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1.
工程测量学的发展评述   总被引:20,自引:3,他引:17  
本文对工程测量学重新进行了定义,指出了该学科的地位和研究应用领域,阐述了工程测量学领域通用和专用仪器的发展,在理论方法发展方面,重点对平差理论、工程网优化设计、就业菜观测数据处理方法进行了归纳和总结。扼要地叙述了大型特种精密工程测量在国内外的发展情况。结合科研和开发实践,简介了地面控制与施工测量工程内外业数据处理一体化自动化系统--科傻系统。最后展望了21世纪工程测量学若干发展方向。  相似文献   

2.
基于参考站的GPS单点观测在城市及工程测量中的应用探讨   总被引:1,自引:0,他引:1  
熊远社  陈现春 《四川测绘》2003,26(4):173-175
本文对基于连续运行参考站(跟踪站)的高精度GPS单点观测模式及其特点进行了简要的介绍,并对该方法用于城市及工程测量的可行性进行了分析和探讨。最后通过生产实例,展示了该方法在城市及工程GPS测量应用中所具有的一些优点。  相似文献   

3.
管理者和设计得对三维目标模型的需求日益增加,尤其是在建筑环境下,装在一台全站仪上的数字相机能够准确地获取建筑物的立面和近似立面。本文作者设计出了一个视经纬仪模型,并指出了将来需要研究的问题。  相似文献   

4.
Wrob.  BP 周月琴 《测绘译丛》1993,(6):21-27,20
本文概括了从解析摄影测量到数字摄影测量的进展,部分地考虑了所采用的方法,但主要强调数学和物理原理。解析摄影测量的原始信息量测数据是影像坐标,而数字摄影测量原始信息量测数据是数字影像灰度值。从这两种原始数据的本质可以明显地看出解析摄影测量与数字摄影测量的基本区别。对这两种技术,比较了它们的高斯-马尔柯夫估计过程,提出了影像空间和目标空间之间的相互关系;对辐射的考虑比以前起了更重要的作用。数字摄影测量  相似文献   

5.
扬州体育场将承办世界体育赛事,对场内跑道各项指标精度要求较高。本文介绍了扬州体育场400m跑道长度测量、基准点检查以及坡度测量的具体测量方法,该方法引进了TM30测量机器人和DINI03数字水准仪,对跑道划线和坡度进行了高精度观测,将观测数据导入计算机中,经EXCEL和绘图软件CASS处理后,做出体育场跑道划线误差分析及坡度误差分析,此方法验证了测量机器人TM30在体育场高精度划线中的高效应用,验证了扬州体育场跑道划线误差较小,坡度变化符合国家体育赛场的要求。  相似文献   

6.
航空矢量重力测量误差模型的建立及初步分析   总被引:1,自引:0,他引:1  
航空矢量重力测量的目的是确定沿飞行轨迹的整个重力扰动矢量。基于INS/GPS的矢量重力测量,重力扰动矢量确定精度直接受INS测量误差和GPS观测误差的影响。INS测量误差主要包括姿态测量误差和加速度计误差。影响GPS导出加速度精度的主要误差是多路径效应和测量噪声。本文建立了航空矢量重力测量的基本误差模型,据此,对上述各项误差的成因,性质及消除措施作了初步探讨,其中重点分析了GPS确定加速度的误差模  相似文献   

7.
本文结合上海浦东国际金融大厦工程阐述了高层建筑物钢结构施工安装过程中的测量工作,对引点产生的误差采用伪逆自同网平差方法进行处理,提高了控制点的精度,开发了一套由便携机和全站仪组成的实时钢结构放样测量系统,该系统具有快速,灵活,准确的特点,不仅提高了生产效率,而且达到了对资料计算机化管理。  相似文献   

8.
正余弦法进行井下经纬仪导线非对中测量的探讨及其应用   总被引:3,自引:1,他引:2  
王晖 《测绘通报》2000,(4):20-21
将正余弦原理应用在井下经纬仪导线测量中 ,从而形成了井下经纬仪导线非对中测量的一种方法 ,并应用误差传播定律 ,对最佳图形及其该法所能达到的精度进行了探讨。  相似文献   

9.
刘佳 《北京测绘》2014,(5):92-94
规划监督测量在本市规划、建设和管理中发挥了基础保障的作用.它既是城市建设的基础性工作,同时也是城市建设规划的重要环节.本文将对规划监督测量中灰线验线测量、正负零验线测量、竣工测量三大重点内容进行全方位阐述,并对每个阶段存在的问题及测量重点及进行了解析.  相似文献   

