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3D Shape Reconstruction from Multiple Range Image ViewsGanapathi Annadurai, Kartick January 2006 (has links)
Shape reconstruction of different three dimensional objects using multiple range images has evolved recently within the recent past. In this research shape reconstruction of a three dimensional object using multiple range image views is investigated. Range images were captured using the Waikato Range Imager. This range images camera is novel in that it uses heterodyne imaging and is capable of acquiring range images with precision less than a millimeter simultaneously over a full field. Multiple views of small objects were taken and the FastRBF was explored as a mean of registration and surface rendering. For comparison to the real range data, simulated range data under noise free condition were also generated and reconstructed with the FastRBF tool box. The registration and reconstruction of simple object was performed using different views with the FastRBF toolbox. Analysis of the registration process showed that the translation error produced due to distortion during registration of different views hinders the process of reconstructing a complete surface. While analyzing the shape reconstruction using the FastRBF tool it is also determined that a small change in accuracy values can affect the interpolation drastically. Results of reconstruction of a real 3D object from multiple views are shown.
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Selection of day roosts by female long-legged myotis (Myotis volans) in forests of the central Oregon CascadesOrmsbee, Patricia 09 February 1996 (has links)
Measuring habitat selection by bats is complicated by their intricate life cycle. Scaling habitat measurements to reflect a hierarchal habitat selection process can help to define habitat associations of bats. I assessed day roost habitat of female long-legged myotis at four scales: the roost structure, micro-habitat surrounding the roost, the stand level, and landscape level.
I radio-tracked 16 female long-legged myotis (Myotis volans) for an average of eight days per bat, July through August of 1993, 1994, and 1995 in two drainages in the central Oregon Cascades (Quentin Creek and Lookout Creek) to locate day roost structures. Forty-one day roost structures were identified, of which 1 was a rock face, 4 were green trees, and 36 were snags. The average height of all roost structures was 40 m (SE=2.5). The average dbh for all snags and trees used as day roosts was 100 cm (SE=6.1). Large snags including partially live, hollow western redcedar trees (Thuja plicata) averaging 97 cm dbh (SE=6.6) and 38 m (SE=2.8) high were the most commonly used roost structures.
Individuals radio-marked at the same night roost did not use one common day roost.
Individual bats were found roosting in one roost for several days, or using multiple day roosts within discrete roost areas. The area which encompassed one night roost
and all known day roosts covered 3,258 ha in the Quentin Creek drainage and 6,391 ha in Lookout Creek.
I compared physical characteristics and habitat within 20 meters of 33 roost snags with 66 randomly selected snags. The odds that a snag is used as a day roost is associated with roost height; given height, the odds of use is associated with the height of the stand within 20 meters of the snag. There is some indication that the presence of an open canopy around the snag, and the percentage of bark on the snag also could be factors that influence the selection of snags as day roosts.
The frequency of occurrence of roost structures within young and late seral stands did not differ from what was expected to occur by chance in these two stand conditions. Roosts did not occur in stands with a harvest history vs. stands without a harvest history disproportionate to availability.
I compared the distance to class I (largest) through class IV (smallest) streams between 34 day roosts and 102 randomly selected points. Day roosts were located closer to streams than randomly selected locations in both Lookout and Quentin Creek drainages with 1 exception (Lookout class III). In two cases day roosts were significantly closer to streams than randomly selected locations. Day roosts tended to be closer to streams where night roosts were located than did randomly selected points, regardless of stream class. / Graduation date: 1997
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Canopy epiphyte studies in the central Oregon Cascades : implications for the management of Douglas-fir forestsSillett, Stephen Charles 22 November 1995 (has links)
This thesis includes four separate studies. The first two studies assessed edge effects in a
700-year-old forest. After 20 years of exposure, epiphyte assemblages on the clearcut edge
were similar to those of the forest interior, but there were some differences in vertical
distribution patterns. Several species restricted to the upper canopy of the forest interior
occurred farther down in the crowns of trees on the clearcut edge. Many species were
associated with thick moss mats. Thalli of two cyanolichen species were reciprocally
transplanted among four tree crowns. Lobaria oregana grew less on the clearcut edge than
in the forest interior. Populations of Pseudocyphellaria rainierensis had acclimated to the
edge environment. The third study evaluated whether these two species require old growth
and/or thick, underlying moss mats to achieve normal rates of growth and mortality. Thalli
were transplanted into tree crowns in 13 forest stands representing 4 age classes: old
growth, mature, young, and recent clearcut. Wooden racks were used instead of trees in
clearcuts. Half of the cyanolichen thalli were transplanted onto thick moss mats, half onto
bare bark. Both species grew at least as well in the younger forests as they did in old
growth, but growth rates were significantly lower in clearcuts. Mortality rates were very
low in young, mature, and old-growth forests but high in clearcuts. P. rainierensis grew
significantly better on moss than bare bark. The fourth study evaluated the long-term
potential of live tree retention for cyanolichen conservation. Lichen litterfall was sampled
in a natural, multiple-age stand containing remnant trees and regenerating forest. Two
lichen species (L. oregana and Sphaerophorus globosus) were strongly associated with
remnant trees. Biomass of both species was highest near remnant trees and was
significantly higher within groves of remnant trees than at the edges of these groves or near
isolated trees. Cyanolichen populations appear to have persisted on remnant trees since
before the last fire. They are slowly recolonizing the regenerating forest. Retention of live
trees, including hardwoods, combined with longer rotation periods, has great potential to
maintain cyanolichens in managed forests. / Graduation date: 1996
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Object avoidance and wall following using the KinectSchwab, Carl William 24 February 2012 (has links)
The range camera in Microsoft's Kinect, intended for the Xbox 360 gaming console, offers a powerful alternative to the many standard sensors used in robotics for gathering spatial information about a robot’s surroundings. The recently-released Kinect is the first commercially available product to provide depth data of its resolution and accuracy with a price tag within reach of many robotics projects.
