180 research outputs found

    The Semantics of Extensive Quantities within Geographic Information

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    The next generation of Geographic Information Systems (GIS) is anticipated to automate some of the reasoning required for spatial analysis. An important step in the development of such systems is to gain a better understanding and corresponding modeling practice of when to apply arithmetic operations to quantities. The concept of extensivity plays an essential role in determining when quantities can be aggregated by summing them, and when this is not possible. This is of particular importance to geographic information systems, which serve to quantify phenomena across space and time. However, currently, multiple contrasting definitions of extensivity exist, and none of these suffice for handling the different practical cases occurring in geographic information. As a result, analysts predominantly rely on intuition and ad hoc reasoning to determine whether two quantities are additive. In this paper, we present a novel approach to formalizing the concept of extensivity. Though our notion as such is not restricted to quantifications occurring within geographic information, it is particularly useful for this purpose. Following the idea of spatio-temporal controls by Sinton, we define extensivity as a property of measurements of quantities with respect to a controlling quantity, such that a sum of the latter implies a sum of the former. In our algebraic definition of amounts and other quantities, we do away with some of the constraints that limit the usability of older approaches. By treating extensivity as a relation between amounts and other types of quantities, our definition offers the flexibility to relate a quantity to many domains of interest. We show how this new notion of extensivity can be used to classify the kinds of amounts in various examples of geographic information

    Wayfinding for cycle highways: Assessing e-bike users’ experiences with wayfinding along a cycle highway in the Netherlands.

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    In many regions, governments are motivating increased bicycle ridership by designing new and improving existing bicycle infrastructure. Cycle highways are an effective and cost-efficient type of bicycle-specific infrastructure that are designed to provide a functional connection between places where people work, go to school and live. One important element of developing high quality cycle highways is the development of an effective wayfinding system which allows current, potential, and new users to clearly identify and navigate a bicycle network. The wayfinding design standards used for conventional bicycle infrastructure may not be compatible for cycle highways, which encourage cyclists to travel at relatively higher speeds. This may warrant introducing specific wayfinding signage compatible for this new type of bicycle infrastructure. This study uses qualitative analysis including field observations, ride-along videos, and semi-structured interviews, to assess electrically assisted pedal bicycle (e-bike) users' opinions and experiences with wayfinding signage along a pilot cycle highway route located between Tilburg and Waalwijk in the Netherlands. In the summer of 2018, base-line observations and interviews were administered with twelve e-bike users who were unfamiliar with the route to assess their experiences with conventional signage for cyclists before changes were made to the wayfinding system. Follow-up observations were held in the fall, after the installation of two new pilot wayfinding systems that were specifically designed to accommodate cycle highway users. Initial findings suggest that the changes made to the location, size and clarity of the signage improve cyclists' overall experiences, and that cyclists' perceptions of the built environment are important. Specifically, it became easier for users to navigate the route, their overall travel related stress decreased, and several participants perceived shorter travel times. Policy makers and transportation planners are likely to be interested in the results of this study as they reveal how specific improvements to wayfinding along cycle highways not only help improve navigation, but also positively influence cyclists' overall comfort and stress

    Six GIScience Ideas That Must Die

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    In 2015, John Brockman edited a volume of chapters contributed by leading thinkers from various domains discussing common scientific ideas hindering further scientific progress. While starting with the provocative slogan of This Idea Must Die, the book’s chapters and their authors (for most parts) do not argue that those existing – often foundational scientific theories from various domains – are false, but instead that their widespread, and often unquestioned, utilization has started to hinder the evolution of new theories. Through this work, we would like to foster a similar discussion in our community, by suggesting six ideas in GIScience/geoinformatics that may benefit from retiring to make room for new perspectives. Our suggestions are somewhat controversial, and readers are encouraged to keep an open mind

