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Title: PLANNING FOR AUTONOMY AND ELECTRIFICATION IN FUTURE TRANSPORTATION SYSTEMS
Creator: Singh, Harprinderjot
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Autonomous vehicles (AVs) and electric vehicles (EVs) will improve safety, mobility, roadway capacity and provide efficient driving, efficient use of travel time, and reduced emissions. However, these technologies affect vehicle miles traveled (VMT), travel time, ownership cost, and electric grid network. Shared mobility systems can ameliorate the high price of these technologies. However, the shared mobility system poses additional problems such as users’ waiting time, inconvenience, and...
Show moreAutonomous vehicles (AVs) and electric vehicles (EVs) will improve safety, mobility, roadway capacity and provide efficient driving, efficient use of travel time, and reduced emissions. However, these technologies affect vehicle miles traveled (VMT), travel time, ownership cost, and electric grid network. Shared mobility systems can ameliorate the high price of these technologies. However, the shared mobility system poses additional problems such as users’ waiting time, inconvenience, and increased VMT. Further, the impact of these emerging technologies varies on different groups of users (different values of travel time (VOTT). Another hurdle to the adoption of EVs is the limited range and scarcity of charging infrastructure. A well-established network of charging infrastructure, especially the direct current fast chargers (DCFC), can alleviate this challenge. However, the widespread adoption of EVs and the growing network of DCFC stations will increase the electric energy demand affecting the electric grid stability, demand-supply imbalance, overloading, and degradation of the electric grid components. Distributed energy resources (DER) such as solar panels and energy storage systems (ESS) can support the EV demand and reduce the load on the electric grid. This study develops modeling frameworks for the optimal adoption of AVs and EVs, considering their effect on transportation systems, the environment, and the electric grid network. Further, it suggests different scenarios that would promote the adoption of these technologies and provide a sustainable and resilient system.This study proposes a multi-objective mathematical model to estimate the optimal fleet configuration in a system of private manual-driven vehicles (PMVs), private AVs (PAVs), and shared AVs (SAVs) while minimizing the purchase and operating costs, time (travel and waiting time), and emission production. SAVs can be the optimal solution with the efficient use of travel time or the purchase price below a certain relative threshold. PAVs can be the optimal solution only if the onboard amenities are improved, lifetime mileage is increased, AV technology is installed in luxurious cars, and adopted by people with high VOTT. The framework is extended to consider different combinations of EVs, AVs, and conventional human-driven vehicles in a private and shared mobility system. The metaheuristics based on genetic and simulated annealing algorithms are developed to solve the large-scale NP-hard nonlinear optimization problem. The model is implemented for the network of Ann Arbor, Michigan. The results suggest that EVs are optimal for the system due to low operating costs and zero tailpipe emissions. Shared autonomous electric vehicles (SAEVs) are the best option for users with low VOTT. Private autonomous electric vehicles (PAEVs) would favor the system if the travel time savings are at least 20% or the price of AV technology is less than one-third of the vehicle price. The study then investigates the optimum investment technology to support the rising energy demand at the DCFC stations and reduce the load on the electric grid network. The different investments include purchasing and installing various ESS (new batteries (NB), second-life batteries (SLB), flywheels), solar panels, electric grid upgrades, and the cost of buying/selling electricity from/to the electric grid. The model is implemented for the DCFC stations supporting the future needs of EV charging demand for urban trips in the major cities of Michigan in 2030. The combination of SLBs and solar panels provides maximum benefits. The total annual and electricity savings are $25,000-$165,000 and $40,000-$300,000 per city.
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Title: DESIGNING DECLINE : THE RECLAMATION OF AN INDUSTRIAL SITE AND THE DESIGN IMPACTS ON ENVIRONMENTAL, SOCIAL AND ECONOMIC RESILIENCE
Creator: Shevela, Brooke
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The abandoned industrial crisis in Michigan, USA calls for the redevelopment of abandoned industrial site areas into functioning public spaces. These neglected spaces develop negative impacts on the surrounding communities regarding aesthetic, safety, economic, and environmental issues. The purpose of this study is to examine the redevelopment of an underused site, especially featuring an industrial site element, and the effects on the nearby community by applying quantitative measures. The...
Show moreThe abandoned industrial crisis in Michigan, USA calls for the redevelopment of abandoned industrial site areas into functioning public spaces. These neglected spaces develop negative impacts on the surrounding communities regarding aesthetic, safety, economic, and environmental issues. The purpose of this study is to examine the redevelopment of an underused site, especially featuring an industrial site element, and the effects on the nearby community by applying quantitative measures. The Michigan Central Station in Detroit, Michigan, USA was selected as a case study. Landscape performance research was applied to quantitively analyze the environmental, social and economic benefits of reclaiming abandoned industrial sites and their inner elements. In this research, findings showed the case study redesign resulted in positive environmental impacts. These impacts included: expanded areas of ecologically valuable land, increases in carbon sequestration, increases in retained stormwater, the use of recycled content and reductions in sulfur dioxide. The case study redevelopment showed impacts on the surrounding economics through savings on water treatment cost through stormwater retention, increases in property values, and job creation. Furthermore, the redesign also impacted social aspects for the surrounding areas including increases in the area of proposed gathering space, safety enhancements, additions of sidewalks and bike lanes, and increases in the area of public open space. In addition, the major findings support the benefits of public physical health by promoting outdoor activities. The findings of this study will help designers and urban planners to see the value in reusing existing industrial sites instead of undergoing the harmful demolition process and eventually lead to a more sustainable community design.
