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Title: Towards discrete-pulse-based networking and event detection architectures for resource-constrained applications
Creator: Das, Saptarshi (Graduate of Michigan State University)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "In this dissertation thesis, we develop a scalable and energy-efficient discrete-pulse-based networking architecture along with a Spiking-Neuron-based low-power detection framework for use in resource-constrained settings. Applications such as Structural Health Monitoring (SHM) using wireless sensor networks powered by ambient energy harvesting are particularly suited for such a framework. The key idea in pulse-based networking is to eschew unnecessary overhead as incurred in traditional...
Show more"In this dissertation thesis, we develop a scalable and energy-efficient discrete-pulse-based networking architecture along with a Spiking-Neuron-based low-power detection framework for use in resource-constrained settings. Applications such as Structural Health Monitoring (SHM) using wireless sensor networks powered by ambient energy harvesting are particularly suited for such a framework. The key idea in pulse-based networking is to eschew unnecessary overhead as incurred in traditional packet-based networking and encode only the essential information using small number of discrete pulses and their positions with respect to a synchronized time frame structure. The baseline pulse networking does not scale well with increase in network size. In order to ameliorate this, we develop a scalable time frame structure for use in applications with large network size while preserving the energy advantages of pulse networking. In addition, we stress the importance of judicious use of erratic energy availability in ambient energy harvesting powered systems. To that effect, we build energy-awareness syntaxes within the pulse networking framework for better utilization of energy resources in such systems. We also demonstrate the feasibility of pulse networking over a through-substrate ultrasonic link layer and the advantages thereof in terms of utilizing existing infrastructure and removing the need for radio retrofits. We explore how the protocol performance varies for an airplane stabilizer monitoring application powered by ambient vibration energy harvesting in different energy availability scenarios. Beyond this, we also develop a Spiking-Neuron-based low-power event pattern detection architecture and illustrate how this can be incorporated within a pulse-networked SHM system. The Spiking Neuron based architecture is evidenced to be simpler in terms of implementation but more efficient in terms of computation and energy usage, thus enabling in-situ detection even at intermediate nodes in the network and robust low-power event pattern detection immune to pulse drifts and errors."--Pages ii-iii.
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Title: Towards a community of practice for an informed citizenry : secondary students' sense-making of graphs related to climate change
Creator: Lee, May H.
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Although graphs are used to communicate much of the science-based issues that impact our society (e.g., climate change), citizens often do not make sense of them as intended. To help people become members in a community of competent outsiders, this qualitative study investigates how my participants made sense of three graphs depicting phenomena related to climate change (Keeling, Temperature, and Arctic). The analysis of my participants' interview transcripts and sketches showed that their...
Show moreAlthough graphs are used to communicate much of the science-based issues that impact our society (e.g., climate change), citizens often do not make sense of them as intended. To help people become members in a community of competent outsiders, this qualitative study investigates how my participants made sense of three graphs depicting phenomena related to climate change (Keeling, Temperature, and Arctic). The analysis of my participants' interview transcripts and sketches showed that their sense-making of these graphs could be characterized by one of four approaches (figurative, literal, analytic, and analytic+) with respect to the graphing practices (interpret and analyze, explain, predict, and generalize) and set of crosscutting strategies (stories about how phenomena occur, mathematical strategies, and perceptions of graph sources and uses). The general framework for the graphical sense-making of these three graphs can be used to inform curriculum development, classroom instruction, and assessment design of concepts and practices related to those graphs.
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Title: Towards a Robust Unconstrained Face Recognition Pipeline with Deep Neural Networks
Creator: Shi, Yichun
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Face recognition is a classic problem in the field of computer vision and pattern recognition due to its wide applications in real-world problems such as access control, identity verification, physical security, surveillance, etc. Recent progress in deep learning techniques and the access to large-scale face databases has lead to a significant improvement of face recognition accuracy under constrained and semi-constrained scenarios. Deep neural networks are shown to surpass human performance...
Show moreFace recognition is a classic problem in the field of computer vision and pattern recognition due to its wide applications in real-world problems such as access control, identity verification, physical security, surveillance, etc. Recent progress in deep learning techniques and the access to large-scale face databases has lead to a significant improvement of face recognition accuracy under constrained and semi-constrained scenarios. Deep neural networks are shown to surpass human performance on Labeled Face in the Wild (LFW), which consists of celebrity photos captured in the wild. However, in many applications, e.g. surveillance videos, where we cannot assume that the presented face is under controlled variations, the performance of current DNN-based methods drop significantly. The main challenges in such an unconstrained face recognition problem include, but are not limited to: lack of labeled data, robust face normalization, discriminative representation learning and the ambiguity of facial features caused by information loss.In this thesis, we propose a set of methods that attempt to address the above challenges in unconstrained face recognition systems. Starting from a classic deep face recognition pipeline, we review how each step in this pipeline could fail on low-quality uncontrolled input faces, what kind of solutions have been studied before, and then introduce our proposed methods. The various methods proposed in this thesis are independent but compatible with each other. Experiment on several challenging benchmarks, e.g. IJB-C and IJB-S show that the proposed methods are able to improve the robustness and reliability of deep unconstrained face recognition systems. Our solution achieves state-of-the-art performance, i.e. 95.0\% TAR@FAR=0.001\% on IJB-C dataset and 61.98\% Rank1 retrieval rate on the surveillance-to-booking protocol of IJB-S dataset.
