55,446 research outputs found
Impacts of large scale development: does space make a difference?
Large scale development, a process to rapidly transform urban built environment since the
industrial modernism, has been often criticized for creating fragmented environments that impair
urban vitality. Many opponents of large scale development, especially the Jacobists, further
addressed its destructive impacts upon those most directly affected, such as the communities and
the marginal businesses in the vicinity. How far does an insertion of a large scale development
impact on its surroundings? And how far do the surroundings impact on a development? Does
space, or space configuration as defined by Hillier, matter in the two-way processes of interaction
between a development and its surroundings at the urban design level? This paper gives a
comparative study, through the appliance of space syntax methodology, of Canary Wharf in
London and Brindleyplace in Birmingham from 1991 to 2001. During this period, Canary Wharf
had slowly shifted evolving from development with deregulation in the first phase to a process of
cooperation with local authorities, whilst benefiting from good links to the rest of London via a
tube line and an express way, but it has been still criticized for failing to achieve social
regeneration; Brindleyplace, however, at first applied a traditional urban design approach to
integration with urban setting and has been appraised as a model of urban renaissance. This paper
analyses whether the different spatial strategies result in the different spatial configurations, and
then whether pedestrian movement dynamics and social aggregations respond to and shape the
different spatial configurations before and after the developments. Evidence from these aspects
direct the paper to suggest that spatial configurations at street level could play a fundamental role,
prior to and beyond development size, in two-way impacts between a large scale development and
its surroundings, whether positive or negative. Furthermore, it argues that whether a large scale
development becomes a positive or negative attractor to its surroundings at a variety of
interconnected levels could be primarily determined by the relationship between spatial patterns at
different radii. The process of two-way influences between a development and its surroundings
might shed the light on interaction between pattern and process in complex urban system and
related social issue of urban fragmentation during the period of rapid but planned urban
transformation after the Industry Revolution
Far field perturbations caused by a roughness element to the three dimensional hypersonic plate flow boundary layer
For the three dimensional hypersonic viscous compressible flat plate flow, when there is only small roughness on the wall, its effect can be considered as perturbation to two dimensional roughness-free plate flow. To study such a flow problem, we will assume there is only a single roughness element on the plate, of which the equation is in the self-similar form η = eY0 (E), where E =zx -¾ and e << 1, and thus the perturbed flow boundary layer equations will also have self-similar solutions. When solving the boundary layer equations, we use the Dorodnitsyn Transformation and write the solutions in coordinate asymptotic expansions. In these expansions, the leading order terms are the solutions to the two dimensional flat plate flow boundary layer equations, and the expression of these terms will be treated as already known since they can be obtained from the Blasius Equation.
The solutions for the perturbation terms show that the perturbations produced by the roughness are capable of propagating against the flow in the boundary layer. This is despite the fact that in the flow regime analysed in this thesis the longitudinal boundary-layer equation does not involve the pressure gradient, and this equation can be thought of as parabolic.Open Acces
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