The work described in this paper explores the feasibility of using this sensor by developing a robot that relies solely on the Kinect for sensory data. This robot successfully performs standard navigational procedures, demonstrating the possibility of integrating spatial information from the Kinect into a real-time robotics application. This paper documents the techniques used to integrate the Kinect into the system, highlighting the key benefits and limitations of the sensor. / text
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Transitional tectonics : early Laramide strike-slip deformation of the Northeastern Front Range, ColoradoWharton, Goodwin Christopher 20 July 2012 (has links)
The early Laramide tectonic history and Proterozoic metamorphic history of the northeastern Colorado Front Range were examined using kinematic data from minor faults at 25 locations, and U-Th/He dating of apatite from 2 samples (3 unsuccessful) supported by optical petrography, X-ray maps and geothermometry.
The role of strike-slip faulting in Laramide uplift of the eastern flank of the northern Front Range was analyzed through kinematic analysis of 97 minor (<100 m trace) faults. The dominant fault population was oriented approximately perpendicular to bedding, with lineations sub-parallel to bedding. Rotating bedding to horizontal showed these faults to have the pattern of a strike-slip conjugate set.
Unfolded left-lateral faults have an average orientation of (287, 87N) with lineations to (287, 01); right-lateral faults have an orientation of (065, 88S) with lineations to (245, 00). The timing of motion on these faults postdates 98 Ma deposition of Dakota group sandstones, and predates the folds that rotated them (68 Ma from the age of synorogenic conglomerates). The conclusion is that strike-slip motion was active during the earliest Laramide.
The principal strain axes from these faults, after rotation, give an average shortening axis orientation of (276, 03) and an average extension direction of (006, 02). The calculated shortening axis orientation is consistent with that of later Laramide deformation, supporting the hypothesis that strike-slip deformation occurred in the northeast Front Range during the earliest Laramide.
Analysis of minor faults on part of the eastern flank of the northern Front Range shows that strike-slip faulting was a locally important deformation mechanism at the onset of the Laramide orogeny. Principal strain axis analysis suggests that the regional tectonic regime was one of east-west shortening and north-south extension prior to the onset of the main phase of Laramide deformation, at which time the regional strain field rotated to one of east-west shortening and vertical extension.
Twenty-seven thin-sections of Big Thompson Canyon metapelites were petrologically characterized prior to selection for mineral separation and U-Th/He analysis of apatite. All samples show late high-temperature static recrystallization that has partially recovered prior fabrics. At high grades, sillimanite porphyroblasts overgrow all fabrics. X-ray maps and geothermometry were also conducted to enhance the characterization of the sample suite. Garnet-biotite phase equilibria indicate that initial prograde metamorphism took place at approximately 550 °C.
Apatites separated from five of the twenty-seven samples analyzed in thin section were analyzed for U-Th/He thermochronometry. Three samples returned no plausible results; one sample returned one plausible age; and one sample returned three similar and plausible ages. Basement rocks cooled through the closure temperatures for helium and fission-tracks in apatite nearly simultaneously, at about 55 Ma. These temperatures, 40 and 60 °C respectively, correspond to depths of ~ 1.5 and 2.5 km. Laramide exhumation of the Northern Front Range was very rapid. Estimates of minimum magnitude of exhumation during Laramide time may need to be increased from ~2 km to ~3 km. / text
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Impacts of modernization on nomads and their use of rangeland resources in At-Taysiyah region, Saudi ArabiaAl-Haratani, Eisa Ramadan, 1958- January 1997 (has links)
Pastoral nomadism in arid and semiarid regions has evolved over many centuries as a rational response to uncertain climatic conditions and fragile ecosystems. Nomads are the main inhabitants of the bast area of marginal rangeland in Saudi Arabia. However, in the past few decades, modernization, in the form of improved transportation and access to water, combined with government subsidy of supplemental barley to the nomads of regions such as At-Taisyiah in the northern part of Saudi Arabia have provided the nomadic tribes with a buffer against uncertain climatic conditions and against the consequences of increasingly aggressive grazing of the range. In this study, an integrated approach is adopted to assess the impact of modernization and government intervention on the nomads and on the health of rangelands in At-Taisyiah. The approach consisted of interview with nomads in the region, a socio economic study of the region's nomadic lifestyle, analyses of several range capability assessment studies, and utilization of stochastic simulation models. Three major areas were identified in need of major improvements. These are the nomads' perception of range land resources, use of rangeland, and government policies towards nomads and rangeland. Improvement in these areas will play a major role in slowing the acceleration of desertification of marginal range lands in Saudi Arabia. comparison of Monte-Carlo simulations of four different grazing intensity scenarios and 12 different levels of government subsidies confirmed that lower grazing intensities provide the only means for sustainable utilization and for the combating of desertification of the rangelands in At-Taisyiah region.
