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1.
多源遥感数据综合应用是遥感发展的必然趋势,统一的遥感数据空间尺度分级模型是多源数据集成与综合应用的基础。虽然已有多种空间尺度分级模型,但很多主流模型并非出于分尺度综合应用目的,缺乏客观的比较和评价。国家基本比例尺系统作为经过论证、中国应用面最广泛、接受度最高的一种尺度分级系统,是以应用为导向的遥感数据空间尺度分级模型的最优参照系。从不同视觉精度下国家基本比例尺对图像空间分辨率的需求出发,比较各空间尺度分级模型的层级分辨率与需求分辨率的匹配情况,包括OGC Well Known Scale Set的Global CRS84Pixel和Google Maps Compatible,以及NASA World Wind、Google Map、百度地图、天地图等软件平台采用的层级格网系统,以及"五层十五级"遥感数据组织模型,通过对数据信息冗余度的分析,对各个模型进行了评价。结果表明,在高视觉精度应用需求下,"五层十五级"模型与基本比例尺精度要求具有较明显的匹配优势,其次为OGC Google Maps Compatible模型和天地图模型,其余模型平均数据冗余倍数在2倍左右;在低视觉精度应用需求下,"五层十五级"模型平均数据冗余度仍为最低,其次为Google Map模型,其余模型平均数据冗余倍数都在2倍以上。 相似文献
2.
运用高分辨率卫星遥感影像立体像对,利用少量的外业控制点,进行l：10000比例尺地形图立体测图精度试验,获取分辨率更高的彩色影像。 相似文献
3.
CBERS-02B多光谱数据在城市不透水面
估算中的可用性研究 总被引：2，自引：0，他引：2
以厦门岛为研究区,以CBERS-02B的CCD影像为数据源,采用基于可变端元的线性光谱混合模型估算了城市不
透水面组分含量,并探讨了该方法的实现过程与优势。通过端元评估确定了研究区的４个典型端元,即高反射不透水
面、低反射不透水面、高反射土壤和植被。在此基础上,以高、低反射不透水面端元的组分含量对城市不透水面含量
进行估算。精度评价结果显示：基于可变端元的方法要优于一般带全约束法;而在混合像元分解过程中加入全色波段
（band5）有助于提高模型估算精度,使得在像元尺度的精度与采用Landsat的已有报道相近,而在土地利用单元尺度实
现了对城市不透水面的无偏估计。研究实例也表明,尽管目前CBERS-02B数据在辐射定标和地理定位等方面还有待改
进,通过采用适当的处理过程和技术手段,依然能利用该数据对城市不透水面进行有效估算。 相似文献
4.
Feilin Lai 《地理信息系统科学与遥感》2020,57(6):830-844
ABSTRACT Information on urban settlements is crucial for sustainability planning and management. While remote sensing has been used to derive such information, its applicability can be compromised due to the complexity in the urban environment. In this study, we developed a remote sensing method to map land cover types in a large Latin-American city, which is well known for its mushrooming unplanned and informal settlements. After carefully considering the landscape complexity there, we designed a data fusion method combining multispectral imagery and non-spectral data for urban and land mapping. Specifically, we acquired a cloud-free Landsat-8 image and two non-spectral datasets, i.e., digital elevation models and road networks. Then, we implemented a set of experiments with different inputs to evaluate their merits in thematic mapping through a supervised protocol. We found that the map generated with the multispectral data alone had an overall accuracy of 73.3% but combining multispectral imagery and non-spectral data yielded a land cover map with 90.7% overall accuracy. Interestingly, the thermal infrared information helped substantially improve both the overall and categorical accuracies, particularly for the two urban classes. The two types of non-spectral data were critical in resolving several spectrally confused categories, thus considerably increasing the mapping accuracy. However, the panchromatic band with higher spatial resolution and its derived textural measurement only generated a marginal accuracy improvement. The novelties of our work are with the successful separation between the two major types of urban settlements in a complex environment using a carefully designed data fusion approach and the insight into the relative merits of the thermal infrared information and non-spectral data in helping resolve the issue of class ambiguity. These findings should be valuable in deriving accurate urban settlement information which can further advance the research on socio-ecological dynamics and urban sustainability. 相似文献
5.
