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The Top-Down Causality of Thermal Turbines
No full textThe flow of energy down a macroscopic energy gradient turns a passive turbine (e.g., water or wind) to perform mechanical work. Motor enzymes are thermal turbines. The chemical flux down a macroscopic chemical gradient, deltaQ, turns a passive motor reaction cycle to perform mechanical work, deltaPE. We have directly observed that the thermal turbine of muscle is the probability density, not the sum, of its motor enzyme components. Specifically, a thermal turbine is simply entropy, S. We have shown that muscle cyclically changes its form, TdeltaS, when it absorbs deltaQ and then performs work, deltaPE. This is precisely the mechanism described by the second law of thermodynamics. Here, I develop this model and its implications
Geometric Properties of Grassmannians and Color Image Set Recognition Using Quaternionic Grassmannians
No full textRiemannian manifolds provide a basic framework for understanding curved spaces and are widely used in geometry, physics, machine learning, and computer vision. Among them, Grassmannians, which are spaces of linear subspaces, have nonnegative curvature and are useful in data analysis and signal processing. However, their geometric properties are not as well studied as those of the manifold of positive definite matrices, which has clear hyperbolic geometric properties. This dissertation explores both theoretical and practical aspects of Grassmannians and their quaternionic extensions. First, we establish key geometric inequalities on Grassmannians, including a semi-parallelogram law, a law of cosines, and geodesic triangle inequalities. These results give a better understanding of the geometric structure of Grassmannians as Riemannian manifolds and provide useful mathematical tools. Building on this, we propose a new way to recognize color image sets using quaternionic Grassmannians. Traditional methods usually treat color channels separately, which ignores the relationships between them. By using quaternions, which naturally store color information in a compact and meaningful way, we define a new distance measure for quaternionic Grassmannians and prove a triangle inequality for this metric. This allows for a more effective way to recognize color image sets while preserving their structure. To test our method, we run experiments on a benchmark dataset and show that the quaternionic Grassmannian-based approach performs better than traditional methods in color image set classification. These results demonstrate the potential of using Grassmannian geometry and quaternion algebra in computer vision
Mirrors and Windows: Exploring the Intersection of Reflective Practice and Culturally Responsive Pedagogy
No full textThis qualitative case study examined preservice teachers’ experiences in secondary education preparation programs, particularly emphasizing reflective practices in their Culturally Responsive Pedagogy (CRP) and teaching practices. A cultural proficiency self-assessment and reflection, semi-structured interviews, and self-created lesson plans or instructional strategies were explored with six pre-service teachers. Three themes were identified as the findings of this work: Teaching Preparation: Foundation with Gaps, Classroom Experiences: Where Practice Puts You to the Test, Reflective Practices: The Engine for Professional Growth. Recommendations include conducting longitudinal studies to examine preservice teachers’ sustained cultural proficiency, comparative case studies across multiple teacher preparation programs, the mentorship experience, and amplified document analyses to understand how CRP is applied in practice. Finally, seeking a mixed-methods approach to more fully capture the impact of reflective practice on teacher development is recommended in order to illuminate more unique areas in this work
Thematic Analysis and Considerations on J.S. Bach’s Fugues from Das Wohltemperierte Klavier I & II: A Synthesis of Rhetoric from the 17th through the 21st Centuries
No full textABSTRACT This dissertation aims to study and analyze the fugal themes (subjects) of Johann Sebastian Bach’s (1685-1750) Das Wohltemperierte Klavier I (1722) and II (1744). Many scholars have examined and studied the set through numerous ways (Engels, 2006; Groocock, 2003; Ledbetter 2002; Bruhn, 1993; Brook, 1907), however, no single work exists as a guide that has analyzed its themes in such an intricate manner using rhetoric and hermeneutics from different music theorists throughout the centuries. Both volumes are historical landmarks organized in a system that allowed one to play in twelve major and minor keys. Manuscripts show different stages of composition; some were composed much earlier than the whole set, and some were even later transposed to fit the key scheme. Its pedagogical use was perhaps the driving force for its coming together as a set, but ultimately bound as a culmination of an art that has defined baroque polyphony.For this paper, thematic analysis of Bach’s fugues are done through the analysis and identification of the heads and tails, as proposed by Harrison (2008); the identification of the figurae as proposed by authors: Printz (1673), Praetorius (1619), Beyer (1703), Walther (1703), and Kürzinger (1763); the analysis and