基于Voronoi图的点状目标邻近空间分布测试方法

邻近空间分布测度研究观测点邻近空间中目标的分布规律,是地理分析、环境评价、选址优化等的重要依据。提出了基于Voronoi图的邻近空间分布测度方法。该方法通过观测点的k阶Voronoi邻近关系,动态确定影响观测点的空间目标范围,通过k阶邻近分布指数定量评价观测点邻近空间目标的分布情况,实现了任一观测点邻近空间分布的测度,并将k阶邻近分布指数应用于整体空间目标离散度的测度。最后通过城市楼盘开发与景观保护评价实例说明了该方法的应用前景。     

高速公路沉降观测点的布设

文章针对高速公路进行沉降观测特殊的3项职能问题，阐述了合理布设沉降观测点的重要性，提出了沉降观测点布设原则和步骤，论述了布设观测点过程中所要考虑的因素，总结了布设观测点的方法。     

观测天体方位夹角测定经纬度

观测天体测定经纬度，常用的方法是采用观测天体的天顶距，经过解算求出观测点的位置，作为一种观测方法，我们认为还可以采用观测两天体之间的方位夹角，经过解算求出观测点的位置。现将研究情况介绍如下：     

动线法自动制图

本文从以下七个方面阐述动线法自动制图：①动线法的特点和应用；②数据采集；③以圈形符号表示交叉路口的车流量，以两种不同颜色的“带”表示道路的车流量；④数据结构是采用观测点的编号与观测点的坐标以及道路中心线上点的坐标相结合，观测点编号的输入采用了双重图例式特征码；⑤数据编码采用了按观测点顺序排列；⑥提出一种“平均标准法”的自动分级方法；⑦计算机处理与绘图。     

沉降观测中精密水准测量若干问题的探讨

沉降观测的基本方法，就是以固定水准点的高程为基准，定期对建构筑物的沉降观测点进行水准测量，测定各观测点的高程，从而计算出不同时期观测点的下沉量，当发现对建筑物不利的不均匀沉降时，应及时采取措施，以保证建筑物的安全。     

地面沉降预测方法的探讨

以变形观测点的平均高程作为研究对象,对连云变电所地面沉降规律进行研究.在沉降区域内较均匀地布设一些能反映地面沉降情况的观测点,定期对其进行沉降观测,求得每期观测点的高程值.选用Gompertz曲线模型和Logistic曲线模型进行拟合,建立预测模型,对研究对象进行预测并进行精度评定.通过研究发现,该方法能较好地反映地面整体沉降情况,可以作为研究地面沉降的方法之一.     

高层建筑物沉降观测点的布设

本文针对高层建筑物沉降观测点布设当中所存在的问题,阐述了观测点的布设在沉降观测工作中的重要作用,提出了观测点布设的原则和步骤,论述了布点过程中所要考虑的因素,同时对观测点的合理布设做了系统总结。     

厚松散层煤层开采岩层移动与破坏规律试验研究

利用相似材料模拟试验模拟井下煤层开采,通过在模型上设置测量观测点,采用全站仪测量的方法对观测点进行定期观测,通过对试验观测数据和显现特征分析,总结了厚松散层条件下煤层开采过程中"三带"的发育情况和岩层移动与破坏的一般规律。     

高层建筑物沉降监测与预测方法

高层建筑物沉降变形监测是工程建设中一项十分重要的工作,为了系统地阐述高层建筑物沉降变形监测作业、数据处理及建模预测等方法,文章结合具体工程实例,详细地介绍了其监测作业过程、数据处理方法、图表分析内容以及沉降变形稳定性判别等方法要素,以回归拟合的方法对某代表性观测点监测数据进行了建模与预测分析,并与其它观测点数据进行了预测对比,同时对所建回归模型方程进行了显著性检验、预测区间估算和预测精度分析等,为类似工程实践及数据处理与分析方面提供方法参考。     

基于离散沉降观测的城市地面沉降监测

由于离散观测点沉降数据无法全面反映城市沉降状况,探讨了利用大量离散观测点沉降观测数据进行城市地面沉降监测的方法。设计了利用大量沉降观测数据进行空间插值计算的城市地面沉降监测技术流程;提出了基于交叉验证的城市地面沉降空间内插模型的选取方法;并以某县级市为例,利用该方法对城市地面沉降进行了计算和可视化。结果表明,该方法有效可行,操作性高,具有广泛的应用前景。     

建筑物轴线补点的快速计算方法

在建筑工程施工中,经常遇到建筑物轴线控制桩破坏殆尽的情况,在此情况下,如果初次设点时,在轴线两端的建筑物上弹有墨线,那么根据墨线,在跨轴线两侧任意设置两点,观测四个角度值和两侧两点间距,经解算三角形,即可很快求得,任意设置点至轴线上某点的距离,就能很快将轴线恢复.本文介绍了用Java语言编写在手机上运行的java解算程...     

An application of a summation formula to numerical computation of integrals over the sphere

Summary This paper discusses a method to approximate an integral over the (unit) sphere by a linear combination of the values of the integrand at given points. The main concept of this method is the observation, that on the sphere for each sufficiently smooth function the integral can be expressed by a summation formula. A method is given for optimizing the accuracy of the computation for a given set of sample points for the function being integrated.     

