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• 11. [Article] Multi-spatial scale representation of landscape transitions using landsat thematic mapper data and scale-space filters

  This thesis considered current approaches to describing landscape pattern, identified scale issues associated with defining objects, and explored techniques to reliably group elements based on land cover ...

  Citation × Citation Citation Abstract Copy Title: Multi-spatial scale representation of landscape transitions using landsat thematic mapper data and scale-space filters Author: Lindeman, Dale R. This thesis considered current approaches to describing landscape pattern, identified scale issues associated with defining objects, and explored techniques to reliably group elements based on land cover as represented by satellite imagery. It was recognized that there is an important need to develop tools that can be applied using remotely sensed data to objectively identify landscape features at multiple spatial scales. The thesis focused on the potential for the use of specific digital image processing techniques to objectively generate multi-scale landscape heterogeneity models from Landsat Thematic Mapper (TM) satellite imagery. An approach using Difference-of-Gaussian (DoG) scale-space filters was used to process TM satellite data, transformed into the Normalized Difference Vegetation Index (NDVI), to define discrete landscape units across a range of scales. A series of Difference-of-Gaussian filters, with standard deviation (a) pairs of 0.9 and 1.1, 0.8 and 1.2, and 0.7 and 1.3, was applied to TM data. Results were compared against published ecoregion classifications and aerial orthophotography. These comparisons showed that the applied filters failed to accurately define landscape elements at a range of spatial scales. Filter size was found to be highly sensitive to the resolution of the image and object boundaries were maldelineated when complex boundary combinations were encountered. A modified approach using Gaussian/Difference-of-Gaussian or GaussianlLaplacian filter combinations and an alternate approach of watershed segmentation were recommended as potential techniques to test in further study. Future study should also include statistical approaches to aggregate zones and relate delineated zones to an actual, on-the-ground physiognomic classification scheme. Title: Multi-spatial scale representation of landscape transitions using landsat thematic mapper data and scale-space filters Author: Lindeman, Dale R. This thesis considered current approaches to describing landscape pattern, identified scale issues associated with defining objects, and explored techniques to reliably group elements based on land cover as represented by satellite imagery. It was recognized that there is an important need to develop tools that can be applied using remotely sensed data to objectively identify landscape features at multiple spatial scales. The thesis focused on the potential for the use of specific digital image processing techniques to objectively generate multi-scale landscape heterogeneity models from Landsat Thematic Mapper (TM) satellite imagery. An approach using Difference-of-Gaussian (DoG) scale-space filters was used to process TM satellite data, transformed into the Normalized Difference Vegetation Index (NDVI), to define discrete landscape units across a range of scales. A series of Difference-of-Gaussian filters, with standard deviation (a) pairs of 0.9 and 1.1, 0.8 and 1.2, and 0.7 and 1.3, was applied to TM data. Results were compared against published ecoregion classifications and aerial orthophotography. These comparisons showed that the applied filters failed to accurately define landscape elements at a range of spatial scales. Filter size was found to be highly sensitive to the resolution of the image and object boundaries were maldelineated when complex boundary combinations were encountered. A modified approach using Gaussian/Difference-of-Gaussian or GaussianlLaplacian filter combinations and an alternate approach of watershed segmentation were recommended as potential techniques to test in further study. Future study should also include statistical approaches to aggregate zones and relate delineated zones to an actual, on-the-ground physiognomic classification scheme. Close

• 12. [Article] Distribution and prediction of Swiss needle cast of Douglas-fir in coastal Oregon

  This study was directed to improve our understanding of the ecology of Swiss needle cast (SNC) of Douglas-fir, a disease that produces extensive damage to forests and plantation in the coastal region of ...

