基于RIA模式的地理信息服务平台建设

随着Internet日益成为GIS开发和应用的默认平台,WebGIS的复杂性越来越高。介绍富客户端的应用模式在面向服务的地理信息平台开发中的作用。针对当前GIS平台的建设情况,利用RIA技术结合REST服务在地理信息展示、更新与管理方面的优势,提出RIA服务平台设计及应用模式,并给出一些典型应用案例。     

基于客户端插件体系结构的RIAWebGIS框架原理和实现

WebGIS与RIA(Rich Internet Applications)技术的结合,可以提高系统的交互性和用户体验。但目前,缺乏一个RIA WebGIS下的简洁高效的应用框架体系结构,以适应GIS系统与越来越复杂的业务系统的集成。在研究WebGIS的技术特点与分析现有RIA WebGIS框架基础上,提出一种面向前端插件体系结构的RIA WebGIS开发框架,并对该框架的模型层次和关键技术进行了剖析,最后将此框架应用于实际应用系统,验证了该框架的高效性和可扩展性。     

基于RIA的GeoWeb实现研究

分析了目前WebGIS所存在的问题,并探讨WebGIS和GeoWeb的异同,同时介绍了RIA的有关情况,并据此提出了基于RIA构建GeoWeb的思路。在分析这种方案理论可行性的基础上,着重介绍了RIA环境下Ge-oWeb的体系结构以及实现的关键技术,研究表明RIA技术在开发高交互性GeoWeb方面具有可行性。最后,建立一种在多个应用程序中都能重用的通用服务,并使用RESTful的Web服务简单标准集。最终实现一个基于RESTful的SOA架构的Geoweb应用,在Flex和ArcGIS Server平台上给出实现和体验。     

WebGIS开发中的RIA技术应用研究

作为当前Web地理信息系统开发的新技术,RIA较之HTML可实现的接口更健壮、反应更灵敏并且可实现更令人感兴趣的可视化特性。在介绍RIA技术的内容及其特点基础之上,探讨其与WebGIS集成开发的可行性,阐述RIA技术在WebGIS工程开发中的应用实例。     

基于WebGIS的突发事件网络舆情可视化设计与实现

从地理学角度分析网络舆情,将网络舆情映射到地理空间,借助GIS地理可视化及空间分析技术来分析和挖掘网络舆情的时空特性。设计了基于RIA模式架构的分布式突发事件网络舆情WebGIS平台,实现了基于事件的网络舆情时空可视化、专题图制作、空间分析和预测预警等功能,为突发事件应急处置、知识发现提供决策支持。     

基于Silverlight的工业经济地理信息系统设计与实现

为了提高WebGIS响应效率,满足用户对高交互性和炫酷界面的需求,提出采用RIA（丰富互联网应用程序）技术改善WebGIS传统结构模式存在的问题,介绍各种RIA技术并对比总结其优缺点,详细分析新兴的微软Silverlight技术特点,针对应用系统功能需求,利用Silverlight技术在ArcGISServer10平台上设计并实现基于RIA的成都市工业经济GIS系统,验证Silverlight在WebGIS富客户端的可行性。     

基于Flex的WebGIS客户端及其应用

通过对RIA技术与Flex开发模型的介绍,分析了基于Flex的WebGIS客户端框架层次结构及其相互之间的关系,并以武汉市直管公房地理信息系统为例,实现了Flex框架下WebGIS客户端的构建。     

基于Flex技术的WebGIS开发新模式

依据Flex RIA的技术特点,探讨了基于Flex的RIA WebGIS开发新模式,构造出了一个实用的RIAWebGIS应用开发框架,并引入ArcGIS Server10分布式系统及Flex桌面端程序模块化以提高系统效率,最后据此提出系统设计方案,开发了某市的工业地理信息管理系统。结果表明,利用Flex技术开发富用户体验的富客户端WebGIS是一种理想的方式。     

基于Flex的WebGIS应用框架研究

WebGIS即万维网地理信息系统,WebGIS本质上属于GIS的一种技术手段,它利用了交互网络技术,完成了扩展和完善地理信息系统的的功效。富因特网应用程序(Rich Internet Applications,RIA)的出现为基于万维网的地理信息应用提供了更加丰富的数据模型和更加丰富的界面元素,极大地增强了用户的体验。微软出品的SilverLight软件、Adobe推出的Flex软件都是RIA客户端的开发框架的代表。本文主要研究讨论基于Flex的两种WebGIS应用框架。     

浅谈基于Flex RIA与REST的WebGIS研究

WebGIS是GIS技术和Web技术结合的产物,近年来得到极大发展,但是随着人们对WebGIS要求的不断提高,WebGIS在应用中暴露出了反应速度慢、交互性差、用户体验性不高等缺点,文章通过对以Flex为代表的RIA技术和REST风格的研究,设计了WebGIS系统框架,在此基础上开发了一个试验系统,实验结果表明利用RI...     

