With higher demands on biomass, the ability to accurately estimate the amount in a stand is more important now than ever before. Existing models currently in use by the Forest Inventory and Analysis (FIA) program of the United States Department of Agriculture (USDA) Forest Service include the Component Ratio Method (CRM). However, testing of the CRM models is needed to validate and calibrate them. The objective of this research was to test and develop a system of equations capable of producing consistent volume and biomass estimates for standing trees of commercially important hardwood species in the southeastern United States. Testing and comparing was done through use of new and legacy data to establish component ratios of trees and contrast these results to those from existing models. Specifically, analyses were completed for models of merchantable and whole stem volume, wood densities models and averages, and the component ratios for wood, bark, branches, and foliage. The existing models were then calibrated and adjusted. Results on accuracy and fitted results of updated models are reported, along with testing the effects of applying updated models over the state of Virginia. / Master of Science

My thesis explores the potential manipulation of Roman brick using a Flemish bond, corner quoining, and barrel vaulting. The design uses this brick module to re-interpret the Ancient Roman domus, an urban residence embedded within the heart of the city. This classical inspiration is apparent in the tripartite plan and elevation as well as the use of the Golden Ratio, a classical proportioning system, incorporated throughout the design, revealed on both large and small scales. However, the emphasis of the project is on true brick construction, a process irrelevant to historical allusion. / Master of Architecture

The work is focused in investigating the effectiveness of discretized damping tapes applied to a cantilever beam subjected to free and forced vibrations. The work is divided into three main sections. First, we performed material characterization of the viscoelastic (VE) pressure sensitive adhesive layer of the damping tapes. To do so, we designed a novel quad shear specimen to measure shear storage and loss moduli, and tan delta from dynamic mechanical analyzer measurements. Second, the optimal discretization length for different damping tapes was experimentally determined and analytically verified using linear viscoelasticity and basic strength of materials and vibrations principles. These results showed a mean to improve the damping of a structure without increasing the weight of the added damping layer. Third, a nonlinear analysis was performed for cantilever beams with damping layers subjected to parametric excitation. Comparison of the response amplitude of the parametrically excited beam was performed for different discretization lengths, and system identification of the nonlinear parameters was carried out. The effects of large deflections of a beam under parametric excitation were analyzed; large deflections were found to induce localized buckling of the stiff constraining layer of the damping tape that would invalidate some of the assumptions and analytical solutions that do not take such phenomena into account. / Master of Science

