查询词典 propagation

The computational flow of light propagation and the key techniques of visualization are presented. An optical system was employed to verify the correctness and feasibility of quaternion method in the calculation of beam propagation, and the pincushion distortion caused by the optical system was successfully simulated.

通过对某光学系统的仿真分析，成功仿真出图像经过光学系统产生的枕形畸变，证明四元数方法在光线传输运算中的正确性与可行性，为复杂光学系统的空间光线传输计算提供了另一种方法。

A tolerance analysis procedure based on homogeneous transform and Monte Carlo Simulation is proposed in this research. The propagation of variation in 3-D space is treated as propagation of errors during transformations of Cartesian frames, which are set up on the Key Characteristic Points.

通过定义车身装配坐标系统，根据微分运动的原理，建立了计算车身零部件位姿关系的数学模型，对典型公差语义的数学表达进行了研究；并应用蒙特卡洛模拟，对关键特征点偏差传播的统计特性进行了分析。

One of the prominent characteristics of the self-learning neuron is thatit has a forward-channel, a backward-channel and a leamer, This makes each neuron in a self-learning BP network accomplish the forward propagation of message, backward propagation of errors, and modification of its parameters independently, and hence makes the network implement parallel computing easity.

由自学习神经元组成的自学习BP网络可以真正做到正向传播信息、反向传播误差及学习的并行化。

Rapid propagation of Lilium lancifolium Thunb. was introduced in five aspects: the reproduction of bulblets,the extantion of bulblets, the redifferentiation of bulblets through callus, the environment factors on bulblets propagation. In addition,the valuable components were analogized.

本文从小鳞茎的增殖、小鳞茎的膨大、愈伤组织诱导再生小鳞茎、环境因子对小鳞茎生长的影响四个方面探索了组织培养快速繁殖宜兴百合的方法，大大提高了宜兴百合的生长量；并通过组培百合与栽培百合进行有效成分的对比分析，以此保证组培百合的品质。

Depending on the character of Lamb wave propagation , thedamage scat tering signals were time reversed and reemit ted to the damage , and then they will arrive at the damage synchronously so that the damage scat tering signal caught again will be amplified. Details about the time reversal amplifying process were analyzed and given. Based on the focalization ability of time reversal theory to the wave origin , the wave propagation was rebuilt by an image method which displays the damage as the focusing point .

根据信号传播自身的特性，研究采用时间反转聚焦方法使损伤散射信号能量叠加放大，从而提高信号的信噪比，分析给出了具体的损伤信号时间反转聚焦增强过程；利用时间反转法对波源的自适应聚焦能力，重建信号传播波动图，通过信号聚焦显示损伤位置和区域。

The coupling mechanism, frequency domain characteristics and propagation rule of three propagation paths of partial discharge signal

该方法所采用的测量频段较高，抛弃了以往定位方法中常用的"慢波"，不会受到窄带干扰和低频磁场耦合信号的影响；不存在定位盲区；具有足够的脉冲分辨率；所采用的频带较窄，相应的传感器较易制作。

Introduced the mathematics theories foundation of the symplectic schemes, include the commonly established methods for construction symplectic schemes, which are symplectic Runge- Kutta method, symplectic propagation techniques and generating function method. A minimization of the truncation error-function and optimal Courant-Friedrichs-Levy number schemes are well established using sympletic propagation techniques.

介绍了辛算法的数学理论基础，包括辛算法常见的构造方法：辛Runge-Kutta法，辛传播子技术及生成函数法，利用辛传播子技术结合误差最小化及稳定性Courant-Fredrichs-Lewy条件数最大化的两种优化方案，构造了新的传播子系数；(2)。

The development of saprolite is realized by the progressive propagation of the weathering front of low permeable rock blocks, and the condensate from the moisture and the unsaturated seepage flow are the key agents of the propagation process.

腐岩发育是通过低渗透岩石结构体风化前锋的渐进性扩展实现的，非饱和带高湿度空气形成的凝结水和降水入渗形成的非饱和渗流是该过程的核心动力。

The results make it known that: in the same cycle degree, the crack propagation depth of finite element is greater than experiments, the inaccuracy between expriments and computer simulation tracing is lower than 10%, the tracing conclusion is securer than the experimental one; both directions of crack propagation are not identical.

当接管区出现裂纹时，则在疲劳载荷的作用下会加速扩展，从而降低设备的使用寿命，并且可能发生一些毫无征兆的事故。因而研究并掌握接管区表面裂纹的疲劳扩展特性对于预防接管区的失效破坏具有一定的学术和工程价值。

In addition, Snell's law is applied, and traveltimes of waves from neighboring nodes are considered at the same time to determine the effective propagation area of the current secondary source. Thus, many unnecessary propagation directions are excluded.

在子波传播的计算上，利用斯奈尔定律，同时参考来自邻近节点的波的走时，来限定当前子波传播的有效区域，排除大量不需要计算的子波传播方向。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。