基于遥感的黄河三角洲地区盐碱地分布监测

借助遥感技术可以快速准确提取盐碱地分布信息,本文使用TM遥感影像,利用光谱分析和图像处理相结合的方法,参考地理数据,对黄河三角洲地区盐碱地的分布状况进行了遥感分析。通过最大似然分类及神经网络亚像元分类两种监督分类方法的分类精度比较后发现,后者分类精度得到有效提高,总体分类精度从80.8%上升到85.6%,对于盐碱地地类的分类精度提高到85.45%。最后,在此基础上给出了该地区盐碱地分布图。     

基于遥感反演河套平原区域蒸发蒸腾量研究

采用SEBS模型,结合地面站点观测的温度、湿度、风速、日照时数等气象数据,利用MODIS/TERRA卫星遥感影像,反演河套平原2006年日蒸散发量,对河套平原蒸散发量进行分析研究。并结合彭曼公式计算的理论蒸散发量的年内分布规律进行分析,对河套平原实际蒸散发量进行时间尺度推演,对河套平原区域蒸散发量的时间分布特点进行了分析。     

多尺度遥感影像融合技术及其算法研究进展

随着传感器光谱分辨率和空间分辨率的提高,现代遥感技术提供了金字塔状的可利用遥感数据。与此同时,也给遥感技术应用提出了挑战———如何充分、有效地利用多源、多尺度的遥感影像数据。影像融合技术为充分利用多源、多尺度的遥感影像数据提供了有效的途径。本文对目前多尺度影像融合技术及其算法的发展进行了系统分析,在此基础上,对影像融合技术的发展进行了简要的分析。     

重视遥感技术在防震减灾中的作用

利用遥感技术可以在地震灾害救灾或者评估过程中进行以下工作：第一,利用中低分辨率的遥感影像获取震后灾情的宏观分布情况,以判断地震的影响范围,对活动断层、地震破裂带及次生地质灾害进行调查,分析活动断层的几何特性、构造地貌等;第二,利用高分辨率的遥感影像可以得到震态房屋的详细破坏情况,以满足灾情的详细判断和震灾评估的精度要求,     

航测内业中遥感影像融合方法

科学技术的不断进步促进了现代遥感技术的发展,通过航测获得的遥感数据精度也越来越高,不同时相、不同分辨率、不同传感器获得的遥感数据的融合也显得越来越重要。本文分析多源遥感数据的融合技术,探讨各种技术之间的优点和缺点,以促进业内对遥感影像融合方法的探索,提高遥感影像的利用价值。     

基于ERDAS LPS的无人机遥感影像技术

随着遥感技术的发展,遥感航拍数据成为了部分行业不可或缺的基础资料。在环境恶劣的地区,卫星航拍造成数据难以接收、影像使用率低等问题,而无人机遥感技术却可以解决这些问题。基于此,研究、分析了ERDASLPS的无人机遥感影像快速处理技术,并提出了提高DEM精度的解决办法,为后期对无人机遥感影像技术的研究提供一定参考依据。     

一种格网补偿的遥感影像数据检索方法

随着遥感技术的快速发展,当前遥感影像数据的数据总量急剧增加。面对海量遥感影像数据的应用需求,如何快速、准确的获取全覆盖特定区域的无云遥感影像数据至关重要。因此,笔者提出了一种格网补偿的遥感数据全覆盖检索方法。首先,利用五层十五级格网切分模型对特定区域切分成较小的格网。其次,对海量遥感有云影像数据集进行预处理,采用基于快视图的云检测方法判断快视图局部是否无云,取出无云的部分对每个格网进行像素补偿。最后得出一张全覆盖特定区域的无云遥感图像,并筛选出所需的遥感影像数据。通过实验对比,该方法在海量遥感影像数据情况下,能快速、准确的获取全覆盖特定区域的无云遥感影像数据,具有很好的可行性和实用性。     

遥感影像融合及高保真算法比较分析研究

随着传感器性能的提高,现代遥感技术提供了各种光谱分辨率、空间分辨率的遥感数据,如何充分、有效的利用多源、多尺度遥感影像数据成为遥感应用技术的一个挑战。本文系统阐述了遥感影像融合的理论和方法,详细分析了像素级、特征级、决策级遥感影像融合的方法和优缺点,深入探讨了Gram-Schmidt和SFIM两种高保真的融合方法,给出了融合结果的评价体系,结果表明SFIM融合方法是最优方法。     