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Title: Teaching Presence in a Fully Online Asynchronous Undergraduate Mathematics Course and its Impact on Social and Cognitive Presence
Creator: Elmore, Robert Andrew
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The number of fully online asynchronous undergraduate mathematics courses is growing rapidly, making it imperative that the instructional choices that are chosen by instructors and their effects on students’ opportunities to learn in the online learning environment be further explored. Therefore, this research aims to understand instructors' choices when teaching an online undergraduate mathematics course, and how these decisions impact students' communication opportunities. This research...
Show moreThe number of fully online asynchronous undergraduate mathematics courses is growing rapidly, making it imperative that the instructional choices that are chosen by instructors and their effects on students’ opportunities to learn in the online learning environment be further explored. Therefore, this research aims to understand instructors' choices when teaching an online undergraduate mathematics course, and how these decisions impact students' communication opportunities. This research organized the instructors' decisions and their impacts on students using the community of inquiry framework. The three categories of the community of inquiry framework, teaching presence, social presence, and cognitive presence, were analyzed through course artifacts, an instructor interview, student interviews, student surveys, and course usage data. The primary analysis was performed using the interviews with the other data sources providing further detail and explanation. Four claims were generated while analyzing these data sources. Claim one posits that students tend to have singular preferences of the course’s direct instructional elements. Claim 2 proffers that students who chose to work with others report having positive experiences, and those who decided not to work with others report not needing help, with one exception. Claim 3 states that meaningful contact points can be created between the instructor and student using surveys and personalized mass emails; however, most describe learning mathematics in Math 101 as not making them feel a part of a learning community. And claim 4 posits that elements of the teaching presence were more likely to foster participation if they were associated with a grade. The results of this study have implications for both the research and practice communities. The current study’s results imply that—even though sizes of online mathematics classes may still grow—there are ways instructors can facilitate high levels of social processes using mass email, surveys, cooperative learning groups, and other online tools. These specific tools should be studied and evaluated for their effects on social presence and cognitive presence on the mass scale. The present study suggests four specific things that instructors should familiarize themselves with that are available today, (a) prescribe opportunities for students to communicate with each other such as having assignments that are completed in cooperative learning groups, (b) communicate with your students through personalized means (e.g., emails, surveys, and Zoom sessions), (c) use feedback from surveys to inform your future teaching practice, and (d) ensure that students observe your communication and direct instruction by tying them to elements associated with grades. Keywords: teaching presence, social presence, cognitive presence, online mathematics learning.
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Title: DO INTERFACES MATTER? A REEXAMINATION OF XBRL USING FINANCIAL STATEMENT ACQUISITION AND MARKET ACTIVITY
Creator: Anderson, James J.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Starting in 2009 the eXtensible Business Reporting Language (XBRL) standard was mandated for financial statements by the SEC. The XBRL standard was intended to encourage less-sophisticated trader disclosure processing; however, previous literature has conjectured that the standard primarily aided more-sophisticated traders’ disclosure processing. I reexamine the effect of XBRL on more- and less-sophisticated trader disclosure processing by testing whether XBRL influenced their information...
Show moreStarting in 2009 the eXtensible Business Reporting Language (XBRL) standard was mandated for financial statements by the SEC. The XBRL standard was intended to encourage less-sophisticated trader disclosure processing; however, previous literature has conjectured that the standard primarily aided more-sophisticated traders’ disclosure processing. I reexamine the effect of XBRL on more- and less-sophisticated trader disclosure processing by testing whether XBRL influenced their information acquisition and testing whether the proportional relationship between information acquisition and market activity is different for more- and less-sophisticated traders. I find the staggered implementation of XBRL is associated with a 49% (26%) increase in less (more) sophisticated trader information acquisition. Next, I find the proportional relationship between information acquisition and market activity is greater for less-sophisticated traders when compared to more-sophisticated traders. Specifically, I find information acquisition for less-sophisticated traders has a greater proportional relationship with abnormal price movement, abnormal trading volume, and abnormal bid-ask spreads. Together these findings suggest that XBRL did not provide a disproportionate information advantage to more-sophisticated traders, but rather benefited less-sophisticated traders by decreasing their information acquisition costs.
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Title: QUALITY OF LIFE IN CONTEMPORARY NEIGHBORHOOD DESIGN INITIATIVES : AN EMPIRICAL STUDY TO ASSESS QUALITY OF LIFE THROUGH SPATIAL DIMENSION IN NEW URBANIST AND LEED-ND CERTIFIED NEIGHBORHOODS
Creator: Shaaban, Amal Hamdy
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The overarching purpose of this study is to analyze qualitatively and quantitatively the spatial characteristics of two types of neighborhoods, namely New Urbanist (NU) neighborhoods and Leadership in Energy and Environmental Design (LEED) certified neighborhoods. LEED certified neighborhoods are commonly referred to as LEED for Neighborhood Development (LEED-ND). In this research study, the spatial quality of these two types of neighborhoods was examined through assessing the quality of five...
