查询词典 zenith

As one of the most often used mountings, the altazimuth mounting satellite tracker has a blind area near the zenith because of the very high azimuth angular velocity, as a result, discontinuous observing data are caused. As for those fast flying satellites, this kind of blind area is very significant because it causes difficulties in precisely determining the satellites' orbits.

作为最常用的一种机架，采用地平式机架的人卫跟踪仪在观测天顶附近区域的目标时，由于方位转速过大而不能连续观测，存在一个固有的天顶盲区，特别是对飞行速度较快的近地卫星，这个盲区的影响是相当大的。

In the process of radiation calculation in the real atmosphere, the exactly integrating over the zenith angle is computationally expensive, and thus the diffusivity factor is used to approximate to the integration over the zenith angle.

在大气辐射传输计算过程，对天顶角的精确积分非常费时，可以通过漫射因子近似方法进行简化处理。

The basic principle is based on spherical astronomy and elementary geometry of the trajectory mapping method based on the observation of a celestial body zenith distance, then the ship is located in order to sing the next point as the center of this satellite zenith distance of the ship's position as the radius of the circle, observing the same two objects, or objects at different times of the two observations, we can get two ship's position round, then the ship must have been a point of intersection of two ship's position on the circle.

其基本原理是建立在球面天文学和初等几何中的轨迹作图法基础上的，观测一个天体的天顶距，则航船就位于以星下点为圆心，此星天顶距为半径的船位圆上，观测两个天体或者不同时间同一天体的两个观测值，就可以得到两个船位圆，则航船一定在两个船位圆的一个交点上。

To get the observer's Lat.and Long.just by pressing a button without the sea horizon to turn to,we should know clearly the relationship between the accuracy of zenith distance observed and the accuracy of a position fixed,the causes of the errors of zenith distance observed,what accuracy of zenith distance observed could be obtained and what accuracy standard should be used.

要在无水天线测天时一按按钮就可定出较精确的船位经纬度，必须弄清天体顶距测量精度对定位精度的影响，弄清顶距测量误差产生的原因，可达到的精度及选用适当的精度标准。

The results indicate that the distribution of the solar zenith distance versus the occurring probability of earthquakes is quite consistent with the lunar case, and the case for small earthquakes is different from the larger earthquakes. The latter is mainly clustered at 0oand l80o of the zenith distance, and consistent with the distribution of the absolute value of the solar tide forces, while the former are clustered at 60o and l2Oo.

统计发现：地震的太阳天顶距地震频度和月球天顶距地震频度分布表现出一致的规律性，且较大地震和小地震的活动规律不同，较大地震丛集发生在太阳天顶距0°和180°附近，与地面引潮力的绝对值分布有较好的一致性；而小地震多丛集在太阳天顶距60°和120°附近。

Based on the ISC earthquake catalogue data, according to the orbit equations of two-body-problem and the perturbation theory of celestial mechanics, we could determine the projection pole of the sun, and thus calculate the zenith distance from the sun to the epicenter. After calculating all the earthquakes on their zenith distances, we could get the distribution of the solar zenith distance versus the occurring probability of earthquakes.

基于ISC地震记录，利用天体动力学中二体问题的轨道方程和摄动理论，确定发震时刻太阳在地面的投影点位置，并进一步计算出太阳相对震中的地心天顶距，将地震按天顶距的大小进行统计，得到地震的太阳天顶距地震频度分布。

Zenith telescope天顶仪It felt as if we had traveled from nadir to zenith.

感觉上我们好像已从天底走到了天顶。

It is very important to research on the problem of the zenith blind zone and correlative technology in theory and practice. Research also leads to some di...更多rections for future investigation.In the dissertation the development actuality of correlative tracking technology around the zenith are summarized by the numbers.

本文以测星精密光电望远镜和地基激光反卫星跟踪望远镜项目为课题背景，在系统的总结国内外过天项目标跟踪技术发展现状的基础上，归纳出三种解决方案：方位轴倾斜方法、增设次俯仰轴方法、程序引导方法。

Modern and practical astronomy was developed in the 18th century, and successively from the theoretical and practical solution to the Sino-satellite instrument measuring time, too Seoul Scott multi-satellite measurements such as latitude, as well as simultaneous determination of longitude and latitude Supreme Court means the emergence of theodolite, contour instrument, the satellite instrument, zenith instrument, photographic zenith tube, sextant and other useful astronomical instruments, the most commonly used is the optical theodolite .20 century, all-round practical field of astronomy 60 years after the emergence of new technologies, such as satellite Dhoop Le observation and satellite laser ranging, not only the accuracy of more than optical observations, but also greatly improved operating speed, and can provide direct point of geocentric coordinates of the ground.

现代实用天文学是18世纪发展起来的，先后从理论和实践上解决了中星仪测时、太尔各特测纬以及多星等高法同时测定经度和纬度的方法，出现了经纬仪、等高仪、中星仪、天顶仪、照相天顶筒、六分仪等实用天文学仪器，最常用的是光学全能经纬仪。20世纪60年代以后实用天文学领域出现了崭新的技术，如人造卫星多普勒观测和人卫激光测距，不但精度超过光学观测，而且作业速度大大提高，并能直接提供地面点的地心坐标。

Starting with the zenith, a series of star fields at different altitude are observed by a telescope with larger field of view, the derivatives of various orders are calculated at different zenith distances, and finally the observational atmospheric refraction can be obtained by numerical integration.

利用一台较大视场的望远镜从天顶开始，在不同高度上对星空作一系列观测，计算不同天顶距处大气折射函数的各阶导数，最后经数值积分可给出大气折射实测值。

Objective To investigate the effects of interleukin-1 β converting enzyme gene on the biologic characteristics of ovarian cancer cells.

目的 探讨白细胞介素-1 β转换酶的表达，对卵巢癌细胞生物学特性的影响。

Campylobacter: This illness is the most commonly identified cause of diarrheal illness in the world.

弯曲：这种病是最常见的原因查明腹泻病，在世界上。