A Novel Approach to Estimate Diffuse Attenuation Coefficients for QuickBird Satellite Images: A Case Study at Kish Island, the Persian Gulf

Diffuse attenuation coefficient (k _d ) is a critical parameter for benthic habitat mapping using remotely sensed data. This research attempted to develop a new approach to estimate k _d in blue and green bands of QuickBird satellite image based on the integration of Lyzenga’s method and updated NASA-k _d ⁴⁹⁰ algorithm. To do this, the Lyzenga’s method was utilized to determine the ratio of k _d in different bands of QuickBird satellite image. Additionally, NASA-k _d ⁴⁹⁰ algorithm was applied to determine k _d ⁴⁹⁰ by using remotely sensed reflectance values of blue (R _rs ^Blue ) and green (R _rs ^Green ) bands in each pixel of QuickBird satellite image. Since the aforementioned algorithm has been developed for other types of sensors, an approach using weighted mean value of parameters for SeaWiFS, MERIS, VIIRS, and OCTS sensors were employed to estimate parameter values for QuickBird image. After determining the k _d ⁴⁹⁰ values as k _d for blue band, the k _d values for green and red bands were subsequently obtained by using Lyzenga’s method. Then, Mumby and Edwards’ method was employed as evidence to evaluate the accuracy of the results achieved from newly developed approach. Eventually, the maximum likelihood classifier was implemented during pre and post correction steps to examine the capability of the proposed approach. The final results proved to be consistent in the areas deeper than 2 m between estimated k _d values using the proposed approach and the results obtained from Mumby and Edwards’ method. On the other hand, the values estimated for extremely shallow areas seem to be overestimated. Furthermore, results demonstrated an increment of ~16 % in the overall accuracy of the classification.     

GML for Representing Data from Spatio-Historical Databases: A Case Study

Many applications, in areas such as land use, traffic management and location aware services, involve the storage, analysis and sharing of spatio‐temporal data. The need to represent such data in a way that eases sharing across applications, has led to the development of the Geography Markup Language (GML), which provides a rich collection of constructs for representing spatial and associated aspatial data as XML documents. However, although there are a growing number of applications and tools that make use of GML, there are surprisingly few experience reports on the representation of data from existing applications or models using GML constructs. This paper provides one such report, describing the use of GML as an exchange format for the Tripod spatio‐historical database. This in turn involves identifying mappings between Tripod and GML constructs, and the development of a generic architecture for carrying out such mappings. The experience demonstrates that even though GML provides rich modelling facilities, the development of mappings from pre‐existing models can be challenging, as related constructs often provide semantically distinct capabilities.     

A Doubly Weighted Approach to Urban Data Disaggregation in GIS: A Case Study of Wuhan, China

Urban models are evolving to require more and more detailed data that in many cases have to be spatially disaggregated from larger zones. This paper deals with the disaggregation of statistical data in an urban context in which land use data are available at a less detailed level. With the availability of land use data, the traditional approach of areal weighting is improved with an areal and land use weighted approach. This weighted approach is further elaborated to include homogeneous weight zones (HWZ) so as to reflect general geographical variations among the same land use type. A case study in Wuhan, China has demonstrated the effectiveness of the doubly weighted approach within the specified context.     

ASTER数据在北方铝土矿预普查中的应用——以豫西渑池地区为例

ASTER数据的光谱和空间分辨率均具有一定优势,适合于中等比例尺的矿产预普查。为了探讨ASTER数据应用于铝土矿预普查的效果,通过对ASTER图像彩色合成、地质解译及异常信息提取,对豫西渑池地区的铝土矿进行了预普查试验。结果表明,在北方基岩裸露地区,应用ASTER数据圈定"赋矿影像单元"和提取铝土矿遥感找矿信息能获得较好的效果。     