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Title: Toward a sustainable online Q&A community via design decisions based on individuals' expertise : evidence from simulations
Creator: Liang, Yuyang
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Online Q&A communities have become an important channel for internet users to seek information and share knowledge. Existing research extensively focuses on the individual components of Q&A communities, such as content quality and user characteristics, but fails to provide a comprehensive understanding of the communities as complex social systems, whose behavior depends on the interactions of a large number of social agents. In this dissertation, I integrated the key components in online Q&A...
Show moreOnline Q&A communities have become an important channel for internet users to seek information and share knowledge. Existing research extensively focuses on the individual components of Q&A communities, such as content quality and user characteristics, but fails to provide a comprehensive understanding of the communities as complex social systems, whose behavior depends on the interactions of a large number of social agents. In this dissertation, I integrated the key components in online Q&A communities via agent-based modeling to provide a systematic examination of Q&A communities and help inform better community design to manage users' expertise. I conducted computer simulations and virtual experiments based on existing findings and theories as well as data from a large online Q&A community to understand how two design decisions, including expertise indication and question routing, influence the sustainability of a Q&A community as well as result in possible trade-offs involved in implementing these design decisions. Results indicate that these design decisions are likely to lead to a larger membership size and a higher rate of solved questions. In addition, implementing design decisions will also influence the member structure of a community. Question routing tends to prioritize experts' needs and benefits while expertise indication is more likely to attract beginners. These findings suggest that these design decisions should be leveraged according to the development stage a community is in. This research also demonstrates the value of agent-based modeling in terms of generating insights for Q&A community design by showing the underlying structural outcomes of the design decisions.
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Title: Topical outline of highway traffic control
Creator: Ireland, Mark L.
Date: 1924
Collection: Electronic Theses & Dissertations

Title: Tool Wear Study in Turning Ti-6Al-4V and Edge Trimming of Carbon Fiber Reinforced Plastics (CFRP)
Creator: Khawarizmi, Ryan Muhammad
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Lightweight materials such as titanium alloys and carbon fiber reinforced plastics (CFRP) are highly desirable due to their low density and high strength properties for many aerospace, chemical, petroleum, automotive, and sports applications. However, both materials are considered difficult to machine due to various factors.In machining titanium alloys, the low thermal conductivity and highly reactive nature of titanium with cutting tools cause the temperature to rise quickly, producing a...
Show moreLightweight materials such as titanium alloys and carbon fiber reinforced plastics (CFRP) are highly desirable due to their low density and high strength properties for many aerospace, chemical, petroleum, automotive, and sports applications. However, both materials are considered difficult to machine due to various factors.In machining titanium alloys, the low thermal conductivity and highly reactive nature of titanium with cutting tools cause the temperature to rise quickly, producing a segmented or “saw-tooth” chip. Chip segmentation caused a periodic loading on the tool and affected the cutting process. Ti-6Al-4V depending on the heat treatment, produces four distinct types, elongated (ELO), mill-annealed (MIL), solution treated and aged (STA), and lamellar (LAM). In this dissertation, four different microstructures of Ti64, ELO, MIL, STA, and LAM, are machined at 61, 91, and 122 m/min. The machining chips were collected and characterized to study the impact of the microstructure. In addition, the crater wear for different types of Ti64 was measured and compared. A finite element numerical simulation was developed using the chip morphology measured, which enables estimating the cutting temperature for Ti64-STA. Electron backscatter images of the cutting chips (EBSD) and crater wear surfaces were also analyzed to verify the wear mechanism. The findings suggested a high interface temperature during cutting enables faster tool diffusion. Another machinability study of turning Ti64-STA using a variety of coated tools was conducted. The coated tool materials include TiAlN, AlTiN, AlMgB14(BAM), ZrN, and (AlCrSi/Ti)N. The performance of these cutting tools was assessed using cutting force data, flank wear, and crater wear measurements. In conjunction with the coating experiments, another machining study was conducted in minimum quantity lubrication (MQL) using oil mixed with solid additives such as hBN, WS2, MoS2, and xGnP. For CFRP, the abrasion from the fibers was the leading cause of tool wear. Three distinctly different types of CFRPs with T300 PAN-based carbon fibers as standard modulus (SM), IM-7 PAN-based carbon fibers as intermediate modulus (IM), and K13312 pitch-based carbon fibers as high modulus (HM) are used. Tool wear during the edge-trimming process of three types of CFRP laminates is analyzed for four different ply angles, namely 0°, 45°, 90°, 135°, to investigate the interactions between the fiber type and the fiber orientation.
