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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.
21

Domaines vitaux et déplacements migratoires d'Aigles royaux nichant dans la région de la baie d'Hudson au Québec

Brodeur, Serge, 1961- January 1994 (has links)
The objectives of this study were to test for the feasibility of satellite radio-tracking of golden eagles (Aquila chrysaetos) breeding in the Grande-Baleine hydro-electric study area, to assess the size of their home-ranges, to determine their food habits during the nesting season, and to describe migration routes and wintering grounds of these birds. / In June and August 1992, six golden eagles, of which 5 adults (4$ rm sp{o}$ + 1 sex unknown), were caught and fixed with transmitters in order to follow their movements over one year. / The golden eagles fed on various animal species, i.e. 8 mammals, 15 birds and one fish, during the breeding season, however Canada geese (Branta canadensis) were the main item in their diet. / Four of the adult eagles undertook their fall migration in October 1992. The other adult eagle died of an unknown cause while the fate of the nestling could not be determined. All the migratory birds moved south to the United States, but they used different migration routes. The four golden eagles reached their wintering grounds in November and December, 1992. / After a three to four month stay in the wintering area, three eagles undertook their spring migration in March 1993. When returning to the breeding area, two of the eagles followed the same migration routes used in fall, while the third one flew off course to the west into Ontario. The first two birds reached their former territories in March and April while the third eagle only arrived in mid-May 1993.
22

Domaines vitaux et déplacements migratoires d'Aigles royaux nichant dans la région de la baie d'Hudson au Québec

Brodeur, Serge, 1961- January 1994 (has links)
No description available.
23

SONAGRAPHIC IDENTIFICATION OF INDIVIDUAL BREEDING BALD EAGLES (HALIAEETUS LEUCOCEPHALUS) IN ARIZONA

Eakle, Wade Laney, 1959- January 1986 (has links)
No description available.
24

Skillnader i kungsörnens (Aquila chrysaetos) flyttningsmönster beroende på ålder och klimatfaktorer : En studie för skyddet av kungsörn

Görtz, Marina January 2012 (has links)
This study examines the factors that influence the seasonal movements of Golden Eagles (Aquila chrysaetos), and can thus provide important information that helps to improve the protection of the species. There were two main purposes of this study. First, I wanted to analyze the difference between preferences of juvenile and adult Golden Eagles in their choice of southern or northern hibernation areas. Do younger eagles prefer moving longer distance to southern areas of Sweden? Second, I wanted to investigate how the climate influenced the choice of date of migration in the fall. In other words, does an early winter arrival influence the migration date of Golden Eagles? I also investigated if food availability influenced the migration date in combination with winter arrival? For the statistical analyses, 14 years (1998-2011) of data on snow conditions, temperatures, food availability and records on banded eagles from the counties Ångermanland and Västerbotten were used. I found that young eagles preferred to move further south, while adults tended to move much shorter distances or remained in the nesting area during the winter. How early or late in the fall the eagles moved was mainly affected by the first day when the temperature was -10°C or below combined with the first day when the snow depth reached at least 8 cm. Another factor that seemed to affect the date of migration was the amount of food (smaller prey), which influenced the effects of temperature and snow cover. For example, there were instances when good food availability led to eagles deciding to stay longer despite early snowfall. This important knowledge on how climatic factors and food availability influence the migration of Golden eagles can be useful when developing conservation programs for their future protection.
25

Shale Oil Production Performance from a Stimulated Reservoir Volume

Chaudhary, Anish Singh 2011 August 1900 (has links)
The horizontal well with multiple transverse fractures has proven to be an effective strategy for shale gas reservoir exploitation. Some operators are successfully producing shale oil using the same strategy. Due to its higher viscosity and eventual 2-phase flow conditions when the formation pressure drops below the oil bubble point pressure, shale oil is likely to be limited to lower recovery efficiency than shale gas. However, the recently discovered Eagle Ford shale formations is significantly over pressured, and initial formation pressure is well above the bubble point pressure in the oil window. This, coupled with successful hydraulic fracturing methodologies, is leading to commercial wells. This study evaluates the recovery potential for oil produced both above and below the bubble point pressure from very low permeability unconventional shale oil formations. We explain how the Eagle Ford shale is different from other shales such as the Barnett and others. Although, Eagle Ford shale produces oil, condensate and dry gas in different areas, our study focuses in the oil window of the Eagle Ford shale. We used the logarithmically gridded locally refined gridding scheme to properly model the flow in the hydraulic fracture, the flow from the fracture to the matrix and the flow in the matrix. The steep pressure and saturation changes near the hydraulic fractures are captured using this gridding scheme. We compare the modeled production of shale oil from the very low permeability reservoir to conventional reservoir flow behavior. We show how production behavior and recovery of oil from the low permeability shale formation is a function of the rock properties, formation fluid properties and the fracturing operations. The sensitivity studies illustrate the important parameters affecting shale oil production performance from the stimulated reservoir volume. The parameters studied in our work includes fracture spacing, fracture half-length, rock compressibility, critical gas saturation (for 2 phase flow below the bubble point of oil), flowing bottom-hole pressure, hydraulic fracture conductivity, and matrix permeability. The sensitivity studies show that placing fractures closely, increasing the fracture half-length, making higher conductive fractures leads to higher recovery of oil. Also, the thesis stresses the need to carry out the core analysis and other reservoir studies to capture the important rock and fluid parameters like the rock permeability and the critical gas saturation.
26