Show moreThe overarching purpose of this study is to analyze qualitatively and quantitatively the spatial characteristics of two types of neighborhoods, namely New Urbanist (NU) neighborhoods and Leadership in Energy and Environmental Design (LEED) certified neighborhoods. LEED certified neighborhoods are commonly referred to as LEED for Neighborhood Development (LEED-ND). In this research study, the spatial quality of these two types of neighborhoods was examined through assessing the quality of five dimensions of a neighborhood’s urban form, which are: safety, comfort, connectivity, place making and aesthetic quality. Three types of neighborhoods were selected and examined using two main analytical tools: neighborhood scorecard, and residents’ survey. Two neighborhoods were selected to examine NU neighborhoods in Michigan in the United States, which are Cherry Hill Village (CHV) a greenfield residential development, and Mason Run (MR) a brownfield residential development. The third neighborhood was selected to examine LEED-ND certified neighborhoods, which is Saint Luke (SL) neighborhood in Ohio in the United States. The neighborhood scorecard included a total of 150 design guidelines that yield better Quality of Life (QoL) in residential developments through urban form. The residents’ survey included a set of questions that examined the residents’ perceptions regarding the five physical characteristics necessary to yield better QoL. A total of 154 surveys were collected for data analysis that used one-way ANOVA tests, Tukey’s post-hoc tests, and multiple regression models. The major findings from the neighborhood scorecard are that CHV neighborhood provides was safer than the brownfield NU residential development and the LEED-ND certified neighborhood. Both NU neighborhoods provided more comfortable environments of their residents to live in more than the LEED-ND certified neighborhood. The greenfield NU neighborhood earned more points than the other two neighborhoods in terms of the internal and external connectivity degree of the neighborhood. In terms of fulfilling the recommended design guidelines for place making and aesthetic quality, again the Greenfield NU neighborhood had earned higher points than the other two neighborhoods. The major findings from the survey are: Survey participants living in both NU neighborhoods were more satisfied with their QoL more than the participants living in the LEED-ND certified neighborhood. Also, respondents living in NU neighborhoods perceived their neighborhoods as safer places to live in more than participants living in the LEED-ND certified neighborhood. On the other hand, respondents living in the NU brownfield development perceived their neighborhood as the least comfortable neighborhood. In terms of the internal connectivity of the neighborhood, respondents living in NU greenfield development identified the internal connectivity of their neighborhood as the highest compared to the other two neighborhoods. On the other hand, the perception of the internal connectivity perception was the lowest amongst respondents living in the LEED-ND certified neighborhood. Respondents living in the LEED-ND certified neighborhood had the highest mean in terms of their perceptions of sense of belonging. On the other hand, respondents living in the NU brownfield development had the lowest mean in terms of their perception of sense of belonging. The perception of the aesthetic quality of the neighborhood was the highest among respondents living in the NU greenfield development. On the other hand, the perception of aesthetic quality of the neighborhood was the least among respondents living in NU brownfield development.This research study concludes by suggesting recommendations to improve the principles and design guidelines of NU and LEED-ND certified neighborhoods to achieve better QoL. The recommendations suggest emphasizing certain spatial characteristics that yield better QoL in Greenfield, and brownfield residential developments.
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Title: Mechanisms underlying Binocular Rivalry
Creator: Jagtap, Abhilasha R.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: When observers view a perceptually bistable stimulus, their perception changes stochastically. Various studies have shown across-observer correlations in the percept durations for different bistable stimuli including Necker cube, binocular rivalry (BR) and bistable moving plaids (MP), which suggests a shared mechanism underlying perception in these paradigms. In this project we explore such shared mechanisms by examining what determines whether a given set of bistable perception paradigms...
Show moreWhen observers view a perceptually bistable stimulus, their perception changes stochastically. Various studies have shown across-observer correlations in the percept durations for different bistable stimuli including Necker cube, binocular rivalry (BR) and bistable moving plaids (MP), which suggests a shared mechanism underlying perception in these paradigms. In this project we explore such shared mechanisms by examining what determines whether a given set of bistable perception paradigms will exhibit correlations in percept durations, and also by examining correlations with other perceptual phenomena that do not directly involve bistability. In our first experiment, we hypothesize that the presence or absence of a certain type of motion can influence whether different bistable paradigms will exhibit correlated percept durations. We found that the correlations between some bistable stimuli are strong, but others are fragile and inconsistent, which prevents us from drawing direct conclusions. In the second experiment, we examine whether between-observer variability in cortical inhibition underlies correlated percept durations between binocular rivalry and bistable moving plaid perception. As a behavioral measure of cortical inhibition, we used center-surround suppression of perceived contrast. While we were able to successfully replicate the correlations between bistable paradigms, there was no correlation between center-surround suppression strength and percept durations for any bistable paradigm. Moreover, the results from a mediation analysis indicate that center-surround suppression is not the mediating factor in the correlation between BR and MP, suggesting that cortical inhibition cannot explain the correlation between various bistable paradigms.
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Title: IMPACTS OF DISTANT DRIVERS ON LANDSCAPES AND BIODIVERSITY
Creator: Hovis, Ciara Layne
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Global biodiversity is increasingly impacted by distant drivers. With societies more connected than ever before, natural resource consumption has expanded beyond administrative and political boundaries. International food trade in particular has profound impacts on land-use and socioeconomic and environmental outcomes. At the same time, global biodiversity is threatened at an unprecedented scale, with many of the causes obfuscated by complexities of distant, interacting socioecological...
