1,498 research outputs found

    Measurement of planar refractive index profiles with rapid variations in glass using interferometry and total variation regularized differentiation

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    Planar refractive index profiles with rapid variations, formed in glass, are measured with interferometry. This involves forming a bevel in the glass and orientating the fringe pattern to be normal to the bevel edge. The index profile is determined by differentiation of the phase function of the fringe pattern. The differentiation has been performed using the total variation regularization method in order to preserve rapid changes in the derivative. This new approach avoids the necessity of filtering, in order to reduce noise, in the direction perpendicular to the bevel, which would otherwise smooth out the rapid index changes. The method is assessed using a model refractive index profile that contains an index gradient of 0.24 ?m?1 and is then applied practically to measure the refractive index profile of electrically poled BK7 glass. The new approach allows the sharp transition in the index between poled and unpoled glass to be observed as well as the accumulation of potassium ions beyond the poled glass region

    The analysis of the spatial patterns and controls governing the global occurrence of fatal landslides

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    In the research presented here, a global inventory of fatal landslides has been generated allowing the investigation of the spatial distribution and temporal occurrence of mass movement events. There are important regional differences within these data with Asian fatalities being characterised by high frequency, low magnitude landslide events. In comparison, high magnitude events were found to be responsible for the high fatality totals in the Americas. This research has demonstrated that the spatial distribution of fatal landslides is best explained by a combination of physical and social factors and has yielded some interesting results.87% of the fatal landslide events recorded within the database were triggered by high intensity of prolonged rainfall events associated with tropical cyclones or monsoon rainfall that are compounded in areas of high relief associated with tectonically active mountain belts. Increasing landslide impacts are often associated with less developed countries, where there is rising population density, rural to urban migration, growth of megacities, and severe land degradation. However, the results indicate that the occurrence of landslide fatalities are not simply a function of level of development of a country or population density but that fatalities predominantly occur within middle income countries and rural areas which are increasingly vulnerable to landslide disasters. This can be attributed to changes in physical systems, most notably climate variation

    Landscape, Livelihoods and Risk: Community Vulnerability to Landslides in Nepal

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    The occurrence of fatal landslides in Nepal is increasing with time, faster than the effects of monsoonal variations. Possible explanations for the trends observed include: land-use change, population growth, and the development of transport infrastructure. However, to date, there is little evidence to support these postulated causes and very little research into the nature of landslide vulnerability in the Nepalese context. This research takes an interdisciplinary approach to examine, and where necessary, challenge a series of assumptions made regarding landslide vulnerability in Nepal with a view to developing a better understanding of social vulnerability and its underlying causes. Firstly, a bottom up livelihoods based approach is adopted to examine the following research questions: (1) Who is vulnerable to landslide hazard?; (2) Why do people occupy landslide prone areas?; and (3) How do ‘at risk’ rural communities perceive and respond to landslide hazard and risk? In so doing, this thesis approaches the question of landslide vulnerability from the perspective of the vulnerable people themselves. Secondly, the research explores how scientists and policy experts view landslide risk management in Nepal and how policy is subsequently informed and shaped. The findings highlight the impact of infrastructure projects in rural Nepal. Within the Upper Bhote Koshi Valley clear transitions in settlement patterns and rural livelihoods (and thus the occupation of landslide prone areas) have been seen over time. For the majority of households, their decision to occupy these areas is driven by the economic and social benefits associated with the road. Landslide risk therefore emerges not just from societal marginalisation but also from situations of relative prosperity. The findings suggest that occupants of landslide prone areas have a good understanding of landslide hazard and its associated risk. However, these risks are contextualised in relation to other social concerns. The significance of the findings for landslide policy and practice are addressed along with different actors’ views of landslide risk management in Nepal

    Sandwich compounds of titanium

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    Signal processing in slit-scan flow cytometry of cell conjugates

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    The design and implementation of a real-time signal processing system for slit-scan flow cytometry is described. The system is used to measure the separate scatter and fluorescence peak heights of 2 adherent cells. Preliminary measurements of changes in the membrane potential induced by interactions between natural killer (NK) cells and their target cells are presented

    The neglected country(side): Earthquake risk perceptions and disaster risk reduction in post-Soviet rural Kazakhstan

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    © 2020 The Authors While increasing resilience to earthquakes in the global South has become a major research and policy goal, the focus has largely been on rapidly expanding urban areas. Rural areas are often neglected despite the fact that rural residents make up a significant proportion of the population exposed to earthquakes in many low and middle-income countries. Central Asia is a case in point. Drawing on empirical research undertaken in the Central Asian Republic of Kazakhstan, this paper explores local perceptions of and responses to earthquake hazard and risk among rural householders. The primary data are derived from a survey of 302 households conducted across six rural communities in South Kazakhstan oblast (now Turkistan oblast), supplemented by 10 focus group discussions with rural residents. The findings show little awareness of earthquakes or concern about the potential occurrence of a high magnitude earthquake in the future. This reflects, at least in part, a lack of direct experience of all but minor earthquakes. As a result, we see little evidence of the presence of a seismic culture. Only a small number of respondents had received guidance on how to prepare for, or respond to, earthquakes, and few householders had taken any action to reduce the risk faced. We reflect on the findings in the context of Kazakhstan's Soviet past and its transition to a post-Soviet future. We argue that acknowledging this past is essential to understanding local level decision-making and to informing future disaster risk reduction interventions in rural areas

    Cooking with Glass Ovenware

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    The pamphlet was produced by the makers of Phoenix Glass Oven Ware. There is a preface written by M.S. Bruce McGee, Principal of the Midland School of Domestic Science, Birmingham where Phoenix Glass Oven Ware is promoted as an ideal wedding gift. There is a wide ranging selection of recipes using the glass ware. There is a reciept for goods recieved from Dockrell Sons & Co. Ltd. Dublin, dated 1939 and addressed to Mrs Lyons of Blackrock, Co. Dublin

    Sandwich compounds of titanium

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