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Some contributions to the theory and applications of nonparametric subset selection procedures
No full textChoosing the best population (based on some parameter performance) among alternative populations can be challenging. The decision-making process depends on what factors are considered important by the person making the decision. On order to determine which populations are better among k of them, an experiment should be designed, and samples from each population are to be taken and the sample size needs to be determined. The target here is not to estimate any unknown parameter, but rather to select the population with the best parameter value. The methodological topic of this dissertation is the nonparametric approach to subset selection of populations so as to contain the “best” population -to be defined with a user-prescribed probability of a correct selection, where we will examine how to apply a versatile, nonparametric framework to efficiently and accurately choose subsets of populations while ensuring that users can control the reliability of the selections made. The common approach in this problem context has been to rank the data (as it is a well established approach) and base the statistical inference on population rank sums. The process of ranking and calculating rank sums is relatively straightforward, facilitating easier interpretation of results and it can be adapted to different contexts and objectives, whether for hypothesis testing or selecting the best population, enabling researchers to base their choices on relative performance as opposed to absolute measurements. In this dissertation, alternative rank scoring methods are considered and shown, in some cases, to yield smaller selected subsets with the same assurance probability as with rank sums. The investigations herein considered are for a two-way experimental block design. An application of the research developed here is made to state motor vehicle traffic fatality rates for the years 1994–2022 with the goal of selecting a subset of states to contain the best (worst) with a prescribed probability. The effects of alternate scoring rules are displayed and shown to support a practical conclusion for other applications
Effective Instructional Practices: Secondary School Teachers View about Teaching Secondary Mathematics with Technology
No full textThe study explores the integration of technology in teaching mathematics, providing current secondary mathematics teachers with effective practices and guiding future mathematics teachers toward a technology-pedagogical approach. In this study, I focused on effective teaching practices with technology in teaching mathematics to current secondary mathematics teachers to guide future mathematics teachers in adopting a technology-pedagogical approach. This research addressed secondary mathematics’ preparedness level to implement effective teaching methods in the digital age. A district from a Midwest state was used to collect data using a sequential explanatory method; a survey was sent to the secondary mathematics teacher with an option for those who wanted to participate in the interview. The results indicated that current teachers have some knowledge of technological tools but not to the full extent that they can integrate them into their daily instruction. The study suggested that current secondary mathematics teachers require ongoing professional development to enhance their technological knowledge and use it effectively
Design and Control of a High-Efficiency System for Electric Air Taxis Using MPC And LQR Control, and GAN-Based Power Electronics with Optimized Lithium-Sulfur Battery Management
No full textLithium-sulfur (Li-S) batteries are a new type of battery that could revolutionize the way we store energy. They have the potential to deliver much more energy than current lithium-ion batteries, which are used in everything from electric cars to smartphones. Li-S batteries work by storing lithium ions in sulfur. Sulfur is a very cheap and readily accessible material, so Li-S batteries have the potential to be much cheaper than lithium-ion batteries. However, some challenges must be addressed before Li-S batteries can be commercialized. One challenge is the shuttle effect. The shuttle effect is a process in which polysulfides (the sulfur compounds that store lithium ions in Li-S batteries) dissolve in the electrolyte and travel to the anode. Another challenge is the formation of lithium dendrites. Lithium dendrites are needle-like structures that can grow on the surface of the battery's anode. A key application for Li-S batteries would be in electric air taxis. Electric air taxis are an exciting new technology that has the potential to revolutionize urban transportation. These aircraft are designed to provide fast, efficient, and environmentally friendly transportation for short-to-medium distance trips within urban areas. They are typically smaller and more agile than traditional helicopters or airplanes and can take off and land vertically, which eliminates the need for a runway. Battery models do not consider specific Li-S battery chemical phenomena - which does not provide an accurate representation of how the battery ages. Furthermore, implementing model predictive control provides an innovative approach to address the dynamic and nonlinear challenges inherent in air taxi flight, offering a sophisticated solution for precise and adaptive thrust control. This dissertation highlights the modeling of an air taxi, as well as a more accurate representation of the battery as it ages. Introducing the MPC ties together the overall control of the vehicl
Congressman Mike Rogers's Bipartisan Legislation in the 111th Congress
No full textList of bipartisan legislation either introduced, co-written, or co-sponsored by Rep. Mike Roger
Studying whether C-C Motif Chemokine Ligand 11 (CCL11) Induces Reactive Oxygen Species in Microglial Brain Macrophages
No full textNeurodegenerative disease is a process in which cells within the nervous system are damaged or die due to conditions in the brain that influence their well-being. Elevated levels of CCL11, an age-related chemokine, have been linked to neurodegenerative disease. Along with CCL11, there is also the increased observance of excess reactive oxygen species (ROS); which are free radicals that damage cellular DNA, RNA, and proteins, leading to the death of cells. This study investigates the impact that CCL11 has in the production of ROS in brain macrophages, known as microglia. Along this line, we hypothesize that CCL11 would activate microglia and increase extracellular ROS in the brain. Leading to the damage of the neuronal tissues and the development of neurodegenerative diseases, such as dementia. To study this hypothesis, we used in vitro cell culture techniques with the microglial cell line, SIM-A9. Results indicate a significant increase in the production of both intracellular and extracellular H2O2, the primary ROS investigated. Furthermore, a potential underlying mechanism that may regulate the production of ROS by CCL11 in microglia was proposed. Understanding the mechanisms that underlie CCL11-mediated ROS production in microglial cells, may provide valuable insight into the pathogenesis of many neurodegenerative disorders. Leading to the development and use of potential therapeutic strategies