Show moreGlobal biodiversity is increasingly impacted by distant drivers. With societies more connected than ever before, natural resource consumption has expanded beyond administrative and political boundaries. International food trade in particular has profound impacts on land-use and socioeconomic and environmental outcomes. At the same time, global biodiversity is threatened at an unprecedented scale, with many of the causes obfuscated by complexities of distant, interacting socioecological systems. Understanding the ultimate drivers of biodiversity change and translating them to local biodiversity outcomes is integral to addressing conservation challenges in the age of globalization. This dissertation analyzes the impacts of international trade on biodiversity in an agroecosystem undergoing land-use change driven by global markets. Chapter 1 provides background on the study region, Heilongjiang Province, and describes disruption of soybean production in the area due to changes in global trade. Chapter 2 is a systematic review of studies on distant drivers of biodiversity change. Across all taxa, harmful impacts on biodiversity were the most frequent outcome reported, with distant impacts of trade and tourism most frequently studied. In Chapter 3, satellite imagery was classified into landcover classes to create high-fidelity maps of the agriculture-dominated study landscape. By utilizing phenological, synthetic aperture radar, and vegetation/soil index data, accuracies of 91%- 80% were achieved. In Chapter 4 these landcover maps were used to calculate landscape metrics. These metrics were then used to analyze relationships between landscape structure (i.e., composition and configuration) and bird communities. Functional biodiversity indices derived from life history and morphological traits were examined in addition to taxonomic measures. Though no discernable differences between taxonomic and functional community metrics were observed, several significant relationships between landscape structure and biodiversity metrics were found. Crop diversity, natural landcover, and edge metrics, were positively correlated with bird richness. Aggregation of patches, corn area, and soybean area were negatively correlated. We also compared landscape structure and biodiversity between two regions impacted by global soybean trade. Despite the more impacted region having lower crop diversity and natural area, there was no difference in biodiversity between the two regions. The more impacted region also had more rice area, demonstrating that negative biodiversity impacts may be mitigated by rice cultivation. Chapter 5 built on the previous chapter by modeling bird occupancy to assess species-specific relationships with landscape structure. Results indicated that increased crop diversity significantly increased occupancy of birds at both the taxonomic and functional level, particularly for birds belonging to less common functional groups. Percentage of natural area was not as important as expected, while metrics related to landscape configuration had very few significant impacts on occupancy. Increases in rice area were not as detrimental to bird occupancy as increases in corn and soybean. In fact, soybean area exhibited more significant negative relationships with bird occurrence than corn, suggesting that decreases in soybean area due to global trade may have benefitted bird biodiversity in the case of a monocultural landscape. However, due to the prevalence of small-scale farming practices, the more likely outcome would be a decrease in crop diversity due to soybean fields being converted to more profitable crops (e.g., corn, rice). By linking global trade, changes in landcover/use, landscape structure, and local bird communities in the same context, the results of this dissertation highlight the need for integrated biodiversity studies that place ecosystems in the broader context of globalization.
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Title: A CASE STUDY EXPLORING HOW K-12 STUDENTS LEARN TO USE SOCIAL MEDIA FOR CIVIC GOOD
Creator: Askari, Emilia Shirin
Date: 2022
Collection: Electronic Theses & Dissertations
Description: This case study explores what K-12 students learn from a 13-week class activity about attracting attention to civic issues on social media. This research responds to calls by scholars of civic education to expand notions of civic engagement and digital citizenship, which often have focused on urging students to protect their reputations in digital spaces. In contrast, the learning activity examined here encourages community-oriented digital citizenship, preparing students to inform and...
Show moreThis case study explores what K-12 students learn from a 13-week class activity about attracting attention to civic issues on social media. This research responds to calls by scholars of civic education to expand notions of civic engagement and digital citizenship, which often have focused on urging students to protect their reputations in digital spaces. In contrast, the learning activity examined here encourages community-oriented digital citizenship, preparing students to inform and possibly empower social change. This study is grounded in Cognitive Flexibility Theory, which focuses on learning in ill-structured domains such as public social media. Further, the study builds on the increasingly popular idea of the Fifth Estate, which posits that people acting in civic ways in public spaces can be a powerful check on government, playing a role similar to that of journalism institutions, sometimes referred to as the Fourth Estate. Data collected in this study included a pre-survey, a written reflection and post interviews with 4 students as well as artifacts such as social media posts. Students employed two main strategies to draw attention to civic issues on social media: audience-signaling and networking. Further, students learned to seek credible and diverse information using class accounts on TikTok, Instagram, and Twitter. Finally, students offered definitions of digital citizenship and shared thoughts about how schools should teach it via social media. This study fills a gap in the research literature about K-12 teaching with social media; few prior studies take advantage of social media’s affordance as a bridge between the classroom and communities outside the school. This study also illuminates learning as schools globally moved online in response to the pandemic.
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Title: SOCIAL DETERMINANTS OF BREASTFEEDING : THE ROLE OF PRENATAL FOOD INSECURITY
Creator: Robinson, Chelsea
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Background: Relatively little work has quantified associations between prenatal food insecurity and breastfeeding practices; however, understanding the implications of prenatal food insecurity may support food insecurity screening recommendations during prenatal care. Therefore, the purpose of this study was to investigate associations between prenatal food insecurity and breastfeeding initiation and duration until 3 months postpartum. Method: This study utilized data from a prospective...
