Dissertations / Theses: 'Aerial photography in forestry'

1

Holmström, Hampus. "Data acquisition for forestry planning by remote sensing based sample plot imputation /." Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-6086-7.pdf.

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2

Metzler, Jacob W. "Use of Multi-temporal IKONOS and LANDSAT ETM+ Satellite Imagery to Determine Forest Stand Conditions in Northern Maine." Fogler Library, University of Maine, 2004. http://www.library.umaine.edu/theses/pdf/MetzlerJW2004.pdf.

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3

Bleier, Mary F. "Use of prior distributions from aerial photographs in forest inventory." Thesis, Virginia Tech, 1986. http://hdl.handle.net/10919/41543.

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Bayesian estimates of gross cubic- foot volume per acre were computed for four stand types (plantation pine, natural pine. hardwood. and mixed wood stands) using aerial photo volume tables as the prior information source. Aerial photographs provided a reliable source of information even though most photographs were nearly five years old. For a given level of precision within a particular stand, Bayesian methods reduced the required field sample size up to 50% using all or half of the prior information available. Those priors which utilized a regression or a regression/topographic correction in the estimation of photo heights required less field information for the given precision level than those priors which used uncorrected or topographic corrected photo heights. In order to obtain meaningful gains in sample size reduction corrections to the estimated photo heights should be made. Although the uncorrected prior produced generally less biased estimates. the reduction in sample size was not as large as that observed using other prior types. Greater gains were attributed to the better accuracy of the prior distribution. Although Bayesian methods are biased, it appeared that these methods tempered severely biased prior distributions. In the hardwood stand for example, the average bias present in the photo volume data amounted to -140%. After combining the prior with the field sample, the greatest average bias was -50%. Bayesian methods performed better than the traditional estimation methods in terms of precision. In a one to one comparison. the Bayes standard error was consistently less than its non-Bayes counterpart. The one exception to this trend was the regression prior from the hardwood stand. The poor performance of the prior was due to the weak height regression correction equation. Modal priors utilized were not subject to the extreme input values for prior distribution development as their conservative empirical prior counterparts were. Less overall variation was observed 1n the estimated values. Under the conditions for mode selection set forth in this project, modal priors provided another good source of prior information.
Master of Science

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4

Pacurari, Doru I. "Evaluation of the use of remotely sensed images to speciate mixed Appalachian forests." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1550.

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Thesis (M.S.)--West Virginia University, 2000.
Title from document title page. Document formatted into pages; contains x, 128 p. : ill. (some col.), maps (some col.) Vita. Includes abstract. Includes bibliographical references (p. 116-121).

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5

Korpela, Ilkka. "Individual tree measurements by means of digital aerial photogrammetry." Helsinki : Finnish Forest Research Institute, Finnish Society of Forest Science, 2004. http://catalog.hathitrust.org/api/volumes/oclc/55872310.html.

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6

Holt, Ryan Samuel. "Three enabling technologies for vision-based, forest-fire perimeter surveillance using multiple unmanned aerial systems /." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1894.pdf.

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7

Zagalikis, Georgios D. "Estimation of forest stand parameters using digital orthorectified aerial photographs." Thesis, University of Aberdeen, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274879.

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Ground based forest inventory surveys can provide highly accurate measurements of tree and stand characteristics, but are time-consuming and costly, and therefore typically limited to number of sample plots. Estimating tree and stand characteristics from digitised aerial photographs can provide measurements from the whole stand, but is less accurate. The goal of this study was to evaluate the application of scanned, stereo aerial photography and digital photogrammetry in combination with tree crown delineation techniques to measure tree and stand characteristics in two sites in Scotland, Rosarie and Leanachan forests. Existing medium-resolution scanned images of true colour aerial photographs (1:10,000) were used to derive Digital Elevation Models (DEMs) of the forest canopy and digital orthophotographs. Tree crown delineation techniques were used on the derived digital orthophotographs and tree crown measurements including crown area and coordinates of each crown were derived. The DEMs in combination with Digital Terrain Models (DTMs) derived from digital contour maps, were used for the estimation of tree and stand heights. Equations derived from regression analysis of individual tree measurements on the ground, and the orthophotographs from Rosarie forest, were used for the estimation of tree and stand characteristics of both sites. For Rosarie forest the estimations of stand top height, basal area, stand volume stand biomass and stand density (~23.7%) were similar with the ground measured stand characteristics (±10%), where as for Leanachan forest the estimations were less accurate due to the non-optimum illumination conditions during the acquisition of the aerial photographs. The level of accuracy achieved in this study is adequate for measuring tree and stand characteristics, if the acquisition conditions of aerial photographs are optimal. Higher level of accuracy may be possible, but requires more accurate DTMs, possibly derived using active airborne remote sensing sensors.

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Wiles, Steven Jay. "Evaluation of photographic properties for area estimation." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/44695.

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From the known image positional errors on aerial photographs, this thesis computes and evaluates acreage estimation errors. Four hypothetical tracts were used in simulating aerial photographs with 104 different camera orientation combinations. Flying heights of 4000 and 6000 feet, focal lengths of 24 and 50 millimeters with and without lens distortion, and tilts of 0, 3, 6, and 12 degrees were simulated. The 416 photographs were all simulated with the camera exposure station centered above the midpoint of the respective tract's bounding rectangle. The topographic relief of the tracts ranged from 19 feet in the Coastal Plain to 105 feet in the Piedmont.

It was found that lens focal length did not have an independent effect on the acreage estimates. Relief error, the lowest, averaged -0.080%. In comparison, small errors in calculating scale were shown to be larger than relief errors. Tilt was recommended to be limited to six degrees, averaging +1.6% error at six degrees tilt. Because of its positive exponential nature when the tracts are centered, tilt can induce large biases. including tilts from zero to six degrees,the average was 0.634%. Lens distortion error averaged -0.686%. Overall, the average acreage error was 0.363% for simulations up to and including six degrees of tilt with and without lens distortion. This result is for centered tracts, and it was felt many of the errors were compensating given this situation. In conclusion, the photographic images can estimate areas to $1%, however, additional errors are imparted during actual measurement of the photographs.
Master of Science

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9

Magnvall, Andreas, and Alexander Henne. "Real-time Aerial Photograph Alignment using Feature Matching." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-176658.

