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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.
61

Study on the Integration of Conservation Measures for Chinese White Dolphin (Sousa chinensis) in Taiwan

Yip, Choi-pik 25 August 2011 (has links)
Following the global warming and climate change in the last twenty years, one of key actions on maintaining biodiversity is to save critical endangered species with aspect of intergrated management. Our study aims to explore integrated mechanism inside the case of Chinese White Dolphin conservation in Taiwan throught a qualitative research approach. The integrated mechanism was also understood under a concept of social-ecological system and analysed with a framework that was modified mitigation-adaptation model used to apply on climate change study. The capacity of management measures including of mitigation and adaptation was explored on three levels, i.e. animals, habitat, and society. Differences of the capacity in these three levels were compared between the cases in Taiwan and Hong Kong. The study also tried to point out possible responders who should conduct these conservation measures from a questionnaire survey. The statistical analysis revealed none of top measures must be under the responsibility of government in these three levels. The analysis showed that there is no correlation between the implementation of measures and the governmental responsibility. In addition, the top-six measures were mainly in the marine environment level and four of the measures had been implemented. In the analysis about governmental responsibility top-seven measures, should be under the responsibility of developers, instead of the government. Some suggestions were given at the end for integrated management of Chinese White Dolphin conservation in Taiwan.
62

Avoiding Earth Impacts Using Albedo Modification as Applied to 99942 Apophis

Margulieux, Richard Steven 2010 May 1900 (has links)
Current orbital solutions for 99942 Apophis predict a close approach to the Earth in April 2029. The parameters of that approach affect the future trajectory of Apophis, potentially leading to an impact in 2036, 2056, 2068, etc. The dynamic model used for this prediction does not account for non-gravitational perturbations including solar pressure and the Yarkovsky effect. Estimates of the displacement due to these perturbations range from -1500 to 1500km by 2029, comparable to 7? uncertainty in orbital solution. Uncertainties in physical characteristics stem from a lack of direct observations and a shortage of empirical data on similar objects. These perturbations, which stem from interactions with solar radiation, are directly related to the albedo of Apophis? surface. By modifying the average albedo of Apophis by 0.5%, between 4 and 15m of displacement can be effected between 2023 and 2029, rendering this method capable of avoiding all near-nominal solution keyholes. This modification is obtained by the deposition of electrostatically charged particles. These particles are charged via tribo-electrification and cure on the surface of Apophis creating a 30 micron thick layer of material with desired properties. This study found that a change in average albedo would nominally require 160kg of polytetrafluoroethylene (PTFE) to increase by 0.5% or 290kg of PTFE to decrease by 0.5%. The Apophis Exploration and Mitigation mission concept both improves accuracy of nongravitational perturbation models and delivers the albedo modification mechanism to Apophis, launching in 2021 and modifying albedo in 2023.
63

Use of Shark Shapes to Reduce Incidental Capture of Sea Turtles in the Long-Line Fisheries

Bostwick, Angela Sue 2010 August 1900 (has links)
An estimated 250,000 loggerhead (Caretta caretta) and leatherback (Dermochelys coriacea) sea turtles are taken each year as incidental catch by the pelagic long-line fishing industry. Various gear and bait modifications as well as time/area closures to fishing, enacted to reduce anthropogenic impacts on sea turtles, have been ineffective or incompatible with regional fishery interests. Chemosensory and auditory deterrents have yielded little benefit thus far in repelling sea turtles from long-lines. The fact that sea turtles are highly visual animals has precipitated studies of the efficacy of using shark shapes to repulse them from long-lines. Previous shark-shape studies yielded promising results, but their design lacked statistical rigor. The present study examined the response of 42 captive-reared loggerhead sea turtles (Caretta caretta) to a shark-shape model at the NOAA Sea Turtle Facility in Galveston, TX. To measure repulsive effect, time taken to consume squid bait beneath the shark model was compared to that for controls in which loggerheads were offered squid beneath a spherical object or a bare squid (i.e., no object control) in a captive setting. Additional responses compared among these three treatments were time spent near treatment, number of breaths taken, approaches to the treatment, and avoidance behaviors displayed (e.g., turning carapace toward treatment). Loggerheads exhibited anti-predator behavior toward the shark model, taking significantly more time to consume squid bait beneath the shark model than for the other two treatments. Turtles also spent significantly more time opposite the tank from the shark model, approached it less often, and exhibited more carapace turns to the model. Some avoidance of the spherical control object also was observed, but was not as pronounced as that displayed toward the shark model. While a repulsive effect of the shark model was resolved during the aforementioned trials, application of such models to reducing long-line fishery bycatch would require further research to identify a plausible application; numerous shapes attached to long-line hooks would be very cumbersome. However, it may be plausible to develop a “boy’s day kite” shark model that would unfurl and “fly” underwater, and could possibly be clipped to buoy float lines.
64

