1,866,563 research outputs found
Walk to transit or drive to transit?
No full textThe most common form of access to urban transit is by foot. Early suburban and exurban commuting to urban centers was facilitated first by commuter rail along existing intercity rail lines and then by interurban services that were often electrified. Since these services generally connected town centers most access to them was by foot and occasionally by horse. The rise of automobility in the early decades of the twentieth century facilitated by increased roadbuilding and paving, led to greater automobile commuting or driving to stations. The provision of park and ride facilities was greatly influenced by shifts in U.S. transportation policy and funding, beginning in the 1960s. The park and ride idea has been imported by many transit systems around the world, although most have made significant departures from the American model in both form and provision. Walk-to and drive-to transit are compared and the consequences of investment in park and ride and “kiss and ride,” especially in the U.S. and Canadian contexts, are explored. It is found that drive-to transit comes with considerable environmental, fiscal and opportunity costs and that its funding could be applied more productively to improving local transit and pedestrians conditions
Random walk with barycentric self-interaction
Get PDFWe study the asymptotic behaviour of a -dimensional self-interacting random walk () which is repelled or attracted by the centre of mass of its previous trajectory. The walk's trajectory models a random polymer chain in either poor or good solvent. In addition to some natural regularity conditions, we assume that the walk has one-step mean drift directed either towards or away from its current centre of mass and of magnitude for . When and the radial drift is outwards, we show that is transient with a limiting (random) direction and satisfies a super-diffusive law of large numbers: converges almost surely to some random vector. When there is sub-ballistic rate of escape. For we give almost-sure bounds on the norms , which in the context of the polymer model reveal extended and collapsed phases. Analysis of the random walk, and in particular of , leads to the study of real-valued time-inhomogeneous non-Markov processes on with mean drifts at given approximately by , where and . The study of such processes is a time-dependent variation on a classical problem of Lamperti; moreover, they arise naturally in the context of the distance of simple random walk on from its centre of mass, for which we also give an apparently new result. We give a recurrence classification and asymptotic theory for processes just described, which enables us to deduce the complete recurrence classification (for any ) of for our self-interacting walk
Replication Data for: Social Media Narratives across Platforms in Conflict: Evidence from Syria
No full textReplication data for Social Media Narratives across Platforms in Conflict: Evidence from Syria authors Erin Walk, Elizabeth Parker-Magyar, Ahmet Akbiyik, Kiran Garimella and Fotini Christi
Random walk on the range of random walk
Get PDFWe study the random walk X on the range of a simple random walk on ℤ d in dimensions d≥4. When d≥5 we establish quenched and annealed scaling limits for the process X, which show that the intersections of the original simple random walk path are essentially unimportant. For d=4 our results are less precise, but we are able to show that any scaling limit for X will require logarithmic corrections to the polynomial scaling factors seen in higher dimensions. Furthermore, we demonstrate that when d=4 similar logarithmic corrections are necessary in describing the asymptotic behavior of the return probability of X to the origin
Walk in centres: lessons from Canada
No full textThe current reforms of the United Kingdom's primary healthcare sector intend to improve accessibility to health care. One of the proposals is to introduce "walk-in" primary care centres. The intention is to pilot "a series of nurse led centres which can be used on a `drop in' basis, providing minor treatment, health information and self help advice."
The Canadian medical system has many similarities to the British system. Canada's health system is funded through general taxation (and Medicare premiums), and its general practitioners (family physicians) have a gatekeeper role to secondary care in most provinces. Canada has had walk-in centres for over 20 years. However, these centres are a doctor led service. The lessons learnt in Canada about walk-in centres may be relevant to the NHS. In this article I review the available literature about Canadian walk-in centres
Swinburne Walk, 1971
No full textLooking east along Swinburne Walk prior to shrub plantings beside rail embankment circa in June 1971
Logarithmic speeds for one-dimensional perturbed random walk in random environment
Get PDFWe study the random walk in random environment on Z+ = f0; 1; 2; : : :g, where the environment is subject to a vanishing (random) perturbation. The two particular cases that we consider are: (i) random walk in random environment perturbed from Sinai's regime; (ii) simple random walk with random perturbation. We give almost sure results on how far the random walker is from the origin, for almost every environment. We give both upper and lower almost sure bounds. These bounds are of order (log t), for 2 (1;1), depending on the perturbation. In addition, in the ergodic cases, we give results on the rate of decay of the stationary distribution
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