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With increased mobile hardware capabilities, improved UAVs and modern algorithms, accurate maps can be created in real-time by capturing overlapping photographs of the ground. A method for mapping that can be used is to position photos by relying purely on the GPS position and altitude. However, GPS inaccuracies will be visible in the created map. In this paper, we will instead present a method for aligning the photos correctly with the help of feature matching. Feature matching is a well-known method which analyses two photos to find similar parts. If an overlap exists, feature matching can be used to find and localise those parts, which can be used for positioning one image over the other at the overlap. When repeating the process, a whole map can be created. For this purpose, we have also evaluated a selection of feature detection and matching algorithms. The algorithm found to be the best was SIFT with FLANN, which was then used in a prototype for creating a complete map of a forest. Feature matching is in many cases superior to GPS positioning, although it cannot be fully depended on as failed or incorrect matching is a common occurrence.

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10

Heer, Richard C. "Estimation of seedling density and evaluation of woody competition in young loblolly pine plantations using 35mm color aerial photography." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/94464.

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The potential for using large scale, small format aerial photography to obtain seedling density and woody competition information was investigated. Factors affecting photo interpretation of seedlings were examined and equations to predict seedling density and woody competition levels were developed and evaluated. Two scales of imagery, 1:4000 and 1:6000 were considered to compare their relative merits for these purposes. Greater age of the seedlings and their inherent development generally served to improve photo interpretation. The amount of woody competition present in the plots tended to hinder seedling identification at the 1:4000 scale, while enhancing it when 1:6000 scale data was used. Seedling density estimation and evaluation of competition through Free-To-Grow classification predictions yielded results comparable to ground surveys. Estimation of total groundline basal area in all woody competition, and classification of the plots by the amount of hard-to-control competition they contained, were less successful. These results may have been due in part to the partial leaf fall that occurred prior to obtaining the imagery. Many of the results found in this study favored the larger scale (1:4000) imagery, and its use for the procedures described is recommended.
M.S.

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11

Pilger, Neal, and University of Lethbridge Faculty of Arts and Science. "Canopy reflectance modeling of forest stand volume." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2004, 2004. http://hdl.handle.net/10133/230.

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Three-dimensional canopy relectance models provide a physical-structural basis to satellite image analysis, representing a potentially more robust, objective and accurate approach for obtaining forest cover type and structural information with minimal ground truth data. The Geometric Optical Mutual Shadowing (GOMS) canopy relectance model was run in multiple-forward-mode (MFM) using digital multispectral IKONOS satellite imagery to estimate tree height and stand volume over 100m2 homogeneous forest plots in mountainous terrain, Kananaskis, Alberta. Height was computed within 2.7m for trembling aspen and 1.8m fr lodgepole pine, with basal area estimated within 0.05m2. Stand volume, estimated as the product of mean tree height and basal area, had an absolute mean difference from field measurements of 0.85m3/100m2 and 0.61m3/100m2 for aspen and pine, respectively.
xiii, 143 leaves : ill. (some col.) ; 29 cm.

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Soenen, Scott, and University of Lethbridge Faculty of Arts and Science. "Remote sensing of montane forest structure and biomass : a canopy relectance model inversion approach." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2006, 2006. http://hdl.handle.net/10133/281.

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The multiple-forward-mode (MFM) inversion procedure is a set of methods for indirect canopy relectance model inversion using look-up tables (LUT). This thesis refines the MFM technique with regard to: 1) model parameterization for the MFM canopy reflectance model executions and 2) methods for limiting or describing multiple solutions. Forest stand structure estimates from the inversion were evaluated using 40 field validation sites in the Canadian Rocky Mountains. Estimates of horizontal and vertical crown radius were within 0.5m and 0.9m RMSE for both conifer and deciduous species. Density estimates were within 590 stems/ha RMSE for conifer and 310 stems/ha RMSE for deciduous. The most effective inversion method used a variable spectral domain with constrained, fine increment LUTs. A biomass estimation method was also developed using empirical relationships with crown area. Biomass density estimates using the MFM method were similar to estimates produced using other multispectral analysis methods (RMSE=50t/ha).
xvi, 156 leaves : ill. (some col.), maps ; 29 cm.

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13

Grotefendt, Richard. "Accurate and cost-effective natural resource data from super large scale aerial photography /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/5454.

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14

Johnson, Ryan L., and University of Lethbridge Faculty of Arts and Science. "Airborne remote sensing of forest leaf area index in mountainous terrain." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2000, 2000. http://hdl.handle.net/10133/90.

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Leaf area index (LAI) provides forestry information that is important for regional scale ecological models and in studies of global change. This research examines the effects of mountainous terrain on the radiometric properties of multispectral CASI imagery in estimating ground-based optical measurements of LAI, obtained using the TRAC and LAI- 2000 systems. Field and image data were acquired summer 1998 in Kananaskis, Alberta, Canada. To account for the influence of terrain a new modified approach using the Li and Strahler Geometric Optical Mutual Shadowing (GOMS) model in 'multiple forward mode' (MFM) was developed. This new methodology was evaluated against four traditional radiometric corrections used in comination with spectral mixture analysis (SMA) and NDVI. The MFM approach provided the best overall predictions of LAI measured with ground-based optical instruments, followed by terrain normalized SMA, SMA without terrain normalization and NDVI.
xiv, 151 leaves : ill. (some col.), map ; 29 cm.

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15

Blinn, Christine Elizabeth. "Estimation of Important Scenic Beauty Covariates from Remotely Sensed Data." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/33656.

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The overall objective of this study was to determine if remotely sensed data could be used to model scenic beauty. Terrestrial digital images from within forest stands located in Prince Edward Gallion State Forest near Farmville, Virginia were rated for their scenic beauty by a group of students to obtain scenic beauty estimates (SBEs). Since the inter-rater reliability was low for the SBEs, they were not used in the modeling efforts. Instead, stand parameters (collected on tenth acre plots) that have been used in scenic beauty prediction models, like mean diameter at breast height (dbh), were the dependent variables in regression analyses. A color-infrared aerial photograph from the National Aerial Photography Program (NAPP) was scanned to achieve a pixel ground resolution of one meter. The digital aerial photograph was rectified and used as the remotely sensed data. Since the aerial photograph was taken in April, only conifer stands were used in the analyses. Summary statistics were obtained from a 23 by 23 window around plot locations in three images: the original image, a texture image created with the variance algorithm and a 7x7 window, and the first principal component image. The summary statistics were used as the independent variables in regression analyses. The mean texture digital number for the green band predicted the mean dbh of a plot with an R2 of 0.623. A maximum of 44.3 and 27.4 percent of the variability in trees per acre and basal area per acre, respectively, was explained by the models developed in this study. It seems unlikely that the remotely sensed forest stand variables would perform well as surrogates for field measurements used in scenic quality models.
Master of Science

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16

Jodry, Réal. "La télédétection multibande aéroportée MEIS II et DAEDALUS MSS appliquée à la cartographie forestière de la station Simoncouche /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1996. http://theses.uqac.ca.