  Citation × Citation Citation Abstract Copy Title: Distribution and prediction of Swiss needle cast of Douglas-fir in coastal Oregon Author: Rosso, Pablo H. This study was directed to improve our understanding of the ecology of Swiss needle cast (SNC) of Douglas-fir, a disease that produces extensive damage to forests and plantation in the coastal region of Oregon and Washington. A disease prediction model for the coastal area of Oregon was built by establishing the relationship between the distribution of disease severity and the environment. Currently available methods of determining the distribution of SNC were analyzed, and the possibility of mapping the disease using Landsat TM satellite images was explored. Two types of regression approaches were used to study the relationship between disease severity and climate, topography, soil and forest stand characteristics. Although both types provided useful information and insight, the multiple regression approach was chosen over the regression tree analysis to build the model, due to its capacity to produce a continuous prediction response. Fog occurrence, precipitation, temperature, elevation and slope aspect, were the variables that contributed to explain most of the disease severity variability. Findings agree with and formalize our previous understanding of the ecology of SNC: cool and wet conditions in summer appear to increase disease severity. When the model was applied to past climate conditions, retrospective predictions suggest that changes in climate in the last two decades could help to explain the observed recent regional increase in SNC disease severity. The resulting model was used to construct a disease prediction map. This map showed an accuracy equivalent to the currently available SNC aerial survey. The prediction model, however, is able to produce a continuous prediction surface, more suitable for testing and appropriate for assisting in disease management and research. A strong relationship between mature stand canopy defoliation and the Landsat TM indices greenness and brightness, indicates that it is possible to use satellite imagery to map SNC. In contrast, young stands showed high variability, most likely due to the relatively high proportion of exposed understory vegetation. The possibility of mapping stand defoliation is of great importance because this symptom can be directly linked to tree growth and forest productivity. Satellite imagery can be used in future and in retrospective disease mapping. Title: Distribution and prediction of Swiss needle cast of Douglas-fir in coastal Oregon Author: Rosso, Pablo H. This study was directed to improve our understanding of the ecology of Swiss needle cast (SNC) of Douglas-fir, a disease that produces extensive damage to forests and plantation in the coastal region of Oregon and Washington. A disease prediction model for the coastal area of Oregon was built by establishing the relationship between the distribution of disease severity and the environment. Currently available methods of determining the distribution of SNC were analyzed, and the possibility of mapping the disease using Landsat TM satellite images was explored. Two types of regression approaches were used to study the relationship between disease severity and climate, topography, soil and forest stand characteristics. Although both types provided useful information and insight, the multiple regression approach was chosen over the regression tree analysis to build the model, due to its capacity to produce a continuous prediction response. Fog occurrence, precipitation, temperature, elevation and slope aspect, were the variables that contributed to explain most of the disease severity variability. Findings agree with and formalize our previous understanding of the ecology of SNC: cool and wet conditions in summer appear to increase disease severity. When the model was applied to past climate conditions, retrospective predictions suggest that changes in climate in the last two decades could help to explain the observed recent regional increase in SNC disease severity. The resulting model was used to construct a disease prediction map. This map showed an accuracy equivalent to the currently available SNC aerial survey. The prediction model, however, is able to produce a continuous prediction surface, more suitable for testing and appropriate for assisting in disease management and research. A strong relationship between mature stand canopy defoliation and the Landsat TM indices greenness and brightness, indicates that it is possible to use satellite imagery to map SNC. In contrast, young stands showed high variability, most likely due to the relatively high proportion of exposed understory vegetation. The possibility of mapping stand defoliation is of great importance because this symptom can be directly linked to tree growth and forest productivity. Satellite imagery can be used in future and in retrospective disease mapping. Close

• 13. [Article] Urban development in coastal Oregon : discrete-choice estimation with spatial autocorrelation

  Development along the Oregon coast is continuing in areas that are known to be hazardous, in spite of strict zoning and other laws. The coast commonly sees erosion that can wash away cliffs and undermine ...

