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In this thesis, multiple ground target tracking algorithms are studied. From different aspects of the ground target tracking, three different types of tracking algorithms are proposed according to the specialties of the ground target motion and sensors employed. Firstly, the dependent target tracking for ground targets is studied. State dependency is a common assumption in traditional target tracking algorithms, while this may not be the true in ground target tracking as the motion of targets are constraint to certain path. To enhance the tracking algorithm for ground targets, starting with the dependency assumption, Markov Random Field (MRF) based Probabilistic Data Association (PDA) approach is derived to associate motion dependent targets. The driving behavior model is introduced to describe motion relationship among targets. The Posterior Cramer-Rao Lower Bound (PCRLB) is derived for this new motion model. Experiments and simulations show that the proposed algorithm can reduce the false associations and improve the predictions. Eventually, the proposed approach alleviates issues like the track impurity and coalescence problem and achieves better performance comparing to standard trackers assuming state independence. Ground target tracking using cameras is then studied. To build an efficient multi- target visual tracking algorithm, fast single target visual tracking is an important component. A novel visual tracking algorithm that has high speed and better or comparable performance to state-of-the-art trackers is proposed. The proposed approach solves the tracking task by using a mixed-motion proposal based particle filter with Ridge Regression observation likelihood calculation. This approach largely reduces the exhaustive searching in common state-of-art trackers while maintains efficient representation of the target appearance change. Experiments on 100 public benchmark videos, as well as a high frame rate benchmark, are carried out to compare the performance with the state-of-art published algorithms. The results of the experiment show the proposed tracker achieves good performance while beats other algorithms in speed with a large margin. The proposed visual target tracker is integrated into a new multiple ground tar- get tracking algorithm using a single camera. The multi-target tracker addresses the issues in the target detection, data association and track management aside from the single target tracker. A perspective aware detection algorithm utilizing the re- cent advanced Convolutional Neural Networks (CNN) based detector is proposed to detect multiple ground targets and alleviate the weakness of CNN detectors in detecting small objects. A hierarchical class tree based multi-class data association is presented to solve the multi-class association problem with potential misclassified detections. Track management is also improved utilizing the high efficiency detectors and a Support Vector Machine (SVM) based track deletion is proposed to correctly remove the dead tracks. Benchmarking is presented in experiments and results are analyzed. A case study of applying the proposed algorithm is provided demonstrating the usefulness in real applications. / Thesis / Doctor of Philosophy (PhD)

This thesis analyzes the effectiveness of spatially averaged Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements at regular azimuth angle intervals on an hourly basis to validate satellite based DOAS measurements. Off-Axis MAX-DOAS Measurements taken in Blacksburg, Virginia, between November 2021 and April 2022 with an evenly distributed set of measurements were averaged every hour and compared to Direct Sun measurements, also averaged every hour. Comparisons of the difference in average measurement from both measuring strategies, as well as the distribution standard deviations of hourly measurements suggests that the NO₂ distribution around Blacksburg is homogeneous. In order to test the effectiveness of this sampling strategy,in an inhomogeneous location, the LOTOS-EUROS high resolution (1kmx1km) chemical transport model was used to simulate profiles and vertical column densities of real measurements taken during the TROLIX'19 Field Campaign. The LOTOs-EUROS model was used to simulate vertical profiles as well as Vertical Column Densities based on real MAX-DOAS measurements as well as TROPOMI viewing geometry. While the individual ground measurements were not equal to the TROPOMI profile, the TROPOMI profile is approximately the average of the profiles of measurements made within the hour of TROPOMI overpass. / M.S. / This thesis analyzes the effectiveness of spatially averaged Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements at regular intervals of angles offset from due North on an hourly basis to validate satellite based DOAS measurements. MAX-DOAS Measurements taken relative to the position of the sun in Blacksburg, Virginia, a low NO₂ location, between November 2021 and April 2022 to determine the effectiveness of a generalized measuring strategy for satellite validation in low pollution environments. An evenly distributed set of measurements were averaged every hour and compared to measurements taken in the direction of the sun, also averaged every hour, to determine if the variability of NO₂ around Blacksburg is high enough to require a generalized sampling strategy, or if the NO₂ distribution is homogeneous enough to be accurately validated with Direct Sun measurements only.. Comparisons of the difference in average measurement from both measuring strategies, as well as the distribution of standard deviations of hourly measurements suggests that the NO₂ distribution around Blacksburg is low. In order to test the effectiveness of this sampling strategy in a higher pollution location with many sources and sinks of NO₂, the data from the LOTOS-EUROS high resolution (1kmx1km) chemical transport model run by the Royal Dutch Meteorological Institute for the TROLIX'19 Field Campaign was used to simulate vertical distributions of NO₂ and vertical column densities of measurements taken during the field campaign. The LOTOS-EUROS model was used to simulate vertical distributions of NO₂ as well as Vertical Column Densities based on real MAX-DOAS measurements as well as viewing geometry seen by the TROPOspheric Monitoring Instrument (TROPOMI) satellite-based instrument. While the individual ground measurements were not equal to the vertical distribution seen by TROPOMI, the TROPOMI vertical distribution is approximately the average of the vertical distributions of measurements made within an hour of TROPOMI passing over Rotterdam.

