Visual communication in urban planning and urban design

This report documents the current status of visual communication in urban design and planning. Visual communication is examined through discussion of standalone and network media, specifically concentrating on visualisation on the World Wide Web(WWW).Firstly, we examine the use of Solid and Geometric Modelling for visualising urban planning and urban design. This report documents and compares examples of the use of Virtual Reality Modelling Language (VRML) and proprietary WWW based Virtual Reality modelling software. Examples include the modelling of Bath and Glasgow using both VRML 1.0 and 2.0. A review is carried out on the use of Virtual Worldsand their role in visualising urban form within multi-user environments. The use of Virtual Worlds is developed into a case study of the possibilities and limitations of Virtual Internet Design Arenas (ViDAs), an initiative undertaken at the Centre for Advanced Spatial Analysis, University College London. The use of Virtual Worlds and their development towards ViDAs is seen as one of the most important developments in visual communication for urban planning and urban design since the development plan.Secondly, photorealistic media in the process of communicating plans is examined.The process of creating photorealistic media is documented, examples of the Virtual Streetscape and Wired Whitehall Virtual Urban Interface System are provided. The conclusion is drawn that although the use of photo-realistic media on the WWW provides a way to visually communicate planning information, its use is limited. The merging of photorealistic media and solid geometric modelling is reviewed in the creation of Augmented Reality. Augmented Reality is seen to provide an important step forward in the ability to quickly and easily visualise urban planning and urban design information.Thirdly, the role of visual communication of planning data through GIS is examined interms of desktop, three dimensional and Internet based GIS systems. The evolution to Internet GIS is seen as a critical component in the development of virtual cities which will allow urban planners and urban designers to visualise and model the complexity of the built environment in networked virtual reality.Finally a viewpoint is put forward of the Virtual City, linking Internet GIS with photorealistic multi-user Virtual Worlds. At present there are constraints on how far virtual cities can be developed, but a view is provided on how these networked virtual worlds are developing to aid visual communication in urban planning and urban design

Online participation: the Woodberry Down experiment

The internet and world wide web are generating radical changes in the way we are able tocommunicate. Our ability to engage communities and individuals in designing theirenvironment is also beginning to change as new digital media provide ways in whichindividuals and groups can interact with planners and politicians in exploring their future.This paper tells the story of how the residents of one of the most disadvantagedcommunities in Britain ? the Woodberry Down Estate in the London borough ofHackney ? have begun to use an online system which delivers everything from routineservices about their housing to ideas about options for their future. Woodberry Down isone of the biggest regeneration projects in Western Europe. It will take at least 10 years,probably much longer, to complete, at a cost of over £150 million. Online participation isone of the many ways in which this community is being engaged but as we will show, itis beginning to act as a catalyst. The kinds of networks which are evolving aroundsystems like these will change the nature of participation itself, the ways we need to thinkabout it, and the ways we need to respond. Before the experiment is described, we set thecontext by describing the wide range of digital media for communicating plans andplanning which suggests a new typology for web participation consistent with this fastemerging network culture

Modelling virtual urban environments

In this paper, we explore the way in which virtual reality (VR) systems are being broadened to encompass a wide array of virtual worlds, many of which have immediate applicability to understanding urban issues through geocomputation. Wesketch distinctions between immersive, semi-immersive and remote environments in which single and multiple users interact in a variety of ways. We show how suchenvironments might be modelled in terms of ways of navigating within, processes of decision-making which link users to one another, analytic functions that users have to make sense of the environment, and functions through which users can manipulate, change, or design their world. We illustrate these ideas using four exemplars that we have under construction: a multi-user internet GIS for Londonwith extensive links to 3-d, video, text and related media, an exploration of optimal retail location using a semi-immersive visualisation in which experts can explore such problems, a virtual urban world in which remote users as avatars can manipulate urban designs, and an approach to simulating such virtual worlds through morphological modelling based on the digital record of the entire decision-making process through which such worlds are built

First ALMA Observation of a Solar Plasmoid Ejection from an X-ray Bright Point

Eruptive phenomena such as plasmoid ejections or jets are an important feature of solar activity with the potential for improving our understanding of the dynamics of the solar atmosphere. Such ejections are often thought to be signatures of the outflows expected in regions of fast magnetic reconnection. The 304 A EUV line of Helium, formed at around 10^5 K, is found to be a reliable tracer of such phenomena, but the determination of physical parameters from such observations is not straightforward. We have observed a plasmoid ejection from an X-ray bright point simultaneously at millimeter wavelengths with ALMA, at EUV wavelengths with AIA, in soft X-rays with Hinode/XRT. This paper reports the physical parameters of the plasmoid obtained by combining the radio, EUV and X-ray data. As a result, we conclude that the plasmoid can consist either of (approximately) isothermal 10^5 K plasma that is optically thin at 100 GHz, or else a 10^4 K core with a hot envelope. The analysis demonstrates the value of the additional temperature and density constraints that ALMA provides, and future science observations with ALMA will be able to match the spatial resolution of space-borne and other high-resolution telescopes.Comment: 10 page, 5 figures, accepted for publication in Astrophysical Journal Letter. The movie can be seen at the following link: http://hinode.nao.ac.jp/user/shimojo/data_area/plasmoid/movie5.mp