  Citation × Citation Citation Abstract Copy Title: Urban development in coastal Oregon : discrete-choice estimation with spatial autocorrelation Author: Todd, Maribeth Development along the Oregon coast is continuing in areas that are known to be hazardous, in spite of strict zoning and other laws. The coast commonly sees erosion that can wash away cliffs and undermine structures as well as accretion that can bury houses in sand. However the much more acute risk is the potential for a tsunami triggered by an earthquake in the ocean. This paper examines the factors influencing development along the Oregon coast using satellite imagery and other spatial data. An econometric model for land use change at the pixel level is developed. The scale at which the data (satellite imagery) are collected is different from the scale at which development occurs, leading to spatial correlation among pixels that are geographically close to each other. Estimating a standard probit model in this case leads to parameter estimates that are inconsistent. Incorporating a spatial lag of the dependent variable will account for the spatial autocorrelation but makes maximum likelihood estimation nearly impossible so a Bayesian approach is used instead. A Gibb's sampling algorithm is implemented to estimate the conditional distribution of each parameter in the model, from which parameter estimates can be derived. The Bayesian spatial probit estimation is very computationally intensive however the results indicate that the spatial lag is a crucial part of the model. This approach also allows projections of the spatial pattern of future development, unlike estimation methods that sample the data to remove autocorrelation among observations. The spatial lag model is then used to project future development patterns in several regions along the Oregon coast and explore potential applications of this projection model. In particular, predicted development patterns in the tsunami hazard zone are examined in the Waldport area, on the central coast of Oregon. Title: Urban development in coastal Oregon : discrete-choice estimation with spatial autocorrelation Author: Todd, Maribeth Development along the Oregon coast is continuing in areas that are known to be hazardous, in spite of strict zoning and other laws. The coast commonly sees erosion that can wash away cliffs and undermine structures as well as accretion that can bury houses in sand. However the much more acute risk is the potential for a tsunami triggered by an earthquake in the ocean. This paper examines the factors influencing development along the Oregon coast using satellite imagery and other spatial data. An econometric model for land use change at the pixel level is developed. The scale at which the data (satellite imagery) are collected is different from the scale at which development occurs, leading to spatial correlation among pixels that are geographically close to each other. Estimating a standard probit model in this case leads to parameter estimates that are inconsistent. Incorporating a spatial lag of the dependent variable will account for the spatial autocorrelation but makes maximum likelihood estimation nearly impossible so a Bayesian approach is used instead. A Gibb's sampling algorithm is implemented to estimate the conditional distribution of each parameter in the model, from which parameter estimates can be derived. The Bayesian spatial probit estimation is very computationally intensive however the results indicate that the spatial lag is a crucial part of the model. This approach also allows projections of the spatial pattern of future development, unlike estimation methods that sample the data to remove autocorrelation among observations. The spatial lag model is then used to project future development patterns in several regions along the Oregon coast and explore potential applications of this projection model. In particular, predicted development patterns in the tsunami hazard zone are examined in the Waldport area, on the central coast of Oregon. Close

• 14. [Article] Effect of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley : research plan, June 1997

  Little research has been directed toward determining the status and ecological role of riparian areas in agricultural landscapes of the Willamette Valley, Oregon. A research project has been designed to ...

  Citation × Citation Citation Abstract Copy Title: Effect of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley : research plan, June 1997 Author: Moser, Thomas J., Schuft, Michael J., Wigington, P.J., Herlihy, Alan T., Van Sickle, John, Kaufmann, Phillip R., McAllister, Lynne S. Little research has been directed toward determining the status and ecological role of riparian areas in agricultural landscapes of the Willamette Valley, Oregon. A research project has been designed to contribute to the development and evaluation of alternative future scenarios and to improve the basic understanding of the role of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley. The objectives of the research are: (1) to quantify relationships between riparian attributes at varying spatial scales and stream ecological condition, and (2) to estimate the influence of selected riparian area-agricultural configurations on the indicators of stream ecological condition. To address these objectives, remotely-sensed imagery (aerial photography and thematic mapper satellite imagery) will be used to quantify land cover at multiple spatial scales (i.e., stream reach, stream network, watershed), from which riparian vegetation function, land use stressor, and stream network structure indicators (i.e., potential explanatory variables) are derived for 41 study watersheds. Title: Effect of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley : research plan, June 1997 Author: Moser, Thomas J., Schuft, Michael J., Wigington, P.J., Herlihy, Alan T., Van Sickle, John, Kaufmann, Phillip R., McAllister, Lynne S. Little research has been directed toward determining the status and ecological role of riparian areas in agricultural landscapes of the Willamette Valley, Oregon. A research project has been designed to contribute to the development and evaluation of alternative future scenarios and to improve the basic understanding of the role of riparian areas on the ecological condition of small, perennial streams in agricultural landscapes of the Willamette Valley. The objectives of the research are: (1) to quantify relationships between riparian attributes at varying spatial scales and stream ecological condition, and (2) to estimate the influence of selected riparian area-agricultural configurations on the indicators of stream ecological condition. To address these objectives, remotely-sensed imagery (aerial photography and thematic mapper satellite imagery) will be used to quantify land cover at multiple spatial scales (i.e., stream reach, stream network, watershed), from which riparian vegetation function, land use stressor, and stream network structure indicators (i.e., potential explanatory variables) are derived for 41 study watersheds. Close