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Title: To translate a life : understanding the holocaust through autobiographical stories
Creator: Stieren, Amelia Naomi
Date: 2020
Collection: Electronic Theses & Dissertations
Description: This thesis seeks to understand some of the aspects and events of the Holocaust through autobiographical stories, with a particular focus on what it means to translate one's life. As there are many different ways one can learn about the Holocaust, this thesis takes a comparative approach of the works of two authors with very different life circumstances: Ruth Kluger's autobiographical works weiter leben: Eine Jugend, and Still Alive: A Holocaust Girlhood Remembered, and Nora Krug's graphic...
Show moreThis thesis seeks to understand some of the aspects and events of the Holocaust through autobiographical stories, with a particular focus on what it means to translate one's life. As there are many different ways one can learn about the Holocaust, this thesis takes a comparative approach of the works of two authors with very different life circumstances: Ruth Kluger's autobiographical works weiter leben: Eine Jugend, and Still Alive: A Holocaust Girlhood Remembered, and Nora Krug's graphic memoirs Belonging: A German Reckons with History and Home, and Heimat: Ein deutsches Familienalbum. While both authors have in common that they have written their works in both English and German, the lives of these authors are remarkably different: Ruth Kluger is a Jewish survivor of the genocide from Austria, living in the United States, and Nora Krug is neither a survivor nor Jewish, but rather, a German living in the United States with familial ties to Nazi Germany. Nevertheless, in the translation of their lives into their works, both authors raise many questions and concerns about their identity, displacement (forced for Kluger, chosen for Krug), their sense or lack of belonging, and how different aesthetic forms are necessary for them in the constructing of their life narratives, and in tandem with each other, they offer a way to further understand the events of the Holocaust.
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Title: To epenthesize or not? segment insertion in mandarin loanwords
Creator: Huang, Ho-Hsin
Date: 2020
Collection: Electronic Theses & Dissertations
Description: This dissertation investigates segment insertion through two contextualized loanword adaptation processes: intervocalic nasal and coda [m] adaptations, with corpus and experimental data. My research focuses are: 1) to identify the phonological environments of segment insertion in the target adaptation processes in my corpus data, and propose explanations for the insertion patterns in Standard Mandarin loanwords; 2) to verify my arguments with experimental data; 3) to examine whether...
Show moreThis dissertation investigates segment insertion through two contextualized loanword adaptation processes: intervocalic nasal and coda [m] adaptations, with corpus and experimental data. My research focuses are: 1) to identify the phonological environments of segment insertion in the target adaptation processes in my corpus data, and propose explanations for the insertion patterns in Standard Mandarin loanwords; 2) to verify my arguments with experimental data; 3) to examine whether bilingualism affects target segment adaptations; and 4) to discuss what linguistic mechanism controls the adaptation processes.Nasal insertion in Mandarin loanwords is considered an "unnecessary repair" since both English and Mandarin allow a syllable containing consonant-vowel-nasal. However, the existing loanwords show that nasal insertion has strong correlation to the prenasal vowel quality, and the primary word stress location in the source language. To trigger nasal insertion, the English prenasal vowel has to be lax (vowel type condition) and must bear the primary word stress (stress location condition), e.g. Denis → [tan.ni02D0.s02790329]. Nasal insertion rarely occurs when the prenasal vowel is tense or a diphthong, e.g. 02C8Lina → [li02D0.na02D0]. Variable adaptation occurs when the prenasal vowel is [0259], e.g. 02C8Tiffany →[ti02D0.fan.nei] 0303 [ti02D0.fu02D0.ni02D0]. Low back [0251] never triggers nasal insertion, e.g. Ca02C8bana → [kha02D0.pa02D0.na02D0]. I propose that adaptors are sensitive to the fine acoustic cues of the prenasal vowel and stress syllabification pattern. I argue that the "unnecessary repair" is necessary for acoustic cue mapping so the input is perceptually similar to the output.Vowel epenthesis is argued to fix illicit coda [m] in Mandarin, but it is related to syllable location and the following consonant type. It occurs in word-medial and word-final coda positions. It never occurs in homorganic environments with a prenasal lax vowel, e.g. Columbia → [k026402D0.lun.pi02D0ja02D0]. However, with a prenasal diphthong or tense vowel, vowel epenthesis still appears. Variable adaptation is present when coda [m] is in word-medial position followed by an obstruent, e.g. Camden → [kha02D0.mu02D0.t0259n] 0303 [kh0259n.tun]. I propose that vowel epenthesis takes place to preserve all the segmental information, although the output may be perceived as less similar to the input due to an excess vowel. Repairing with [n]/[n] in homorganic environments not only preserves all the underlying features but also leads the output to be more perceptually similar to the input. Both modification methods suggest that coda [m] adaptation is motivated by phonological grammaticality, and acoustic cues play a relatively minor role.33 Mandarin monolingual and 24 Mandarin-English bilingual speakers participated in the experiments. Test item structures followed the corpus generalizations. For intervocalic nasal adaptation, the results from both groups are similar to each other and to the corpus data patterns: participants were sensitive to prenasal vowel quality. Similar results from the two groups further confirm that nasal insertion is more phonetically driven. For coda [m] adaptation, the results from the bilingual participants follow the Preservation Principle, even in homorganic lax vowel environments. The monolinguals repair the coda [m] through epenthesis and nasal place change by chance. I suggest that the coda [m] adaptation process is phonologically driven.This dissertation demonstrates that nasal adaptations in Standard Mandarin are contextualized. Two adaptation processes with essential differences in grammaticality are controlled by different linguistic mechanisms. Intervocalic nasal adaptation supports the perception-based loanword model, whereas coda [m] adaptation supports the phonology-based model.
