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一类Cahn-Hilliard-Navier-Stokes-Oono方程组的Cauchy问题
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作者 张雪 赵晓朋 《曲阜师范大学学报(自然科学版)》 2026年第1期67-72,共6页
研究了一类与两相流体界面扩散运动相关的Cahn-Hilliard-Navier-Stokes-Oono方程组的Cauchy问题.利用能量估计结合负Sobolev模范数估计,证明了方程组Cauchy问题强解的小初值整体存在性,并给出了整体强解高阶导数的衰减估计.
关键词 Cahn-Hilliard-Navier-stokes-Oono方程组 能量估计 CAUCHY问题
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一种求解Stokes问题的深度学习混合方法
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作者 杨楠 刘文艺 +1 位作者 周言信 宋恩彬 《四川大学学报(自然科学版)》 北大核心 2026年第1期58-64,共7页
深度学习Galerkin法(Deep Galerkin Method,DGM)能够高效地逼近偏微分方程的解。受到混合有限元法的启发,本文构建了一种深度学习混合方法,用于求解Stokes系统。该方法通过换元法引入了速度梯度这个新变量,并将深度学习方法和偏微分方... 深度学习Galerkin法(Deep Galerkin Method,DGM)能够高效地逼近偏微分方程的解。受到混合有限元法的启发,本文构建了一种深度学习混合方法,用于求解Stokes系统。该方法通过换元法引入了速度梯度这个新变量,并将深度学习方法和偏微分方程降阶方法结合起来。为了避免使用二阶自动微分,本文将训练得到的深度学习模型专门用于该混合方法,实现对问题的有效近似。本文对损失函数的收敛性及深度学习解的最优性进行了分析。数值算例验证了方法的有效性。 展开更多
关键词 stokes系统 深度学习 GALERKIN法 收敛性分析
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三维可压缩Navier⁃Stokes/Allen⁃Cahn系统滑移边界问题弱解的存在性
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作者 陈冬冬 冯昕奕 陈亚洲 《北京化工大学学报(自然科学版)》 北大核心 2026年第2期126-133,共8页
研究了三维可压缩Navier⁃Stokes/Allen⁃Cahn(NSAC)系统滑移边界问题,该系统描述了具有扩散界面的非混相两相流的流动。在初始能量有限和绝热常数γ>2的条件下,利用Faedo⁃Galerkin近似和弱收敛极限证明了带有Navier⁃slip边界条件的初... 研究了三维可压缩Navier⁃Stokes/Allen⁃Cahn(NSAC)系统滑移边界问题,该系统描述了具有扩散界面的非混相两相流的流动。在初始能量有限和绝热常数γ>2的条件下,利用Faedo⁃Galerkin近似和弱收敛极限证明了带有Navier⁃slip边界条件的初边值问题弱解的全局存在性。 展开更多
关键词 Navier⁃stokes/Allen⁃Cahn系统 滑移边界条件 弱解存在性
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Stokes积分计算大地水准面中央区效应分析
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作者 耿晓燕 赵辉 +2 位作者 郭鑫伟 孟静娟 王文超 《大地测量与地球动力学》 北大核心 2026年第4期481-486,共6页
为分析Stokes积分计算大地水准面中不同奇异积分处理方法的差异,在研究基于圆形近似的传统方法与双二次多项式插值方法的基础上,推导积分半径内Stokes积分的去奇异方法。选择实验区进行计算分析,结果表明,中央区取计算点所在的单个格网... 为分析Stokes积分计算大地水准面中不同奇异积分处理方法的差异,在研究基于圆形近似的传统方法与双二次多项式插值方法的基础上,推导积分半径内Stokes积分的去奇异方法。选择实验区进行计算分析,结果表明,中央区取计算点所在的单个格网时,使用点核数值积分,传统方法与双二次多项式插值法结果相近,去奇异法精度有所改进;平均核数值积分能够提升传统方法与双二次多项式插值法计算精度,而去奇异法变化不大。 展开更多
关键词 stokes积分 大地水准面 中央区效应 奇异积分
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Lipschitz Estimates for the Commutators of Fractional Hardy and Hardy-Littlewood-Pólya Operators on Grand p-adic Variable Herz Spaces
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作者 常云鹏 武江龙 《数学进展》 北大核心 2026年第2期419-430,共12页
In this article,we prove the boundedness for commutators of fractional Hardy and Hardy-Littlewood-Pólya operators on grand p-adic variable Herz spaces,where the symbols of the commutators belong to Lipschitz spaces.
