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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.
121

Utilizing Remote Sensing and Geospatial Techniques to Determine Detection Probabilities of Large Mammals

Terletzky, Patricia A. 01 August 2013 (has links)
Whether a species is rare and requires protection or is overabundant and needs control, an accurate estimate of population size is essential for the development of conservation plans and management goals. Wildlife censuses in remote locations or over extensive areas are logistically difficult, frequently biased, and time consuming. My dissertation examined various techniques to determine the probability of detecting animals using remotely sensed imagery. We investigated four procedures that integrated unsupervised classification, texture characteristics, spectral enhancements, and image differencing to identify and count animals in remotely sensed imagery. The semi-automated processes had relatively high errors of over-counting (i.e., greater than 60%) in contrast to low (i.e. less than 19%) under-counting errors. The single-day image differencing had over-counting errors of 53% while the manual interpretation had over-counting errors of 19%. The probability of detection indicates the ability of a process or analyst to detect animals in an image or during an aerial wildlife survey and can adjust total counts to estimate the size of a population. The probabilities of detecting an animal in remotely sensed imagery with semi-automated techniques, single-day image differencing, or manual interpretation were high (e.g. ≥ 80%). Single-day image differencing resulted in the highest probability of detection suggesting this method could provide a new technique for managers to estimate animal populations, especially in open, grassland habitats. Remotely sensed imagery can be successfully used to identify and count animals in isolated or remote areas and improve management decisions. Sightability models, used to estimate population abundances, are derived from count data and the probability of detecting an animal during a census. Global positioning systems (GPS) radio-collared bison in the Henry Mountains of south-central Utah provided a unique opportunity to examine remotely sensed physiographic and survey characteristics for known occurrences of double-counted and missed animals. Bison status (detected, missed, or double-counted) was determined by intersecting helicopter survey paths with bison travel paths during annual helicopter surveys. The probability of detecting GPS-collared bison during the survey ranged from 91% in 2011 to 88% in 2012.
122

Use of Landsat Imagery and Geographical Information Systems in the Assessment of Rangeland Cover and Wildlife Habitat

Hunnicutt, Mary 01 January 1992 (has links)
The first chapter of this thesis reviews applications of satellite remote sensing and geographical information systems (GIS) in wildlife studies. The simpler uses of remote sensing are for habitat mapping, often using satellite imagery classified for other natural resources. More sophisticated applications incorporate remotely sensed data into a GIS for the digital manipulation of data planes. The most advanced applications are those which use remote sensing and GIS in models predicting habitat quality or population levels. The second chapter reports how brightness values of six Landsat Thematic Mapper (TM) bands were used in multiple linear regressions to predict percent cover of six rangeland components. Regression equations were applied to TM imagery to create cover maps for live shrub, dead and live shrub, sagebrush, forb/grass, forb, and bare ground/rock. Accuracy was assessed at two levels and ranged from 55 to 90%. The third chapter presents results of sage grouse surveys used with satellite data and GIS to assess habitat use patterns. Habitats used by grouse were compared to availability in the landscape for continuous images of rangeland cover variables, for discrete images of rangeland classes, and for habitat diversity values. Overall, results were comparable to those in studies using traditional methods.
123

Ecosystem Services Approach for Environment Decision Making Applications in the Mekong Delta, Vietnam / 生態系サービス概念の環境政策への適用: ベトナム国メコンデルタにおいて

Ho, Loc Huu 25 September 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20689号 / 工博第4386号 / 新制||工||1682(附属図書館) / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 清水 芳久, 教授 田中 宏明, 教授 米田 稔 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
124

OOPS! THEY BUILD IT AGAIN : A suitability analysis for future wind farm location in Sweden

Christofel, Aditya Billy January 2019 (has links)
The world energy needs increasing in a significant number and currently it is mainly sourced from the finite fossil fuel. Other than that, fossil fuel is the main source of CO2 emissions that leads to the increasing rate of global warming that will ultimately change the earth's climate. Thus, researcher began to look for alternative energy that is renewable and has the least impact to the world's climate; one example is wind energy. Sweden has experienced a significant increase in wind energy generation, where the wind production constantly grows in the double-digit rates since 2010. However, developing a wind energy requires a significant research and feasibility study in order to provide an economically sustainable operation. Wind farm needs to be located in areas with a good wind potential, however there are several technical and economic limitation on where the wind farm should be located. On top of that, social rejection might also hinder the development of wind energy. Audio-visual obstruction and disturbance to the natural state of the environment are the main arguments that were used to challenge the development of wind farm. Therefore, a multi-disciplinary study needs to be conducted in order to find the perfect balance; which is exactly what this study is all about. The result of this study shows that despite the threat of climate change, wind farm in Sweden could thrive due to the increasing wind speed across the country. It was also discovered that around 30% of the country is suitable, from the social, technical, and economic point of view, as a new location for wind farms. This study also reveals that most of the canceled / rejected wind farms were probably caused by the social rejection due to their proximity to population center or conservation areas. This study also discussed the concept of place attachment and identity that leads to the NIMBY attitude and reflects the concept of the social acceptance issue that happened in Sweden and on how to localize the wind farm concept to the local residence.
125