Galaxy Distances in the Nearby Universe: Corrections For Peculiar Motions

By correcting the redshift--dependent distances for peculiar motions through a number of peculiar velocity field models, we recover the true distances of a wide, all-sky sample of nearby galaxies (~ 6400 galaxies with velocities cz<5500 km/s), which is complete up to the blue magnitude B=14 mag. Relying on catalogs of galaxy groups, we treat ~2700 objects as members of galaxy groups and the remaining objects as field galaxies. We model the peculiar velocity field using: i) a cluster dipole reconstruction scheme; ii) a multi--attractor model fitted to the Mark II and Mark III catalogs of galaxy peculiar velocities. According to Mark III data the Great Attractor has a smaller influence on local dynamics than previously believed, whereas the Perseus-Pisces and Shapley superclusters acquire a specific dynamical role. Remarkably, the Shapley structure, which is found to account for nearly half the peculiar motion of the Local Group, is placed by Mark III data closer to the zone of avoidance with respect to its optical position. Our multi--attractor model based on Mark III data favors a cosmological density parameter Omega ~ 0.5 (irrespective of a biasing factor of order unity). Differences among distance estimates are less pronounced in the ~ 2000 - 4000 km/s distance range than at larger or smaller distances. In the last regions these differences have a serious impact on the 3D maps of the galaxy distribution and on the local galaxy density --- on small scales.Comment: 24 pages including (9 eps figures and 7 tables). Figures 1,2,3,4 are available only upon request. Accepted by Ap

OMEGA AND BIASING FROM OPTICAL GALAXIES VERSUS POTENT MASS

The mass density field in the local universe, recovered by the POTENT method from peculiar velocities of $\sim$3000 galaxies, is compared with the density field of optically-selected galaxies. Both density fields are smoothed with a Gaussian filter of radius 12 $h^{-1}$ Mpc. Under the assumptions of gravitational instability and a linear biasing parameter b\sbo between optical galaxies and mass, we obtain \beta\sbo \equiv \om^{0.6}/b\sbo = 0.74 \pm 0.13. This result is obtained from a regression of POTENT mass density on optical density after correcting the mass density field for systematic biases in the velocity data and POTENT method. The error quoted is just the $1\sigma$ formal error estimated from the observed scatter in the density--density scatterplot; it does not include the uncertainty due to cosmic scatter in the mean density or in the biasing relation. We do not attempt a formal analysis of the goodness of fit, but the scatter about the fit is consistent with our estimates of the uncertainties.Comment: Final revised version (minor typos corrected). 13 pages, gzipped tar file containing LaTeX and figures. The Postscript file is available at ftp://dust0.dur.ac.uk/pub/mjh/potopt/potopt.ps.Z or (gzipped) at ftp://xxx.lanl.gov/astro-ph/ps/9501/9501074.ps.gz or via WWW at http://xxx.lanl.gov/ps/astro-ph/9501074 or as separate LaTeX text and encapsulated Postscript figures in a compressed tar'd file at ftp://dust0.dur.ac.uk/pub/mjh/potopt/latex/potopt.tar.

Nonaxisymmetric, multi-region relaxed magnetohydrodynamic equilibrium solutions

We describe a magnetohydrodynamic (MHD) constrained energy functional for equilibrium calculations that combines the topological constraints of ideal MHD with elements of Taylor relaxation. Extremizing states allow for partially chaotic magnetic fields and non-trivial pressure profiles supported by a discrete set of ideal interfaces with irrational rotational transforms. Numerical solutions are computed using the Stepped Pressure Equilibrium Code, SPEC, and benchmarks and convergence calculations are presented.Comment: Submitted to Plasma Physics and Controlled Fusion for publication with a cluster of papers associated with workshop: Stability and Nonlinear Dynamics of Plasmas, October 31, 2009 Atlanta, GA on occasion of 65th birthday of R.L. Dewar. V2 is revised for referee

Ceramic applications in turbine engines

The design and testing of gas turbine engines employing ceramic components is discussed. Thermal shock and vibration test results as well as spin tests of various engine components are discussed