Synchronising geometric representations for map mashups using relative positioning and Linked Data

Map mashups, as a common way of presenting geospatial information on the Web, are generally created by spatially overlaying thematic information on top of various base maps. This simple overlay approach often raises geometric deficiencies due to geometric uncertainties in the data. This issue is particularly apparent in a multi-scale context because the thematic data seldom have synchronised level of detail with the base map. In this study, we propose, develop, implement and evaluate a relative positioning approach based on shared geometries and relative coordinates to synchronise geometric representations for map mashups through several scales. To realise the relative positioning between datasets, we adopt a Linked Data–based technical framework in which the data are organised according to ontologies that are designed based on the GeoSPARQL vocabulary. A prototype system is developed to demonstrate the feasibility and usability of the relative positioning approach. The results show that the approach synchronises and integrates the geometries of thematic data and the base map effectively, and the thematic data are automatically tailored for multi-scale visualisation. The proposed framework can be used as a new way of modelling geospatial data on the Web, with merits in terms of both data visualisation and querying.     

Formal representation of qualitative direction

This paper reviews formal approaches to representing spatial knowledge about qualitative direction. Unlike geometric direction information, qualitative information does not employ numerical values but relies on comparison. The qualitative approach is often regarded as suitable for capturing commonsense concepts and thus is relevant to human-centered interfaces for spatial information systems. To establish a context for the work on qualitative direction, we preset a brief history of the development of qualitative temporal and spatial representations from different scientific perspectives. We identify main focal areas of these representations of spatial direction and propose a taxonomy. In the light of more than three decades of fruitful research, we obtain a map of formal representations that reveal interrelationships between different research strands in the field.     

基于专家知识的滑坡危险性模糊评估方法

滑坡发生的影响因素众多, 其危险性与各因素之间的关系多呈非线性关系, 同时各因素之 间也存在或强或弱的相关性, 而目前的危险性评价方法难以体现这些要求。本文提出了一种借助 滑坡专家知识并利用模糊推理理论进行滑坡危险性评价的方法。该方法通过建立了①坡度与岩 层倾角之差和坡向与岩层倾向之差、②坡度和岩性、③临空面和岩性、④坡形和岩性等四种环境 因子组合, 以此将不同环境因子之间的相关性融入各组合模型中, 并将四种组合所得的模糊危险 度进行叠加用于滑坡危险度的模糊评价。环境组合模型中的参数利用专家经验给出。将该方法应 用于三峡库区云阳- 巫山段, 得到了滑坡危险性的分级分布图。从滑坡危险性分布图上可清楚发 现, 本方法所计算出的危险性值在滑坡发生的地区明显高于未发生滑坡的地区, 该结果可以用于 城镇建设和重要基础规划设施的参考。     

Multi-criteria modelling and clustering of spatial information

To improve the formal integration of verbally given spatial information in a geographical information system, a methodology for converting such information to a geographical representation was developed. This was applied to examples of a spatial-related analysis of natural language text messages in the domain of disaster management. This article presents an approach for such a conversion by using a suitable knowledge representation as well as formal modelling structures. The structures are provided by an ontology-supported knowledge base. With respect to spatial uncertainty, a formal representation based on possibility theory was defined. Moreover, a cluster algorithm was developed for handling information of different sources and building a spatial context.     

Environmental Rationalism and Beyond: Toward a more just sharing of power and influence

Economics, especially the narrowly defined form of economics known as neo-liberal economics, along with its policy derivative known as economic rationalism, dominates public and political debate and decision-making in Australia and many other nations as the twentieth century approaches its close. In the context of environmental issues, as also in that of welfare issues, the present over-dominance is unhealthy. Despite the best attempts of environmental economists and ecological economists, they have had relatively little influence on the broader economic profession, or on the political and business communities. Economics and free trade also dominate the international scene at the expense of equity and environmental issues. Environmental debates, by their very nature, are usually complex, requiring interdisciplinary and multidisciplinary approaches which include the economic perspective, but much else besides. Despite the importance of local context and spatial and temporal location, there is a need for a meta-theory or national philosophy to allow the integration across space and time so often needed. The present meta-theory, firmly based in economic rationalism, is inadequate as a basis for environmental decision-making. We desperately need a new meta-theory that explicitly integrates economic, environmental, welfare and many other perspectives. Perhaps such a meta-theory could be broadly based on the concept of sustainability, though much more work is needed to refine such an approach. A major swing in public opinion from the old meta-theory to the new is essential as a forerunner to political action, and education at all levels is needed to bring about this change. There are some signs that this change is already informing public opinion, and that it may have begun to influence mainstream Australian politics.     