A tornado hazard analysis for Indiana and an evaluation of the emergency management needs of the Amish community

Lindsey, Amy M. January 2009 (has links)
Thesis (M.S.)--Ball State University, 2009. / Title from PDF t.p. (viewed on Dec. 14, 2009). Includes bibliographical references (p. 95-98).
65

An evaluation of vegetation and wildlife communities in mitigation and natural wetlands of West Virginia

Balcombe, Collins K. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xx, 417 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references.
66

Characterization of wetland soils in the Beaver Creek Watershed

Stephens, Kyle, January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains vi, 131 p. : ill. (some col.), col. map. Vita. Includes abstract. Includes bibliographical references (p. 69-74).
67

Technological evaluation of mineral sequestration of CO₂ by carbonation

Wei, Xinchao. January 2003 (has links)
Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains viii, 65 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 60-64).
68

The radioisotope unit radon analysis laboratory and its application toradon mitigation studies

Hung, Ling-chun., 孔令臻. January 1999 (has links)
published_or_final_version / Radioisotope / Master / Master of Philosophy
69

Documenting & Using Cognitive Complexity Mitigation Strategies (CCMS) to Improve the Efficiency of Cross-Context User Transfers

Bhagat, Rahul January 2011 (has links)
Cognitive complexity mitigation strategies are methods and approaches utilized by users to reduce the apparent complexity of problems thus making them easier to solve. These strategies often effective because they mitigate the limitations of human working memory and attention resources. Such cognitive complexity mitigation strategies are used throughout the design, development and operational processes of complex systems. Thus, a better understanding of these strategies, and methods that leverage them, can help improve the efficiency of such processes. Additionally, changes in the use of these strategies across various environments can identify cognitive differences in operating and developing across these contexts. This knowledge can help improve the effectiveness of cross-context user transfers by suggesting change management processes that incorporate the degree of cognitive difference across contexts. In order to document cognitive complexity mitigation strategies and the change in their usage, two application domains are studied. Firstly, cognitive complexity mitigation strategies used by designers during the engineering design process are found through an ethnographic immersion with a participating engineering firm, followed by an analysis of the designer's logbooks and validation interviews with the designers. Results include identification of five strategies used by the designers to mitigate design complexity. These strategies include Blackbox Modeling, Whitebox Modeling, Decomposition, Visualization and Prioritized Lists. The five complexity mitigation strategies are probed further across a larger sample of engineering designers and the usage frequency of these strategies is assessed across commonly performed engineering design activities which include the Selection, Configuration and Parametric activities. The results indicate the preferred use of certain strategies based on the engineering activity being performed. Such preferential usage of complexity mitigation strategies is also assessed with regards to Original and Redesign projects types. However, there is no indication of biased strategy usage across these two project characterizations. These results are an example of a usage-frequency based difference analysis; such analyses help identify the strategies that experience increased or reduced usage when transferring across activities. In contrast to the first application domain, which captures changes in how often strategies are used across contexts, the second application domain is a method of assessing differences based on how a specific strategy is used differently across contexts. This alternative method is developed through a project that aims to optimize the transfer of air traffic controllers across different airspace sectors. The method uses a previously researched complexity mitigation strategy, knows as a structure based abstraction, to develop a difference analysis tool called the Sector Abstraction Binder. This tool is used to perform cognitive difference analyses between air traffic control sectors by leveraging characteristic variations in how structure based abstractions are applied across different sectors. This Sector Abstraction Binder is applied to two high-level airspace sectors to demonstrate the utility of such a method.
70

Impact of recycled fiber on total carbon dioxide output during linerboard production /

Kuzma, Daniel J. January 2008 (has links)
Thesis (M.S.)--Youngstown State University, 2008. / Includes bibliographical references (leaves 47-50). Also available via the World Wide Web in PDF format.

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