Reproductive efficiency in beef cattle can be improved with reproductive technologies at the herd, individual cow, and embryonic levels. Decreasing the bull:cow ratio for natural service after fixed time artificial insemination (FTAI) can alleviate economic burden associated with FTAI. In experiment 1, the total number of cows exposed per bull was negatively correlated with pregnancy rate to natural service on first return to estrus after FTAI in fall herds. The number of open cows per bull in fall herds using one natural service sire was negatively correlated with pregnancy rate on first return to estrus. There was no correlation between number of cows exposed per bull and pregnancy rates in fall herds with multiple sires or in spring herds. However, bull:cow ratio accounted for only 5–11% of the variation in pregnancy rates, thus we conclude that a reduced bull:cow ratio did not affect natural service return to estrus pregnancy rate. Experiment 2 examined how supplementing calcium salts of soybean oil (CSSO) improves beef cow fertility. Non-pregnant cows received supplement with either saturated fat or omega-6 rich CSSO. There were no changes in dominant follicle diameter, corpus luteum volume, plasma progesterone, or endometrial gene expression (PTGES and AK1B1, PPARA, PPARA, PPARD) between treatments. Plasma and follicular fluid fatty acid compositions were altered between treatments. Experiment 3 examined if size parameters of zygotes have potential as a non-invasive, objective embryo selection method. The outer diameter, area of ooplasm, and thickness of zona pellucida (ZP) was digitally measured on individual artificially activated oocytes and in-vitro fertilized (IVF) zygotes. Larger outer diameter increased probability of development to the blastocyst stage by days 7 and 8 for activated oocytes and tended to by day 8 for IVF zygotes. Thinner ZP increased probability of development to blastocyst stage on days 7 and 8 for oocytes, and to day 8 for IVF zygotes. Area did not affect development but was positively correlated with blastomere number on day 8. An interaction between diameter and ZP thickness was observed in zygotes, but not activated oocytes, suggesting oocyte activation is not always a suitable replacement for in-vitro fertilization. / Doctor of Philosophy / We need to improve reproductive efficiency in beef cows if we are to combat the challenges of producing more food while using less resources due to limited land availability and concerns with greenhouse gas emissions from agriculture. In cow-calf production systems, this means producing one healthy calf per cow per year. Cattlemen can implement a variety of assisted reproductive technologies to achieve this goal. Achieving maximal reproductive efficiency will require using technologies that are incorporated into herd management, individual animal care, and in vitro embryo production. Fixed time artificial insemination (FTAI) allows cattlemen to maximize the number of cows becoming pregnant and calving earlier in the season to increase efficiency. Unfortunately, use of FTAI is uncommon in cow-calf production systems because of labor and economic restraints. In order to improve economic feasibility of FTAI, bull-related costs need to be reduced, which can be done through increasing the number of cows serviced per bull (decreasing the bull:cow ratio). This study retrospectively examined correlations between the bull:cow ratio and pregnancy rate on first return to estrus after FTAI. There was little to no correlations between bull:cow ratio and pregnancy rates, and if they were significant, there was much variation in the data. With this we concluded that a reduced bull:cow ratio does not affect pregnancy rate on first return to estrus, allowing producers to increase the number of cows serviced by a single bull and reduce bull related costs. Supplementing calcium salts of soybean oil (CSSO) that are rich in omega-6 fatty acids can enhance beef cow fertility, but it is unclear why this happens. Using non-pregnant cows as a model, we studied the effects of either saturated fat or CSSO on reproductive parameters such as ovarian structures, hormone concentrations, and uterine gene expression. There were no changes in any of these parameters between treatments, but there were changes in the concentrations of certain plasma and follicular fluid fatty acids. There was also reduced activity of lipid metabolism enzymes. We were unable to pinpoint how CSSO supplementation improves reproduction, but the altered fatty acid content of tissues and altered enzyme activity likely plays a key role, thus ultimately impacting fatty acid utilization and growth of the embryo. In-vitro embryo production can increase the number of offspring produced from a single female and accelerate the incorporation of animals with high genetic merit into herds. To obtain optimal pregnancy rates with in vitro embryos, we should develop non-invasive, objective methods for identifying the most viable embryos. This study examined if size parameters of activated and fertilized oocytes are indicative of successful development. We discovered that oocytes with large diameters and those with thin zona pellucida were most likely to develop to the blastocyst stage, and that the area of the cell was positively correlated with blastocyst total cell number. An interaction between diameter and ZP thickness was observed in zygotes, but not activated oocytes, suggesting oocyte activation is not always a suitable replacement for in-vitro fertilization. This suggests that digital measurements of fertilized oocytes may have potential as objective selection criteria. Addressing issues of reproductive inefficiency in beef cows requires a comprehensive approach, as there is not one ideal solution. Management techniques can alleviate the cost of FTAI by reducing the number of bulls used without affecting pregnancy rates. Supplementing CSSO can alter tissue fatty acids to enhance fertility. Finally, the efficiency of in vitro embryo production can be improved by selecting better embryos for transfer without compromising the embryo. Combinations of all these techniques can create more reproductively efficient animals.

