2,026 research outputs found
Demographic dynamics, economic expansion and settlement dispersion in Southern Europe. Contrasting patterns of growth and change in three metropolitan region
Settlement densification and scattering are two processes through which cities evolved. Becoming a multidisciplinary
research issue, urban sprawl is among the major concerns in developed and emerging countries for its negative impacts on
socio-environmental complex systems. Sprawl varies at the regional scale, following different characteristics, dynamics,
effects and consequences. Consequently, converging on a unique definition for sprawl is made even more difficult when
patterns and processes of urbanization in various countries and regions are considered together. Our study aims at deriving
a comprehensive interpretation of urban scattering based on a narrative analysis of recent expansion paths in three
metropolitan cities of southern Europe (Barcelona, Istanbul, Naples) in terms of density traits, spatial forms, socioeconomic
and environmental impacts. Compared to past urban trajectories, recent processes of urban expansion produced inherent
changes in the density gradient, requiring specific actions of urban containment
Housing and the city. A spatial analysis of residential building activity and the socio-demographic background in a Mediterranean City, 1990-2017
Fluctuations in residential building activity are becoming progressively more intense over time and space in advanced economies and especially in Europe, fueling real estate market segmentation and making the performance of the construction industry increasingly unpredictable. If non-linear urbanization paths are the result of economic downturns consolidating progressively more volatile real estate markets, the present study investigates the impact of recent building cycles on long-term urban expansion in a Mediterranean city (Athens, Greece), using multiple clustering techniques run on a large set of building activity and socio-demographic indicators. Changes over time in building activity were evaluated considering 12 spatially-explicit indicators derived from the analysis of building permits released by Greek municipalities between 1990 and 2017. By referring to different analysis' scales (macro-scale: settlements, meso-scale: buildings, micro-scale: dwellings), indicators allow a comprehensive investigation of multiple dimensions and characteristics of construction markets at four-time intervals of 7 years each (1990-1996, 1997-2003, 2004-2010, 2011-2017). Spatio-temporal variability in building activity was further investigated considering 12 contextual indicators assessing the basic socio-demographic attributes of local municipalities. Cluster analysis allows identification of distinctive, local-scale responses of real estate markets to economic cycles (expansion-stagnation-recession) in both short- and long-term horizons and relate them to the dominant socio-demographic context. Density of new buildings, average floors per new building, density of buildings' additions and number of building permits per inhabitant were found to be the most sensitive indicators to economic downturns in the study area. Infrastructure-driven development, as a result of the 2004 Olympic Games, has produced relevant short-term alterations in residential construction markets, complicating urbanization trends at the local scale. Multi-scale indicators from building permit records provide a useful insight in the diachronic mechanisms of urban growth, with implications for regional planning and design of sustainable development practices
Population dynamics, agglomeration economies and municipal size. A long-term analysis
Under the hypothesis that modifications in municipal boundaries and creation (or suppression) of new administrative units reflect a progressive adjustment toward a more balanced distribution of population over space, the present study investigates the long-term relationship (1928-2012) between urban expansion, population dynamics and municipal area in a growing metropolitan region (Athens, Greece). In expanding regions, municipal size is a key variable outlining the amount and spatial concentration of services and infrastructures, resulting to be functionally related to population density, agglomeration factors, land availability to building and characteristic socioeconomic profiles of local communities. A statistical analysis of the relationship between population density and municipal area provides basic knowledge to policy and planning adjustments toward a more balanced spatial distribution of population and land among the local government units. Descriptive statistics, mapping, correlation analysis and linear regressions were used to assess the evolution of such relationship over a sufficiently long time period. The average municipal area in Athens decreased moderately over time, with a slight increase in spatial heterogeneity. Conversely, the average population density per municipality increased more rapidly, with a considerable reduction in spatial heterogeneity. The observed goodness-of-fit of the linear relationship between population density and municipal area increased significantly over time. The empirical results of our study indicate that municipal size has progressively adjusted to population density across metropolitan areas, determining a more balanced spatial distribution of the resident population, which was consolidated by the recent administrative reform of the local authorities in Greece (the so called \u2018Kallikratis\u2019 law). Such conditions represent a base for the informed analysis of the spatial structure of local administrative units and they contribute to the debate on the optimal size of municipalities and other administrative districts with relevant impact on both urban and metropolitan scales of governance