A Framework For The Assessment And Analysis Of Multi-hazardsinduced Risk Resulting From Space Vehicles Operations

Sala-Diakanda, Serge 01 January 2007 (has links)
With the foreseeable increase in traffic frequency to and from orbit, the safe operation of current and future space vehicles at designated spaceports has become a serious concern. Due to their high explosive energy potential, operating those launch vehicles presents a real risk to: (1) the spaceport infrastructure and personnel, (2) the communities surrounding the spaceport and (3) the flying aircrafts whose routes could be relatively close to spaceport launch and reentry routes. Several computer models aimed at modeling the effects of the different hazards generated by the breakup of such vehicles (e.g., fragmentation of debris, release of toxic gases, propagation of blast waves, etc.) have been developed, and are used to assist in Go-No Go launch decisions. They can simulate a total failure scenario of the vehicle and, estimate a number of casualties to be expected as a result of such failure. However, as all of these models - which can be very elaborate and complex - consider only one specific explosion hazard in their simulations, the decision of whether or not a launch should occur is currently based on the evaluation of several estimates of an expected number of casualties. As such, current practices ignore the complex, nonlinear interactions between the different hazards as well as the interdependencies between the estimates. In this study, we developed a new framework which makes use of information fusion theory, hazards' dispersion modeling and, geographical statistical analysis and visualization capabilities of geographical information systems to assess the risk generated by the operation of space launch vehicles. A new risk metric, which effectively addresses the lack of a common risk metric with current methods, is also proposed. A case study, based on a proposed spaceport in the state of Oklahoma showed that the estimates we generate through our framework consistently outperform estimates provided by any individual hazard, or by the independent combination of those hazards. Furthermore, the study revealed that using anything else than fusion could provide seriously misleading results, with potentially catastrophic consequences.
126

Interacting with command and control systems : Tools for operators and designers

Albinsson, Pär-Anders January 2004 (has links)
Command and control is central in all distributed tactical operations such as rescue operations and military operations. It takes place in a complex system of humans and artefacts, striving to reach common goals. The command and control complexity springs from several sources, including dynamism, uncertainty, risk, time pressure, feedback delays and interdependencies. Stemming from this complexity, the thesis approaches two important and related problem areas in command and control research. On a general level, the thesis seeks to approach the problems facing the command and control operators and the problems facing the designers in the associated systems development process. We investigate the specific problem of operators losing sight of the overall perspective when working with large maps in geographical information systems with limited screen area. To approach this problem, we propose high-precision input techniques that reduce the need for zooming and panning in touch-screen systems, and informative unit representations that make better use of the screen area available. The results from an experimental study show that the proposed input techniques are as fast and accurate as state-of-the-art techniques without the need to resort to zooming. Furthermore, results from a prototype design show that the proposed unit representation reduces on-screen clutter and makes use of off-screen units to better exploit the valuable screen area. Developing command and control systems is a complex task with several pitfalls, including getting stuck in exhaustive analyses and overrated reliance on rational methods. In this thesis, we employ a design-oriented research framework that acknowledges creative and pragmatic ingredients to handle the pitfalls. Our approach adopts the method of reconstruction and exploration of mission histories from distributed tactical operations as a means for command and control analysis. To support explorative analysis of mission histories within our framework, we propose tools for communication analysis and tools for managing metadata such as reflections, questions, hypotheses and expert comments. By using these tools together with real data from live tactical operations, we show that they can manage large amounts of data, preserve contextual data, support navigation within data, make original data easily accessible, and strengthen the link between metadata and supporting raw data. Furthermore, we show that by using these tools, multiple analysts, experts, and researchers can exchange comments on both data and metadata in a collaborative and explorative investigation of a complex scenario. / <p>Report code: LiU-Tek-Lic-2004:61.</p>
127

UNDERSTANDING AND CHANGING PHYSICAL ACTIVITY AMONG PEOPLE WITH SPINAL CORD INJURY: THE ROLE OF PSYCHOLOGICAL AND ENVIRONMENTAL FACTORS

