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New Paddocks and Hay Barn, number 1
No full textNew Paddocks and Hay Barn-21 Nov 03. Physical description: color prints (photographs)20X25m
Petroleum hydrocarbons and oyster resources of Galveston Bay, Texas
No full text-Field and laboratory studies of petroleum hydrocarbons in the tissues of the American oyster, Crassostrea virginica, a primary shellfish resource in the Galveston Bay system, were conducted from 1971-1974. Initial ultraviolet spectrophotometric and gas chromatographic analyses of tissues revealed significant amounts of oil-derived petroleum hydrocarbons from oysters collected at Morgan's Point Reef at the lower end of the Houston Ship Channel. Lower values, when detectable, were found in oyster meats collected at natural and artificial reefs scattered throughout the lower bay system. Rapid depuration of petroleum hydrocarbons accumulated in field and experimental exposures was found. In oil-free seawater, oysters released saturated chains and most aromatic fractions rapidly with depuration to below a detectable level (0.1 ppm) taking place within 52 days. Transfer of oysters for depuration purposes shows promise of improving the overall quality of this shellfish resourcehttp://gbic.tamug.edu/request.ht
Summary statistics and graphical comparisons of specific conductance, temperature, and dissolved oxygen data, Buffalo Bayou, Houston, Texas, April 1986-March 1991
No full text-Buffalo Bayou is the major stream that drains the Houston, Texas, metropolitan area. The U.S. Geological Survey has provided specific conductance, temperature, and dissolved oxygen data to the City of Houston for three sites along a 7.7-mile reach of Buffalo Bayou since 1986. Summary statistics and graphical comparisons of the data show substantial variability in the properties during 1986-91. Specific conductance ranged from about 100 microsiemens per centimeter at 25 degrees Celsius at each of the three sites to 17,100 microsiemens per centimeter at 25 degrees Celsius at the most downstream site, at the headwaters of the Houston Ship Channel. Water temperatures ranged from 5 to 33 degrees Celsius. Temperatures were very similar at the two upstream sites and slightly warmer at the most downstream site. Dissolved oxygen ranged from zero at the most downstream site to 11.7 milligrams per liter at the most upstream sitehttp://gbic.tamug.edu/request.ht
An Augmented Machine Learning Approach for Real-Time Terramechanics Modeling
No full textThe purpose of this research was to develop a novel method based on Gaussian process models that can be combined with information from detailed models and field data, such that the model is capable of carrying out real-time simulation of the tire-terrain interaction. The aim of this approach is to be able to provide feedback on tire sinkage, slip, traction, and side forces to a virtual simulator for autonomous off-road vehicles. Such simulators are essential for training autonomous vehicles without the need for extensive field tests. The use of a simulator reduces the cost of autonomous vehicle training and allows for easy modification to the training/testing environment. The present approach is based using precomputed look-up tables, typically based on a Bekker terramechanics model, or a simple Coulomb friction model to determine tractive capabilities. While these provide quick information to be used in vehicle dynamics calculations, they lack the quality and quantity of information required for dynamic off-road conditions under widely different terrain conditions. Furthermore, the model is capable of accommodating disparate data sources with different ranges of validity and also take into account the uncertainties in the predictions.
In this thesis, the efficacy of the hybrid approach is demonstrated by combining a modified Bekker terramechanics model with finite element analysis (FEA) simulations using a Gaussian process regression (GPR) model that is capable of predicting tire forces and sinkage in off-road conditions. The Bekker-style model is valuable due to its simplicity, but it lacks dynamic loading information. While the FEA model provides valuable information about the full tire-terrain interaction it is computationally very expensive and unsuitable for real-time simulations. Therefore, a GPR model is trained to predict the difference between the steady-state information provided by the Bekker-style model and the full response provided by the FEA. Then the Bekker-style model and trained GPR model can be deployed in tandem to predict full response (forces) in a real-time applications such as off-road autonomous driving
A Comparative Analysis of Archaeological and Textual Evidence for Danubian Watercraft, First to Fourth Centuries CE
No full textThe Danube is one of the longest rivers in the world and has been a life source for peoples settled around it for millennia. Alongside local groups, Greeks and Romans used the river as a throughway. Though there are many accounts of the Danube in Roman history, few of them provide insight into what types of vessels were using along the river, despite many documented interactions with local groups. The archaeological record along the Lower Danube, that is the section from the Iron Gates to the Danube Delta, has begun to reveal more evidence of both Roman and local boats used along the ancient course of the Danube, but many of these are found in rescue excavations with limited recording available. In this thesis I combine these two fragmentary sources to examine if the literary accounts are reflective of the archaeological evidence regarding local boatbuilding traditions. Though brief, there are terms in literature which indicate construction methods (����������������), and hull shape (cavatis arborum alveis vs. truncis), which are reflected several times in the archaeological record. Other literary descriptions reveal little about the vessels themselves, but the contexts in which they are found are reflective of Roman perceptions of the users of the vessels. These sources both undermine the capability of the locals to boost military morale and also demonstrate their efficacy, as the Romans were intimidated by those who used the Danube for raiding and stealth attacks. Flat-bottomed barges fastened with closely spaced iron clamps also appear in the archaeological record several times along the Lower Danube and in the greater Danube Basin. Further archaeological research is needed to bolster this theory of a regional vessel type, and such work may continue to yield multiple ship types in the same contexts, increasing the number and variety of vessels from antiquity and perhaps revealing a regional tradition through time. Though there is still much to be excavated, this research has revealed the disparity between Roman descriptions of vessels in use along the Lower Danube and the reality of such boats by examining the archaeological evidence and contextualizing the Roman literature
The Role of Chondrocyte Transdifferentiation in Midpalatal Sutural Growth in Response to Altered Dietary Load
No full textThe biological mechanism for growth of the midpalatal suture is not fully understood. Chondrocyte transdifferentiation into bone cells has been shown to occur in the condylar cartilage but no study has shown this process to occur in the midpalatal suture.
