• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 175
  • 23
  • 22
  • 8
  • 7
  • 7
  • 6
  • 5
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • Tagged with
  • 344
  • 95
  • 45
  • 40
  • 40
  • 38
  • 36
  • 32
  • 31
  • 30
  • 30
  • 27
  • 26
  • 25
  • 23
  • 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.
231

Unusual-Object Detection in Color Video for Wilderness Search and Rescue

Thornton, Daniel Richard 20 August 2010 (has links) (PDF)
Aircraft-mounted cameras have potential to greatly increase the effectiveness of wilderness search and rescue efforts by collecting photographs or video of the search area. The more data that is collected, the more difficult it becomes to process it by visual inspection alone. This work presents a method for automatically detecting unusual objects in aerial video to assist people in locating signs of missing persons in wilderness areas. The detector presented here makes use of anomaly detection methods originally designed for hyperspectral imagery. Multiple anomaly detection methods are considered, implemented, and evaluated. These anomalies are then aggregated into spatiotemporal objects by using the video's inherent spatial and temporal redundancy. The results are therefore summarized into a list of unusual objects to enhance the search technician's video review interface. In the user study reported here, unusual objects found by the detector were overlaid on the video during review. This increased participants' ability to find relevant objects in a simulated search without significantly affecting the rate of false detection. Other effects and possible ways to improve the user interface are also discussed.
232

Variability of Carbon Stock in Florida Flatwoods Ecosystems Undergoing Restoration and Management

Becker, Kathryn Elizabeth 01 January 2011 (has links)
The global community is struggling with mitigating the effects of widespread habitat loss and degradation; the effects of which are being further magnified in the face of global climate change. Quality natural habitat is becoming increasingly limited and atmospheric carbon levels continue to rise. Therefore, land managers responsible for multiuse management are often faced with the dilemma of managing ecosystems for biodiversity, as well as optimizing ecosystem services such as carbon storage and sequestration. However, some management techniques used to meet these objectives may yield conflicting results, specifically, the management tool of prescribed fire. Fire is crucial in maintaining species composition and structure in many ecosystems, but also results in high carbon emissions. Thus, it is important for land mangers to achieve the most efficient prescribed fire management regime to both preserve plant and animal communities, and optimize carbon storage. A former ranchland at the Disney Wilderness Preserve, Central Florida, USA is being restored to native ecosystems and managed to preserve biodiversity and increase carbon storage. This study quantified the carbon stocks within the aboveground biomass, litter, and top 90 cm of soil in five ecosystems at the Disney Wilderness Preserve, all of which are managed with prescribed fire every two to three years. These carbon stocks were compared in ecosystems in different stages of restoration: bahia grass pasture, pasture in restoration for longleaf pine flatwoods, and restored longleaf pine flatwoods. The carbon stocks were also compared among three restored flatwoods communities: longleaf pine flatwoods, slash pine flatwoods, and scrubby flatwoods. To determine the effects of the current prescribed fire management, carbon stocks were quantified and compared in recently burned areas (burned 4 months prior) and areas burned two to three years prior, in all ecosystems. Soil carbon properties were assessed using ¹³C isotope analysis. Aboveground biomass and litter carbon stocks were found to increase with higher stage of restoration, and were significantly less in areas with recent fire management. The results of this study did not provide evidence that soil carbon stock was significantly different in different stages of restoration or at different times since fire, but soil carbon stock was found to be significantly different among the flatwoods communities. In un-restored pasture and pasture in restoration sites, the soil was found to be increasingly depleted in ¹³C with increasing soil depth. This pattern indicated that carbon in the upper, more labile soil carbon pool had been derived from current C4 pasture or native grasses, while carbon in the deeper, more stable carbon pool is a legacy of the historical C3 forest vegetation that existed prior to conversion to pasture. Additionally, a pattern of less depletion in ¹³C with increasing time since deforestation was noted, indicating an increasing loss of historic forest carbon with increasing pasture age. As the pastures in restoration for longleaf pine flatwoods mature, the isotopic composition of the soil profile in the restored longleaf pine flatwoods may serve as a reference value for the soil profiles of these sites. Overall, the mean carbon stock in the aboveground biomass, litter and top 90 cm of soil in the un-restored pasture was ~13.3 kg C/m², the carbon stock in the pasture in restoration was ~12.7 kg C/m², the longleaf pine flatwoods had the highest carbon stock at ~17.7 kg C/m², the scrubby flatwoods had the smallest carbon stock at ~7.7 kg C/m², and the slash pine flatwoods had a carbon stock of ~15.8 kg C/m².
233

Vägar genom vildmarken: Nation, nationalism och synen på vildmarken i STF:s årsskrift 1900-1910