10.
水域测量的有关关键技术   总被引:1,自引:0,他引:1  
姚宜斌 《东北测绘》2000,23(2):34-35
水域测量包括海洋测量,河道测量,水库测量等,本文根据作者自已的实践,提出了水域测量实施及测量成果后处理过程中应注意的有关问题,并对有关的难点提出了解决办法。  相似文献   

11.
 采用Landsat TM数据分析了阿克苏河—塔里木河断面水质污染状况,通过波段的DN值和常规监测数据建立能反映水质状况的 污染物监测模型。结果发现,将2000年常规监测数据代入模型后,与遥感数据的结果基本吻合| 重建阿克苏河—塔里木河的连续水体 污染变化曲线,得出污染物浓度随着远离上游而增加。  相似文献   

12.
本文探讨了制约地图符号设计的内在的基本规律,提出了地图符号的约定性原则和等价性原理。把作为地图符号的物质时象同传输过程中的地图符号区别开来,分析了地图符号的价值及价格,并对内涵地图符号和外延地图符号及其相互关系进行了研究,最后提出了新的地图符号分类原理。  相似文献   

13.
The area around Sataun in the Sirmur district of Himachal Pradesh, India (falling between the rivers Giri and Tons; both tributaries of the Yamuna River) was studied for landslide vulnerability on behalf of the inhabitants. The study was made using extensive remote sensing data (satellite and airborne). It is well supported by field evidence, demographic and infrastructural details and aided by Geographic Information System (GIS) based techniques. Field observations testify that slope, aspect, geology, tectonic planes, drainage, and land use all influence landslides in the region. These parameters were taken into consideration using the statistical approach of landslide hazard zonation. Using the census data of 1991, vulnerability of the populace to the landslide hazard was accessed. As most of the infrastructure in the region is concentrated around population centres, population data alone was used for vulnerability studies.  相似文献   

14.
大地重力学的新进展   总被引:1,自引:1,他引:0  
介绍了当前利用卫星探测地球重力场的技术及其实践,也就是目前采用的高轨卫星追踪低轨卫星技术(hl-SST)、低轨卫星追踪低轨卫星技术(ll-SST)、卫星重力梯度测定技术(SSG),及其相应的正在运行的CHAMP、GRACE、GOCE卫星和考虑发射的GRACEFollow-On卫星。运行的三颗卫星所提供的地球重力场信息不论在精度和分辨率方面都是大地重力学的一个重大进展。介绍了地形数据在构建地球重力场模型中的作用和美国SRTM对全球地形数据的测量。最后介绍了EGM2008与我国已有大陆重力值的比较,平均差值约为11mgal,与我国大陆现有的高程异常值的比较,平均差值为27cm左右。  相似文献   

15.
Comparison between two time points of the same categorical variable for the same study extent can reveal changes among categories over time, such as transitions among land categories. If many categories exist, then analysis can be difficult to interpret. Category aggregation is the procedure that combines two or more categories to create a single broader category. Aggregation can simplify interpretation, and can also influence the sizes and types of changes. Some classifications have an a priori hierarchy to facilitate aggregation, but an a priori aggregation might make researchers blind to important category dynamics. We created an algorithm to aggregate categories in a sequence of steps based on the categories’ behaviors in terms of gross losses and gross gains. The behavior-based algorithm aggregates net gaining categories with net gaining categories and aggregates net losing categories with net losing categories, but never aggregates a net gaining category with a net losing category. The behavior-based algorithm at each step in the sequence maintains net change and maximizes swap change. We present a case study where data from 2001 and 2006 for 64 land categories indicate change on 17% of the study extent. The behavior-based algorithm produces a set of 10 categories that maintains nearly the original amount of change. In contrast, an a priori aggregation produces 10 categories while reducing the change to 9%. We offer a free computer program to perform the behavior-based aggregation.  相似文献   

16.
董群 《现代测绘》2009,32(4):16-19
数字高程模型和数字正射影像是城市基础地理信息的核心载体.两者数据都是连续的地表模型数据.本论文旨在研究建立一个以这两种数据为主体的数据库集成管理系统,并能够提供基本的分析和应用功能,为城市的规划、建设、管理和社会各行业提供完善、优质和高效的地理空间数据服务.论文以宁波市两者数据的建库为例.首先介绍一些有关背景资料;然后详细研究了该系统的设计情况,包括设计的原则、技术路线,数据组织和功能规划;最后进行总结,分析了该系统架构设计的优缺点.  相似文献   