• 15. [Article] Small Unmanned Aircraft Systems (UAS) for Engineering Inspections and Geospatial Mapping

  Small unmanned aircraft systems (UAS) carrying consumer-grade nonmetric cameras are increasingly utilized to generate high-resolution 3D geospatial data. Low cost, ease of operation, widespread availability ...

  Citation × Citation Citation Abstract Copy Title: Small Unmanned Aircraft Systems (UAS) for Engineering Inspections and Geospatial Mapping Author: Javadnejad, Farid Small unmanned aircraft systems (UAS) carrying consumer-grade nonmetric cameras are increasingly utilized to generate high-resolution 3D geospatial data. Low cost, ease of operation, widespread availability and low altitude maneuvering capabilities of UAS, as well as the rapid development of technology and methods, make UAS-based photogrammetry applicable to many civil engineering applications such as visualization, 3D mapping, progress monitoring, construction, structural inspection, maintenance, and monitoring. Using computer vision techniques, Structure from Motion (SfM) and Multi-View Stereo (MVS), it is possible to reconstruct 3D scenes from inexpensive, consumer-grade cameras mounted on a UAS. Despite the increasing popularity of UAS, significant research questions remain regarding the accuracy of UAS-based mapping products. In addition, new tools and methods are required to manage and process the vast amount of data generated by UAS. This research explores several novel approaches to address some of these needs in the field of UAS-based photogrammetry. First, a new approach is developed for supplementing the 3D point clouds derived from UAS imagery with thermal infrared (TIR) imagery. Currently, there are several challenges for reconstructing accurate 3D scenes or point clouds solely from overlapping TIR imagery. For instance, consumer-grade TIR cameras have relatively low resolution and a narrow field view; moreover, such cameras usually generate images with blurred edges and textures. An approach is proposed and evaluated for generating 3D TIR-RGB point clouds utilizing coacquired TIR and RGB images. First, a 3D point cloud is generated using the RGB images; afterward, the TIR data is attributed to the 3D point cloud using a boresight technique. Using the proposed approach, dense point clouds are generated that contain both RGB and TIR information. Such an approach can be beneficial for many thermal mapping and inspection projects, including heat loss inspection, non-destructive testing of structures, and electrical parts inspection for power transmission. Second, the research examines the feasibility of utilizing UAS-based photogrammetry for detecting the change of above-ground pipelines. Since it is inexpensive to fly, UAS are ideal for inspecting, monitoring, and detecting changes in the sites over time. In the researched approach, repetitive UAS flights were conducted to derive 3D digital terrain models in order to detect and measure the movement of pipelines in the scene. The results are compared with displacement measurements taken from conventional ground surveys using real-time kinematic (RTK) global navigation satellite system (GNSS) receivers and total stations. Thirdly, this study introduces new dense point cloud quality factors (DPQF) to use as proxy indicators for assessing the accuracy of SfM-MVS dense point clouds. Simulated and empirical experiments are used to assess the accuracy of image-based 3D reconstructed models with respect to different data collection and site condition scenarios. The spatial correlation between the DPQFs and the reconstruction error is investigated and interpreted for multiple experiments. The results of this study show that the DPQF can be a helpful additional field of information for 3D point clouds. Last, this research introduces a new web GIS tool, named BridgeDex, for management of time-aware series of high-resolution bridge inspection images, such as images collected from handheld digital cameras or cameras on UAS. This tool can be used to manage and query bridge inspection images, bridge reports, and other relevant metadata. This web-based prototype provides the user a simple interface for viewing, panning and zooming in and out of bridge imagery collected over the years as a result of numerous bridge inspections. The tool provides the user an intuitive, organized method for evaluating and