子午环

Utilizing the latitudinal mean ot upper meridional wind of 1950 given by Buch and Starr and White, mean meridional circulation has been studied.

本文利用了Buch和Starr与White所计算的1950年各纬度上空的平均经向风速，绘制了子午面上的平均环流(全年：图1，冬季：图2，夏季：图3)，图中显示出三个环型，低纬度和高纬度的两个正环型与中纬度的逆环型。

In order to control the flow separation by reducing the diffusion factor and enlarging the diameter of inner circle, the meridian plane profile of the return channel was redesigned, which is achieved by substituting arbitrary curve for the circle with no change of the axial length of the stage. Bezier curve with eight parameters was chose to describe the shape of meridian plane profile, and the optimization of the meridian plane profile was implemented combining back-propagation neural network with genetic algorithm.

改进的主要思路是减小弯道前半部分通道的扩压度，并同时加大弯道出口内侧的转弯半径，主要做法是在不增加整级轴向尺寸的前提下，用任意曲线取代传统弯道的同心圆环结构，给定弯道回流器子午型线的外侧型线，采用Bezier曲线对内侧型线的2段曲线进行参数化描述，利用遗传算法和反向传播(back-propagation，BP)神经网络相结合的方法对内侧型线进行优化，得到新的弯道回流器子午型线。

The key technology of this method is to quickly converge the sensitive axes of the mechanical gyroscope to the intersection line of the meridional plane and the horizontal plane based on the principle of gyroscope compass, to isolate payload from platform disturbance with the gyroscope and two degrees of freedom gimbals, to obtain the attitude angle of the platform by electro-optical sensor on the gimbals, and to make the sight slaved to the sensitive axes of the gyroscope to realize the indirect stabilization.

利用陀螺罗经原理，使机械陀螺的敏感轴快速收敛于子午面和水平面的交线上，并借助陀螺定轴性和2自由度环架，使陀螺隔离运动载体的扰动；通过环架上的光电传感器测出运动载体的姿态角，使观瞄镜的瞄准线随动于陀螺的敏感轴，实现间接稳定。

By circumferential and meridional pressure correlation study, we point out that, the correlation between windward area and leeward area is very small.

计算了风压沿环向和子午向的相关性系数，发现迎风区与尾流区内的各点风压相关性很低。

After the functions and characteristics of the 9 Reticon signals are anatomized, a new method used to process these Reticon signals is presented, which consists of a reticle/slit image searching algorithm, a self-estimation filtering algorithm and a single wave centering algorithm. The method provides the high precision measurement of the LLMC with a fundamental condition.

在仔细分析了低纬子午环上九路Reticon信号的特点之后，作者提出了处理这九路Reticon信号的新方法，它包括刻线/狭缝像的搜索算法、自估计滤波算法和单波峰定心算法，该方法为低纬子午环进行高精度测量提供了一个最基本的保证。

Making use of structural characteristics of the Lower Latitude Meridian Circle and the error theory of this instrument, we have developed a method used to measure directly instantaneous atmospheric refraction, and moreover built a local observational astronomical refraction model toward the east, south, west and north of Yunnan observatory that is classified according to the star's spectral type.

阐述了云南天文台探讨出的利用低纬子午环的观测原理，在不同方向和不同天顶距直接测定瞬时大气折射值的一套方法，并给出了用实测数据在东、南、西、北4个方向建立的按恒星光谱型分类的大气折射实测模型。

Since there are some disadvantages, such as magnitudes, reference systems and difficulties in observing an asteroid during its motion in its whole orbit, etc., when the asteroid is observed simply by means of the meridian or photograph methods, a new method for observing asteroids with a lower latitude meridian circle and a CCD measuring device is proposed according to the conditions of the geographic latitude of the Yunnan Observatory which can be used to observe the whole orbit of an asteroid.

考虑到单纯用子午方法或照相方法对小行星进行观测存在着因星等、定标星系统，以及难于在小行星运行全轨道上进行观测等方面的不利因素，在本文中，根据云南天文台能观测小行星全轨道的地理纬度条件，提出利用低纬子午环与CCD测量装置相配合，并利用低纬子午环直接提供的定标星，在一个统一的基本仪器系统中，通过对小行星在全轨道上均匀分布的观测，获得高精度的小行星观测资料，以便得到更准确的星表零点改正。

On the special structure of the Lower Latitude Meridian Circle and the practice of determining astronomical refraction in Yunnan observatory,a new method for improving the correction accuracy of the atmo- spheric refraction delay is proposed:the determined data of the astronomical atmospheric refraction values with different azimuths are utilized to find the refractivity and the param- eters of mapping functions for modeling the atmospheric refraction delay correction,which changes with the observing stations and azimuths.

根据云南天文台低纬子午环的特殊结构，和测定大气折射的实践，提出了提高折射延迟改正精度的新方法，即：利用各观测站不同方位从天顶附近直到低地平高度角的天文大气折射实测数据，求解得到折射率差和映射函数的参数，从而建立随测站和随方位而异的大气折射延迟改正模型。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。