On the combined adjustment of a gravimetrically determined geoid and GPS levelling stations

Summary A new basic geodetic network using the GPS technique is now being set up in France. There will be altogether 1000 benchmarks connected to the French levelling network. Obviously, the GPS levelling points are not dense enough to produce a national levelling reference surface. A gravimetrically determined geoid has therefore been proposed to be used for the interpolation between the GPS levelling points. However, because of long-wavelength errors, we consider that a gravimetric geoid does not have sufficient accuracy. A regression by fitting the gravimetrically determined geoid to the GPS levelling points is generally proposed. Unfortunately, this country-wide geoid fitting work cannot eliminate local deformations in the geoid, which happen in areas where there are errors or shortages of gravity or DTM data. This paper proposes and discusses a combined adjustment method. The principle is to divide up the geoid into small pieces and then to adjust them to the GPS levelling points locally with constraint conditions for the common points of the adjacent pieces. In order to benefit from the advantages of the high resolution and high relative accuracy of the gravimetric geoid, as well as the high absolute accuracy of the GPS levelling points, we establish respectively a relative observation equation for the difference of the gravimetric geoid undulation and an absolute observation equation for the GPS levelling points. Finally, we adjust the observation equations as a whole. Several global and local systematic errors are also taken into account and some special cases, such as adjustment in groups and blunder detection, are also discussed.     

顾及模糊逻辑关系的稳健估计

首先给出了标准化残差受粗差污染的隶属函数，进而导出了观测误差与残差之间的模糊逻辑关系，以及观测误差属于粗差的隶属函数。最后提出了顾及模糊逻辑关系的稳健估计算法。计算结果表明，顾及模糊逻辑关系的稳健估计能有效地抵制粗差的影响，并能正确地定位粗差     

GIS叠置前后同名点元的方差估计

定义了同名坐标观测值矩阵概念，建立了多层叠置同名观测值的多元分析模型，导出了同名点元叠置前后位置方差的一般估计式     

Error modelling,calibration and analysis of an AM–CW terrestrial laser scanner system

A rigorous method for terrestrial laser scanner self-calibration using a network of signalised points is presented. Exterior orientation, object point co-ordinates and additional parameters are estimated simultaneously by free network adjustment. Spherical co-ordinate observation equations are augmented with a set of additional parameters that model systematic errors in range, horizontal direction and elevation angle. The error models include both physically interpretable and empirically identified components. Though the focus is on one particular make and model of AM–CW scanner system, the Faro 880, the mathematical models are formulated in a general framework so their application to other instruments only requires selection of an appropriate set of additional parameters. Results from controlled testing show that significant improvement is achieved by using the proposed model in terms of both reducing the magnitude of observational residuals as well as the three-dimensional positioning accuracy of signalised points. Ten self-calibration datasets captured over the course of 13 months are used to examine short- and long-term additional parameter stability via standard hypothesis testing techniques. Detailed investigations into correlation mechanisms between model parameters accompany the self-calibration solution analyses. Other contributions include an observation model for incorporation of integrated inclinometer observations into the self-calibration solution and an effective a priori outlier removal method. The benefit of the former is demonstrated to be reduced correlation between exterior orientation and additional parameters, even if inclinometer precision is low. The latter is arrived at by detailed analysis of the influence of incidence angle on range.     

基于数理统计方法搜索GPS所有异步环

异步环是GPS基线质量检查的重要内容,以便于发现解算粗差,评估GPS平差的质量及精度。利用数理统计的方法,通过GPS测站点在不同时段的重复情况,利用重复点作为异步环搜索的起始点,利用树形搜索的方法判断重复点之间能否构成异步环,在此基础上从GPS基线向量中抓取基线组成异步环,可以快速、无遗漏地搜索出所有的异步环。通过实例验证,取得了很好的效果。     

基于BDS三频信号的大变形提取算法研究

提出了一种利用北斗卫星导航系统(BDS)三频载波相位信号提取大变形量的单历元算法.该算法基于监测点变形前坐标,采用BDS三频信号构建的超宽巷组合利用无整周问题的数据处理策略求取变形粗略值,通过宽巷及L1原始观测值逐步精化求得精确的变形信息.采用变形监测试验平台的一组实测变形数据进行测试,验证了本文算法的可行性.     

三角高程测距导线垂直角测回数的思考

目前四等三角高程测距导线采用规范不同,测回数也不一样.随着仪器设备精度的提高,达到规范要求的精度,就不需要测量这么多测回数,比如,四等三角高程导线垂直角测回数可以减少到两个测回,同样可以满足四等三角高程测距导线的精度,并且可以减少部分工作量.     

工作基点的位移对观测点的影响分析

在基坑变形监测工作中,受场地条件的限制,工作基点往往只能埋设在基坑边相对稳定的地方,因此,工作基点也会产生位移。针对在施工现场进行变形观测时工作基点易于发生变动的情况,分析和讨论了工作基点位移的确定以及其位移给观测点带来的影响,提出相应的修正方法,并结合工程实例进行了分析。