identification of rhythmic feet as explained by Williams (1892), while paying careful attention to Bach’s mensural notation according to Kilgore (1973) as evidence of Bach’s congruence to the Greek ideals of rhythm. Particularly, analysis of the subjects used in the fugues of the first and second volume include: identification of the motive; identification of the tails and heads of the subject; identification of subject figurae such as, groppo, suspirans, messanza, corta, accentus, tirata and circolo. Furthermore, analysis of rhythmic feet, namely, the trochee, dactyl, paeon, and the ionicus, as well as the identification of the placement of the anacrusis�"which according to Aristoxenus (360 B.C.), gives it (subject) strength�"All these as evidence that Bach was using rhythmic rhetoric in a way paralleling the Greek ideals. The observations within these analyses show the apparent uniqueness of each subject, their absence of unity as a volume, their dispositions suggesting no intended relation to the sequence of the performance, and the apparent more complex subjects used later in the volume. More observations should arise upon the completion of the analyses, including the congruity or incongruity of the rhetoric as proposed by the theorists, and evidence that most Bach’s themes fit the rhetorical schemes. This dissertation sheds new light to a better understanding of Bach’s musical ideas and prove to be an invaluable resource to music theorists, scholars, and performers as a reference to fresh performance practice, or theoretical works that may touch on its themes that is the heart of any fugal work
Comparison of Fitness Training Efficacy of In-Person to Online Coaching on Goal Attainment for Adults
Get PDFCertified personal trainers and online coaches create training programs that are designed to guide their clients to achieving their fitness goals. Frequently a client will not fully define what their goal(s) is, rather they use subjective terms such as “I want to lose weight” or “I would like to become more toned.” From these simple statements a qualified personal trainer or fitness coach can use motivational interviewing, which Sutton (2022) defines as a client-centered method to guide them into enhancing intrinsic motivation to change, to resolve the ambivalence of the goal statements into a clear and concise goal. Once the goal is defined, a training program can be developed. During the initial consultation, the fitness professional will collect anthropometric measurements such as scale weight, body mass index, percent body fat, height, and both waist and hip circumference data on the client. This information is used to establish a realistic timeframe for achieving the client’s goal(s) based on faithful execution of the personalized training program. This process is completed for clients who train in-person as well as for those that train via an online coaching web application. The personalized training program will contain elements of resistance, cardiovascular endurance, and flexibility and balance training. Current studies detailing the value and efficacy of a specific training technique are numerous (Afari et al., 2022; Arana et al., 2012; Bellicha et al., 2021; Corres et al., 2018; Hassannejad et al, 2017; Kim et al., 2021; McCormack et al., 2018; McIlroy et al., 2020; Meinerz et al., 2023; Stanula et al., 2015; Yu et al., 2022). Locating studies that focus on comparison of training delivery methods, such as in-person to online, are sparse. This study was created to reflect the personal experience of the primary researcher who is a certified personal training and online coach working with clients on a daily basis. The aim is to determine the efficacy of both her in-person training skills and online coaching skills and which may, in comparison, be superior. To facilitate this study, I, as primary researcher, and personal trainer/online coach, reviewed my past and current client files and identified those client records that had the necessary anthropometric data from pre- and post-training programs that would allow for some form of comparison to be made. The research method chosen for this study is quasi-experimental repeated measure design of initial recorded anthropometric measurement data for all study participants prior to executing a specific fitness training program, whether the method of delivery was in-person or online coaching. The initial anthropometric measurement data is then compared to the end of program data collected for the same variables identified for analysis. Key words: fitness training, in-person training, online coaching, body composition, body mass index, body fat analysis, bioimpedance analysis, waist-to-hip rati
Urbanization's Effects on Avian Morphology, Hormones, and Behavior Across Ontogeny
