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481.
有效消减样品端面摩擦力是保证分离式霍普金森压杆(split Hopkinson pressure bar, SHPB)实验结果有效性和准确性的必要条件。为了研究样品粗糙度和润滑效果对端面摩擦力和最终实验结果的影响,以应变率效应不敏感且性能稳定的紫铜为研究对象,通过机械加工配合酸蚀的方法制备了3种典型表面粗糙度的紫铜样品,分别在二硫化钼(MoS2)充分润滑和完全不润滑的条件下各自开展高精度的SHPB重复动态压缩实验研究。结果表明,通常认为能够有效消减金属样品端面摩擦力的MoS2仅能够在样品粗糙度不大于0.8 μm的情况下起到较好的润滑效果,随着紫铜样品粗糙度的增加,MoS2的润滑效果不断降低,端面摩擦力不断增大,实验结果的分散性也显著增加。样品端面粗糙度为1.6 μm时,MoS2已不能有效消减端面摩擦力;样品端面粗糙度达到3.2 μm时,MoS2的润滑效果几乎为零。SHPB实验中使用MoS2润滑金属样品时,压杆和样品实验端面的粗糙度需达到0.8 μm;腐蚀液处理后的金属样品外表面粗糙度难以达到0.8 μm,实验过程中需对样品端面进行比MoS2润滑效果更好的润滑处理,或对实验结果进行扣除端面摩擦力的修正才能够保证实验结果的有效性和准确性。 相似文献
482.
Yekini Shehu 《Numerical Functional Analysis & Optimization》2016,37(8):1021-1036
The purpose of this article is to study the iterative approximation of solution to multiple sets split feasibility problems in p-uniformly convex real Banach spaces that are also uniformly smooth. We propose an iterative algorithm for solving multiple sets split feasibility problems and prove a strong convergence theorem of the sequence generated by our algorithm under some appropriate conditions in p-uniformly convex real Banach spaces that are also uniformly smooth. 相似文献
483.
We define the A4‐structure of a graph G to be the 4‐uniform hypergraph on the vertex set of G whose edges are the vertex subsets inducing 2K2, C4, or P4. We show that perfection of a graph is determined by its A4‐structure. We relate the A4‐structure to the canonical decomposition of a graph as defined by Tyshkevich [Discrete Math 220 (2000) 201–238]; for example, a graph is indecomposable if and only if its A4‐structure is connected. We also characterize the graphs having the same A4‐structure as a split graph. 相似文献
484.
图的spread定义为图的邻接矩阵的最大特征值与最小特征值的差.本文确定了n(n≥84)顶点四圈图中spread最大的唯一的图. 相似文献
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In this paper,the half-strong,the locally strong and the quasi-strong endomorphisms of a split graph are investigated.Let X be a split graph and let End(X),hEnd(X),lEnd(X) and qEnd(X) be the endomorphism monoid,the set of all half-strong endomorphisms,the set of all locally strong endomorphisms and the set of all quasi-strong endomorphisms of X,respectively.The conditions under which hEnd(X) forms a submonoid of End(X) are given.It is shown that lEnd(X) = qEnd(X) for any split graph X.The conditions under which lEnd(X)(resp.qEnd(X)) forms a submonoid of End(X) are also given.In particular,if hEnd(X) forms a monoid,then lEnd(X)(resp.qEnd(X)) forms a monoid too. 相似文献
487.
Omar Belhamiti 《Communications in Nonlinear Science & Numerical Simulation》2012,17(2):555-565
In this paper, we propose a new approach based on conjunction of the orthogonal collocation on finite elements method with decoupling and quasi-linearization technique to approximate solutions of a set of nonlinear split boundary value problems. The numerical stability, the convergence and the accuracy of the results are checked by this algorithm. The approach developed in this study is illustrated by some numerical examples. These examples are solved using a special software package which implements the proposed algorithms. 相似文献
488.
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490.
Solomon Bekele Zegeye Habtu Zegeye Mengstu Goa Sangago Oganeditse A. Boikanyo Sebsibe Teferi Woldeamanuel 《Mathematical Methods in the Applied Sciences》2023,46(2):2884-2905
In this paper, we propose an inertial algorithm for solving split equality of monotone inclusion and -fixed point of Bregman relatively -nonexpansive mapping problems in reflexive real Banach spaces. Using the Bregman distance function, we prove a strong convergence theorem for the algorithm produced by the method in real reflexive Banach spaces. In addition, we provide some applications of our method and give numerical results to demonstrate the applicability and efficiency of the proposed method. 相似文献