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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.
1

Seasonality in the abyssal north eastern Atlantic : a biogeochemical perspective

Mackenzie, Karen Linda January 2000 (has links)
No description available.
2

Architecture in a Northern Flood Plain

Gibson, Nancy January 2006 (has links)
The thesis is an exploration of strategies that could be utilised in creating sustainable urbanism, one in which the inhabitants retain a relationship with the environmental and geographic conditions of their place. Promoting awareness of the natural context of urban activities is necessary in an increasingly complex world that is more able to disregard the natural systems that we depend on. Sustainability is seen as crucial in terms of the economic viability of cities as well as the sustainability of the environment in which dense urban centres are situated. In the case of a city located on a flood plain, the viability of the physical and social condition of the urban centre as well as its impact on that of the surrounding region comes to the forefront each time there is a flood. The city of Winnipeg on the Red River flood plain in the central lowlands of the eastern prairie of Canada is chosen as the site for this exploration where the difficulties of freezing temperatures make the problem of building on a flood plain a greater challenge. Several methods are explored in this urban design, demonstrating that urban sustainability and environmental sustainability are not exclusive of one another. The technique of densifying and unifying elements of the urban fabric, including parks and landscaping, residential inhabitation, as well as industrial and commercial activities, can be effective for both environmental and urban sustainability. Techniques explore the incorporation of vertically integrated multi-use buildings, the movement of public areas above street level, and construction on engineered hills, stilts or with the use of floatation devices, resulting in a site specific response to urban inhabitation. The trend toward a generic non-location specific urban lifestyle is superceded in this proposal for a mode of urban dwelling reconnected with surrounding context, marked by experience of seasonal and cyclical conditions of environment inscribed by an awareness of place.
3

Architecture in a Northern Flood Plain

Gibson, Nancy January 2006 (has links)
The thesis is an exploration of strategies that could be utilised in creating sustainable urbanism, one in which the inhabitants retain a relationship with the environmental and geographic conditions of their place. Promoting awareness of the natural context of urban activities is necessary in an increasingly complex world that is more able to disregard the natural systems that we depend on. Sustainability is seen as crucial in terms of the economic viability of cities as well as the sustainability of the environment in which dense urban centres are situated. In the case of a city located on a flood plain, the viability of the physical and social condition of the urban centre as well as its impact on that of the surrounding region comes to the forefront each time there is a flood. The city of Winnipeg on the Red River flood plain in the central lowlands of the eastern prairie of Canada is chosen as the site for this exploration where the difficulties of freezing temperatures make the problem of building on a flood plain a greater challenge. Several methods are explored in this urban design, demonstrating that urban sustainability and environmental sustainability are not exclusive of one another. The technique of densifying and unifying elements of the urban fabric, including parks and landscaping, residential inhabitation, as well as industrial and commercial activities, can be effective for both environmental and urban sustainability. Techniques explore the incorporation of vertically integrated multi-use buildings, the movement of public areas above street level, and construction on engineered hills, stilts or with the use of floatation devices, resulting in a site specific response to urban inhabitation. The trend toward a generic non-location specific urban lifestyle is superceded in this proposal for a mode of urban dwelling reconnected with surrounding context, marked by experience of seasonal and cyclical conditions of environment inscribed by an awareness of place.
4

Vegetation response to fluvial activity in the Lillooet River floodplain

Teversham, Janet Mary January 1973 (has links)
This thesis attempts to determine to what extent fluvial allogenic factors affect the development of vegetation in the Lillooet Valley, north-west of Pemberton, B.C. Microenvironments exist within the floodplain, based on height, flood frequency, drainage conditions, tree cover and soil development. The area is in a constant state of flux with respect to the change of species over time and the associated nature of the river channels that cause new areas to become available while constantly destroying other vegetated areas. The major hypothesis that vegetation, both individual species and species groups, can be spatially related to elevation differences as a measure of flood frequencies, cannot be proved in isolation from other hypotheses. Mo species were found to be solely related to the elevation factor. Although six species were found to be significantly related to height, they can only be used in very general terms to estimate flood frequency, however, as it is the rare 15 to 50 year event that determines the major vegetation pattern. Pioneer, scrub and young deciduous forests on the lower elevations and the understorys of the mature forests are entirely destroyed by such an event, thus changing the direction and pace of the development of many sites markedly. The second hypothesis was that sediment type as a measure of drainage conditions is important in differentiating species distribution, especially at the pioneer stage. It has been successfully demonstrated that during initial species invasion sediment type is important. This initial spatial differentiation causes major species variation in young forests and these differences may still be noticeable in mature coniferous forests. Finally, the importance of time and associated autogenic processes was noted to be of importance. It has been shown that there are several species groups existing within the field area that reflect the age of the sediment surface, and that the sites must be discussed within the age groups for meaningful results. / Arts, Faculty of / Geography, Department of / Graduate
5

The Autecology of Celtis Laevigata in Flood Plain Forests of Denton County, Texas

Hander, Lecil B. 01 1900 (has links)
This thesis describes the present nature of one facet of some of the flood plain forest stands in Denton County, Texas. The specific purpose was to demonstrate the presence or absence of difference between the Celtis laevigata (commonly known as the hackberry, southern hackberry or sugarberry) populations in stands on Denton Creek and Elm Fork of the Trinity River.
6