Twelve Acan-CreErt2; R26RTomato;2.3 Col1a1-GFP (Acan mice) and twelve Col10a1-Cre; R26RTomato; 2.3Col1a1-GFP (Col10a1 mice) were randomly allocated into two groups, respectively; a soft and hard food diet (n=6), fed for 6 weeks and then sacrificed for data collection. One-time tamoxifen injections were given to the Acan mice at 3 weeks. MicroCT, palatal widths, chondrocyte cell proliferation, chondrogenic activity and chondrocyte transdifferentiation were all analyzed and compared between dietary loading groups.
There were no significant differences in palatal widths but a significant decrease in bone quality in the soft diet group. Histologically, there were no significant changes in chondrocyte proliferation, and aggrecan expression. However, soft food diet mice had significantly (p<0.05) lower collagen 10a1 expression, and number of chondrocyte derived bone cells, from the early to late stages of maturation, in the midpalatal suture compared to the control.
Altered dietary loading affects midpalatal sutural bone quality, chondrogenesis and chondrocyte transdifferentiation, which may explain differences in postnatal maxillary transverse development
Consumer Food Waste While Dining Out: An Examination of Theory of Planned Behavior, Habits, Empathy, and Mindfulness
No full textThis dissertation explores behavioral intentions behind consumer food waste in the dining-out context, leveraging the Theory of Planned Behavior (TPB). It incorporates habits and empathy as preliminary factors influencing consumers��� intentions. Additionally, it examines the moderating role of mindfulness on food waste tolerance, thereby extending the traditional model. The sample consisted of 633 participants who have dined outside of their home at least once in the past 6 months. By employing Structural Equation Modeling (SEM) and path regression analysis, the study examines four distinct models, highlighting the interplay between subjective norms, attitudes, perceived behavioral control, and external factors such as empathy and mindfulness on food waste intentions.
Significant findings emerged from the models, indicating that empathy significantly impacts food waste intentions through attitudes, perceived behavioral control, and habits, while mindfulness moderates the empathy-intentions relationship, particularly influencing how empathy affects subjective norms and attitudes. These findings aim to offer deeper insights into the psychological underpinnings of food waste, providing a nuanced understanding of how individual differences and cognitive processes contribute to diners' propensity for food waste.
Implications of this research stretch beyond theoretical contributions, offering actionable insights for the hospitality industry and other sectors to enhance operational efficiencies, promote environmental sustainability, and foster corporate social responsibility. The study underscores the importance of targeted interventions and the potential of mindfulness and empathy in shaping consumer behavior towards food waste.
The research contributes to the literature by extending the TPB framework, introducing novel moderators, and underlining the significance of psychological factors in understanding and mitigating consumer food waste. Future research directions are proposed to further explore these dynamics and their practical applications across different contexts and cultures
Contact Mechanics and Tribology of Thermal and Electrostatic Friction Modulation for Surface Haptics
No full textHaptics, an integral part of human-machine interaction, offers a crucial sense of touch for immersive user experiences in many applications, such as virtual and augmented reality. While audio-visual interfaces have been significantly developed, seamlessly integrating touch sensation into these interfaces encounters hurdles due to mechanical and neurophysical complexities of the interaction of human skin with the physical world.