Show moreBackground: Relatively little work has quantified associations between prenatal food insecurity and breastfeeding practices; however, understanding the implications of prenatal food insecurity may support food insecurity screening recommendations during prenatal care. Therefore, the purpose of this study was to investigate associations between prenatal food insecurity and breastfeeding initiation and duration until 3 months postpartum. Method: This study utilized data from a prospective Michigan pregnancy cohort. Women were recruited during their first prenatal visit with planned follow-up through early childhood. Prenatal food insecurity was assessed during pregnancy, and breastfeeding initiation and duration were assessed at the 3-month postpartum visit. Multiple logistic regression models were used to evaluate associations between prenatal food insecurity and the two primary outcomes: breastfeeding initiation and breastfeeding status at 3-months postpartum. Cox proportional hazard ratios were used to assess differences in the risk of breastfeeding cessation until 3 months postpartum by food insecurity status. An adversity index was created to stratify women into higher- and lower-risk groups for not breastfeeding. Associations between food insecurity and breastfeeding at 3 months postpartum (yes/no) were assessed via Fisher’s Exact test within each group. Results: In the unadjusted models, women who reported food insecurity during pregnancy were less likely to initiate breastfeeding (OR = 0.39; 95% CI: 0.21-0.69) and continue breastfeeding until 3 months postpartum (OR = 0.35; 95% CI: 0.20-0.61) compared to food secure women, but the associations were no longer significant after adjustment for sociodemographic and health-related factors. Prenatal food insecurity was not associated with breastfeeding at 3 months postpartum in analyses stratified into high- and low-adversity groups. Conclusions: Prenatal food insecurity is a strong predictor of breastfeeding practices. Though not significantly associated with breastfeeding practices after adjustment, screening for prenatal food insecurity may help clinicians identify women who may need more supports to initiate and maintain breastfeeding.
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Title: MENTAL HEALTH AND THE URBAN ENVIRONMENT : A BIBLIOMETRIC MAPPING OF KNOWLEDGE STRUCTURE AND TRENDS
Creator: Van Winkle, Taylor
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The literature on the urban environment, health, and well-being has steadily increased over the last decade. This paper aims to offer a better understanding of the state of the literature on assessing the urban environment and health through mapping the field of research through a scoping review and illuminating emerging trends and future research using keyword frequency and bibliometric analysis. Uniquely, this study drew 495 articles from four distinct journal databases (PubMed, Scopus, Web...
Show moreThe literature on the urban environment, health, and well-being has steadily increased over the last decade. This paper aims to offer a better understanding of the state of the literature on assessing the urban environment and health through mapping the field of research through a scoping review and illuminating emerging trends and future research using keyword frequency and bibliometric analysis. Uniquely, this study drew 495 articles from four distinct journal databases (PubMed, Scopus, Web of Science, and ProQuest), whereas traditional bibliometric analyses draw from a single source. By drawing from a broader base of knowledge, this study offers a more holistic view of the trends in the field of research on the connection between urban environments and well-being to better identify future research pathways. The results show trends of a consistent increase in research on the topic over the last decade. Research published on this topic is fragmented, with consistent but isolated focus on physical health, mental health, and environmental characteristics. Overall, in this field, physical health is most often assessed in relationship to the urban built environment, while mental health is most often assessed in connection to the urban natural environment. This paper also provides information on influential authors in this field of research. This study concludes by highlighting gaps and making recommendations for future research in the field. Prominent gaps are related to using interdisciplinary and scalable approaches to understanding the relationship between urban environments and overall well-being.
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Title: TEMPORAL LINKAGES BETWEEN NEARSHORE BATHYMETRY, SHORE ICE MORPHOLOGY, AND GEOMORPHIC CHANGE ALONG A COLD-CLIMATE COASTLINE
Creator: Hartley, Brittany M.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The nearshore ice complex (NIC) though previously studied, has given researchers muddled conclusions when studies are compared, as the documented morphological response to ice presence has been varied. This blurriness of understanding promoted the opportunity for research, and with the availability of new and improved technology, an opportunity for high accuracy analysis also arises. This study showed that ice ridge location corresponded to the bar and trough system in lakebed morphology,...
Show moreThe nearshore ice complex (NIC) though previously studied, has given researchers muddled conclusions when studies are compared, as the documented morphological response to ice presence has been varied. This blurriness of understanding promoted the opportunity for research, and with the availability of new and improved technology, an opportunity for high accuracy analysis also arises. This study showed that ice ridge location corresponded to the bar and trough system in lakebed morphology, rather than just a nearshore bar or trough. Along with that, the ice presence lowered the overall elevation of the lakebed profile, and this promoted erosion throughout the remainder of the study period. During the entirety of the research study period, the most change that was documented was found between August and November 2020 due to a large, recoded storm event that moved through the study location.
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Title: THE EFFECTS OF MEDIUM AND LARGE-SCALE FARMS ON YOUNG PEOPLE’S EMPLOYMENT IN AGRICULTURE : EVIDENCE FROM TANZANIA
Creator: Samboko, Paul C.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: There is limited empirical evidence on how the growth of large- and medium-scale farms is affecting employment outcomes across the whole agricultural sector in developing countries, and especially among young people (age 15-35 years). A priori, it is impossible to determine how medium- and large-scale farms affect employment for young people in agriculture. Using employment data for young people in Tanzania, this study examines whether increases in the region-level share of cropping...
Show moreThere is limited empirical evidence on how the growth of large- and medium-scale farms is affecting employment outcomes across the whole agricultural sector in developing countries, and especially among young people (age 15-35 years). A priori, it is impossible to determine how medium- and large-scale farms affect employment for young people in agriculture. Using employment data for young people in Tanzania, this study examines whether increases in the region-level share of cropping households that are medium- and large-scale farms (MLSFs) improve or worsen agricultural employment outcomes for young people. The outcomes include: (i) employment in crop/livestock production on own farm; (ii) self-employment in agribusiness activities and (iv) employment in agriculture via any of the first three categories above.Correlated random effects probit model results suggest that the growth of medium-scale farms is associated with reductions in the participation of young people in the production of crops/livestock on their own or their family’s farms. It is also associated with a reduction in the employment of young people in the agricultural sector overall. The growth of large-scale farms is associated with an increase in self-employment in agriculture by young people. The government needs to be cognizant of the effects of different farm sizes on employment. Medium-scale farms may not be an avenue to improve young people’s involvement in agriculture. However, large-scale farm expansion may improve young adult’s employment in agricultural employment
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Title: Examining an Important Assumption in the Faultline Literature
Creator: Guo, Zhiya
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Group faultlines are defined as hypothetical dividing lines that split a team into subgroups based on the alignment of team members’ attributes. Prior faultline research has almost exclusively focused on the implications of between-subgroup relationships assuming that “team members form homophilous ties on either side of a faultline by associating with others in the team who have similar demographic attributes” (Ren et al., 2015, p. 390). However, this important assumption has not been tested...