managing bridge inspection data. Title: Small Unmanned Aircraft Systems (UAS) for Engineering Inspections and Geospatial Mapping Author: Javadnejad, Farid Small unmanned aircraft systems (UAS) carrying consumer-grade nonmetric cameras are increasingly utilized to generate high-resolution 3D geospatial data. Low cost, ease of operation, widespread availability and low altitude maneuvering capabilities of UAS, as well as the rapid development of technology and methods, make UAS-based photogrammetry applicable to many civil engineering applications such as visualization, 3D mapping, progress monitoring, construction, structural inspection, maintenance, and monitoring. Using computer vision techniques, Structure from Motion (SfM) and Multi-View Stereo (MVS), it is possible to reconstruct 3D scenes from inexpensive, consumer-grade cameras mounted on a UAS. Despite the increasing popularity of UAS, significant research questions remain regarding the accuracy of UAS-based mapping products. In addition, new tools and methods are required to manage and process the vast amount of data generated by UAS. This research explores several novel approaches to address some of these needs in the field of UAS-based photogrammetry. First, a new approach is developed for supplementing the 3D point clouds derived from UAS imagery with thermal infrared (TIR) imagery. Currently, there are several challenges for reconstructing accurate 3D scenes or point clouds solely from overlapping TIR imagery. For instance, consumer-grade TIR cameras have relatively low resolution and a narrow field view; moreover, such cameras usually generate images with blurred edges and textures. An approach is proposed and evaluated for generating 3D TIR-RGB point clouds utilizing coacquired TIR and RGB images. First, a 3D point cloud is generated using the RGB images; afterward, the TIR data is attributed to the 3D point cloud using a boresight technique. Using the proposed approach, dense point clouds are generated that contain both RGB and TIR information. Such an approach can be beneficial for many thermal mapping and inspection projects, including heat loss inspection, non-destructive testing of structures, and electrical parts inspection for power transmission. Second, the research examines the feasibility of utilizing UAS-based photogrammetry for detecting the change of above-ground pipelines. Since it is inexpensive to fly, UAS are ideal for inspecting, monitoring, and detecting changes in the sites over time. In the researched approach, repetitive UAS flights were conducted to derive 3D digital terrain models in order to detect and measure the movement of pipelines in the scene. The results are compared with displacement measurements taken from conventional ground surveys using real-time kinematic (RTK) global navigation satellite system (GNSS) receivers and total stations. Thirdly, this study introduces new dense point cloud quality factors (DPQF) to use as proxy indicators for assessing the accuracy of SfM-MVS dense point clouds. Simulated and empirical experiments are used to assess the accuracy of image-based 3D reconstructed models with respect to different data collection and site condition scenarios. The spatial correlation between the DPQFs and the reconstruction error is investigated and interpreted for multiple experiments. The results of this study show that the DPQF can be a helpful additional field of information for 3D point clouds. Last, this research introduces a new web GIS tool, named BridgeDex, for management of time-aware series of high-resolution bridge inspection images, such as images collected from handheld digital cameras or cameras on UAS. This tool can be used to manage and query bridge inspection images, bridge reports, and other relevant metadata. This web-based prototype provides the user a simple interface for viewing, panning and zooming in and out of bridge imagery collected over the years as a result of numerous bridge inspections. The tool provides the user an intuitive, organized method for evaluating and managing bridge inspection data. Close

• 16. [Article] "Style upon style": The Handmaid's Tale as a palimpsest of genres

  This thesis undertakes an examination of Margaret Atwood’s 1985 novel, The Handmaid’s Tale, as a layering of genres. A futuristic dystopia that imagines late twentieth-century America as having fallen ...