    Environmental vulnerability assessment of Brazilian Amazon Indigenous Lands

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    Amazonian Indigenous Lands (ILs) are human-environment systems facing a multitude of environmental threats. Yet, the resulting vulnerability of these systems are to date unknown. We adopt the theoretical vulnerability framework of the IPCC to assess the environmental vulnerability of Brazilian Amazon ILs for two periods (2001–2010 and 2011–2019) and overall (2001–2019). Vulnerability is deemed a function of exposure (EX), sensitivity (SE) and adaptive capacity (AC) of a system to threats. Sensitivity (threats within IL) and exposure (threats in IL's buffer zones) indicators are changes in forest cover, economic activities, and road access, quantified using data of deforestation, forest degradation, land-use, fire, roads and mining. Adaptive capacity indicators represent Indigenous self-organization, education and access to knowledge, land ownership, external incomes, and institutional arrangement. We find a concentration of ILs with high vulnerability in the Arc of Deforestation and South, and advancing in Pará and Roraima states. A strong relationship (Spearman r = 0.79) between EX and SE indicates the strong pressure exerted by external processes. An increase in EX (73.9% of the ILs) and in SE (64.8% of the ILs) in 2011–2019 compared to 2001–2010 signals a worrying rise in vulnerability recently. We advise the adoption of policies by the State, such as combating illegal activities, and strengthening National Policy for Environmental and Territorial Management of ILs. Herein, our vulnerability quantification can prioritize help to certain ILs, and the understanding of the contribution of the underlying dimensions can direct these policies, possibly according to the vulnerability profile of each IL

    Empirical Evidence for Concepts of Spatial Information as Cognitive Means for interpreting and using Maps

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    Due to the increasing prevalence and relevance of geo-spatial data in the age of data science, Geographic Information Systems are enjoying wider interdisciplinary adoption by communities outside of GIScience. However, properly interpreting and analysing geo-spatial information is not a trivial task due to knowledge barriers. There is a need for a trans-disciplinary framework for sharing specialized geographical knowledge and expertise to overcome these barriers. The core concepts of spatial information were proposed as such a conceptual framework. These concepts, such as object and field, were proposed as cognitive lenses that can simplify understanding of and guide the processing of spatial information. However, there is a distinct lack of empirical evidence for the existence of such concepts in the human mind or whether such concepts can be indeed useful. In this study, we have explored for such empirical evidence using behavioral experiments with human participants. The experiment adopted a contrast model to investigate whether the participants can semantically distinguish between the object and field core concepts visualized as maps. The statistically significant positive results offer evidence supporting the existence of the two concepts or cognitive concepts closely resembling them. This gives credibility to the core concepts of spatial information as tools for sharing, teaching, or even automating the process of geographical information processing

    The potential of food environment policies to reduce socioeconomic inequalities in diets and to improve healthy diets among lower socioeconomic groups: an umbrella review

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    Socioeconomic inequalities in diets need to be tackled to improve population diets and prevent obesity and diet-related non-communicable diseases. The potential of food environment policies to reduce such inequalities has to date however not been appraised. The objective of this umbrella review was to assess the impact of food environment policies on socioeconomic inequalities in diets and to identify knowledge gaps in the existing literature, using the Healthy Food Environment Policy Index as a conceptual framework. The policies considered in the umbrella review are within six domains: 1) food composition 2) food labelling 3) food promotion 4) food provision 5) food retail 6) food pricing. A systematic search for systematic literature reviews on the effect of food environment policies on dietary-related outcomes across socioeconomic groups and published in English between 2004 and 2019 was conducted. Sixteen systematic literature reviews encompassing 159 primary studies were included, covering food composition (n = 2), food labelling (n = 3), food provision (n = 2), food prices (n = 13) and food in retail (n = 4). Quality assessment using the “Assessing the Methodological Quality of Systematic Reviews” quality rating scale showed that review quality was mainly low or critically low. Results suggest that food taxation may reduce socioeconomic inequalities in diets. For all other policy areas, the evidence base was poor. Current research largely fails to provide good quality evidence on impacts of food environment policies on socioeconomic inequalities in diets. Research to fill this knowledge gap is urgently needed.publishedVersio

