In this paper,an adaptive cubic regularisation algorithm based on affine scaling methods(ARCBASM)is proposed for solving nonlinear equality constrained programming with nonnegative constraints on variables.From the op...In this paper,an adaptive cubic regularisation algorithm based on affine scaling methods(ARCBASM)is proposed for solving nonlinear equality constrained programming with nonnegative constraints on variables.From the optimality conditions of the problem,we introduce appropriate affine matrix and construct an affine scaling ARC subproblem with linearized constraints.Composite step methods and reduced Hessian methods are applied to tackle the linearized constraints.As a result,a standard unconstrained ARC subproblem is deduced and its solution can supply sufficient decrease.The fraction to the boundary rule maintains the strict feasibility(for nonnegative constraints on variables)of every iteration point.Reflection techniques are employed to prevent the iterations from approaching zero too early.Under mild assumptions,global convergence of the algorithm is analysed.Preliminary numerical results are reported.展开更多
Based on the split hopkinson pressure bar(SHPB)tests results,the cubic specimens have been numerically modeled in this paper to investigate the impact of key factors,such as the rise time,duration,and incident pulse s...Based on the split hopkinson pressure bar(SHPB)tests results,the cubic specimens have been numerically modeled in this paper to investigate the impact of key factors,such as the rise time,duration,and incident pulse shape,on achieving stress uniformity.After analysis,the paper provides actionable methods aimed at optimizing the conditions for stress uniformity within the cubic specimen.Finally,the lateral inertia effect of cubic specimen has been scrutinized to address the existing gap in this academic area.展开更多
Ion-exchange Polymer-Metal Composites(IPMCs)gain huge attentions due to large deformation,rapid electromechanical response,and high energy conversion efficiency.Deflection of IPMC arises from the volumetric swelling e...Ion-exchange Polymer-Metal Composites(IPMCs)gain huge attentions due to large deformation,rapid electromechanical response,and high energy conversion efficiency.Deflection of IPMC arises from the volumetric swelling effect induced by the concentration gradient of hydrated cations between the two electrodes,thus the volume of hydrated cation deter-mines the motion magnitude and direction of IPMC.H ion is one of the most commonly used driving cations for IPMC.However,due to its unique characteristics,particularly the inability to accurately quantify its hydration volume,existing literatures primarily focus on the physical driving models for metallic cations,i.e.,Na+,no driving model for the H ion is reported until now.This paper proposes a novel model of H ion escape from the water's body-centered cubic lattice to count the hydration volume.Number(n)of water molecules carried by the H ion is solved by combining the Lennard-Jones potential energy function with Maxwell's velocity distribution.The specific n value is equivalent to 4.04 for the H ion inside Nafion electrolyte under a 3.0 V DC electric field.Substituting it into the classic Friction Model(proposed by Tadokoro et al.at 2000),actuation behaviors of H ion driven IPMC were therefore achieved through Matlab calculations and Abaqus simulations.The calculated results of dynamic displacement and force highly match to the experimental data form the Nafion IPMC actuator driven by same electric field,showing a highly reliability of the established escape model.展开更多
This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to d...This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to determine which configuration can provide better heat and mass transfer and lower entropy production,while ensuring cost efficiency.This work bridges the gap be-tween academic research and industrial feasibility by incorporating cost analysis,entropy generation,and thermal efficiency.To compare the velocity,temperature,and concentration profiles,we examine two ternary nanofluids,i.e.,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O,while considering the shape of nanoparticles.The velocity slip and Soret/Dufour effects are taken into consideration.Furthermore,regression analysis for Nusselt and Sherwood numbers of the model is carried out.The Runge-Kutta fourth-order method with shooting technique is employed to acquire the numerical solution of the governed system of ordinary differential equations.The flow pattern attributes of ternary nanofluids are meticulously examined and simulated with the fluc-tuation of flow-dominating parameters.Additionally,the influence of these parameters is demonstrated in the flow,temperature,and concentration fields.For variation in Eckert and Dufour numbers,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher temperature than TiO_(2)+SiO_(2)+Cu/H_(2)O.The results obtained indicate that the ternary nanofluid TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher heat transfer rate,lesser entropy generation,greater mass transfer rate,and lower cost than that of TiO_(2)+SiO_(2)+Cu/H_(2)O ternary nanofluid.展开更多
Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives ...Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.展开更多
