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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

Owl Inspired Leading Edge Serrations for Gliding Flight

Galvez, Derius Jamal 10 August 2018 (has links) (PDF)
When considering smaller scale UAV’s there is not a lot available that could survey large areas quickly, stealthy, and with a considerable range. Owls have an interesting trait that is not found in most avian species; leading-edge serrations. These serrations give owls the ability to fly silently and steadily without sacrificing maneuverability. The focus of the research was to design leading-edge serrations that would improve the flight performance of a Styrofoam glider. Previous studies defined serrations by the inclination angle, tip-displacement angle, and the length of the serration in the x-y plane. Using these parameters, a serration mold was computer modeled and 3D printed from a resin material. Silicone was used to cast the mold, allowing flexible serrations to be created. The serrations were fitted onto the leading-edge of a Styrofoam glider which was used for flight testing. Flight test between serrated and non-serrated leading-edge gliders are presented and compared.
22

Local weather, regional climate, and population dynamics of northern spotted owls in Washington and Oregon /

Glenn, Elizabeth M. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 253-266). Also available on the World Wide Web.
23

Výr velký (Bubo bubo, Linnaeus, 1758) jako modelový druh pro environmentální výchovu / Eagle Owl (Bubo bubo, Linnaeus, 1758) as a Model Species for Environmental Education

Žmolil, Matouš January 2019 (has links)
This diploma thesis deals with an eagle owl as a model species for environmental education. The first part focuses on this species and how it was perceived in the past and the possible reasons for its pursuit. The second part focuses on the progressive return of this owl to Czech nature and legal measures to protect it. In the third part the thesis focuses on the presence of eagle owl in neighbouring countries of the Czech Republic and their latest states and legal measures. The last and practical part is focused on the perception of secondary forestry students and grammar school students on the return of selected vertebrates to Czech nature. This part focuses mainly on comparing the perception of eagle owl to other vertebrates in Czech nature.
24

Influence of local and landscape characteristics of Prairie Dog colonies on Burrowing Owl nest ecology in South Dakota

Bly, Kristy Lee Sydney. January 2008 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Mark Taper. Includes bibliographical references.
25

Nest site selection of California spotted owls (Strix occidentalis occidentalis) in the Lassen National Forest analyzed at several spatial scales

Berigan, William John. January 2009 (has links)
Thesis (M.S.)--California State University, Chico. / Includes abstract. "Located in the Chico Digital Repository." Includes bibliographical references (p. 64-69).
26

The range expansion of the northern barred owl : an evaluation of the impact on spotted owls /

Kelly, Elizabeth G. January 2001 (has links)
Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 41-44). Also available via the World Wide Web.
27

Habitat connectivity and spotted owl population dynamics /

Schumaker, Nathan H. January 1995 (has links)
Thesis (Ph. D.)--University of Washington, 1995. / Vita. Includes bibliographical references (leaves [74]-80).
28

Generalized linear mixed models with censored covariates /

Giovanini, John. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references. Also available on the World Wide Web.
29

Kosterní zbytky v potravě kalouse ušatého Asio otus (Linnaeus,1758) jako ukazatele populačních změn drobných savců na zimovišti v Kladně-Kročehlavech / Telemetry of the Long eared owl (Asio otus) in the wintering place in Kladno

Kolomazníková, Jana January 2011 (has links)
23/6/2011 Kosterní zbytky v potravě kalouse ušatého 7 jako ukazatele populačních změn drobných savců 1.2 Abstrakt v anglickém jazyce The diploma thesis is called Skeletal Remnants in Diet of Long-eared Owl Asio otus (Linnaeus, 1758) as The Indicators of Fluctuation in Size of Population of Small Mammals in Wintering Place in Kladno-Kročehlavy. The thesis deals with oversight of Long-eared Owl in his wintering site, analysis of his diet, and estimation of population changes in the diet of small vertebrate. It also consists of the estimation of changes in gender of small mammals and in the content of his diet, and of studies morphological traits done on pelvises of males and females of common vole. As part of didactic section there were laboratory exercises completed. The focus was on the analyses of pellets and the assignment of small vertebrates in the diet of Long-eared Owl. The main monitoring was completed in the period of autumn 2009 till the end of winter 2010. The results showed significant changes in the population of small mammals included in the diet of Long-eared Owl could bring new knowledge about population dynamics of small mammals. Another part of monitoring of population of Long-eared Owl was also tramping and ringing. Most of the materials used for this analysis of the diet came from the...
30

