Follow the road: historical GIS for evaluating the development of routes in the Negev region during the twentieth century

ABSTRACT

At the beginning of the twentieth century, a British mapping team led by Captain S. F. Newcombe surveyed and mapped the Negev region, Sinai, and western Jordan. The map was mainly produced for military use. Consequently, it included a network of branched routes, water supplies and facilities, and topographic contours. This study used this map to examine the development of routes in the Negev region between the beginning of and until the end of the twentieth century. First, the individual sheets comprising the study area were pieced together and the accuracy of the map was evaluated. The accuracy found on the Newcombe map was 0.76 mm on the map scale, equivalent to 100.3 m. Route development during the twentieth century was then evaluated by comparing the routes digitized from the Newcombe map to digitized routes on a late twentieth-century map. The results do not reveal tremendous changes in path, shape, or number of routes. Instead, they merely indicate the natural development in their quality. This Historical GIS-based approach provided a useful technique for analyzing and comparing the line segments extracted from historical and modern maps. The implemented approach may also serve other geographical or historical studies aiming to examine the development of branched networks throughout history.     

Bertin’s forgotten typographic variables and new typographic visualization

ABSTRACT

Typographic variables were only briefly discussed by Bertin with no example applications. We review historic examples to extend Bertin’s framework with literal encoding, 10 typographic attributes, variations on scope including characters, words, phrases and paragraphs, and more layout types. We then apply the framework to Bertin’s population dataset to create 11 new typographic visualizations. The approach raises questions for new research such as readability, semantic association, interaction, and comprehension.     

A heuristic multi-criteria classification approach incorporating data quality information for choropleth mapping

ABSTRACT

Despite conceptual and technology advancements in cartography over the decades, choropleth map design and classification fail to address a fundamental issue: estimates that are statistically indifferent may be assigned to different classes on maps or vice versa. Recently, the class separability concept was introduced as a map classification criterion to evaluate the likelihood that estimates in two classes are statistical different. Unfortunately, choropleth maps created according to the separability criterion usually have highly unbalanced classes. To produce reasonably separable but more balanced classes, we propose a heuristic classification approach to consider not just the class separability criterion but also other classification criteria such as evenness and intra-class variability. A geovisual-analytic package was developed to support the heuristic mapping process to evaluate the trade-off between relevant criteria and to select the most preferable classification. Class break values can be adjusted to improve the performance of a classification.     

六安台网地震自动速报系统应用研究

介绍了六安台网地震自动速报系统的基本构成及地震自动速报系统的软件构架和数据流程,并描述了安卓系统智能终端接收速报信息后,与Baidu地图在线链接,以实现区域台网地震自动速报信息震中位置的Baidu地图显示,其界面清晰、便捷直观.     

龙岗金龙顶子火山空降碎屑物数值模拟及概率性灾害评估

空降碎屑物为爆炸式火山喷发产生的一种重要的灾害类型,数值模拟已成为一个快速有效地确定火山灰扩散和沉积范围的方法。本文根据改进的Suzuki(1983)二维扩散模型,编写了基于Windows环境下的火山灰扩散程序。通过对前人资料的分析,模拟了龙岗火山群中最新火山喷发——金龙顶子火山喷发产生的空降碎屑物扩散范围,与实测结果具有很好的一致性,证实了模型的可靠性和参数的合理性。根据该区10年的风参数,模拟了7021次不同风参数时金龙顶子火山灰的扩散范围,以此制作了火山灰沉积厚度超过1cm和0.5cm时的概率性空降碎屑灾害区划图。本文的研究可为龙岗火山区火山危险性分析和灾害预警与对策提供重要的科学依据。     