Invasive exotic plants (IEP) pose a significant threat to many ecosystems. To effectively manage IEP, it is important to efficiently detect their presences and determine their distribution patterns. Remote sensing has been a useful tool to map IEP but its application is limited in urban forests, which are often the sources and sinks for IEP. In this study, we examined the feasibility and tradeoffs of species level IEP mapping using multiple remote sensing techniques in a highly complex urban forest setting. Bush honeysuckle (Lonicera maackii), a pervasive IEP in eastern North America, was used as our modeling species. Both medium spatial resolution (MSR) and high spatial resolution (HSR) imagery were employed in bush honeysuckle mapping. The importance of spatial scale was also examined using an up-scaling simulation from the HSR object based classification. Analysis using both MSR and HSR imagery provided viable results for IEP distribution mapping in urban forests. Overall mapping accuracy ranged from 89.8% to 94.9% for HSR techniques and from 74.6% to 79.7% for MSR techniques. As anticipated, classification accuracy reduces as pixel size increases. HSR based techniques produced the most desirable results, therefore is preferred for precise management of IEP in heterogeneous environment. However, the use of MSR techniques should not be ruled out given their wide availability and moderate accuracy. 相似文献
6.
Exploiting spectral and spatial information in hyperspectral urban data with high resolution 总被引：2，自引：0，他引：2
Dell'Acqua F. Gamba P. Ferrari A. Palmason J.A. Benediktsson J.A. Arnason K. 《Geoscience and Remote Sensing Letters, IEEE》2004,1(4):322-326
Very high resolution hyperspectral data should be very useful to provide detailed maps of urban land cover. In order to provide such maps, both accurate and precise classification tools need, however, to be developed. In this letter, new methods for classification of hyperspectral remote sensing data are investigated, with the primary focus on multiple classifications and spatial analysis to improve mapping accuracy in urban areas. In particular, we compare spatial reclassification and mathematical morphology approaches. We show results for classification of DAIS data over the town of Pavia, in northern Italy. Classification maps of two test areas are given, and the overall and individual class accuracies are analyzed with respect to the parameters of the proposed classification procedures. 相似文献
7.
P. Srinivas V. Raghu Venkataraman I. Jayalakshmi 《Journal of the Indian Society of Remote Sensing》2012,40(3):497-506
Large scale aerial photographs were acquired for one entire district of Andhra Pradesh in the southern India encompassing approx. 10,000 sq.kms. The voluminous data was processed using digital photogrammetry techniques to generate seamless digital orthoimages as a base map for cadastral mapping applications. Historically the cadastral mapping was carried out with traditional surveying methods such as ETS, theodolites not at regular intervals. With the advent of modern surveying & remote sensing techniques, generation of Digital Cadastral Database for Land Information System (LIS) is possible. The trends of cadastral mapping started with individual plan of survey of parcels with local datum and arbitrary map projections. This study essentially required an accurate and standard spatial reference for seamless cadastral mapping over the entire Area of Interest (AOI) in single datum and projection. Towards this a spatial reference in World Geodetic System (WGS 84) datum with Universal Transverse Mercator (UTM) projection was established. The terrain in the study area is moderately undulating and the relief due to manmade features was not so significant. The aerial orthobase was found suitable for delineating and measuring the individual parcels information. A good GCP configuration, triangulation accuracy and reliable and consistent Digital Elevation Model (DEM) was ensured the generation of Digital aerial orthobases with an accuracy of better than 25cm over a distance of 1000m. The orthobase was used for identification, delineation of the cadastre parcels and most importantly to validate the aerial orthobase with the field measurements. 相似文献
8.
Markov-random-field-based super-resolution mapping for identification of urban trees in VHR images 总被引：1，自引：0，他引：1
Juan P. Ardila Valentyn A. Tolpekin Wietske Bijker Alfred Stein 《ISPRS Journal of Photogrammetry and Remote Sensing》2011,66(6):762-775
Identification of tree crowns from remote sensing requires detailed spectral information and submeter spatial resolution imagery. Traditional pixel-based classification techniques do not fully exploit the spatial and spectral characteristics of remote sensing datasets. We propose a contextual and probabilistic method for detection of tree crowns in urban areas using a Markov random field based super resolution mapping (SRM) approach in very high resolution images. Our method defines an objective energy function in terms of the conditional probabilities of panchromatic and multispectral images and it locally optimizes the labeling of tree crown pixels. Energy and model parameter values are estimated from multiple implementations of SRM in tuning areas and the method is applied in QuickBird images to produce a 0.6 m tree crown map in a city of The Netherlands. The SRM output shows an identification rate of 66% and commission and omission errors in small trees and shrub areas. The method outperforms tree crown identification results obtained with maximum likelihood, support vector machines and SRM at nominal resolution (2.4 m) approaches. 相似文献
9.