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17

Brandtberg, Tomas. "Automatic individual tree-based analysis of high spatial resolution remotely sensed data /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5852-8.pdf.

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18

Cooper, Joseph L. "Supporting Flight Control for UAV-Assisted Wilderness Search and Rescue Through Human Centered Interface Design." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2140.pdf.

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19

Greenwood, Sarah. "Investigating the response of subtropical forests to environmental variation through the study of the Abies kawakamii treelines in Taiwan." Thesis, University of Stirling, 2014. http://hdl.handle.net/1893/21561.

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Altitudinal treeline advance represents a sensitive and well-studied example of species response to climate warming. Although a great deal of work has been conducted globally, few studies have considered subtropical alpine treelines and little is known about their structure and function. This research aims to investigate the response of high altitude forests in Taiwan to climate variation by characterising treeline advance in the area, exploring the mechanisms driving the advance, and considering the consequences of advance for the wider community. The thesis consists of a general introduction to the topic followed by a series of papers, exploring: (1) Possible consequences of treeline shifts for biodiversity and ecosystem function. (2) The advance of the Abies kawakamii treeline through aerial photograph analysis. (3) The changes in growth rate of Abies kawakamii at treeline and the influence of altitude and temperature on growth. (4) Regeneration patterns at treeline and the importance of microclimate and topographic sheltering. (5) Consequences of the range shift for the wider forest community. The work is then concluded with a general discussion and synthesis. The main aims of this work are therefore to characterise and understand the pattern and pace of treeline advance and forest structural change throughout the Central Mountain Range of Taiwan. Treeline advance is characterised through the study of repeat aerial photographs and the mechanisms behind the observed shift are explored through the study of two key responses associated with forest advance: tree growth at treeline and seedling establishment beyond treeline. The consequences of treeline advance for the wider subalpine community are investigated through the study of epiphytic lichen communities at treeline sites. This investigation of an understudied region will allow for improved understanding of treeline response at a global scale.

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20

McManamay, Rachel Harris. "Assessing the Impacts of Balsam Woolly Adelgid (Adelges Piceae Ratz.) and Anthropogenic Disturbance on the Stand Structure and Mortality of Fraser Fir (Abies Fraseri (Pursh) Poir.) in the Black Mountains, North Carolina." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/42759.

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Over the past several decades, naturally occurring populations of Fraser fir (Abies fraseri) in the Black Mountains of North Carolina have been heavily impacted by both direct and indirect anthropogenic disturbances, including logging and logging- associated fires, and high mortality rates due to the introduction of the exotic insect, balsam woolly adelgid (BWA) (Adelges piceae). The decline in Fraser fir is particularly concern because it serves as a foundation species within the spruce-fir forests of the Southern Appalachian Mountains. Our objectives for this research were to 1) use current stand structure to infer whether Fraser fir trees are experiencing a cycle of regeneration-mortality that will lead to eventual decline of the population, 2) determine what role, if any, the site-specific geographic variables of slope, elevation, aspect, and land use history have on stand structure, mortality, and BWA infestation level, and 3) analyze repeat aerial photography to examine broad trends of spruce-fir forest cover change caused by anthropogenic disturbance and the BWA. In order to understand stand structure, mortality, and infestation levels, we conducted detailed field surveys of Fraser fir trees throughout the Black Mountains using 44, fixed-radius circular sampling plots. These plots were placed throughout a series of aspects, elevations, and disturbance types in order to understand geographic variability among these variables. An analysis of 4 repeat aerial photographs and corroborating ground photographs revealed broad spatio-temporal trends of spruce-fir regeneration and mortality from 1954 to 2006. Our results indicate that Fraser fir stands at higher elevations are currently in a state of recovery; whereas stands at lower elevations appear to be more susceptible to BWA-induced mortality. Changes in forest cover area from 1954 to 2006 were influenced greatly by direct and indirect anthropogenic disturbance. Our results call attention to the significant impact that direct and indirect anthropogenic disturbance has had on Fraser fir stand structure, but also provide evidence for the ability of an imperiled ecosystem to recover from high rates of insect caused mortality.
Master of Science

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21

Bradley, Justin Mathew. "Particle Filter Based Mosaicking for Forest Fire Tracking." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2001.pdf.

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22

Wolf, Eric B. "Low-cost large scale aerial photography and the Upland South Folk Cemetery a thesis presented to the Department of Geology and Geography in candidacy for the degree of Master of Science /." Diss., Maryville, Mo. : Northwest Missouri State University, 2006. http://www.nwmissouri.edu/library/theses/WolfEricB/index.htm.

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Thesis (M.S.)--Northwest Missouri State University, 2006.
The full text of the thesis is included in the pdf file. Title from title screen of full text.pdf file (viewed on January 25, 2008) Includes bibliographical references.

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Richards, Daniel L. "Open source UAV platform development for aerial photography." Thesis, California State University, Long Beach, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1587919.

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Aerial photography is an important layer in Geographic Information Systems (GISs), and generally provides the base layer from which many other digital map layers are derived. Capturing these photos from a traditional full-sized airplane is a complex and expensive process. The recent development of Unmanned Aerial Vehicles (UAVs) and associated technology are providing an alternative to the traditional aerial mapping process. UAVs produced by popular commercial vendors are effective at capturing photos, but are highly expensive to acquire, and equally expensive to maintain.

This research project demonstrates the development and successful implementation of a relatively inexpensive ($2000) unmanned aerial vehicle capable of acquiring high-resolution digital aerial photography. The UAV was developed using open source technology and commercially available components. The methods outlined encompass the platform selection, component inventory, design, construction, configuration, implementation, and testing of the UAV, as well as an analysis of the photography produced by the process. This approach can be used by others to implement similar UAV projects.

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24

Simpson, Andrew David. "DEVELOPMENT OF AN UNMANNED AERIAL VEHICLE FOR LOW-COST REMOTE SENSING AND AERIAL PHOTOGRAPHY." UKnowledge, 2003. http://uknowledge.uky.edu/gradschool_theses/191.

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The paper describes major features of an unmanned aerial vehicle, designed undersafety and performance requirements for missions of aerial photography and remotesensing in precision agriculture. Unmanned aerial vehicles have vast potential asobservation and data gathering platforms for a wide variety of applications. The goalof the project was to develop a small, low cost, electrically powered, unmanned aerialvehicle designed in conjunction with a payload of imaging equipment to obtainremote sensing images of agricultural fields. The results indicate that this conceptwas feasible in obtaining high quality aerial images.

