应力

Virial stress and engineering stress are calculated by two nano-scale stress calculation methods.

纳米尺度的应力计算方法包括维里应力和工程应力的计算方法。

Based on the unloading stress-strain relationship obtained from the unloading stress path experiment reflecting the stress-strain characters of soil in the active area behind the wall, the relationship between the friction angle and wall movement is established under nonlimit state.

根据反映墙后主动区土体应力-应变性状的卸荷应力路径试验确定的应力-应变关系，建立非极限状态摩擦角与墙体位移的关系。

Test results are as follows: Ballastless track structures can effectively improve the dynamic action of train loads on subgrade beds, the measured stresses and acceleration rates are far smaller than those measured with ballasted track structures; axle loads have remarkable influence on dynamic stresses of ballastless track subgrades and have some influence on acceleration responses; speeds of either motor car units or freight trains all have limited effect on dynamic embankment responses; after attenuating over 3 meters high embankment, neither dynamic stresses nor acceleration rates are influential to net cushions at the bottom of column-net structure subgrades

结果表明：采用无砟轨道结构可以有效改善列车荷载对路基基床的动力作用，测得的动应力与加速度值均远小于有砟轨道结构测得的值；列车轴重对无砟轨道路基的动应力影响明显，对加速度响应也有一定影响；无论是动车组还是货物列车，其运行速度对路堤部分的动响应影响均有限；动应力与加速度经3 m 高的路堤后衰减，对桩网结构路基下部的网垫层已基本无影响。

The results show that the vehicle acceleration, the dynamic wheel load and offload factors increase with train speed, and distribute linearly. The safety of train operation and running comfort can meet the requirements when the high-speed train under secondary suspension passing through ballasted track subgrade structure. The dynamic displacement of the system is less influenced by train speed. The dynamic stress of subgrade surface increases with speed improving, and it is distributed as saddle along the lateral direction and as parabola along the longitudinal direction of subgrade surface. The dynamic stress of subgrade declines sharply along the depth of subgrade. The dynamic stress on 3 m depth below subgrade bed surface is about 16 percent of that of subgrade surface.

结果表明：车体加速度、动轮载和轮重减载率均随车速的提高而增大，呈线性分布；具有二系悬挂的高速列车通过有砟轨道路基结构时，列车的安全性及舒适度均能满足要求；系统动位移受速度影响较小；路基面动应力随速度的提高而增大，并在横向呈马鞍形分布，在纵向呈抛物线形分布；路基动应力沿路基深度方向衰减较快，在基床表面下3 m处，动应力只有基面的16%左右。

Results showed depth Of implantation greatly influenced the periimplant bone stress.Making the implants deep into lower bonier cortex could make stress transfer more evenl...

结果表明：种植体底部是否深至下颌下缘皮质骨，对种植体－支架应力的影响不大，而对周围骨的应力影响较大，在双颏孔间区将种植体深至下颌下缘皮质骨，更有利于应力均匀分布。

This paper presented a brazed residual stress predicting method based on neural network for stainless steel plate-fin structure.

由于影响不锈钢板翅结构在真空钎焊过程中产生的残余应力因素较多，这给残余应力的预测带来很大的困难，为此，本文提出一种基于神经网络的不锈钢板翅结构钎焊残余应力预测方法。

The results show that the mechanical properties of this PMMA depend strongly on the testing temperature. The Young's modulus and flow stress were found to decrease with increasing temperature at low strain rate. At the strain rate of 10^(-1) 1/s, strain soften was observed under all experiment temperatures. At high strain rate, with the temperature increase, the flow stress deceases remarkably while the failure strain increases, and the strain softening was also observed at the temperature above 333K.

试验结果表明：在准静态载荷下，随着温度的升高，材料的弹性模量和流动应力减小，在应变率为10^(-1) 1/s时表现出明显的应变软化行为；在高应变率(550 1/s)下，随着温度的升高，材料的流动应力逐渐减小而破坏应变增大，当温度超过333K时也有应变软化现象发生；在相同温度下，随着应变率的升高，材料的流动应力增大，但破坏应变减小。

But many theoretical and traditional means, such as material mechanics and induction, are used to compare the result educed by Software.

设计中出现了应力集中引起的大应力问题，和转鼓壁厚对应力影响的问题，都做出了解释和说明。

Fiber enlaced composite materials is widely used in engineering project .

纤维缠绕复合材料壳体在工程实际中得到广泛应用，其壳体力学性能相当复杂，本文在分析复合材料壳体层间应力的影响时，提出了复合材料壳体层间应力随纤维方向的改变有较大的不同，不仅分布形式不同，其最大层间剪应力所在的界面也各不相同。

The main creating aspects are finding and clarify such a fundamental physical process that the grain boundaries emit vacancies under compressive stress to induce solute non-equilibrium grain boundary dilution and absorb vacancies under tensile stress to induce non-equilibrium grain boundary segregation, formulizing the structural equations and the composition equations in force equilibrium in grain bounary region to describe this physical processes and the kinetic equations for non-equilibrium grain boundary segregation under tensile stress, calculating the modulus in grain boundary region from the expermental data of grain bounday segregation using the structure and coposition equations and calculating the diffusion coefficients of vacancy-solute atom complexes using the kinetic equation simulating the experimental results of grain boundary segregation.

本项目的主要创新点是，发现并阐明了弹性应力场作用下空位与晶界交互作用的基本物理过程：在张应力作用下，晶界会吸收空位，引起溶质非平衡晶界偏聚；压应力作用下，晶界会发射空位，引起非平衡晶界贫化。建立了描述此物理过程的晶界区力学平衡的结构方程和成分方程；？建立了张应力引起的非平衡晶界偏聚动力学方程？；用晶界区力学平衡的结构方程和成分方程？，首次通过实验测量计算出多晶材料晶界区的弹性模量；通过建立的动力学方程模拟实验结果，首次获得溶质原子－空位形成的复合体的扩散系数。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。