随着遥感技术的发展,遥感数据获取手段有了长足的进步。测绘部门在生产中也展开了基于高分辨率影像提取地表覆盖等信息。本论文以易康软件作为卫星遥感影像地物提取的平台,研究如何利用高分辨率遥感影像生成地表覆盖分类图,以达到测绘部门在生产中的需求。 相似文献
10.
African highland agro-ecosystems are dominated by small-scale agricultural fields that often contain a mix of annual and perennial crops. This makes such systems difficult to map by remote sensing. We developed an expert Bayesian network model to extract the small-scale coffee fields of Rwanda from very high resolution data. The model was subsequently applied to aerial orthophotos covering more than 99% of Rwanda and on one QuickBird image for the remaining part. The method consists of a stepwise adjustment of pixel probabilities, which incorporates expert knowledge on size of coffee trees and fields, and on their location. The initial naive Bayesian network, which is a spectral-based classification, yielded a coffee map with an overall accuracy of around 50%. This confirms that standard spectral variables alone cannot accurately identify coffee fields from high resolution images. The combination of spectral and ancillary data (DEM and a forest map) allowed mapping of coffee fields and associated uncertainties with an overall accuracy of 87%. Aggregated to district units, the mapped coffee areas demonstrated a high correlation with the coffee areas reported in the detailed national coffee census of 2009 (R2 = 0.92). Unlike the census data our map provides high spatial resolution of coffee area patterns of Rwanda. The proposed method has potential for mapping other perennial small scale cropping systems in the East African Highlands and elsewhere. 相似文献
11.
为更好地发挥遥感技术在城市规划地图制作中的应用，高分辨率遥感影像成为城市地图制作中最重要的数据源。面对地物信息复杂、建筑物众多的城市地区，如何快速提取高分辨率遥感影像地图制作过程中相邻两景影像之间的镶嵌线具有重要意义。本文以国产卫星中分辨率最高、幅宽最小的GF-2影像为数据源，融合建筑物轮廓数据，研究了基于最短路径的A*搜索算法，实现了遥感影像地图制作的镶嵌线自动提取技术。结果表明，该方法能够自动生成避让建筑物的镶嵌线，速度快、镶嵌质量高，可广泛应用于城市地区高分辨率遥感影像地图制作。 相似文献
12.
总结了网格化城市管理新模式由数字城管向智慧城管发展、城市管理范围由建成区向城乡结合部延伸所需解决的问题及对卫星技术应用的迫切需求,结合国家在卫星遥感和卫星导航方面的技术进展,探讨了网格化城市管理卫星技术综合应用服务平台的总体架构设计和主要子系统划分,并对人员和车辆精细化管理、车载视频快速上报城市管理案件、高精度移动测量技术、基于高分辨率遥感影像的城乡结合部基础数据提取技术、基于定位实景融合技术的城管业务动态监管、实景影像动态数据更新技术等关键技术进行了具体阐述。本文的部分研究成果已经在宁波市智慧城管和杭州市实景影像系统建设中进行了示范应用,取得了良好效果。 相似文献
13.