Surface haptics presents a promise for integrating touch into the audio and video interfaces, particularly with the widespread use of touchscreens. Various forms of haptic feedback have been explored in the surface haptics field. Among them, friction modulation-based haptic feedback has been demonstrated as an effective way to offer users a sense of virtual shapes and textures on surfaces. This method, however, has challenges such as variability in frictional performance. This variability hampers consistent user feedback and impedes device commercialization. To address the variability issue, this research aims to elucidate the impact of humidity on friction under electroadhesion based on the electrowetting effect and provides insight into the device design for more consistent haptic feedback. Understanding the intricate surface topography of the human fingerpad, which significantly influences contact mechanics, is another critical aspect. We examine the surface topography of the fingerpad in detail across scales and investigate its impact on contact mechanics studies. Moreover, the surface temperature is another factor that causes the variability of the frictional performances in the surface haptic devices. This work aims to understand the underlying mechanism of the surface temperature effect on friction to provide insight into device design for more consistent haptic feedback and propose a new method to modulate localized friction at lower operating voltages.
Additionally, the development of the 'Touchbot,' a wearable intermediary device, aims to overcome limitations in current surface haptics by providing localized tactile feedback in both lateral and normal directions across the contact patch, thus enhancing the realism of 3D rendering of virtual features. This study will focus on the building block of the Touchbot, an electroadhesive (EA) puck with high EA shear stress and high durability. We look into a more in-depth electromechanical point of view of EA devices, which offers a foundation for EA devices beyond this project
The Role of the Science Teacher: Examination of Science Education Research and Science Teacher Education
No full textScience education has repeatedly identified the teacher as the greatest classroom level factor on student learning. Given the known variance in instructor ability and quality, a failure to consider how an instructor effect may be impacting study results draws into question the validity of study analyses and conclusions that fail to adequately conduct meaningful comparisons. The first investigation of this dissertation examined 79 studies from three leading science education journals to determine the frequency and quality of attention towards instructor differences in sampling efforts. Our findings indicate that instructor difference is rarely considered to a sufficient level within science education research, even in studies with exceedingly small sample sizes. These results are concerning for research practitioners who may be neglecting a key factor in research outcomes.
Though literature surrounding science teacher preparation programs is limited, current evidence suggests that methods courses frequently foreground instructional strategies and activities rather than a more comprehensive framework for science teaching. Potential consequences for this emphasis for preservice educators include a rejection of research-based instructional strategies, weakened instructional effectiveness, and an inability to conduct effective classroom decision-making. Study two in this dissertation analyzed 30 science methods syllabi from varying institutions and education programs to provide preliminary insight into science methods emphases. Our findings support prior claims that science methods courses are highlighting instructional strategies while neglecting the crucial role of the science teacher and teacher behaviors.
The science teacher must clearly understand their role in scaffolding student thinking away from misconceptions and towards accurate understanding of scientific ideas. The final study of this dissertation sought to triangulate findings from study two by interviewing methods instructors to understand their conceptualizations of effective science teaching, the instructional role of the science teacher, and the function of teacher behaviors within that role. Our findings suggest that methods instructors often employ vague metaphorical language when describing the instructional role of the science teacher and rarely address teacher behaviors. Syllabi were found to effectively reflect methods instructors��� conceptualizations of effective science teaching and the function of teacher behaviors but were less effective in representing methods instructors��� conceptualizations of the role of the science teacher
An Augmented Machine Learning Approach for Real-Time Terramechanics Modeling
No full textThe purpose of this research was to develop a novel method based on Gaussian process models that can be combined with information from detailed models and field data, such that the model is capable of carrying out real-time simulation of the tire-terrain interaction. The aim of this approach is to be able to provide feedback on tire sinkage, slip, traction, and side forces to a virtual simulator for autonomous off-road vehicles. Such simulators are essential for training autonomous vehicles without the need for extensive field tests. The use of a simulator reduces the cost of autonomous vehicle training and allows for easy modification to the training/testing environment. The present approach is based using precomputed look-up tables, typically based on a Bekker terramechanics model, or a simple Coulomb friction model to determine tractive capabilities. While these provide quick information to be used in vehicle dynamics calculations, they lack the quality and quantity of information required for dynamic off-road conditions under widely different terrain conditions. Furthermore, the model is capable of accommodating disparate data sources with different ranges of validity and also take into account the uncertainties in the predictions.
In this thesis, the efficacy of the hybrid approach is demonstrated by combining a modified Bekker terramechanics model with finite element analysis (FEA) simulations using a Gaussian process regression (GPR) model that is capable of predicting tire forces and sinkage in off-road conditions. The Bekker-style model is valuable due to its simplicity, but it lacks dynamic loading information. While the FEA model provides valuable information about the full tire-terrain interaction it is computationally very expensive and unsuitable for real-time simulations. Therefore, a GPR model is trained to predict the difference between the steady-state information provided by the Bekker-style model and the full response provided by the FEA. Then the Bekker-style model and trained GPR model can be deployed in tandem to predict full response (forces) in a real-time applications such as off-road autonomous driving