Ground, construction, light and weather: all of these elements when compounded create architecture. What is the built? What is the unbuilt? How can we merge the two? How can we architect a future where buildings are so contextually true to their site that the boundary of what was traditionally exterior and interior are one in the same? A building must be rooted in the site, it must be of the ground. It has to be grounded. The roots of the building must dig deep into the meaning of what the site is, what it was, and what it wants to be. Through careful discernment of these varied layers of ground are, we can begin to understand the levels and layers that take place within a structure. This thesis strives to ground architecture. The library at Rock Creek Park is nestled into the site, it is of the site, and honest to the site. A building that seems to grow out of Rock Creek Park as it exists in a city, a building that pulls the park into the city, and the city into the park. It is a glimpse of what potential the futures can hold if we, as designers, decide to collaborate, to treat each discipline as a layer of groundwork. A groundwork and foundation that must be laid first and then consciously called to mind to create a strong foundation for the design. This common thread must be kept taut throughout the design process. The scene of this thesis is set at the corner of P St. and 23rd St. NW in Washington, DC at the berm of Rock Creek Park; at the brink of City and Nature. / Master of Architecture

The estranged relationship with landscape exhibited by contemporary cultures has been well documented by prominent theorists. Design professionals can begin to reconcile culture and landscape by proposing interventions in everyday landscapes which embrace uncertainty, acknowledge the temporal nature of phenomena, and introduce elements of ambiguity while simultaneously creating pleasing, functional environments. Such interventions encourage meaningful, imaginative experience, encourage multiple readings, and suggest renewed ways of dwelling in landscape. The methodology for this thesis is a two part examination of contemporary approaches to the production of space in significant cultural landscapes. Part one, a position paper, reviews relevant literature and outlines a position to guide design proposals. Part two tests the principals and theories developed in the position paper through proposals for interventions at two sites. The context for the design component is the Crooked Road Musical Heritage Trail. The Crooked Road is an ideal setting in which to explore the potential of interventions that seek to reconcile culture and landscape. It offers participants a framework for the experience of both regional landscape and culture in the form of traditional music rich in landscape themes. Proposals are developed for an abandoned homestead on Shooting Creek and the Floyd Country Store, both in Floyd County, Virginia, along the Crooked Road. The approach to intervention developed in these proposals is intended to guide the development of additional sites along the Crooked Road with the goals of enriching the landscape experience of participants, strengthening regional sense of place, and reconciling estranged relationships with landscape. / Master of Landscape Architecture

A test method and the associated equipment have been developed to investigate the effect of suspended solids on the flow of fluid into a deep injection well system. Preliminary testing indicates that the equipment and test method can be used to determine the permeability of rock samples with a high degree of accuracy. Additionally this equipment can be used in a testing program which will eventually lead to the development of guidelines for the degree of pre-injection treatment required for suspended solids so that the operational life of the well is not impaired.

No description available.

I studied round-tailed ground squirrels (Spermophilus tereticaudus) to determine if presence of water or green vegetation significantly increased reproductive success. I compared the number of juveniles produced, body weights, and diets of squirrels during 1981-84 on 2 plots with green vegetation and no free water, on 3 plots with free water and no green vegetation, and 2 control plots. Reproductive success and body weights of adult and juvenile squirrels were significantly higher (P ≥ 0.001) on plots with green vegetation than on either watered or control plots. Body weights of squirrels on plots with water only and control plots were not significantly different (P ≥ 0.05). Adult squirrels without access to green vegetation during winter and spring failed to reproduce even though free water was readily available. Percent of diet overlap, diversity, and evenness of squirrel diets on control and watered plots were not significantly different. Green vegetation appeared to be the limiting factor for round-tailed ground squirrels.

For spacecraft development, realizing strong supporting ground segment software is as important as designing the actual hardware component of the spacecraft. This thesis describes the author’s contributions to the ground segment software design and development for nanosatellite space missions at the UTIAS Space Flight Laboratory. Particular emphasis is given to the ground segment software for the CanX-3 and CanX-4/-5 missions. For the CanX-3 mission, several software applications are explored, specifically ground control software for the payload on-board computer and star tracker, and mission planning software. For the CanX-4/-5 mission, its mission monitor and control software, and whole orbit data parser are discussed. For each software application, design considerations and decisions made during the development are explained. Furthermore, detailed discussions on their architectural and graphical user interface design and implementation are presented.

For spacecraft development, realizing strong supporting ground segment software is as important as designing the actual hardware component of the spacecraft. This thesis describes the author’s contributions to the ground segment software design and development for nanosatellite space missions at the UTIAS Space Flight Laboratory. Particular emphasis is given to the ground segment software for the CanX-3 and CanX-4/-5 missions. For the CanX-3 mission, several software applications are explored, specifically ground control software for the payload on-board computer and star tracker, and mission planning software. For the CanX-4/-5 mission, its mission monitor and control software, and whole orbit data parser are discussed. For each software application, design considerations and decisions made during the development are explained. Furthermore, detailed discussions on their architectural and graphical user interface design and implementation are presented.