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数字摄影测量,应用计算机技术、数字影像处理、影像匹配、模式识别等理论与方法,以计算机视觉代替人眼的立体观测,其产品与中间数据的记录以及处理的原始资料均是数字的,较之常规的(传统的)数字产品的生产方法,具有自动化程度高、速度快、成果多样化等优点。两次外业和两次内业,是∶地形图数字摄影测量的主要作业流程,第二次外业调绘作为1500数字摄影测量的主要外业工作与常规调绘方法有一定的区别。∶地形图数字摄影测量适合于1500大面积数字化测图。 相似文献
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本文以聊城市为例,在"数字聊城地理空间构榘建设与应用示范项目"的支持下,详细介绍了正射影像图的制作过程及注意事项,为今后航测正射影像的生产制作提供了方法与依据.随着航空摄影技术的发展与普及,大比例尺正射影像图以其丰富的内容,清晰直观的效果一步步丰富传统地形图;以正射影像为底图的航测线划调查图大大提高了外业调绘的效率及野外补测的精度. 相似文献
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数字摄影测量，应用计算机技术、数字影像处理、 影像匹配、模式识别等理论与方法，以计算机视觉代替人眼的立体观测，其产品与中间数据的记录以及处理的原始资料均是数字的，较之常规的（传统的）数字产品的主要方法，具有自动化程度高、速度快、成果多样化等优点。两次作业和两次内业，是1：500地形图数字摄影测量的主要作业流程,第二次外业调绘作为数字摄影测量的主要外业工作是常规调绘方法有一定的区别。1：500地形图数字摄影测量适合于大面积数字化测图。 相似文献
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在基于ArcGIS模型处理1∶5000专题地理信息数据过程中,数据的批量面擦除、批量数据整合和裁切、数据属性一致性检查、数据格式转换到外业调绘平板是生产过程中遇到的主要问题,为了提高作业效率,利用ArcGIS模型构建器对专题地理数据处理程序进行了研究。本文详细介绍了主要程序的关键技术和在实际应用中取得的较好效果。 相似文献
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机载高分辨率In SAR技术作为一种新的技术手段,被广泛应用于地形测绘、资源调查及灾害监测等方面。机载In SAR影像不同于光学航空摄影,原有的像片调绘方法已不适用于地物的定性和定位。依据机载SAR成像机理,探讨了形状、色调、阴影等SAR影像直观特征对地物空间的对应关系及判读方法,并对地形起伏、地物高度、叠掩、阴影等引起的定位误差进行分析,提出了提高准确定位的措施。在某40km2的外业调绘项目中,其调绘成果经后期实测数据的精度验证,调绘成果定位中误差为0.87m,满足国家规范要求。 相似文献
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在工程地质调绘中引入室内外协同作业法,并根据“室内虚拟地调—室外调绘核查—室内资料整理”三步走的标准业务流程,基于GIS平台开发适用于前述方法的网页端、桌面端、移动端与服务器端应用系统,研究多数据融合、区域地质图剖切、数字化产状量测、数字化采集模板配置与多端数据协同技术,革新地质调绘作业模式并提升成果质量。归纳了数字化调绘流程标准、数字化调绘技术要求标准与调绘成果标准,并在宜涪铁路得到了良好的工程验证。总结发现,室内外协同作业模式能适当减少室外工作量,提升工程地质调绘的效率与质量;室内虚拟地质调绘能合理利用丰富的数据,扩展地质调绘的宏观视角与成果的连续性;独立配置的地质调绘模板,保证了室内外地质调绘体验的一致性与数据的传承性,降低了软件系统的维护难度。 相似文献
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核工业北京地质研究院于1990年10至12月采用海燕号轻型飞机与AφA-41型航摄仪匹配,在江西省东乡—礼陂、茅排和邹家山的三个测区完成了2千多km~2的彩红外航空摄影任务。航摄比例尺为1:20000;1:12000和1:8000,为该区铀(金)矿地质研究和矿区测图提供了大量航片和有关资料。近一年来,本航片通过解泽、野外验证,邹家山测区作了1:2000的航测控制测量,外业调绘和内业成图,取得了良好效果,深受用户欢迎。核工业华东地质勘探局270研究所和 相似文献
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在大比例尺地形图测量工作中，相对于传统的方法，无人机倾斜摄影测量技术具有工作周期短、成本低的优点。其工作过程为：首先，通过野外航空摄影建立实景三维模型图；然后，用软件进行立体测图，对不能准确判读的部位进行野外调绘，对影像不清的部位用RTK方法补测数据；最后，对立体测图、调绘和补测数据进行处理，形成地形图。 相似文献
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基于HJ-1B卫星数据的积雪面积制图算法研究 总被引：2，自引：0，他引：2
积雪是影响气候变化的重要因子, 采用更高时空分辨率的环境减灾卫星遥感数据进行积雪制图算法的研究, 对推进我国自主遥感卫星在积雪监测领域的应用具有重要意义. 采用环境减灾HJ-1B卫星数据, 以青海省果洛藏族自治州达日县为研究区, 应用归一化差值积雪指数(NDSI)法建立了基于HJ-1B卫星数据的积雪面积制图算法, 并比较MODIS与HJ-1B积雪图精度. 结果表明: 研究区HJ-1B积雪制图合理的NDSI阈值为0.37, 总分类精度达到97.97%; 与"真值"影像比较, HJ-1B积雪图Khat系数为0.911, 高于MODIS的0.817. 说明该研究建立的基于HJ-1B积雪制图算法精度可靠, 适合对研究区积雪进行实时动态监测. HJ-1B更高的空间分辨率对提高研究区积雪覆盖面积监测精度具有重要的使用价值, 但是地形因素是影响HJ-1B数据积雪分类精度的一个重要原因, 随着坡度的增加, 分类误差也随之增大, 尤其是多测误差增加比较显著. 相似文献
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Pre-conditioning factors and susceptibility assessments of Wenchuan earthquake landslide at the Zhouqu segment of Bailongjiang basin, China 总被引：1，自引：0，他引：1
Shibiao Bai Qiang Xu Jian Wang Pinggen Zhou 《Journal of the Geological Society of India》2013,82(5):575-582
In this study, we present a landslide susceptibility assessment carried out after the devastating 2008 Wenchuan earthquake. For the Zhouqu segment in the Bailongjiang basin in north-western China landslide susceptibility was computed by a logistic regression method. This region has been experiencing landslides for a long time, and numerous additional slope failures were triggered by the 2008 Wenchuan earthquake. The data used for this study consists of slope failures attributed to the 2008 earthquake, the 878 post Wenchuan earthquake landslides and collapses inventory build up by combination the field investigation, monoscopic manual interpretation, image classification and texture analysis using SPOT 5 and