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1.
浮动车轨迹数据具有覆盖范围广、更新周期短、获取成本低等特点,对于地图的生产和更新具有重要意义,但是由于受到卫星信号被遮挡及多路径效应的影响,其精度普遍较低。本文采用一种基于OSM作为参考数据的方式对浮动车轨迹数据进行校正。首先通过一种分层时空地图匹配的方式将轨迹数据与OSM进行匹配;然后采用引力模型对数据进行校正;最后在武汉市出租车轨迹数据上进行了试验。结果表明,本文提出的数据校正方法可以有效地提高浮动车轨迹数据的精度。  相似文献   
2.
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   
3.
湖南地矿行业多采用MapGIS软件进行地质数据的管理和分析,然而,该软件在数据处理和分析方面略显不足,尤其在处理大数据时更是力不从心,且其中的67版本难以满足2000坐标系统的要求。因此,为了更加有效地使用已有的数据,并充分发挥其价值,本文以麻阳县地质图为例,通过研究MapGIS和ArcGIS软件之间的异同,总结出一套较为完整的MapGIS到ArcGIS格式的数据转换方法,使得转换前后的数据在数量、样式、属性等方面基本保持一致。  相似文献   
4.
China has a vast area of mountains that are of great research interest. Chongqing is a typical mountain city in China. In urban construction, a mountain is not only an important limiting condition for urban development, but also an important condition for shaping the urban form. The area from the Yangtze River to the eastern ridge line of Nan Mountain in Nanan District is strongly representative of mountain cities with a complex landform, fragile ecological environment and a long history and culture. In recent years, the construction and optimization of this area are increasingly closely related to the landscape environment. However, due to the special environments of mountain cities, altitude and landform conditions become the key influencing conditions for further development of the cities. Therefore, this paper takes this region as an example, focuses on remote sensing and field measurement data, combines government data with that from scholarly research, and conducts relevant exploration through GIS, ENVI and some chart processing software. At first, from the perspective of the landscape gradient and urban construction, the characteristics of the urban landscape gradient are sorted out, and the developmental status of each urban area is analyzed. Then, the coupling relationships between the landscape features of each gradient and each urban area are analyzed. Finally, based on the analysis results, three major optimization measures are proposed to maintain ecological harmony in the mountainous area, reconstruct the mountain characteristic culture, and create unique mountain aesthetics, all with the hope of providing some guidance for the future development of the study area and similar mountain cities.  相似文献   
5.
土地景观形态能够反映土地利用空间行为特征。在对鄱阳湖地区1995年、2000年、2015年和2018年4个时间点的土地利用现状进行描述的基础上,通过分形维数、分形稳定性、斑块密度、斑块形状破碎度和景观隔离指数分析区域景观格局变化,并运用分形理论对土地利用空间行为进行分析。研究结果显示在1995年到2018年的20多年间,建设用地一直是分形维数最高的土地类型;但从时间尺度上,建设用地的分形维数呈下降趋势,表明建设用地空间形态在土地利用空间行为的作用下逐渐向有序方向发展。水田、旱地和有林地一直是分形维数最低的土地利用类型,且处于景观分形不稳定状态。斑块密度、斑块形状破碎化指数以及景观分离度指数的计算结果支持了分形维数分析的结论。从实现区域土地合理布局的角度,建议通过科学合理的规划,降低区域建设用地的分形维数,引导建设用地有序发展。对于诸如有林地、灌木林地、高覆盖度草地和水域等自然景观,应增加其分形维数以减少人为干扰,维护其稳定性。同时建议在国土空间规划中引入分形维数,将分形维数作为评价区域土地利用格局合理性的一项指标。  相似文献   
6.
农村居民点作为乡村区域空间人口集聚形态的一种表现,是构成乡村聚落景观的一个重要部分,对其特征的分析研究对于推动城乡一体化建设和美丽乡村建设等政策的理论研究和实践开展和促进农村土地节约集约利用有重要意义。运用Ripley's K函数和ArcGIS 10.2中的核密度法来研究广东省揭阳市农村居民点的空间分布特征,建立河流和道路的缓冲区,从景观生态学的角度进一步分析影响居民点空间格局分布的因素,得出以下结论:(1)揭阳市农村居民点的空间分布格局属于集聚分布。(2)60%以上的农村居民点集中分布在由榕江、龙江和练江三大水系构成的河网体系周边。(3)农村居民点主要集聚在普宁、榕城、揭东、蓝城和空港经济区的县区范围。  相似文献   
7.