关键词 p-adic field fractional Hardy operator Hardy-Littlewood-Pólya operator grand variable Herz space commutator
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分数阶Navier-Stokes方程的弱Galerkin有限元解
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作者 覃燕梅 段萌萌 +1 位作者 谢春梅 冯民富 《四川大学学报(自然科学版)》 北大核心 2026年第1期72-82,共11页
本文基于弱Galerkin有限元法建立了一种求解时间分数阶Navier-Stokes方程的全离散格式。格式用弱Galerkin有限元法对空间进行离散,分别采用i(i≥1),i-1和i-1次多项式逼近单元内部速度、压力及单元边界上的速度,同时采用有限差分格式对时... 本文基于弱Galerkin有限元法建立了一种求解时间分数阶Navier-Stokes方程的全离散格式。格式用弱Galerkin有限元法对空间进行离散,分别采用i(i≥1),i-1和i-1次多项式逼近单元内部速度、压力及单元边界上的速度,同时采用有限差分格式对时间Caputo分数阶导数进行离散。本文给出了格式的稳定性分析,误差估计及最优估计。数值算例验证了理论结果。 展开更多
关键词 时间分数阶Navier-stokes方程 弱Galerkin有限元 稳定性 误差估计
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Hyponormal Block Toeplitz Operators on the Weighted Bergman Space with Circulant Symbols
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作者 FU Guangyang ZHOU Jiang 《数学进展》 北大核心 2026年第1期183-191,共9页
In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and... In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and G(z)=∑^(N)_(i)=1 A_(−i)z^(i),A_(i)ae culants. 展开更多
关键词 block Toeplitz operator hyponormal weighted Bergman space CIRCULANT COMMUTATOR
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Estimates for p-adic fractional integral operator with rough kernels on grand p-adic Herz-type spaces
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作者 XIA Xiaoxi ZHOU Jiang 《中山大学学报(自然科学版)(中英文)》 北大核心 2026年第2期153-159,共7页
The goal of this paper is to establish the boundedness of the p-adic fractional integral operator with rough kernel I_(β,Ω′)^(p)and its commutators generated by b∈Λ_(γ)(Q_(p)^(n))(0<γ<1)and the I_(β,Ω′... The goal of this paper is to establish the boundedness of the p-adic fractional integral operator with rough kernel I_(β,Ω′)^(p)and its commutators generated by b∈Λ_(γ)(Q_(p)^(n))(0<γ<1)and the I_(β,Ω′)^(p) on grand p-adic Herz spaces. 展开更多
关键词 Lipschitz spaces grand p-adic Herz spaces p-adic fractional integral operator COMMUTATORS
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非齐次不可压缩流体的Navier-Stokes方程的爆破判据
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作者 李玉鸽 任永华 郝惠琴 《广西师范大学学报(自然科学版)》 北大核心 2026年第1期119-125,共7页
本文探讨非齐次不可压缩流体Navier-Stokes方程的爆破判据问题。方程弱解的存在性已得到充分研究,但强解的存在性仍是一个开放问题,特别是对满足特定相容性条件的充分正则数据,目前仅得到局部存在性结果。本文在二维有界光滑域中重点研... 本文探讨非齐次不可压缩流体Navier-Stokes方程的爆破判据问题。方程弱解的存在性已得到充分研究,但强解的存在性仍是一个开放问题,特别是对满足特定相容性条件的充分正则数据,目前仅得到局部存在性结果。本文在二维有界光滑域中重点研究方程的爆破判据,即导致解失去正则性的条件,通过推导独立于密度下界的先验估计,并证明初值问题或初边值问题局部强解的存在性和唯一性,为理解非齐次不可压缩流体动力学中解的稳定性和存在性提供新的理论支持。 展开更多
关键词 非齐次 不可压缩流 NAVIER-stokes方程 爆破判据
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Improvement of a Dual-Polarization Radar Operator for Ice-phase Microphysical Terms
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作者 Ji-Won LEE Ki-Hong MIN GyuWon LEE 《Advances in Atmospheric Sciences》 2026年第3期550-564,共15页
Dual-polarization(dual-pol)radar variables provide information about the quantity,type,size,and water content of hydrometeors.Assimilating these dual-pol radar variables into numerical weather prediction models can en... Dual-polarization(dual-pol)radar variables provide information about the quantity,type,size,and water content of hydrometeors.Assimilating these dual-pol radar variables into numerical weather prediction models can enhance forecast accuracy.Observation operators are essential for radar data assimilation.This study focuses on applying a realistic dual-pol radar observation operator to more accurately calculate dual-pol radar variables.Previously reported dual-pol radar observation operators tended to overestimate radar variables near 0℃ in convective precipitation and simulate unrealistic dual-pol radar variables in subfreezing regions.To address this,the improved operator(KNU dual-pol radar observation operator;K-DROP)limits the distribution of mixed-phase hydrometeors,which have both solid and liquid properties,in areas with strong updrafts and downdrafts,improving the overestimation of radar variables near