Development, testing and application of random walk models : case studies in red deer (Cervus elaphus) and golden eagle (Aquila chrysaetos)

Konrad, Christoph January 2012 (has links)
The attributes of landscapes, abiotic and biotic, influence the behaviour of animals. Understanding the reciprocal effects between the landscape, habitats and the animals are an essential tool in sustainable management of natural resources as well as conservation. A source of information about how the environment shapes the behaviour of animals is movement data. The advent of cheap GPS devices has facilitated data collection. The fine scale spatio-temporal resolution allows the identification of complete home-ranges, even habitat that is only transiently used. Fine-scale movement data can also be used as proxy for behaviour-types; different behaviour states cause different movement tracks. I test, extend and apply the multi-change point analysis (MCPA), developed by Gurarie et al. (2009) for the identification of behavioural change points in irregular movement data. The method relies on conventional time-series analysis methods, rather than a Bayesian framework, such as the state space models. After thorough testing of the MCPA, we apply the method and its extension to the GPS data of four red deer and 27 golden eagles. The red deer data were analysed to detect behavioural changes at a seasonal scale and to serve as a test-bed for our extension of the MCPA. The comparison of movement bouts revealed that the expression of behaviour was on a gradient rather than the discreet states. The study of the golden eagle data highlighted the necessity to choose the appropriate sampling regime of movement. If the intervals between the location-fixes are too big, valuable information about important small scale behaviour will be missed.
27

The ecology and conservation of Mackinder's eagle owls (Bubo capensis mackinderi) in central Kenya in relation to agricultural land-use and cultural attitudes

Ogada, Darcy L January 2008 (has links)
The loss of habitat to agriculture is a worldwide problem for biodiversity conservation. One species that has seemingly been able to adapt to the conversion of forests to farmlands is Mackinder’s eagle owl (Bubo capensis mackinderi), which inhabits highland areas, but little is known of its ecology, especially outside of protected areas. This study examined the impact of agricultural practices and farmer’s attitudes on the foraging and population ecology of the Mackinder’s eagle owl in central Kenya. Owl territories were monitored monthly from June 2004- October 2006 for signs of occupancy, breeding activity, mortality and to collect data on food resources. Nest site characteristics were measured for all known nests. Because previous studies showed an affinity for rodents, small mammals were trapped monthly using mark-recapture methodology. In each territory, the type and amount of farm crops were measured each month and farmers were interviewed about their knowledge and beliefs about owls. Mackinder’s eagle owls in central Kenya lived at extremely high density 0.87 owl pairs/km². This density was high compared to other populations of Mackinder’s eagle owl and to Eurasian eagle owl (Bubo bubo) populations in Europe. Breeding success was 48% over three years and this compared well with other species of eagle owl inhabiting human-disturbed areas. All nests and roosts were located in river valleys, and all successful nest sites were located on cliffs or other inaccessible rocky terrain. Nest sites were located adjacent to farms, which provided for both open hunting and an abundance of prey. Breeding activity was concentrated after the rainy seasons and this was likely linked to prey availability after the rains. Agricultural activities generally had a positive effect on rodent populations. Small mammal trapping results revealed that rodents were over 14 times more abundant in farms than in adjacent grassland habitat. This population of Mackinder’s eagle owl had a very catholic diet and consumed mostly mammalian prey species including hares, giant rats, root rats, grooved-tooth rats and small rodents. Small rodents accounted for almost half of the owls’ diet and when their numbers increased, owls responded by consuming more of them, indicating the importance of farming activities to this population of owls. Other populations of eagle owl inhabiting human-disturbed areas had diet widths positively related to levels of habitat disturbance. This result supported optimal foraging theory that more productive environments have predators with more specialized diets, while patchy environments have generalist predators. The ecology of this population of Mackinder’s eagle owls was heavily influenced by human agricultural activities, which generally had a positive effect on their population. Farming activities changed rapidly both within and between seasons as plots were small and neighbouring farmers planted various crops at different times of the year and this was enhanced by irrigation in some areas. Year-round availability of forage within farms had a positive effect on owl prey species, some of which increased relative to the type and amount of crops found in farms. However, 57% of owl injuries and mortalities that occurred were related either directly or indirectly to human activities. Cultural prejudices against owls remain the biggest threat to this population’s long-term persistence. Farmer education was shown to play a significant role in overcoming negative beliefs about owls. Because Mackinder’s eagle owls are highly adaptable to anthropomorphic landscape changes, largely due to their adaptability as food generalists, they are one of the few top predators remaining in this highly disturbed agricultural system. However, populations within agricultural areas remain especially vulnerable to negative human attitudes towards owls due to their close association with human activities.
28

