical Engineering and Computer Science University of OttawaOttawaONK1N 6N5Canada

Haptic is the modality that complements traditional multimedia,i.e.,audiovisual,to evolve the next wave of innovation at which the Internet data stream can be exchanged to enable remote skills and control *** will require ultra-low latency and ultra-high reliability to evolve the mobile experience into the era of Digital Twin and Tactile *** the 5th generation of mobile networks is not yet widely deployed,Long-Term Evolution(LTE-A)latency remains much higher than the 1 ms requirement for the Tactile Internet and therefore the Digital *** work investigates an interesting solution based on the incorporation of Software-defined networking(SDn)and Multi-access Mobile Edge Computing(MEC)technologies in an LTE-A network,to deliver future multimedia applications over the Tactile Internet while overcoming the QoS *** network scenarios were designed and simulated using Riverbed modeler and the performance was evaluated using several time-related Key Performance Indicators(KPIs)such as throughput,End-2-End(E2E)delay,and *** best scenario possible is clearly the one integrating MEC and SDn approaches,where the overall delay,jitter,and throughput for haptics-attained 2 ms,0.01 ms,and 1000 packets per *** results obtained give clear evidence that the integration of,both SDn and MEC,in LTE-A indicates performance improvement,and fulfills the standard requirements in terms of the above KPIs,for realizing a Digital Twin/Tactile Internet-based system.

关键词： LTE-A 5G Digital twin Tactile Internet KPIs SDn MEC nFV Haptic

The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 711-724页

作者： F.JAZInI DORCHEH M.GHASSEMI Fuel Cells and nano Systems(FCnS)Laboratory Department of Mechanical EngineeringK.N.Toosi University of TechnologyTehran 19697Iran

In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological *** numerical modeling of acoustic streaming caused by surface acoustic waves in microchannels requires the effect of viscosity to be considered in the equations which complicates the *** this paper,it is shown that the major contribution of viscosity and the horizontal component of actuation is concentrated in a narrow region alongside the actuation *** the inviscid equations are considerably easier to solve,a division into the viscous and inviscid domains would alleviate the computational load *** particles'traces calculated by this approximation are excellently alongside their counterparts from the completely viscous *** is also shown that the optimum thickness for the viscous strip is about 9-fold the acoustic boundary layer thickness for various flow patterns and amplitudes of actuation.

关键词： surface acoustic wave microfluidics numerical simulation particle tracing acoustic streaming

Sustainable ammonia synthesis:An in-depth review of non-thermal plasma technologies

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Journal of Energy Chemistry 2024年第9期96卷 1-38页

作者： Vahid Shahed Gharahshiran Ying Zheng Department of Chemical and Biochemical Engineering Thompson Engineering BuildingWestern UniversityLondonON N6A 5B9Canada

Ammonia serves both as a widely used fertilizer and environmentally friendly energy source due to its high energy density,rich hydrogen content,and emissions-free ***,it offers convenient transportation and storage as a hydrogen *** dominant method used for large-scale ammonia production is the Haber-Bosch process,which requires high temperatures and pressures and is ***,non-thermal plasma offers an eco-friendly alternative for ammonia synthesis,gaining significant *** enables ammonia production at lower temperatures and pressures using plasma *** review provides insights into the catalyst and reactor developments,which are pivotal for promoting ammonia efficiency and addressing existing *** first,the reaction kinetics and mechanisms are introduced to gain a comprehensive understanding of the reaction pathways involved in plasma-assisted ammonia ***,the enhancement of ammonia synthesis efficiency is discussed by developing and optimizing plasma reactors and effective *** effect of other feeding sources,such as water and methane,instead of hydrogen is also ***,the challenges and possible solutions are outlined to facilitate energy-saving and enhance ammonia efficiency in the future.

关键词： nitrogen fixation Ammonia synthesis nH_(3) non-thermal plasma ni Ru catalyst

On-the-fly precision spectroscopy with a dual-modulated tunable diode laser and Hz-level referencing to a cavity

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Advanced Photonics 2024年第4期6卷 36-44页

作者： Shuangyou Zhang Toby Bi Pascal Del’Haye Max Planck Institute for the Science of Light ErlangenGermany Friedrich-Alexander Universität Erlangen-nürnberg Department of PhysicsErlangenGermany

Advances in laser spectroscopy have enabled many scientific breakthroughs in physics,chemistry,biology,and *** frequency combs pushed measurement limits with ultrahigh-frequency accuracy and fast-measurement speed,while tunable-diode-laser spectroscopy is used in scenarios that require high power and continuous spectral *** these advantages of tunable-diode-laser spectroscopy,it is challenging to precisely determine the instantaneous laser frequency because of fluctuations in the scan ***,we demonstrate a simple spectroscopy scheme with a frequencymodulated diode laser that references the laser on-the-fly to a fiber *** fiber cavity's free spectral range is on-the-fly calibrated with sub-10-Hz frequency *** achieve a relative precision of the laser frequency of 2×10^(-8)for an 11-THz frequency range at a measurement speed of 1 THz∕*** is an improvement of more than 2 orders of magnitude compared to existing diode-laser-spectroscopy *** scheme provides precise frequency calibration markers,while simultaneously tracking the instantaneous scan speed of the *** demonstrate the versatility of our method through various applications,including dispersion measurement of a fiber,ultrahigh-Q microresonators,and spectroscopy of a hydrogen fluoride gas *** simplicity,robustness,and low cost of this spectroscopy scheme are valuable for out-of-the-lab applications like lidar and environmental monitoring.

