共查询到19条相似文献，搜索用时 93 毫秒
1.
主要介绍利用Microsoft Visual Basic.NET编写的地形图分幅编号查询与面积计算程序。通过该程序,根据经纬度坐标或高斯坐标,可查询该点所在各种基本比例尺下的图幅编号、西南图廓点的经纬度坐标以及在不同坐标系下的图幅面积。 相似文献
2.
地形图图幅编号的自动查询与检索 总被引：9，自引：2，他引：7
通过编写程序,可对地形图图幅编号进行自动查询与检索。若给出某点的经纬度坐标,可自动查询该点所在的指定比例尺图幅编号,若给出某区的经纬度坐标范围,可自动检索该区指定比例尺所有图幅编号。 相似文献
3.
4.
5.
6.
目前在测绘工作中,由某一地图图幅国际分幅法编号（以下简称图号）换算为所在的经纬度,或由某一图幅的经纬度求其相应的图号,其方法颇繁,容易产生错误。本文从实际使用方便出发,探求一个互相换算的查 相似文献
7.
基于Web的地形图查询信息系统设计与开发 总被引：2，自引：0，他引：2
目前的地形图查询系统存在着依赖GIS二次开发平台、功能不够全面和不能实现网络查询等不足.基于Visual Basic.NET开发平台,设计实现了一个功能较完善的网络地形图查询信息系统,实现了单点图幅查询、矩形区域查询以及任意区域图幅查询功能. 相似文献
8.
9.
基于点与多边形关系的地形图图幅查询系统实现 总被引：1，自引：0，他引：1
利用点与多边形关系判定中改进的射线算法,实现区域多边形范围内地形图图幅号的自动查询和输出功能,同其他方法相比,该方法具有易于理解、稳定可靠,通用性强的特点和优势. 相似文献
10.
天津90图幅号算法入手,建立了一个基于ObjectArx2004的二次开发程序。通过加载ARX文件到Auto-CAD环境,能够实时、准确地计算出给定范围的图幅号。为此,对实际作业中的点、线、面和图幅号对象进行抽象,设计了新的基于面的图幅号算法,实现了AutoCAD环境下方便获取天津90图幅号。 相似文献
11.
《测量评论》2013,45(60):220-221
AbstractThe problem of computing marginal scales of latitude and longitude on a rectangular map on the Transverse Mercator projection, where the sheet boundaries are projection co-ordinate lines, may be solved in various ways. A simple method is to compute the latitudes and longitudes of the four corners of the sheet, and then, assuming a constant scale, to interpolate the parallels and meridians between these corner values. Although it is probably sufficiently accurate for practical purposes, this method is not precise. It is not difficult to adapt the fundamental formulce of the projection to give a direct solution of the problem. 相似文献
12.
Summary According to the plate tectonic theory of Le Pichon [1968] we summarized the absolute values of the angular rate of rotation
of the Eurasia and America plates determined by astronomical latitude observations. The authors then tried to use the data
of longitude observation so far available to emphasize the existence of similar crust movements. The analysis of longitude
data has shown the minor homogeneity of these astronomical observations especially as far as the observations obtained by
means of PZT are concerned. By using particularly accurate observational data [Torao & Okasahi, 1965, 1969] the data of longitude
variations confirm the existence of movements in the earth’s crust, exactly equal to those deduced by the analysis of latitude
observations and in agreement with the results of geophysical measurements. 相似文献
13.
Seasonal and secular positional variations at eight co-located GPS and VLBI stations 总被引：2，自引：0，他引：2
Time series of daily position solutions at eight co-located GPS and VLBI stations are used to assess the frequency features in the solutions over various time-scales. This study shows that there are seasonal and inter-annual signals in all three coordinate components of the GPS and VLBI solutions. The power and frequency of the signals vary with time, the station considered and the coordinate components, and between the GPS and VLBI solutions. In general, the magnitudes of the signals in the horizontal coordinate components (latitude and longitude) are weaker than those in the height component. The weighted means of the estimated annual amplitudes from the eight GPS stations are, respectively, 1.0, 0.8 and 3.6 mm for the latitude, longitude and height components, and are, respectively, 1.5, 0.7 and 2.2 mm for the VLBI solutions. The phases of the annual signals estimated from the GPS and VLBI solutions are consistent for most of the co-located stations. The seasonal signals estimated from the VLBI solutions are, in general, more stable than those estimated from the GPS solutions. Fluctuations at inter-annual time-scales are also found in the series. The inter-annual fluctuations are up to ∼5 mm for the latitude and longitude components, and up to ∼10 mm for the height component. The effects of the seasonal and inter-annual variations on the estimated linear rates of movement of the stations are also evaluated. 相似文献
14.
Computing geodetic coordinates from geocentric coordinates 总被引：1，自引：1，他引：0
H. Vermeille 《Journal of Geodesy》2004,78(1-2):94-95
A closed-form algebraic method to transform geocentric coordinates to geodetic coordinates has previously been proposed. The validity domain of latitude and height formulae in the vicinity of the Earths core is specified. A new expression of longitude is proposed, excluding indetermination and sensitivity to round-off error around the ±180 degrees longitude discontinuity. 相似文献
15.
16.
17.
CHENJunyong DANGYamin 《地球空间信息科学学报》2005,8(2):79-84
If a geocentric 3D coordinate system is adopted in China to replace 2D non-geocentric coordinate system, the coordinates of the surface points will be changed accordingly. The influences on the current maps of China, especially the topographic maps, are discussed due to the replacement of the coordinate systems. Taking the replacement of Xi‘an 80 coordinate system by GRS80 for a numerical example, this paper analyzes the changes of latitude, longitude, Gauss plane coordinates of the surface points, as well as the orientation and the length changes between the points on the map, including the changes of map border lines and sheet corner points. 相似文献
18.
19.
R. H. Rapp 《Journal of Geodesy》1967,41(1):55-65
In support of requirements for the U.S. Air Force Cambridge Research Laboratories, gravity anomalies have been upward continued
to several elevations in different areas of the United States. One area was 340 to 400 N in latitude and 960 to 1030 W in longitude, generally called the Oklahoma area. The computations proceeded from 26, 032 point anomalies to the prediction
of mean anomalies in 14, 704, 2.5′×2.5′ blocks and 9,284, 5′×5′ blocks. These anomalies were upward continued along 28 profiles
at 5′ intervals for every 30′ in latitude and longitude. These anomalies at elevations were meaned in various patterns to
form mean 30′×30″, 10×10, 50×50 blocks. Comparisons were then made to the corresponding ground values. The results of these comparisons lead to practical
recommendations on the arrangement of flight profiles in airborne gravimetry. 相似文献