截面线

Firstly, the developing principles of the cylindrical internal helical gear are proposed through analyzing the movement and geometry requirements, which provides continuous contact between the mating gear surfaces. The tooth surface of the internal helical gear in the new gearing can be imagined as being generated by the normal section of the conjugated surface of the ball-tooth, moving along the radial projection of helix line of the tooth-root circle. Also, the proposed surface can be approximate tangent to the conjugated surface of the ball-tooth along a spacial curve.

首先，通过分析保证行星轮作螺环运动时与内斜齿轮实现连续啮合传动的运动和几何条件，提出了圆柱内斜齿轮齿面的两种形成原理：即由球齿运动包络曲面的法截面沿其齿根圆螺旋线在径向的投影进行拓展所形成的内齿面，以及与球齿运动包络曲面呈近似相切接触的等螺距齿面构成的内齿面。

By using the continuity equation and weak hydrody-namic interaction theory in the relaxation time approximation, the spatial variation of the radar scattering cross-sec-tion has been proved as proportional to the gradient of current velocity.

在浅海海流速度垂直分布廓线为均匀的假定下，由流体连续性方程和弛豫时间近似下流体力学弱相互作用的理论，已证明雷达散射截面的空间变化正比于海流方向上海流速度变化的梯度。

In the Sixth Chapter, the Wavelet analysis method is introduced in discussing some acoustic imaging problems related to the physical background of the ultrasonic detection. In the light of the solution of some theoretical problem in the 2D Wavelet transmission of two components form, the enhancement and identification of the spotty and fibriform faults of the acoutic image, along with two acoustic image deblurring methods based respectively on the acoustic physical feature analysis and the acoustic image's spatial feature analysis of the object, are realized. Therefore the image degeneration problem resulting from the acoustic beam diffusion or the acoustic focus diffusion in the ultrasonic detection are effectively improved. The software for this purpose has also been developed.

第六章首次应用小波分析的方法，研究了与超声检测的物理背景有关的一些声象处理问题，在解决了二分量形式的二维小波变换中的一些理论问题的基础上，建立起了对声象中点状和线状缺陷目标的增强与分离方法，以及分别基于目标的声学物理特征分析和基于目标声象空间特征分析的二种声象弥散消除方法，实验分析结果表明，这种方法较好地解决了超声检测中由于声束截面或声焦点扩散所造成的成象退化问题。

As the tube is the arc horn tube with irregular section and inextensible special-shaped pieces, and white lines and red lines are not allowed in the groove at the back, the film paste can only be done by manual work and the location of sing by human observation

因管为不规则截面的弧形喇叭管，为非可展开的异型件，且背面凹槽处不得有白线和红线，菲林的粘贴只能用人工完成；标志的位置只能人工观察

Fifth, The linear distribution of metallographical microstructure of laser-cut crosssection for pipe and plate, which is a new method developed for the investigation of heated conditions during laser cutting, was firstly studied by the method of quantitative metallographic examination, and their different heated conditions were verified on the base of the measured results.

另外，首次采用定量金相测试的方法，研究了管材和板材切口横截面金相组织的线分布，并以此测量结果验证了管材和板材受热情况差别，从而发展了一种新的研究激光切割过程受热情况的方法。

The bifurcation and chaos behavior of impact and rubbing fault rotor system caused by the parameters of nonlinear rigidity, rotor rotating speed, eccentric mass is analyzed, in the numerical value analysis method. The bifurcation diagrams, maximum Lyapunov exponent diagrams, Poincaré maps, phase plane portraits, trajectories of journal center, time-history curve, amplitude spectra diagrams of the rotor motion are used. The convert and evolution course of periodical response, quasi-periodical response, double-periodical bifurcation, chaos of the system response is analyzed.(3). It is deduced that the general differential equation of bending-torsional-pendular coupling vibration about rotor with the gyroscopic moment. On the basis of this equation, the general differential equations of coupled bending, torsional and pendular nonlinear vibration about rotor with unbalance character and rubbing character are deduced.

2建立了具有非线性刚度的转子系统在非稳态非线性油膜力作用下的径向碰摩动力学微分方程，并应用含高阶余项的非线性动力方程的线性化数值法研究了此类系统响应的复杂动力学行为，利用转子响应的分岔图、最大Lyapunov指数曲线、Poincaré截面映射、时域波形、相轨线、轴心轨迹、幅值谱等图形分析了系统响应的周期运动、拟周期运动、倍周期分岔、混沌等运动形式的转化与演变过程，重点研究了非线性刚度、转子转速、偏心质量等系统参数对碰摩故障转子系统的分岔和混沌行为的影响。

Methods:Samples of ACG,ACGP and β TCP in the size of 10 mm×3 mm×2.5 mm were prepared and implanted subperiosteally into the mandible deffects in 48 rabbits .

可吸收性微晶玻璃、烧结型可吸收性微晶玻璃粉植入兔颌骨人工缺损区后观察X线片、横截面积测量、光镜、电镜及能谱分析的变化。

In this paper, The delta wing of Mach number 0.8 at an attack angle of 21. 8 degree is simulated by our program. Then, using the visualizing program, we map the figures of space streamlines, cross streamlines near the vortex axis, three dimensional vortex lines, cloud atlas for pressure and vortex and targer of particles.

在这一章里，我们先用所建立的计算软件数值模拟了来流马赫数为0.8、攻角为21.8°的三角翼的流场，之后以拓扑分析结果做指导，研制了一套数值显示流场、旋涡结构的软件，用该软件我们绘制了跨音速三角翼背风区涡轴附近截面流线、空间流线、三维涡量线、压力和涡量云图以及粒子屏痕图。

FEMOL is systematically applied to various moving boundary problems, including: membranes contact with rigid foundation, shape optimization of cross-sections of elastic torsional bar, seepage through a dam with a free surface, Mindlin-Reissner plates contact with rigid foundation, free Mindlin-Reissner plates on tensionless

三、将有限元线法分析推广应用到了一系列的动边界问题中，包括：薄膜接触问题，弹性扭转杆的截面优化问题，自由液面的稳定渗流问题，中厚板理论与刚性地基的接触问题，无拉力Winkler地基上自由中厚板问题，理想弹塑性扭转问题，理想弹塑性Ⅲ型裂纹问题。

In the medium scale experiment line, the best concentration of coagulation was about72% It was showed that the increasing of the concentration of was good for decreasing surface puckers and made the cross-section shapes tend to circle.

在中试线上，最佳凝固浴浓度为72%左右。对凝固浴浓度与纤维表面形态的研究表明：凝固浴浓度的升高有利于降低纤维表面沟槽，截面更趋于圆形。

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％。