粒子运动

Furthermore, the general formula is illustrated as the weighted summation of historical position states, so as to prove that in terms of cumulative iterations, parameters of PSO have an inherent forgetting characteristic in probability, moreover the searching mechanisms of canonical PSO and Barebones particle swarm are almost the same.

通过将粒子运动的一般性描述图解为历史状态加权和的形式，进一步证明了PSO参数随迭代周期的积累，在概率意义上的遗忘特性。分析表明在经过一定周期的搜索后，标准PSO方法同Barebones粒子群方法(Barebones particle swarm， BBPS)具有近似的搜索机制。

The main research work of this paper are focused on following areas:(1) Based on review of the theory and methods on measurements of particle fields, a new idea for obtaining particle size and velocity distribution within a spray through imaging the particle field with a laser light sheet was put forward;(2) A DPIV (Digital Particle Image Velocimetry) system, is fit for velocity measurements of low speed flows, was developed and expended to particle size distribution measurement;(3) An arithmetic for particle velocity field reconstruction was developed, and the velocity distribution of water mist was also obtained;(4) A software system for particle analysis, which based on image geometry emend, de-noise and image partition was developed, the parameters such as particle size distribution, mean diameter, number of particles, minimum and maximum diameter can be got with this system;(5) A water mist system was developed and its characteristics, such as droplet velocity, size distribution, number of droplets and spray cone angle under different conditions were obtained from experiments with PIVS;(6) The measurement results of water mist characteristics with PIVS were compared and analyzed with the simply simulated results, and in addition, in order to verify the accuracy of PIVS, some experiments were conducted with the standard particles, such as glass-ball with known mean diameter of 50μm and 115μm, metallic coated tracing particle with mean diameter of 12μm;(7) Some experimental studies on interaction of water mist with liquid pool fires were conducted.

本论文的主要工作包括以下几个方面：（1）在对粒子场测量的相关理论和具体方法进行综述分析的基础上，提出了通过采用激光片光对粒子场进行成像以获取其粒径和速度等参数分布的新思路；（2）研制了适宜于低速流动速度场测量的DPIV(Digital Particle Image Velocimetry)系统，并使其实现了对粒子场粒径分布的测量功能；（3）研制了基于粒子运动轨迹的速度场重建算法，获取了细水雾雾场的速度分布；（4）研制了基于几何校正、去噪、图象分割等图象处理方法的"粒度分析软件系统"，该系统既可分析给出粒子场的粒径分布直方图和平均粒径，还可给出粒子的数目以及最大、最小粒径等信息；（5）建立了一细水雾发生系统，并应用上述方法对不同压力条件下细水雾系统的雾场特性（如速度分布、雾滴粒径分布、雾滴的数目、喷雾张角以及雾化长度等）进行了实验测量研究；（6）对细水雾特性参数的PIVS测量结果与计算机简单模拟计算结果进行了定性比较分析，并利用平均粒径为50μm和115μm的玻璃球以及12μm的标准示踪粒子对PIVS系统的粒径和速度测量结果进行了实验验证，同时对其局限性进行了分析讨论；（7）对不同工况条件下细水雾与油池火相互作用的过程进行了模拟实验研究。

Based on the model of DLA, this paper simulates the process of aggregation's growth for random walk particles from local area on two-dimension Euclidean plane. The aggregation is confined to Euclidean circular plane for large enough particle walking area and far enough partial source distance. The centre of the Euclidean circular plane is on the line between the particle source's symmetric centre and the seed particle, and is more closer to the particle source than the seed particle. Though the rate of aggregation growth is different in different directions, the whole aggregation shows fractal structure.

以DLA模型为基础，模拟研究了在二维欧几里德平面上由局部区域内产生随机运动粒子的聚集生长过程，发现对于足够大的粒子运动区域和足够远的粒子源距离，凝聚集团大体上被限制在欧氏圆形面内，圆心在粒子源对称中心和种粒子的连线上，且比种粒子更加接近粒子源；凝聚集团朝各个方向的平均生长速率虽然不同，但整体仍呈分形结构。

As for the other cases and system structures, such as elliptical and quartic potential, parametric noise exciatation, some satisfactory analytical results are also obtained by studying the particles system in detail.

对于其他情形和结构下的Brown粒子运动系统，包括椭圆型和四次方型势能形式，以及参激噪声激励下的Brown粒子运动系统，本文都做了详细地研究，并取得了令人满意的结果。

In this paper, by using the method tO get the arithmetic solution and with the formula calcuatring the moving particle trace in magnetic field, corrected be computer, it is easy to get the arithmetic solution, in addition,the result of solving is giv...

本文用求数值解的方法，使用经过计算机修正后的计算磁场中粒子运动轨迹的公式，可以非常迅速、简单地得到带电粒子在磁场中运动轨迹的数值解，并以图像给出解的结果。

The application of polar coordinates system in the CNC LATHE-MILLING;2. A fast particle-moving algorithm for particle-in-cell simulation of plasmas in polar coordinates system was proposed, in which the local rectangular coordinates approximation was used in the area near the position of the charged particle at every time step.

提出了一种在极坐标系下快速推进带电粒子的等离子体粒子模拟算法，该算法在每个时间步长内对带电粒子位置附近的区域采用局部直角坐标系近似，并通过坐标变换，得到粒子运动方程求解的显式格式，从而避免了极坐标系下隐式格式直接迭代求解所带来的容许误差，并提高了计算效率。

The motion of two charged quasiparticle s on an infinite Chain in a uniform electric field is presented.

本文研究了在均匀电场中位于一维长链上的两带电准粒子的运动，给出了一般情况下的精确解，并讨论了两准粒子运动的动态定域性和复合、分离等问题。

The interaction of electromagnetic waves and electriferous particles was considered and the equation of motion for an average electron in the plasma was established. And the effective permittivity of flame was deduced.

文中在考虑带电粒子运动与电磁场之间耦合作用的基础上，建立等离子体中带电粒子运动方程，推导了与火焰微观特性相关的复等效介电系数表达式。

Against the characteristics of particles' movement in FST, the dissertation utilizes the advantages of three particle tracking methods, puts forward integrated particle tracking strategy, and realizes the particle tracking effetely.

针对脱硫塔中粒子运动的特点将3种方法有机地结合起来，充分利用了三种粒子跟踪算法的优点，实现了粒子轨迹的有效跟踪。

For non-intense beams,particle trajectory can be obtained by multiplying linear transport matrices. For nonlinear transport of intense beams,the influence of space-charge effect on beam transport needs to be taken into account,and self-consistent solution should be derived because of the interaction between charged particle distribution and space charge field. In the program,components and currents are divided into equal intervals,respectively,and each interval is treated as a uniform solenoid field.

程序在计算非强流脉冲束流的线性传输时，粒子的轨迹通过矩阵的直接相乘计算得出；程序在计算强流脉冲束流的非线性传输时，需要考虑束流中的空间电荷效应对束流传输的影响，在束流运动过程中，空间电荷场也在不断地变化，而且粒子运动的轨迹与空间电荷势又是相互依赖的，因此需要求得一个自洽的解，先把元件分成若干均等的区间，把电流分成若干等份，后采用束流电流迭代与元件区间迭代的计算方法。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。