A data‐mining approach for assessing consistency between multiple representations in spatial databases

When different spatial databases are combined, an important issue is the identification of inconsistencies between data. Quite often, representations of the same geographical entities in databases are different and reflect different points of view. In order to fully take advantage of these differences when object instances are associated, a key issue is to determine whether the differences are normal, i.e. explained by the database specifications, or if they are due to erroneous or outdated data in one database. In this paper, we propose a knowledge‐based approach to partially automate the consistency assessment between multiple representations of data. The inconsistency detection is viewed as a knowledge‐acquisition problem, the source of knowledge being the data. The consistency assessment is carried out by applying a proposed method called MECO. This method is itself parameterized by some domain knowledge obtained from a second method called MACO. MACO supports two approaches (direct or indirect) to perform the knowledge acquisition using data‐mining techniques. In particular, a supervised learning approach is defined to automate the knowledge acquisition so as to drastically reduce the human‐domain expert's work. Thanks to this approach, the knowledge‐acquisition process is sped up and less expert‐dependent. Training examples are obtained automatically upon completion of the spatial data matching. Knowledge extraction from data following this bottom‐up approach is particularly useful, since the database specifications are generally complex, difficult to analyse, and manually encoded. Such a data‐driven process also sheds some light on the gap between textual specifications and those actually used to produce the data. The methodology is illustrated and experimentally validated by comparing geometrical representations and attribute values of different vector spatial databases. The advantages and limits of such partially automatic approaches are discussed, and some future works are suggested.     

Empirical determination of geometric parameters for selective omission in a road network

Selective omission in a road network is a necessary operation for road network generalization. Most existing selective omission approaches involve one or two geometric parameters at a specific scale to determine which roads should be retained or eliminated. This study proposes an approach for determining the empirical threshold for such a parameter. The idea of the proposed approach is to first subdivide a large road network, and then to use appropriate threshold(s) obtained from one or several subdivisions to infer an appropriate threshold for the large one. A series of experiments was carried out to validate the proposed approach. Specifically, the road network data for New Zealand and Hong Kong at different scales (ranging from 1:50,000 to 1:250,000) were used as the experimental data, and subdivided according to different modes (i.e. administrative boundary data, a regular grid of different sizes, different update years, and different road network patterns). Not only geometric parameters, but also structural and hybrid parameters of existing selective omission approaches were involved in the testing. The experimental results show that although the most appropriate thresholds obtained from different subdivisions are not always the same, in most cases, the appropriate threshold ranges often overlap, especially for geometric parameters, and they also overlap with those obtained from the large road network data. This finding is consistent with the use of different subdivision modes, which verifies the effectiveness of the proposed approach. Several issues involving the use of the proposed approach are also addressed.     

Propagating radial waves of travel cost in a grid

To calculate the minimum cost of travel to each location within a geographical area from a specified set of locations, most geographic information systems represent that area as a rectangular grid of discrete cells, each indicating the cost of traversing that cell's particular location. These increments of cost are then accumulated by proceeding from cell to adjacent cell in a manner that resembles the propagation of waves. Because this propagation is limited to the eight directions associated with each cell's eight neighbors, however, it is often misdirected, and travel costs are therefore often overestimated. This article discusses the context, precedent, design, implementation, performance, and implications of a new algorithm that eliminates such problems in a straightforward manner. It does so by retaining the octangular propagation mechanism of earlier algorithms while keeping track of the particular locations at which propagated waves of accumulating travel cost either refract or diffract. The approach also holds promise for significant improvement in areas ranging from dispersion modeling and shape analysis to interpolation and the delineation of cost-minimizing paths.     