the melting layer.Additionally,by applying the observed snow axis ratio during winter to K-DROP,the issue of differential reflectivity(Z_(DR))being calculated as a constant value in subfreezing regions has been improved.By incorporating the observed maximum radius of hydrometeors into K-DROP,the overestimation of reflectivity(Z_(H))in subfreezing regions,the overestimation of Z_(DR)in warm regions,and the underestimation of specific differential phase(K_(DP))in subfreezing regions and overestimation in warm regions,are improved.Compared to previous operators,the enhanced version reported in the present work produces more realistic dual-pol radar variables. 展开更多
关键词 dual-polarization radar operator observation operator radar data assimilation remote sensing
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Single broadband source depth estimation using Stokes parameters in shallow water
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作者 Yizheng Wei Chao Sun +1 位作者 Lei Xie Mingyang Li 《Chinese Physics B》 2026年第2期451-460,共10页
Presented in this study is a novel method for estimating the depth of single underwater source in shallow water,utilizing vector sensors.The approach leverages the depth distribution of the broadband Stokes parameters... Presented in this study is a novel method for estimating the depth of single underwater source in shallow water,utilizing vector sensors.The approach leverages the depth distribution of the broadband Stokes parameters to estimate source depth accurately.Unlike traditional matched field processing(MFP)and matched mode processing(MMP),the proposed approach can estimate source depth directly from the data received by sensors without requiring complete environmental information.Firstly,the broadband Stokes parameters(BSP)are established using the normal mode theory.Then the nonstationary phase approximation is used to simplify the theoretical derivation,which is necessary when dealing with broadband integrals.Additionally,range terms of the BSP are eliminated by normalization.By analyzing the depth distribution of the normalized broadband Stokes parameters(NBSP),it is found that the NBSP exhibit extreme values at the source depth,which can be used for source depth estimation.So the proposed depth estimation method is based on searching the peaks of the NBSP.Simulations show that this method is effective in relatively simple shallow water environments.Finally,the effect of source range,frequency bandwidth,sound speed profile(SSP),water depth,and signal-to-noise ratio(SNR)are studied.The findings indicate that the proposed method can accurately estimate the source depth when the SNR is greater than-5 d B and does not need to consider model mismatch issues.Additionally,variations in environmental parameters have minimal impact on estimation accuracy.Compared to MFP,the proposed method requires a higher SNR,but demonstrates superior robustness against fluctuations in environmental parameters. 展开更多
关键词 broadband source depth estimation shallow water POLARIZATION stokes parameters
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A GENERALIZED HILBERT OPERATOR ACTING ON HARDY SPACES
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作者 Huiling CHEN Shanli YE 《Acta Mathematica Scientia》 2026年第1期145-163,共19页
Letα>0 and letμbe a positive Borel measure on the interval[0,1).The Hankel matrix■with entries■induces,formally,the generalized-Hilbert operator■where f(z)■is an analytic function in D.This article is devoted... Letα>0 and letμbe a positive Borel measure on the interval[0,1).The Hankel matrix■with entries■induces,formally,the generalized-Hilbert operator■where f(z)■is an analytic function in D.This article is devoted to study the measuresμfor which Hμ,αis a bounded(resp.,compact)operator from Hp(0<p≤1)into H^(p)(1≤q<∞).We also study the analogous problem in the Hardy spaces H^(p)(1≤p≤2).Finally,we obtain the essential norm of H_(μ,α)from H^(p)(0<p≤1)into H^(p)(1≤q<∞). 展开更多