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Gurtner, Alex. "Investigation of fisheye lenses for small UAV aerial photography." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/19323/1/Alex_Gurtner_Final_Thesis.pdf.

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Aerial photography obtained by UAVs (Unmanned Aerial Vehicles) is an emerging market for civil applications. Small UAVs are believed to close gaps in niche markets, such as acquiring airborne image data for remote sensing purposes. Small UAVs will be able to fly at low altitudes, in dangerous environments and over long periods of time. However, the small lightweight constructions of these UAVs lead to new problems, such as higher agility leading to more susceptibility to turbulence and limitations in space and payload for sensor systems. This research investigates the use of low-cost fisheye lenses to overcome such problems which theoretically makes the airborne imaging less sensitive to turbulence. The fisheye lens has the benet of a large observation area (large field of view) and doesn't add additional weight to the aircraft, like traditional mechanical stabilizing systems. This research presents the implementation of a fisheye lens for aerial photography and mapping purposes, including theoretical background of fisheye lenses. Based on the unique feature of the distortion being a function of the viewing angle, methods used to derive the fisheye lens distortion are presented. The lens distortion is used to rectify the fisheye images before these images can be used in aerial photography. A detailed investigation into the inner orientation of the camera and inertial sensor is given, as well as the registration of airborne collected images. It was found that the attitude estimation is critical towards accurate mapping using low quality sensors. A loosely coupled EKF filter applied to the GPS and inertial sensor data estimated the attitude to an accuracy of 3-5° (1-sigma) using low-cost sensors typically found in small UAVs. However, the use of image stitching techniques may improve the outcome. On the other hand, lens distortion caused by the fisheye lens can be addressed by rectification techniques and removed to a sub-pixel level. Results of the process present image sequences gathered from a piloted aircraft demonstrating the achieved performance and potential applications towards UAVs. Further, an unforeseen issue with a vibrating part in the lens lead to the need for vibration compensation. The vibration could be estimated to ±1 pixel in 75% of the cases by applying an extended Hough transform to the fisheye images.

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Gurtner, Alex. "Investigation of fisheye lenses for small UAV aerial photography." Queensland University of Technology, 2008. http://eprints.qut.edu.au/19323/.

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Aerial photography obtained by UAVs (Unmanned Aerial Vehicles) is an emerging market for civil applications. Small UAVs are believed to close gaps in niche markets, such as acquiring airborne image data for remote sensing purposes. Small UAVs will be able to fly at low altitudes, in dangerous environments and over long periods of time. However, the small lightweight constructions of these UAVs lead to new problems, such as higher agility leading to more susceptibility to turbulence and limitations in space and payload for sensor systems. This research investigates the use of low-cost fisheye lenses to overcome such problems which theoretically makes the airborne imaging less sensitive to turbulence. The fisheye lens has the benet of a large observation area (large field of view) and doesn't add additional weight to the aircraft, like traditional mechanical stabilizing systems. This research presents the implementation of a fisheye lens for aerial photography and mapping purposes, including theoretical background of fisheye lenses. Based on the unique feature of the distortion being a function of the viewing angle, methods used to derive the fisheye lens distortion are presented. The lens distortion is used to rectify the fisheye images before these images can be used in aerial photography. A detailed investigation into the inner orientation of the camera and inertial sensor is given, as well as the registration of airborne collected images. It was found that the attitude estimation is critical towards accurate mapping using low quality sensors. A loosely coupled EKF filter applied to the GPS and inertial sensor data estimated the attitude to an accuracy of 3-5° (1-sigma) using low-cost sensors typically found in small UAVs. However, the use of image stitching techniques may improve the outcome. On the other hand, lens distortion caused by the fisheye lens can be addressed by rectification techniques and removed to a sub-pixel level. Results of the process present image sequences gathered from a piloted aircraft demonstrating the achieved performance and potential applications towards UAVs. Further, an unforeseen issue with a vibrating part in the lens lead to the need for vibration compensation. The vibration could be estimated to ±1 pixel in 75% of the cases by applying an extended Hough transform to the fisheye images.

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27

Introvičová, Sabina. "Standardizace využití dálkového průzkumu Země pro potřeby Forenzní ekotechniky: les a dřeviny." Doctoral thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-234414.

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The thesis presents the main points of standardization of remote sensing (RS) usage for Forensic Ecotechnique: forest and trees (FEft). Based on the study FEft expertise database, the types of expertise, which remote sensing data have already been used and the types where the use of remote sensing increases the exactness of solutions were analyzed. RS data are essential in a problematic situation when an examined object does not exist or has been changed at the time of the assignment. This situation may be solved by obtaining information about the investigated object via retrospective image data, as described in the model example. There are chosen categories of image data relevant to the needs of experts in this thesis. These categories of RS data and their products are described with an indication of their possible use in the expertise processing, including freely available or paid resources and archives of image data.

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Buckley, Craig. "Photomosaicing and automatic topography generation from stereo aerial photography." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/790.

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Gombos, Andrew David. "DETECTION OF ROOF BOUNDARIES USING LIDAR DATA AND AERIAL PHOTOGRAPHY." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_theses/75.

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The recent growth in inexpensive laser scanning sensors has created entire fields of research aimed at processing this data. One application is determining the polygonal boundaries of roofs, as seen from an overhead view. The resulting building outlines have many commercial as well as military applications. My work in this area has created a segmentation algorithm where the descriptive features are computationally and theoretically simpler than previous methods. A support vector machine is used to segment data points using these features, and their use is not common for roof detection to date. Despite the simplicity of the feature calculations, the accuracy of our algorithm is similar to previous work. I also describe a basic polygonal extraction method, which is acceptable for basic roofs.

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30

Gifford, Eric Allan 1965. "Hough transform extraction of cartographic fiducial marks from aerial photography." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277903.

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Cartographic compilation requires precision mensuration. The calibration of mensuration processes is based on specific fiducials. External fiducials, around the exterior frame of the image, must be precisely measured to establish the overall physical geometry. Internal fiducials are provided within the image by placement of cloth panels on the ground at locations whose position is precisely known. Both types of fiducials must be known within the pixel space of a digitized image in order for the feature extraction process to be accurate with respect to delineated features. Precise mensuration of these fiducials requires that a cartographer view the image on a display and use pointing devices, such as a mouse, to pick the exact point. For accurate fiducial location, the required manual operations can be an added time-consuming task in the feature extraction process. Interactive tools which eliminate the precise pointing action for the operator are described in this thesis. The operator is required only to "box-in" the fiducial, using a simple drawing tool, select the fiducial function, and the software of the tool returns the precise location of the fiducial.