Diet and habitat of the powerful owl (Ninox strenua) living near Melbourne

Lavazanian, Elizabeth, elizabeth.lavazanian@deakin.edu.au January 1996 (has links)
The diet of Powerful Owls (Ninox strenua) living at Christmas Hills, 35km north-east of Melbourne was examined by analysis of 686 regurgitated pellets collected over two years. An aid was also developed to help identify potential mammalian prey species based on hair and skeletal characteristics. The following features were found to be most useful in distinguishing between the three species of arboreal marsupials - Common Ringtail Possum (Pseudocheirus peregrinus), Common Brushtail Possum (Trichosurus vulpecula) and Sugar Glider (Petaurus breviceps): - Cross-sectional width of primary guard hairs. - The size and shape of the nasal, frontal, parietal and squamosal bones of the skull. - Dentition. The size and shape of the upper incisor, canine and premolar teeth. The size and shape of the lower incisor and premolar teeth. - The size of the humerus. The Sugar Glider has a much smaller humerus than that of the Common Ringtail Possum and the Common Brushtail Possum. In the Common Brushtail Possum the entepicondyle ends in a very sharp point but the Common Ringtail Possum this point is not as sharp. - The Common Ringtail Possum’s femur has a very prominent trochanter which projects further than that in the Common Brushtail Possum. The femur of the Sugar Glider is distinguished by having a very large depression between the condyle and the trochanter. - The Common Brushtail Possum’s scapula has a narrower lower blade (relative to length) than that in the Common Ringtail Possum. The scapula of the Sugar Glider is smaller in size than that of the other two possums.The pelvic girdle Of the Common Brushtail Possum has a much wider ischium than those of the Common Brushtail Possum and the Sugar Glider. The ilium of the Sugar is much narrower and smaller than that of the other two possums Mammalian prey was found in 89%, insects in 13% and birds in 10% of the pellets. Of the mammals, Common Ringtail Possums occurred most frequently in the pellets over the year. There was no seasonal difference in the frequency of occurrence of Common Ringtail Possums and Sugar Gliders in pellets. However, Common Brushtail Possums were more likely to be taken in spring than in the other seasons. More adult Common Ringtail Possums were taken as prey than were other age classes over the year, except in summer when high numbers of young were consumed by the owls. The habitat of the Powerful Owl was examined by ground surveys and spotlight surveys in sixteen sites within the Warrandyte-Kinglake Nature Conservation Link. Four categories of survey sites were chosen with the following features. Category A - Sites with a dense understorey of shrubs and small trees, as well as many old trees (>10/ha) which might be suitable for nest hollows. Category B - Sites which lacked a dense understorey of shrubs and small trees and containing few or no old trees suitable for nest hollows. Category C - Sites with a dense understorey of shrubs and small trees but containing few or no old trees suitable for nest hollows. Category D - Sites which lacked a dense understorey of shrubs and small trees but having old trees (>10/ha) which might be suitable for nest hollows. High prey densities strongly correlated with the presence of hollows at these sites. In the light of the results, management recommendations were made for the future conservation of the Powerful Owls living at Christmas Hills. The following recommendations were particularly important: 1. Cleared or semi - cleared land within the Warrandyte Kinglake Nature Conservation Link be revegetated using indigenous species of eucalypts and waffles in order to provide a contiguous native forest corridor for the movement of possums and gliders between the Yarra River Valley and the Kinglake Plateau. 2. Continued planting of Eucalyptus spp. and Acacia spp. in the forested areas of the Warrandyte-Kinglake Nature Conservation Link. 3. Continued protection of healthy living trees to provide a continuous supply of hollow trees. 4. No falling of dead standing trees for firewood collecting as these can provide nest hollows for prey species of the Powerful Owl.

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