In this paper,we examine the functions a(n)and b(n),which respectively represent the number of cubic partitions and cubic partition pairs.Our work leads to the derivation of asymptotic formulas for both a(n)and b(n).A...In this paper,we examine the functions a(n)and b(n),which respectively represent the number of cubic partitions and cubic partition pairs.Our work leads to the derivation of asymptotic formulas for both a(n)and b(n).Additionally,we establish the upper and lower bounds of these functions,factoring in the explicit error terms involved.Crucially,our findings reveal that a(n)and b(n)both satisfy several inequalities such as log-concavity,third-order Turan inequalities,and strict log-subadditivity.展开更多
The rock-salt cubic SnSe compound with multiple valleys and inherent low thermal conductivity is considered to be a promising thermoelectric compound.In this study,heterogeneous Pb atoms were strategically introduced ...The rock-salt cubic SnSe compound with multiple valleys and inherent low thermal conductivity is considered to be a promising thermoelectric compound.In this study,heterogeneous Pb atoms were strategically introduced into the lattice of cubic SnSe matrix,synergistically adjusting the thermoelectric transport properties of samples by optimizing hole carrier concentration(n)and suppressing thermal conductivity(κ_(tot)).When the doping content reached 0.08 mol,the peak power factor(PF)at 300 K increased to 20.00μW·cm^(-1)·K^(-2).The growing internal microstrain induced by the differences in atomic size strengthened the phonon scattering and effectively reduced the lattice thermal conductivity(κ_(L)).With further decoupling of the electrical and thermal transport properties,a peak thermoelectric figure of merit(ZT)of 0.82 and an average ZT of 0.42(300-750 K)were achieved in the samples doped with 0.10 mol Pb.These findings highlight the effectiveness of the selected dopants and demonstrate their synergy in improving the performance of thermoelectric materials.展开更多
基金Supported by the National Natural Science Foundation of China(12071133)Natural Science Foundation of Henan Province(252300421993)Key Scientific Research Project of Higher Education Institutions in Henan Province(25B110005)。
文摘In this paper,an adaptive cubic regularisation algorithm based on affine scaling methods(ARCBASM)is proposed for solving nonlinear equality constrained programming with nonnegative constraints on variables.From the optimality conditions of the problem,we introduce appropriate affine matrix and construct an affine scaling ARC subproblem with linearized constraints.Composite step methods and reduced Hessian methods are applied to tackle the linearized constraints.As a result,a standard unconstrained ARC subproblem is deduced and its solution can supply sufficient decrease.The fraction to the boundary rule maintains the strict feasibility(for nonnegative constraints on variables)of every iteration point.Reflection techniques are employed to prevent the iterations from approaching zero too early.Under mild assumptions,global convergence of the algorithm is analysed.Preliminary numerical results are reported.
基金Funded by the National Natural Science Foundation of China(Nos.52278518 and 51938011)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.24KJB560021)。
文摘Based on the split hopkinson pressure bar(SHPB)tests results,the cubic specimens have been numerically modeled in this paper to investigate the impact of key factors,such as the rise time,duration,and incident pulse shape,on achieving stress uniformity.After analysis,the paper provides actionable methods aimed at optimizing the conditions for stress uniformity within the cubic specimen.Finally,the lateral inertia effect of cubic specimen has been scrutinized to address the existing gap in this academic area.
基金National Natural Science Foundations of China(52275295)Central Plains Science and Technology Innovation Leading Talents(234200510026).
文摘Ion-exchange Polymer-Metal Composites(IPMCs)gain huge attentions due to large deformation,rapid electromechanical response,and high energy conversion efficiency.Deflection of IPMC arises from the volumetric swelling effect induced by the concentration gradient of hydrated cations between the two electrodes,thus the volume of hydrated cation deter-mines the motion magnitude and direction of IPMC.H ion is one of the most commonly used driving cations for IPMC.However,due to its unique characteristics,particularly the inability to accurately quantify its hydration volume,existing literatures primarily focus on the physical driving models for metallic cations,i.e.,Na+,no driving model for the H ion is reported until now.This paper proposes a novel model of H ion escape from the water's body-centered cubic lattice to count the hydration volume.Number(n)of water molecules carried by the H ion is solved by combining the Lennard-Jones potential energy function with Maxwell's velocity distribution.The specific n value is equivalent to 4.04 for the H ion inside Nafion electrolyte under a 3.0 V DC electric field.Substituting it into the classic Friction Model(proposed by Tadokoro et al.at 2000),actuation behaviors of H ion driven IPMC were therefore achieved through Matlab calculations and Abaqus simulations.The calculated results of dynamic displacement and force highly match to the experimental data form the Nafion IPMC actuator driven by same electric field,showing a highly reliability of the established escape model.