  Citation × Citation Citation Abstract Copy Title: "Style upon style": The Handmaid's Tale as a palimpsest of genres Author: Boulware, Taylor J. This thesis undertakes an examination of Margaret Atwood’s 1985 novel, The Handmaid’s Tale, as a layering of genres. A futuristic dystopia that imagines late twentieth-century America as having fallen into neo-Puritanism and totalitarianism following widespread infertility and violence, The Handmaid’s Tale invites contemplation of various forms of fundamentalism, radicalism, and sexual politics. Atwood’s use of palimpsestic imagery to convey a layered experience of time extends to the generic complexity of The Handmaid’s Tale. Using the image of the palimpsest as the controlling metaphor, I survey the ways in which the novel can be read as an historical novel, satire, and postmodern text, exploring the ways in which the novel embodies and extends the defining characteristics of each genre. These genres share the common trait of functioning as social commentary. Thus, an examination of the novel’s layering of genres works to provide greater insights into the ways in which Atwood is interrogating the mid-1980s cultural milieu to which she was responding and from which she was writing. Title: "Style upon style": The Handmaid's Tale as a palimpsest of genres Author: Boulware, Taylor J. This thesis undertakes an examination of Margaret Atwood’s 1985 novel, The Handmaid’s Tale, as a layering of genres. A futuristic dystopia that imagines late twentieth-century America as having fallen into neo-Puritanism and totalitarianism following widespread infertility and violence, The Handmaid’s Tale invites contemplation of various forms of fundamentalism, radicalism, and sexual politics. Atwood’s use of palimpsestic imagery to convey a layered experience of time extends to the generic complexity of The Handmaid’s Tale. Using the image of the palimpsest as the controlling metaphor, I survey the ways in which the novel can be read as an historical novel, satire, and postmodern text, exploring the ways in which the novel embodies and extends the defining characteristics of each genre. These genres share the common trait of functioning as social commentary. Thus, an examination of the novel’s layering of genres works to provide greater insights into the ways in which Atwood is interrogating the mid-1980s cultural milieu to which she was responding and from which she was writing. Close

• 17. [Article] Planning Under Uncertainty for Unmanned Aerial Vehicles

  Unmanned aerial vehicle (UAV) technology has grown out of traditional research and military applications and has captivated the commercial and consumer markets, showing the ability to perform a spectrum ...