Yanchi County is located in the agro-pastoral ecotone and belongs to the ecologically fragile area of Northwest China.It is important to study the evolution of landscape pattern to curb its environmental degradation.In order to intuitively show how the landscape pattern of the study area changes over time,Landsat Thematic Mappers(TM)and Landsat Operational Land Imager(OLI)data of 1991,2000,2010 and 2017 were used.This paper attempts to apply niche theories and methods into landscape ecology,and constructs a niche model of landscape components by using"n-dimentional hypervolume niche theory"and landscape pattern indices.By evaluating the spatial and temporal evolution of niche from the perspective of two-dimensional space to reflect the changes of landscape pattern in the study area over the past 26 years,new theories and methods were introduced for the characterization of landscape pattern.The results indicate that:1)The larger the attribute and dominance value of landscape components,the higher the ecological niche and the stronger the control effect on the overall landscape.2)The ecological niche of each landscape component was significantly different,just as its control effect on the overall landscape.3)The dynamic change of the ecological niche of each landscape component was different,with grassland,unused land and arable land always in a high dominant position,although the ecological niche of construction land and water area was always low.In general,the introduction of niche theory into the landscape ecology provided a new method to study the changes in regional landscape pattern.  相似文献   
8.
柴达木盆地1:50 000尕海镇幅水文地质图数据集   总被引:1,自引:1,他引:0  
尕海镇幅位于柴达木盆地东北缘的巴音河山前平原,是1:50 000国际标准图幅。其水文地质图是根据中国地质调查局组织编制并即将颁布实施的《水文地质图编制规范(1:50 000)》的基本要求,结合区内发展建设的需求,利用2016年1:50 000水文地质调查最新获取的尕海镇幅钻孔抽水试验成果数据(本次施工以及收集已有钻孔资料共48个钻孔),水化学(61个水样)、同位素(12个同位素样)和土壤易溶盐(55个土样)分析成果数据,地下水位统测成果数据(68个统测点),以及已有资料与成果数据编制而成。编图以地下水系统理论和生态水文地质理论为指导,按地下水系统、水文地质结构、含水岩组及富水性、地下水补给-径流-排泄条件、地下水化学特征、地下水水位埋深与流场、地下水与生态植被关系、地下水开发利用等分类加工处理数据形成水文地质图数据集,使大量的信息在图面上以主图结合镶图的形式主次分明、层次清晰地加以展现,以便为当地水资源开发利用和生态环境保护提供直观易用的地下水资料支撑。  相似文献   
9.
对内蒙古陶来托钼多金属勘查区进行地质、地球物理、地球化学综合找矿信息的提取来评价矿区找矿潜力。结果表明,陶来托钼多金属矿是一个以斑岩型钼矿为主的勘查区,发现了斑岩型钼矿床及多处热液脉型铅锌银矿(化)点。成矿岩体为早白垩世花岗斑岩,控矿构造为北东-北北东向断裂。斑岩型钼矿化区与环状激电异常和环状磁异常对应性较好,显示出中低视极化率异常为矿致异常的特征。1∶5万化探异常元素由钼矿化区至铅锌银矿化区表现出Mo、W—Ag、Pb、Zn的侧向分带特征。根据综合找矿信息提取及斑岩型矿床成矿系列建立,指出区内钼矿找矿潜力较大,并预测钼矿区北西侧为热液脉型铅锌银矿的成矿有利地段。  相似文献   
10.
We present a study on human perception of map complexity, with the objective of better understanding design decisions that may lead to undesirable levels of complexity in web maps. We compare three complexity metrics to human ratings of complexity obtained through a user survey. Specifically, we use two algorithmic approaches published by others, which measure feature congestion (FC) and subband entropy (SE), as well as our own approach of counting object types rather than individual objects. We compare these metrics with each other as well as with human complexity ratings for three maps of the same area from map providers Google Maps, Bing Maps, and OpenStreetMap. Each map design is assessed at three different scales (levels of detail). We find that (1) the FC and SE metrics appear to be adequate predictors of what humans consider complex; (2) object-type counts are slightly less successful at predicting human-rated complexity, implying that clutter is more important in perceived complexity than diversity of symbology; and (3) generalization choices do impact human complexity ratings. These findings contribute to our understanding of what makes a map complex, with implications for designing maps that are easy to use.  相似文献   
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