土壤盐碱化遥感应用研究进展

对近年来国内外遥感监测土壤盐碱化的研究进展作了介绍,并从土壤盐碱化遥感信息特性和影响因素、各种遥感数据源、数据处理方法和研究热点等方面做了总结。土壤盐碱化的遥感方法和传统方法可获取多源的数据,包括来自多平台遥感的光谱数据、地面实测和实验室分析数据、其它研究手段得到的地理相关数据以及历史资料等。在GIS技术支持下的多源数据集成方法可对土壤盐碱化进行定量探测,在土壤盐碱化遥感应用中取得了较好的效果。     

面向Spark的遥感影像金字塔模型的并行构建方法

随着遥感技术和摄影测绘的发展,遥感影像的分辨率不断提高,数据量日益增长,这对快速、高效地处理海量遥感影像数据提出了更高的要求,如何有效、智能地存储和处理海量遥感数据成为研究的热点。在分析现有金字塔模型的并行构建的基础上,设计一种面向Spark计算框架的影像金字塔模型。模型给出了影像金字塔构建算法及影像数据的分布式存储组织结构,实现了海量遥感影像数据在Spark中的并行处理,为Spark增加了计算处理空间数据格式的能力。实验结果表明,利用该方法能够在Spark云平台上实现快速、高效的解决海量遥感影像金字塔的并行构建,特别是在面对海量遥感影像数据时,无论从金字塔构建性能上还是遥感影像的计算效率上,Spark都更具优势。     

咸蛋快速腌制生产装置的设计与应用

针对目前主流的脉动压技术腌蛋法,设计了咸蛋快速腌制生产装置。该装置主要由压力腌制罐、压力源、压力与温度控制系统组成,具有腌制罐耐压要求低、受环境影响小、腌制周期短、腌制方法简单等特点,不仅适用于批量生产咸蛋的副食店、单位食堂、禽类养殖专业户等小规模使用,还可以在咸蛋生产企业进行大规模应用。     

Super resolution land cover mapping of hyperspectral images using the deep image prior-based approach

ABSTRACT

Due to the instantaneous field-of-view (IFOV) of the sensor and diversity of land cover types, some pixels, usually named mixed pixels, contain more than one land cover type. Soft classification can predict the portion of each land cover type in mixed pixels in the absence of spatial distribution. The spatial distribution information in mixed pixels can be solved by super resolution mapping (SRM). Typically, SRM involves two steps: soft class value estimation, which is similar to the image super resolution of image restoration, and land cover allocation. A new SRM approach utilizes a deep image prior (DIP) strategy combined with a super resolution convolutional neural network (SRCNN) to estimate fine resolution fraction images for each land cover type; then, a simple and efficient classifier is used to allocate subpixel land cover types under the constraint of the generated fine fraction images. The proposed approach can use prior information of input images to update network parameters and no longer require training data. Experiments on three different cases demonstrate that the subpixel classification accuracy of the proposed DIP-based SRM approach is significantly better than the three conventional SRM approaches and a transfer learning-based neural network SRM approach. In addition, the DIP-SRM approach performs very robustly about small-area objects within multiple land cover types and significantly reduces soft classification uncertainty. The results of this paper provide an extension for utilizing SRCNN to address SRM issues in hyperspectral images.     

Beyond the urban-rural dichotomy: Towards a more nuanced analysis of changes in built-up land

Urban land and rural land are typically represented as homogenous and mutually exclusive classes in land change analyses. As a result, differences in urban land use intensity, as well as mosaic landscapes combining urban and rural land uses are not represented. In this study we explore the distribution of urban land and urban land use intensity in Europe and the changes therein. Specifically, we analyze the distribution of built-up land within pixels of 1 km². At that resolution we find that most built-up land is distributed over predominantly non-built-up pixels. Consistently, we find that most urban land use changes between 2000 and 2014 come in small incremental changes, rather than sudden large-scale conversions from rural to urban land. Using urban population densities, we find that urban land use intensity varies strongly across 1 km² pixels in Europe, as illustrated by a coefficient of variation of 85%. We found a similarly high variation between urban population densities for most individual countries and within areas with the same share of built-up land. Population changes have led to different combinations of urban land expansion and urban intensity changes in different study periods (1975–1990, 1990–2000, and 2000–2015) and countries. These findings suggest that land use change models could be improved by more nuanced representations of urban land, including mosaic classes and different urban land use intensities.     

A quantitative investigation of the uncertainty associated with mapping scale in the production of land-cover/land-use data

ABSTRACT

Mapping scale is an essential issue in land use and land cover (LULC) data production, which always involves the minimum mapping unit (MMU) that stipulated in the product specification. Since the application of MMUs will inevitably cause some inappropriate classification problems, a technique is needed to evaluate the impact on the data outputs. In this study, a novel method is proposed to investigate the classification uncertainty brought by MMUs on LULC data. The omission errors are predicted based on an assumption of the skewed frequency distribution of the LULC patch size, and the commission errors are subsequently computed through the conversion possibilities among different land classes, which can be deduced from the generalization rule. A test is conducted on real data to verify the underlying assumption on the patch size distribution, and the accuracy of the prediction of omission errors is evaluated through a simulation experiment. A case study is also presented to demonstrate the efficiency and feasibility of the proposed method. At the end of this article, the advantages and notes of this method are discussed for further study and application.     