3D zobrazovací jednotka / 3D display device

Varga, Tomáš January 2012 (has links)
Based on binocular vision the human eye is capable of generating the observed spatial perception of the object. Nowadays 3D imaging of two-dimensional surface is in vogue especially in the cinema industry. However, 3D imaging is gradually getting into other industries especially in other parts of everyday life (advertisements, presentations, entertainment ...). 3D images can be created in various ways, some of which are detailed in this master´s thesis. This thesis deals with the description and the drawing up of a 3D display which provides a three-dimensional image without using auxiliary objects such as glasses. The display unit produces a three-dimensional image at a fundamental level, which consists of providing high-speed rotation of the display and creates the current portion of the object in specified sections.
29

The influence of rainfall on the Verreaux's eagle and its prey species in the Matobo hills, Zimbabwe

Nkomo, Merlyn 07 March 2022 (has links)
Understanding how species respond to variations in weather patterns will be crucial to improve our predictions about how species will cope with climate change. The Verreaux's Eagle (Aquila verreauxii) and its primary prey species the Rock Hyrax (Procavia capensis) and Yellow-spotted Hyrax (Heterohyrax brucei) have been monitored by a long-term citizen science project in the Matobo Hills, Zimbabwe. A previous study associated rainfall patterns with the establishment, breeding density and productivity of Verreaux's Eagles. Fluctuations in hyrax populations have been attributed to fluctuations in rainfall and drought. However, these studies have been limited by the use of total annual rainfall instead of targeted rainfall periods of when biological outcomes are most sensitive to weather phenomena. This study explored critical climate sensitivity windows influencing the Verreaux's Eagle's reading performance and the abundance of its main prey species. We used observations of 109 nests over 37 years (1984-2019) and counts from 20 hyrax den sites for 13 years (1993-2005), together with remotely sensed rainfall data. The probability of attempting to breeding and the probability of producing a fledgling was negatively associated with rainfall. For breeding attempt, the rainfall during June and July, 11-10 months before laying was the most relevant, whereas, for productivity, the rainfall during December to March, nine-five months before fledging was the most relevant. However, the relationship between the rainfall signal and breeding productivity was not significant. Hyrax abundance had a negative quadratic relationship with mean rainfall against their respective climate windows, whereby the abundance of adult and sub-adult hyrax increased with rainfall during July–September but declined thereafter at greater rainfall levels. The abundance of hyrax did not have a significant relationship with the breeding outcomes of the Verreaux's Eagles. This study shows the complexity of the causal relationships between climate and biological outcomes and also the value of long-term data to understanding the impacts of variations in weather patterns to better understand predator-prey dynamics.
30

The Adventures of Eagle Feather: A Collection of Stories

Goebel, Luke B 01 January 2010 (has links) (PDF)
Luke Goebel wrote this collection of fiction in his final year enrolled at the M.F.A. Program for Poets and Writers at the University of Massachusetts Amherst. These stories were wrought after studying with Sam Michel, Noy Holland, as well as other faculty members at UMass Amherst, and after a summer of study with Gordon Lish. The themes that recur throughout these stories are: fathers, America, Bald Eagles, feathers, Native American mythology and legend (obsession with Native Culture), as well as sex and sexual awakening/revulsion, and, of course, the road.

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