振

Backward single and double scattering arecompletely polarized but the decorrelation between their phases produces unpolarizedcomponent in total scattering light.Enhanced backscatterig is unpolarized.

后向的单次散射和二次散射光基本上是完全偏振的，它们的相同偏振分量之间由于缺乏固定的位相关联，而在总散射光中产生了明显的非偏振成分，增强后向散射是非偏振的。

In the dissertation, we presented a method to calculate the start oscillation length and real starting asynchronous velocity parameter. In the meantime, when the effect of two or more azimuthally asymmetric space harmonics in the high power broadband helix TWT on the start oscillation length and real starting asynchronous velocity parameter were also analyzed.

数值计算表明：增大渐变的强度，就可以增加起振长度，而且当渐变的强度增大到一定值时就不会产生返波振荡；当衰减器靠近输入段时，起振长度就随之减小；当增大衰减器的长度或减小衰减量时，相对起振电流随之减小，可见衰减器对起振条件确实有明显的影响。

The head is slowly turned 90° toward the side where nystagmus is induced less intensely. Then the head is rotated 180° rapidly toward the opposite side. This article reports three cases of the ageotropic form of HC-BPPV that were cured by rapid head rotation. The three cases demonstrated that rapid head rotation was an effective maneuver to treat cupulolithiasis on the utricle side. It is recommended that rapid head rotation can be used for therapeutic diagnosis: If nystagmus subsides immediately after this maneuver, the diagnosis is cupulolithias is on utricle side. If nystagmus changes into the geotropic form, the diagnosis is cupulolithiasis on canal side or canalolithiasis in the anterior arm of horizontal semicircular canal. A repositioning maneuver for geotropic form can then be applied to treat these patients.

逆地眼振型水平半规管良性阵发位置性眩晕的3种耳石可能位置如下：水平半规管前臂的管耳石、管侧的顶帽沉石(canal side cupulo-lithias1s)与囊侧的顶帽沉石，本文报告3例以快速转头治疗逆地眼振型水平半规管良性阵发位置性眩晕成功的病例，显示快速转头法对囊侧的顶帽沉石具迅速有效的治疗效果，对於逆地眼振型水平半规管良性阵发位置性眩晕的治疗，作者建议先以快速转头作治疗性诊断，若病人马上复原，诊断为囊侧的顶帽沉石；若眼振转为向地型，则诊断为水平半规管前臂的管耳石或管侧的顶帽沉石，进一步再以向地型的耳石复位法治疗病人。

As a further studying, the "beat" oscillation phenomenon appearing beforce the chatter occurs is analyzed and it is found that there is a self-excited vibration frequency f during the rilling. Farthermore, if the frequency f is infinitively close to one of the natural frequencies of the rolling mill system then an instability will occur.

作为颤振振因的深化研究，对颤振出现前的&拍振&现象进行了分析，推证了轧制过程中有一个自激频率f存在，而且当它与轧机系统的某个固有频率无限接近时会立即引起轧机工作的不稳定。

Result shows that the pouring techniques of concrete have little influences on workability, slump, spread, surface crack and temperature control, but more on laitance.

结果表明，混凝土浇注工艺对和易性、坍落度、扩展度、表面裂缝、温度控制影响较小，对浮浆的影响较大；均匀振捣与超振剪力墙的浮浆厚度较大，抽芯试样强度合格，未振捣的剪力墙的浮浆厚度较小，但抽芯试样强度不合格；每层浇筑厚度宜控制在0.8～1m，且均匀布料振捣，该值能为现行规程的修订与完善提供试验数据参考。

Polarization encoding is a novel format and has more advanges such as natural power equalization, better polarization characteristics,less power penality,and so on,which can greatly reduce the nonlinear effects,suppress the PMD,and improve the spectrum efficiency,so its realization will accelerate the development of high-speed fiber communications.

偏振编码是一种全新的编码格式，它具有天然的功率均衡性、偏振特性好、功率代价小等优势，可大大降低系统中的非线性效应、抑制偏振模色散、降低误码率、提高谱效率，因此偏振编码通信的实现将推动高速光纤通信更快地发展。

Secondly, the mathematical models for VE type three eccentric chaotic exciter and forrame rum oil system of chaotic vibratory roller are built. The numerical simulation and chaos identification are finished under different parameters of the exciter. The relationships between the chaotic characteristics of the exciter as well as the rame rum oil system and the parameters of the exciter are investigated.

其次，建立了& CVE—2型三偏心混沌激振器&和混沌振动压路机&机架—振动轮—土&系统的数学模型，并在激振器的不同参数条件下，对数学模型进行了数值仿真和混沌识别；研究了&混沌激振器&和&机架—振动轮—土&系统的混沌特征与激振器参数之间的关系。

Through the conductor self damping measurements verified the rationality of improved formula for calculating transmission line self damping; through the damping tests of stockbridge damper is installed in different location, indirectly verified the correctness of the location optimized calculation of the stockbridge damper; through the damping test of wire dampers, the correctness of damping energy calculated theory of wire dampers are proved.

通过输电线自阻尼测试试验，验证了改进后输电线自阻尼计算公式的合理性；通过防振锤不同安装位置时的消振试验，间接验证了优化后的防振锤安装位置计算方法的科学性；通过阻尼线的消振试验，证明了阻尼线耗能计算理论的正确性。

The calculated free vibration frequencies and mode shapes of the whole structural model compare well with measured values. The influences of the various supporting conditions upon the frequencies of the trashrack and the free vibration characteristics of the single rack bars were then studied.

对栅架整体结构模型的自振频率和振型进行了量测，并与数值计算结果作了对比，二者基本吻合，说明成果是可靠的；此外，还对栅架支承条件对拦污栅自振频率的影响以及单根栅条的自振频率特性进行了探讨。

The adding of mineral admixtures and high performance water reducer is the key factor of preparing self-compacting concrete, especially high strength and extra strength self-compacting concrete. Mineral admixtures have unsuperseded advantages in improving the workability and durability of self-compacting concrete.

加入优质矿物掺合料及高效减水剂是配制免振捣高性能混凝土特别是高强超高强免振捣混凝土的技术关键所在，由于优质矿物掺合料的&微集料效应&、&火山灰效应&、&滚珠效应&，使其在改善免振捣混凝土工作性，提高免振捣混凝土耐久性方面发挥了不可替代的作用。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