No full textAs the human population continues to grow at an unprecedented rate, anthropogenic changes are rapidly altering the remaining natural areas of the world. Urban-related stressors, such as lower food availability, the urban heat island, artificial light at night, and other pollution directly impact urban wildlife biodiversity and fitness. How wildlife cope and adapt to these urban modification's vary, depending on species, natural history, and location. However, most studies report differences in the urban phenotype, mostly in behavior, phenology, physiology, and morphology. While knowledge of phenotypic shifts in urban wildlife is growing, understanding the particular ecological pressures driving these changes and the mechanisms leading to phenotypic change and ultimately survival, is still lacking. Therefore, it is critical to understand how urbanization and its unique environmental factors affect the wildlife that reside in our cities. This dissertation is a multifaceted investigation of the impacts and mechanisms of urban ecology and evolution, in which I: 1) investigated behavioral, morphological, and physiological phenotypic shifts of an urban bird across ontogenetic stages (Chapters 1, 2, and 3); 2) highlighted the role maternal hormone transfer may play as a mechanism for urban adaptation (Chapters 2 and 3); and 3) directly tested the effects of limiting food, one of the most prominent urban challenges, on shaping morphological and physiological traits through a field manipulation experiment (Chapter 3). We were able to show clear phenotypic shifts in urban birds, including reduced incubation behavior, reduced masses and condition of eggs, nestlings, and adults, and elevated physiological glucocorticoid levels in nestlings and adults. Additionally, we showed that maternal hormone transfer across multiple endocrine pathways differs across an urban gradient with elevated maternal deposition of corticosterone and testosterone and reduced deposition of maternal thyroxine concentrations in urban yolks. Lastly, we provide experimental evidence that limited food, i.e. , reduced insect abundance, in urban environments is likely the urban ecological pressure driving these differences in morphology, maternal hormone transfer, and physiological responses in an insectivorous urban bird. This dissertation advances our understanding of how urbanization and its unique challenges affect urban wildlife and pinpoints a specific aspect of the urban environment where conservation management can implement actionable changes
Optimization of Thermoelectric Generators to Power Monitoring Platforms of SNF Canister Internal Conditions: Numerical Simulations
Get PDFSpent nuclear fuel (SNF) may need to be stored in dry storage systems (DSS) for longer times than the systems were originally licensed for. Therefore, it is important to monitor the internal conditions of these canisters to ensure that their components and contents remain safe. The overall objective of the current research is to develop a wireless self-powered platform for monitoring the internal conditions of a wide variety of canister designs. The sensors and wireless data transmission systems will be powered using Thermoelectric Generators(TEGs) that harvest thermal energy from the decay heat of the SNF assemblies and convert it into electric power. The amount of harvested power by the TEGs depends on their dimensions and location. In this work, three-dimensional computational fluid dynamics (CFD) simulations are conducted to optimize the location of the TEGs within a NUHOMS 61-BT canister placed inside an HSM storage overpack. Two thicknesses of the TEGs are investigated to determine the optimal configuration that will maximize the amount of harvested power. The conversion efficiency of the TEGs is assumed to be temperature-dependent, and two different TEG figures of merit are considered. The electric power output of the TEGs and the frequency between measurements are determined for 50 years of storage. The results show that for a canister total heat generation of 18.3 kW and TEG surface area of 0.32 m 2 , TEGs with a 푍푇 value of 1 generate up to 66.10 mW of electric power, with an efficiency of 0.0760% at 0 years of storage and 8.85 mW (0.0290%) at 50 years of storage for a canister total heat generation of 7.2 kW. Assuming an energy consumption of 10.12 J for the wireless monitoring platform, a surface area of 0.1 m 2 is required to achieve a time between measurements of 8 minutes at 0 years of storage and 60 minutes at 50 years of storage
Asphalt Pavement Industry Survey on Recycled Materials and Warm-Mix Asphalt Usage: 2022
Get PDFThe objective of this survey, first conducted for the 2009 and 2010 construction seasons, is to quantify recycled materials used and WMA produced annually by the asphalt pavement industry to document the deployment of these technologies to understand where they are being used and where they are underutilized. Results show significant growth in the use of RAP, RAS, and WMA technologies since 2009, although the rate of year-over-year growth has generally slowed since 2013.The Federal Highway Administratio
Dissecting the Complex Behavior of Hyperelastic Conductive Materials Through Materials Model