关键词： tunable laser spectroscopy radio-frequency modulation integrated photonics gas spectroscopy frequency comb

Interplay between mesenchymal stromal cells and the immune system after transplantation: implications for advanced cell therapy in the retina

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neural Regeneration Research 2024年第3期19卷 542-547页

作者： María norte-Muñoz David García-Bernal Diego García-Ayuso Manuel Vidal-Sanz Marta Agudo-Barriuso Grupo de Investigación Oftalmología Experimental Departamento de OftalmologíaOptometríaOtorrinolaringología y Anatomía PatológicaFacultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la Salud30120 MurciaSpain Grupo de Investigación Trasplante Hematopoyético y Terapia celular Departamento de Bioquímica e Inmunología.Facultad de MedicinaUniversidad de MurciaInstituto Murciano de Investigación Biosanitaria(IMIB)Campus de Ciencias de la Salud30120 MurciaSpain

Advanced mesenchymal stromal cell-based therapies for neurodegenerative diseases are widely investigated in preclinical *** stromal cells are well positioned as therapeutics because they address the underlying mechanisms of neurodegeneration,namely trophic factor deprivation and *** studies have focused on the beneficial effects of mesenchymal stromal cell transplantation on neuronal survival or functional ***,little attention has been paid to the interaction between mesenchymal stromal cells and the host immune system due to the immunomodulatory properties of mesenchymal stromal cells and the long-held belief of the immunoprivileged status of the central nervous ***,we review the crosstalk between mesenchymal stromal cells and the immune system in general and in the context of the central nervous system,focusing on recent work in the retina and the importance of the type of transplantation.

关键词： adaptive immunity cell therapy central nervous system immune system innate immunity mesenchymal stromal cells neuroregeneration preclinical studies retina transplantation

Determining minimum sample size for the conditioned Latin hypercube sampling algorithm

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Pedosphere 2024年第3期34卷 530-539页

作者： Daniel D.SAURETTE Asim BISWAS Richard J.HECK Adam W.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In digital soil mapping(DSM),a fundamental assumption is that the spatial variability of the target variable can be explained by the predictors or environmental *** to adequately sample the predictors have been well documented,with the conditioned Latin hypercube sampling(cLHS)algorithm receiving the most attention in the DSM *** advances in sampling design,a critical gap remains in determining the number of samples required for DSM *** propose a simple workflow and function coded in R language to determine the minimum sample size for the cLHS algorithm based on histograms of the predictor variables using the Freedman-Diaconis rule for determining optimal bin *** preprocessing was included to correct for multimodal and non-normally distributed data,as these can affect sample size determination from the *** on a user-selected quantile range(QR)for the sample plan,the densities of the histogram bins at the upper and lower bounds of the QR were used as a scaling factor to determine minimum sample *** technique was applied to a field-scale set of environmental covariates for a well-sampled agricultural study site near Guelph,Ontario,Canada,and tested across a range of *** results showed increasing minimum sample size with an increase in the QR *** sample size increased from 44 to 83 when the QR increased from 50% to 95% and then increased exponentially to 194 for the 99%*** technique provides an estimate of minimum sample size that can be used as an input to the cLHS algorithm.

关键词： bin width digital soil mapping normal distribution quantile range sampling design

A Collocation Technique via Pell-Lucas Polynomials to Solve Fractional Differential EquationModel for HIV/AIDS with Treatment Compartment

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 281-310页

作者： Gamze Yıldırım Suayip Yüzbası Department of Mathematics Faculty of ScienceAkdeniz UniversityAntalya07058Turkey Department of Mathematics Faculty of Basic ScienceGebze Technical UniversityKocaeli41400Turkey Department of Mathematics Faculty of ScienceBartın UniversityBartın74100Turkey

In this study,a numerical method based on the Pell-Lucas polynomials(PLPs)is developed to solve the fractional order HIV/AIDS epidemic model with a treatment *** HIV/AIDS mathematical model with a treatment compartment is divided into five classes,namely,susceptible patients(S),HIV-positive individuals(I),individuals with full-blown AIDS but not receiving ARV treatment(A),individuals being treated(T),and individuals who have changed their sexual habits sufficiently(R).According to the method,by utilizing the PLPs and the collocation points,we convert the fractional order HIV/AIDS epidemic model with a treatment compartment into a nonlinear system of the algebraic ***,the error analysis is presented for the Pell-Lucas approximation *** aim of this study is to observe the behavior of five populations after 200 days when drug treatment is applied to HIV-infectious and full-blown AIDS *** demonstrate the usefulness of this method,the applications are made on the numerical example with the help of *** addition,four cases of the fractional order derivative(p=1,p=0.95,p=0.9,p=0.85)are examined in the range[0,200].Owing to applications,we figured out that the outcomes have quite decent ***,we understand that the errors decrease when the value of n *** figures in this study are created in *** outcomes indicate that the presented method is reasonably sufficient and correct.

关键词： Collocation method fractional differential equations HIV/AIDS epidemic model Pell-Lucas polynomials