4,051 research outputs found
Urban Walkability Measures: Data Quality, Cautions, and Associations with Active and Public Transportation Across Canada
Geographical Information Systems (GIS) has emerged as a primary tool to study the built environment (BE) and its correlates. Accurate results employing GIS-based methods, however, depend on high-quality data sets and agreement on the appropriate nature and scale of areal units. Exploratory groundtruthing exercises illuminated possible issues of data accuracy. GIS-derived walkability measures for intersection density and land use mix were calculated for 2011 using Census of Canada data to determine whether commercially- or municipally-sourced urban data sets were better suited for BE studies. Road network data were ‘cleaned’ to remove unwalkable sections of road and to repair instances of intersection overrepresentation. Results suggested that municipal land use data and commercial road network data were ideal and both sources of data have benefits and limitations that should be discussed prior to any large research analysis. The second major analysis in this thesis utilized DMTI road and land use data and journey-to-work transportation data for three Canadian census years – 2001, 2006, 2011 – for thirty-three Canadian Census Metropolitan Areas (CMAs) to determine if a Canada-wide association between walkability and active and public transportation (AT/PT) exists. Using a Spearman’s Rank correlation matrix, walkability was positively associated with AT, PT, and AT/PT (r = 0.324 – 0.459; p \u3c 0.01) and negatively associated with median household income and age of development (r = 0.124 – 0.222; p \u3c 0.01) for all three census years. Study findings can be used to inform urban transportation and public planning policies dependent on multi-modal transit networks
Notes on the 1977 summer study program in geophysical fluid dynamics at the Woods Hole Oceanographic Institution
The lectures by Marten Landahl, recorded in the first part of
this report, served as the introduction to the study of turbulence which
was the principal theme of the nineteenth summer program in Geophysical
Fluid Dynamics at the Woods Hole Oceanographic Institution.Office of Naval Research
under Contract NGG014-77-C-046
Notes on the 1971 summer study program in geophysical fluid dynamics at the Woods Hole Oceanographic Institution
A topic, such as planetary atmospheric dynamics, is necessarily
a speculative one because of the extreme difficulty of obtaining detailed observations.
A single datum is often responsible for several
"theories". Andy Ingersoll was continually challenged during his attempts
to present a coherent picture of a broad spectrum of observations
and speculations about the atmospheres of the planets. He emerged somewhat
battered but still intact. All of us felt rewarded by his efforts.
The formal lectures were followed by a microsymposium on planetary
atmospheres which included discussions of the latest observations, speculative
theories and simple models of certain gross features.National Science Foundatio
Notes on the 1972 Summer Study Program in Geophysical Fluid Dynamics at the Woods Hole Oceanographic Institution
The effect of gravity on fluids of varying density is of fundamental
importance in natural flows. This subject formed the topic of
concentration for the fourteenth summer program in Geophysical Fluid
Dynamics at the Woods Hole Oceanographic Institution. We had the good
fortune to hear Stewart Turner lecture on stratified flows just after
he had completed the manuscript for his book on the subject. Turner
chose to emphasize nonlinear and turbulent aspects of stratified flows
and, therefore, had to give up the deductive approach in favor of
treatments based on dimensional analysis and similarity arguments.
This summary of the many experimental studies of these flows increased
our awareness of the fascinating variety of phenomena in which stratification
plays so vital a role.Supported by the Division of Fluid
Dynamics, Oceanography and Applied Mathematics of the Office of Naval
Research
Notes on the 1974 summer study program in geophysical fluid dynamics at the Woods Hole Oceanographic Institution
This year the central topic was the general circulation of the oceans.
Some of the basic ideas used in wind-driven and thermohaline studies were
presented in the introductory course of lectures and simple models that have
guided our thinking in the development of the topic were discussed. As part
of the introductory lectures Peter Niiler developed a model of the mixed layer,
exploring the reasoning and the parameterization behind the theories of this
important boundary region at the surface of the ocean. Dennis Moore gave a
careful account of transient flows in equatorial regions and showed how dynamical
conditions on the eastern and western boundaries are satisfied by a
superposition of planetary, Kelvin and Yanai waves. Peter Rhines concluded
the series with a discussion of topographically induced low frequency motions.
At the request of the students Joseph B. Keller gave a lecture on "Solution
of Partial Differential Equations by Ray Theory".National Science Foundatio
Notes on the 1968 Summer Study Program in Geophysical Fluid Dynamics at the Woods Hole Oceanographic Institution
Originally issued as Reference No. 68-72, series later renamed WHOI-.The general circulation of the oceans was the topic of concentration
for the 1968 WHOI Summer Program in Geophysical Fluid DynamicsNational Science Foundatio
Notes on the 1976 Summer Study Program in Geophysical Fluid Dynamics at the Woods Hole Oceanographic Institution
Originally issued as Reference no. 76-81Global climatology was the principal theme of the eighteenth summer program in Geophysical Fluid Dynamics at the Woods Hole Oceanographic Institution.
This single volume contains course lectures, abstracts of seminars and lectures
by summer fellows.
As in previous years, the summer fellows were responsible for preparing a
first draft of the course lectures on the principal theme. In most cases, the
lecturer has been able to re-work the material further. The course lecturers,
all of whom contributed so much to the program, are Richard S. Lindzen, Wallace
S. Broecker, Abraham H. Oort, John Imbrie, Thomas Vonder Haar, Gerald R. North,
Claes Rooth, Gene E. Birchfield, and Richard C. Somerville.
The abstracted seminars cover a broad range of topics, including a one week
symposium on planetary and benthic boundary layers. Much valuable material
is referred to in these abstracts.
The major creative products of the summer are the lectures of the ten
fellows. These lectures have not been edited or reviewed in the manner appropriate
for published papers, and should be regarded as unpublished manuscripts.
Readers who would like to quote or use the material should write directly to the
authors .
As in previous years, much of the ultimate value of this summer's activities
is likely to appear as published papers during the next year or two. In
this sense, the material in this volume is simply a report of an ongoing research
effort.
We all express our thanks to the National Science Foundation, which provided
the bulk of the financial support, the Office of Naval Research, which
supported the Boundary Layer Symposium and some of the staff participation, and
to Mary C. Thayer, who managed the program and prepared this volume
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