No full textThe hyperelastic conductive system that can remain conductive despite extensive stretching or large deformation holds immense potential, such as being used as wearable, soft-stretchable electronics, stretchable sensors, soft robotic systems, and flexible biomedical devices. Despite these vast prospects, challenges lie in material selection, maintaining conductivity or structural integrity, and accurately predicting the functional behavior during extensive deformation. Because of the absence of comprehensive predictive platforms, researchers depend on multiple trial-and-error approaches, hindering the development of well-engineered soft conductive systems. One promising approach to achieve such a system is injecting a well-understood conductive fluid into a pre-engineered hollow hyperelastic polymer. While it is crucial to understand the conductive fluid to predict its electrical response during usage, designing the polymer is also essential to maintaining the performance and seamlessly integrating the system into our lives. This dissertation has contributed to this gap by dissecting the fundamental characteristics of two key components" liquid metal and hollow thermoplastic polymers" widely used for soft electronics. Gallium alloys, often called liquid metals, are preferred by researchers over other conductive fluids due to their excellent metal-like conductivity and fluidity at room temperature. However, liquid metal gains an oxide layer by interacting with air, which is vital in manipulating the fluidity and predicting its behavior. Notably, it may create perturbed pendant droplets because of the oxide layer, which traditional surface tension measurement techniques struggle to characterize. A machine learning-based technique has; been developed to approximate the surface tension of perturbed droplets. This was further harnessed to observe the modulus decrease of the oxide layer due to repeated oscillation, indicating that the oxide may get softer under repeated strain. Moreover, to gain deeper insights into the change in the oxide layer from chemical interaction, the reaction dynamics of the oxide with chlorosilane have been explored, leading to the fabrication of open-ended microfluidic channels on various surfaces. In parallel with contributing to a better understanding of the liquid metal, efforts have been directed towards investigating hollow thermoplastic polymers that are commonly utilized for embedding liquid metal to fabricate soft electronics. The limited understanding of hyperelastic materials has led researchers to depend on trial-and-error approaches to determine proper materials and geometry for a particular application, obstructing the growth of the soft electronics field. An experimental-computational platform has been established to overcome this problem. A rheological model was calibrated from simple experimental data with more than 99% confidence, enabling further investigation in finite element analysis, COMSOL. Additionally, stitching is commonly used to integrate soft electronics or wearables into our fabric. To assess how this process might impact rheological behavior, the same approach has been used to investigate the rheological alteration of a cotton-stitched fabric composite, showcasing the versatility of our platform in evaluating composite materials. Overall, this dissertation contributes to advancing our understanding of hyperelastic conductive materials and advancing the existing knowledge towards the design and development of soft electronics
Dietary Shifts and Cultural Complexity: Exploring Late Holocene Faunal Remains and Marine Mammal Hunting on the Northern Channel Islands
No full textIn this thesis, I examine the faunal remains from 16 archaeological sites across Santa Rosa, Santa Cruz, and San Miguel Islands to explore how dietary changes during the Late Holocene allowed for the development of increased population density and cultural complexity, particularly in relation to marine mammal hunting, on the Northern Channel Islands. I test two primary hypotheses that were formulated from the perspective of the Diet Breadth Model. To test each hypothesis, I used three lines of evidence: radiocarbon dating, faunal analysis, and shellfish diversity calculations. The first hypothesis is that as population density continued to increase throughout the Late Holocene on the NCI, the Island Chumash diversified their diets to include greater amounts of marine mammal and finfish. The second hypothesis is that changes in the observed marine diet through the archaeological record will support increased social complexity through population distribution and technological advancements. The results of the faunal analysis for this thesis revealed that throughout the Late Holocene, the trajectory of fishing continues to increase through time while marine mammal hunting experiences a less consistent pattern and is most prevalent during the Middle Period (~2,500-800 cal BP). These patterns take form following the introduction of the single-piece shell fishhook (~2,500 cal BP) and the tomol plank canoe (~1,500 cal BP). Moreover, shellfish gathering remained an important dietary component which continued to diversify throughout the Late Holocene, persisting alongside the increased consumption of higher trophic level species such as pelagic fish and marine mammals. These dietary shifts were able to support the rapid population growth that occurred on the NCI around 1,300 cal BP and was followed by shifting settlement patterns, increased production of specialized crafts, and the development of trade networks between the islands and the mainland during the Middle to Late Period Transition (MLT; 800-650 cal BP). Understanding how major demographic and cultural shifts were able to occur on the NCI is essential for grasping human decision-making processes and furthers our knowledge on the importance of technological advancements and dietary changes during the Late Holocene