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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.
571

Assessing Avian Responses to Habitat Management Along Pipeline Right-of-ways in Eastern Ohio

Lolya, Lewis Matthew 23 October 2019 (has links)
No description available.
572

Estimates of Waste Rice, Natural Seeds, and Wetland Birds in Gulf Coast Prairie Ricelands

Marty, Joseph Roy 06 May 2017 (has links)
Hundreds of wetland bird species use ricelands annually in the Gulf Coast Prairie region of Louisiana and Texas. Much of the original ecosystem was transformed for rice and other crops, cattle ranching, flood control, and other human uses. Flooded production and idled ricelands provide critical foraging habitat for breeding, migrating, and wintering wetland birds. Ricelands in coastal Louisiana and Texas provide approximately 42% of the estimated habitat carrying capacity for wintering waterfowl in this region. In 2010, the Deepwater Horizon oil spill in the Gulf of Mexico prompted enactment of the Migratory Bird Habitat Initiative (MBHI) by USDA Natural Resources Conservation Service. The MBHI provided avian habitat, including flooded ricelands, inland from oil impacted areas. My objectives were to: 1) estimate and model variation in biomass of waste rice and natural seeds as potential waterfowl forage in Gulf Coast Prairie ricelands, 2) estimate and model variation in wetland bird use of ricelands, and 3) conduct sensitivity analyses of bioenergetics models by varying foraging thresholds and true metabolizable energy (TME) values. A growing season of ~270 days allows Gulf Coast rice producers to grow two rice crops (i.e., the second termed ratoon). Waste rice was greatest in production fields with harvested and standing ratoon crops, and natural seed biomass was greatest in idled fields with standing vegetation. Wetland bird species richness and waterbird abundance were greatest in shallowly flooded (1–15 cm) ricelands with sparse vertical vegetation (1–20 cm), and duck abundance was greatest in shallow–intermediately (1–30 cm) flooded ricelands with short vegetation (1–15 cm). Shallowly flooded rice fields containing harvested or standing ratoon crops, and shallowly flooded idled fields with standing vegetation provided abundant potential foods for waterfowl and waterbirds. Bioenergetics models indicated that planners in the Gulf Coast Prairie region may be underestimating riceland habitat requirements for waterfowl by 10,000 ha. Models were most sensitive to changes in seed biomass estimates, and less sensitive to changes in foraging thresholds and TME values. Collectively, these results will facilitate conservation partners to refine models for conserving habitats for waterfowl and other waterbirds in the Gulf Coast Prairie.
573

Seed and Waterbird Abundances in Ricelands in the Gulf Coast Prairies of Louisiana and Texas

Marty, Joseph Roy 14 December 2013 (has links)
Rice not collected by harvesters and natural seeds are important foods for waterfowl. Estimation of abundance of these seeds is necessary for calculating waterfowl habitat conservation needs in the Louisiana Chenier Plain (LCP) and Texas Mid-Coast (TMC). My objectives were to quantify dry mass of rice and other seeds from August-November 2010, and estimate waterbird abundances on farmed and idle ricelands in these regions from December 2010-March 2011. Rice abundance in farmed ricelands ranged from 159.7 kg/ha (CV = 66.6%) to 1,014.0 kg/ha (CV = 8.3%). Natural seed abundance in idle ricelands ranged from 99.7 kg/ha (CV = 32.9%) to 957.4 kg/ha (CV = 17.2%). Greatest waterbird densities occurred in shallowly flooded (i.e., ¡Ü30 cm) disked ricelands (mean = 7.35 waterbirds/ha, 90%; CI = 2.37-19.70). Ratoon, disked, and shallowly flooded ricelands are important habitat for non-breeding waterbirds but variable estimates of seed and waterbird abundances warrant continuation of this study.
574

Characterization and classification of Bicknell's Thrush (Catharus bicknelli) habitat in the Estrie region, Québec