阿克苏河-塔里木河水系水质污染遥感监测与评价

 采用Landsat TM数据分析了阿克苏河—塔里木河断面水质污染状况,通过波段的DN值和常规监测数据建立能反映水质状况的 污染物监测模型。结果发现,将2000年常规监测数据代入模型后,与遥感数据的结果基本吻合| 重建阿克苏河—塔里木河的连续水体 污染变化曲线,得出污染物浓度随着远离上游而增加。     

Monitoring drought dynamics in the Aravalli region (India) using different indices based on ground and remote sensing data

The hard-rock hilly Aravalli terrain of Rajasthan province of India suffers with frequent drought due to poor and delayed monsoon, abnormally high summer-temperature and insufficient water resources. In the present study, detailed analysis of meteorological and hydrological data of the Aravalli region has been carried out for the years 1984–2003. Standardised Precipitation Index (SPI) has been used to quantify the precipitation deficit. Standardised Water-Level Index (SWI) has been developed to assess ground-water recharge-deficit. Vegetative drought indices like Vegetation Condition Index (VCI) and Temperature Condition Index (TCI) and Vegetation Health Index (VHI) have been computed using NDVI values obtained from Global Vegetation Index (GVI) and thermal channel data of NOAA AVHRR satellite. Detailed analyses of spatial and temporal drought dynamics during monsoon and non-monsoon seasons have been carried out through drought index maps generated in Geographic Information Systems (GIS) environment. Analysis and interpretation of these maps reveal that negative SPI anomalies not always correspond to drought. In the Aravalli region, aquifer-stress shifts its position time to time, and in certain pockets it is more frequent. In comparison to hydrological stress, vegetative stress in the Aravalli region is found to be slower to begin but quicker to withdraw.     

使用FME与VBA提取机场方格网高程数据

因受机场工程设计软件的测量数据容量限制,基于LiDAR采集、点云分类后得到的地面点云数据LAS不能完整应用于目前设计软件进行设计计算。本文通过对拟选技术方案的筛选,提出了利用FME Workbench数据处理功能,结合VBA编程获取外部方格网平面数据的方法。该方法在FME Workbench中实现了地面点云数据构建TIN、采用逐点内插方法从TIN中提取方格网高程数据、等高线生成及相应图形处理与成果输出。最终通过实际算例证明了该方法的有效性。     

Landslide risk analysis between Giri and Tons Rivers in Himachal Himalaya (India)

The area around Sataun in the Sirmur district of Himachal Pradesh, India (falling between the rivers Giri and Tons; both tributaries of the Yamuna River) was studied for landslide vulnerability on behalf of the inhabitants. The study was made using extensive remote sensing data (satellite and airborne). It is well supported by field evidence, demographic and infrastructural details and aided by Geographic Information System (GIS) based techniques. Field observations testify that slope, aspect, geology, tectonic planes, drainage, and land use all influence landslides in the region. These parameters were taken into consideration using the statistical approach of landslide hazard zonation. Using the census data of 1991, vulnerability of the populace to the landslide hazard was accessed. As most of the infrastructure in the region is concentrated around population centres, population data alone was used for vulnerability studies.     

Gravity Changes Before Large Earthquakes in China: 1998-2005

Although it is well known that coseismic gravity changes take place during an earthquake, previous research has not yielded convincing evidence demonstrating that significant gravity changes occur before large earthquakes. Furthermore, even if we suspect that gravity changes occur before large earthquakes, we have yet to demonstrate how to consistently observe these changes for useful earthquake forecast that would bring benefits to society. We analyzed ground gravity survey data obtained in 1998, 2000, 200...     

GNSS系统及其技术的发展研究

阐述了国际上卫星导航系统的总体发展,对美、俄、欧、中的四大全球系统,以及相关的区域系统和增强系统进行了简单的介绍,研究分析了GNSS系统及其技术的发展趋势,同时分析了我国Compass全球系统面临的机遇和挑战,并提出了我国未来工作的建议.     

“4D”技术及其应用

介绍“４Ｄ”（即数字地面模型、数字正射影像、数字栅格地图和数字线划地图）系列产品的生产流程、关键技术、及其在耕地保护、防灾减灾救灾和城市规划等方面的应用方法。     

Virtual Australia: its key elements – know,think, communicate

Abstract

Virtual Australia is not a well-defined or agreed concept. This discussion paper conceptualises Virtual Australia as a ‘virtual [digital] model containing and representing all non-trivial objects and their contextual environment – from blue sky to bedrock – in real world Australia’. It describes a scenario for Virtual Australia, one or two decades from now, in which the locations and conditions of non-trivial objects and their environment are updated automatically through a combination of remote sensing and wireless communication technologies in support of a ‘Supranet’. It then examines the concept of the ‘Supranet’ – a pervasive information network based largely on wireless technology linking the physical world to a virtual model in real time – and develops and discusses three principal characteristics of the Supranet: the ability to have or collect specific information (know); the ability to process information (think); and the ability to communicate that information. If, in the near future, any or all non-trivial devices are to some extent able to know, think and communicate, the potential for object autonomy will be realised.     

自动车辆定位导航系统中传感器的误差分析

对国界定位导航系统中几种常见的辅助传感器所产生的误差进行了分析，导出了不同传感器的误差模型。这些误差模型是估计车辆位置的扩展卡尔曼滤波器的基础，同时也为选择适当的传感器提供了理论根据。