A partial nitritation-anammox continuous flow reactor (CFR) was operated for eight months demonstrating that a mixture of large anammox-supported aerobic granules (ASAGs) and small conventional aerobic granules (CAGs) can be maintained stably for extended periods of time. The influent NH4+ was kept at 50 - 60 mg N L-1 to verify that the upper range of total ammonia nitrogen (TAN) for domestic wastewater can supply an inhibitory level of free ammonia (FA) for nitrite oxidizing bacteria (NOB) suppression in CFRs at pH around 7.8. The ammonia oxidizing bacteria (AOB):NOB activity ratio was determined for a series of granule sizes to understand the impact of mass diffusion limitation on the FA inhibition of NOB. When dissolved oxygen (DO) limitation is the only mechanism for NOB suppression, the AOB:NOB ratio was usually found in previous studies to increase with the granule size. However, the trend is reversed when FA has an inhibitory effect on NOB, as was observed in this study. The decrease in AOB:NOB ratio indicates that the resistance to the diffusion of FA along the granule radius limited its ability to inhibit NOB. This means smaller granules, e.g. diameter < 150 microns, are preferred for nitrite accumulation when high FA is present, e.g. in the partial nitritation-anammox process. The trend was further verified by observing the increase in the apparent inhibition coefficient, KI,FAapp, as granule size increased. This study for the first time quantified the effect of diffusion limitation on the KI,FAapp of NOB in granules and biofilms. A mathematical model was then utilized to interpret the observed suppression of NOB. The model predicted that NOB suppression was only complete at the granule surface. The NOB that did survive in larger granules was forced to dwell within the granule interior, where the FA concentration was lower than that in the bulk solution. This means FA inhibition can be taken advantage of as an effective means for NOB suppression in small granules and thin biofilms. Further, FA and DO were found to be both required for the stratification of AOB and NOB in partial nitritation-anammox CFRs. The structural stratification commonly observed in granules is then concluded to be a consequence but not a cause of the NOB suppression. / MS / A partial nitritation-anammox continuous flow reactor (CFR) was operated for eight months demonstrating that granular sludge can be maintained stably for extended periods of time. In this approach, NH3 is only partially converted to NO2 - (partial nitritation), and the conversion to NO3 - is prevented by the suppression of nitrite oxidizing bacteria (NOB). NH3 and NO2 - are then utilized by anammox bacteria to create N2 gas. The influent NH4 + fed to the reactor was kept at 50 to 60 mg N L-1 to verify that the upper range of total ammonia nitrogen (TAN) for domestic wastewater can supply a sufficiently high level of free ammonia (FA) to inhibit NOB growth in CFRs at a pH around 7.8. It is expected that the penetration of a substrate into granule sludge will experience diffusional resistance as it moves from water to denser solid material and is consumed by bacteria. The ammonia oxidizing bacteria (AOB):NOB activity ratio was determined for a series of granule sizes to understand the impact of mass diffusion limitation on the FA inhibition of NOB. When dissolved oxygen (DO) limitation is the only mechanism for NOB suppression, the AOB:NOB ratio was usually found in previous studies to increase with the granule size. However, the trend is reversed when FA has an inhibitory effect on NOB, as was observed in this study. The decrease in AOB:NOB ratio indicates that the resistance to the diffusion of FA, which increases with increasing granule size, along the granule radius limited its ability to inhibit NOB. This means smaller granules, e.g. diameter < 150 µm, are preferred for NO2 - accumulation when high FA is present. The trend was further verified by observing the increase in the apparent inhibition coefficient, KI,FAapp, as granule size increased. This coefficient quantifies the effectiveness of an inhibitor, with larger values indicating weaker inhibition. This study for the first time quantified the effect of diffusion limitation on the KI,FAapp of NOB in granules and biofilms. A mathematical model was then utilized to interpret the observed suppression of NOB. The model predicted that NOB suppression was only complete at the granule surface. The NOB that did survive in larger granules was forced to dwell within the granule interior, where the FA concentration was lower than that in the bulk solution. This means FA inhibition can be taken advantage of as an effective means for NOB suppression in small granules and thin biofilms. Further, FA and DO were found to be both required for the stratification of a layer of AOB at the surface over a layer of NOB in partial nitritation-anammox CFRs. The structural stratification commonly observed in granules is then concluded to be a consequence but not a cause of the NOB suppression.

