4,748 research outputs found
The Challenge of Urban Regeneration in Deprived European Neighbourhoods - a Partnership Approach
This paper sets out to critically examine the adoption of a partnership approach to urban regeneration at neighbourhood level across eight European cities. While all of the cities were committed to the idea of the socially integrated city, significant differences emerged in the conceptualisation and practice of partnership at neighbourhood level. This paper draws on case studies assembled in the course of an EU funded thematic network (ENTRUST) to illustrate, in particular, the challenges associated with (1) mobilising the private sector and (2) engaging the local population in the process. The paper concludes that the experience of partnership at neighbourhood level is largely determined by contextual factors such as local and national institutional structures, political culture and the relative power of potentially competing actors within the urban regeneration system.
High School Choice in New York City: A Report on the School Choices and Placements of Low-Achieving Students
School choice policies, a fixture of efforts to improve public education in many cities. aim to enable families to choose a school that they believe will best meet their child's needs. In New York City, choice and the development of a diverse portfolio of options have played central roles in the Department of Education's high school reform efforts. This report examines the choices and placements of New York City's lowest-achieving students: those scoring among the bottom 20 percent on standardized state tests in middle school. Focusing on data from 2007 to 2011, the report looks at who these low-achieving students are, including how their demographics compare to other students in NYC, the educational challenges they face, and where they live. The bulk of the report reviews low-achieving students' most preferred schools and the ones to which they were ultimately assigned, assessing how these schools compare to those of their higher-achieving peers. The findings show that low-achieving students attended schools that were lower performing, on average, than those of all other students. This was driven by differences in students' initial choices: low-achieving students' first-choice schools were less selective, lower-performing, and more disadvantaged. Overall, lower-achievingand higher-achieving students were matched to their top choices at the same rate. Importantly, both low- and higher-achieving students appear to prefer schools that are close to home, suggesting that differences in students' choices likely reflect, at least in part, the fact that lower-achieving students are highly concentrated in poor neighborhoods, where options may be more limited
Depth from Monocular Images using a Semi-Parallel Deep Neural Network (SPDNN) Hybrid Architecture
Deep neural networks are applied to a wide range of problems in recent years.
In this work, Convolutional Neural Network (CNN) is applied to the problem of
determining the depth from a single camera image (monocular depth). Eight
different networks are designed to perform depth estimation, each of them
suitable for a feature level. Networks with different pooling sizes determine
different feature levels. After designing a set of networks, these models may
be combined into a single network topology using graph optimization techniques.
This "Semi Parallel Deep Neural Network (SPDNN)" eliminates duplicated common
network layers, and can be further optimized by retraining to achieve an
improved model compared to the individual topologies. In this study, four SPDNN
models are trained and have been evaluated at 2 stages on the KITTI dataset.
The ground truth images in the first part of the experiment are provided by the
benchmark, and for the second part, the ground truth images are the depth map
results from applying a state-of-the-art stereo matching method. The results of
this evaluation demonstrate that using post-processing techniques to refine the
target of the network increases the accuracy of depth estimation on individual
mono images. The second evaluation shows that using segmentation data alongside
the original data as the input can improve the depth estimation results to a
point where performance is comparable with stereo depth estimation. The
computational time is also discussed in this study.Comment: 44 pages, 25 figure
Le spectacle de la Flèche : la réinvention de la rue O’Connell à Dublin
Comme bien des villes britanniques et nord-amĂ©ricaines, Dublin a souffert d’une piètre planification urbanistique dans les annĂ©es 1960 et 1970. La majeure partie de la structure du centre-ville passa au bulldozer afin de crĂ©er un semblant de ville entrepreneuriale. La rĂ©imagination de la ville proposĂ©e par le conseil de ville de Dublin est Ă©tudiĂ©e ici Ă travers la reconstitution et la reprĂ©sentation rĂ©cente de la rue O’Connell, et plus particulièrement par l’insertion d’un monument spectaculaire comme pièce de rĂ©sistance du spectacle et de l’expĂ©rience qu’offre cette rue. L’auteur argumente que la municipalitĂ© poursuit trois stratĂ©gies – ayant trait au renouvellement commercial, civique et artistique de l’espace – qui se chevauchent et qui sont parfois antagonistes dans son projet de redĂ©finir symboliquement cet espace public. Ces stratĂ©gies fonctionnent parfois Ă l’unisson, mais elles entrent frĂ©quemment en conflit les unes avec les autres. Dans ce contexte, la Flèche constitue le point central d’une stratĂ©gie oĂą culture et Ă©conomie sont reliĂ©es, et qui vise Ă la fois Ă renverser les stĂ©rĂ©otypes des places urbaines ainsi qu’à inciter les Dublinois Ă considĂ©rer diffĂ©remment l’organisation spatiale de la ville.Like many other British and North American cities, Dublin suffered from poor urban planning in the 1960s and 70s. Most of the down-town area was bulldozed in order to create a sort of business city. The replanning of the city proposed by the