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991.
The linear equivalence method (LEM), introduced by [Bull. Math. Soc. Sci. Math. de la Roumanie 24 (72) (1980) 4417; An. Univ. Bucure
ti, ser. Matematica 31 (1982) 75] to get solutions of nonlinear ODEs, was used so far to get differential type representations. New LEM representations of integral type are presented here and used for the study of the nonlinear elastic bar; a good approximating formula for the rotation of the cross-section at the bar end is also obtained, in case of a simply supported bar. A parallel old–new results is made by means of a programming code. 相似文献
992.
Based on the lattice Boltzmann method (LBM), the sedimentations of a single elastic dumbbell in a Newtonian fluid under different initial positions and orientations, and also that of the elastic dumbbells with different free lengths of the spring under the same initial conditions have been simulated. All of the numerical results show that the final orientations of the elastic dumbbells are in the same horizontal direction, and the final positions of their centroids are all on the centerline of the tube no matter what the initial positions and orientations of the elastic dumbbell or the free lengths of the spring are. When the elastic dumbbell finally falls down vertically, the two circular cylinders of the elastic dumbbell rotate around their own symmetry-axis respectively, and their angular velocities are equal but opposite to each other. For the sedimentations of the elastic dumbbells with different free lengths of the spring, the shorter of the free length is, the faster the final angular velocity and vertical velocity of the circular cylinder will be. 相似文献
993.
994.
Vladimir Marianov 《Annals of Operations Research》2003,123(1-4):125-141
We formulate a model for locating multiple-server, congestible facilities. Locations of these facilities maximize total expected demand attended over the region. The effective demand at each node is elastic to the travel time to the facility, and to the congestion at that facility. The facilities to be located are fixed, so customers travel to them in order to receive service or goods, and the demand curves at each demand node (which depend on the travel time and the queue length at the facility), are known. We propose a heuristic for the resulting integer, nonlinear formulation, and provide computational experience. 相似文献
995.
Properties of Epoxy Systems with Clay Nanocomposites 总被引:4,自引:0,他引:4
Zelenkova Myskova M. Zelenka J. Spacek V. Socha F. 《Mechanics of Composite Materials》2003,39(2):119-122
Different types of montmorillonite clays are often used for the modification of thermoplastic polymers. In the case of epoxy systems, the presence of the clays can complicate the cure process. Therefore, the influence of montmorillonite concentration and the temperature regime on the cure rate and mechanical properties of the composite material obtained is investigated in this paper. 相似文献
996.
The method of optical model analysis of generalized elastic scattering angular distributions (GESA) has been applied to heavy
ion scattering to derive fusion spin distributions. This method is used to reproduce the coupled channel fusion spin distributions.
When applied to experimental data, particularly to the fissile systems like16O +232Th, the method gives large mean square spin values in agreement with “anomalous” values derived from experimental fission
fragment anisotropies. 相似文献
997.
Fosdick and Kao [1] extended a conjecture of Ericksen's [2] for non-linear fluids, to non-linear elastic solids, and showed
that unless the material moduli of an isotropic elastic material satisfied certain special relations, axial shearing of cylinders
would be necessarily accompanied by secondary deformations if the cross-section were not a circle or the annular region between
two concentric circles. Further, they used the driving force as the small parameter for a perturbation analysis and showed
that the secondary deformation will occur at fourth order, much in common with what is known for non-linear fluids. Here,
we show that if on the other hand the driving force is not small (of O(1)), but the departure of the cylinder from circular
symmetry is small, then secondary deformations appear at first order, the parameter for perturbance being the divergence from
circular symmetry.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
998.
We derive a weighted and anisotropic Korn inequality for a system of elastic thin rods and verify its asymptotic accuracy. The structure of the norms at the construction elements (rods and knots) is determined from classifying the elements and assigning them to the following categories: movable, hard-movable, and clamped. This classification was never involved while the constraints on the structure of systems of rods in the preceding reserach excluded the presence of movable elements. 相似文献
999.
王惠平 《宁波大学学报(理工版)》2002,15(1):73-74
分析了《建筑地基基础规范》《建筑桩基技术规范》所确定的桩基承载力计算公式和参数影响。通过工程实例的对比分析,得到了两个承载力的差异程度,并对桩基规范的基础设计提出了建议的简化设计方法。 相似文献
1000.
粘弹性半空间上刚体的垂直振动 总被引:1,自引:0,他引:1
根据弹性力学混合边值条件,建立了粘弹性半空间上刚体垂直振动的对偶积分方程,并用正交多项式化积分方程为线性代数方程组,并提出可以用围线积分和解析开拓原理把方程组系数的无穷积分化为有穷积分。计算结果与实测资料进行了比较,说明本方法是正确的。 相似文献