ALOS remote-sensing image data. All data derived from remote sensing images are validated during field investigations. The landslide pre-disposing factor database was constructed. A digital elevation model (DEM) with a 30 × 30 m resolution, orthophotos, geological and land-use maps and information on peak ground acceleration data from the 2008 earthquake is used. The statistical analysis of the relation between Wencuan earthquake-triggered landslides and pre-disposing factors show the great influence of lithological and topographical conditions for earthquake-triggered slope failures. The quality of susceptibility mapping was validated by splitting the study area into a training and validation set. The prediction capability analysis showed that the landslide susceptibility map could be used for land planning as well as emergency planning by local authorities in this region. 相似文献
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Urban landscape extraction and analysis based on optical and microwave ALOS satellite data 总被引：2，自引：2，他引：0
Accurate mapping of urban land cover from satellite data provides essential input to urban landscape analysis, modelling and urban ecosystem studies. Additionally, analysis of urban landscape metrics will provide a positive step towards comprehensive understanding of the features of urban landscape structure and further planning. In the present study, multi-spectral Advanced Land Observing Satellite (ALOS)/Advanced Visible and Near Infrared Radiometer type 2 (AVNIR-2) images and ALOS/Phased Array type L-band Synthetic Aperture Radar (PALSAR) dual-polarized (FBD) microwave images were used to extract urban land cover information by applying the decision tree method, and additional Advanced Space borne Thermal Emission and Reflection Radiometer Global Digital Elevation Model (ASTER/GDEM) was used to reduce the effects of mountains in Synthetic Aperture Radar (SAR) images due to high backscattering from urban construction land. A set of landscape metrics, such as landscape diversity, edge density and landscape shape indices with supplementary ecological meanings, were chosen to quantitatively analysis urban landscape patterns in arid environments. The overall accuracy assessment result was 91.50%, and the experimental results demonstrate that synergetic use of optical and SAR ALOS data has the potential and advantages for Arid Urban Region mapping, while the decision tree method showed intuitive simplicity and computational efficiency. The quantitative analysis results of landscape metrics showed that distribution of landscape types in Urumqi city were inhomogeneous, the urban landscape dominated by a few classes. Urbanization in this region has resulted in dramatic increases in patch density (PD), edge density (ED) and landscape shape complexity. 相似文献
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Fazel Amiri Vahid Rahdari Saeideh maleki najafabadi Biswajeet Pradhan Tayebeh Tabatabaei 《Environmental Earth Sciences》2014,72(3):801-809
Chah Nimeh reservoirs have served as a water storage facility, especially during droughts over the last three decades. It is also an important wintering site for migratory birds. In this study, thematic mapper time-series data were derived from Landsat images for prolonged droughts that occurred in two satellite images (2002 and 2011). The data derived from these images were used for the detection of changes in land cover and water storage in the reservoirs. First, a vegetation cover map was produced using soil-adjusted vegetation index and field sampling. Subsequently, land use/cover maps were generated using supervised and hybrid image classification method. Using the spatial change detector (SCD