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What the New CAFE Standard Would Mean
No full textInformation sheet about Congressman Rogers's opposition to an amendment to increase the Corporate Average Fuel Economy (CAFE) standar
Google Workspace In The Anatomy Dissection Lab – Approach To Enhance Multifaceted Communication In Large Group Setting
No full textPoint Estimators and Confidence Intervals Under Sequential Sampling Strategies with Applications
No full textStatistical inference is the process of making informed decisions about a larger population by analyzing a smaller group of data collected with some form of sampling. In many statistical inference problems, where some prescribed accuracy is desired, the required sample size often depends on unknown population parameters and thus remains unknown. Then, it is necessary to conduct a sequential sampling procedure, where an experimenter takes one observation at a time successively until a predefined stopping rule is satisfied. This thesis involves sequential sampling procedures dealing with three statistical inference problems. These are (i) bounded variance point estimation (BVPE) of a function of the scale parameter in a gamma distribution with known shape parameter; (ii) fixed-width confidence interval (FWCI) estimation for comparing two independent Bernoulli proportions; and (iii) fixed-accuracy confidence interval (FACI) estimation for the shape parameter of a Weibull distribution based on record data. In the first research problem, given a gamma population with known shape parameter α, we develop a general theory for estimating a function g(·) of the scale parameter β with bounded variance. We begin by defining a sequential sampling procedure with g(·) satisfying some desired condition in proposing the stopping rule, and show the procedure enjoys appealing asymptotic properties. After these general conditions, we substitute g(·) with specific functions including the gamma mean, the gamma variance, the gamma rate parameter, and a gamma survival probability as four possible illustrations. For each illustration, Monte Carlo simulations are carried out to justify the remarkable performance of our proposed sequential sampling procedure. This is further substantiated with a real data study on the weights of newborn babies. In the second research problem, we are interested in the proportions of a common characteristic possessed by two independent dichotomous populations, denoted by P1 and P2. We propose sequential sampling procedures for constructing FWCIs to compare the magnitude of P1 and P2 based on the log transformation and the logit transformation, respectively, which are followed by Monte Carlo simulations. We then implement these sequential sampling procedures to solve a real-world problem of mobile games A/B testing. In the third research problem, we focus on utilizing the record data to estimate the shape parameter of a two-parameter Weibull population, which is widely used in lifetime data analysis. A sequential sampling procedure is developed for constructing a FACI for the Weibull shape parameter β, no matter whether the scale parameter α is known or unknown
Strategic Planning Team Reflects Intensive Participation, Readiness to Innovate, Mar. 2024
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Numerical analysis and simulations of coupled free flow and dual porosity models
No full textCoupled free-flow and porous media flow can be found in many applications in science and engineering, including oil extraction, groundwater contamination, etc. However, these problems are hard to solve exactly and fast, accurate numerical methods are necessary to solve them computationally. The coupled problems we consider in this thesis are the dual-porosity Stokes problem and its nonlinear version dual-porosity Navier-Stokes problem that model flow in regions partially occupied by naturally fractured porous media. These problems combine flow in microfractures and the porous matrix, governed by the dual-porosity equations, with free flow in macrofractures/conduits, governed by the (Navier-)Stokes equations. The dual porosity and (Navier-)Stokes equations are connected through four interface conditions: mass conservation, balance of forces, the Beavers-Joseph-Saffman condition, and a no-exchange condition between the matrix and the conduits. This thesis introduces, analyzes, and tests through numerical experiments hybridizable discontinuous Galerkin methods for solving Stokes-dual-porosity and Navier-Stokes-dual-porosity problems. We prove existence, uniqueness, and stability of weak solutions to both problems under appropriate data restriction in the nonlinear case. Then, we introduce hybridizable discontinuous Galerkin (HDG) methods, prove well-posedness of the numerical schemes, and present a priori error analyses. Our error estimates show optimal convergence in the energy norm for the Stokes velocity and pressures in Stokes, microfacture, and the martix. In addition, our HDG method is strongly mass conservative and has the typical advantage of computational efficiency compared to the standard discontinuous Galerkin methods. Our numerical examples not only support our findings but also show optimal convergence rates in all variables in the L² norm and show that our method performs well with highly discontinous permeability fields in the microfractures and the porous matri
Supporting preschool teachers in assessing Arabic-English dual language learners (dlls) in classrooms using an authentic assessment: a qualitative exploration on the perceptions of teachers and Arab parents