遥感在东太湖水环境研究中的应用

本文主要介绍应用多层次、多时相遥感图像研究东太湖水环境的演变的成果。作者将多时相 遥感图像与实时水位资料结合进行了湖盆的三维分析,并对径流流态、水质、水生植物以及围湖。 港、闸等人类工程进行了动态解译。认为东太湖水环境的恶化,是太湖地区洪水情势日益严重的 主要原因之一。 东太湖的退化还与水生植物迅速繁殖有关,并存在着富营养化的危险。若不及时治理,预计 公元2000-2010年间,因东茭咀滩地的扩展,东太湖将与太湖主体隔离,并趋于湮废,目前太湖 的主要排洪工程──太浦河将失效。根据此情势,本文提出了工程措施和生态工程治理相结合的 综合治理设想。     

An Agent-Based Approach for Regional Forest Fire Detection Using MODIS Data: A Preliminary Study in Iran

Detecting fires, which are at their early stages is the first component of effective fire fighting. To date, several algorithms have been proposed to detect fire spots using remote sensing data. Nevertheless, in order to be able to accurately detect small and cool fires, which are very important at the regional scale, most of these algorithms need to be adjusted and improved. In this paper, an agent-based algorithm is presented for regional forest fire detection using bi-temporal MODIS data. The algorithm is designed to be so self-adaptive and consistent that it could be applied to the different pairs of consecutive images taken by the same satellite platform and at the same daytime. The results clearly show that compared with the MODIS contextual algorithm (version 4), the proposed method is more sensitive to small and cool forest fires in Iran.     

Multi-sensor Space-Borne Earth Observation Data for Characterizing Fluvial-Geomorphic Provinces: A Case Study from Kosi River,India

The dynamism of geomorphic provinces in fluvial systems present considerable ambiguities in mapping by remote sensing. This necessitates use of multiple satellite data to characterize such depositional provinces. We use, an integrated dataset to characterize the geomorphic provinces (e.g. active flood plain, older food plain, fan etc.) of the Kosi River (Bihar), India. This is done using contrast in spectral signatures derived from multispectral bands (of IRS-P6 LISS III), radiant temperature (from ETM+) and radar-roughness (from radar brightness image RISAT-1). ASTER DEM has been used in deriving topographic profiles. The optical imagery, enables regional characterization through direct tonal changes (e.g. active flood plain is brighter than older flood plain). The radiant temperatures show variations across provinces. Geomorphic transitions are represented by topographic breaks. Radar backscatter imagery, show differences in radar-return from different sub-provinces. Observations made using specific sensor characterize each provinces and is supplementary/complimentary to the parameter(s) from other sensors.     

基于POI数据的广场功能研究——以兰州市城关区为例

基于ArcGIS中的网络分析法,选取兰州市城关区东方红广场、五泉下广场和万达广场构建沿不同等级交通线的1 min、1.5 min、3 min 3个缓冲区圈层,同时统计不同缓冲区内居住设施、公共管理与公共服务设施和商业设施三大类兴趣点(point of interest,POI)数据的数量与占比.结果显示,东方红广场的交...     

地理国情在自然保护区生态环境监测中的应用研究——以兴凯湖国家级自然保护区为例

地理国情监测是为了获取自然与人类社会活动引起的地表变化信息,为政府、行业和公众提供地理国情信息服务,自然保护区生态环境是地理国情监测的重点之一。本文以兴凯湖国家级自然保护区为例,基于多期地理国情普查成果,确定监测内容与指标,并有针对性地对监测结果进行对比分析,以反映该保护区的现状和变化情况。     

省级国土资源数据应用模式及布局策略研究——以陕西省多级国土资源数据为例

国土资源数据高效存储技术及策略是国土资源信息化的基础,本文基于对省内多级行政单元国土资源数据特征及管理需求分析,提出了省内多级行政单元国土资源数据应用模式及数据布局策略,并以陕西省实际数据为例,形成了对我国国土资源数据管理部门具有重要参考价值的结论。     

ETM数据在金矿化蚀变信息提取中的应用研究——以张家口下双台地区为例

金矿遥感探测之关键在于成矿构造及铁氧化物、含羟基蚀变矿物信息的提取。以张家口下双台地区为研究区,利用ENVI 4.0图像处理软件,通过"多元数据分析+比值+主成分变换+密度分割+分类"等方法,从Landsat-7 ETM数据中提取矿化蚀变信息并抑制植被波谱干扰,方法快速、准确、有效。结果表明,利用该方法获得的矿化蚀变信息与已知矿点有很大的一致性,该方法是可行的。     