关键词 Hilbert operator Hardy space Carleson measure essential norm
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Non-Newtonian rivulet flows on an inclined planar surface applying the 2nd Stokes problem
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作者 S.V.ERSHKOV E.S.BARANOVSKII A.V.YUDIN 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期153-164,共12页
The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet ... The newly formulated non-Newtonian rivulet flows streaming down an inclined planar surface,with additional periodic perturbations arising from the application of the 2nd Stokes problem to the investigation of rivulet dynamics,are demonstrated in the current research.Hereby,the 2nd Stokes problem assumes that the surface,with a thin shared layer of the fluid on it,oscillates in a harmonic manner along the x-axis of the rivulet flow,which coincides with the main flow direction streaming down the underlying surface.We obtain the exact extension of the rivulet flow family,clarifying the structure of the pressure field,which fully absorbs the arising perturbation.The profile of the velocity field is assumed to be Gaussian-type with a non-zero level of plasticity.Hence,the absolutely non-Newtonian case of the viscoplastic flow solution,which satisfies the motion and continuity equations,is considered(with particular cases of exact solutions for pressure).The perturbed governing equations of motion for rivulet flows then result in the Riccati-type ordinary differential equation(ODE),describing the dynamics of the coordinate x(t).The approximated schematic dynamics are presented in graphical plots. 展开更多
关键词 rivulet flow non-Newtonian fluid creeping viscoplastic flow 1st/2nd stokes problem
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不可压Navier-Stokes-Poisson-Nernst-Planck方程组大解的整体存在性
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作者 靳荣 赵继红 陈浩 《中山大学学报(自然科学版)(中英文)》 北大核心 2026年第2期144-152,共9页
研究了一类刻画电介质中带电粒子漂移、扩散和对流现象的电流体动力学模型.该模型在数学上表现为椭圆-抛物耦合的拟线性耗散型偏微分方程组,具有强非线性、非局部性和强耦合性等特点.基于对方程组代数结构的细致刻画以及选取恰当的权函... 研究了一类刻画电介质中带电粒子漂移、扩散和对流现象的电流体动力学模型.该模型在数学上表现为椭圆-抛物耦合的拟线性耗散型偏微分方程组,具有强非线性、非局部性和强耦合性等特点.基于对方程组代数结构的细致刻画以及选取恰当的权函数,建立了该方程组在临界Besov空间中具有任意大B_(∞,∞)^(-1)×B_(∞,∞)^(-2)×B_(∞,∞)^(-2)-范数的初值所对应解的整体存在性. 展开更多
关键词 电流体动力学 Navier-stokes-Poisson-Nernst-Planck方程组 大解 整体存在性 BESOV空间
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A Q-Learning Improved Particle Swarm Optimization for Aircraft Pulsating Assembly Line Scheduling Problem Considering Skilled Operator Allocation
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作者 Xiaoyu Wen Haohao Liu +6 位作者 Xinyu Zhang Haoqi Wang Yuyan Zhang Guoyong Ye Hongwen Xing Siren Liu Hao Li 《Computers, Materials & Continua》 2026年第1期1503-1529,共27页
Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in oper... Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in operator workloads and significantly increase the complexity of scheduling.To address this challenge,this study investigates the Aircraft Pulsating Assembly Line Scheduling Problem(APALSP)under skilled operator allocation,with the objective of minimizing assembly completion time.A mathematical model considering skilled operator allocation is developed,and a Q-Learning improved Particle Swarm Optimization algorithm(QLPSO)is proposed.In the algorithm design,a reverse scheduling strategy is adopted to effectively manage large-scale precedence constraints.Moreover,a reverse sequence encoding method is introduced to generate operation sequences,while a time decoding mechanism is employed to determine completion times.The problem is further reformulated as a Markov Decision Process(MDP)with explicitly defined state and action spaces.Within QLPSO,the Q-learning mechanism adaptively adjusts inertia weights and learning factors,thereby achieving a balance between exploration capability and convergence performance.To validate the effectiveness of the proposed approach,extensive computational experiments are conducted on benchmark instances of different scales,including