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Title: To determine the best proportion of old & new carbonizers for case hardening steel
Creator: Millard, Forrest Gass
Date: 1919
Collection: Electronic Theses & Dissertations

Title: Time-domain analysis of fractional wave equations and implementations of perfectly matched layers in nonlinear ultrasound simulations
Creator: Zhao, Xiaofeng
Date: 2018
Collection: Electronic Theses & Dissertations
Description: The attenuation of ultrasound propagating in human tissue follows a power law with respect to frequency that is modeled by several different fractional partial differential equations. These models for the power law attenuation of medical ultrasound have been developed using fractional calculus, where each contains one or more time-fractional or space-fractional derivatives. To demonstrate the similarities and differences in the solutions to causal and noncausal fractional partial differential...
Show moreThe attenuation of ultrasound propagating in human tissue follows a power law with respect to frequency that is modeled by several different fractional partial differential equations. These models for the power law attenuation of medical ultrasound have been developed using fractional calculus, where each contains one or more time-fractional or space-fractional derivatives. To demonstrate the similarities and differences in the solutions to causal and noncausal fractional partial differential equations, time-domain Green's functions are calculated numerically for the fractional wave equations. For three time-fractional wave equations, namely the power law wave equation, the Szabo wave equation, and the Caputo wave equation, these Green's functions are evaluated for water with a power law exponent of y=2, liver with a power law exponent of y=1.139, and breast with a power law exponent of y=1.5. Simulation results show that the noncausal features of the numerically calculated time-domain response are only evident in the extreme nearfield region and that the causal and the noncausal Green's functions converge to the same time-domain waveform in the farfield. When noncausal time-domain Green's functions are convolved with finite-bandwidth signals, the noncausal behavior in the time-domain is eliminated, which suggests that noncausal time-domain behavior only appears in a very limited set of circumstances and that these time-fractional models are equally effective for most numerical calculations.For the calculation of space-fractional wave equations, time-domain Green's functions are numerically calculated for two space-fractional models, namely the Chen-Holm and Treeby-Cox wave equations. Numerical results are computed for these in breast and liver. The results show that these two space-fractional wave equations are causal everywhere. Away from the origin, the time-domain Green's function for the dispersive Treeby-Cox space-fractional wave equation is very similar to the time-domain Green's functions calculated for the corresponding time-fractional wave equations, but the time-domain Green's function for the nondispersive Chen-Holm space-fractional wave equation is quite different. To highlight the similarities and differences between these, time-domain Green's functions are compared and evaluated at different distances for breast and liver parameters. When time-domain Green's functions are convolved with finite-bandwidth signals, the phase velocity difference in these two space-fractional wave equations is responsible for a time delay that is especially evident in the farfield.The power law wave equation is also utilized to implement a perfectly matched layer (PML) for numerical calculations with the Khokhlov - Zabolotskaya - Kuznetsov (KZK) equation. KZK simulations previously required a computational grid with a large radial distance relative to the aperture radius to delay the reflections from the boundary. To decrease the size of the computational grid, an absorbing boundary layer derived from the power law wave equation. Simulations of linear pressure fields generated by a spherically focused transducer are evaluated for a short pulse. Numerical results for linear KZK simulations with and without the absorbing boundary layer are compared to the numerical results with a sufficiently large radial distance. Simulation results with and without the PML are also evaluated, where these show that the absorbing layer effectively attenuates the wavefronts that reach the boundary of the computational grid.
