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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.
221

The paleoecology of stromatoporoids from the southeast margin of the Miette carbonate complex, Jasper National Park, Alberta, Canada.

Kobluk, David R. January 1973 (has links)
No description available.
222

Co-management re-conceptualized: human-land relations in the Stein Valley, British Columbia

Wilson, Madeline 06 May 2015 (has links)
Across Canada, and in many places around the world, cooperative management arrangements have become commonplace in land and resource governance. The Stein Valley Nlaka’pamux Heritage Park, located in south-central Interior British Columbia, is one such example. An unlogged, undammed watershed, the Stein Valley became the site and subject of protests over proposed logging between the 1970s and 1990s. It lies within the territories of the Nlaka’pamux Nation and, since its park designation in 1995, has been jointly managed by the Lytton First Nation and the Provincial Government through a Cooperative Management Agreement. This thesis traces human-land relations throughout the history of the Stein Valley in order to theorize an expanded conception of co-management. The central goal is to understand how various co-management arrangements are formed, contested, and enacted through particular land-use practices, social and institutional interactions, and socio-ecological relationships. Through a detailed reading of the socio-ecological history of the Stein Valley, drawn from semi-structured interviews and a literature survey, this thesis adds to existing scholarship on B.C. environmental politics. In this project, I locate various co-management practices at work in the Stein Valley region—including but not limited to practices of use, stewardship, and governance compelled by legalistic co-management arrangements. Ultimately, this thesis calls for a closer examination of the myriad of practices and relations embedded within land and resource management regimes. In doing so, it resituates the agency of various actors, and their ecological interactions, in producing, governing, and shaping the socio-ecological landscapes we both inhabit and actively create / Graduate
223

Geopiety and landscape perceptions at Mounds State Park, Anderson, Indiana

Perry, Barbara January 2003 (has links)
This study provides an examination of landscape perceptions, specifically geopiety or sacred landscape perceptions, at Mounds State Park. Through archival analysis I traced 2000 years of landscape perceptions at the park and found that geopiety has been an underlying influence in shaping perceptions. I further examine contemporary perceptions at Mounds state Park through participant observation and ethnographic interviewing and have determined that geopiety continues at the park in the form of nature-centered, historical/cultural and recreational perceptions. Finally, I examined the influence of modernity on geopiety and have determined that the level of geopiety is determined by the degree an individual is influenced by modernity. Modernity exists in varying degrees from traditional to progressive with the majority of individuals couched within the “inbetweeness” of modernity. / Department of Geography
224

Cridge Park tent city from the perspectives of participants

Sargent, Cristal 18 January 2012 (has links)
There is a growing body of research on homelessness, and collective action amongst the homeless. Tent cities are examples of self-help housing efforts. Tent cities are erected as shelter and make poverty visible in public domains. The form and interaction of tent cities are context specific. The perceptions of tent city participants in Canada remain partly understood by researchers. The aim of this thesis is to investigate activism and collective mobilization in one tent city – Cridge Park tent city - from the perspectives of tent city participants. I questioned what the experiences in the tent city meant for participants, their perceived public reaction to the tent city, and whether the research participants continue their activism beyond Cridge Park tent city. I present an empirically-grounded case study to uncover four participants’ perspectives of their involvement. I used qualitative research methods to access the perspectives of tent cities from four Cridge Park tent city participants. Cridge Park participants spoke of Cridge Park tent city as a “community” where they enjoyed freedom to negotiate their individual identity and where they found security and safety, which they lost when the tent city was closed. Including houseless persons in the decision-making process for services and policies that directly impact them is required to better meet their needs. Comparative research could investigate contextual differences and influences on the success or failure of tent cities as forms of social movement activities. / Graduate
225

The technological and aesthetic impact of computer-generated images on the Hollywood cinema

Napleton, Steven January 2000 (has links)
The cinema, as originally an analogue apparatus of representation, has a particularly complex and contradictory relationship to the incursion of new digital practices and potentialities. This thesis examines this relationship through a study of the impact of computer-generated images (CGI) on the Hollywood mode of production, and on its visual and narrative filmic codes. Computer animation is unquestionably a technology of digital simulation, and its initial presence is necessarily based on an aesthetics of simulation, visually separating, and diegetically demarcating, the digital image as virtual and artfficial. Consequently, most previous accounts of CGI have focused predominantly on films depicting cyberspace and VR, such as Tron and The Lawnmower Man, within the parameters of debates on special effects, the generic conventions of science fiction, and postmodern concerns with virtuality and simulation. In the early 1 990s, however, technological innovations facilitated the transition to an aesthetics of photorealism, emphasising the seamless compositing and integration of CGI characters, objects and environments with live-action. The thesis argues that the this shill is fundamental in establishing the commercial and aesthetic credibility of CGI as a production tool, and it is closely examined through a case study of Jurassic Park. The processes by which the first organic, photorealistic CG characters were created are analysed, with particular reference to the role of procedural and hand methods of computer animation in constructing a new virtual aesthetics. The integration of CGI as a production tool is also related to the diegetic presence of information technologies as narrative devices, and the extra-textual commercial and professional discourses through which CGI is explicated and celebrated. The thesis argues that the cinema is able to exploit the potential of digital methods, whilst simultaneously displaying a fundamental anxiety over the status of its own representational codes. Finally, strategies of visibility and virtuality in computer animation are further examined in the context of the emerging digital mode of production in Hollywood, and of the high concept film's role in multimedia marketing and distribution strategies
226