Emotionally intelligent research

Key to this paper is not so much the emotions of the researcher that emanate from fieldwork, but those of the researched (and their emotional intelligence). Using a vignette of research on the impact of the 2001 foot and mouth disease outbreak on rural economies in the north of England, the paper explores emotions as clues and ways of seeing. It is broadly influenced by a social constructionist approach that views emotion as created and understood in the context of relationships with others and made meaningful through discourses, language and signifiers. It does not, though, deny the physical sensations that accompany emotion and the ways in which emotions are embodied as individuals interact with others (human and non-human).     

行为地理学研究的方法论问题

行为地理学研究正成为人文地理学的一大热点。时代呼唤具有中国特色的行为地理学研究理论与方法。文章探讨行为地理学研究中的方法论问题,强调微观个体行为与整体社会的结合、短期行为与长期行为的结合、主观能动性与客观制约的结合、定量研究与质性分析的结合等,并试图提出一个行为研究的整体性框架。     

Where's the Fire? Co-Constructing Bushfire in the Everyday Landscape

This research studied factors that residents of a fire-prone Victorian community used when deciding whether to leave their homes on a day officially declared “Catastrophic,” the highest Fire Danger Rating. Taking a social constructivist perspective, we explore how the expert view of bushfire risk, represented by Fire Danger Ratings, is interpreted within the context of local understandings of the landscape and social memory of bushfire. Residents perceive a disconnection between the Fire Danger Rating and local reality. Their social construction of bushfire is related to social and ecological memory, which comprises physical experience of the landscape and local fire knowledge narratives. The exclusion of this social complexity from Fire Danger Ratings diminished their utility as a way of helping people make meaning of bushfire. We propose that fire management agencies work with communities to develop a co-constructed view of bushfire risk that incorporates local bushfire knowledge into Fire Danger Ratings.     

创新政策环境对外商直接投资区位选择的影响——以珠江三角洲核心区六市为例

外商直接投资（FDI）企业按知识基础类型可分为解析型、合成型和象征型,从政策工具维度对珠江三角洲核心区六市2007—2016年的创新政策进行文本分析,以创新政策强度和创新政策协同度两个指标量化评估珠三角核心区六市创新政策环境,利用多项式逻辑回归模型识别和检验创新政策环境对异质性知识基础的外商直接投资企业区位选择的影响。结果表明：① 珠三角核心区六市创新政策环境时空分异显著,以2010年为时间节点创新政策强度显著提升而协同度明显降低,创新政策强度与协同度均呈楔形空间结构但二者空间异构明显;② 创新政策强度和创新政策协同度对FDI区位选择皆有显著的正效应,且随着创新政策协同度的提升区域更有可能成为解析型和合成型FDI区位选择的对象;③ 政府态度、企业进入方式和布局区位对FDI区位选择有显著影响,集聚因素中的商务服务水平对FDI区位选择的影响显著为正,而城市人口密度和集聚经济水平的影响显著为负。研究结果对地方政府实施更加本地化的创新政策吸引差异化知识基础的FDI,构建区域竞争优势带来重要启示。     

Getting by: The ethnomethods of everyday cycling navigation

Cycling is often carried out in public places, meaning that it is easy to both observe and video-record cycling in action. Within sociology, ethnomethodology focuses on practical activities, often by collecting and analysing video data. Geographers have also used video data in researching cycling, but the two perspectives have little crossover. This article showcases an ethnomethodological analysis of video data on everyday cycling navigation, presenting three empirical examples. We see that cycling, accomplished by real interacting people, needs analysing in fine detail. Further knowledge of the mundane aspects of cycling mobility can usefully build upon such a videographic approach.     