This thesis investigates the effect of aspect ratio on visual perception in scatterplots. Four tasks explored how the aspect ratio affects participants' perception of distance, amount, and correlation in scatterplots. The results showed that square aspect ratio scatterplots are more suitable for detecting length and number, while rectangular aspect ratio scatterplots are better for detecting correlation. In addition, the JND (Just Noticeable Difference) was used in evaluating the visual perception of scatterplots in this experiment. The findings of this study have important implications for the design of scatterplots in data visualization, as well as for future research on visual perception in data visualization. / Master of Science / This thesis focuses on understanding how the aspect ratio of scatterplots affects how people perceive data. Scatterplots are graphs that display data points on two variables, allowing researchers to identify relationships between variables visually. The aspect ratio of a scatterplot refers to the percentage of its width to height. This study found that people are better at detecting distances and amounts in scatterplots with a square aspect ratio. In contrast, they better see scatterplot correlations with a rectangular aspect ratio. The results suggest that the aspect ratio of a scatterplot plays a critical role in how people perceive and interpret data. These findings are essential for researchers, analysts, and designers who want to create compelling and accurate data visualizations.

The Golden Ratio House is primarily an architectural object constructed from a cube, which is the necessary point of origin for this project. Similar to the rules of invention, its purpose lies in its own making. Its rational construction, using the proportion of the golden ratio, produces an autonomous form. The translations and transformations of the cube are dialectic. The resulting form of the House is a product of the logic necessary for its existence. / Master of Architecture

In various business and military settings, there is an expectation of on-demand delivery of supplies and services. Typically, several delivery vehicles (also called servers) carry these supplies. Requests arrive one at a time and when a request arrives, a server is assigned to this request at a cost that is proportional to the distance between the server and the request. Bad assignments will not only lead to larger costs but will also create bottlenecks by increasing delivery time. There is, therefore, a need to design decision-making algorithms that produce cost-effective assignments of servers to requests in real-time. In this thesis, we consider the online bipartite matching problem where each server can serve exactly one request. In the online minimum metric bipartite matching problem, we are provided with a set of server locations in a metric space. Requests arrive one at a time that have to be immediately and irrevocably matched to a free server. The total cost of matching all the requests to servers, also known as the online matching is the sum of the cost of all the edges in the matching. There are many well-studied models for request generation. We study the problem in the adversarial model where an adversary who knows the decisions made by the algorithm generates a request sequence to maximize ratio of the cost of the online matching and the minimum-cost matching (also called the competitive ratio). An algorithm is a-competitive if the cost of online matching is at most 'a' times the minimum cost. A recently discovered robust and deterministic online algorithm (we refer to this as the robust matching or the RM-Algorithm) was shown to have optimal competitive ratios in the adversarial model and a relatively weaker random arrival model. We extend the analysis of the RM-Algorithm in the adversarial model and show that the competitive ratio of the algorithm is sensitive to the input, i.e., for "nice" input metric spaces or "nice" server placements, the performance guarantees of the RM-Algorithm is significantly better. In fact, we show that the performance is almost optimal for any fixed metric space and server locations. / Master of Science / In various business and military settings, there is an expectation of on-demand delivery of supplies and services. Typically, several delivery vehicles (also called servers) carry these supplies. Requests arrive one at a time and when a request arrives, a server is assigned to this request at a cost that is proportional to the distance between the server and the request. Bad assignments will not only lead to larger costs but will also create bottlenecks by increasing delivery time. There is, therefore, a need to design decision-making algorithms that produce cost-effective assignments of servers to requests in real-time. In this thesis, we consider the online bipartite matching problem where each server can serve exactly one request. In the online minimum metric bipartite matching problem, we are provided with a set of server locations in a metric space. Requests arrive one at a time that have to be immediately and irrevocably matched to a free server. The total cost of matching all the requests to servers, also known as the online matching is the sum of the cost of all the edges in the matching. There are many well-studied models for request generation. We study the problem in the adversarial model where an adversary who knows the decisions made by the algorithm generates a request sequence to maximize ratio of the cost of the online matching and the minimum-cost matching (also called the competitive ratio). An algorithm is α-competitive if the cost of online matching is at most α times the minimum cost. A recently discovered robust and deterministic online algorithm (we refer to this as the robust matching or the RM-Algorithm) was shown to have optimal competitive ratios in the adversarial model and a relatively weaker random arrival model. We extend the analysis of the RM-Algorithm in the adversarial model and show that the competitive ratio of the algorithm is sensitive to the input, i.e., for “nice” input metric spaces or “nice” server placements, the performance guarantees of the RM-Algorithm is significantly better. In fact, we show that the performance is almost optimal for any fixed metric space and server locations.