不动产存量数据整合实践

不动产存量数据整合是将现有存放分散、格式不一、介质不同的不动产历史登记数据进行统一梳理,具体包括冗余数据清理、业务数据整合、权属数据与空间数据关联、房地数据绑定等,该工作是实现不动产统一登记的基础。本文以海淀区不动产数据为例,分析存量数据特点,提出不动产存量数据整合的技术路线与方法。目前,该技术在北京市海淀区不动产数据整合的实际工作中得到了充分应用,取得了良好效果。     

基于Web GIS的电子商务数据挖掘研究

文中对Ansari 等提出的基本的电子商务应用框架做了进一步的细化和补充,详细分析了数据收集和数据挖掘问题,包括数据来源、数据类型、数据收集器工作、数据转化、数据库建立和搜寻规则构建等.在此基础上,探讨了数据挖掘技术在基于Web GIS的电子商务中的具体应用.最后讨论了将数据挖掘技术应用于电子商务数据挖掘的最终目的和目前尚面临的一些困难.     

基于Web GIS的电子商务数据挖掘研究

文中对Ansari等提出的基本的电子商务应用框架做了进一步的细化和补充，详细分析了数据收集和数据挖掘问题，包括数据来源、数据类型、数据收集器工作、数据转化、数据库建立和搜寻规则构建等。在此基础上，探讨了数据挖掘技术在基于Web GIS的电子商务中的具体应用。最后讨论了将数据挖掘技术应用于电子商务数据挖掘的最终目的和目前尚面临的一些困难。     

基于带模型的叶绿素a浓度反演精度评估

为了评估遥感反演叶绿素a浓度的精度,以2004年8月19日太湖38个水质样本数据和同步Hyperion卫星遥感影像数据为基础,借鉴四波段半分析算法,结合空间数据不确定性原理,构建了基于四波段半分析算法的“带模型”.通过研究与探讨可知,当叶绿素a浓度为10～20 μg/L和50～100 μg/L时,叶绿素a浓度的反演误差...     

The Potential of Virtual Reality Technology for Analysis of Remotely Sensed Data: A Lidar Case Study

Abstract

Although the GIS community has been quick to exploit the advantages of virtual reality (VR) for display and analysis of spatial data, VR does not appear to have been exploited widely for remote sensing data analysis. A case study of high resolution lidar data acquired over a deciduous forest near Morgantown, WV was used to investigate the potential and limitations of current VR software for remote sensing analysis. The functionality within a standard remote sensing software package was found to provide a good overview of interpolated, smoothed lidar data, but was less useful for gridded data that had not been interpolated. With gridded data, it was possible to drape orthophotographs or other images over the lidar data, providing a useful method for investigating relationships between lidar and other data. Alternatively, using a commercial VR package, it was possible to view the original lidar point data, and thus visualize the multiple returns from within the canopy of each tree. The point data were preferable for identification of surfaces within the data cloud, especially the ground surface. For a fully integrated remote sensing VR package, functionality will be needed to link point and interpolated coverages, and also to enhance the interactive selection of data for further statistical analysis.     

基于资源一号02C卫星数据的土地执法监察应用研究--以浙江长兴县为例

利用资源一号02 C卫星数据,对长兴县进行半年度土地利用变化动态遥感监测,并尝试在土地执法监察中开展应用研究。在02 C遥感影像数据处理（配准、纠正、融合）基础上,采用计算机自动识别结合目视判读的人机交互式解译方法,从融合影像上提取新增建设用地变化信息并形成监测成果。研究表明：利用02 C星高分辨率2．36 m数据与多光谱10 m数据的融合影像,能够较好地识别新增建设用地变化情况,并能较为准确地提取变化信息。研究结果显示：遥感监测结果能够为土地执法监管提供可靠的数据支撑,作为整改查处工作的依据。02 C星在国土资源土地监管方面具有较好地应用潜力。实证研究有效促进县级土地监管水平迈上新台阶,利用国产02 C卫星和高科技手段对提高土地执管能力具有现实意义和作用。