Dublin City Council is studied here through the recent rebuilding and reinventing of O’Connell Street, and more particularly by the addition of a spectacular monument as the pièce de rĂ©sistance of the spectacle and experience that street has to offer. The author argues that the municipality is pursuing three strategies in its project of redefining this public space symbolically, These strategies relating to the commercial, civic and artistic renewal of the space sometimes harmonize but often conflict with one another. In this context, the Spire constitutes the central point of a strategy in which culture and the economy are interrelated, and which aims at both reversing the stereotypes of urban spaces (squares ?) as well as encouraging Dubliners to consider the spatial organization of their city in a different way.Como muchas ciudades británicas y nord-americanas, DublĂn sufriĂł una pobre planificaciĂłn urbanĂstica en los años 1960 y 1970. La mayor parte de la estructura del centro de la ciudad fue remodelada con el fin de crear una apariencia de ciudad empresarial. La re-imaginaciĂłn de la ciudad propuesta por el Concejo de la ciudad de DublĂn se estudia aquĂ a travĂ©s de la reconstituciĂłn y la reciente representaciĂłn de la calle O’Connell, y más concretamente por el levantamiento de un monumento espectacular como parte de resistencia del espectáculo y de la experiencia que ofrece esta calle. El autor argumenta que el municipio pretende tres estrategias – habiendo hecho la renovaciĂłn comercial, cĂvica y artĂstica del espacio – estrategias que se superponen y que son a veces antagĂłnicas en su proyecto de redefinir simbĂłlicamente este espacio pĂşblico. Estas estrategias funcionan a veces al unĂsono, pero entran frecuentemente en conflicto las unas con las otras. En este contexto, la Flecha constituye el punto central de una estrategia donde la cultura y la economĂa están interrelacionadas, y apuntan a la vez a invertir los estereotipos de los lugares urbanos asĂ como a incitar a los dublineses a considerar diferentemente la organizaciĂłn espacial de la ciudad
3-D SPH simulations of colliding winds in eta Carinae
We study colliding winds in the superluminous binary eta Carinae by
performing three-dimensional, Smoothed Particle Hydrodynamics (SPH)
simulations. For simplicity, we assume both winds to be isothermal. We also
assume that wind particles coast without any net external forces. We find that
the lower density, faster wind from the secondary carves out a spiral cavity in
the higher density, slower wind from the primary. Because of the
phase-dependent orbital motion, the cavity is very thin on the periastron side,
whereas it occupies a large volume on the apastron side. The model X-ray light
curve using the simulated density structure fits very well with the observed
light curve for a viewing angle of i=54 degrees and phi=36 degrees, where i is
the inclination angle and phi is the azimuth from apastron.Comment: 6 pages, 3 figures, To be published in Proceedings of IAU Symposium
250: Massive Stars as Cosmic Engines, held in Kauai, Hawaii, USA, Dec 2007,
edited by F. Bresolin, P.A. Crowther & J. Puls (Cambridge University Press
The promoter of the human interleukin-2 gene contains two octamer-binding sites and is partially activated by the expression of Oct-2
The gene encoding interleukin-2 (IL-2) contains a sequence 52 to 326 nucleotides upstream of its transcriptional initiation site that promotes transcription in T cells that have been activated by costimulation with tetradecanoyl phorbol myristyl acetate (TPA) and phytohemagglutinin (PHA). We found that the ubiquitous transcription factor, Oct-1, bound to two previously identified motifs within the human IL-2 enhancer, centered at nucleotides -74 and -251. Each site in the IL-2 enhancer that bound Oct-1 in vitro was also required to achieve a maximal transcriptional response to TPA plus PHA in vivo. Point mutations within either the proximal or distal octamer sequences reduced the response of the enhancer to activation by 54 and 34%, respectively. Because the murine T-cell line EL4 constitutively expresses Oct-2 and requires only TPA to induce transcription of the IL-2 gene, the effect of Oct-2 expression on activation of the IL-2 promoter in Jurkat T cells was determined. Expression of Oct-2 potentiated transcription 13-fold in response to TPA plus PHA and permitted the enhancer to respond to the single stimulus of TPA. Therefore, both the signal requirements and the magnitude of the transcription response of the IL-2 promoter can be modulated by Oct-2
Comparing the Effects of Mental Workload Between Visual and Auditory Secondary Tasks During Laparoscopy
The purpose of this study was to test Wickens’ Multiple Resource Theory (MRT) by comparing performance and subjective workload on a visual-spatial secondary task with an auditory-spatial analog when paired with visual-spatial laparoscopic primary tasks. Two primary tasks were performed with a laparoscopic box trainer: a high workload task that consisted of transferring rings from one peg to another and a low workload task that consisted of grasping and placing large pencil erasers in a bowl. It was predicted that the visual-spatial secondary task would be more sensitive when paired with the laparoscopic primary task than the auditory analog. Findings from the study mostly supported this prediction. Proportion of correct detections and subjective workload scores indicated that the auditory-spatial task secondary task was less demanding than the visual-spatial task in high workload, dual task conditions. However, no significant differences were found for response time and false alarms. Overall, these results support the modality predictions of MRT under high workload conditions. Additionally, this study provides further evidence supporting the use of the visual-spatial, ball-and-tunnel task as a measure of workload during laparoscopic surgery
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