波点

In this paper, on the base of paraxial approximations, we present a set of absorbing boundary conditions of 3D elastic wave equations and apply to the 3D elastic wave numerical modeling in isotropic medium.

本文基於傍轴近似法提出了计算三维弹性波方程的吸收边界条件公式，表示了各边界面、边棱和角点处波场所满足的单程波方程，并在三维弹性波数值模拟中进行了应用。

The point at which the incident wave, reflected wave, and mach fronts meet is called the "triple point"

入射冲击波、反射冲击波与马赫波波阵面汇合之点叫做"三相点。"

METHODS: Samples series of beat to beat cycles were selected to prepare Poincare mapping to describe TWA distribution.

选取连续心跳周期中T波窗口内的采样点序列做散点图，描述T波交替的分布状态。

The various colours significant of various degrees of vitality (white, yellow, crimson, vermilion, cinnabar): their degrees of brilliancy: their magnitudes revealed up to and including the 7th: their positions: the waggoner's star: Walsingham way: the chariot of David: the annular cinctures of Saturn: the condensation of spiral nebulae into suns: the interdependent gyrations of double suns: the independent synchronous discoveries of Galileo, Simon Marius, Piazzi, Le Verrier, Herschel, Galle: the systematisations attempted by Bode and Kepler of cubes of distances and squares of times of revolution: the almost infinite compressibility of hirsute comets and their vast elliptical egressive and reentrant orbits from perihelion to aphelion: the sidereal origin of meteoric stones: the Libyan floods on Mars about the period of the birth of the younger astroscopist: the annual recurrence of meteoric showers about the period of the feast of S.

357显示出不同程度之生命力的缤纷色彩（白、浅黄、深红、朱红、银朱）；诸星之亮度；一直包括到七等星、以等级标志的诸星之大小；诸星的位置；御夫座；沃尔辛厄姆路；大卫的战车；土星光环；螺旋星云凝固后形成有卫星的恒星群；两重大阳相互依存的旋转运动；伽利略、西蒙。马里乌斯、皮亚齐、勒威耶、赫歇耳、加勒等人各自独立地同时所做的发现；波得和开普勒所尝试的距离的立方与回转次数的平方的体系化；多毛的众彗星那几殆无限的被压缩性，以及自近日点至远日点那广漠的远心的重返大气层的椭圆轨道；陨石的恒星之起源；年纪较轻的天体观测者诞生的那个时期火星上所出现的&暗波&现象；每年在圣劳伦斯节前后降落的陨石雨；每月都发生的所谓&新月抱旧月&现象；关于天体对人体的影响的假定；威廉。

The points of maximum amplitude are called antinodes.

振幅最大的点称为波腹，振幅为零的点称为波节。

The cutoff conditions of metal-clad waveguides or loss dielectric waveguides are discussed. The effects of metal-cladding on the cutoff condition of graded index waveguides are analyzed at first. The principle of cutoff intensity modulator has discussed in detail.

本文首次提出一种适合于分析含金属覆盖层的均匀和渐变介质波导在截止点附近的光学特性的近似的解析方法，并对金属覆盖层的均匀阶跃介质波导在截止点附近的模传播特性作了全面的分析，所得到的结果同精确的数值解结果相吻合。

We suggest a method abandoning the search for common converted points and adjusting polars, and taking receive point as fictitious source, and using one-way wave equation performance to converted wave migration in shot domain.

抛开常规的转换点位置估计及极性校正，把检波点作为虚拟震源，利用单程波方程实现转换波记录的炮域偏移处理。

Basic characteristics of cosine transform spectrum were analyzed, where contour lines of 2D cosine transform of point mass present the shape of a quarter of concentric circles and the number of counter become small along with the increasing of wave numbers. The spectrum of vertical rectangularcylinder put up periodic zero counters which mark off quadrate areas, the values of counter in each areas alternately change between the plus and the minus, and with the increasing of wave number, the values of counter present attenuation character alike e exponent.

分析了点质量和直立矩形柱体重力异常余弦变换谱的基本特征：点质量二维余弦变换谱等值线呈1/4同心圆形状，等值线随着波数的增大而变稀；直立矩形柱体谱出现了周期性变化的零等值线，该等值线将非零等值线划分为a×b个矩形区域，而且等值线值在各矩形型区域中正负交替变化，随着波数的增大，不同的矩型域中等值线值呈e指数衰减特征。

A new method of automatic segmentation is developed based on the extreme point properties of wavelet transform. The method consists of two main steps: 1. Using the multi-resolution properties of wavelet transform, we can get the information of shape variation with space coordination.

该方法包括两个主要步骤，一是利用小波变换的多分辨率特性得到测井曲线的形态特性随空间坐标的变化信息；二是利用小波变换过零点的特征在不同尺度上的反映，提取不同尺度下的奇异点作为分层的待参考点，结合实际情况最终确定分层点。

This solution was expressed a function of offset, compressional and shear waves velocities, the traveltime of P-SV converted waves.

Schneider（2002）从一个关于转换点的三次方程中推导出了P-SV转换波转换点位置的一种解析解，这种解是偏移距、横纵波速度和P-SV转换波旅行时的函数。

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％。