城市开敞空间的地表能量响应初探——以国际宜居城市为例

城市开敞空间是城市的重要组成部分,其构成与分布影响城市遥感地表能量的平衡。本研究从城市生态系统层面,通过相对地表能量信息的定量分级方法,探讨宜居城市开敞空间地表能量的综合响应特征、作用与影响关系特征。从开敞空间的属性、体量、结构方面,分析其对城市地表能量空间分布的格局、状态、质量及其时空变化的作用与影响。结果表明：(1) 在城市生态系统层面,城市开敞空间构成的属性、体量和结构是影响城市地表能量变化的基础;(2) 相对于城市的实体空间,城市开敞空间的地表能量阈值较宽,数值波动幅度和频率的改变受环境影响更明显; (3) 城市生态系统内部及其与环境架构的地表能量关系的平衡取决于一座城市开敞空间的格局、状态和质量。     

基于ETM数据的佳木斯市地热预测研究

热红外遥感技术是地热资源调查的有效途径之一。在佳木斯市地热调查研究中,利用ETM热红外波段数据和相应的气象资料,采用单窗算法,反演佳木斯地表温度,分析了地表温度的空间分布特征和热异常状况。研究结果表明,佳木斯市区北东东约30km处存在明显的地表温度异常区,且异常区分布与隐伏断裂构造的分布有较好的对应关系,此区域为寻找地热资源的有利区域。     

A modeling of the sea breeze and its impacts on ozone distribution in northern Taiwan

A high-resolution air pollution numerical model system (APOPS) is applied to simulate the sea/land breeze and its impacts on the ozone distribution in northern Taiwan. The system can successfully simulate local flow patterns such as sea/land breezes and mountain-valley wind. The predicted surface ozone concentrations also agree with observed surface ozone values (Wang, Z., et al., Tellus, 52B, 2000, 1189). The sea/land breezes in northern Taiwan play a significant role in the distribution of ozone and transport of ozone from the urban to the coastal and mountain areas. The sea breeze is a weak system, extending vertically to a height of less than 1 km with the wind speed less than 4 ms^-1. The land breeze can transport the photochemically produced ozone and its precursors over the sea. The accumulated ozone on the sea can return to the land in the daytime with the sea breeze. This kind of transport tends to contribute significantly to high-ozone episodes in clean coastal and mountain regions.     

New 500 m spatial resolution land cover map of the western insular Southeast Asia region

This letter presents the methodology and accuracy assessment of a new 500 m spatial resolution land cover map of the western part of insular Southeast Asia. The map was produced using 250 Moderate Resolution Imaging Spectroradiometer (MODIS) images (acquired 1 January–2 July 2007), elevation information and peatland maps. The map covers the Malaysian Peninsula and the major islands of Sumatra, Java and Borneo, in addition to numerous smaller islands. The classification scheme of 12 classes reflects the special characteristics of land cover of insular Southeast Asia. With an overall accuracy of 82%, the map provides reliable new information on the current land cover distribution in this region, which is experiencing rapid land cover changes.     

基于热红外遥感的城市热场形成机制及特征分析--以成都市为例

利用LANDSAT5的TM6热红外数据和实时的地表温度，优选了一种方法进行成都市地面温度场反演，根据反演结果对成都市地表温度场分布特征进行了分析，同时定量分析了植被覆盖和水域廊道对地表温度场分布的影响，定量分析的结果对城市区域布局和规划有积极意义。     

Calibrating SLEUTH with big data: Projecting California's land use to 2100

This study investigated the spatial consistency of the SLEUTH urban growth and land use change model using a massive data set. The research asks whether SLEUTH can yield both a reliable forecast of land use in the state of California for the year 2100 CE, and an assessment of the forecast's reliability. Data were prepared, and SLEUTH calibrated for 174 tiles made by partitioning the data within the 6 California State Plane Zones. A null hypothesis that all data divisions of California would give similar calibration outcomes so that a uniform simulated rate of growth would apply to statewide future simulations was proven false by mapping and Moran's I values. Spatial autocorrelation was found to propagate forward into the SLEUTH forecasts, resulting in major differences within the state in land use change and change rates. We also explored the spatial distribution of the rules that changed pixels between land use classes, finding that almost 99% of forecast growth in California comes from outward spread from new and existing settlements. The paper concludes with an examination of the uncertainty inherent within, and displayed by the SLEUTH forecasts.