Connolly, Véronique. January 2000 (has links)
No description available.
575

3D-Reconstruction of the Common Murre / 3D-Rekonstruering av Sillgrissla

Hägerlind, Johannes January 2023 (has links)
Automatic 3D reconstruction of birds can aid researchers in studying their behavior. Recently there has been an attempt to reconstruct a variety of birds from single-view images. However, the common murre's appearance is different from the birds that have been studied. Moreover, recent studies have focused on side views. This thesis studies the 3D reconstruction of the common murre from single-view top-view images. A template mesh is first optimized to fit a 3D scan. Then the result is used to optimize a species-specific mean from side-view images annotated with keypoints and silhouettes. The resulting mean mesh is used to initialize the optimization for top-down images. Using a mask loss, a pose prior loss, and a bone length loss that uses a mean vector from the side-view images improves the 3D reconstruction as rated by humans. Furthermore, the intersection over union (IoU) and percentage of correct keypoint (PCK), although used by other authors, are insufficient in a single-view top-view setting.
576

Making Sense of Material Culture : A Sensory Approach to Bird-Shaped Vessels in Imperial Age Greece

Enevång Viklund, Lina January 2023 (has links)
The focus of this thesis is Roman bird-shaped glass vessels from the 1 st and 2 nd centuries AD. The vessels were containers for cosmetics and distinguished themselves from other types of unguentaria in that once they had been filled with cosmetic powder, the vessels were reheated and sealed shut by fire. The only way to extract the content was to break the tip of the bird’s tail; only then could the powder be sprinkled out. While ancient glass is a well-established field of research, studies concerning bird-shaped vessels are scarce. The present study, situated in Roman age Greece, is concerned with the sensory experiences that these objects evoked in their users and attempts to reflect the ancient lived experience of the vessels. In order to speculate on possible sensory stimuli, contextual aspects concerning where, why, and by whom these vessels were used are explored. Based on these contextual aspects, the bird-shaped vessels are studied in hypothetical scenarios where potential multisensory experiences are explored.
577

Negotiating Identity: Culturally Situated Epideictic in the Victorian Travel Narratives of Isabella Bird

Robinson, Katherine Reilly 17 November 2009 (has links) (PDF)
Epideictic rhetoric, one of the classical modes of persuasion described by Aristotle, has faced some criticism concerning its value in the realm of rhetoric. Though attitudes have been shifting over the last several decades, there is still a tendency to undervalue epideictic, falling back on the Aristotelian system of ceremonial oratory. However, its “praise and blame” style of persuasion employs of the type of rhetor / audience identification described by Kenneth Burke. Epideictic rhetoric is a major component of virtually any communication, as the speaker or writer seeks to create a bond with that audience so as to persuade them of something. This is evident in Victorian women's travel narratives; not necessarily noted for rhetoricality, they are nonetheless powerfully rhetorical in their prose as they foster emotionally- based identifications. Through their employment of epideictic description, travel narratives are not merely showpieces, but rather catalysts for social consciousness and change. As we move from the civic discourse-based Aristotelian classification of epideictic to encompass literary works like the travel narrative, the multifaceted value of epideictic is undeniable.
578

Knightly Bird Vows: A Case Study in Late Medieval Courtly Culture

Boyce, Liel Y. 14 March 2012 (has links) (PDF)
In the late Middle Ages, there was a series of instances wherein knights vowed upon birds. Two of these, the first and the last, are historical events: The Feast of the Swans with Edward I in England on 22 May 1306 and the Feast of the Pheasant with Philip the Good in the duchy of Burgundy on 17 February 1454. Edward I held the Feast of the Swans as part of his son's dubbing ceremony, including the entire court taking vows on two swans. The Feast of the Pheasant was an elaborate banquet that Philip the Good used to gather support for a crusade. The other three are literary texts: the Voeux du paon, the Voeux de l’épervier, and the Voeux du héron. The Voeux du Paon contains an account of a group of nobility connected to Alexander the Great at a truce banquet. One of the prisoners accidentally kills a lady's peacock and the group decides to take vows on it before recommencing battle. The Voeux de l’épervier concerns Henry VII of Luxembourg en route to Italy to claim the title of Holy Roman Emperor. One of his knights accidentally kills a sparrowhawk and they decide, as a court, to take vows on it. Lastly, the Voeux du héron depicts Robert d' Artois inciting Edward III to initiate the Hundred Years' War over a heron. Each of these instances creates a sub-set, the bird vow cycle, within medieval vowing tradition. The origin of the bird vow cycle lies within that vowing tradition. John L. Grigsby has declared these instances as a crystallization of the gab convention of medieval literature. However, Grigsby ignored the Feast of the Swans and the Feast of the Pheasant since he was concentrated on defining a literary genre. This thesis attempts to show the bird vow cycle as connected this this literary tradition, but also a crystallization of the courtly culture that had developped in the late Middle Ages. It also attempts to show the origins of this cycle—it not only came out of a vowing tradition, but also is tied to King Arthur traditions. The culture of the late Middle Ages was nostalgic and looking back towards an idealistic version of the past—whether in legends like Arthur or historical figures like Alexander. Thus, the knightly bird vow cycle was a particular example of that fantasy in their culture. In conclusion, this thesis not only gathers together what literature there is on the knightly bird vow cycle, but it places it within a literary and historical context. The knightly bird vow cycle would not have been possible without a culture obsessed with fantasy and idealistic courtly culture.
579

