The diffusion of ICT in France: infrastructures,services, and uses

How does the organization of space interfere in the numerical development of territories? Our hypothesis is that information and communication technologies (ICT) are organized by taking into account the existing spatial structures, compared to constraints of distance, spatial position and urban hierarchy. In the context of the liberalization of the sector of telecommunications, ICT spread according to an economic logic of profitability. The concern of network operators collides with the principle of territorial equity in planning policies. To understand the diffusion of ICT in France, a cartographic analysis of their distribution is proposed. It derives from the notion of networks at three levels: infrastructures, services and uses. The research takes into account the difference between regional configurations to identify the spatial factors of the digital divide. For each level, the diffusion of ICT follows a different logic, and characterizes territories with different orientations. Areas with a high density of population and activities are quickly equipped. The democratization of the use of the Internet, notably with the diffusion of public access to the Internet, is present to a greater degree in low-density areas.     

网络信息空间的城市地理学研究：综述与展望

20世纪90年代,互联网飞速发展,不仅深刻地影响了我们的社会系统和经济结构,同时也重构了全球城市的物理和虚拟空间结构形式。近几年,在西方发达国家,网络信息空间的相关研究已经成为多学科研究的热点,有关城市网络信息空间的地理学研究也不断涌现。从技术与经济的角度入手,在已有文献资料基础上,对西方地理学界关于网络信息空间与城市发展的研究进展进行了评述。首先界定网络信息空间的概念及其相对于物理空间的各种特征,然后总结城市学者研究网络信息空间的几种理论方法,并从三个空间层次分别评述现有的实证研究成果。在此基础上,对网络信息空间的测量方法和关于城市地理学的研究内容进行了进一步展望。     

Spatial variations in broadband and air passenger service provision in the United States

With the resurgence of regions as key nodes in the global economy, there is a growing interest in better defining their competitive advantages, particularly those accrued through infrastructure provision. Two important components of this competitive landscape are information and communication technologies (ICTs) and commercial air passenger service. While the development of these two networks is frequently cited as being a critical factor in regional economic competitiveness, few empirical studies address the statistical relationship(s) between these infrastructures or the complexities associated with their spatial distribution. The purpose of this paper is to determine if an association exists between the provision of broadband telecommunication service and air passenger service in the United States. In addition, basic spatial statistical approaches are utilized to identify a suite of important social and economic determinants that play a central role in spurring infrastructure provision.     

Reconceptualizing the role of the user of spatial data infrastructure

Spatial data infrastructures, which are Internet-based mechanisms for the coordinated production, discovery, and use of geospatial information in the digital environment, have diffused worldwide in the last two decades. Currently, there are about one hundred spatial data infrastructures at the national level and many other at supra- and sub-national levels. These contemporary spatial data infrastructures operate with two main assumptions: formal organizations are the producers and suppliers of geospatial information; users are the passive recipients of information. The recent phenomenon of volunteered geographic information departs from these assumptions. In this paper, we argue that reconceptualizing the user of a spatial data infrastructure can accommodate this new phenomenon. Such a reconceptualization creates a middle ground between spatial data infrastructure and volunteered geographic information, which has important implications for future research.     

基于微博平台的中国城市网络信息不对称关系研究

网络信息空间的空间关系及信息流研究为信息化影响下的地理空间演变研究奠定基础。借助微博这一新兴网络信息传播平台获取中国城市间网络信息联系数据,采用流分析方法呈现城市间网络信息联系的空间格局。研究发现:中国城市网络信息关系呈现出"一超多强"的空间极化不对称格局。网络空间不对称格局与地理距离、经济社会发展水平存在密切关联性,表现为:城市对外网络信息总不对称度与其经济社会发展水平的相对一致性;经济社会发展差距对城市间网络信息不对称程度影响的距离衰减性;城市间网络信息不对称程度与经济社会发展差距的相对一致性;东、中、西部三大地区间网络信息不对称关系与经济发展梯度的相对一致性。     

基于GIS的网络电子地图系统开发与研究

随着Internet技术的发展和人们对地理信息系统（GIS）的需求,网络上空间数据的发布,已经成为GIS的发展趋势。网络电子地图随之应运而生。我们以ArcIMs9．0作为webMap服务器,MicrosoftⅡS作Web）服务平台,结合javaScript,XML对网络电子地图系统的开发进行了探讨和研究,以合肥工业大学校园为背景,完成了的网络电子地图的系统模型构架。系统的查询、浏览、空间分析等功能齐全,使用方便。系统模型可在相关地区移植,利于推广,避免重复开发。     

The temporal stability of spatial diffusion channels

This paper attempts to answer the question of how stable are spatial channels of innovation diffusion over time. The notion of stability of diffusion channels derives from the concept of spatial autocorrelation and from the assumption that neighboring spatial units exhibit relative similarity in economic development preconditions necessary for innovation adoption. Stability, however, declines over time as the diffusion process approaches saturation. Innovations with similar properties may tend to produce similar diffusion channels, facilitating forecasting of future diffusion of innovations based on knowledge of diffusion of similar ones. A case study is provided through an analysis of the diffusion of automobiles in Ohio using three methods: visual analysis of maps of cross-sections for identification of channels, transitional matrices for analysing the nature of change in adoption situations, and surface analysis to analyse correlation between adoption surfaces in the short and long ranges. The conclusion of these analyses is that over most of the study period the channels are relatively stable in the short-range, with a general tendency of decline in stability over the long-range. A comparison to a study of diffusion of another innovation in the same area supports the assumption that channels may be more universal than innovation-specific.     

