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91.
We construct the generalized version of covariant Z3-graded differential calculus introduced by one of us (R.K.) and then extend it to the case of arbitrary ZN grading. Here our main purpose is to establish the recurrence formulae for the Nth power of covariant q-differential Dq=dq + A and to analyze more closely the particular case of q being an Nth primitive root of unity. The generalized notions of connection and curvature are introduced and several examples of realization are displayed for N=3 and 4. Finally we briefly discuss the idea of infinitesimal deformations of the parameter q in the complex plane. 相似文献
92.
E. V. Korobko Prof. V. E. Dreval Z. P. Shulman V. G. Kulichikhin 《Rheologica Acta》1994,33(2):117-124
Studies have been made of concentrated (up to 60%) diatomite suspensions in transformer oil, the structure and theological properties of which depend on an applied electric field. Studies have been conducted of steady-state and transient regimes of straining involving continuous and periodic shear. The structure in such suspensions is formed in the presence of an electric field of 10–3 –102 duration. The suspensions under continuous stationary strain behave as non-Newtonian fluids with a yield stress dependent on electric intensity. Under periodic deformation conditions the test suspensions exhibit elasticity which abruptly diminishes with increasing deformation amplitude. 相似文献
93.
Experimental data for simple tension suggest that there is a power–law kinematic relationship between the stretches for large
classes of slightly compressible (or almost incompressible) non-linearly elastic materials that are homogeneous and isotropic.
Here we confine attention to a particular constitutive model for such materials that is of generalized Varga type. The corresponding
incompressible model has been shown to be particularly tractable analytically. We examine the response of the slightly compressible material
to some nonhomogeneous deformations and compare the results with those for the corresponding incompressible model. Thus the effects of slight compressibility
for some basic nonhomogeneous deformations are explicitly assessed. The results are fundamental to the analytical modeling
of almost incompressible hyperelastic materials and are of importance in the context of finite element methods where slight
compressibility is usually introduced to avoid element locking due to the incompressibility constraint. It is also shown that
even for slightly compressible materials, the volume change can be significant in certain situations.
相似文献
94.
We give a complete classification of at most second-order differential ladder operators preserving finite-dimensional spaces of monomials and closing under the Lie bracket to give a cubic polynomial of the diagonal generators. 相似文献
95.
J. Gizon B. M. Nyak J. Timr A. Gizon L. Zolnai A. J. Boston Gh.Cata-Danil J. Genevey D. T. Joss N. J. O'Brien C. M. Parry E. S. Paul D. Santos A. T. Semple A. V. Afanasjev I. Ragnarsson 《Physics letters. [Part B]》1997,410(2-4):95-102
The level structure of 102Pd has been investigated using data collected with the Eurogam 2 array. Several cascades of γ-rays have been established up to high spins. Termination of rotational bands has been observed at Iπ = 28− and 32+, and tentatively at Iπ = 38+ and 42+. The nucleus 102Pd is the first case where rotational bands built on valence space configurations are followed from spin close to zero up to termination and, at higher spins, a smooth rotational band which appears to terminate is built on core excited configurations. 相似文献
96.
Differential conditions are derived for a smooth deformation to be universal for a class of isotropic hyperelastic materials
that we regard as a compressible variant (a notion we make precise) of Mooney–Rivlin’s class, and that includes the materials studied originally by Tolotti in 1943
and later, independently, by Blatz. The collection of all universal deformations for an incompressible material class is shown
to contain, modulo a uniform dilation, all the universal deformations for its compressible variants. As an application of this result, by searching
the known families of universal deformations for all incompressible isotropic materials, a nontrivial universal deformation
for Tolotti materials is found.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
97.
We consider a family of deformations describing cylindrical inflations within the context of finite, compressible, isotropic
elasticity. We pose the problem of finding the maximal class of materials for which these deformations are possible at equilibrium
under surface tractions only. We solve this problem for families of cylindrical inflations whose principal strain invariants
have a special dependence on the radius. These families comprise and extend all cases considered by Murphy [2].
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
98.
M. M. Carroll 《Journal of Elasticity》2007,88(2):141-149
In an earlier paper, the broadest classes of compressible isotropic strain energies that support irrotational universal deformations
were identified and the problems of cylindrical and spherical inflation or compaction were solved in closed form for all of
these strain energies. Similar closed form solutions of the problem of azimuthal shear are presented here.
相似文献
99.
Let (M,F) be a symplectic manifold and consider a Lie subalgebra of its Lie algebra of symplectic vector fields. We prove that every one-differentiable deformation of order k of the Poisson Lie algebra of M, which is invariant with respect to , extends to an invariant one-differentiable deformation of infinite order. If M admits a -invariant linear connection, a similar result holds true for differentiable deformations and for star-products. In particular, if M admits a - -invariant linear connection, there always exists a -invariant star-product. 相似文献
100.
Zdeněk Fiala 《Comptes Rendus Mecanique》2004,332(2):97-102
The infinite dimensional Riemannian geometry of Riemannian metrics is employed to propose novel objective time derivative by means of covariant derivative. To cite this article: Z. Fiala, C. R. Mecanique 332 (2004). 相似文献