A Economic Analysis of the Akkar Plain Project

Chard, E. Douglas 01 May 1981 (has links)
The purpose of this paper is to determine the economic feasibility of the Akkar Plain Agricultural Development Project. Data were collected at representative villages throughout the Akkar Plain in Syria. The data were used to establish the economic setting at the present time on the Akkar Plain and to establish a basis for determining the economic justification for the future planned developments. Methodology used was a farm budget analysis of a before development and after development situation. Internal rate of return and benefit/cost ratio were the measures used to determine economic feasibility. The paper discusses previous work completed, the development plan, methodology used, and analysis of results in that order.
7

Fragments of ars antiqua music at Stary Sącz and the evolution of the Clarist order in central Europe in the thirteenth century

Curry, Robert Michael, 1952- January 2003 (has links)
Abstract not available
8

Developing a flash drought indicator for the US Great Plains

Yang, Ze, active 2013 30 October 2013 (has links)
Flash droughts refer to those droughts that intensify rapidly in spring and summer, coupled with a strong increase in summer extreme temperatures, such as those that occurred over Texas in 2011 and the Great Plains in 2012. Climate models failed to predict these flash droughts in 2011 and 2012 and are ambiguous in projecting their future changes, largely because of models’ weaknesses in predicting summer rainfall and soil moisture feedbacks. In contrast, climate models are more reliable in simulating changes of large‐scale circulation and temperatures during winter and spring seasons. Thus, we developed and tested a physical climate indicator of the risk of “flash” droughts in summer by using the large-scale circulation and land surface conditions in winter and spring based on observed relationships between these conditions and their underlying physical mechanisms established by previous observational studies and numerical model simulations. My master research focuses on the spatial distribution of this indicator globally to see how broadly it could be applied. We also compare the different factors to see which one is the dominant contributor to drought in different area. We find that the indicator performs well at capturing the development and termination of a drought. There is much opportunity to develop and improve the indicator further. / text
9

A SURVEY ON THE EFFECTS OF PROGRESSIVE REMOVAL OF BRAND IMAGERY ELEMENTS FROM CIGARETTE PACKS ON THE PERCEPTION OF ADULT UNIVERSITY STUDENTS

Al-hamdani, Mohammed 15 August 2011 (has links)
Plain packaging can arguably reduce the appeal of cigarette packages and deter people from smoking. In this study, a 1 (brand type) X 4 (levels of plain packages) betweensubject design was utilized. The method used was an internet survey. 220 adult smokers and non-smokers from Halifax Regional Municipality (HRM) rated packages in terms of their brand imagery characteristics and answered a single multiple choice question to test their recall of the health warning on their package. According to the results of a MANOVA test and a bivariate logistic regression test of perception attributes, the association between plainer packages and the participants’ ratings for some attributes were significant, and ranged from slightly moderate to moderate strength levels of associations. Health warnings recall and plainer packages were also significantly and moderately associated. These associations provide a compelling argument for the need for plain packaging policies as a deterrent for smoking.
10

Creep of plain weave polymer matrix composites

Gupta, Abhishek 12 January 2010 (has links)
Woven (also known as textile) composites are one class of polymer matrix composites with increasing market share in aerospace, autmobile, civil infrastructure applications mostly due to their lightweight, their flexibility to form into desired shape, their mechanical properties and toughness. Due to the viscoelasticity of the polymer matrix, time-dependent degradation in modulus (creep) and strength (creep rupture) are two of the major mechanical properties required by engineers to design a structure reliably when using these materials. Unfortunately, creep and creep rupture of woven composites have received little attention by the research community and thus, there is a dire need to generate additional knowledge and prediction models, given the increasing market share of woven composites in load bearing structural applications. In this thesis, an analytical creep model, namely the Modified Equivalent Laminate Model (MELM), was developed to predict tensile creep of plain weave composites for any orientation of the load with respect to the orientation of the fill and warp fibers, using creep of unidirectional composites. The model was validated using an extensive experimental involving the tensile creep of plain weave composites under varying loading orientation and service conditions. Plain weave epoxy (F263)/ carbon fiber (T300) composite, currently used in aerospace applications, was procured as fabrics from Hexcel Corporation. Creep tests were conducted under two loading conditions: on-axis loading (00) and off-axis loading (450). Constant load creep, in the temperature range of 80–2400C and stress range of 1-70% UTS of the composites, was experimentally evaluated for time periods ranging from 1–120 hours under both loading conditions. The composite showed increase in creep with increase in temperature and stress. Creep of composite increased with increase in angle of loading, from 1% under on-axis loading to 31% under off-axis loading, within the tested time window. The experimental creep data for plain weave composites were superposed using TTSP (Time Temperature Superposition Principle) to obtain a master curve of experimental data extending to several years and was compared with model predictions to validate the model. The experimental and model results were found in good agreement within an error range of +1-3% under both loading conditions. A parametric study was also conducted to understand the effect of microstructure of plain weave composites on its on-axis and off-axis creep. Additionally, this thesis generated knowledge on time-dependent damage in woven composites and its effect on creep and tensile properties and their prediction.

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