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Nutrient contents of three Atriplex species (Atriplex cancensces, atriplex linearis and Atriplex polycarpa) under different management practices and site conditionsMehramiz, Mohammad Reza January 1998 (has links)
There are thousands hectares of abandoned farmlands in Arizona. Research on practical methods for establishing native plants and wildlife on abandoned farmlands is under way at the Desert Botanical Garden of Phoenix and the University of Arizona. This research is aimed at improving understanding of the primary variables affecting restoration of abandoned farmlands. These variables include: water treatments, planting dates, mulch and water catchment, seasonal planting and plant species composition. The objectives of the study is to investigate the effect of land restoration practices on nitrogen, protein, fiber (NDF and ADF), ash and dry matter contents of three Atriplex species under different management and site conditions. The amount of nutrient contents in Atriplex species growing on abandoned farmlands under irrigation and conservation practices is higher when compared to no irrigation or control in Casa Grande research site. Atriplex species growing under mulch and water catchment condition had significantly higher nutrient content compared to other treatments. Furthermore, seasonal planting in abandoned farmlands affected the nutrient contents of Atriplex cultivars at the University of Arizona farm. The Atriplex cultivar planted in the winter had higher nutrient contents when compared to those planted in the summer and irrigated with a sprinkler irrigation system for some cultivars. A better understanding of how these variables affect nutrient contents of Atriplex species used in this restoration study will play an important role in directing public interest towards the revegetation of abandoned farmlands in southern Arizona for food production.
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Establishment of native Atriplex species evaluated under a line-source sprinkler irrigation system during the summer and winterWatson, Mary Carolyn, 1949- January 1999 (has links)
Atriplex canescens (Pursh) Nutt., Atriplex polycarpa (Torr.) Wats., and Atriplex lentiformis (Torr). Wats. have been considered candidate perennial shrubs for revegetation of abandoned farmlands in southern Arizona. Objectives of the 1992-1994 field studies were to investigate the establishment characteristics of populations of these species and to estimate water requirements for establishing transplants and/or seedlings under a line-source sprinkler irrigation system. During the summer on a sandy loam soil, seedling establishment occurred at total water amounts greater than 200 mm but was absent at amounts less than 150 mm The poor stand establishment was attributed to high soil temperatures at 1 to 3-cm depth which were not optimum for seed germination. Transplant survival percentages were greater than 89% except for accessions of A. canescens var. linearis (S. Wats.) Munz, which were affected by rabbit herbivory. Transplants were successfully established by planting into a wet soil profile followed by cumulative precipitation amounts of 60 to 70-mm. Establishing Atriplex taxa during the summer using transplants was more promising than direct-seeding. On a silt loam soil during the 1993 winter, stand establishment was not increased under cumulative precipitation and irrigation amounts greater than 100 mm compared to 66 mm of precipitation. On a clay loam soil during the 1994 winter, supplemental irrigations increased the probability of seedling emergence and stand establishment was higher under total water amounts greater than 100 mm. Differences between years in response to the line-source irrigation gradient were attributed to the number of consecutive days when soil moisture at 1 to 3-m depth was high for optimal seedling emergence. During the winter, plant heights were not affected by total water amounts between 182 to 248-mm (1993) and between 119 to 150-mm (1994), whereas heights were reduced at total water amounts less than 100 nun in 1993, and less than 90 mm for all species in 1994 except A. polycarpa. In southern Arizona where precipitation is erratic in amount and timing, supplemental irrigations may increase the probability of successful seedling establishment of Atriplex shrubs.
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Effects of fire on Agave palmeriJohnson, Roxane Jeannette January 2001 (has links)
I investigated the effects of prescribed fire on Agave palmeri , an important seasonal food source of the federally Endangered bat, Leptonycteris curasoae yerbabuenae. Three different treatments were randomly assigned to plots containing agaves within a burn unit: plots were burned with extant fuel, plots were left unburned, and plots were burned with an augmentation of fuel. Agaves were surveyed before the fires, immediately after the fires, and one and two years after the fires. Mortality and survivorship with the fuel load, agave size and the type of clusters in which the agaves grew. Agaves near mesquite and acacia trees or dead, dried agaves experienced higher mortality than agaves growing elsewhere. Agaves in plots with added fine fuels also had higher rates of mortality. One year post-fire, mortality was low in all treatments and recruitment was higher on augmented and burned plots than on unburned plots. Two years post-fire, mortality of small Agave palmeri was associated more strongly with rainfall than with fire treatment, while mortality of larger height classes of agaves exhibited a delayed response to fires.
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Management of Range BullsBarnes, G. W. 09 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
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