查询词典 antenna

The dissertation includes the work as follows: Firstly, we present a random graph model with spatial reuse for a dense MANET which using directional antennas. The analytic formula of several important performance parameters for the MANET are obtained under the DSR routing protocol, such as the average flooding distance, the probability generating function of the flooding distance, the probability of a flooding route to be symmetrically valid, the average time to find a symmetrically valid route and the cost to successfully route a data packet to its destination. We compare the two models with spatial reuse and without spatial reuse by evaluating these parameters. It is shown that the spatial reuse model is much more effcctive in terms of the performance of the dense network with directional antenna, because the bigger is the degree of spatial reuse, the smaller is the average flooding distance.

在定向天线技术的支持下，建立了移动自组网络空间可重用的贝努利随机图模型，获得了DSR路由协议下平均泛洪距离的解析公式和泛洪距离的概率母函数：给出了有效对称路由概率、发现有效路由平均时间、成功路由代价等关键性能参数的解析分析；在网络性能参数定量分析的基础上，对空间可重用和无重用的网络进行了比较分析，结果显示空间重用度增大，则平均泛洪距离、路由发现时延、网络代价减少。

"A small knob or head-shaped part , such as a protuberance of a bone or the tip of an insect's antenna."

一小块球状突出物或头状部分，如一根骨头的突起或一个昆虫的触角的顶端。

Using the finitedifference timedomain electromagnetic method and c language program in the matlab software,the spatial electromagnetic field distribution radiation of photoconductive dipole antenna is calculated and displayed on the computer in a pseudocolor graph.

研究了光电导天线产生太赫兹波的辐射特性，利用麦克斯韦方程及其边界条件，计算了近远场的电场强度；采用电磁波时域有限差分方法，在Matlab系统软件中，用C语言编写程序计算光电导偶极天线的辐射太赫兹波的空间电磁场分布，并在计算机上以伪彩色图形显示，这种电磁场的可视化结果为天线的设计和改进提供了直观的物理依据。

This research process the ionosphere-free triple-differenced carrier phase observation which consist of double frequency GPS observations from the GPS receiver carried on the CHAMP and 40 IGS tracking stations. Besides, the tropospheric correction model, solid earth tide correction, mass center correction of the satellite, earth rotation correction and antenna phase center correction are incorporated. Finally, determine the satellite short-arc orbit with the pure geometry, kinematic, method.

本研究利用CHAMP卫星上装载之GPS接收器所接收之双频观测量与地面上40个IGS追踪站组成三次差分无电离层观测量，并改正观测量中之对流层误差、固体潮误差、质量中心改正、地球自转、天线相位中心偏差等误差量，以纯几何之动态法求定低轨卫星之短弧轨道位置。

With a frightful qualm, I turned, and I saw that I had grasped the antenna of another monster crab that stood just behind me.

我感到一阵可怕的恶心，转过身来，发现我抓住了正爬在我身后的另一只巨蟹的触须。

By using the quantum jump approach, we show that the efficiency depends intimately on the quantum interference among states in which the excitation is localized on individual sites in the antenna.

补充：通常情况下要在室温下实现宏观量子相干很难，但考虑到光合反应中电子转移过程的时间在飞秒量级，在超短时间内维持室温宏观量子相干或许是可行的。

This paper introduces the structural design of various typical medium-wave radiating antenna which have been constructed in our country.

本文较系统地介绍了我国已建成的各种典型中波发射天线的结构设计，可供相关的工程设计人员参考。

The radio beam can be thought of as a light beam. The reading antenna illuminates a well-defined zone.

这种超高频率电波类似光源自动照射的范围，具有区域性。

An antenna array that is truly smart would be able to aim a radio beam directly at a mobile user instead of choosing a beam that comes relatively close.

一个真正聪明的阵列天线，必须能够直接把波束瞄准行动用户，而不是选用与用户较为接近的波束。

It is called a radio telescope because a radio antenna is used to observe radio waves emitted by astronomical sources.

它被称为射电望远镜，因为收音机的天线是用来观察天文活动所排放的无线电波。

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