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31

Fu, Youtong. "Use Of Small Format Aerial Photography in NPS Pollution Control Applications." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/26346.

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An automated procedure was developed to identify and extract confined poultry facilities from color 35-mm slide imagery collected by the United States Department of Agriculture/Farm Service Agency (USDA/FSA). The imagery is used by the USDA/FSA to monitor compliance with various farm support programs and to determine crop production acreage within a given county. The imagery is generally available for all counties within the state on an annual basis. The imagery, however, is not flown to rigid specifications as flight height, direction, and overlap can vary significantly. The USDA/FSA attempts to collect imagery with reasonably clear skies, as visual interpretations could be drastically impacted by cloudiness. The goal of this study was to develop procedures to effectively utilize this imagery base to identify and extract poultry facilities using automated techniques based on image processing and GIS. The procedure involved pre-screening the slides to determine coverage, geopositioning to USGS quadrangle base, color scanning to convert slide image to a digital format and archiving each data file with a naming convention that would allow rapid retrieval in later analysis. Image processing techniques were developed for identifying poultry facilities based on spectral characteristics. GIS tools were used to select poultry facilities from an array of features with similar spectral characteristics. A training data set was selected from which the spectral characteristics of poultry facilities were analyzed and compared with background conditions. Poultry facilities were found to have distinguishable characteristics. Descriptive statistics were used to define the range of spectral characteristics encompassing poultry facilities. Thresholding analyses were then utilized to eliminate all image features with spectral characteristics outside of this range. Additional analyses were made to remove noise in the spectral image due to the sun angle, line of sight of camera, variation in roof reflectance due to rust and/or aging, shading by trees, etc. A primary objective in these analyses was to enhance the spectral characteristics for the poultry facility while, at the same time, retaining physical characteristics, i.e. the spectral characteristic is represented by a single blue color with a high brightness value. The techniques developed to achieve a single blue color involved the use of Principal Component Analysis (PCA) on the red color band followed by RGB to Hue and RGB to Saturation analyses on the red and green color bands, respectively, from the resulting image. The features remaining from this series of analyses were converted into polygons (shape file) using ArcView GIS, which was then used to calculate the area and perimeter of each polygon. The parameters utilized to describe the shape of a poultry house included width, length, compactness, length-width ratio, and polygon centroid analysis. Poultry facilities were found to have an average width of approximately 12.6m with a low standard deviation indicating that the widths of all houses were very similar. The length of poultry facilities ranged from 63m to 261m with and average length of 149m. The compactness parameter, which also is related to length and width, ranged from 30 to 130 with a mean value of approximately 57. The shape parameters were used by ArcView GIS to identify polygons that represent poultry facilities. The order of selection was found to be compactness followed by length-width ratio and polygon centroid analysis. A data set that included thirty 35-mm slide images randomly selected from the Rockingham County data set, which contained over 2000 slides, was used to evaluate the automated procedure. The slides contained 182 poultry houses previously identified through manual procedures. Seven facilities were missed and 175 were correctly identified. Ninety-seven percent (97%) of existing poultry facilities were correctly identified which compares favorably with the 97 % accuracy resulted by manual procedures. . The manual procedure described by Mostaghimi, et. al.(1999) only gave the center coordinates for each poultry facility. The automated procedure not only gives the center coordinate for each poultry building but also gives estimates for geometric parameters area, length and width along with an estimate of the capacity of building (i.e. number of birds), and waste load generated by birds including nutrient and bacteria content. The nutrient and bacteria load generated by each poultry facility is important information for conducting TMDL studies currently being developed for impaired Virginia streams. The information is expected to be very helpful to consultants and state agencies conducting the studies. Agricultural support agencies such as USDA/NRCS and USDA/FSA, Extension Service, consultants, etc. will find the information very helpful in the development of implementation plans designed to meet TMDL target water quality goals. The data also should be useful to Water Authorities for selection of appropriate treatment of water supplies and to county and local government jurisdictions for developing policies to minimize the degradation of water supplies.
Ph. D.

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Taylor, Jeremy. "Iron Age and Roman landscapes in the East Midlands : a case study in integrated survey." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/1566/.

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Millinor, William A. "Digital Vegetation Delineation on Scanned Orthorectified Aerial Photography of Petersburg National Battlefield." NCSU, 2000. http://www.lib.ncsu.edu/theses/available/etd-20001123-131211.

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I developed a new methodology to produce an orthorectified mosaic and a vegetation database of Petersburg National Battlefield using mostly digital methods. Both the mosaic and the database meet National Map Accuracy Standards and proved considerably faster than traditional aerial photograph interpretation methods. I classified vegetation polygons to the formation level using the Nature Conservancy?s National Vegetation Classification System. Urban areas were classified using Mitchell?s Classification Scheme for Urban Forest Mapping with Small-Scale Aerial Photographs. This method reduced the production time by 2/3, compared to traditional methods. It also reduced the chance of user error because re-tracing of the linework is not required.

My method started with scanning 75 aerial color IR photos, provided by Petersburg National Battlefield, at 600 dpi. Erdas Imagine was used to rectify the images using United States Geological Service (USGS) Digital Elevation Models (DEM) and black and white USGS Digital Orthophoto Quarter Quadrangles (DOQQ) as reference. The images were then mosaiced to create a seamless color infrared orthorectified basemap of the park. The vegetation polygons were drawn onscreen using ArcMap from Environmental Systems Research Institute, Inc. (ESRI) with the color, orthorectified mosaic as a background image. Stereo pairs of the aerial photos were referenced as needed for clarification of the vegetation. I used a minimum mapping unit (mmu) of 0.2 hectares, which exceeds guidelines defined by the United States Geological Survey ? National Park Service Vegetation Mapping Program. This methodology is easily learned quickly and has already been applied to several other studies.

The production of an orthorectified mosaic, created during the process, from the aerial photographs greatly increases the value of the photographs at little additional cost to the user. The orthorectified basemap can then be used as a backdrop for existing data layers or it can be used to create new GIS data layers. I used a minimum mapping unit (mmu) of 0.2 hectare, which exceeds guidelines defined by the United States Geological Survey-National Park Service Vegetation Mapping Program

Traditionally, vegetation polygons are delineated on acetate for each photograph. The linework on the acetates is then transferred to a basemap using a zoom transfer scope or other transfer instrument. The linework is traced again to digitize it for use in a GIS program. This process is time consuming, and the linework is drawn three times. The redundant tracing increases the chance of user error. My new methodology requires that polygons be delineated only once. I wanted to avoid using the zoom transfer scope and to avoid the redundant linework.

