Thesis (M.S.)--Oregon State University, 2005. / Printout. Includes bibliographical references (leaves 45-48). Also available via the World Wide Web.

Thesis (M.S.)--Florida State University, 2005. / Advisor: Sherwood W. Wise, Jr., Florida State University, College of Arts and Sciences, Dept. of Geological Sciences. Title and description from dissertation home page (viewed Jan. 27, 2006). Document formatted into pages; contains ix, 93 pages. Includes bibliographical references.

Experimentos têm revelado que redes de neurônios, tanto in vitro como in vivo, mantêm atividade descrita por avalanches e se organizam em um estado crítico no qual essas avalanches são distribuídas de acordo com leis de potência. Mostramos no presente trabalho que um modelo de rede de elementos excitáveis com sinapses dinâ- micas é capaz de exibir criticalidade auto-organizada para ampla região do espaço de parâmetros. Nossos resultados estão de acordo com outros estudos que indicam que a depressão sináptica de curto prazo constitui mecanismo suciente para produzir criticalidade em avalanches neuronais. No entanto, segundo diversos pesquisadores, embora o ajuste de parâmetros seja grosso para que haja criticalidade no modelo, é mais preciso dizer que o sistema não apresenta criticalidade auto-organizada genu ína, mas sim quasi-criticalidade auto-organizada, como os demais modelos não conservativos presentes na literatura. / Experiments have shown that neuronal networks, both in vitro and in vivo, maintain activity described by avalanches and they are organized into a critical state in which these avalanches are distributed according to power laws. We have demonstrated that a model based on a network of excitable elements with dynamical synapses is able to exhibit self-organized criticality for a wide range of the parameter\'s space. Our results are consistent with other studies that suggest short-term synaptic depression is enough to produce criticality in neuronal avalanches. However, according to several researchers, in spite of the tuning to be gross to ensure that there is criticality in the model, it is more accurate do not say that the system presents genuine self-organized criticality, but self-organized quasi-criticality as the other non-conservative models in the literature.

Snow glide is the translational slip of the entire snow pack over a sloping ground surface. It is thought that rapid rates of snow glide precede the release of full-depth avalanches. The nature of avalanches that release at the ground makes them difficult to predict and difficult to control using explosives. The aim of this research is to determine the relationship between rapid snow glide and full-depth avalanche occurrence and to examine climate factors affecting both processes. Data collected from an instrumented site along the Coquihalla Highway in the Cascade Mountains of British Columbia were used for analysis during two winter seasons (1992-93, 1993-94). Glide is influenced by the nature of the interaction between the roughness of the ground and the snow pack, and by the distribution of water at the interface. The presence of water at the interface affects the material properties of snow and the friction conditions. The impact of freewater on glide is influenced by the volume and rates of water input. Higher glide rates and fulldepth avalanche release are the almost immediate responses to contributions of free-water. The data show that the most significant contributor is rainfall, which is common in the study area throughout the winter season. The supply of free-water from snow melt due to radiative and thermal sources of energy become more significant in the spring. Water inputs increase the thickness of the saturated layer at the base of the snow pack, allowing greater amplitudes of roughness to be overcome. By drowning or partially drowning the roughness elements, a thin film of water reduces the shear resistance of the snow pack to downslope movement. Inputs of water at rates higher than transmissions rates will increase pore pressures and decrease shear stress encouraging further downslope movement. Failure of the snow pack at the ground is translational, most often occurring 12-24 hours after a rainfall event, but sometimes much later when avalanche release would not be expected. Although there is no threshold glide velocity associated with avalanche release, it can be concluded that snow glide is a good indicator of active periods of full-depth avalanche occurrence. However, results from this study show that rainfall rates and snow melt rates may be more accurate predictors of avalanche occurrence in the study area.

Thesis (M.S.)--University of Wyoming, 2007. / Title from PDF title page (viewed on Nov. 11, 2008). Includes bibliographical references (p. 85-86).

Thesis (PhD)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Katherine J. Hansen. Includes bibliographical references (leaves 325-338).

Snow glide is the translational slip of the entire snow pack over a sloping ground surface. It is thought that rapid rates of snow glide precede the release of full-depth avalanches. The nature of avalanches that release at the ground makes them difficult to predict and difficult to control using explosives. The aim of this research is to determine the relationship between rapid snow glide and full-depth avalanche occurrence and to examine climate factors affecting both processes. Data collected from an instrumented site along the Coquihalla Highway in the Cascade Mountains of British Columbia were used for analysis during two winter seasons (1992-93, 1993-94). Glide is influenced by the nature of the interaction between the roughness of the ground and the snow pack, and by the distribution of water at the interface. The presence of water at the interface affects the material properties of snow and the friction conditions. The impact of freewater on glide is influenced by the volume and rates of water input. Higher glide rates and fulldepth avalanche release are the almost immediate responses to contributions of free-water. The data show that the most significant contributor is rainfall, which is common in the study area throughout the winter season. The supply of free-water from snow melt due to radiative and thermal sources of energy become more significant in the spring. Water inputs increase the thickness of the saturated layer at the base of the snow pack, allowing greater amplitudes of roughness to be overcome. By drowning or partially drowning the roughness elements, a thin film of water reduces the shear resistance of the snow pack to downslope movement. Inputs of water at rates higher than transmissions rates will increase pore pressures and decrease shear stress encouraging further downslope movement. Failure of the snow pack at the ground is translational, most often occurring 12-24 hours after a rainfall event, but sometimes much later when avalanche release would not be expected. Although there is no threshold glide velocity associated with avalanche release, it can be concluded that snow glide is a good indicator of active periods of full-depth avalanche occurrence. However, results from this study show that rainfall rates and snow melt rates may be more accurate predictors of avalanche occurrence in the study area. / Arts, Faculty of / Geography, Department of / Graduate

No description available.

Thesis (M.S.)--University of British Columbia, 2000. / "September 2000." Title from front page; viewed on 6/6/02. Displays in grey scale. Includes bibliographical references (p. 39-42).

Thesis (M.S.)--Brigham Young University. Dept. of Geology, 2003. / Includes bibliographical references (p. 38-40).