17.
地图是人们生活中不可或缺的一种工具,是国防建设的重要支持。专题图作为地图的一个大类,是以集中表现某种主题内容的地图。如今,根据不同的需要,专题图表现形式繁多。社区详图作为以社区为地图表现范围,以与社区相关信息为主题的专题图首次出现在杭州。本文从地图的分类出发,通过杭州市社区详图的编制等情况,进一步与大家共同探讨社区详图的编制与设计,以及社区详图在日常的生活中所发挥的作用及领域。  相似文献   

18.
王冬滨 《测绘工程》2002,11(4):36-38
DPS具有几何精度高的特点,而RS具有信息量大、现势性强的优点,本文的目的是将两者的优点融合起来,形成DPS与RS的复合产品。研究了融合的理论基础,设计了融合的工艺流程,经过试验得出了令人满意的结果。  相似文献   

19.
Three-dimensional building models are important for various applications, such as disaster management and urban planning. The development of laser scanning sensor technologies has resulted in many different approaches for efficient building model generation using LiDAR data. Despite this effort, generation of these models lacks economical and reliable techniques that fully exploit the advantage of LiDAR data. Therefore, this research aims to develop a framework for fully-automated building model generation by integrating data-driven and model-driven methods using LiDAR datasets.The building model generation starts by employing LiDAR data for building detection and approximate boundary determination. The generated building boundaries are then integrated into a model-based processing strategy because LiDAR derived planes show irregular boundaries due to the nature of LiDAR point acquisition. The focus of the research is generating models for the buildings with right-angled-corners, which can be described with a collection of rectangles under the assumption that the majority of the buildings in urban areas belong to this category. Therefore, by applying the Minimum Bounding Rectangle (MBR) algorithm recursively, the LiDAR boundaries are decomposed into sets of rectangles for further processing. At the same time, the quality of the MBRs is examined to verify that the buildings, from which the boundaries are generated, are buildings with right-angled-corners. The parameters that define the model primitives are adjusted through a model-based boundary fitting procedure using LiDAR boundaries. The level of details in the final Digital Building Model is based on the number of recursions during the MBR processing, which in turn are determined by the LiDAR point density. The model-based boundary fitting improves the quality of the generated boundaries and as seen in experimental results, the quality depends on the average LiDAR point spacing. This research thus develops an approach which not only automates the building model generation, but also achieves the best accuracy of the model while utilizing only LiDAR data.  相似文献   

20.
This paper presents a novel methodological approach to countrywide vegetation mapping. We used green vegetation biomass over the year as captured by coarse resolution hyper-temporal NDVI satellite-imagery, to generate vegetation mapping units at the biome, ecoregion and at the next lower hierarchical level for Namibia, excluding the Zambezi Region. Our method was based on a time series of 15 years of SPOT-VGT-MVC images each representing a specific 10-day period (dekad). The ISODATA unsupervised clustering technique was used to separately create 2–100 NDVI-cluster maps. The optimal number of temporal NDVI-clusters to represent the information on vegetation contained in the imagery was established by divergence separability statistics of all generated NDVI-clusters. The selected map consisted of legend of 81 cluster-specific temporal NDVI-profiles covering each a 15-year period of averaged NDVI data representing all pixels classified to that cluster. Then, by legend-entry using the dekad-medians of all 15 annual repeats, we produced generalized legend-entries without year-specific anomalies for each cluster. Subsequently, a hierarchical cluster analysis of these temporal NDVI-profiles was used to produce a dendrogram that generated grouping options for the 81 legend-entries. Maps with cluster-groups of 8 and 4 legend-entries resulted. The 81-cluster map and its 65 legend-entries vector version have no equivalent in published vegetation maps. The 8 cluster-group map broadly corresponds with published ecoregion level maps and the 4 cluster-group map with the published biome maps in their number of legend units. The published vegetation maps varied considerably from our NDVI-profile maps in the location of mapping unit boundaries. The agreement index between our map and published biome maps ranges from 70−93. For the ecoregion level, the agreement index is much lower, namely 51−75. Our methodological approach showed a considerably higher discretionary power for hierarchical levels and the number of vegetation mapping units than the approaches applied to previously published maps. We recommended an approach to transform our three hyper-temporal NDVI-profiles based legend-entries into more specific vegetation units. This might be accomplished by re-analysis of available, spatially-comprehensive plant species occurrence data.  相似文献   

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