A total of 228 polygons were delineated over 20 separate vegetation and land cover classes with an overall thematic accuracy of 87.42% and a Kappa of .8545. Positional accuracy was very good with a RMSE of 1.62 meters in the x direction and 2.81 meters in the y direction. The Kappa and RMSE values compare favorably with accuracies obtained using traditional vegetation mapping methods.

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Deriu, Davide. "The photogenic city : aerial photography and urban visions in Europe, 1914-1945." Thesis, University College London (University of London), 2004. http://discovery.ucl.ac.uk/1446792/.

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The thesis investigates the relationship between photography and urban visions in Europe in the period 1914-1945. It focuses in particular on the impact of the aerial gaze upon the ways in which the modern city was perceived and represented. The theoretical background for this inquiry is provided by contemporary debates on photography and visual culture, which are brought to bear on the study of urban representations. The main body of the argument is divided into three parts: 'Aerial Inspections', 'Aerial Imaginations', and 'Aerial Illustrations'. The first part discusses the urban imagery produced within the field of air reconnaissance photography, with particular regard to World War II. The second part charts the rise of an aerial imagination in avant-garde photography, which reconfigured the city as the site and subject of a modern way of seeing. The third part looks at how 'applied' aerial photography was instrumental to illustrate urban visions across various discursive fields, namely tourism, journalism, and urbanism; this section concludes with a case study on the aerial imagery of interwar London, based on the production of a leading air survey company. Besides pinpointing the modes of representation specific to each of these practices, the thesis also describes the traffic of images and the flow of meanings that occurred across their boundaries. It is finally argued that a new urban visuality was the result of the procedures introduced by aerial photography: the photogenic city emerged as a contested field of representation marked out by an underlying tension between spectacle and surveillance.

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Demiraslan, Tugay. "Estimation of DBH Using Tree Variables Derived from Aerial LiDAR for Ford Forest, Baraga, Michigan." Thesis, Michigan Technological University, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13422276.

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This study implemented LiDAR (Light Detection and Ranging) remote sensing technology and applied ITD (Individual Tree Detection) methods as an approach to estimate some essential tree variables, such as DBH (Diameter at Breast Height), height, volume, and biomass for Ford Forest Research Center in Upper Peninsula, Michigan. There were 34 deciduous (1 bigtooth aspen, 9 red oaks, 20 sugar maples, 2 white birches, and 2 yellow birches) and 17 coniferous (2 eastern hemlocks, 11 red pines, and 4 white pines) subject tree species. There were two different available LiDAR datasets from the same area that were collected in 2011 and 2017. Height measurements were done at 96% and 97% accuracy for hardwood and softwood tree species, respectively.

Several other tree variables derived from LiDAR point cloud were used to estimate DBH by using regression analysis for both 2017 and 2011 datasets. Estimation equations were tested on the other dataset. The best-fitted formula was 2017’s, with 0.55 adjusted R² and less than 0.0001 p-values on 2017 LiDAR data while 0.42 adjusted R² and less than 0.0001 p-values on 2011’s dataset. Some additional analysis that includes calculating PRMSE (Predicted Root Mean Square Error), BIAS (Mean Error), and MAD (Mean Absolute Difference) have been applied. The equation that was generated by using data from 2017 has –0.57 BIAS for Hardwood and 1.13 BIAS for softwood. That result indicates that the equation has –0.57 centimeters (cm) estimation error for hardwood and 1.13 cm for softwood on DBH estimations.

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Brimicombe, A. J. "Uncertainty and fitness-for-use in handling aerial photographic interpretive data in geographical information systems." Thesis, Hong Kong : University of Hong Kong, 1994. http://sunzi.lib.hku.hk/hkuto/record.jsp?B14394820.

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Valinger, John. "Automatic rooftop segment extraction using point clouds generated from aerial high resolution photography." Thesis, Umeå universitet, Institutionen för datavetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-119123.

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Automatically extracting rooftop information from aerial photographs using point cloud generations tools and point cloud plane segmentation algorithms is a interesting and challenging topic. Previous studies on rooftop extraction have used airborne Light Detection And Ranging (LiDAR) derived point clouds or point clouds generated from photographs taken specifically for point cloud generation. We have used photographs taken from the Swedish National Land Survey database to generate point clouds using stereo-matching for rooftop segmentation. Aerial imagery from this data is both cheap and has nationwide coverage. Point cloud generation tools are evaluated based on coverage, point cloud size, geographical precision and point density. We propose a novel combination of property map clipping and rooftop plane segmentation algorithms derived from aerial photography via point cloud generation after comparing promising segmentation algorithms. We conclude that the point clouds generated from the aerial imagery are not sufficient for the implemented method for completely extracting all rooftop segments on a building in an urban environment.

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Niu, Xutong. "Highway extraction from high resolution aerial photography using a geometric active contour model." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1101833084.

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Meadows, P. L. "The applications of aerial photography, photogrammetry and photo-interpretation in the planning process." Master's thesis, Faculty of Engineering and the Built Environment, 2021. http://hdl.handle.net/11427/33400.

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To date aerial photography and associated photogrammetric and photo-interpretation techniques have played but a limited role in the planning process. In this study their dual role (i) as a base medium and (ii) as a source of data is investigated bearing in mind the requirements of planning data and certain inherent defects of conventional maps in the planning process. Having considered certain pertinent technical aspects of aerial photography and associated techniques, especially modern developments such as orthophotos, use of multi-emulsion photography, automated data extraction and automated data processing techniques, the application of these techniques is discussed in greater detail in respect of the dual role mentioned earlier. Aerial photographs are shown to be of considerable value to the planner as an analytic tool and a powerful source of data when dealing with such topics as feasibility studies, land use, resource surveys, urban and regional research and analysis, urban history, urban and rural administration, site evaluation, transportation and other. branches of engineering, urban sociology and economics, as well as urban aesthetics. Aerial photographic data adequately meets the data requirements of the planning process and furthermore lends itself to modern automatic data processing methods. The modern improved forms of photography, i.e. photomaps, orthophotos, etc. have definite advantages over conventional maps insofar as a base medium in planning is concerned, and the wider use of aerial photographs and products is anticipated when planners become more aware of their universal application and versatility.

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Knapp, Paul Aaron. "THE USE OF LARGE-SCALE AERIAL PHOTOGRAPHY FOR DETECTING CHANGES OF AN ARID RANGELAND IN SOUTHWESTERN ARIZONA." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/292059.

