查询词典 zenith distance

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。

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。

In order to improve the monitoring precision and resolution of tropospheric zenith delay, the hybrid approach, using a batch least squares estimator but parameterizing the zenith delay by a linear spline with knots at 30-minute intervals and treating the knots as a Gauss-Markov process, is employed to deal with the tropospheric zenith delay.

为了提高对流层天顶延迟的监测精度和分辨率，我们采用了分段的参数估计和随机过程相结合的估算方法来处理对流层延迟，由此获得了分辨率分别为2 h和30 min，精度好于1 cm的天顶延迟量。

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。

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。

Isomap is one of the representative techniques of nonlinear dimensionality reduction.It extends classical multidimensional scaling by considering approximate geodesic distance. However,Isomap is sensitive to noise because the approximate geodesic distance is constructed on the basis of Euclidean distance. In this paper,a kernel-induced distance metric defined in the feature space is introduced instead of the Euclidean distance to evaluate the geodesic distance and construct the corresponding neighborhood graph.

采用核方法在特征空间推导出一类异于欧氏距离的新度量，代替等度规特征映射中的对噪声敏感的欧式距离，用新度量构造测地距离和相应的最小近邻图，提高Isomap算法的抗噪声能力。

Apparently, the results is determined extremely by theoretical algorithm. In 147 zinc-finger-containing genes, 50nt identity sequences were extracted. The results hint that 15 genes may related to block evolution. we analyzed the phylogenetic map of these 15 genes by uncorrected distance, Jukes Cantor distance, Tamura distance, Tajima-Nei distance, Jin-Nei distance or Kimura distance correction, but we found no satisfied result according to the block exchange pattern mentioned before. Introducing Bootstrap test to assistant correction, an comparatively perfect map was drown by Neighbor Joining method.

以147个含锌指基因为模板，我们搜索了其中的50nt一致序列作为板块式进化的核心，获得15个相关基因，应用无校正距离、Jukes Cantor校正距离、Tamura校正距离、Tajima-Nei校正距离、Jin-Nei校正距离和Kimura校正距离等分析了他们之间的进化关系，结果与已知的板块交换模式吻合度较差，引入靴带检验对Jukes Cantor校正距离结果进行统计学校正，并重新用Neighbor Joining方法绘制进化图，结果可靠性大大提高。

However, after I came to understand distance education more deeply, I find that network distance continuation education has many advantages. Firstly, it breaks through the limitation of time and distance. It enables the students all over the country to get instructed from those top level teachers, take the most advanced teaching method, and enjoy richer education information resource. Secondly, it profits in extending the teaching scope, providing more education chances and more flexible way of learning, which make it possible to let more people accept education. Thirdly, the modern network distance continuation, which is based on information, offers a good space-time platform for a lifelong learning. At last, the modern network distance continuation makes students to focus on self study, which help them to fully develop their proactivity, intuitivity and creativity. For the four reasons mentioned above, finally, I chose network distance continuation education as the way of my further education.

但是，经过深入了解之后，发现远程网络继续教育是有很多的优势的，第一，它可以突破时空的限制，使全国各地的学生都能接受一流水平教师的教导，接受最先进的教学方法，享有更丰富的教学信息资源；第二，有利于扩大教学规模，提供更多的学习机会和更灵活的学习方式，使更多的人可以接受教育；第三，以基于信息技术的现代远程网络继续教育，为终生学习的实现提供了时空平台，为人们提供更多开展的实施终身学习的机会；第四，现代远程网络继续教育以学习者自学为主，充分发挥学习者自主学习的主动性、积极性及创造性，综合以上四点，我最终选择远程网络继续教育作为我继续学习的途径。

According to the engineering practice, the theoretical basis and method that survey directly the horizontal distance and height difference by the total station system as fourth grade and below fourth grade control network are put forward instead of surveying slant distance and zenith distance.

摘要根据工程实践，提出了用全站仪直接测量平距、高差来代替测斜距、天顶距作四等及四等以下控制网测量的理论依据和方法，并以张河湾抽水蓄能电站施工控制网为例进行了比较计算。

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。

Green function defined inphase space differs from one in coordinate space by its struc-ture which exhibits nonlocatity in coordinates and oscillatorybehavior with respect to momenta.

在相空间中定义的Green函数不同于通常坐标空间的Green函数，在结构上显示出对坐标的高度非局域性，而对动量则显示出振荡行为。

The upper front part of a saddle;a saddlebow.

前鞍桥马鞍前面的上部分；前鞍桥