    Researching refugee youth

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    In this Doing geography guide, we discuss some of the ethical and methodological challenges of carrying out qualitative research with refugee and asylum-seeker youth in European cities. This is neither a guide to how to use specific research methods, nor is it a toolkit that explores the advantages or disadvantages of using specific methods over others. Instead, we consider some of the ethical, political, and methodological quandaries and challenges that have arisen in our research with young refugees and asylum seekers in the four European cities of Brussels, Amsterdam, Leipzig, and Newcastle upon Tyne. In each city, we have worked closely with arts and theatre groups, community organisations, language conversation classes and other groups; some of the insights referred to here draw from these collaborations. We provide examples of research encounters that worked well, and those where challenges arose, or queries and problems emerged. In some discussions, we deal with more practical insights that surfaced during fieldwork, whereas others are more of an open discussion. Hence, in some cases, the solutions were obvious, but in other cases they were not. We discuss how we worked through these contestations in an open and collaborative way

    De winkelstraat als wereld: Samenwerken aan een toekomstbestendig evenwicht van Amsterdamse consumptieruimten: Bevindingen na vier jaar onderzoek RAAK-PRO: "Toekomstbestendig Evenwicht, Balanceren tussen divergerende belangen

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    Hoe zorg je in Amsterdam voor een aantrekkelijk en gevarieerd winkelgebied waar zowel bewoners, bezoekers en ondernemers zich thuis voelen? Hoe komen deze verschillende belanghebbenden tot een goed functionerend, gezamenlijk beheer van winkelgebieden als een gemeenschappelijke bron met verschillende functies? Wat vraagt dit van de gemeente, hoe is haar rol daarin veranderd en hoe zien we dit terug in beleid? Actuele vragen, die al geruime tijd de gemoederen in Amsterdam flink bezighouden, en die we beantwoorden in het rapport 'De Winkelstraat als wereld’. Dit rapport is uitkomst van het vierjarig praktijkonderzoek Toekomstbestendig Evenwicht: Balanceren tussen divergerende belangen (RAAK-PRO). In dit rapport geven we antwoord op de hoofdvraag: welke interventies, processen en structuren faciliteren 'urban commoning', om te komen tot een meer gebalanceerde ontwikkeling van stedelijke consumptieruimten? Urban commoning is een gedeelde praktijk waarbij belanghebbende rondom een gemeenschappelijke bron samen regels en afspraken ontwikkelen om zo'n plek duurzaam te benutten

    Environmental risk factors of type 2 diabetes-an exposome approach

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    Type 2 diabetes is one of the major chronic diseases accounting for a substantial proportion of disease burden in Western countries. The majority of the burden of type 2 diabetes is attributed to environmental risks and modifiable risk factors such as lifestyle. The environment we live in, and changes to it, can thus contribute substantially to the prevention of type 2 diabetes at a population level. The ‘exposome’ represents the (measurable) totality of environmental, i.e. nongenetic, drivers of health and disease. The external exposome comprises aspects of the built environment, the social environment, the physico-chemical environment and the lifestyle/food environment. The internal exposome comprises measurements at the epigenetic, transcript, proteome, microbiome or metabolome level to study either the exposures directly, the imprints these exposures leave in the biological system, the potential of the body to combat environmental insults and/or the biology itself. In this review, we describe the evidence for environmental risk factors of type 2 diabetes, focusing on both the general external exposome and imprints of this on the internal exposome. Studies provided established associations of air pollution, residential noise and area-level socioeconomic deprivation with an increased risk of type 2 diabetes, while neighbourhood walkability and green space are consistently associated with a reduced risk of type 2 diabetes. There is little or inconsistent evidence on the contribution of the food environment, other aspects of the social environment and outdoor temperature. These environmental factors are thought to affect type 2 diabetes risk mainly through mechanisms incorporating lifestyle factors such as physical activity or diet, the microbiome, inflammation or chronic stress. To further assess causality of these associations, future studies should focus on investigating the longitudinal effects of our environment (and changes to it) in relation to type 2 diabetes risk and whether these associations are explained by these proposed mechanisms. Graphical abstract: [Figure not available: see fulltext.
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