The introduction of airbags has not significantly reduced serious thoracic injury for belted occupants in frontal crashes. This thesis has investigated the effectiveness of airbags and the characteristics of residual thoracic organ injury incurred by belted occupants in vehicles equipped with airbags. This study was based on the injury outcome of over 28,000 belted front seat occupants involved in frontal collisions. Data for this analysis was extracted from National Automotive Sampling System / Crashworthiness Data System (NASS/CDS) case years 1993-2007. The use of odds ratios for comparing the effect of airbags on the occurrence of injury has shown that airbags do not significantly increase protection against head and chest injuries. Overall, the lower extremity and the upper extremity were shown to be adversely affected by airbags. The face was the only body region that was shown to benefit from the combination of seat belts and airbags as compared to seat belts alone. An investigation into the characteristics and distributions associated with thoracic organ injuries showed the heart and great vessels are the only thoracic organs that showed a significant reduction in the rate of injury with the inclusion of airbags. In vehicles with airbags, the thoracic organs are injured more frequently than the ribs. When occupants sustain thoracic organ injury, the delta-V of the crash for vehicles with and without airbags is not significantly different. The odds of serious injury to the lungs and spleen are higher for occupants in vehicles with airbags as compared to those in vehicles without airbags. Rib fracture was found to be a poor predictor of moderate to fatal thoracic organ injury. Only 31-61% of thoracic organ injuries occur with an associated rib fracture. / Master of Science

In somatic cells, checkpoint pathways trigger cell cycle arrest in response to unreplicated or damaged DNA by inhibiting the activity of cyclin-dependent kinases (Cdks). In the Xenopus laevis embryo, checkpoints are not operational until the midblastula transition (MBT). Studies in cell-free egg extracts indicate that a threshold concentration of nuclei, which approximates the MBT concentration, is required to elicit a checkpoint. The checkpoint response to unreplicated DNA in the extract prevents transition into mitosis by inhibiting Cdk1/cyclin B, causing an increase in the minimum amount of cyclin B necessary to enter mitosis, termed the cyclin threshold. Once the threshold of cyclin is maintained or exceeded, the system will proceed into mitosis after a lag time. We have investigated the relationship between nuclear concentration and cell cycle regulation in the extract. By precisely regulating the concentration of cyclin B and nuclear content in extract samples, we have found 1) the concentration of nuclei affects cyclin B thresholds and lag time of entry into mitosis, 2) elevated cyclin thresholds caused by DNA replication blocks are further increased by increasing the concentration of nuclei, and 3) double-stranded DNA breaks in the extract system do not affect cyclin thresholds or lag time of entry into mitosis within the range of nuclear concentrations that can be efficiently replicated. This data provides evidence of the importance of the nucleocytoplasmic ratio in normal cell cycle progression and its importance for checkpoint acquisition during early Xenopus laevis development. / Master of Science