Diversity in Knoxville: An applied perspective

This study contributes to the literature on applied urban geography by examining spatial patterns and processes of changing racial/ethnic diversity within the intra-urban context of Knoxville metropolitan statistical area. Knoxville embraces a diverse economic set up with opportunities in high-tech research and development, manufacturing, tertiary/service-sectors, construction, as well as entertainment industry. This serves well for its continued population growth, including minorities during 1990–2009. This paper explores how the neighborhood-level socioeconomic, demographic, and built-environment characteristics relate to tract-level racial/ethnic diversity, measured by multi-group diversity score and its components. Tools such as isarithmic surface density maps, correlations, principal components and regression analyses are used to examine processes of change. Results indicate that diversity in 1990 associates with negative change whereas diversity in 2000 associates with positive change. Though overall diversity sprawls and increases during 1990–2009, diversity among non-White declines during 2000–2009 and shows spatial confinement. Regressions suggest complicated mosaics of changing neighborhoods, providing evidence of invasion-succession, filtering and resurgence of ethnic-enclaves in specific neighborhoods. Concerning the six counties of the MSA, Knox is the most diverse whereas Union the least, though the share of Hispanics tops in Loudon and Asians in Knox. In terms of strategic planning, findings from this research can be used in creating equitable and sustainable urban communities that can improve the overall well-being of people by reducing racial/ethnic and socio-economic disparities that might occur as undesirable consequences of fast increasing diversity.     

The feasibility of a land information system for Belize,Central America

Abstract

Limitations of the current land records systems in Belize, Central America, led leaders of the Ministry of Natural Resources to initiate this feasibility study for a computer-aided land information system (LIS). Land records in Belize have been based on the British Torrens land tenure system, which maintains five sets of records along with informative maps. One paper file is maintained for each title application and records are continually circulated between seven locations throughout the country, resulting in up to 3 years to complete the process of title registration. A LIS will permit quick access to land records and eliminate most of the current problems, and will merge with a geographic information system being developed for Belize.     

A Review of: “Geographic Information Systems for Geoscientists—Modelling with GIS”

Distances from points to closest shorelines in a given direction are used, for example, in some models for estimating wave exposure. Such distances, also called fetch lengths, can be determined using standard geographic information systems. However, performance may be a problem if these distances are required for a great number of study points. Two new algorithms for determining fetch lengths for study points in the same directions are presented in this paper. It is assumed that the two‐dimensional map is stored in vector format, i.e. shorelines of islands and mainland are stored as polygons. The first algorithm works on a set of undirected line segments derived from the shoreline polygons. The other works on a raster representation of the map. The algorithm saves memory by postponing the rasterisation until necessary. Both of the new algorithms have superior efficiency to a previously reported algorithm when the number of study points is large.     

Testing the effects of positional uncertainty on spatial decision‐making

There is now increasing agreement that the uncertainty associated with spatial information should be represented to users in a manner that is comprehensive and unambiguous. To assist with this task, researchers have developed a variety of methods to portray spatial uncertainty. While there has been some testing of the effectiveness of these displays, the possible effects of such representations on decision‐making have not yet been thoroughly investigated. Indeed, studies from the psychological literature indicate that people do not always make the same decisions when presented with the same information, and they can also be sensitive to the effects of presentation, task, and context. This paper examines how the use of four different methods to represent positional uncertainty can affect spatial decision‐making. The authors found that extremely significant differences in participants' responses were exhibited, depending on the manner in which positional uncertainty was displayed, although little difference was observed in the ability of the participants to comprehend the four display methods. In addition, strong preferences were recorded for certain representations over others.     

Interest in intermediate soft-classified maps in land change model validation: suitability versus transition potential

This study compares two types of intermediate soft-classified maps. The first type uses land use/cover suitability maps based on a multi-criteria evaluation (MCE). The second type focuses on the transition potential between land use/cover categories based on a multi-layer perceptron (MLP). The concepts and methodological approaches are illustrated in a comparable manner using a Corine data set from the Murcia region (2300 km², Spain) in combination with maps of drivers that were created with two stochastic, discretely operating, commonly used tools (MCE in CA_MARKOV and MLP in Land Change Modeler). The importance of the different approaches and techniques for the obtained results is illustrated by comparing the specific characteristics of both approaches by validating the suitability versus transition potential maps to each other using a Spearman correlation matrix and, between the Corine maps, using classical ROC (receiver operating characteristic) statistics. Then, we propose a new use of ROC statistics to compare these intermediate soft-classified maps with their respective hard-classified maps of the models for each category. The validation of these results can be beneficial in choosing a suitable model and provide a better understanding of the implications of the different modeling steps and the advantages and limitations of the modeling tools.