圆盘

The general shape of the average nebula is that of a thin circular disk somewhat thick in the center.

星云最常见的形状是中间较厚边缘较薄的圆盘。

The exact energy flow pattern on the axis of a circular disk by transient excitation is presented.

摘要本文给出了在瞬态均匀电流分布激励下，圆盘轴线上能量衰减的精确解。

The g eral shape of the average nebula is that of a thin circular disk somewhat thick in the center.

星云最常见的形状是中间较厚边缘较薄的圆盘。

If a length of string that is wrapped around the periphery of a circular disk is then gradually unwrapped, a point at the end of that string will follow a curved path that is known as an involute of the circle that is represented by the disk.

如果字符串长度是围绕周边的圆盘，然后逐步展开，这一点在年底该字符串将采取曲线路径，被称为渐开线的循环，所代表的磁盘。

Central cracked circular disk; split Hopkinson pressure bar; dynamic fracture ; dynamic stress intensity factor

中心裂纹圆盘；分离式霍普金森压杆；动态断裂；动态应力强度因子

The circular disk is somewhat easier to machine and to load than the tensile 3 specimen; moreover, if required, several calibration points can be obtained from a single load.

基於试片加工与负载的方便性，而且可以只从单一负载就可取得多点资料，所以圆盘试片受上下压力实验法是比较被推荐使用的方法。

This project is intended to modify circular disk loaded in diametral compression method, from concentric load to distributed load on a small area to reduce error. Firstly, we will establish digital Photoelasticity system, manufacture specimen, design loading frame, and then the experiment will completed.

本计画主要目的在减少误差而修正圆盘试片受上下压力实验法的数学理论依据，负载从集中力改为有限范围的均布力，经过理论推导后，以自行组合之数位光弹仪实验比较两者求出的材料条纹系数值。

The fracture toughness testing technique for the central cracked circular disk specimen is given to investigate the fracture behavior of brittle material polymethyl methacrylate under pure mode Ⅰ, pure mode Ⅱ and mixed-mode loadings. The experimental results show that the load distribution angle is always greater than 8° for all different loading conditions.

给出一个中心裂纹圆盘断裂试验的较完整的试验技术，并用此试验技术在岛津材料试验机上对有机玻璃(polymethyl methacrylate， PMMA)这种典型的脆性材料成功地进行纯Ⅰ型、纯Ⅱ型和复合型加载条件下的断裂试验。

N experiment combining flow visualization and temperature measurement is carried out in the present study to investigate the possible presence of new inertia-driven vortex rolls and some unique characteristics of the time-dependent mixed convective vortex flow resulting from a high speed round air jet impinging onto a heated horizontal circular disk in a vertical cylindrical chamber.

bstract：本篇论文利用实验流场观测方法及温度场量测方法对於垂直圆柱容器中一高速空气圆形喷流冲击至一加热圆盘之可能产生新的惯性力驱动涡流和一些独特的周期性混合对流涡流流场特性进行研究。

A type of quick-opening valve whose orifice is opened and closed by a disk that pivots on a shaft in the throat of the valve.

一种快开式阀门，其孔口的开启和关闭靠装在阀门颈部枢轴上的圆盘。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。