土地划拨中基于网状的时空数据模型研究

在分析时空数据模型原理与土地划拨中时空数据特点的基础上,提出了能显式表达时态关系的网状模型,描述了该模型的基本思想,并在实验基础上分析了其特点.     

基于历史拓扑和描述子的时空数据模型

针对已有时空数据模型在表达时空信息上存在的问题,提出基于一个新的历史拓扑和描述子的时空数据模型STORM.STORM采用结合显式表达和隐式表达的混合型方法来表示时空信息,其中历史拓扑显式表达时空对象间的历史关联,而描述子隐式表达单个时空对象的内部属性变化以及时空对象间的空间拓扑关系.该模型可以同时表达时空信息的静态语义和动态语义,并可通过扩展的关系结构和关系代数操作进行表示和查询.     

基于框架的时空对象模型研究

空间数据模型反映现实世界中空间实体及其相互间的联系,但现有G IS数据模型主要表达某一时刻的空间实体及其相互之间的联系,没有考虑表示空间实体的时空变化,本质上是非时态的,无法满足各种用户的需求。本文分析了G IS应用的过程本质,系统地研究了地理信息系统过程建模的概念和类型,讨论了过程模型中的地理时空概念、空间数据模型的研究现状和存在的问题,以空间系统理论为依据,提出了空间数据模型结构,设计了适于表达G IS过程模型的基于框架的时空对象数据模型,并探讨了空间对象的时态表示和处理操作。     

时空数据模型的N1NF关系基础

Ｎ１ＮＦ关系方法在处理非表格化的复杂结构对象时优于传统关系方法，因而适合于时态ＧＩＳ。本文讨论了空间对象的Ｎ１ＮＦ表达和操作，将空间，时间和属性结合为一个整体，与作者的前期工作一起构成了矢量式时空数据模型的Ｎ１ＮＦ关系基础；本文还初步讨论了建立在这个基础上的面状地理要素的时空数据模型。     

时空拓扑关系定义及时态拓扑关系描述

目的，国际上对于作为时空数据模型概念和形式化基础的时空拓扑关系定义和描述还没有一个明确的阐述。本文在分析ＧＩＳ的时空特性后，给出了一个语义层时空拓扑关系定义。同时，提出并证明了完备、唯一的描述时态拓扑关系的４Ｉ框架，列出了时态拓扑关系描述的谓词集，区别了时态拓扑关系和时间方向关系的内涵和谓词描述形式。     

时空拓扑关系的集成表达

针对地理实体之间的时空拓扑关系,阐述了当前被普遍接受的空间和时态拓扑关系模型、基于点集和逻辑谓词集的描述方法。基于8种时态和空间拓扑关系逻辑谓词,提出时空数据库中时空拓扑关系集成表达(或称联合表达)的64种情况,分别利用英文缩写字母和关系图2种形式对其进行了描述。最后,通过示例的应用说明时空拓扑关系集成表达的具体情形。     

房产测绘信息管理的实用时空数据模型

本文在分析了房产数据的类型、及其时空变化方式与特点的基础上。利用时态对象模型和时态关系模型各自的优势，构造了房产对象-关系复合时空数据模型。在该模型的基础上，还探讨了时态查询、房产动态变化分析等问题。     

面向对象的规划道路中线时空数据模型

回顾了两种类型的时空数据模型，发展了面向对象的规划道路中线时空数据模型，进一步实现了对规划道路中线对象的查询及更新维护。该模型具有充分利用GIS已有的空间分析和方便实现时态分析的功能，同时也具有数据维护和历史数据恢复方便简单，空间信息没有冗余，时态信息冗余小，且能表达变化原因等特点。     

基于地理事件的时空数据模型及其在土地利用中的应用

本文通过分析基于位置和基于对象的空间数据表达方法的特点,顾及与空间相关的属性与地理实体空间特征之间的相依关系,将“地理事件”引入模型,提出一种顾及“隐含”地理事件和“显式”地理事件的时空数据模型(GESTDM模型).本文提出的模型能够同时提供基于位置、基于对象和基于时间的时空表达和查询功能.将该模型应用于土地利用领域,...     

时空数据模型探析

描述了时空数据模型的定义及其发展现状,通过介绍时空数据模型分类的情况、时空集成的时空数据模型与地理信息的时态性分析,丰富了时空数据模型理论。最后对时空数据模型的将来发展方向做出了一些展望。     

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.     

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.     

Toward seamless indoor-outdoor applications: Developing stakeholder-oriented location-based services

Location-Based Services (LBS),an emerging new business based on smartphone and mobile networks,are becoming more and more popular.Most of these LBSs,however,only offer non-seamless indoor/outdoor applications and simple applications without giving stakeholders the chance to play an active role.Our specific aim is to solve these issues.This paper presents concepts to solve these issues by expanding the Open Location Services Interface Standard (OpenLS) to allow seamless indoor/outdoor positioning and to extend the content of the services to include information recommended by stakeholders.     

地理数据库的关系模型及其实现

本文从以图论观点分析地理实体入手,系统阐述了地理数据库关系模型的设计法和过程。作者于1984年4～9月间在微型机上设计建立了关系型地理数据库的实方验系统(RGDB)。该系统采用了本文提出的关系模型,采用了可动态扩库的子库组合结构,这种结构具有灵活性和提高空间利用率的优点。RGDB含有多种功能的数据操作命令,除了具有一般检索功能外,还能进行“开窗”选取和十分“自由”的映象选取。本文对RGDB系统的主要性能和实现途径作了扼要介绍。     

GIS空间数据的采集误差及其分析

本文详细阐述了GIS数据采集过程中的误差来源，重点分析了通过地图、遥感和摄影测量等方式采集数据所产生的误差及其特性，分析了其对GIS数据的影响与消减方法。