Thesis (M. Eng.) -- Memorial University of Newfoundland, 1984. / Bibliography : leaves 28-30. Also available online.

Thesis (Ph.D.)--Memorial University of Newfoundland, 1997. / Restricted until May 1999. Bibliography: leaves 266-276.

No description available.

Ice shelves play an important role in the mass balance of an ice sheet, by providing a link between the ocean and ice. Melting at the base of an ice shelf can play a vital role in its mass balance and stability. Topographic channel features have been found on the base of ice shelves, and have been found to alter melting, however the mechanism behind this alteration is unknown. Petermann Glacier is a major outlet glacier in North West Greenland, draining approximately 6% of Greenland Ice Sheet. It terminates in a long, thin ice shelf, constrained within a high-walled fjord. The ice shelf has pronounced longitudinal channel features on its base, which limited observations suggest direct ocean currents in a mixed layer of ocean and melt waters, focusing melt in these regions. Petermann Glacier underwent two large calving events in 2010 and 2012, and the impact of these events, or possible further calving events, on basal melting is unknown. Using the MITgcm to model the ocean cavity beneath an idealised ice shelf, this thesis discusses the impact of basal channels on interactions at the ice base and circulation within the cavity. This is supplemented with a modelling investigation into the interactions beneath Petermann Glacier, and the impact of recent calving events. The inclusion of channels was found to have a stabilising effect on the ice shelf by decreasing the mean basal melt rate, caused by the refocusing, and decrease in intensity of, the meltwater layer flow beneath the ice shelf. This stabilisation and resulting 'survivor bias' explains why channels are commonly found on the base of warm water ice shelves. The model of Petermann Glacier found similar melt patterns to observational studies, however with a lesser magnitude. The calving events of 2010 and 2012 removed areas of ice shelf with low melt rates, resulting in little impact on the overall volume of ice removed through ocean melting, though further calving would vastly reduce the volume of ice melted. One consequence of calving is the increase in melting-induced undercutting at the ice front, leading to the potential for enhanced secondary calving.

Theme of this diploma thesis is the design of ice resurfacer. It deals with design of a special automatic vehicle, which is able to execute the process of ice resurfacing, without human control. With regard to the protection of the environment and health of the people inside rink arena, the propulsion system is based on the electric motor, with batteries as a power source. Final design reflects innovation of the automatization in this area. The appearance supports the uniqueness and the timelessness of the ice resurfacer and it is build up on the principles of the streamline design, with emphasis on the purity of form.

No description available.

No description available.

Typescript, etc. / Digitized by Kansas State University Libraries

Typescript, etc.

Magnetic nanostructures provide the opportunity to investigate a number ofmagnetic phenomena, and are of interest for their possible future applicationsin technology. In this project, the ferromagnetic response (FMR) of magnetic nanostructures to an electromagnetic excitation has been investigated using the micromagnetic simulations program Mumax3. The magnetic nanostructures in question were lattices of stadium shaped magnetic islands known as square articial spin ice. They are often characterized by the vortex in which four islands meet. Depending on the number of magnetic moment directed inwards or outwards from the vortex, four main vortex types can be created according to their magnetic energy. Lattices of square articial spin ice can exhibit articial magnetic monopoles connected by Dirac strings. Four congurations of square articial spin ice were investigated: a single stadium shaped island, two single vertices of different types, a lattice of 24 magnetic islands with two different spacings and types of center vertices, and a lattice of 60 magnetic islands for the case of inserted Dirac strings. The FMR spectra of these structures reveal several resonant modes of different intensities and frequencies. Of particular interest is the relationship between the intensity of a particular resonant mode and the number of inserted stings of reversed magnetization for the 4-by-4 lattice.