  Citation × Citation Citation Abstract Copy Title: Planning Under Uncertainty for Unmanned Aerial Vehicles Author: Skeele, Ryan Unmanned aerial vehicle (UAV) technology has grown out of traditional research and military applications and has captivated the commercial and consumer markets, showing the ability to perform a spectrum of autonomous functions. This technology has the capability of saving lives in search and rescue, fighting wildfires in environmental monitoring, and delivering time dependent medicine in package delivery. These examples demonstrate the potential impact this technology will have on our society. However, it is evident how sensitive UAVs are to the uncertainty of the physical world. In order to properly achieve the full potential of UAVs in these markets, robust and efficient planning algorithms are needed. This thesis addresses the challenge of planning under uncertainty for UAVs. We develop a suite of algorithms that are robust to changes in the environment and build on the key areas of research needed for utilizing UAVs in a commercial setting. Throughout this research three main components emerged: monitoring targets in dynamic environments, exploration with unreliable communication, and risk-aware path planning. We use a realistic fire simulation to test persistent monitoring in an uncertain environment. The fire is generated using the standard program for modeling wildfire, FARSITE. This model was used to validate a weighted-greedy approach to monitoring clustered points of interest (POIs) over traditional methods of tracking a fire front. We implemented the algorithm on a commercial UAV to demonstrate the deployment capability. Dynamic monitoring has limited potential if if coordinated planning is fallible to uncertainty in the world. Uncertain communication can cause critical failures in coordinated planning algorithms. We develop a method for coordinated exploration of a multi-UAV team with unreliable communication and limited battery life. Our results show that the proposed algorithm, which leverages meeting, sacrificing, and relaying behavior, increases the percentage of the environment explored over a frontier-based exploration strategy by up to 18%. We test on teams of up to 8 simulated UAVs and 2 real UAVs able to cope with communication loss and still report improved gains. We demonstrate this work with a pair of custom UAVs in an indoor office environment. We introduce a novel approach to incorporating and addressing uncertainty in planning problems. The proposed Risk-Aware Graph Search (RAGS) algorithm combines traditional deterministic search techniques with risk-aware planning. RAGS is able to trade off the number of future path options, as well as the mean and variance of the associated path cost distributions to make online edge traversal decisions that minimize the risk of executing a high-cost path. The algorithm is compared against existing graphsearch techniques on a set of graphs with randomly assigned edge costs, as well as over a set of graphs with transition costs generated from satellite imagery data. In all cases, RAGS is shown to reduce the probability of executing high-cost paths over A*, D* and a greedy planning approach. High level planning algorithms can be brittle in dynamic conditions where the environment is not modeled perfectly. In developing planners for uncertainty we ensure UAVs will be able to operate in conditions outside the scope of prior techniques. We address the need for robustness in robotic monitoring, coordination, and path planning tasks. Each of the three methods introduced were tested in simulated and real environments, and the results show improvement over traditional algorithms. Title: Planning Under Uncertainty for Unmanned Aerial Vehicles Author: Skeele, Ryan Unmanned aerial vehicle (UAV) technology has grown out of traditional research and military applications and has captivated the commercial and consumer markets, showing the ability to perform a spectrum of autonomous functions. This technology has the capability of saving lives in search and rescue, fighting wildfires in environmental monitoring, and delivering time dependent medicine in package delivery. These examples demonstrate the potential impact this technology will have on our society. However, it is evident how sensitive UAVs are to the uncertainty of the physical world. In order to properly achieve the full potential of UAVs in these markets, robust and efficient planning algorithms are needed. This thesis addresses the challenge of planning under uncertainty for UAVs. We develop a suite of algorithms that are robust to changes in the environment and build on the key areas of research needed for utilizing UAVs in a commercial setting. Throughout this research three main components emerged: monitoring targets in dynamic environments, exploration with unreliable communication, and risk-aware path planning. We use a realistic fire simulation to test persistent monitoring in an uncertain environment. The fire is generated using the standard program for modeling wildfire, FARSITE. This model was used to validate a weighted-greedy approach to monitoring clustered points of interest (POIs) over traditional methods of tracking a fire front. We implemented the algorithm on a commercial UAV to demonstrate the deployment capability. Dynamic monitoring has limited potential if if coordinated planning is fallible to uncertainty in the world. Uncertain communication can cause critical failures in coordinated planning algorithms. We develop a method for coordinated exploration of a multi-UAV team with unreliable communication and limited battery life. Our results show that the proposed algorithm, which leverages meeting, sacrificing, and relaying behavior, increases the percentage of the environment explored over a frontier-based exploration strategy by up to 18%. We test on teams of up to 8 simulated UAVs and 2 real UAVs able to cope with communication loss and still report improved gains. We demonstrate this work with a pair of custom UAVs in an indoor office environment. We introduce a novel approach to incorporating and addressing uncertainty in planning problems. The proposed Risk-Aware Graph Search (RAGS) algorithm combines traditional deterministic search techniques with risk-aware planning. RAGS is able to trade off the number of future path options, as well as the mean and variance of the associated path cost distributions to make online edge traversal decisions that minimize the risk of executing a high-cost path. The algorithm is compared against existing graphsearch techniques on a set of graphs with randomly assigned edge costs, as well as over a set of graphs with transition costs generated from satellite imagery data. In all cases, RAGS is shown to reduce the probability of executing high-cost paths over A*, D* and a greedy planning approach. High level planning algorithms can be brittle in dynamic conditions where the environment is not modeled perfectly. In developing planners for uncertainty we ensure UAVs will be able to operate in conditions outside the scope of prior techniques. We address the need for robustness in robotic monitoring, coordination, and path planning tasks. Each of the three methods introduced were tested in simulated and real environments, and the results show improvement over traditional algorithms. Close

• 18. [Article] Site formation at Ayia Varvara Asprokremnos and predictive modeling for neolithic sites, Cyprus

  Site formation processes at Ayia Varvara Asprokremnos, a potentially early Neolithic archaeological site on Cyprus, are examined in order to build a larger predictive model. The study area immediate to ...