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Title: Time-dependent description of heavy-ion collisions
Creator: Lin, Hao (Graduate of Michigan State Univesity)
Date: 2020
Collection: Electronic Theses & Dissertations
Description: In this thesis, we aim to advance the time-dependent transport theories for the description of heavy-ion collisions, from two perspectives. As an attempt to address multifragmentation in nuclear collisions, we develop a stochastic transport model based on one-body Langevin dynamics. The new model is subsequently tested and benchmarked with a series of other existing models with satisfaction. The model is also applied to address and confirm the so-called "hierarchy effect" observed in the...
Show moreIn this thesis, we aim to advance the time-dependent transport theories for the description of heavy-ion collisions, from two perspectives. As an attempt to address multifragmentation in nuclear collisions, we develop a stochastic transport model based on one-body Langevin dynamics. The new model is subsequently tested and benchmarked with a series of other existing models with satisfaction. The model is also applied to address and confirm the so-called "hierarchy effect" observed in the multifragmentation for certain systems around Fermi energies. Parallel to the development towards a stochastic theory, we also extend an approach based on non-equilibrium Green's function for the description of correlated nuclear systems in one dimension.Firstly, we present a new framework to treat the dissipation and fluctuation dynamics associated with nucleon-nucleon scattering in heavy-ion collisions. The two-body collisions are effectively described in terms of the diffusion of nucleons in viscous nuclear media, governed by a set of Langevin equations in momentum space. The new framework combined with the usual mean-field dynamics, forming the basis of the new stochastic model, can be used to simulate heavy-ion collisions at intermediate energies.Subsequently, as a proof of principle for the new model, we simulate Au + Au reactions 100 MeV/nucleon and at 400 MeV/nucleon and look at observables such as rapidity distribution and flow as a function of rapidity. The results are found to be consistent with other existing models under the same constrained conditions. To demonstrate the model's ability to describe multifragmentation, we also study the formation of fragments in Sn +Sn reactions at 50 MeV/nucleon, and the fragment distribution and properties are discussed and compared to two other models commonly employed for collisions.Next, we move on to tackle the "hierarchy effect" observed experimentally for reactions around Fermi energies. We simulate Ta + Au at 39.6 MeV/nucleon and compare mainly the charge and velocity distributions of the fragments from the QP with experimental data. Our simulation results can reproduce the trends observed in data, and a semi-quantitative agreement can be reached. This is the first time, to our knowledge, that one has succeeded in addressing the "hierarchy effect" with a dynamic model. The simulation of U + C is also discussed.Finally, we present a fully quantum-mechanical model based on non-equilibrium Green's function, with short-range two-body correlations incorporated as an extension. We examine its applications to one-dimensional nuclear systems, such as the preparation and properties of the ground states, the isovector oscillation of symmetric systems and the boosting of a"slab" in a periodic box. In particular, the dissipation brought by two-body correlations and the Galilean covariance of the theory are demonstrated. These studies lay the groundwork for the future exploration of collisions of correlated nuclear systems in one dimension.
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Title: Timber residue supply for bioenergy in the northern tier of the Great Lakes : determinants and availability
Creator: Dulys-Nusbaum, Elena
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Timber residues, a timber byproduct, are a low-cost source of biomass that avoids the environmental and food market consequences of other energy feedstocks. We studied the effect that price, forest species mix, bio-energy attitudes, environmental amenities, and environmental disamenities have on the decision to harvest for non-industrial private forest owners (NIPFs) in northern Michigan and Wisconsin."--from abstract.

Title: Tile drainage system for the farm of F.C. Brainerd
Creator: Brainerd, Walton K.
Date: 1899
Collection: Electronic Theses & Dissertations

Title: Through experiences, from interactions, and by choices over time : how professors at a research university understand and explain the factors that have influenced their teaching
Creator: Steele, Gregory John
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The intent of this study was to understand professors at a research university, and how the environments and individuals they interact with influenced them and their teaching. The primary research question for this study was, "How do professors at a research university understand and explain the factors that have influenced their teaching?" The secondary research question was intended to focus on the institutional factors that had the most influence on a professor and their teaching: "What...