Jönsson, Jimmy January 2010 (has links)
I den här uppsatsen undersöks vilka nationella värden som tillskrevs naturlandskapet vildmarken i Svenska Turistföreningens årsskrift från 1900-1910. Uppsatsens syfte är att synliggöra hur representationen av landskapet i årsskriften förändrades i samband med en förändring av den nationalistiska diskursen. Undersökningen genomförs med diskursanalytiska metoder, och utifrån perspektivet nation.Vildmarken tillskrivs värden som ”skön”, ”poetisk”, ”vild”, ”öde”, ”orörd” och ”gammal”. Undersökningen visar att vildmarken värderas utifrån dess motsats, nämligen människor, kultur, civilisation och bebyggelse, samtidigt som den beskrivs bli allt mer publik och attraktiv för en större mängd människor. Vidare visar undersökningen att vildmarken framställs som det främsta av Sveriges naturlandskap, och de värden som tillskrivs den ses som nationella värden. / This essay study the influence of national attributes on description of nature landscape, the wilderness, in the Yearbook of the Swedish Tourist Association 1900-1910 (Svenska Turistföreningens årsskrift). The main objective of the essay is to explore how the representation of the landscape changed in the empirics, accordance with the changes in the nationalistic discourse. The study is based on discourse analytical methods, and focuses on the perspective nation.The wilderness is ascribed values like “beautiful”, “poetic”, “wild”, “desolated”, “untouched” and “old”. The study shows that the wilderness is considered and valued in relation to its opposite, which is being identified as human beings, culture, civilisation and endowed areas. Simultaneously it is described as more public and an increasing attraction to a larger crowd of people. The wilderness is also interpreted as a nature landscape constructed as the foremost in all of Sweden, and the ascribed attributes are seen as national attributes.
234

So . . . We're Going for a Walk: A Placed-Based Outdoor Art Experiential Learning Experience

Stewart, Priscilla Anne 01 August 2019 (has links)
Schools in the United States often emphasize making children competitive in a global economy while neglecting the importance of developing citizens who are ecologically responsible. Problems of climate change, loss of biodiversity, mass extinctions and degradation of the natural environment, are often ignored. Some researchers have suggested that children lack unstructured play time in nature, have an increased amount of screen time, lack mindfulness, and are insulated from the natural world. Many children rarely have significant experience with nature's wildness. It is common for people to experience a sense of placelessness in the hyper-mobility of present times where "globalizing" agendas limit a sense of place or community. Teachers can also feel constrained by the physical confines of school and the intellectual confines of ordinary school curriculum. As a response to my students' lack of significant experiences with nature, my own dissatisfaction with ordinary teaching, and my sense that school curricula neglect ecological issues and restricts teaching innovation, I created a summer mountain wilderness art workshop designed to give 6th, 7th and 8th grade students an immersive alternative art education experience. This study explored the affordances and limitations of an alternative classroom focused on outdoor experiences, walking, art/ecological studies, and my own experiences in attempting to change the conditions of teaching and learning. This research uses qualitative methodologies including action-based research, elements of a/r/tography, arts-based research, and an ecological arts-based inquiry that involves questions about ecology, community, and artistic heritage.
235

‘Because It Was Hardcore and It Was Cool’: Masculinity as the Basis of Consent in Geochemical Sampling

Claus, Russell 06 1900 (has links)
Geochemical samplers carry out manual labour in difficult and dangerous conditions while largely unsupervised. This paper explores questions regarding the labour effort provided by these workers which often goes above and beyond the level necessary to maintain employment and at times endangers their personal safety. This extra effort is provided despite relatively high levels of worker autonomy, low levels of supervision, and little apparent economic incentive. Analysis of worker-level interviews using a number of possible theoretical frameworks indicates that more coercive factors such as direct managerial control and employment insecurity are unable to fully explain sampler behaviour and, instead, participant accounts indicate a form of active worker consent to increased labour effort and risk taking. This is a gendered worker consent based on a form of contingent upon the specific context of geochemical sampling. These specific contingent factors are: a working class masculinity derived from the hard manual labour of the work; the wilderness context that facilitates tropes of ‘man versus nature’ reinforcing the masculine workplace culture and obscuring the appropriation of surplus by more easily allowing the workplace to be interpreted as non-capitalist; and a fraternal masculinity resulting from the crew-based workplace organization and highly male dominated workforce composition, intensified by the conforming pressure of isolated camp life. This specific masculinity forms a basis of consent by which the autonomy afforded to workers by the labour process of geochemical sampling helps rather than hinders the imperative of management to encourage workers to exert the maximum effort. / Thesis / Master of Arts (MA)
236

Visitor Awareness of Low-impact Camping Techniques in the Wilderness Area Isle Royale National Park, Michigan: An Investigation of Possible Affecting Factors

Milanowski, Shannon M. 15 November 2002 (has links)
No description available.
237

Qualitative Examination of the Group Development Process Within an Adventure Programming Context

Dexel, Levi A. 10 August 2009 (has links)
No description available.
238

Controlling the Great Common: Hydrography, the Marine Environment, and the Culture of Nautical Charts in the United States Navy, 1838-1903