Image spaces and the geography of Internet screen-space

This article aims, first, at the exposition of image space and a scalar model differentiating among its four visual classes: virtual space (visual presentations of real space and material artifacts), cyberspace (digital communications and information media), the Internet (digital communications and informational spaces), and Internet screen-space (ISS) (users’ visual interface with the Internet), thus leading from the wider to the specific. This differentiation is followed by discussions of cyberspace and Internet screen-space geography. Cyberspace has been spatially defined as artificial reality, interactivity, and conceptual and metaphorical spaces. As a spatial experience, cyberspace involves co-presence, low cognitive mapping, and egalitarian and global communications. The article aims further at the development of interpretations for ISSs and their uses along dimensions originally developed for real-space geography. These include: real space parameters (ground; distance; places; scale/regions; boundaries; and flows); user spatial parameters (speed; directionality; circularity; distanciation); and user socio-spatial parameters (proximity; networking; time–space compression).     

A three-dimensional large-deformation random finite-element study of landslide runout considering spatially varying soil

Landslides - Landslide is a uniquely dynamic large-deformation process that can present serious threat to human lives and infrastructures. The natural soil properties often exhibit inherent spatial...     

Does the Internet encourage people to move? Investigating Swedish young adults’ internal migration experiences and plans

The Internet offers personalized and constantly updated information about opportunities and facilities at places far away. It stimulates distant personal contact and interaction via social media. Attention is thus increasingly being paid to the relationships between Internet use and traditional, physical forms of spatial interaction and movement. This paper explores possible associations between Internet use and internal migration, based on a 2009 survey of 750 young adults in Sweden. We explore Internet-based information seeking practices associated with actual migration experiences and with current plans to move to another place. Results indicate that many recent movers believed that the Internet influenced and facilitated their decision to move, and somewhat influenced their choice of destination. Many have also developed Internet-based communication practices that involve plans to migrate in the near future. Results suggest that the Internet reinforces intentions to move for a sizeable group, and also affects their migration motives.     

Research and development of advanced technologies for landslide hazard analysis in Italy

The Research Centre on Prediction, Prevention and Control of Georisks, "Sapienza Università di Roma" (CERI) was selected as one of the World Centres of Excellence on Landslide Risk Reduction (WCoE) under the title of “Research and development of advanced technologies for landslide hazard analysis in Italy” in the period 2008–2011. The present paper provides background information on the activities carried out by the CERI, in the frame of the WCoE network. Pre-defined purposes have been achieved by the implementation of integrated monitoring systems and early warning systems for landslides movements. The application of GBInSAR technique for monitoring landslides interacting with infrastructures is discussed, and two case histories are presented. It is shown that this technique is particularly suitable for the displacements monitoring of landslides interacting with infrastructures, thanks to its peculiar features (i.e. areal mapping, operability under every weather and lighting conditions and continuous and completely remote monitoring). Hence, it can be considered a very important tool for the reduction of risks connected to the realisation and activity of large infrastructures.     

面向移动空间信息服务的可移植嵌入式GIS平台

智能终端和移动互联网的快速发展使得移动空间信息服务成为数字城市和数字地球的重要内容,而各种基于定位导航的嵌入式地理信息系统(geographic information system,GIS)也逐步成为这类信息服务的主要方式.分析了现代移动空间信息服务的特征,采用层次式模块化的方法,介绍了基于GIS的可移植抽象层、多元数据存储模型、电子地图显示引擎和高性能应用服务引擎等关键模块的设计,设计了可移植的嵌入式GIS平台,为通用的移动空间信息服务移动端的应用开发提供了一个切实可行的方案.      

Towards an expanded model of curriculum development and diffusion in education

The general model of the curriculum development process has been widely accepted as a satisfactory view of the process at work and of how the process might be made to work in practice. Such a model ignores the human element. The paper expands the general model so as to include the social interaction and interpersonal dynamics dimension of curriculum change. Concepts in diffusion theory and behavioural geography provide a perspective for building into the curriculum process views of it as a social system akin in some respects to a feudal society. The expanded model includes consideration of the influence of the social, personal, psychological and attitudinal traits of those engaged in curriculum development. The spatial pattern likely to be created by the model provokes questions about the best management of the diffusion process.     