Show moreGroup faultlines are defined as hypothetical dividing lines that split a team into subgroups based on the alignment of team members’ attributes. Prior faultline research has almost exclusively focused on the implications of between-subgroup relationships assuming that “team members form homophilous ties on either side of a faultline by associating with others in the team who have similar demographic attributes” (Ren et al., 2015, p. 390). However, this important assumption has not been tested. Drawing from social comparison theory and its “similarity hypothesis,” I argue that homogeneous, faultline-based subgroups may serve as a hotbed for social comparisons, and comparisons on social power can engender conflict under certain circumstances, triggering within-subgroup conflict. More specifically, consistent with the emerging research that recognizes different types of group faultlines, I outlined a) different dimensions that different faultline-based subgroups are more likely to compare and b) the downstream effects of these comparisons. Hypotheses were tested using multi-wave, round-robin data from multiple intact work teams of full-time employees. Results largely supported my predictions regarding knowledge-based subgroups but not so much for identity-based subgroups or resource-based subgroups. Implications and future directions are discussed.
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Title: PALETTEVIZ : A METHOD FOR VISUALIZATION OF HIGH-DIMENSIONAL PARETO-OPTIMAL FRONT AND ITS APPLICATIONS TO MULTI-CRITERIA DECISION MAKING AND ANALYSIS
Creator: Talukder, AKM Khaled Ahsan
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Visual representation of a many-objective Pareto-optimal front in four or more dimensional objective space requires a large number of data points. Moreover, choosing a single point from a large set even with certain preference information is problematic, as it imposes a large cognitive burden on the decision-makers. Therefore, many-objective optimization and decision-making practitioners have been interested in effective visualization methods to en- able them to filter down a large set to a...
Show moreVisual representation of a many-objective Pareto-optimal front in four or more dimensional objective space requires a large number of data points. Moreover, choosing a single point from a large set even with certain preference information is problematic, as it imposes a large cognitive burden on the decision-makers. Therefore, many-objective optimization and decision-making practitioners have been interested in effective visualization methods to en- able them to filter down a large set to a few critical points for further analysis. Most existing visualization methods are borrowed from other data analytics domains and they are too generic to be effective for many-criterion decision making. In this dissertation, we propose a visualization method, using star-coordinate and radial visualization plots, for effectively visualizing many-objective trade-off solutions. The proposed method respects some basic topological, geometric and functional decision-making properties of high-dimensional trade- off points mapped to a three-dimensional space. We call this method Palette Visualization (PaletteViz). We demonstrate the use of PaletteViz on a number of large-dimensional multi- objective optimization test problems and three real-world multi-objective problems, where one of them has 10 objective and 16 constraint functions. We also show the uses of NIMBUS and Pareto-Race concepts from canonical multi-criterion decision making and analysis literature and introduce them into PaletteViz to demonstrate the ease and advantage of the proposed method.
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Title: Dynamical Systems Analysis Using Topological Signal Processing
Creator: Myers, Audun
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Topological Signal Processing (TSP) is the study of time series data through the lens of Topological Data Analysis (TDA)—a process of analyzing data through its shape. This work focuses on developing novel TSP tools for the analysis of dynamical systems. A dynamical system is a term used to broadly refer to a system whose state changes in time. These systems are formally assumed to be a continuum of states whose values are real numbers. However, real-life measurements of these systems only...
Show moreTopological Signal Processing (TSP) is the study of time series data through the lens of Topological Data Analysis (TDA)—a process of analyzing data through its shape. This work focuses on developing novel TSP tools for the analysis of dynamical systems. A dynamical system is a term used to broadly refer to a system whose state changes in time. These systems are formally assumed to be a continuum of states whose values are real numbers. However, real-life measurements of these systems only provide finite information from which the underlying dynamics must be gleaned. This necessitates making conclusions on the continuous structure of a dynamical system using noisy finite samples or time series. The interest often lies in capturing qualitative changes in the system’s behavior known as a bifurcation through changes in the shape of the state space as one or more of the system parameters vary. Current literature on time series analysis aims to study this structure by searching for a lower-dimensional representation; however, the need for user-defined inputs, the sensitivity of these inputs to noise, and the expensive computational effort limit the usability of available knowledge especially for in-situ signal processing.This research aims to use and develop TSP tools to extract useful information about the underlying dynamical system's structure. The first research direction investigates the use of sublevel set persistence—a form of persistent homology from TDA—for signal processing with applications including parameter estimation of a damped oscillator and signal complexity measures to detect bifurcations. The second research direction applies TDA to complex networks to investigate how the topology of such complex networks corresponds to the state space structure. We show how TSP applied to complex networks can be used to detect changes in signal complexity including chaotic compared to periodic dynamics in a noise-contaminated signal. The last research direction focuses on the topological analysis of dynamical networks. A dynamical network is a graph whose vertices and edges have state values driven by a highly interconnected dynamical system. We show how zigzag persistence—a modification of persistent homology—can be used to understand the changing structure of such dynamical networks.