Smith, Jason W. January 2012 (has links)
This dissertation uses hydrography as a lens to examine the way the United States Navy has understood, used, and defined the sea during the nineteenth century. It argues, broadly, that naval officers and the charts and texts they produced framed the sea as a commercial space for much of the nineteenth century, proceeding from a scientific ethos that held that the sea could be known, ordered, represented, and that it obeyed certain natural laws and rules. This was a powerful alternative to existing maritime understandings, in which mariners combined navigational science with folkloric ideas about how the sea worked. Hydrography proved an important aspect of the American maritime commercial predominance in the decades before the Civil War. By the end of the century, however, new strategic ideas, technologies, and the imperatives of empire caused naval officers and hydrographers to think about the sea in new ways. After the Spanish-American War of 1898, the Navy pursued hydrography with increased urgency, faced with defending the waters of a vast new oceanic empire. Surveys, charts, and the language of hydrography became central to the Navy's war planning and war gaming, to the strategic debate over where to establish naval bases, and, ultimately, it figured significantly in determining the geography of the American empire. Throughout, however, the sea continued to be a dynamic, powerful force in itself that flouted hydrographers' and naval officers' attempts to represent and control it. Charts and the cartographic process that produced them are full of meaning. By placing hydrography and the sea environment at the center of the narrative, historians can better understand the role of science, knowledge, and cartographic representations in expanding American commercial and naval power over the ocean. / History
239

Reintegrating Darkness: An Exploration into Lived Experiences of Natural Darkness

Frey, Sean 08 September 2022 (has links)
Background: With current environmental issues of light pollution as a point of departure, this thesis draws a link between Western society’s subjugation of darkness within personal and collective psyches, and the harmful impacts caused by the decline of Natural Darkness (ND) at night, via the use of artificial light. Purpose of Research: Global and societal issues related to light pollution, viewed through a Jungian ecopsychological framework, led to the exploration of reintegrating ND within the human psyche through outdoor, overnight therapeutic practices in wilderness settings. Methods Used: Semi-structured interviews were conducted via Zoom with eight participants who described their memories with ND during overnight therapeutic wilderness experiences. Findings: Participants assigned ND with characteristics including spaciousness, magical, enveloping, and being cocoon-like; and described experiences of reduced boundaries, increased fear, feelings of interconnection, as well as greater connection to the spiritual realm and to unprocessed psychological material. Conclusion: Findings suggest that, for this sample, ND provided conditions for rest, spiritual connection and the processing of psychological material. / Graduate
240

Spatial Studies to Support the Management of Long Distance Trails

Meadema, Peter Fletcher 24 February 2023 (has links)
Trails are essential transportation infrastructure supporting access to protected natural areas and providing recreation to hikers, runners, cyclists, equestrians, motorists, and many more worldwide. This research presents spatial studies intended to improve understanding of the environmental, managerial, and use-related factors that influence management of and physical and experiential conditions on long-distance hiking trails. The first study investigates a dataset from the Appalachian Trail (AT) to examine methods for using high resolution digital elevation models to measure terrain steepness near trails and along trails or potential trail routes. This analysis supports trail planning and assessment efforts because these terrain metrics strongly influence physical trail sustainability and are useful to evaluate the difficulty of travel along trails. The second study analyzes long-distance use patterns on the Pacific Crest Trail (PCT) as depicted by a computer model developed from a survey administered to long-distance hikers, trail counters, observations, and registers. In addition to describing use patterns, the process is intended to inform the selection of methods for visitor use monitoring in response to the complexity and level of controversy of management needs. The third study examines the spatial relationships between the PCT, a national scenic trail, and other congressionally designated land areas including wilderness, wild and scenic rivers, and national monuments and how this complexity is manifested in camping management strategies and impacts along the trail corridor. This analysis supports managing for the multiple congressional mandates across the PCT landscape and improves understanding and management of interagency transboundary travel on the trail. / Doctor of Philosophy / Trails are essential transportation infrastructure supporting access to protected natural areas and providing recreation to hikers, runners, cyclists, equestrians, motorists, and many more worldwide. This research presents spatial studies intended to improve understanding of the environmental, managerial, and use-related factors that influence management and physical and experiential conditions on long-distance hiking trails. The first study investigates a dataset from the Appalachian Trail (AT) to examine methods for using high resolution digital elevation models to measure terrain steepness near trails and along trails or potential trail routes to improve digital trail assessment and planning. The second study analyzes long-distance use patterns on the PCT as depicted by a computer model developed from a survey administered to long-distance hikers, trail counters, observations, and registers. The third study examines the complexity of managing transboundary long distance trails by quantifying the spatial relationships between the Pacific Crest Trail (PCT), a national scenic trail, and other congressionally designated land areas, and by reviewing camping impacts at high use locations on the trail corridor.

Page generated in 0.0965 seconds