v1.0) software extension, the layers were combined and the change map was generated. The overall accuracy of the produced thematic images was assessed in regards to quantity and allocation disagreements. A total of five classes were defined in this investigation: deep water, shallow water, vegetation, salt land and bare land. The results showed that during the period of study, water volume reduced and vegetation cover increased, especially around the reservoirs that are important as shelter for wintering migratory birds. Comparison of land use/cover maps showed the increase in total available surface of shallow water, which indicated an increase in the habitats for surface feeding and diving birds. 相似文献
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中华人民共和国1∶100万数字地质图数据库是根据统一标准和要求编制的专题数字地质图,以中华人民共和国1∶50万数字地质图数据库为数据源,在综合研究的基础上,充分吸收近年来地质调查1∶25万、1∶20万、1∶5万等区调工作新成果、新资料,应用地质编图新技术、新理论和新方法编制而成。以年代地层单位为主、辅以岩石地层的表示方法,侵入岩按“岩性加年代”表示方法,进一步提高了基础地质的研究程度。地质图数据库内容丰富,信息量大,数据量约为1.2 GB,标示了岩石地层单位5347个图例,侵入体“岩性加时代”单位1780个图例,跨省区重要断裂93条,各省（市、自治区）内重要断层558条,同位素年龄数据1545个（组）,有代表性的钻孔382个。所有地质体的面元及线元、同位素年龄和钻孔都建立了相应的属性,相邻图幅之间进行了接图处理,编写了编图说明书和元数据。数据库采用统一的线型库、符号库、色标库等,成图过程全部采用MapGIS6.5平台计算机辅助成图,成图精度高,质量好,符合设计要求,全国64幅图采用分4个片区的工作方法,最后统一编制而成。该数字地质图是目前中国资料最全、内容最新的1∶100万地质图,是中国第一份应用GIS技术的1∶100万数字地质图的最新成果,充分反映了中国地质构造特点和当前地质研究的新水平。 相似文献
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以深圳市东部滨海地区为试验区,对2004年11月21日ASTER遥感数据进行辐射和几何精校正处理,实地建立分类样地;根据多边形样地矢量数据计算分析12类地物在ASTER各波段光谱反射图和分类叠合图,同时进行植被指数和短波红外5个波段主成分分析;结合GIS并利用ASTER光谱波段、第一主成分、植被指数、立体像对生成的地形因子建立土地利用分类决策树表;再根据决策树表对ASTER影像进行土地利用分类。经验证,分类结果总体精度达到85.1%。应用效果表明,利用ASTER数据进行土地现状资源调查具有很好的性价比,能够满足土地利用现状调查的准确度和精度。 相似文献
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T. G. Fritch C. L. McKnight J. C. Yelderman Jr. S. I. Dworkin J. G. Arnold 《Environmental Geology》2000,39(9):1063-1069
The Paluxy aquifer in north-central Texas is composed primarily of Lower Cretaceous clastics. This aquifer provides water
for both domestic and agricultural purposes in the region. The study area for this investigation incorporates the outcrop
and recharge areas, as well as the confined and unconfined portions of the aquifer. The purpose of this investigation is to
develop a predictive modeling approach for evaluating the susceptibility of groundwater in the Paluxy aquifer to contamination,
and then compare this susceptibility evaluation to water-chemistry data collected from wells completed within the aquifer.
Using such an approach allows one to investigate the potential for groundwater contamination on a regional, rather than site-specific
scale. Based on data from variables such as land use/land cover, soil permeability, depth to water, aquifer hydraulic conductivity
and topography, subjective numerical weightings have been assigned according to each variables' relative importance in groundwater
pollution susceptibility. The weights for each variable comprise a Geographic Information System (GIS) map layer. These map
layers are combined to formulate the final pollution susceptibility map. Using this method of investigation, the pollution
susceptibility map classifies 32% of the study area as having low pollution susceptibility, 41% as having moderate pollution
susceptibility, 25% as having high pollution susceptibility, and 2% as having very high pollution susceptibility. When comparing
these modeling results with water-chemistry data from wells within the Paluxy aquifer, the four wells with the highest concentration
of nitrate contamination are all found within regions of very high pollution potential. This confirms the accuracy and usefulness
of the predictive modeling approach for assessing aquifer pollution susceptibility.
Received: 1 June 1999 · Accepted: 30 August 1999 相似文献