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Title: The Impact of Multiple Forms of Discrimination on Mental Health in Transgender and Gender Diverse People
Creator: Glozier, Kalei
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Transgender and gender diverse (TGD) people experience a variety of stressors, one of which being discrimination. These experiences of discrimination are embedded within power structures that privilege cisgender, white, heterosexual individuals, and those with other dominant identities and result in the marginalization of those outside of those identities across a multitude of contexts. This study examines experiences of discrimination in a sample of 158 TGD individuals and the relationship...
Show moreTransgender and gender diverse (TGD) people experience a variety of stressors, one of which being discrimination. These experiences of discrimination are embedded within power structures that privilege cisgender, white, heterosexual individuals, and those with other dominant identities and result in the marginalization of those outside of those identities across a multitude of contexts. This study examines experiences of discrimination in a sample of 158 TGD individuals and the relationship between discrimination, mental health, and social disadvantage. The current study used latent class analysis (LCA) to separate participants into classes based on their experiences of discrimination based on their identities: Class 1 (All Types)- had the highest probability of endorsing all types of discrimination experiences, Class 2 (Few Types)- had a low probability of endorsing discrimination experiences based on their identity, and Class 3 (SGM Types)- had a high probability of endorsing discrimination experiences related to gender identity, gender presentation, and sexuality, but a low probability of endorsing discrimination based on race and ancestry. Class membership did not significantly predict mental health outcomes; however, social disadvantage was a predictor of mental health outcomes. Thus, social disadvantage should be systematically addressed to prevent poor mental health outcomes in TGD populations.
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Title: ASSESSING DISASTER MANAGEMENT EFFECTS ON RECOVERY OUTCOMES IN RURAL POST-DISASTER JAPAN
Creator: Ward, Kayleigh
Date: 2022
Collection: Electronic Theses & Dissertations
Description: As a country frequented by natural disasters, Japan has robust disaster management systems that can be employed quickly to mitigate human, environmental, and economic harm and losses. However, these systems tend to be most effective when handling small-scale localized disasters. In the face of the 2011 Great East Japan Earthquake which decimated the northeastern communities of the Tohoku region, Japan’s disaster management system collapsed, unable to handle such large scale and widespread...
Show moreAs a country frequented by natural disasters, Japan has robust disaster management systems that can be employed quickly to mitigate human, environmental, and economic harm and losses. However, these systems tend to be most effective when handling small-scale localized disasters. In the face of the 2011 Great East Japan Earthquake which decimated the northeastern communities of the Tohoku region, Japan’s disaster management system collapsed, unable to handle such large scale and widespread damage. In the ten years since the disaster many rural communities have contended with a variety of social and economic problems, often left unremedied despite on-going government intervention. In this context, this dissertation will explore the complex problems in Minamisanriku, Miyagi—a rural coastal community decimated by the 2011 Great East Japan Earthquake. By engaging and collaborating with organizations in this community, I assess the connections between disaster management and post-disaster recovery outcomes through various applications of social capital and power. I first investigate how historical legacies of national government policies influenced recovery outcomes in the Tohoku region and how have these processes influenced economic restructuring and social development in Minamisanriku during reconstruction. Next, I consider how governance structures within Miyagi prefecture influenced the social and economic development of Minamisanriku during reconstruction. Lastly, I look to how disaster management affects the ability of residents to handle locally-identified and in turn, how residents utilize their social capital to driver social and economic recovery. I assess several key ideas on the connections between forms and theories of social capital and how they affect long-term disaster recovery outcomes through the disaster management process. The dissertation is situated to improve our understanding of how social capital affects rural communities’ ability to respond to these troubles and to craft context specific solutions to them. It also offers a variety of policy recommendations about how to improve community-centered recovery within disaster management frameworks.
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Title: SYNTHETIC BIOLOGY APPROACHES ESTABLISH THE FOUNDATION FOR SUSTAINABLE PRODUCTION OF HIGH VALUE TERPENOIDS
Creator: Bibik, Jacob David
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Plants have become a promising platform for sustainable bioproduction of an array of natural products and specialty chemicals. Of particular interest are terpenes and the functionalized terpenoids, which represent the largest and most diverse class of natural products. These natural products are commonly used commercially as major constituents of flavorings and fragrances, oils, pigments, and pharmaceuticals, while having many other applications. Given the diversity and structural complexity...