Show moreThe intent of this study was to understand professors at a research university, and how the environments and individuals they interact with influenced them and their teaching. The primary research question for this study was, "How do professors at a research university understand and explain the factors that have influenced their teaching?" The secondary research question was intended to focus on the institutional factors that had the most influence on a professor and their teaching: "What are the most influential factors that affect a professor's teaching at a research institution?"I interviewed 15 award-winning professors from Michigan State University (MSU) about how they had been prepared, supported, and recognized for their work as teachers. My analysis showed how little preparation the professors received about teaching at a research university, how they relieved more on experience and trusted peers than any of the available campus resources, and how they tended to find personal student recognition more rewarding than their prestigious teaching awards. My results showed how institutional deficiencies (the lack teaching preparation, applicable resources, and sufficient recognition) created obstacles for the professors to overcome as they progressed and developed as teachers. To lessen or remove the institutional obstacles, I recommend research universities better assess and recognize a professor's teaching, faculty developers localize their available resources to the individual colleges and departments, and professors utilize their peers and self-reflection as a way to meet their needs and expectations as teachers. Professors at research universities are expected to prioritize their teaching and scholarship, but the importance of the former can become complicated when institutions place a greater emphasis on the latter (via the tenure process, promotions, raises, and rewards). This study extends previous scholarship which shows that professors at research universities are not sufficiently prepared, supported, or recognized for their work as teachers. If the individual institutions do not properly prepare their professors as teachers, then there is uncertainty as to how, where, and why the individual professors succeed and develop as teachers.
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Title: Three essays on the causes and consequences of youth migration in Tanzania
Creator: Moskaleva, Evgeniya Alekseevna
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Migration of youth is a prominent phenomenon in Sub-Saharan Africa and in East Africa in particular. International and rural-to-urban migration gained a lot of attention in the older literature, yet internal rural-to-rural migration is the most frequent type. This work revolves around several issues of internal migration of youth in rural Tanzania. First, I determine which factors are associated with destination decisions made by young people. I look at four to six destination types on the...
Show moreMigration of youth is a prominent phenomenon in Sub-Saharan Africa and in East Africa in particular. International and rural-to-urban migration gained a lot of attention in the older literature, yet internal rural-to-rural migration is the most frequent type. This work revolves around several issues of internal migration of youth in rural Tanzania. First, I determine which factors are associated with destination decisions made by young people. I look at four to six destination types on the rural-urban spectrum and consider various individual, household, and community factors that could affect migration decision. Second, I test how does migration to various destination areas on the rural-urban spectrum contribute to structural transformation through the shifts in main occupation. Although focusing on the shifts from agricultural work to self-employment and wage job, I also consider other employment categories like students, those working mainly in household maintenance, and unemployed people. Third, I estimate the impacts of youth outmigration on the livelihood of non-migrant household members. I consider changes to the labor supplied to the household farm, attraction of new household members, and adjustments to household participation in labor and land markets.I make contribution to the literature on internal migration of youth in Sub-Saharan Africa, and Tanzania in particular, in four ways. First, I distinguish several migration destinations across the rural-urban spectrum, from low-density rural areas to cities, broadening the conceptualization of migration decision instead of focusing on a specific flow of migrants. I test three categorizations of location types to account for different interpretations of results and to verify that the main results are not an artifact of the choice of the definition of “rural”. Second, I stress the importance of rural-to-rural migration, which is prevalent in Tanzania, although understudied. I show that even migration to low-density rural areas is associated with a shift towards non-agricultural employment. Third, while looking at occupational shifts, I consider people who are usually excluded from the analysis: students and those employed in household maintenance. I also look at women who state marriage as their main reason for migration. It allows to broaden the view on migration flows and discover employment difficulties for certain groups of people, for example, female rural-to-rural migrants involved mainly in household maintenance and students transitioning into employment. Fourth, I explore the labor adjustment strategies of the households left behind after a young adult migrates, which has rarely been studied in the context of the countries of Sub-Saharan Africa.
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Title: Three essays on multi-stakeholder school governance : participation of parents, local communities and private partners in school management and finance
Creator: Sakamoto, Jutaro
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Education decentralization facilitates the participation of parents, local communities, and private partners in school management and finance, forming a system of multiple-stakeholder school governance. While their participation is expected to hold a school accountable for educational outcomes, engaging external stakeholders who are not education professionals and who have diverging interests may have adverse effects. Does the participation of external stakeholders in school management and...