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Interpretation of large-scale color infrared and color aerial photography can be a labor and cost-effective means for inventorying and monitoring rangelands while maintaining accuracy. Ground measurements of vegetation cover at Organ Pipe Cactus National Monument were taken in 1975 and 1984. Large-scale (1:1200) color and color infrared aerial photo estimates were compared to these ground measurements through regression and correlation to check photo accuracy. Relationships between photo estimates and ground measurements of total vegetation and shrub cover were strong when using either film type. Color infrared photo estimates corresponded better with ground measurements for both tree cover and cactus cover than color photo estimates. Large-scale aerial photography is also useful for determining some of the causes of vegetation change. Evidence gathered from both sets of photos suggested that vegetation change at OPCNM was largely the result of domestic livestock removal and short-term climatic fluctuations.

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Edwards, Esther. "An investigation into the use of aerial digital photography for monitoring coastal sand dunes." Thesis, Bath Spa University, 2001. http://researchspace.bathspa.ac.uk/1442/.

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The coastal zone is a highly dynamic entity both spatially and temporally and when shoreline changes (and in particular retreat) occur on a hmnan time-scale, measurement of the rate of change becomes a pressing issue. This dynamism presents an excellent scenario for monitoring change using remote sensing techniques, and in the case of coastal sand dunes, where the requirement is to measure small scale changes such as erosion or accretion in the region of 10 or 20 m, aerial photography is the preferred source of remotely sensed data. The rapid developments in digital camera technology and real time satellite differential Global Positioning Systems have yielded new opportunities for mapping and monitoring environmental change when used with image processing and mapping software and state-of-the-art digital photogrammetric workstations. Despite the progress in digital technologies, however, there is still considerable lack of awareness on the part of potential users, and it is in response to this that the processing chain for data collection through to orthophoto production described here has been developed. This study explores the major issues that affect quality, mission logistics and cost and will demonstrate the methodology and application of digital techniques for producing georectified imagery and contoured orthophoto maps of coastal environments. This will be achieved through a series of case studies of dynamic dune environments in south-west England and France. Digital imagery was captured using a colour infrared Aerial Digital Photographic System and ground control was collected using differential Global Positioning Systems. This study seeks to assess the application of this imagery to coastal dune monitoring, putting these new techniques within the grasp of coastal dune managers, enabling them to make use of digital imagery captured to different specifications depending on the accuracy requirement of the end product. The results indicate that this type of imagery and the techniques used can provide the dune manager with information which would otherwise be too costly or time consuming to acquire. 2D rectification of the imagery provided maps of dune retreat and accretion with errors in the region of± 1.5m, and rectification to a higher order using 3D photogrammetric correction provided 1 :5000 contoured orthophotographs with mean xy errors in the region of 2. 5 m and mean elevation errors in the region of 1.5m.

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Park, Keith Marron. "The global-to-local search method: A systematic search procedure that uses the context of the textured layout to locate and detect low-contrast targets in aerial images." CSUSB ScholarWorks, 1993. https://scholarworks.lib.csusb.edu/etd-project/700.

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Smith, Scott R. "Aerial perspective and geography : an historical look at the use of aircraft to gain a sense of place /." Abstract Full Text (HTML) Full Text (PDF), 2009. http://eprints.ccsu.edu/archive/00000575/02/2016FT.htm.

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Thesis (M.S.) -- Central Connecticut State University, 2009.
Thesis advisor: Cynthis Pope. "... in partial fulfillment of the requirements for the degree of Master of Science in Geography." Includes bibliographical references (leaves 77-81). Also available via the World Wide Web.

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Baxter, Kieran Andrew. "Topography and flight : the creative application of aerial photography and digital visualisation for landscape heritage." Thesis, University of Dundee, 2017. https://discovery.dundee.ac.uk/en/studentTheses/e22373db-adee-4bb1-9fbe-43691816ce85.

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Aerial photography and digital visualisation technologies are commonly used to reveal and interpret archaeological sites and landscapes. These methods afford a clarity and overview that has considerable advantages in heritage visualisation. Despite this, both technologies offer a view that is distanced from the grounded experiences that are integral to heritage sites and landscapes. This tension, between visualisation technologies and lived experience, is significant because the experiences of visiting these places are a valuable common platform - shared by specialists and general audiences alike - for communicating archaeological narratives. Beyond this, such tensions have been central to debates within landscape archaeology about how embodied perspectives on the one hand, and the conventions of visual representation on the other, might affect archaeological interpretations. This thesis investigates the hypothesis that creative practice can serve to bridge the gap between visualisation technologies and lived experience, ultimately providing more powerful and meaningful visualisations of landscape heritage. This is possible because aerial and digital visualisations can and do go beyond topographical representation and respond to the aesthetic and emotive dimensions of landscape. Aerial photographs and digital models resist the visual modes of modernity despite their technological premise. The meanings that they transmit draw not only from the visual language of aerial photography and digital media but also from the viewer's prior experience of landscape and flight. It is within this context that this study attempts to better understand the relationship between visualisation technologies, creative practice, and the lived experience of landscape. To do this the author adopts the role of research-practitioner in order to explore and demonstrate the arguments through the creative application of aerial photography and digital visualisation technologies. This practice combines methods from archaeological survey, and approaches from visual effects filmmaking, with an aesthetic inspired by artist-photographers like Marilyn Bridges, Emmet Gowin and Patricia Macdonald. These creative practitioners have adopted the aerial view to portray landscapes with intimacy, agency and dynamism. The practice aims to work from an immersed or insider's view, drawing influence from Tim Ingold's notion of the "dwelling perspective". A main case study is undertaken at the Iron Age hillfort site of the Caterthuns in Angus, Scotland, with supporting case studies at the prehistoric site of Links of Notlland in Orkney and additional hillfort sites in Strathearn. Through this hands-on experience the aim is to better understand how novel approaches to practice can improve landscape heritage visualisation in an interdisciplinary context.

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Kunz, Matthias. "Elevation changes of mountain glaciers in the Antarctic Peninsula using ASTER-controlled archival aerial photography." Thesis, University of Newcastle upon Tyne, 2014. http://hdl.handle.net/10443/2392.

