17,777 research outputs found
A worldwide model for boundaries of urban settlements
The shape of urban settlements plays a fundamental role in their sustainable
planning. Properly defining the boundaries of cities is challenging and remains
an open problem in the Science of Cities. Here, we propose a worldwide model to
define urban settlements beyond their administrative boundaries through a
bottom-up approach that takes into account geographical biases intrinsically
associated with most societies around the world, and reflected in their
different regional growing dynamics. The generality of the model allows to
study the scaling laws of cities at all geographical levels: countries,
continents, and the entire world. Our definition of cities is robust and holds
to one of the most famous results in Social Sciences: Zipf's law. According to
our results, the largest cities in the world are not in line with what was
recently reported by the United Nations. For example, we find that the largest
city in the world is an agglomeration of several small settlements close to
each other, connecting three large settlements: Alexandria, Cairo, and Luxor.
Our definition of cities opens the doors to the study of the economy of cities
in a systematic way independently of arbitrary definitions that employ
administrative boundaries
Large cities are less green
We study how urban quality evolves as a result of carbon dioxide emissions as
urban agglomerations grow. We employ a bottom-up approach combining two
unprecedented microscopic data on population and carbon dioxide emissions in
the continental US. We first aggregate settlements that are close to each other
into cities using the City Clustering Algorithm (CCA) defining cities beyond
the administrative boundaries. Then, we use data on emissions at a
fine geographic scale to determine the total emissions of each city. We find a
superlinear scaling behavior, expressed by a power-law, between
emissions and city population with average allometric exponent
across all cities in the US. This result suggests that the high productivity of
large cities is done at the expense of a proportionally larger amount of
emissions compared to small cities. Furthermore, our results are substantially
different from those obtained by the standard administrative definition of
cities, i.e. Metropolitan Statistical Area (MSA). Specifically, MSAs display
isometric scaling emissions and we argue that this discrepancy is due to the
overestimation of MSA areas. The results suggest that allometric studies based
on administrative boundaries to define cities may suffer from endogeneity bias
Identities with historical regions – are they adapting to modern administrative division? The case of Ukraine
Historical regions remain the most common basis for the formation or promotion of regional identities in Europe. However, regions and regional identities are in the process of constant formation and can change significantly in line with new conditions. In this paper we focused on the changes of the spatial spread of identities with historical regions in Ukraine in comparison to the initial boundaries of those. The results show that identities with historical regions are markedly adapting to modern administrative boundaries. At the same time, the symbolic value of historical regions constitutes an essential element of identity building in contemporary administrative regions
Gathering experience in trust-based interactions
As advances in mobile and embedded technologies coupled with progress in adhoc networking fuel the shift towards ubiquitous computing systems it is becoming increasingly clear that security is a major concern. While this is true of all computing paradigms, the characteristics of ubiquitous systems amplify this concern by promoting spontaneous interaction between diverse heterogeneous entities across administrative boundaries [5]. Entities cannot therefore rely on a specific control authority and will have no global view of the state of the system. To facilitate collaboration with unfamiliar counterparts therefore requires that an entity takes a proactive approach to self-protection. We conjecture that trust management is the best way to provide support for such self-protection measures
Ardagh Community Trust: transgressing boundaries, asserting community
Administrative boundaries are ubiquitous. A vital technology of power within the modern nation-state’s mode of bureaucratic governance, they carve up and abstract land and water alike into conceptual totalities that, in their simplification, render them legible to centralised administrative bodies. This is a foundational tool of state planning, the impact of which permeates all aspects of socio-economic life. These boundaries are not passive; they do not simply define a geographical area. Rather, they are selective in what they encompass and, as a result, what they include and exclude and what is rendered visible and, hence, valuable. This article describes an example of the real-world impact of this selectivity through discussion of the experiences of a community-led charity (Ardagh Community Trust) and the community group that founded it (Friends of Horfield Common). In their work to demonstrate that an administrative-boundary-spanning public green space (Horfield Common) and leisure facility (the Ardagh) was a vital community resource and hub, this article focuses on the work of Friends of Horfield Common/Ardagh Community Trust to ensure that their local community, one dissected by multiple administrative boundaries, was recognised and acknowledged when, in 2008, Bristol City Council in the UK proposed the sale of multiple publicly owned green spaces through their Parks and Green Space Strategy. Administrative boundaries played a key role in defining and determining which sites in the city were proposed for sale and in structuring the accompanying public consultation process, thereby determining which communities were recognised as communities in relation to this policy and, hence, which communities’ opinions were actively sought and heard. This article concludes by highlighting some of the potential political and economic costs attendant on reifying administrative boundaries rather than lived communities in both planning and consultation processes
Hierarchical Spatial Reasoning Applied to Automated Design of Administrative Boundaries
Throughout history, humankind has segmented and delineated the geospatial environment in various ways to support administrative, political and economic activities. To date, the majority of spatial boundaries have been constructed in an uncoordinated manner
with individual organisations generating individual boundaries to meet individual needs. This practice has resulted in boundary layers that even the most sophisticated GIS (Geographic Information System) technology is unable to cross analyse accurately. Consequently,
geospatial information is fragmented over a series of boundary units.
The objective of this paper is to investigate new methods for the
organisation of spatial data by applying the principles of Hierarchical Spatial Reasoning (HSR), where HSR can be used as the theoretical framework for investigating the hierarchical structuring of space and
for providing new methods for accurate data exchange. Also, to present the issues found in the development of a prototype developed
for delineating boundaries within the GIS environment. This prototype has been constructed utilising the state of Victoria, Australia as a working laboratory for development and analysis
Figure 6.2 Administrative boundaries, urbanization, and policy areas in Vancouver.pdf
Note: Since 1995 the Lower Mainland has been divided into two regional districts. The Agricultural Land Reserve (ALR), established in 1973, prohibits urban development in much of the region. Urban development has been largely contiguous and compact, forming discrete settlements in the ALR’s “holes.”https://ir.lib.uwo.ca/shapingthemetropolis/1017/thumbnail.jp
Hierarchical Spatial Reasoning Applied to Automated Design of Administrative Boundaries
Throughout history, humankind has segmented and delineated the geospatial environment in various ways to support administrative, political and economic activities. To date, the majority of spatial boundaries have been constructed in an uncoordinated manner
with individual organisations generating individual boundaries to meet individual needs. This practice has resulted in boundary layers that even the most sophisticated GIS (Geographic Information System) technology is unable to cross analyse accurately. Consequently,
geospatial information is fragmented over a series of boundary units.
The objective of this paper is to investigate new methods for the
organisation of spatial data by applying the principles of Hierarchical Spatial Reasoning (HSR), where HSR can be used as the theoretical framework for investigating the hierarchical structuring of space and
for providing new methods for accurate data exchange. Also, to present the issues found in the development of a prototype developed
for delineating boundaries within the GIS environment. This prototype has been constructed utilising the state of Victoria, Australia as a working laboratory for development and analysis
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