Show moreEducation decentralization facilitates the participation of parents, local communities, and private partners in school management and finance, forming a system of multiple-stakeholder school governance. While their participation is expected to hold a school accountable for educational outcomes, engaging external stakeholders who are not education professionals and who have diverging interests may have adverse effects. Does the participation of external stakeholders in school management and finance improve educational outcomes? Whose participation really counts? What conditions need to be met to realize the purported positive effects of multiple-stakeholder governance? I examine these questions in three studies.The first study explores efficiency-equity tradeoff of engaging non-state stakeholders in public school finance. Financing public schools with private funds is expected to promote efficient use of resources while it raises concern for financial equity. However, private funds raised from different non-state stakeholders may have differential efficiency and equity effects. Using public school data derived from the Learning and Educational Achievements in Punjab Schools (LEAPS) in Pakistan, this study examines how private funds mobilized from parents, local communities, and private donors are associated with the efficiency of generating student achievement and the equity in school finance. The findings inform the importance of understanding effects of private-fund revenue that vary by its source and school type. This helps design cost-sharing policy that improves both school efficiency and financial equity.The second study explores factors that facilitate or constrain the influence of parents and private partners on school decision-making. Parents and private partners are increasingly engaged in school management as a means to improve education quality and outcomes. In multi-stakeholder school governance, external stakeholders are considered to be able to influence school decisions when their interests and concerns become elevated over the priorities and demands of other parties. This raises a question: under what conditions do their influence become salient? I used the stakeholder salience theory as a conceptual framework to identify factors affecting the influence of parents and private partners on school decision-making through a systematic literature review. The findings were applied to participatory school governance in Pakistan to examine how these factors affect the influence of external stakeholders in a particular context. Based on the analysis, I present a new framework that addresses the multi-dimensional and interrelated nature of stakeholder influence in multi-stakeholder school governance.The third study explores the association between parent participation in school management and student achievement in eight countries and economies. Engaging parents in school management is expected to hold the school accountable for educational outcomes. However, the evidence has proven inconclusive and limited in explaining mechanisms of learning gain/loss. Using the public school student data derived from the Program for International Student Assessment (PISA) 2015, this study examines the association between student achievement and participation of a student's own parents in school management, which would affect their learning support at home, and the participation of a parent group, which would influence school decisions and thus affect the learning environment at school. The findings suggest the importance of identifying which mechanism accounts for positive/negative associations in order to design effective participatory school governance models.
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Title: Three essays in applied economics
Creator: Baker, Quinton James
Date: 2020
Collection: Electronic Theses & Dissertations
Description: My dissertation covers areas in applied economics: labor economics, public economics, and the economics of education. I use a variety of econometric tools and other economic analysis to study welfare program rules and regulations as well as assess the efficacy of a high school science curriculum. My first chapter uses data from the Survey of Income and Program Participation (SIPP), spanning 2003-2013, to estimate whether the ABAWD-specific 20 hour per week minimum work requirement influences...
Show moreMy dissertation covers areas in applied economics: labor economics, public economics, and the economics of education. I use a variety of econometric tools and other economic analysis to study welfare program rules and regulations as well as assess the efficacy of a high school science curriculum. My first chapter uses data from the Survey of Income and Program Participation (SIPP), spanning 2003-2013, to estimate whether the ABAWD-specific 20 hour per week minimum work requirement influences their labor supply outcomes and SNAP participation. I employ binary response models to estimate average partial effects (APE) and find the work requirement has statistically significant effects: ABAWDs are 1 percentage point (pp) less likely to participate in SNAP and are 2.6 pp more likely to meet the 20-hourwork requirement. This negative effect of the work requirement on SNAP participation is larger among non-white (1.37 pp), specifically blacks (2.09 pp), suggesting that the impacts of a work requirement must be considered in areas with higher percentages of minorities. This paper contributes to the study of ABAWDs, a relatively understudied population in the context of SNAP.Chapter 2 uses the 2014 Survey of Income and Program Participation (SIPP), spanning from January 2013 to December 2016, to study the effect of SNAP and Medicaid expansion on labor market outcomes (income, hours worked and employment status) and SNAP participation. Using a suite of empirical methods, I find no evidence that the interaction of the SNAP and Medicaid expansions has an effect on labor outcomes of the head and second adult in a household. However, I do find that the Medicaid expansion increases SNAP participation in states with the least generous state-level SNAP policy options. These findings demonstrate the importance of analyzing the effect of both expansions jointly, as both SNAP and Medicaid serve low income households that may simultaneously choose their labor supply and program participation.Chapter 3 uses data from the NSF funded project Crafting Engaging Science Environments(CESE), a cluster-randomized controlled trial to study the effect of project-based learning on the scientific achievement of high school chemistry and physics students in Michigan and California during the 2018-2019 school year. I extend the analysis conducted in Schneideret al. (2021) and use pooled OLS with school level fixed effects to estimate the treatment effect. I find sound evidence to support the findings in Schneider et al., 2021 that the CESE intervention had a positive and significant effect on students' scientific learning, even in the presence of multiple levels of attrition. The point estimates range from 0.24 to 0.34 standard deviations. Additionally, I compute the Lee Bounds for the estimates and find the bounds do not contain zero, suggesting that differential attrition alone likely does not drive the entire treatment effect.
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Title: Three dimensional analysis of the gas flow in piston ring pack
Creator: Kharazmi, Ali
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Cylinder-kit dynamics design in an internal combustion engine is highly relevant for the engine performance characteristics, durability and reliability. Since the middle of the 20th century, researchers have been using numerical models to describe the processes that occur in a ring pack. Because it is difficult and extremely costly to conduct experiments on every series of engines to check for the blow-by and oil consumption, a computational analysis can be performed on the ring pack to...