基金supported by DST-FIST(Government of India)(Grant No.SR/FIST/MS-1/2017/13)and Seed Money Project(Grant No.DoRDC/733).
文摘This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to determine which configuration can provide better heat and mass transfer and lower entropy production,while ensuring cost efficiency.This work bridges the gap be-tween academic research and industrial feasibility by incorporating cost analysis,entropy generation,and thermal efficiency.To compare the velocity,temperature,and concentration profiles,we examine two ternary nanofluids,i.e.,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O,while considering the shape of nanoparticles.The velocity slip and Soret/Dufour effects are taken into consideration.Furthermore,regression analysis for Nusselt and Sherwood numbers of the model is carried out.The Runge-Kutta fourth-order method with shooting technique is employed to acquire the numerical solution of the governed system of ordinary differential equations.The flow pattern attributes of ternary nanofluids are meticulously examined and simulated with the fluc-tuation of flow-dominating parameters.Additionally,the influence of these parameters is demonstrated in the flow,temperature,and concentration fields.For variation in Eckert and Dufour numbers,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher temperature than TiO_(2)+SiO_(2)+Cu/H_(2)O.The results obtained indicate that the ternary nanofluid TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher heat transfer rate,lesser entropy generation,greater mass transfer rate,and lower cost than that of TiO_(2)+SiO_(2)+Cu/H_(2)O ternary nanofluid.
基金supported by the National Natural Science Foundation of China,Nos.82071426,81873784Clinical Cohort Construction Program of Peking University Third Hospital,No.BYSYDL2019002(all to DF)。
文摘Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.
基金supported by the National Natural Science Foundation of China(12371327)the Natural Science Foundation of Chongqing(cstc2021jcyj-msxmX0107).
文摘In this paper,we examine the functions a(n)and b(n),which respectively represent the number of cubic partitions and cubic partition pairs.Our work leads to the derivation of asymptotic formulas for both a(n)and b(n).Additionally,we establish the upper and lower bounds of these functions,factoring in the explicit error terms involved.Crucially,our findings reveal that a(n)and b(n)both satisfy several inequalities such as log-concavity,third-order Turan inequalities,and strict log-subadditivity.
基金supported by Taishan Scholar Program of Shandong Province(No.tsqn202306225)Shandong Postdoctoral Science Foundation(SDBX2023025)+2 种基金Leader of Scientific Research Studio Program of Jinan(No.2021GXRC082)University of Jinan Disciplinary Cross-Convergence Construction Projects 2023(Nos.XKJC-202301 and XKJC-202311)Jinan City-School Integration Development Strategy Project(Nos.JNSX2023015 and JNSX2023018).
文摘The rock-salt cubic SnSe compound with multiple valleys and inherent low thermal conductivity is considered to be a promising thermoelectric compound.In this study,heterogeneous Pb atoms were strategically introduced into the lattice of cubic SnSe matrix,synergistically adjusting the thermoelectric transport properties of samples by optimizing hole carrier concentration(n)and suppressing thermal conductivity(κ_(tot)).When the doping content reached 0.08 mol,the peak power factor(PF)at 300 K increased to 20.00μW·cm^(-1)·K^(-2).The growing internal microstrain induced by the differences in atomic size strengthened the phonon scattering and effectively reduced the lattice thermal conductivity(κ_(L)).With further decoupling of the electrical and thermal transport properties,a peak thermoelectric figure of merit(ZT)of 0.82 and an average ZT of 0.42(300-750 K)were achieved in the samples doped with 0.10 mol Pb.These findings highlight the effectiveness of the selected dopants and demonstrate their synergy in improving the performance of thermoelectric materials.
