并行蚁群算法及其在区位选址中的应用

提出基于多叉树并行蚁群算法的区位选址优化方法.算法依据蚁群算法具有的并行特性,采用GPU(graphic processing unit,图形处理器)并行运算技术,对地理空间进行多又树划分,收集蚂蚁在多又树层间旅行时逐步留下的信息素信息,进行路径选优获得理想的候选解,从而为解决平面空间资源优化配置问题提供新的思路.实验结果表明,与普通蚁群算法相比,采用基于多叉树搜索的并行蚁群算法,能够发挥蚁群算法的并行特征,在短时问内求得较为理想的解,适合计算大区域的空间资源配置问题.     

Gis aided demographic analysis of sub-mountain area of indian punjab-A case study

The present study is an attempt to understand the huge demographic data using GIS at village level. Two blocks from the sub-mountain Siwalik region of Punjabviz. Mahalpur and Garhshankar were selected. Various thematic maps were prepared using this technique. The inequality of distribution between various parameters has been studied using Lorenz curve and Ginni coefficient. Both Mahalpur and Garhshankar blocks are moderately populated blocks with highest population in south western parts. Population density is highest in the areas adjacent to the Garhshankar and Mahalpur towns. Schedule caste population is well distributed in both the blocks. The average sex ratio of the study area is 910 females per thousand males which shows that it is not a female deficit area. There are various villages in these blocks which have sex ratio more than 1000 females per thousand males, which is quite a good sign for these blocks. The literacy rate of the study area is nearly 57 per cent, which is quite low as compared to district Hoshiarpur having 81.4 per cent. Comparatively, Mahalpur block has more literate persons as compared to Garhshankar block. Lorenz curve shows that literate persons are quite evenly distributed. NRI families were around 10 per cent of the total number of families out of which 8 per cent are in Mahalpur block while remaining 2 per cent are in Garhshankar block. The study brings out important inferences at the village level by way of pinpointing the exact location of hot spots where action is needed by the planners and the administration.     

室内位置信息模型与智能位置服务

商业中心、交通枢纽、医院、停车场等复杂室内及地下空间的安全管理与应急响应对室内外无缝导航与位置服务的需求日益迫切,提出了一种室内位置信息模型,扩展了OGC标准CityGML和IndoorGML中的位置信息描述,提供了描述室内相对位置和室内绝对位置的本体,介绍了一种针对三维建筑物模型的室内空间自动提取方法,为智能位置服务奠定了重要基础。     

Two Approaches of Textural Classification for the Location of the Flows of Lava on the Volcanic Site of the Mountain Cameroon

Abstract

This study presents two approaches of textural classification on a synthetic aperture radar (SAR) ERS‐2 image, with the aim of the location of the flows of lava and of the serviced zones around the volcanic site of the Mountain Cameroon. The first approach is a method of progressive supervised classification, where a single class is extracted at the same moment, by using 7 parameters of texture stemming from the run length method. Three classes of texture were extracted by this method and the images from the three classes were merged by the red green blue coloured composition to produce the final map. For purposes of comparison, a not supervised classification was applied to the same image. The applied not supervised classification uses parameters of texture stemming from the co‐occurrence matrix method, and it lays on the detection of the peaks of a histogram. The results obtained by the two methods are coherent, and the validation of the results was made by observations during a recent mission on the site of study.     

Simulation Modelling Applied to Runoff Modelling Using MapScript

Dynamic spatial analysis addresses computational aspects of space–time processing. This paper describes the development of a spatial analysis tool and modelling framework that together offer a solution for simulating landscape processes. A better approach to integrating landscape spatial analysis with Geographical Information Systems is advocated in this paper. Enhancements include special spatial operators and map algebra language constructs to handle dispersal and advective flows over landscape surfaces. These functional components to landscape modelling are developed in a modular way and are linked together in a modelling framework that performs dynamic simulation. The concepts and modelling framework are demonstrated using a hydrological modelling example. The approach provides a modelling environment for scientists and land resource managers to write and to visualize spatial process models with ease.     

基于手机定位方法的研究与精度分析

对手机定位方法进行研究,通过实验采集数据,对手机定位的精度和导航的准确度进行检验。仅从GPS这种方式进行实验检测可知,手机GPS方式定位的精度在50m以内,无论是在市区还是郊区变化不大。手机以目前的精度足以满足大家出行需要。     

手机定位服务与电子地图

随着电信与移动通信公司新一代网络的开通,数据业务将变得非常重要,其中以移动用户位置为中心的信息服务成为关键内容之一。在手机定位服务中,必须通过电子地图系统将获取的终端位置转换成用户真正关心的地理信息。首先介绍了手机定位服务的概念及常用的手机定位方式的特点,分析了手机定位服务中应用布尔莎模型进行WGS-84坐标系到地图坐标系的转换方法,阐述了手机定位服务可提供的功能和手机定位服务中电子地图需要具备的功能。最后,分析了手机定位服务存在的缺点和使用中有待解决的问题。     

手机定位服务与电子地图

随着电信与移动通信公司新一代网络的开通,数据业务将变得非常重要,其中以移动用户位置为中心的信息服务成为关键内容之一.在手机定位服务中,必须通过电子地图系统将获取的终端位置转换成用户真正关心的地理信息.首先介绍了手机定位服务的概念及常用的手机定位方式的特点,分析了手机定位服务中应用布尔莎模型进行WGS-84坐标系到地图坐标系的转换方法,阐述了手机定位服务可提供的功能和手机定位服务中电子地图需要具备的功能.最后,分析了手机定位服务存在的缺点和使用中有待解决的问题.     