No full textThe purpose of this research was to explore the perceptions of non-Arab preschool teachers’ experiences in assessing Arabic-English dual language learners (DLLs) in classrooms using a well-established, teacher scored authentic assessment of early childhood holistic development. Moreover, this study explored parents’ experiences by discussing these assessments and their perceptions of their role in supporting their child’s development. Qualitative interviews were used to collect data from non-Arab teachers and Arab parents to gain a deeper understanding of how teachers assess their Arab preschoolers, what helpful practices they use, and what challenges they face, as well as Arab parents’ perceptions of their children’s development. A total of 16 participants were interviewed, including eight non-Arab preschool teachers and eight Arab parents, from five schools located in different cities across Michigan in the United States. A grounded theory approach was used to analyze the data and generate main themes to address the research questions. Findings indicated that non-Arab preschool teachers face challenges in assessing Arabic-English DLLs. The main challenge was understanding what the child is trying to say when he/she uses Arabic words in his/her answer. The second main challenge was teachers not recognizing structural differences in Arabic and English, such as writing direction, which could lead to inaccurate assessment scoring. Successful practices that preschool teachers used to raise the level of accuracy of the child’s scores, included multiple observations, different forms of communication, like nonverbal communication, learning Arabic words themselves, and engaging families more. The present study points to the importance of teacher-parent communication and the importance of professional development for teachers on Arabic language and culture to help them better understand and engage with their Arab students. Future research may be a longitudinal study with a wider range of Arab nationalities
“It’s Kinda Cool that You Came to My House.” An Exploratory Study of Home Visits in a Rural Public School
No full textThe exploratory study examined the outcomes of home visits conducted in primary grades of a Midwest rural public elementary school. The research considered both quantitative and qualitative data on teacher and caregiver relationship, teacher and student relationship, student academic success, attendance data, and behavioral changes. The participants included teachers, caregivers, and students. The research was completed over the 2022-2023 school year. The major finding of the research was the support that caregivers and teachers had for the development of the student and teacher relationships for the educational success of the student. Another finding was the support for home visits from both teachers and caregivers as an educational strategy. Additional research to expand on this exploratory study was suggested to further examine the themes and results for larger program implementation
Understanding the lived experiences of Saudi Arabian international students in the United States during the first strike of the COVID-19 pandemic: a phenomenological study
No full textThis research aimed to explore the lived experiences of Saudi Arabian international students studying in the United States during the first strike of the coronavirus (COVID-19) pandemic. Three research questions guided my study: What challenges did Saudi Arabian international students studying in the United States experience at the onset of the COVID-19 pandemic? What type of support or services did the students receive from their institutions or the government? How did the students cope and adjust as the COVID-19 pandemic persisted? This research applied segmented assimilation theory to the students' integration theory and drew on higher education research literature to suggest some indicators that could be employed to study international students' perceptions of their higher education experiences. The aim was to gain a deeper understanding of students' experiences from underrepresented groups better. I employed a qualitative research design to develop an understanding and identify common challenges Saudi Arabian international students experienced during the first strike of the coronavirus pandemic. I collected data from 10 participants by conducting in-depth phenomenological interviews. I developed the interview protocol with a list of semi-structured interview questions prepared in advance and used to guide the interviews. The findings revealed six major themes: (a) Financial impact, (b) Impact on academic life, (c) Institutional communication and support, (d) Impact on social life and social support, (e) Emotional and psychological impact and support, and (f) Strategies for adaptation and persistence. The themes from the participants' experiences revealed intersections with and ties to the scholarly literature. My research developed an understanding of the perspectives expressed by Saudi Arabian international students in the early stages of the COVID-19 pandemic. Understanding the lived experiences of underrepresented groups is crucial for policymakers and regulators, as well as for those developing support initiatives, to effectively serve these populations. The recommendations for future research and professionals provide a clear direction in developing support programs for international students and enhancing the services provided to them, with the aim of promoting their well-being and facilitating their progres