42,328 research outputs found
The Implications of Densification Policies for Greater Resistencia (Argentina): an Assessment of Recent Experience
. Since 2001, Resistencia City Council has been promoting growth in building height by steering development towards built-up areas in central districts that already have complete infrastructure, through the implementation of the Ordinance 5403/01 - high density. If Ordinance 5403/01 is to be accomplished, with the proposed density of up to 2400 inhabitants, there is a need for 128 hectares of green open space at the neighborhood level (Pérez and Schneider, 2011). In the last 10 years, although the population growth of the city (16%) has been followed by an increase in the supply of greenfield per inhabitant (85%), this increase has not been reflected in the inner city areas, where there is a higher population density. This legislation does, however, include sections that make it possible to optimize this situation. This paper continues on from previous studies and attempts an analysis of the application of existing legislation that proposed the intensification of land use in built up core of Resistencia city. It is focused on an assessment of the scope of the implementation of this legislation, with an emphasis on the design of buildings which enable the supply of areas dedicated to leisure or recreation, which would allow a decompression in the demand for green spaces in the central area
On the parsing of context-free languages by pushdown automata
Straightforward algorithm for converting context free grammars into pushdown-store automat
Growth of Sr1-xCaxRuO3 thin films by metalorganic aerosol deposition
We report the growth of thin films of Sr1-xCaxRuO3 on SrTiO3 and MgO
substrates by metalorganic aerosol deposition. The structure and microstructure
is characterized by X-ray diffraction and room-temperature scanning tunnelling
microscopy (STM), respectively. STM indicates in-plane epitaxy and a small
surface roughness for films on SrTiO3. The high-quality of the films is
supported by large residual resistivity ratios up to 29.Comment: 4 Pages, 2 Figures, submitted to Proceedings of ICM 2009 (Karlsruhe
Greater Resistencia Study Case: Greenfield and Increased Densification
. This paper focuses on one of the relevant issues of the phenomena of urban expansion and densification, i.e. the lack of planning of public greenfields. At the regional level, since 2001, Resistencia City Council has been promoting a growth in height by increasing built-up areas in central districts that have complete infrastructure, through the implementation of the Ordinance 5403/01 - high density. On the other hand, in the last 10 years the population growth of the city (16%) has been followed by an increase in the supply of open space per inhabitant (85%). However, this increase is not reflected in the inner city areas, where the higher population density is located. This paper aims to analyze and relate the results arising, so far, from the densification of central areas and its relationship with the availability of open space in central districts of Greater Resistencia City
On the occurrence of Berezinskii-Kosterlitz-Thouless behavior in highly anisotropic cuprate superconductors
The conflicting observations in the highly anisotropic Bi2Sr2CaCu2O8+x,
vidence for BKT behavior emerging from magnetization data and smeared 3D-xy
behavior, stemming form the temperature dependence of the magnetic in-plane
penetration depth are traced back to the rather small ratio, gsic+/gsic-=0.45,
between the c-axis correlation length probed above (+) and below (-) Tc, and
the comparatively large anisotropy. The latter leads to critical amplitudes
gsic0+,-which are substantially smaller than the distance between two CuO2
double layers. In combination with gsic+/gsic-=0.45 and in contrast to the
situation below Tc the c-axis correlation length gsic exceeds the distance
between two CuO2 double layers very close to Tc only. Below this narrow
temperature regime where 3D-xy fluctuations dominate, there is then an extended
temperature regime where the units with two CuO2 double layers are nearly
uncoupled so that 2D thermal fluctuations dominate and BKT features are
observable.Comment: 4 pages, 4 figure
3D simulations of pillars formation around HII regions: the importance of shock curvature
Radiative feedback from massive stars is a key process to understand how HII
regions may enhance or inhibit star formation in pillars and globules at the
interface with molecular clouds. We aim to contribute to model the interactions
between ionization and gas clouds to better understand the processes at work.
We study in detail the impact of modulations on the cloud-HII region interface
and density modulations inside the cloud. We run three-dimensional
hydrodynamical simulations based on Euler equations coupled with gravity using
the HERACLES code. We implement a method to solve ionization/recombination
equations and we take into account typical heating and cooling processes at
work in the interstellar medium and due to ionization/recombination physics. UV
radiation creates a dense shell compressed between an ionization front and a
shock ahead. Interface modulations produce a curved shock that collapses on
itself leading to stable growing pillar-like structures. The narrower the
initial interface modulation, the longer the resulting pillar. We interpret
pillars resulting from density modulations in terms of the ability of these
density modula- tions to curve the shock ahead the ionization front. The shock
curvature is a key process to understand the formation of structures at the
edge of HII regions. Interface and density modulations at the edge of the cloud
have a direct impact on the morphology of the dense shell during its formation.
Deeper in the cloud, structures have less influence due to the high densities
reached by the shell during its expansion.Comment: Accepted by A&A 03/11/201
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