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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
581

Feeling the Pull of Gravity: Reconnecting Recreation, Nature, and Community through Public Outdoor Recreation Facilities in Revelstoke, British Columbia

Goodlad, Keri Lynn 10 July 2012 (has links)
This thesis suggests that architectural interventions can aid in reintegrating an ethos of interconnectedness between recreationists and nature, as well as between recreationists and community, by emphasizing and intertwining natural forces and cultural flows. The analogy of a skier in motion, interacting with the landscape and gravity, inspires architectural moves. Revelstoke, British Columbia, Canada, a prime example of a mountain community that has experienced a shift to corporate-based skiing, is the location for this exploration.
582

Vacuum polarization and Hawking radiation

Rahmati, Shohreh January 2012 (has links)
Quantum gravity is one of the interesting fields in contemporary physics which is still in progress. The purpose of quantum gravity is to present a quantum description for spacetime at 10 33cm or find the `quanta' of gravitational interaction.. At present, the most viable theory to describe gravitational interaction is general relativity which is a classical theory. Semi-classical quantum gravity or quantum field theory in curved spacetime is an approximation to a full quantum theory of gravity. This approximation considers gravity as a classical field and matter fields are quantized. One interesting phenomena in semi-classical quantum gravity is Hawking radiation. Hawking radiation was derived by Stephen Hawking as a thermal emission of particles from the black hole horizon. In this thesis we obtain the spectrum of Hawking radiation using a new method. Vacuum is defined as the possible lowest energy state which is filled with pairs of virtual particle-antiparticle. Vacuum polarization is a consequence of pair creation in the presence of an external field such as an electromagnetic or gravitational field. Vacuum polarization in the vicinity of a black hole horizon can be interpreted as the cause of the emission from black holes known as Hawking radiation. In this thesis we try to obtain the Hawking spectrum using this approach. We re-examine vacuum polarization of a scalar field in a quasi-local volume that includes the horizon. We study the interaction of a scalar field with the background gravitational field of the black hole in the desired quasi-local region. The quasi-local volume is a hollow cylinder enclosed by two membranes, one inside the horizon and one outside the horizon. The net rate of particle emission can be obtained as the difference of the vacuum polarization from the outer boundary and inner boundary of the cylinder. Thus we found a new method to derive Hawking emission which is unitary and well defined in quantum field theory. / ix, 109 leaves : ill. ; 29 cm
583

Joint inversion of travel-time residuals and gravity anomalies for the velocity structure of Southest Tennessee

Kaufmann, Ronald Douglas 05 1900 (has links)
No description available.
584

Axisymmetric internal solitary waves launched by river plumes

McMillan, Justine M. Unknown Date
No description available.
585

Gravity currents in two-layer stratified media

Tan, Alan Unknown Date
No description available.
586

Propagation and breaking of nonlinear internal gravity waves

Dosser, Hayley V Unknown Date
No description available.
587

Gravity waves in a primitive-equations model of the atmosphere.

Crowe, Brian Woodhull January 1969 (has links)
No description available.
588

Saturation d'ondes de gravité et balance non-linéaire

Ménard, Richard. January 1985 (has links)
No description available.
589

Chemically enhanced gravitational solid-liquid separation for the management of phosphorus in liquid swine manure

Agomoh, Ikechukwu Vincent 11 September 2012 (has links)
This laboratory column (125 cm high, 15 cm diameter) research investigated solids and P removal from liquid swine manure amended with calcium carbonate, magnesium sulphate, alum and polyacrylamide (PAM). Results showed that PAM was the most effective amendment for enhancing solids removal from manure containing 1% initial total solids (TS). The effectiveness of PAM was lower at 5% and 8% than at 1% due to resuspension of solids occurring at settling times beyond 4 h. After 24 h of settling, P removal from non-amended manure was comparable to that in amended manure and decreased with TS concentration for all amendments except alum, which was equally effective at all TS concentrations. These results indicate that, for manure containing 1% TS, P can be adequately removed by gravity separation without addition of chemical amendments while alum is a more effective amendment for removing P from manure containing higher (5% and 8%) TS.
590

Spatial dynamics of the population in the Czech Republic (1989 - 2007)

Vobecka, Jana 30 August 2010 (has links) (PDF)
The aim of the thesis is to describe, analyse and discuss the development of spatial population dynamics in the Czech Republic between 1989 and 2007. Demographic structure and migration, the two components of spatial population dynamics, are analysed using two spatial dimensions, the urban-suburban-rural gradient and the core-periphery region distinction, using quantitative analyses, including gravity regression modelling of migration. The analysis primarily focuses on domestic migration as the main vehicle of spatial population dynamics. It discusses the structure, determinants, and temporal evolution of migration and its consequences on the population structure in different spatial categories. The thesis indicates that suburbanisation has recently become the main factor influencing Czech spatial population dynamics. The key factor determining migration destination is the social status of migrants, whereas age has only secondary importance. However, since Czechs are not very mobile, population dispersal is less large-scale than in Western-Europe. This explains why recent domestic migration patterns have had only a small measurable influence on the social or demographic structures of the population across spatial categories.

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