small,medium,large,and ultra-large cases.The results demonstrate that QLPSO consistently delivers stable and high-quality solutions across all scenarios.In ultra-large-scale instances,it improves the best solution by 25.2%compared with the Genetic Algorithm(GA)and enhances the average solution by 16.9%over the Q-learning algorithm,showing clear advantages over the comparative methods.These findings not only confirm the effectiveness of the proposed algorithm but also provide valuable theoretical references and practical guidance for the intelligent scheduling optimization of aircraft pulsating assembly lines. 展开更多
关键词 Aircraft pulsating assembly lines skilled operator reinforcement learning PSO reverse scheduling
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THE BOUNDEDNESS OF INHOMOGENEOUS CALDERÓN-ZYGMUND CONVOLUTION OPERATORS ON LOCAL PRODUCT HARDY SPACES
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作者 Shaoyong HE Jiecheng CHEN 《Acta Mathematica Scientia》 2026年第1期99-111,共13页
It is well known that the inhomogeneous Calderón-Zygmund convolution operators are bounded on the local Hardy spaces.In this paper,we prove that these operators are bounded on the local product Hardy spaces and t... It is well known that the inhomogeneous Calderón-Zygmund convolution operators are bounded on the local Hardy spaces.In this paper,we prove that these operators are bounded on the local product Hardy spaces and the Lipschitz spaces.The key ideas used here are the discrete local Calderón identity and a density argument for the inhomogeneous product Lipschitz spaces in the weak sense. 展开更多
关键词 local Hardy space Lipschitz space inhomogeneous Calderón-Zygmund operator discrete Calderón identity
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时间加权的Besov空间上带外力的分数阶Navier-Stokes方程
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作者 李琳玉 杨和 《西北师范大学学报(自然科学版)》 2026年第1期77-92,共16页
讨论分数阶Navier-Stokes方程在时间加权的Besov空间中mild解的存在性和唯一性.基于Lebesgue控制收敛定理、Banach空间隐函数定理、Besov空间上Navier-Stokes方程的L p-L q估计以及Mittag-Leffler函数的相关性质,给出了具有小初始数据... 讨论分数阶Navier-Stokes方程在时间加权的Besov空间中mild解的存在性和唯一性.基于Lebesgue控制收敛定理、Banach空间隐函数定理、Besov空间上Navier-Stokes方程的L p-L q估计以及Mittag-Leffler函数的相关性质,给出了具有小初始数据和外力的情况下该方程全局mild解的存在性和唯一性定理,并研究了给定数据下局部mild解的存在性. 展开更多
关键词 分数阶Navier-stokes方程 时间加权的Besov空间 MILD解 适定性
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具有Dirichlet信号边界的趋化Navier-Stokes模型的整体适定性
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作者 王晓琪 吴杰 《西北师范大学学报(自然科学版)》 2026年第1期49-58,共10页
研究二维光滑有界区域中具有二次衰减和Dirichlet信号边界的趋化Navier-Stokes模型的整体适定性.为了克服非齐次Dirichlet边界带来的困难,先将原问题转化为齐次Dirichlet边界问题,再利用解的局部存在性理论、能量估计证明了对于满足充... 研究二维光滑有界区域中具有二次衰减和Dirichlet信号边界的趋化Navier-Stokes模型的整体适定性.为了克服非齐次Dirichlet边界带来的困难,先将原问题转化为齐次Dirichlet边界问题,再利用解的局部存在性理论、能量估计证明了对于满足充分正则性的初始条件,该模型都存在一致有界的整体经典解.在某些附加假设下,借助Hölder估计与时空估计分析了解的大时间行为. 展开更多
关键词 趋化Navier-stokes模型 Dirichlet信号边界条件 logistic源项 整体有界性 大时间行为
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微小槽道内向列相液晶Stokes绕流空化实验研究
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作者 于佳佳 蒋璐阳 +2 位作者 黄利 吴春梅 李友荣 《工程热物理学报》 北大核心 2025年第3期890-896,共7页
本文报道了微小槽道内向列相5CB液晶绕流并联钝体水力空化现象。通过实验研究了并联双圆柱钝体对向列相5CB液晶空化特性的影响规律,探索了流动过程中向错环的变化规律。结果表明在并联双圆柱后出现的向错环的长度以及宽度都会随着雷诺... 本文报道了微小槽道内向列相5CB液晶绕流并联钝体水力空化现象。通过实验研究了并联双圆柱钝体对向列相5CB液晶空化特性的影响规律,探索了流动过程中向错环的变化规律。结果表明在并联双圆柱后出现的向错环的长度以及宽度都会随着雷诺数的增大而减小,并且在雷诺数远远小于1,处于Stokes流时,并联双圆柱后能够产生空化现象;并联双圆柱钝体后空化域的振荡行为与单圆柱钝体后空化域的振荡规律类似,斯特劳哈尔数随雷诺数的增大而减小;设置有并联双圆柱和单圆柱的微通道进出口压差与雷诺数均成线性关系。 展开更多
关键词 微小槽道 向列相液晶 水力空化 stokes 并联双圆柱
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Green公式、Gauss公式和Stokes公式的证明
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作者 楼红卫 《大学数学》 2025年第4期1-9,共9页
在数学分析课程中,Green公式、Gauss公式和Stokes公式是曲线曲面积分中最重要的几个定理.但在通常的教材中,给出相关定理时,要么只是考虑了条件非常特殊时的情形,要么省略了证明或对于证明语焉不详.文章试图在数学分析课程通常会关心的... 在数学分析课程中,Green公式、Gauss公式和Stokes公式是曲线曲面积分中最重要的几个定理.但在通常的教材中,给出相关定理时,要么只是考虑了条件非常特殊时的情形,要么省略了证明或对于证明语焉不详.文章试图在数学分析课程通常会关心的条件下,诸如曲线或曲面是分片连续可微且可定向的条件下,来给出相关定理的严谨而完整的证明. 展开更多
关键词 Green公式 GAUSS公式 stokes公式
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