KBGIS-II A knowledge-based geographical information system

Abstract

This paper describes the architecture and working of a recently implemented knowledge-based GIS (KBGIS-II) that was designed to satisfy several general criteria for GIS. The system has four major functions, query-answering, learning, editing and training. The main query finds constrained locations for spatial objects that are describable in a predicate-calculus based spatial object language. The main search procedures include a family of constraint-satisfaction procedures that use a spatial object knowledge base to search efficiently for complex spatial objects in large, multi-layered spatial data bases. These data bases are represented in quadtree form. The search strategy is designed to reduce the computational cost of search in the average case. The learning capabilities of the system include the addition of new locations of complex spatial objects to the knowledge base as queries are answered, and the ability to learn inductively definitions of new spatial objects from examples. The new definitions are added to the knowledge base by the system. The system is currently performing all its designated tasks successfully, although currently implemented on inadequate hardware.     

人文地理学的“神经转向”研究进展及启示

“神经转向”是在后现代语境下提出的,运用神经机制诠释人的心智与空间的关系,超越“社会文化”与“生物神经”的边界,强调情感、身体、“非理性”等的主体特征,为人文地理学研究提供了新的认识论和方法论。同时,人文地理学研究的“空间传统”有益于对批判神经科学关于“心智—大脑—环境”的理解产生知识溢出,实现学科交叉的良性循环。论文梳理了国内外涉及神经科学理论与方法的人文地理学研究,基于具身认知和非表征理论分析人文地理学中“神经转向”研究的理论基础,并围绕空间感知、情感认知、行为实践等主题进行介绍。另外,神经科学技术手段为人文地理学研究提供了新的方法,大脑成像、眼动追踪技术已经在地理学科中得到应用,呈现可期的未来愿景。最后,论文提出“神经转向”对中国人文地理学研究的理论创新和实践路径的启示。     

Quantification of spatial gradation of slope positions

Transition between slope positions (e.g., ridge, shoulder slope, back slope, foot slope, and valley) is often gradual. Quantification of spatial transitions or spatial gradations between slope positions can increase the accuracy of terrain parameterization for geographical or ecological modeling, especially for digital soil mapping at a fine scale. Current models for characterizing the spatial gradation of slope positions based on a gridded DEM either focus solely on the parameter space or depend on too many rules defined by topographic attributes, which makes such approaches impractical. The typical locations of a slope position contain the characteristics of the slope position in both parameter space and spatial context. Thus, the spatial gradation of slope positions can be quantified by comparing terrain characteristics (spatial and parametrical) of given locations to those at typical locations. Based on this idea, this paper proposes an approach to quantifying the spatial gradation of slope positions by using typical locations as prototypes. This approach includes two parts: the first is to extract the typical locations of each slope position and treat them as the prototypes of this position; and the second is to compute the similarity between a given location and the prototypes based on both local topographic attributes and spatial context. The new approach characterizes slope position gradation in both the attribute domain (i.e., parameter space) and the spatial domain (i.e., geographic space) in an easy and practicable way. Applications show that the new approach can quantitatively describe spatial gradations among a set of slope positions. Comparison of spatial gradation of A-horizon sand percentages with the quantified spatial gradation of slope positions indicates that the latter reflects slope processes, confirming the effectiveness of the approach. The comparison of a soil subgroup map of the study area with the maximum similarity map derived from the approach also suggests that the quantified spatial gradation of slope position can be used to aid geographical modeling such as digital soil mapping.     

Vulnerable groups and preliminary insights into intersecting categories of identity in Laamu Atoll,Maldives

The notion of vulnerability has acquired a significant role in discussions around reducing risk and identifying vulnerable groups, which is particularly important for targeting risk‐reducing policy and practice. Through ten semi‐structured interviews with 24 stakeholders, this study collected local perceptions on the following groups considered most vulnerable in Laamu Atoll, Maldives: youth and children, women, the elderly, people with disabilities, displaced persons and migrants, and farmers. In doing this, the significance of intersecting categories of identity for understanding vulnerability emerged and was explored; an approach that is often absent or scarcely applied in studies that identify vulnerable groups in the Maldives and elsewhere. Intersections between location, youth and gender or disability, as well as gender and marital status emerged as relevant for the Laamu Atoll context. Although this study acknowledges the incompleteness of its intersectional analysis, these findings provide important preliminary insights into the role of intersectionality in shaping vulnerability experience. To enhance scholarship on vulnerability, future studies could further explore intersectionality in Laamu Atoll and the Maldives using this study as a base and also improve its practical applicability for policy and practice.