A generalized approximate analytical solution of horizontal infiltration in unsaturated soil

A generalized analytical solution for one-dimensional nonlinear horizontal infiltration in unsaturated soil is presented. The solution is an improved functional extremum method based on the principle of stationary action. Any prior assumption about the form of moisture diffusion functions is not implemented in the method. By considering a function of time, the water content type governing equation in the horizontal infiltration process is transformed into a function extremum problem. After solving the Euler–Lagrange equation, combined with boundary conditions, a linear relationship between the moisture diffusion function and the ratio of spatial location to the wetting-front distance is proposed. Furthermore, by using the square relationship between the wetting front and time, the spatial and temporal distribution characteristics of the water content profile are finally expressed. In contrast to most other work, the physical meanings of the parameters in this study are clear and can be derived explicitly. By utilizing the simultaneous Brooks–Corey moisture diffusion function, the development and distribution law of the water content profile was explicitly presented. The results of the solution matched well with the existing theoretical results of the four different soil samples. Owing to the high nonlinearity of the van Genuchten moisture diffusion function, the distribution of the water content profile was implicitly found based on the study method. The results obtained using this method were also consistent with the MATLAB routine, pdepe, numerical solutions for different types of soil properties.

     

Forecasting the HIV epidemic in Finland by using functional small area units

The purpose of this study is to analyze the development of the HIV epidemic in Finland in 1983–1994, and to predict the spatial distribution of new cases through 1997. The analysis is based on seroepidemiological data of all reported HIV carriers and a number of explaining variables based on individual level register data. Instead of focusing on populations of carriers and susceptibles, emphasis is placed on identifying the primary influences directing the epidemic as a spatial process. This is done by dividing Finland into 62 functional small area units and by assigning the risk of obtaining the virus to each unit based on behavioral, socioeconomic, interaction, and structural characteristics of the population. The approach is a multistep procedure including multivariate regression analysis, the potential model, and time series analysis. The model was used to produce a three-year forecast of the distribution of new HIV carriers in Finland. Compared with earlier studies of similar nature based on the use of administrative regional units, in this paper the forecast distribution of HIV cases is more closely related to the functional structure of the spatial system in Finland. Such an approach offers a method for producing more reliable short-term forecasts of the spatial distribution of new HIV cases. Three different spatial diffusion patterns were identified.     

Calculated phase equilibria involving chemical potentials to investigate the textural evolution of metamorphic rocks

Evolving pressure–temperature conditions during metamorphism drive changes in the stable mineral assemblage, mineral proportions and mineral compositions in rocks. These changes are achieved via the diffusion of components between minerals, fluid and melt, the driving force for diffusion being the gradients in chemical potential of the components developed spatially within the rock. This study utilises recent developments in the software thermocalc to investigate quantitatively chemical potential relationships in rocks, with the phases involved being (solid) solutions. Phase diagrams with chemical potentials as axes are used to understand better the spatial rearrangement of components during the metamorphic evolution of rocks and the metamorphic textures that result. In contrast to qualitative chemical potential diagrams, quantitative diagrams can be contoured for mineral composition, allowing consideration of chemical zoning in minerals. Furthermore, the amount of material required to diffuse to equalise chemical potentials can be calculated. We start by demonstrating the approach via an example of retrograde corona development in an ultra-high-temperature granulite. Whereas the use of chemical potentials to consider the retrograde development of corona textures is well known, they are also significant in considering the prograde history. The role of chemical potentials in prograde metamorphic textural evolution is highlighted in consideration of the consumption and growth of aluminosilicates during the kyanite-to-sillimanite reaction, and the growth of garnet porphyroblasts.     

GIS在通信行业中的应用

为阐述GIS技术在通信行业中的应用前景, 从通信行业的发展以及运行网络管理现状出发, 结合GIS技术特点阐述了GIS技术引入通信网络的管理和业务的必要性和必然性.它的引入将从根本上改变通信管线网络规划、建设、管理及资料保存等方面的传统模式, 并为通信行业实现通信全资源、跨专业管理, 为运营商提供市场分析及预测、网络规划、工程设计、资源配置和分析、线路实时监控、应急保障等方法和手段.      

Spatiotemporal analyses of religious establishments in coastal China

This research examines the diffusion process of the religious institutions of Buddhism, Daoism, and Christianity in coastal China, using the case study of Zhejiang Province since 1949. The spatial distribution dynamics and diffusion process associated with the religious establishments are presented and discussed in the GIS environment. The results reveal that the development of the religious establishments followed a hierarchical diffusion process. In addition, spatiotemporally significant agglomerations of the studied religious institutions are successfully detected.     

浅层地温场连续监测和高精度模拟时空误差研究

为探究浅层地温场的时空演化规律,综合使用多种温度传感器,获得了南京市3个钻孔0~100 m的连续高精度温度数据。采用不同精度的地层模型和上边界温度条件,开展了3个月时间尺度的地温数值模拟,分析了地温在模拟时间内时空变化规律和模拟精度。相对于平均热扩散系数,采用分层热扩散系数时提高了浅部0~4 m模拟温度的精度,降低误差为2%~4%;与高精度边界模拟结果相比,边界为日均温度时的模拟结果相差不大,而月均温度降低了0~5 m模拟温度的精度,增大误差为2%~3%,但对于均质地层影响深度较小。对于浅地表变温层处的地温模拟,在浅部0~5 m处使用分层热扩散系数,以日均温度作为边界条件能够在保证结果准确的前提下减少监测成本。文章也为南京市浅层地温长期预测和评价提供了参考。