Show more"Cylinder-kit dynamics design in an internal combustion engine is highly relevant for the engine performance characteristics, durability and reliability. Since the middle of the 20th century, researchers have been using numerical models to describe the processes that occur in a ring pack. Because it is difficult and extremely costly to conduct experiments on every series of engines to check for the blow-by and oil consumption, a computational analysis can be performed on the ring pack to study the blow-by and oil-consumption characteristics. In this dissertation a 3D CFD simulation model is introduced to analyze the flow between the cylinder liner and the piston. This model allows for calculation of the piston assembly with consideration of the ring dynamics, transient boundary conditions for combustion chamber pressure and temperature as well as thermal distortion of the piston and liner. The determination of the complex geometry of the cylinder-kit is established in a STL (STereoLithography) format by considering the complicated geometrical details of the ring pack such as thermal distortion of piston and liner, ring twist and ring/groove conformability. The blow by and blow back is numerically calculated for a small bore cylinder operating at 2000 RPM and verified by the results of commercially available 1D models. The calculated velocity filed shows substantial circumferential flow in the piston ring pack that is dominated by the ring and groove geometry as well as the relative position of the rings end gap. It is found that the amount of gas that flows back to the combustion chamber increases when the in-cylinder pressure trace decreases from its peak value. The knowledge from this study can be used as a basis for further multiphase calculations containing oil flow such as oil consumption, oil evaporation and eventually cylinder-kit wear."--Page ii.
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Title: Three Essays on Panel Data Models with Interactive and Unobserved Effects
Creator: Brown, Nicholas Lynn
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Chapter 1: More Efficient Estimation of Multiplicative Panel Data Models in the Presence of Serial Correlation (with Jeffrey Wooldridge)We provide a systematic approach in obtaining an estimator asymptotically more efficient than the popular fixed effects Poisson (FEP) estimator for panel data models with multiplicative heterogeneity in the conditional mean. In particular, we derive the optimal instrumental variables under appealing `working' second moment assumptions that allow...
Show moreChapter 1: More Efficient Estimation of Multiplicative Panel Data Models in the Presence of Serial Correlation (with Jeffrey Wooldridge)We provide a systematic approach in obtaining an estimator asymptotically more efficient than the popular fixed effects Poisson (FEP) estimator for panel data models with multiplicative heterogeneity in the conditional mean. In particular, we derive the optimal instrumental variables under appealing `working' second moment assumptions that allow underdispersion, overdispersion, and general patterns of serial correlation. Because parameters in the optimal instruments must be estimated, we argue for combining our new moment conditions with those that define the FEP estimator to obtain a generalized method of moments (GMM) estimator no less efficient than the FEP estimator and the estimator using the new instruments. A simulation study shows that the GMM estimator behaves well in terms of bias, and it often delivers nontrivial efficiency gains -- even when the working second-moment assumptions fail.Chapter 2: Information equivalence among transformations of semiparametric nonlinear panel data modelsI consider transformations of nonlinear semiparametric mean functions which yield moment conditions for estimation. Such transformations are said to be information equivalent if they yield the same asymptotic efficiency bound. I first derive a unified theory of algebraic equivalence for moment conditions created by a given linear transformation. The main equivalence result states that under standard regularity conditions, transformations which create conditional moment restrictions in a given empirical setting need only to have an equal rank to reach the same efficiency bound. Example applications are considered, including nonlinear models with multiplicative heterogeneity and linear models with arbitrary unobserved factor structures.Chapter 3: Moment-based Estimation of Linear Panel Data Models with Factor-augmented ErrorsI consider linear panel data models with unobserved factor structures when the number of time periods is small relative to the number of cross-sectional units. I examine two popular methods of estimation: the first eliminates the factors with a parameterized quasi-long-differencing (QLD) transformation. The other, referred to as common correlated effects (CCE), uses the cross-sectional averages of the independent and response variables to project out the space spanned by the factors. I show that the classical CCE assumptions imply unused moment conditions which can be exploited by the QLD transformation to derive new linear estimators which weaken identifying assumptions and have desirable theoretical properties. I prove asymptotic normality of the linear QLD estimators under a heterogeneous slope model which allows for a tradeoff between identifying conditions. These estimators do not require the number of cross-sectional variables to be less than T-1, a strong restriction in fixed-$T$ CCE analysis. Finally, I investigate the effects of per-student expenditure on standardized test performance using data from the state of Michigan.
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Title: Three Essays on Labor Market Regulation in the American Construction Industry
Creator: Hinkel, Matthew Phillip
Date: 2022
Collection: Electronic Theses & Dissertations
Description: This three-article dissertation focuses on labor market regulation in the American construction industry.

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