A Parametric Study of Formation Flight of a Wing Based on Prandtl's Bell-Shaped Lift Distribution

Lukacovic, Kyle S 01 June 2020 (has links) (PDF)
The bell-shaped lift distribution (BSLD) wing design methodology advanced by Ludwig Prandtl in 1932 was proposed as providing the minimum induced drag. This study used this method as the basis to analyze its characteristics in two wing formation flight. Of specific interest are the potential efficiency savings and the optimal positioning for formation flight. Additional comparison is made between BSLD wings and bird flight in formation. This study utilized Computational Flow Dynamics (CFD) simulations on a geometric modeling of a BSLD wing, the Prandtl-D glider. The results were validated by modified equations published by Prandtl, by CFD modeling published by others, and by Trefftz plane analysis. For verification, the results were compared to formation flight research literature on aircraft and birds, as well as published research on non-formation BSLD flight. The significance of this research is two part. One is that the BSLD method has the potential for significant efficiency in formation flight. The optimal position for a trailing wing was determined to be partially overlapping the leading wing vortex core. For a BSLD wing these vortices are located inboard from the wingtips resulting in wingtip overlap and have a wider impact downstream than the elliptical lift distribution (ELD) wingtip vortices. A second aspect is that avian research has traditionally been studied assuming the ELD model for bird flight, whereas this study proposes that bird flight would be better informed using the BSLD.
580

Combining Multiband Remote Sensing and Hierarchical Distance Sampling to Establish Drivers of Bird Abundance

Richter, Ronny, Heim, Arend, Heim, Wieland, Kamp, Johannes, Vohland, Michael 11 April 2023 (has links)
Information on habitat preferences is critical for the successful conservation of endangered species. For many species, especially those living in remote areas, we currently lack this information. Time and financial resources to analyze habitat use are limited. We aimed to develop a method to describe habitat preferences based on a combination of bird surveys with remotely sensed fine-scale land cover maps. We created a blended multiband remote sensing product from SPOT 6 and Landsat 8 data with a high spatial resolution. We surveyed populations of three bird species (Yellow-breasted Bunting Emberiza aureola, Ochre-rumped Bunting Emberiza yessoensis, and Black-faced Bunting Emberiza spodocephala) at a study site in the Russian Far East using hierarchical distance sampling, a survey method that allows to correct for varying detection probability. Combining the bird survey data and land cover variables from the remote sensing product allowed us to model population density as a function of environmental variables. We found that even small-scale land cover characteristics were predictable using remote sensing data with sufficient accuracy. The overall classification accuracy with pansharpened SPOT 6 data alone amounted to 71.3%. Higher accuracies were reached via the additional integration of SWIR bands (overall accuracy = 73.21%), especially for complex small-scale land cover types such as shrubby areas. This helped to reach a high accuracy in the habitat models. Abundances of the three studied bird species were closely linked to the proportion of wetland, willow shrubs, and habitat heterogeneity. Habitat requirements and population sizes of species of interest are valuable information for stakeholders and decision-makers to maximize the potential success of habitat management measures.

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