Show morePlants have become a promising platform for sustainable bioproduction of an array of natural products and specialty chemicals. Of particular interest are terpenes and the functionalized terpenoids, which represent the largest and most diverse class of natural products. These natural products are commonly used commercially as major constituents of flavorings and fragrances, oils, pigments, and pharmaceuticals, while having many other applications. Given the diversity and structural complexity of many terpenoids, they are often expensive and difficult, if not impossible, to chemically synthesize. Engineering these biosynthetic pathways in plant hosts may provide a sustainable platform to access terpenoids for industrial production. While plants offer a sustainable production platform, metabolic engineering for chemical production has largely focused on microbial hosts, and further development of strategies and tools for plant engineering is needed. In my dissertation, I have taken multi-pronged approaches to further develop sustainable bioproduction of terpenoids in plants. First, I developed strategies to optimize, re-target, and compartmentalize production of squalene, a C30 triterpene, within plant cells to improve yields in plants. Re-targeting the final steps in squalene production, farnesyl diphosphate synthase (FDPS) and squalene synthase (SQS), from the cytosol to plastids enabled compartmentalization of biosynthesis away from competing cytosolic enzymes. I then anchored an optimized FDPS and SQS pair to the surface of cytosolic lipid droplets through fusions to the Nannochloropsis oceanica Lipid Droplet Surface Protein (NoLDSP), where squalene can be sequestered and stored. Scaffolding the pathway to the surface of lipid droplets increased yields to more than twice that of plastidial targeting. Re-targeting this lipid droplet scaffolding to plastids, produced similar squalene yields as the soluble, plastid targeted pathway, and ameliorated some of the negative effects on photosynthesis. Second, I worked to engineer poplar, a bioenergy crop which emits large amounts of the hemiterpene isoprene, with these pathways as a platform for bioproduction and adding value to a bioenergy pipeline. Transformants were successfully created for plastid targeted squalene production, producing up to 0.63mg/gFW of squalene. The lipid droplet scaffolding strategies appeared toxic during tissue regeneration, suggesting a need for tissue specific engineering of these pathways in future iterations. Third, I developed a pipeline to identify, characterize, and engineer bidirectional promoters (BDPs), which enable divergent expression of two genes and improve gene stacking in plant constructs. As seen above with poplar, plant engineering is often limited by construct size, diverse promoter availability, and expression regulation, and a BDP library enables a range of expression in more compact constructs. I identified 34 BDPs from Populus trichocarpa and Arabidopsis thaliana, characterized their activity via Nicotiana benthamiana transient expression, and engineered select BDPs to further alter activities. Combining these BDPs with previously developed terminator sequences provided further regulation of expression. These genetic tools provide an array of expression activities and enable greater gene stacking options while offering the potential for more fine tuning of expression for multiple genes in a metabolic pathway. The work performed in this dissertation provide strategies to improve production of terpenoids in plants, establish production hosts, and engineer larger, complex pathways.
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Title: UNDERSTANDING DRIVERS OF PLANT MICROBIOME IN MICHIGAN AGRICULTURE : STUDIES OF THE APPLE ROOT ZONE AND COMMON BEAN SEEDS
Creator: Bintarti, Ari Fina
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Plant-associated microbial communities are crucial for plant health and fitness, and may enhance plant tolerance to various environmental stresses. As global climate change threatens crop production and increases demands on sustainable agriculture, harnessing the plant microbiome has become one potential strategy to address these issues. Thus, it is fundamental to understand the relative contributions of both the host plant as well as the environment in shaping the plant microbiome. Moreover,...
Show morePlant-associated microbial communities are crucial for plant health and fitness, and may enhance plant tolerance to various environmental stresses. As global climate change threatens crop production and increases demands on sustainable agriculture, harnessing the plant microbiome has become one potential strategy to address these issues. Thus, it is fundamental to understand the relative contributions of both the host plant as well as the environment in shaping the plant microbiome. Moreover, the response of plant microbiomes to stress and any consequences of microbiome stress responses for the host plants are poorly understood, though this information is critical to achieve a basis of knowledge for plant microbiome engineering. My research aimed to contribute to this knowledge by investigating the factors that structure root- and seed-associated microbial communities of two valuable crops for Michigan’s agricultural economy: apple and common bean. The first chapter of my dissertation aimed to assess the biogeography of bacterial, archaeal, fungal, and nematode communities in the root zone of apple trees, and to determine their relationships with each other and their changes over natural abiotic gradients across orchards. I also assessed the influence of plant cultivar on microbiome structure in the root zone. I found that root zone microbiome community structure was strongly affected by geographic location and edaphic properties of soil. The next chapter of my dissertation investigated the variability of seed endophyte community of common bean (Phaseolus vulgaris L.). My results showed that plant-to-plant variability under controlled growth conditions exceeded within-plant variability among seeds from different pods. My study developed protocols and added insights to the growing toolkit of approaches to understand the plant-microbiome engagements that support the health of agricultural and environmental ecosystems. The last chapter assessed the responses of common bean seed endophytes to drought stress in the field across two growing locations and four genotypes of common bean. To summarize, this work advances foundational knowledge of the seed microbiome as a critical component of the plant microbiome, and in the context of two key crops for Michigan agriculture.
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Title: Fidelity to the ACT SMART Toolkit : An Assessment of Implementation Strategy Fidelity
Creator: Tschida, Jessica
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Although evidence-based practices (EBPs) have been shown to improve a variety of outcomes for autistic children, they are often inconsistently implemented or not implemented in community settings where many autistic children primarily receive care. One multi-faceted implementation strategy that researchers have developed and tested in a pilot study to support the implementation of EBPs for ASD in community settings is The Autism Community Toolkit: Systems to Measure and Adopt Research-Based...
Show moreAlthough evidence-based practices (EBPs) have been shown to improve a variety of outcomes for autistic children, they are often inconsistently implemented or not implemented in community settings where many autistic children primarily receive care. One multi-faceted implementation strategy that researchers have developed and tested in a pilot study to support the implementation of EBPs for ASD in community settings is The Autism Community Toolkit: Systems to Measure and Adopt Research-Based Treatments (ACT SMART Toolkit). Here, we used a case study approach to assess fidelity to the toolkit during its pilot study (implementation strategy fidelity) using measures of adherence, dose, and participant responsiveness and examined the relationship between implementation strategy fidelity and EBP use in an exploratory analysis. Overall, we found that adherence, dose, and participant responsiveness to the ACT SMART Toolkit were high with some variability by toolkit phase and activity. However, our exploratory analysis was ultimately unequipped to evaluate the relationship between increased fidelity and increased EBP use given the limited sample size of the pilot study. Our case study evaluation provides one of the first models of considering fidelity in the context of multi-faceted implementation strategies as well as important insights into potential core and peripheral components of the ACT SMART Toolkit.
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