  Citation × Citation Citation Abstract Copy Title: Site formation at Ayia Varvara Asprokremnos and predictive modeling for neolithic sites, Cyprus Author: Barnett, Darby E. Site formation processes at Ayia Varvara Asprokremnos, a potentially early Neolithic archaeological site on Cyprus, are examined in order to build a larger predictive model. The study area immediate to the site encompasses 6.33 hectares and includes the site and alluvial terraces on both sides of the Gialias River. Fourteen soil map units, largely developed on Holocene colluvium, were identified. Stratigraphic profiles of the excavation trenches indicate a buried A horizon overlying what is thought to be a Pre-Pottery Neolithic B cultural component. Construction of a checkdam stopped site erosion and promoted the burial and preservation of a stratified archaeological sequence. The site is located next to a contact between the Lefkara Formation (limestone) and the Upper Pillow Basalts where vitreous chert commonly occurs on the island. Using the geoarchaeological data collected from Ayia Varvara Asprokremnos, satellite imagery and Geographic Information Systems data, a model was built the location of other further Neolithic Quarry sites on the island. The predictive model considers proximity to the contact, proximity to a 4th to 7th order stream, landscape position and relative level of ground disturbance. Over 38 areas were identified on 23 1:5,000 scale maps that could be explored by field survey and sub-surface testing. Title: Site formation at Ayia Varvara Asprokremnos and predictive modeling for neolithic sites, Cyprus Author: Barnett, Darby E. Site formation processes at Ayia Varvara Asprokremnos, a potentially early Neolithic archaeological site on Cyprus, are examined in order to build a larger predictive model. The study area immediate to the site encompasses 6.33 hectares and includes the site and alluvial terraces on both sides of the Gialias River. Fourteen soil map units, largely developed on Holocene colluvium, were identified. Stratigraphic profiles of the excavation trenches indicate a buried A horizon overlying what is thought to be a Pre-Pottery Neolithic B cultural component. Construction of a checkdam stopped site erosion and promoted the burial and preservation of a stratified archaeological sequence. The site is located next to a contact between the Lefkara Formation (limestone) and the Upper Pillow Basalts where vitreous chert commonly occurs on the island. Using the geoarchaeological data collected from Ayia Varvara Asprokremnos, satellite imagery and Geographic Information Systems data, a model was built the location of other further Neolithic Quarry sites on the island. The predictive model considers proximity to the contact, proximity to a 4th to 7th order stream, landscape position and relative level of ground disturbance. Over 38 areas were identified on 23 1:5,000 scale maps that could be explored by field survey and sub-surface testing. Close

• 19. [Article] Waning magmatic activity along the Southern Explorer Ridge revealed through fault restoration of rift topography

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. American Geophysical Union – Geochemistry, Geophysics, Geosystems - G³ This is the ...

  Citation × Citation Citation Abstract Copy Title: Waning magmatic activity along the Southern Explorer Ridge revealed through fault restoration of rift topography Author: Chadwick Jr., W. W., Tivey, M. A., Deschamps, A., Embley, R. W. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. American Geophysical Union – Geochemistry, Geophysics, Geosystems - G³ This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gc/. Title: Waning magmatic activity along the Southern Explorer Ridge revealed through fault restoration of rift topography Author: Chadwick Jr., W. W., Tivey, M. A., Deschamps, A., Embley, R. W. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. American Geophysical Union – Geochemistry, Geophysics, Geosystems - G³ This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gc/. Close

• 20. [Article] The evolution of mapping habitat for northern spotted owls (Strix occidentalis caurina): A comparison of photo-interpreted, Landsat-based, and lidar-based habitat maps

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: The evolution of mapping habitat for northern spotted owls (Strix occidentalis caurina): A comparison of photo-interpreted, Landsat-based, and lidar-based habitat maps Author: Ackers, Steven H., Dugger, Katie M., Davis, Raymond J., Olsen, Keith A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/remote-sensing-of-environment. Title: The evolution of mapping habitat for northern spotted owls (Strix occidentalis caurina): A comparison of photo-interpreted, Landsat-based, and lidar-based habitat maps Author: Ackers, Steven H., Dugger, Katie M., Davis, Raymond J., Olsen, Keith A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/remote-sensing-of-environment. Close