The role of termites in the ecology of Tsavo National Park, Kenya

Buxton, Robin January 1979 (has links)
Tsavo National Park lies in an area of very dry country in South Eastern Kenya. Elephants live there in large numbers and in the early 2 1970's, they had a mean population density of about 1 km<sup>-2</sup> . They have inflicted widespread destruction on the woodlands which originally covered the Park, leading to a complete change in the appearance of the habitat. This caused considerable anxiety about the future of the Park and all its animal populations so research was begun to try to elucidate the root causes of the "elephant problem" and to predict its consequences. The purpose of the present study was to find out what happens to dead wood in Tsavo and to gauge the importance of termites in the ecology of the area. Section 1 gives a brief introduction to the history of Tsavo and sets out the main questions posed when this study was begun. In Section 2 the environment of the study area is described in terms of its topography and geology, the soils and their origins, the floristic and structural composition of the vegetation during this study, the climate and its variations in time and space and the role of fire in shaping the habitat. The species of termites found in the study area are listed in Section 3, followed by brief descriptions of their natural history. Section 4 contains all the information on the turnover of dead wood. The standing crop and rates of wood fall and removal were measured directly at one site and extended by means of an index to measure consumption of dead wood by termites at other sites. Consumption is found to be related to rainfall. The results are discussed in relation to similar studies made elsewhere. A model is constructed relating the consumption of dead wood by termites to rainfall and comparing this with the consumption of grass and browse by large herbivorous mammals. A method is described for measuring the relative importance of different termite species as consumers of dead wood.
227

The habitats and feeding stations of birds in Tsavo National Park, Kenya

Lack, Peter C. January 1980 (has links)
The land-bird community of Tsavo East National Park was studied for two years. There are two wet seasons each year: November-December and April- May, but the latter were very poor in both study years. Six habitat types were designated on the basis of canopy cover of woody vegetation. Riverine vegetation was also studied. Most ofthe open habitats extant are derived from woodland by destruction of trees, a process largely caused by elephants. Food supplies are seasonally variable. Insects and grass seeds are most abundant in December and January. In the open habitats the few fruits also peak then, but Commiphora spp., which is only in woodland and is the most abundant fruit in Tsavo, peaks July to September. The ecology of each species of land-bird is described and most are found to be ecologically separate from each other. The annual cycle of numbers of birds in each habitat is closely correlated with the food supplies. In the open habitats birds are almost all insectivorous, granivorous or both, and peak numbers (about five times the dry season density) occur in December and January. In woodland, numbers remain fairly constant through the year and frugivores are more prominent, especially around August. The wet season peaks in all habitats are caused by immigrations of different species, both from elsewhere in Africa most of which come in to breed, and species which breed in the Palaearctic. The August peak in Woodland consists mainly of species which have resident populations. The results are particularly related to the recent habitat changes in the Park. They are compared with other bird studies in African savannas and other components of the Tsavo ecosystem. Finally, the means by which birds are able to survive in the harsh and unpredictable conditions of Tsavo are discussed.
228

A novel framework for the analysis of low factor of safety slopes in the highly plastic clays of the Canadian Prairies.

2014 September 1900 (has links)
The most common way to analyze slope stability is to employ limit equilibrium (LE) theory and obtain a factor of safety (FOS). Methods of LE analysis balance the forces, and/or moments that are driving and resisting slope movement. Generally, in geotechnical engineering practice, a slope that plays host to an important structure is designed with a minimum factor of safety (FOS) of 1.5 and slope movement is monitored throughout the structure’s serviceable life. No further analysis of slope stability is completed until failure occurs when a back analysis is undertaken for the design of remedial measures. This thesis builds on current methods to demonstrate a framework for analysis that can be followed to analyze the state of a slope throughout its serviceable life. The two bridges at North Battleford, Saskatchewan (Battlefords bridges) were used as case studies for this work. In 1967, the older of the two bridges experienced a slope failure at its south abutment immediately prior to its opening to the public. The failure was remediated reactively by means of subsurface drainage, a toe berm, and river training that included diversion/spur dikes to reduce scour at the landslide toe. Since remediation, there has been no other catastrophic failure at either bridge but slow movement continues in the south abutment slope. Laboratory data and field observations from the onsite inclinometers were provided by Clifton Associates Ltd. (CAL) and Saskatchewan Ministry of Highways and Infrastructure (SMHI). The following methodology was followed to develop a framework of analysis for low FOS slopes: 1. Synthesis of data collected during previous investigations at the Battlefords bridges; 2. Detailed site characterization using existing research and terrain analysis; 3. Back analysis of the critical section through original failure using traditional limit equilibrium methods to calibrate the soil strength properties; 4. Application of the calibrated soil strength properties to the original failure after remediation; 5. Estimation of unknown soil properties using instrumentation at the site. 6. Create a model of the new bridge south abutment with the calibrated strength properties from steps 4 & 5 using the finite element method (FEM). 7. Confirmation of the mechanism of failure and assessment of the shear strain and mobilized shear strength; and, 8. Comparison of the results of FEM and LEM models and relationship between factor of safety and mobilized shear strength. The framework presented in this thesis presents a method of modeling the instability of a slope. In the absence of triaxial testing data, it presents a range of mobilized shear strengths along the shear plane.
229