ARBOUR, KELLY PATRICIA ANN 16 March 2015 (has links)
<p>The purpose of this dissertation was to use an integrative theoretical framework to examine the individual and environmental factors associated with leisure-time physical activity (LTPA) for persons living with spinal cord injury (SCI). Using a systematic approach, three studies were conducted to: (1) survey the accessibility and availability of physical activity facilities for Canadians living with mobility disabilities, (2) test an integrative, theoretical framework for understanding LTPA among people with SCI, and (3) implement a theory-based intervention that focuses on helping beginner exercisers living with SCI cope with salient individual and environmental LTPA barriers. </p> <p>Study 1 involved two sub-studies. Study lA used a modified version of the AIMFREE instrument (Rimmer et al., 2004) and provided evidence of the limited accessibility of fitness and recreational facilities (n=44) for persons with mobility disabilities. Study lB applied a geographical technique, Geographical Information Systems (GIS), to develop an objective proximity measure specific to persons with SCI. Results indicated a small, negative association between the objective presence of physical activity facilities and L TPA in a sample of persons with SCI (n=50), suggesting that living in close proximity to a facility which provides adaptive programming and equipment does not necessarily translate into greater LTPA for persons with SCI.</p> <p>As an extension of Study 1, Study 2 used structural equation modeling to conduct a cross-sectional examination of whether an environmental factor --neighbourhood perceptions--could enhance the Theory of Planned ehaviour's (TPB; Ajzen, 1985) ability to explain LTPA intentions and behaviour in persons with SCI (n=246). Results indicated a small, negative association between perceived wheeling infrastructure and LTPA intentions. However, perceptions of neighbourhood aesthetics and wheeling infrastructure did not explain significant variance in either L TPA intentions or behaviour, beyond that accounted for by the TPB constructs, suggesting that these eighbourhood factors do not enhance the TPB's ability to explain LTPA behaviour.</p> <p>Lastly, Study 3 used a randomized, controlled design to examine the effects of a 10-week action and coping planning intervention on enhancing LTPA and coping self efficacy in exercise intenders living with SCI (n=47). Results indicated greater LTPA for participants who formed action plans and coping plans (A+C condition) than for the participants who only formed action plans (A condition). Furthermore, the A+C condition had greater confidence to schedule their L TPA and overcome L TPA-related barriers than the A condition. These findings provide evidence of the benefits of supplementing action plans with coping plans for enhancing L TP A and coping self-efficacy beliefs among exercise intenders living with SCI. </p> <p>Together, these three studies provide a broader understanding of L TPA correlates and determinants in people with SCI, and provide evidence of the efficacy of multiple planning strategics for promoting L TPA in persons with SCI. The results provide an impetus for extending the scope of the research on the physical environment and LTPA towards persons with mobility disabilities. Moreover, the findings demonstrate the value of theory-based research for identifying the multidimensional correlates and determinants of LTPA, and for designing effective LTPA-enhancing interventions in persons with SCI. </p> / Thesis / Doctor of Philosophy (PhD)
128

A Method for Assessing Regional Bioenergy Potentials Based on GIS Data and a Dynamic Yield Simulation Model

Bao, Keyu, Padsala, Rushikesh, Coors, Volker, Thrän, Daniela, Schröter, Bastian 18 April 2023 (has links)
The assessment of regional bioenergy potentials from different types of natural land cover is an integral part of simulation tools that aim to assess local renewable energy systems. This work introduces a new workflow, which evaluates regional bioenergy potentials and its impact on water demand based on geographical information system (GIS)-based land use data, satellite maps on local crop types and soil types, and conversion factors from biomass to bioenergy. The actual annual biomass yield of crops is assessed through an automated process considering the factors of local climate, crop type, soil, and irrigation. The crop biomass yields are validated with historic statistical data, with deviation less than 7% in most cases. Additionally, the resulting bioenergy potentials yield between 10.7 and 12.0 GWh/ha compared with 13.3 GWh/ha from other studies. The potential contribution from bioenergy on the energy demand were investigated in the two case studies, representing the agricultural-dominant rural area in North Germany and suburban region in South Germany: Simulation of the future bioenergy potential for 2050 shows only smaller effects from climate change (less than 4%) and irrigation (below 3%), but the potential to cover up to 21% of the transport fuels demand in scenario supporting biodiesel and bioethanol for transportation.
129

Predicting Infestations of Hemlock Woolly Adelgid ( <em>Adelges tsugae</em> ) in Great Smoky Mountains National Park, Tennessee/North Carolina, USA

Snider, Scott January 2004 (has links)
No description available.
130

Kommunal samverkan inom GIS : En undersökning av Västerbottens och Norrbottens kommuner

Ekeståhl Unger, Clara-Elin January 2024 (has links)
The aim of this paper is to examine GIS in municipalities within Norrbotten and Västerbotten. This involves examining the GIS use in the municipalities. It also involves an investigation of how cooperation between the municipalities works and could develop in the future. This study is based on the NorrGIS inventory of GIS from 2021. This paper is based on a quantitative research method with a questionnaire that has been sent out to representatives within the GIS operations in the municipalities. Competence and resources within GIS are limited within the municipalities which may be based on size and resource assets. GIS use differs between municipalities and many of the GIS operations within the municipalities need to be improved. A major problem is that the competence within the municipalities is not sufficient. There is also cooperation within GIS tools and many of the municipalities have GeoSecma as the main tool. Furthermore, GIS collaboration is needed to use GIS full potential. A collaboration may be a necessity for smaller municipalities to overcome obstacles that GIS use entails. A large part of the obstacles for GIS lies at the political level, which can be a difficult challenge to manage. Human resources and technical resources are considered affordable, the problem lies in how decision-makers choose to allocate resources. The political level places limitations on possible cooperation. Despite limitations in both political ambition and competence, the result displays a need for collaboration within the municipalities. Another problem is the responsibility for cooperation. Who has the final responsibility for GIS-collaboration to function optimally?

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