查询词典 velocity

There are four emphases in -research, for instance, flow state in pipeline, distribution of concentration and velocity, deposition-limit velocity and calculation of flow resistance or head loss.

研究重点主要集中在管内流动状态、浓度和速度分布、临界流速及阻力损失计算四个方面。

According to the studied results at present, the studied objects are mainly thin plate and beam about sound radiation mode, a method computed sound radiation mode of complex structure is presented in this dissertation, according to the results of the previous two chapter, a theoretical method to solve acoustical radiation mode and acoustical radiation efficiency of complex structure by boundary element method and acoustical radiation theory is posed, the acoustical radiation power is expressed as a Hermitian quadratic form, while the radiation modes is determined by general eigenvalue decomposing, and then the radiation efficiency is computed via the orthodoxy of radiation modes with regard to impedance matrix and average velocity matrix; lastly, the validity of the method is proved by pulsating sphere and radiating cube with analytical results. According to results of the form three chapter, the structure sound radiation sensitivity is studied in detail, the sound radiation power of structure can be expressed as positive Hermitian quadratic form, the sound radiation sensitivity can be expressed as two parts by partial differential with respect to design variable, which are sensitivity of boundary velocity and impedance matrix, combined with the theory of FEM and BEM, the structure sound radiation can be translated to the analysis of structure dynamic sensitivity and impedance matrix sensitivity. The theory posted in this dissertation is tested by the FEM software ANSYS and the software AAS programmed by author.

在前几章的基础上，通过结构声辐射的模态理论对结构的声辐射的机理进行了深入地探讨，针对目前声辐射模态的研究对象主要是简单的板和梁类结构，提出了一种计算复杂结构声辐射模态的方法，利用前两章研究所得的结论，将边界元方法与广义特征值的理论结合起来研究了复杂结构的声辐射模态与声辐射效率，先将结构的声辐射功率表示为一个正定的厄米特二(来源：ABb7C论文0909网www.abclunwen.com)次型，运用广义特征值分解求解了复杂结构的声辐射模态，然后利用声辐射模态关于阻抗矩阵与均方速度耦合矩阵的正交性，求解了复杂结构的声辐射效率，最后用具有解析解的脉动球与辐射立方体验证了该方法的有效性。

To validate the measurement results, the symmetric velocity field is measured by a hot-wire anemometer and simulated with a CFD software, and the unsymmetric velocity...

将其结果与声波法监测结果进行对比，三者在一定程度上吻合得较好。实验证明了声波法监测炉内烟气速度场的有效性，显示了良好的应用前景。

The main results of the investigation are as following:(1) Some important criteria for the design of multi-layer structure are acquired: the ratio of the layer thickness to the contact diameter should be controlled to a value about 0.8; increasing the number of the gradient layers and elasticity modulus of the top layer would benefit to the yield strength and the stress status at the interface.（2）By means of molecular dynamics simulations for a indentation and sliding process, it is discovered that dislocations of 45 direction to the surface occur in the surfaces layer, which is correspond to the direction of the plastic flows observed in the macroscopic continuous medium. The irreversible deformation caused by the dislocation and the atom piles at the surface are responsible for the irreversibility of the force response. They are also the main factors for the friction generation. The temperature and the indentation velocity have significant effects on the deformation behaviors of the material of the surface layer. The yield strength would increase obviously if the indentation velocity is greater than 10 m/s.（3）A method to evaluate the fracture toughness of coating by estimating the crack-density functionβof a Wicker''s indentation was proposed. Meanwhile a new surface treatment technology was developed using non-equilibrium plasma.（4）A MD-FE hybrid method and corresponding software was developed to analysis the tribological behaviors for multiplayer system.

研究主要内容和结果有：（1）得到指导梯度膜设计的几个准则：控制膜层厚度与接触半径比在0.8左右为宜；适当增加梯度层层数和顶层弹性模量，有利于提高抗屈服能力和改善界面处的应力状态；（2）通过对嵌入和滑动摩擦过程的分子动力学模拟，发现表层产生一个与宏观连续介质的塑性流动方向观测一致的45 方向位错；位错造成的不可逆变形和表面的原子堆积，是力的响应不可逆性的原因，也是构成摩擦力的主要因素；温度和嵌入速度对材料变形特性有显著的影响，当嵌入速度大于10 m/s时，屈服强度明显增加；（3）提出压痕裂纹密度系数β半定量判定膜层断裂韧性的方法；并开发出表面强化新工艺；（4）开发出分析表面摩擦学特性的MD-FE复合模拟方法和相应模拟软件。

The paper studied the impact of velocity analysis and NMO correction based on hyperbolic equation on stack velocity and to time and presented improvement method.

本文主要研究了基于双曲方程的速度分析和动校正方法对叠加速度和 t0 时间的影响，并提出了改进的办法。

Based on the low-velocity impact test, 4 major modes of low-velocity impact damage including delamination and matrix cracking were taken into account FEM simulation.

从z-pin增韧复合材料层合板低速冲击实验出发，考虑了复合材料层合板在受低速冲击时的分层及基体开裂等四种损伤形式，引入适当的损伤判据，对T300/3234碳纤维树脂基复合材料层合板的低速冲击损伤过程进行有限元模拟。

In addition, three special measures are introduced to guarantee the precision of solution, which are the pressure correction formulation to meet the impressible condition, the velocity correction formulation to avoid the error accumulation and a stability term addition to eliminate the velocity oscillation.

另外，本文还三种措施来提高晃动问题的精度，即通过压力修正来精确满足不可压条件、通过速度修正精确跟踪液面和通过引入稳定项避免解的振荡。

Our research analyzes comprehensively the sand data, such as thickness distribution, velocity distribution, frequency distribution of sand incipience velocity, expatiates the behaviors of these two sand incipiences in wind-blown-sand flow, then our research amends some deficiency of relative researches.

本文全面分析了沙粒浓度分布、速度分布和沙面上起动沙粒速度参数的频率分布等，阐述了两种沙粒起动方式在风沙流中的不同表现，并对相关研究资料中的不足进行修正。

So for the moment, we recommended in the newguideline that to measure pulse wave velocity, carotid artery pulse wave velocity which means arterial stiffness, because we have good evidence that it is an independent predictive value for cardiovascular events.

所以目前，我们在新的指南中推荐测量脉搏波速度，测量颈动脉的脉搏波速度，这个指标就是代表动脉僵硬度，因为我们有很充分的证据证明它对心血管事件有独立预示价值。

The results demonstrated that with the increase of twisting velocity, the torque on the hollow structure changes indistinctively. In case of increasing die velocity and target strain rate, the forming force of hot forming and gas pressure of superplastic forming will increase.

研究表明，扭转速度的提高使扭矩仅有较小的变化；当模具速度和应变速率提高时，热成形的成形力和超塑性成形的气压将提高。

In the days of sailing vessels the crew were afraid they would be becalmed on the ocean.

在使用帆船的时代，船员们担心他们会因为无风而无法在海洋上航行。

As long as foreign donors pay the PA's salary bill, few expect a new intifada.

只要外国继续为巴权力机构的薪水买单，希望发动新暴动的人便寥寥无几。