Statusbedömning av asynkronmotorer

Dicksen, Peter, Brännholm, Arvid January 2015 (has links)
Induction motors, often referred to as the workhorse of the industry, play an important role in production today. Therefore, it's important to diagnose any faulty induction motor prior to failure to avoid costly and time consuming production stops.This thesis compares methods for diagnosing induction motors in operation, MCSA, Park's vector approach and the standard method used by Swedish industries today. By simulating broken rotor bars and short-circuit in one of the windings, each method is tested and the results are compared using matlab.The results need further verification due to uncertainties of the condition of the test motor, even though the experiment gives a hint of the different advantages of each method. A combination of the methods should be able to tell if the motor needs further examination.
230

Suitable Habitat Modelling for the Yellow-breasted Chat (Icteria virens virens) in Point Pelee National Park, Canada.

Walker, Jessica Rose January 2012 (has links)
In order for conservation managers to preserve species within an area, an in-depth knowledge of the distributional patterns of focal species within a landscape is required. This is especially true when the species of concern is Threatened or Endangered and conservation of habitat is essential for species preservation. The yellow-breasted chat (Icteria virens virens) is one such species that is listed as Special Concern under the Species at Risk Act of Canada; the virens subspecies meets the criteria for Endangered. Populations within Canada are limited due the bird’s natural range, which extends north into the extreme southern part of Ontario. Point Pelee National Park is one of two strongholds for this species. However, populations within the park have been declining greatly over the past few years with a 70% rate of decline between 1982 and 2008 (n =10, n=3). This decline is likely due to the lack of natural disturbance such as fire, as well as land use change to agriculture and urbanization that has resulted in a decrease of suitable habitat, outside the park. To examine these hypotheses, habitat suitability modelling is a useful tool. It offers conservation managers insight into current distributions of species, especially species of concern. The purpose of this research was to examine environmental variables relating to three bird species and use these variables to model suitable habitat within the study site (Anders Field Complex). In my study, ArcMap 10 was used to model and map suitable habitat within the Anders Field Complex of Point Pelee National Park, as this is the last known nesting grounds for the yellow-breasted chat within the park. The willow flycatcher (Empidonax traillii) and the white-eyed vireo (Vireo griseus) were also studied as they fill a similar niche and therefore strengthen the results of the study. Environmental variables were modeled to predict suitable habitat and therefore predict potential species distribution. The model used predictors such as vegetation composition of breeding territories and nest patch vegetation composition to identify potential suitable habitat within the study site. Results of the models show that there is likely no suitable habitat (0.04 ha) available for the yellow-breasted chat within the complex. Some suitable habitat was available for the willow flycatcher but seemed limited within the study site (4.1 ha), while an absence of available data on nest scale vegetation characteristics rendered modelling of the white-eyed vireo’s habitat moot. Conditions within the Anders Field Complex have succumbed to succession resulting in mature conditions in vegetation structure and composition, as low dense shrub with high herbaceous cover is being replaced with tall thicket with very little ground cover. Height of vegetation has succeeded the requirements of the yellow-breasted chat. These results show that habitat succession and therefore the loss of suitable habitat is a likely factor influencing chat populations within the Anders Field Complex. There are also factors outside the park likely affecting chat distribution including habitat loss and fragmentation at the landscape scale. Management practices, such as the re-introduction of lost mechanisms or processes within the park should focus on a broad-scale ecological approach that considers novel thinking to restoring ecological integrity. Human induced influences including land use change and introduction of exotic species have forever changed conditions within and surrounding the park, therefore restoration should be mindful to new ecosystems, as restoring to past conditions is likely unproductive. Implementing a disturbance regime such as prescribed burnings, is recommended in order to restore a lost mechanism for the renewal of early-successional habitat. Concentrating on restoration of ecosystems and the re-establishment of a shifting mosaic will provide habitat for a plethora of species including the chat, which is legally mandated by law. However, restoring habitat for the chat will likely not result in the increase of chat abundance within the park until factors outside of the park, including habitat loss and fragmentation are rectified.

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