转换点

Using real data from a seismic exploration, we achieved the migration sections of converted wave beneath volcanic area, and it is proved that the method is effective for computing common asymptotic conversion point and pre-stack time migration.

实际资料的成像结果表明，本文采用的近似转换点计算以及转换波叠前时间偏移方法是有效的。

This algorithm lights five pixels in a loop between the coordinate information of line's start and end points. Therefore, the speedof generating of straight line can be accelerated. Compared with the four-step, it is the speed that increased by about 20% while the complexity is almost the same. Meanwhile the five-step still maintains the precise of the traditional line scan conversion algorithm.

该算法过给定的直线的始点和终点，可以一次计算得到并且点亮五个象素点，从而较传统的直线扫描转换算法成倍地提高了直线的生成速度，与著名的"四步法"相比，几乎没有增加复杂性，而速度则提高约20%，同时仍然保持传统直线扫描转换算法的精度。

This technology is very useful in natural language understanding, text indexing and language model building, etc.

因此，如何找到文本中的主题转换点是语言处理中的一个重要内容。

The first rank derivative is a reflection of curve change and its rate, at certain range, if the sign of the first rank derivative has changed, the logging value of the correspondence depth point means maximum in this range; the second rank derivative is the knaggy property reflection of curve, at certain range, if the sign of the second rank derivative has changed, the correspondence depth point represent the inflexion of geophysical logging curve, it＇s also a turning point of the reflection of knaggy change property of the curve, it is the interface of stratum.

测井曲线的值是深度的函数，测井曲线的一阶导数表示了曲线变化的趋势和变化的快慢，在某一范围内，当一阶导数呈现符号转换时，相对应的深度点的测井值即为该范围内极大值；测井曲线的二阶导数则表示曲线的凹凸性，在某一范围内，当二阶导数呈现符号转换时，相对应的深度点代表了测井曲线的拐点，即反映曲线凹凸性变化的转折点，亦即地层的分界面。

As applications, we prove the following results: If / has pointwise pseudo-orbit tracing property, for any k ∈ Z+, and fk is chain transitive, then for any k ∈ Z+, fk has open set transitive ; If f has pointwise pseudo-orbit tracing property, and for any n ∈ Z+,fn is chain transitive, then f has sensitive dependence on initial conditions; If f is open set mixing and has pointwise pseudo-orbit tracing property, then f has property P; Let f :→ be a homeomophism, then f is pointwise pseudo-orbit tracing property if and only if the shift map σf is pointwise pseudo-orbit tracing property.

作为应用，证明如下结论：若f具有逐点伪轨跟踪性质，且对任意k∈Z+，fk为链转换的，那么对任意k∈Z+，fk为开集转换；若f具有逐点伪轨跟踪性质，且对任意n∈Z+，fn为链转换的，则f具有初始敏感依赖性质；若f为开集混合的，且具有逐点伪轨跟踪性质，那么f具有性质P；设f：→是同胚映射，那么f具有逐点伪轨跟踪性质当且仅当移位映射σf具有逐点伪轨跟踪性质。

Common conversion point binning and non hyperbolic normal moveout are two key points to CCP stacking for converted waves.

转换波共转换点(CommonConversionPoint简称CCP)叠加的关键在于CCP抽道集和非双曲线正常时差校正NMO 。

Otherwise, certain conversions are needed at the point of the VoIP gateway which incurs operating costs.

否则，需要有一定的转换点上的VoIP网关的承担运营成本。

But occasionally, there were lots of inversions, like in a circle, so regions grew as necessary.

由于大多数的区域都是矩形的，并没有太多的临界转换点，所以通常区域面积不大，但有时候有些图形有许多转折点，例如圆形，那区域也就会跟着变大。

Due to the multilayered medium is more close to the real situation, Thomsen's definition of velocity ratio between compressional and shear waves is more accurate.

Thomsen于 1999年提出多层介质条件下的共转换点计算公式，其假设前提与实际情况更为接近，对纵横波速度比的定义也更为精细。

In order to distinguish these two types of transitions, a state recognition method is introduced. We firstly propose a variable contact set in which the contact points on the robot body are defined to represent the alternation of the contact states logically. Then, by predefining thresholds for the contact forces, the state transition can be well recognized.3 As another research topic, the local tracking control according to the pre-acquired state transition trajectories plays an important role in realizing the non-regular motion for the humanoid robot.

在状态转换识别方法上，本文提出了接触点集合的概念，对接触状态的变化进行逻辑上的表达；再结合接触点集合的变化情况，通过设定接触力阀值来实现对状态转换的识别。3根据给定的状态转换轨迹进行局部的跟踪控制，是本文实现类人机器人非规则运动的另一个重要研究内容。

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称；三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起，称之为挽歌体诗人或者史诗诗人，他们被称为诗人，似乎只是因为遵守格律写作，而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。