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311.
Ming Chun XU 《数学学报(英文版)》2005,21(4):899-902
In this paper the following theorem is proved: Every group L3(q) for q = 3^(2m-1)(m≥2) is characterized by its set of element orders. 相似文献
312.
刘立山 《应用数学和力学(英文版)》1993,14(7):685-692
In this paper,using some conditions of(sub)compatibility between a set-valuedmapping and a single-valued mapping,we establish a necessary and sufficientcondition and a sufficient condition for set-valued generalized nonexpansive mappingsto have a unique common fixed point in complete convex metric spaces.The resultsimprove,extend and develop the main results in[2-7]. 相似文献
313.
本文提出并论证了粘性正压流体流动的混合协调有限元变分原理,在论证中发现应力协调条件会自然满足。同时提出论证了有关的混合杂交非协调有限元广义变分原理,这能够简化粘性流动的非协调元计算。 相似文献
314.
虚阶Bessel函数的计算 总被引:3,自引:0,他引:3
给出了计算虚阶Bessel函数及其导数的完整算法。数值结果表明,计算精度可达10位以上有效数字。此外,所给出的逆推法可推广到复阶数的情形。 相似文献
315.
A simplified kinematic procedure at a cell level is proposed to obtain in-plane elastic moduli and macroscopic masonry strength domains in the case of herringbone masonry. The model is constituted by two central bricks interacting with their neighbors by means of either elastic or rigid-plastic interfaces with friction, representing mortar joints. The herringbone pattern is geometrically described and the internal law of composition of the periodic cell is defined.A sub-class of possible elementary deformations is a-priori chosen to describe joints cracking under in-plane loads. Suitable internal macroscopic actions are applied on the Representative Element of Volume (REV) and the power expended within the 3D bricks assemblage is equated to that expended in the macroscopic 2D Cauchy continuum. The elastic and limit analysis problem at a cell level are solved by means of a quadratic and linear programming approach, respectively.To assess elastic results, a standard FEM homogenization is also performed and a sensitivity analysis regarding two different orientations of the pattern, the thickness of the mortar joints and the ratio between block and mortar Young moduli is conducted. In this way, the reliability of the numerical model is critically evaluated under service loads.When dealing with the limit analysis approach, several computations are performed investigating the role played by (1) the direction of the load with respect to herringbone bond orientation, (2) masonry texture and (3) mechanical properties adopted for joints.At a structural level, a FE homogenized limit analysis is performed on a masonry dome built in herringbone bond. In order to assess limit analysis results, additional non-linear FE analyses are performed, including a full 3D numerical expensive heterogeneous approach and models where masonry is substituted with an equivalent macroscopic material with orthotropic behavior and possible softening. Reliable predictions of collapse loads and failure mechanisms are obtained, meaning that the approach proposed may be used by practitioners for a fast evaluation of the effectiveness of herringbone bond orientation. 相似文献
316.
A Lagrangian compatible radiation hydrodynamic algorithm and the nuclear dynamics computing module are developed and implemented in the LARED Integration code, which is a radiation hydrodynamic code based on the 2-D cylindrical coordinates for the numerical simulation of the indirect-drive Inertial Confined Fusion. A number of 1-D and 2-D ignition implosion numerical simulations by using the improved LARED Integration code (ILARED) are presented which show that the 1-D numerical results are consistent with those computed by the 1-D radiation hydrodynamic code RDMG, while the simulation results of the 2-D low-mode radiative asymmetry and hydrodynamic instability growth,according to the physical analysis and anticipation, are satisfactory. The capsules driven by the sources from SGII experiments are also simulated by ILARED, and the fuel shapes agree well with the experimental results. The numerical simulations demonstrate that ILARED can be used in the simulation of the 1-D and 2-D ignition capsule implosion using the multi-group diffusion model for radiation. 相似文献
317.
企业战略联盟作为一种新型、双赢的商业竞争模式,近年来,其联盟的形成问题一直是学术界与应用领域广泛关注的研究内容。本文在分析影响企业战略联盟形成的各因素基础上,首先利用序关系G1法对各影响因素指标进行了权重确定,并用基于相似度的聚类分析法来对属性权重进行筛选和修正;其次以形成的联盟稳定性最高为目标,以λ-最大相容类模拟联盟中各企业之间的相似关系,利用粗糙规划模型的性质和特点,建立了基于λ-最大相容类的粗糙规划模型;最后结合企业战略联盟的具体实例,分析了该模型的特点和有效性。结果表明,该模型丰富了现有的理论成果,为战略联盟的有效形成提供了正确的决策参考。 相似文献
318.
319.