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81.
82.
Charles R. Johnson 《Discrete Mathematics》2006,306(23):3130-3135
Among those real symmetric matrices whose graph is a given tree T, the maximum multiplicity is known to be the path cover number of T. An explicit characterization is given for those trees for which whenever the maximum multiplicity is attained, all other multiplicities are 1. 相似文献
83.
本文针对复杂杆系结构提出一种超级有限条的分析方法。这种方法基于半连续半离散思想将各杆件结点自由度归结为整体结构自由度;进一步又将整体自由度简化为少数结线自由度上机计算。这将为复杂结构体系开拓一条简便、实用的工程分析途径。 相似文献
84.
A new model shift mapping was given in bilateral symbol space. It is topologically conjugate with the traditional shift mapping. Similar to Smale Horseshoe, a model was constructed correspondent to the model shift mapping, i.e., a class of mapping on Mbius strip was given. Its attractors’ structure and dynamical behaviour were described. 相似文献
85.
X.-F. Li 《Archive of Applied Mechanics (Ingenieur Archiv)》2003,72(10):745-758
Summary The dynamic problem of an impermeable crack of constant length 2a propagating along a piezoelectric ceramic strip is considered under the action of uniform anti-plane shear stress and uniform
electric field. The integral transform technique is employed to reduce the mixed-boundary-value problem to a singular integral
equation. For the case of a crack moving in the mid-plane, explicit analytic expressions for the electroelastic field and
the field intensity factors are obtained, while for an eccentric crack moving along a piezoelectric strip, numerical results
are determined via the Lobatto–Chebyshev collocation method for solving a resulting singular integral equation. The results
reveal that the electric-displacement intensity factor is independent of the crack velocity, while other field intensity factors
depend on the crack velocity when referred to the moving coordinate system. If the crack velocity vanishes, the present results
reduce to those for a stationary crack in a piezoelectric strip. In contrast to the results for a stationary crack, applied
stress gives rise to a singular electric field and applied electric field results in a singular stress for a moving crack
in a piezoelectric strip.
Received 14 August 2001; accepted for publication 24 September 2002
The author is indebted to the AAM Reviewers for their helpful suggestions for improving this paper. The work was supported
by the National Natural Science Foundation of China under Grant 70272043. 相似文献
86.
Coiled strip can be directly produced through the twin-roll strip casting process from the melt by incorporating casting and hot rolling together into a single step. In this unique process, the strip formation from the molten metal critically relies upon the casting rolls. Thus, the design of the rolls is extremely essential. The coupled heat transfer and deformation analysis of the casting roll is carried out in a two-dimensional numerical model, using a finite element program (MARC) to examine the thermal stress and displacement. The effects of several factors such as the nickel overlay thickness on the roll surface, the casting speed, and the roll diameter on thermal characteristics are investigated. 相似文献
87.
Periodic vibro-impacts and their stability of a dual component system 总被引:11,自引:0,他引:11
The coexisting periodic impacting motions and their multiplicity of a kind of dual component systems under harmonic excitation
are analytically derived. The stability condition of a periodic impacting motion is given by analyzing the propagation of
small, arbitrary perturbation from that motion. In numerical simulations, the periodic impacting motions are classified according
to the system states before and after an impact. The numerical results show that there exist many types of vibro-impacts and
the bifurcation of periodic vibro-impacts is not smooth.
Project supported in part by National Natural Science Foundation of China under the grant 59572024 and in part by Trans-century
Training Program Foundation for the Talents by the State Education Commission of China 相似文献
88.
Tomohiro Okuma 《Mathematische Nachrichten》2015,288(2-3):343-352
From a resolution graph with certain conditions, Neumann and Wahl constructed an equisingular family of surface singularities called splice quotients. For this class some fundamental analytic invariants have been computed from their resolution graph. In this paper we give a method to compute the multiplicity of an abelian covering of a splice quotient from its resolution graph and the Galois group. 相似文献
89.
Kuo-Chih Hung 《Journal of Mathematical Analysis and Applications》2011,375(1):294-309
We study bifurcation diagrams of positive solutions for the p-Laplacian Dirichlet problem
90.
Yong-ping Sun 《高校应用数学学报(英文版)》2011,26(3):253-264