The (Evolving) vineyard\u2019s age structure in the valencian community, Spain. A new demographic approach for rural development and landscape analysis
Vineyards have assumed a key role as rural landmarks in recent decades. Investigating vineyard dynamics and contexts may reveal various economic, cultural, and environmental aspects of rural landscapes, which can be linked to land-use changes and major soil degradation processes, including soil erosion. As a contribution to rural landscape studies, the purpose of this work is to investigate the spatial distribution of vineyard plots in the Valencian community, located in the eastern area of the Iberian Peninsula, focusing on the final product, the type of vineyard and how long each vineyard has been settled over time. The work provides a comprehensive analysis of a wine-growing landscape, considering strategic (spatial) assets in present and past times. Vineyards were interpreted as a distinctive landmarks that give value to local economies, basic knowledge of how long different types of wine plots have been present in the Valencian community is useful when estimating their degree of sustainability and formulating suggestions, policies, and strategies to prevent processes of landscape degradation at various spatial scales
The production and consumption of information on intangibles: An empirical investigation of preparers and users
Nonadiabatic effects in the dynamics of atoms confined in a cylindric time-orbiting-potential magnetic trap
In a time-orbiting-potential magnetic trap the neutral atoms are confined by
means of an inhomogeneous magnetic field superimposed to an uniform rotating
one. We perform an analytic study of the atomic motion by taking into account
the nonadiabatic effects arising from the spin dynamics about the local
magnetic field. Geometric-like magnetic-fields determined by the Berry's phase
appear within the quantum description. The application of a variational
procedure on the original quantum equation leads to a set of dynamical
evolution equations for the quantum average value of the position operator and
of the spin variables. Within this approximation we derive the
quantum-mechanical ground state configuration matching the classical adiabatic
solution and perform some numerical simulations.Comment: 12 pages, 4 figure
Discharge quality from municipal wastewater treatment plants and the Sludge Biotic Index for activated sludge: integrative assessment
Abstract
Wastewater treatment plants (WWTPs) are scrutinized by Environmental Authorities particularly regarding the compliance to discharge limit values fixed by national and local regulations. An integrated approach is necessary to achieve the objectives established with Directive 2000/60/EC (WFD) considering the ecological status of the receiving water body and the quality of the discharge. Specifically, documentary, technical, management and analytical controls should be developed. Moreover, integrative information on the behaviour of the activated sludge in the aeration tank can be useful for plant managers as well as for the regulating Authorities. The study presents the experience concerning WWTP regulation considering the analytic assessment of the discharge as well the monitoring of the Sludge Biotic Index (SBI) for activated sludge. Data from monitoring during the period 2008–14 on SBI values and chemical and microbiological data on the discharges of a sample of 35 WWTPs in the province of Venice (north-east Italy, Veneto region) are presented and discussed. Together with chemical and microbiological analysis, the SBI appears to be a highly useful index for the integrative assessment of plant functionality, in particular when monitoring and identifying critical situations that can determine the exceedance of discharge limit values. The SBI method, in an integrated control approach, can be used for small and medium sized WWTPs that only treat domestic wastewaters. In a case by case assessment this may even substitute part of the analytical monitoring carried out in the WWTPs' control process
Industrial sprawl and residential housing. Exploring the interplay between local development and land-use change in the Valencian Community, Spain
Urbanization in Mediterranean Europe has occurred in recent decades with expansion of residential, commercial and industrial settlements into rural landscapes outside the traditional metropolitan boundaries. Industrial expansion in peri-urban contexts was particularly intense in Southern Europe. Based on these premises, this work investigates residential and industrial settlement dynamics in the Valencian Community, Spain, between 2005 and 2015, with the aim to clarify the role of industrial expansion in total urban growth in a paradigmatic Mediterranean region. Since the early 1990s, the Valencian industrial sector developed in correspondence with already established industrial nodes, altering the surrounding rural landscape. Six variables (urban hierarchy, discontinuous settlements, pristine land under urban expansion, isolated industrial settlements, within- and out-of-plan industrial areas) were considered with the aim at exploring land-use change. Empirical results indicate a role of industrial development in pushing urban sprawl in coastal Valencia. A reflection on the distinctive evolution of residential and industrial settlements is essential for designing new planning measures for sustainable land management and containment of urban sprawl in Southern Europe. A comparative analysis of different alternatives of urban development based on quantitative assessment of land-use change provides guidelines for local development and ecological sustainability
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