基于位置融合的WiFi室内定位新策略

基于接收信号强度（RSS）的WiFi室内定位技术由于其成本低、易部署的特点成为近年来的一个研究热点。基于RSS的WiFi室内定位由于受到室内环境复杂、动态变化性强的特性,位置估计精度和可靠度较低,因此本文提出了一种新的位置融合定位策略进一步改善基于RSS的WiFi室内定位的精度。新的位置估计策略融合三种AP选取策略的位置估计结果,试验结果表明,新提出的位置融合定位策略能够提高位置估计的精度,同时保证定位结果的可靠性,其整体定位性能更优。      

Modelling the Real World: Conceptual Modelling in Spatiotemporal Information System Design

Throughout the relatively young history of research on spatiotemporal modelling, a substantial number of models have been presented. However, since a spatiotemporal model represents a closer approximation to the real world than is the case for traditional models, such models must be based on a thorough understanding of how objects 'behave' in reality. One way to acquire such knowledge is using conceptual modelling methodologies . In this paper, an overview of different modelling principles and a selection of conceptual modelling languages are presented together with examples related to a selection of spatiotemporal problems.     

Location similarity of regions

This article gives a systematic investigation of location-based similarity between regular regions. Starting from reasonable conditions for such measures, it is shown that there is only a finite number of location properties to be compared. The complete set of combinations is presented, and their behaviour and interpretability are discussed.Similarity measures are needed for all kinds of matching problems, including merging spatial data sets, change detection, and generalization. However, the measures are empirical measures. Therefore, measures found in literature seem to be chosen at random. With this synopsis, I show the differences of behaviour for all available choices.     

Dynamic Modelling and Visualization on the Internet

There is a growing requirement for GIS to incorporate dynamic analytic models. At the same time, there is a need to distribute results of dynamic GIS using the Internet. Therefore, this paper sets out to explore the implementation of dynamic environmental models using Internet-based geocomputation techniques. An overview discusses shortcomings of current Internet GIS techniques for dynamic modelling based on the idea that bidirectional and sustained communication is required between the client and the server sides. Thus an applet-servlet approach is explored to demonstrate the modelling process of a chosen hydrological model, TOPMODEL, which requires frequent and efficient client-server interactions. This approach overcomes the inherent shortcomings of the current Common Gateway Interface (CGI) and more primitive Java applet techniques. We present an effective and generic way to implement dynamic modelling and visualization processes in an Internet environment. This allows users to benefit from Internet-based geocomputation techniques to gain insights into computation and representation of dynamic spatial phenomena.     

LBS中位置及其语义的研究

阐述了两种LBS位置表示方法，引入了语义位置的概念，对现有的语义位置概念作了修正。强调了位置属性也是语义位置的重要组成部分。通过对位置概念内涵和外延的分析，讨论了位置属性所包括的内容；运用层次建模，实现了位置之间关系的描述。为了能够规范化地描述语义位置，运用本体技术，对位置所包含的语义信息进行了描述，建立了能够被计算机识别和处理的OWI。位置本体模型。通过对语义位置的本体建模，实现了位置信息的知识化描述，为实现个性化服务奠定了基础。     

Location Intelligence: An Innovative Approach to Business Location Decision‐making

As one of the leading ‘world cities’, London is particularly reliant on sources of foreign direct investment (FDI). In the face of increasing global competition and a difficult economic climate, the capital must compete effectively to encourage and support such investors. Through a collaborative study with London's official FDI promotion agency, Think London, the need for a coherent framework for data, methodologies and tools to inform business location decision‐making became apparent. This article discusses the development of a rich environment to explore, compare and rank London's business neighbourhoods. This is achieved through the development and evaluation of a model for location‐based decision support. First, we discuss the development of a geo‐business classification for London which draws upon methods and practices common in geodemographic neighbourhood classification. A geo‐business classification is developed, encapsulating relevant location variables using Principal Components Analysis into a set of composite area profiles. Second, we discuss the implementation of an appropriate Multi‐Criteria Decision Making methodology, in this case Analytical Hierarchy Process (AHP), enabling the aggregation of the geo‐business classification and decision‐makers' preferences into discrete decision alternatives. Finally, we present the results of the integration of both data and model through the development and evaluation of a web‐based prototype.     

主成份检验和粗差定位

目前国内外文献中对于粗差的检验,多数是采用改正数V,主成分检验法是将V改算成为主成分W,然而对W进行统计检验。本文讨论如何应用数理统计中的主成分检验法探测粗差。此外还讨论了粗差的初步定位和最后定位的方法,提出了预测偏盖最大准则和极小极大主分量准则。     

Secure User Plane Location: concept and performance

Assisted GPS (A-GPS) has received much attention from both academic and industry because of its two major advantages, faster positioning and greater sensitivity. Secure User Plane Location (SUPL) is an emerging standard for A-GPS produced by the Open Mobile Alliance. This article briefly reviews A-GPS, then introduces the SUPL architecture and explains how SUPL works. An intensive SUPL A-GPS survey under different environments is reported in detail, while a standalone GPS test was utilized for comparison. The survey was carried out in 24 locations over the University of New South Wales campus representing 5 types of terrain: Urban, Suburban, Rural, Indoor, and Open sky with a wide range of acquisition difficulty levels. The results show SUPL can bring a great benefit in fast positioning—much shorter Time-To-First-Fix and high sensitivity—and a much lower failure rate.     

多维粗差的同时定位与定值

提出了多维粗差同时定位定值的方法(LEGE法),它不仅能确定k个粗差的位置(k≤r-1,r为多余观测数),而且可以同时求出这些粗差的大小,从而开辟了粗差定位定值的一条新途径。