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81.
Impact Responses of Prismatic Lithium-Ion Battery Based on the Membrane Factor Method北大核心CSCD
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Aimed at the internal short circuit problem due to large deformation of the prismatic lithium-ion battery cell under impact loadings, a simplified battery model was first established. Then the motion equations of velocity and displacement based on the membrane factor method were proposed. With the effects of the face-sheet thickness and the densification region on the normalized final deflection, impact response characteristics of prismatic battery cells were investigated in detail. The results show that, the improved motion equations involving the membrane factor can reflect the dynamic response mechanisms of the prismatic battery cell under impact loadings, and the large deflection under high-speed impact can be predicted. With the increase of the face-sheet thickness, the deflection of the battery cell’s lower part decreases obviously. However, the densification region expands with the face-sheet thickness. The deflection and the densification region of the cell’s lower part both increase with the inner core density of the battery. This proposed impact model provides a theoretical guidance for the multi-functional integrated dynamic design of prismatic battery cells. © 2022 Editorial Office of Applied Mathematics and Mechanics. All rights reserved. 相似文献
82.
The Regularity of Stochastic Convolution Driven by Tempered Fractional Brownian Motion and Its Application to Mean-field Stochastic Differential Equations
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In this paper, some properties of a stochastic convolution driven by tempered fractional Brownian motion are obtained. Based on this result, we get the existence and uniqueness of stochastic mean-field equation driven by tempered fractional Brownian motion. Furthermore, combining with the Banach fixed point theorem and the properties of Mittag-Leffler functions, we study the existence and uniqueness of mild solution for a kind of time fractional mean-field stochastic differential equation driven by tempered fractional Brownian motion. 相似文献
83.
It is known that at the critical temperature the Curie-Weiss mean-field model has non-Gaussian fluctuations and that internal fluctuations can be Gaussian. Here we compute the distribution of theq-mode magnetization fluctuations as a function of the temperature, the wave vectorq, and a fading out external field. We obtain new classes of probability distributions generated by this external field as well as new critical behavior in terms of its rate of fading out. We discuss also the susceptibility as the limitq tending to zero. 相似文献
84.
We consider the covariance matrix,G
mm
=q
2<(x,m);(y,m)>, of thed-dimensionalq-states Potts model, rewriting it in the random cluster representation of Fortuin and Kasteleyn. In any of theq ordered phases, we identify the eigenvalues of this matrix both in terms of representations of the unbroken symmetry group of the model and in terms of random cluster connectivities and covariances, thereby attributing algebraic significance to these stochastic geometric quantities. We also show that the correlation length corresponding to the decay rate of one of the eigenvalues is the same as the inverse decay rate of the diameter of finite clusers. For dimensiond=2, we show that this correlation length and the correlation length of the two-point function with free boundary conditions at the corresponding dual temperature are equal up to a factor of two. For systems with first-order transitions, this relation helps to resolve certain inconsistencies between recent exact and numerical work on correlation lengths at the self-dual point o. For systems with second order transitions, this relation implies the equality of the correlation length exponents from above and below threshold, as well as an amplitude ratio of two. In the course of proving the above results, we establish several properties of independent interest, including left continuity of the inverse correlation length with free boundary conditions and upper semicontinuity of the decay rate for finite clusters in all dimensions, and left continuity of the two-dimensional free boundary condition percolation probability at o. We also introduce DLR equations for the random cluster model and use them to establish ergodicity of the free measure. In order to prove these results, we introduce a new class of events which we call decoupling events and two inequalities for these events. The first is similar to the FKG inequality, but holds for events which are neither increasing nor decreasing; the second is similar to the van den Berg-Kesten inequality in standard percolation. Both inequalities hold for an arbitrary FKG measure. 相似文献
85.
Andrea Posilicano 《Potential Analysis》1996,5(3):241-271
We prove a convergence theorem for sequences of Diffusion Processes corresponding to Dirichlet Forms of the kind
.We obtain convergence in total variation norm of the corresponding probability measures on the path space C(+;d) under hypotheses which, for example, are satisfied in the case of H
loc
1
(
d
)-convergence of the 's, but we can allow more singular situations as regards the approximating sequences. We use then these results to give a criterion of convergence for generalized Schrödinger operators in which the potential function should not necessarily exists as a measurable function. We obtain convergence not only in strong resolvent sense, but we also obtain convergence in the uniform operator topology up to sets of arbitrarily small Lebesgue measure. Applications to the problem of the approximation of ordinary Schrödinger operators by generalized ones corresponding to zero-range interactions are given. 相似文献
86.
Juha Vuolle-Apiala 《Journal of Theoretical Probability》1996,9(4):853-861
We consider a class of possible extensions of a given symmetric Feller processZ
t
fromR{0} to the entire real lineR, depending on a parameter [0, 1]. It is proved that the proposed extension exists if =1/2; for 1/2, exists if and only ifZ
t
does not jump over 0 (e.g., ifZ
t
is a diffusion). 相似文献
87.
LetX be a Brownian motion defined on the line (withX(0)=0) and letY be an independent Brownian motion defined on the nonnegative real numbers. For allt0, we define theiterated Brownian motion (IBM),Z, by setting
. In this paper we determine the exact uniform modulus of continuity of the process Z.Research supported by NSF grant DMS-9122242. 相似文献
88.
Laurent Serlet 《Journal of Theoretical Probability》1996,9(3):561-578
We study super-Brownian motion inR
d
starting from a nontrivial finite measure and conditioned to nonextinction as defined by Evans. If (Y
t
)
t0
denotes this process, we provide a new approach to the immortal particle representation of (Y
t
)
t0
. We then show that the measureZ onR
d
defined byZ(B)=
o
1
Y
t
(B) dt is almost surely finite on compact sets whend5 and almost surely infinite on every ball whend4. 相似文献
89.
半晶性的聚对苯二甲酸乙二醇酯(PET)存在不同尺寸运动单元的多重形式的分子运动,而且PET等高聚物前结构欠序、晶界和杂质等缺陷还使电子价带与导带间的禁带中出现局域能级(陷阱),并成为捕获载流子的中心,从而影响载流子的输运性质。分子运动和陷阱 相似文献
90.
本文研究了 PVDF-P(VDF-HFE)以及 PVDF-P(VDF-TFE)共混体系的压电、介电、力学松弛谱。其松弛转变过程基本与 PVDF 的相似。α,β,γ压电松弛峰分别位于40~120℃,-40℃,-85℃附近。实验结果表明后一体系的压电性大于前一体系的。同时,PVDF-P(VDF-TFE)的压电性也大于PVDF-PMMA 共混体系的。选择第二组分时,以介电常数高,模量小而本身又具有压电性的,更有助于共混薄膜压电性的提高。在同样的极化条件下,经拉伸的 P(VDF-TFE)薄膜,其压电性大于未经拉伸的薄膜,这表明分子的取向对薄膜的压电性也有影响。TSC 表明,42℃的松弛峰与晶区表面捕获的空间电荷有关,对压电性也有一定的贡献。 相似文献