negative geotropism

By means of a new iteration method,the existence of a backward solution of Boltzmann equation is proved,with initial data close to a local Maxwell in the case of hard potentials with angular cut-off and with infinite mass and energy.

在初值能量无限以及碰撞核为Maxwell分子模型的情况下,采用一种新的迭代方法,证明了Boltzmann方程负向解的存在性。

For the behavior of structure fracture,the dissipation of energy and the damage of passive encourage should be taken into consideration in the course of dynamic damage.

焊接钢桥结构持续损伤至破坏的过程可以从两方面加以分析:一方面要考虑此过程中能量的耗散;另一方面要考虑此过程中焊接部位损伤负向激励。