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Over the last 50 years a significant increase in the atmospheric and upper ocean temperatures in the Antarctic Peninsula (AP) region has been observed. As a result major ice-shelves have retreated during the 20th century. In connection, glaciers have accelerated and an increased dynamic ice mass loss is observed, especially over the last decade. Despite these major changes, an exact quantification of ice mass changes of the AP, with its roughly 1000 glaciers, is not available. Almost no long-term (multi-decadal) glacier mass balance records for the AP exist and in-situ measurements are rare. On the other hand, the United States Geological Survey (USGS) and British Antarctic Survey (BAS) archives hold a large number of historic aerial stereo-photographs of the AP, dating back to the early 1940s. These images contain a valuable source of information and have been used to demonstrate widespread retreat of glaciers in this region. Less effort has been made so far to use this stereo-photography for the extraction of elevation data to compare it with recent elevation information to determine glacier volume change from which mass changes may be estimated. This dissertation seeks to close this research gap and to extend the number of mass balance records for the AP, by investigating, measuring, and analysing historical glacier elevation change in the AP using digital elevation models (DEMs) derived from USGS and BAS airborne (1948-2005) and ASTER spaceborne (2001-2010) stereo imagery. To ensure reliable and accurate measurements of surface elevation change, extracted DEMs need to be registered in a precise manner. The lack of ground control information in the AP is a major obstacle for this and can result in inaccurate absolute orientations of DEMs. If uncorrected, possible offsets between DEMs introduce significant error and i can lead to an over- or underestimation of glacier change. Thus, in order to precisely co-register corresponding historic and modern DEMs an iterative robust least squares surface matching algorithm was applied. The underlying surface matching approach was previously developed for small-scale coastal erosion studies at Newcastle University. Within the context of this work it has been successfully modified and improved to enable large scale glacier change assessment in areas of steep topography which is typical for the AP. For a total of 12 glaciers in the AP, located along the western coast between 64° and 71° S, DEMs from the historic archive stereo-imagery were successfully extracted and combined with DEMs derived from modern aerial and ASTER satellite imagery. The improved surface matching approach allowed precise co-registration of these DEMs and enabled the accurate measurement of glacier surface mass balance at the lower portion of the glaciers. Widespread frontal glacier surface lowering, of up to 50 m, has been observed on 12 glaciers with a mean lowering rate of 0.28 ± 0.03 m/yr over a period of 37 years (1970-2007). Higher rates, of up to 0.6 m/yr, were observed in the north-western Peninsula. Two glaciers which have multi-epoch coverage show a significantly larger-than-average lowering since about 1990. These results are in close correspondence with an increase in positive degree days over the last four decades and suggest that much of this lowering can be attributed to atmospheric forcing. However, the observed spatial and temporal variations in the lowering rates suggests that the pattern of surface change is not a simple one and that a regional upscaling is not straight forward. The glaciers represent only 1.2 % of all estimated glaciers in the AP and only the glacier fronts (~20 % of each glacier) were studied. Observations also show an elevation increase at some higher altitude locations within a few km of the glacier fronts, raising the potential that the lowering may have been at least partially compensated for by increased high-altitude accumulation.

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Fyfield, Paul Hagen. "Transportation and Land Use Patterns: Monitoring Urban Change Using Aerial Photography, Portland, Oregon 1925-1945." PDXScholar, 2003. https://pdxscholar.library.pdx.edu/open_access_etds/2242.

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American urban neighborhoods are a patchwork; the spatial arrangement of types is a reflection of the dominant transportation technology at the time of their development. The earliest suburban areas were made accessible by fixed route systems such as the electric streetcar, followed by the widespread adoption of the automobile; each transportation epoch resulted in characteristic patterns of land use. This study uses aerial photographic coverage of Portland, Oregon from the years 1925, 1936, and 1945, a time of decline for the once popular trolley lines and dramatic increase in automobile usage, to monitor change within the residential areas of Portland's east side over a twenty year period. Classic economic models of the time acknowledged transportation as a force shaping the city; modem ideas in urban planning such as Traditional Neighborhood Design and Transit Oriented Development look to pre-automobile urban form as a means to reduce automobile use and its negative implications. This study uses variables of housing density and street connectivity derived from the aerial photography; the measured values of these variables are then considered for their spatial and temporal distribution using statistical comparisons. The results are compared to ideas within the urban models and current thinking about urban morphology. While generally consistent with the expected patterns, deviations and differences between the two variables are considered for their implications. Models offer a simplified version of the growth of American cities, considering only a few of the many aspects of a dynamic environment. By isolating on these variables of density and connectivity, a greater understanding of their role in arriving at the modem residential urban environment may be reached, and this understanding can add to the discourse in current planning debates.

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Dicks, Steven E. "Satellite-derived surface temperatures and their relationships to land cover, land use, soils and physiography of North-Central Florida." Gainesville, FL, 1986. http://www.archive.org/details/satellitederived00dick.

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Wilhite, Jerry W. "Use of infrared aerial photographs to identify and assess habitat needed by native fish in rivers." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1445041571&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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Wolters, Dustin Joseph. "Assessment of Corn Plant Population at Emergence from Processed Color Aerial Imagery." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1437666741.

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Rosenberg, Abigail Stella. "An Evaluation of a UAV Guidance System with Consumer Grade GPS Receivers." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194506.

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Remote sensing has been demonstrated an important tool in agricultural and natural resource management and research applications, however there are limitations that exist with traditional platforms (i.e., hand held sensors, linear moves, vehicle mounted, airplanes, remotely piloted vehicles (RPVs), unmanned aerial vehicles (UAVs) and satellites). Rapid technological advances in electronics, computers, software applications, and the aerospace industry have dramatically reduced the cost and increased the availability of remote sensing technologies.Remote sensing imagery vary in spectral, spatial, and temporal resolutions and are available from numerous providers. Appendix A presented results of a test project that acquired high-resolution aerial photography with a RPV to map the boundary of a 0.42 km2 fire area. The project mapped the boundaries of the fire area from a mosaic of the aerial images collected and compared this with ground-based measurements. The project achieved a 92.4% correlation between the aerial assessment and the ground truth data.Appendix B used multi-objective analysis to quantitatively assess the tradeoffs between different sensor platform attributes to identify the best overall technology. Experts were surveyed to identify the best overall technology at three different pixel sizes.Appendix C evaluated the positional accuracy of a relatively low cost UAV designed for high resolution remote sensing of small areas in order to determine the positional accuracy of sensor readings. The study evaluated the accuracy and uncertainty of a UAV flight route with respect to the programmed waypoints and of the UAV's GPS position, respectively. In addition, the potential displacement of sensor data was evaluated based on (1) GPS measurements on board the aircraft and (2) the autopilot's circuit board with 3-axis gyros and accelerometers (i.e., roll, pitch, and yaw). The accuracies were estimated based on a 95% confidence interval or similar methods. The accuracy achieved in the second and third manuscripts demonstrates that reasonably priced, high resolution remote sensing via RPVs and UAVs is practical for agriculture and natural resource professionals.

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Dissertations / Theses on the topic 'Aerial photography in forestry'

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