Background
Urban forests reduce greenhouse gas emissions by storing and sequestering considerable amounts of carbon. However, few studies have considered the local scale of urban forests to effectively evaluate their potential long-term carbon offset. The lack of precise, consistent and up-to-date forest details is challenging for long-term prognoses. Therefore, this review aims to identify uncertainties in urban forest carbon offset assessment and discuss the extent to which such uncertainties can be reduced by recent progress in high resolution remote sensing. We do this by performing an extensive literature review and a case study combining remote sensing and life cycle assessment of urban forest carbon offset in Berlin, Germany.Main text
Recent progress in high resolution remote sensing and methods is adequate for delivering more precise details on the urban tree canopy, individual tree metrics, species, and age structures compared to conventional land use/cover class approaches. These area-wide consistent details can update life cycle inventories for more precise future prognoses. Additional improvements in classification accuracy can be achieved by a higher number of features derived from remote sensing data of increasing resolution, but first studies on this subject indicated that a smart selection of features already provides sufficient data that avoids redundancies and enables more efficient data processing. Our case study from Berlin could use remotely sensed individual tree species as consistent inventory of a life cycle assessment. However, a lack of growth, mortality and planting data forced us to make assumptions, therefore creating uncertainty in the long-term prognoses. Regarding temporal changes and reliable long-term estimates, more attention is required to detect changes of gradual growth, pruning and abrupt changes in tree planting and mortality. As such, precise long-term urban ecological monitoring using high resolution remote sensing should be intensified, especially due to increasing climate change effects. This is important for calibrating and validating recent prognoses of urban forest carbon offset, which have so far scarcely addressed longer timeframes. Additionally, higher resolution remote sensing of urban forest carbon estimates can improve upscaling approaches, which should be extended to reach a more precise global estimate for the first time.Conclusions
Urban forest carbon offset can be made more relevant by making more standardized assessments available for science and professional practitioners, and the increasing availability of high resolution remote sensing data and the progress in data processing allows for precisely that.14.
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Landsat8和MODIS融合构建高时空分辨率数据识别秋粮作物 总被引：2，自引：0，他引：2
本文利用Wu等人提出的遥感数据时空融合方法 STDFA(Spatial Temporal Data Fusion Approach)以Landsat 8和MODIS为数据源构建高时间、空间分辨率的遥感影像数据。以此为基础,构建15种30 m分辨率分类数据集,然后利用支持向量机SVM(Support Vector Machine)进行秋粮作物识别,验证不同维度分类数据集进行秋粮作物识别的适用性。实验结果显示,不同分类数据集的秋粮作物分类结果均达到了较高的识别精度。综合各项精度指标分析,Red+Phenology数据组合对秋粮识别效果最好,水稻识别的制图精度和用户精度分别达到91.76%和82.49%,玉米识别的制图精度和用户精度分别达到85.80%和74.97%,水稻和玉米识别的总体精度达到86.90%。 相似文献
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本文综述全球定位系统(GPS)在航空遥感自动精确定位中的应用现状和发展前景,着重叙述了GPS用于航空遥感定位的可能性和用机载GPS接收机按相位差分法进行航空遥感定位(空中三角测量)的一个典型试验结果。理论研究和实验表明,由于动态GPS定位技术具有很高的精确性和可靠性,它可用于从1:500到1:10万比例尺的各种地形图和专题图制作,以及诸如坐标地籍等高精度点位测定。文中还展望了GPS技术在航空、航天遥感中进一步利用的可能性。 相似文献
19.
Quantifying impervious surfaces in urban and suburban areas is a key step toward a sustainable urban planning and management strategy. With the availability of fine-scale remote sensing imagery, automated mapping of impervious surfaces has attracted growing attention. However, the vast majority of existing studies have selected pixel-based and object-based methods for impervious surface mapping, with few adopting sub-pixel analysis of high spatial resolution imagery. This research makes use of a vegetation-bright impervious-dark impervious linear spectral mixture model to characterize urban and suburban surface components. A WorldView-3 image acquired on May 9th, 2015 is analyzed for its potential in automated unmixing of meaningful surface materials for two urban subsets and one suburban subset in Toronto, ON, Canada. Given the wide distribution of shadows in urban areas, the linear spectral unmixing is implemented in non-shadowed and shadowed areas separately for the two urban subsets. The results indicate that the accuracy of impervious surface mapping in suburban areas reaches up to 86.99%, much higher than the accuracies in urban areas (80.03% and 79.67%). Despite its merits in mapping accuracy and automation, the application of our proposed vegetation-bright impervious-dark impervious model to map impervious surfaces is limited due to the absence of soil component. To further extend the operational transferability of our proposed method, especially for the areas where plenty of bare soils exist during urbanization or reclamation, it is still of great necessity to mask out bare soils by automated classification prior to the implementation of linear spectral unmixing. 相似文献