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排序方式: 共有9883条查询结果,搜索用时 15 毫秒
51.
This paper presents an operator‐splitting method (OSM) for the solution of the universal Reynolds equation. Jakobsson–Floberg–Olsson (JFO) pressure conditions are used to study cavitation in liquid‐lubricated journal bearings. The shear flow component of the oil film is first solved by a modified upwind finite difference method. The solution of the pressure gradient flow component is computed by the Galerkin finite element method. Present OSM solutions for slider bearings are in good agreement with available analytical and experimental results. OSM is then applied to herringbone grooved journal bearings. The film pressure, cavitation areas, load capacity and attitude angle are obtained with JFO pressure conditions. The calculated load capacities are in agreement with available experimental data. However, a detailed comparison of the present results with those predicted using Reynolds pressure conditions shows some differences. The numerical results showed that the load capacity and the critical mass of the journal (linear stability indicator) are higher and the attitude angle is lower than those predicted by Reynolds pressure conditions for cases of high eccentricities. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
52.
Andrade Doherty 《偏微分方程(英文版)》1999,12(4):337-344
In this work we are concerned with the existence of integral solution for a nonlinear abstract viscoelastic problem in Banach space, where the operator is accretive dependent on time. 相似文献
53.
Yuqin Liu & Xing Fu 《数学研究》2022,55(2):109-123
In this paper, we establish the boundedness of the bilinear fractional integral operator $B_alpha$ and the subbilinear fractional maximal operator $M_alpha$ on vanishing generalized Morrey spaces $V_{0}L^{p,varphi}(mathbb{R}^n)$, $V_{infty}L^{p,varphi}(mathbb{R}^n)$ and $V^{(*)}L^{p,varphi}(mathbb{R}^n)$. The main novelty of this article is that we control $B_{alpha}$ by the subbilinear maximal operator $M$ and $M_{alpha'}$ with $alpha'>alpha$. Some specific examples for the main results of this paper are also included. 相似文献
54.
Hacer Bilgin Ellidokuzoğlu & Serkan Demiriz 《分析论及其应用》2021,37(4):557-571
Başar and Braha [1], introduced the sequence spaces $\breve{\ell}_\infty$, $\breve{c}$ and $\breve{c}_0$ of Euler-Cesáro bounded, convergent and null difference sequences and studied their some properties. Then, in [2], we introduced the sequence spaces ${[\ell_\infty]}_{e.r}, {[c]}_{e.r}$ and ${[c_0]}_{e.r}$ of Euler-Riesz bounded, convergent and null difference sequences by using the composition of the Euler mean $E_1$ and Riesz mean $R_q$ with backward difference operator $\Delta$. The main purpose of this study is to introduce the sequence space ${[\ell_p]}_{e.r}$ of Euler-Riesz $p-$absolutely convergent series, where $1 \leq p <\infty$, difference sequences by using the composition of the Euler mean $E_1$ and Riesz mean $R_q$ with backward difference operator $\Delta$. Furthermore, the inclusion $\ell_p\subset{[\ell_p]}_{e.r}$ hold, the basis of the sequence space ${[\ell_p]}_{e.r}$ is constructed and $\alpha-$, $\beta-$ and $\gamma-$duals of the space are determined. Finally, the classes of matrix transformations from the ${[\ell_p]}_{e.r}$ Euler-Riesz difference sequence space to the spaces $\ell_\infty, c$ and $c_0$ are characterized. We devote the final section of the paper to examine some geometric properties of the space ${[\ell_p]}_{e.r}$. 相似文献
55.
Qiulan Qi & Juan Liu 《数学研究通讯:英文版》2012,28(1):1-9
In this paper we give a strong converse inequality of type B in terms of
unified $K$-functional $K^α_λ (f, t^2) (0 ≤ λ ≤ 1, 0 < α < 2)$ for the Meyer-König and
Zeller-Durrmeyer type operators. 相似文献
56.
Yan Wu & Xianmin Xu 《数学研究通讯:英文版》2009,25(1):19-29
In this paper, we prove that the Toeplitz operator with finite Blaschke
product symbol $S_{ψ(z)}$ on $N_ϕ$ has at least $m$ non-trivial minimal reducing subspaces,
where $m$ is the dimension of $H^2(Γ_ω) ⊖ ϕ(ω)H^2
(Γ_ω)$. Moreover, the restriction
of $S_{ψ(z)}$ on any of these minimal reducing subspaces is unitary equivalent to the
Bergman shift $M_z$. 相似文献
57.
REPRESENTATION OF GENERALIZED TRANSLATIONS OF THE PRODUCT OF TWO FUNCTIONS ON SIGNED HYPERGROUPS ON THE REAL LINE
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In this paper,we consider the generalized translations associated with the Dunkl and the Jacobi-Dunkl differential-difference operators on the real line which provide the structure of signed hrpergroups on R.Especially,we study the representation of the generalized translations of the product of two functions for these signed hypergroups. 相似文献
58.
Qinwu Xu & Zhoushun Zheng 《数学研究》2014,47(2):173-189
In this paper, we propose a finite difference/collocation method for two-dimensional time fractional diffusion equation with generalized fractional operator. The main purpose of this paper is to design a high order numerical scheme for the new generalized time fractional diffusion equation. First, a finite difference approximation formula is derived for the generalized time fractional derivative, which is verified with order $2-alpha$ $(0相似文献
59.
利用外张量场下的QCD求和规则计算了核子张量荷,其中核子插入场的核子流算符取最一般形式或称为非常规型,计算包括至维度8的项的贡献.详细分析了不同核子插入场及张量磁化率对计算核子张量荷求和规则的影响.计算表明,改变核子插入场及张量磁化率仍不能得到求和规则的稳定解,但如取最佳插入场的形式,对同位旋矢量和同位旋标量的求和规则解的稳定性有所改善.给出了在通常的对核子“QCD求和规则窗口”标度下核子张量荷的平均值. 相似文献
60.