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Title: Flexible hierarchical Bayesian modeling extensions to improve whole genome prediction and genome wide association analyses
Creator: Chen, Chunyu (Graduate of Michigan State University)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Whole genome prediction (WGP) has been widely implemented in animal and plant breeding for genomic selection of economically important traits, having already accelerated genetic progress for economically important traits in some species especially dairy cattle. Genome wide association (GWA) analysis is used for screening genomic regions that may include important candidate genes segregating for the trait of interest and is being increasingly integrated with WGP analysis. Both WGP and GWA...
Show more"Whole genome prediction (WGP) has been widely implemented in animal and plant breeding for genomic selection of economically important traits, having already accelerated genetic progress for economically important traits in some species especially dairy cattle. Genome wide association (GWA) analysis is used for screening genomic regions that may include important candidate genes segregating for the trait of interest and is being increasingly integrated with WGP analysis. Both WGP and GWA typically represent m226Bn problems as defined by a large number of single nucleotide polymorphism (SNP) markers (m) and comparably much smaller number of individuals (n). Two broad types of parametric models are typically considered for these analyses: traditional best linear unbiased prediction approaches based on SNP marker effects being normally distributed and Bayesian WGP models that allow more flexible specifications for SNP marker effects based on either heavy-tailed or variable selection specifications. Bayesian WGP models can achieve higher prediction accuracies than traditional approaches in many applications if properly tuned; however, their implementation can be computationally challenging. My dissertation was aimed to address some of these emerging issues in Bayesian WGP models as well as providing software tools for real data applications. In Chapter 2, I developed an expectation maximization (EM) algorithm as a fast alternative to traditional Markov Chain Monte Carlo (MCMC) for Bayesian WGP models. I proposed EM implementations for two models, heavy-tailed BayesA and stochastic search and variable selection (SSVS) adapting the EM algorithm for maximum a posterior (MAP) inference of SNP effects and adapting REML like strategies to estimate key hyperparameters. Using a comprehensive simulation study and real data analysis, I found that these empirical Bayes approaches can be quite sensitive to starting values for SNP effects. However, using a deterministic annealing variant of EM, I obtained hyperparameter estimates and prediction accuracies comparable to their MCMC counterparts. In Chapter 3, I further assessed the possibility using two Bayesian WGP models BayesA and SSVS for GWA studies. I also included a popular GWA analysis (EMMAX) based on the utilization of the linear mixed model. In addition to basing inferences on traditional single SNP tests and fixed genomic window tests, I assessed the merit of tests involving adaptively determined windows based on clustering genome into blocks based on linkage disequilibrium. I found that SSVS and BayesA under MCMC and adaptive window tests led to best receiver operating curve (ROC) properties. In Chapter 4, I extended SSVS to single step SSVS to incorporate phenotypes of non-genotyped individuals and compared its performance with corresponding models ignoring these genotypes for both WGP and GWA. I found single step SSVS to be a promising for WGP and GWA, particularly for genetic architectures characterized by a few genes with large effects. In Chapter 5, I combined much of the developments in Chapter 2 to Chapter 4 and beyond in a unified framework as an open source R package BATools to implement several different Bayesian models for WGP and GWA."--Pages ii-iii.
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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: Balancing convergence and diversity in evolutionary single, multi and many objectives
Creator: Seada, Haitham
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Single objective optimization targets only one solution, that is usually the global optimum. On the other hand, the goal of multiobjective optimization is to represent the whole set of trade-off Pareto-optimal solutions to a problem. For over thirty years, researchers have been developing Evolutionary Multiobjective Optimization (EMO) algorithms for solving multiobjective optimization problems. Unfortunately, each of these algorithms were found to work well on a specific range of objective...
Show more"Single objective optimization targets only one solution, that is usually the global optimum. On the other hand, the goal of multiobjective optimization is to represent the whole set of trade-off Pareto-optimal solutions to a problem. For over thirty years, researchers have been developing Evolutionary Multiobjective Optimization (EMO) algorithms for solving multiobjective optimization problems. Unfortunately, each of these algorithms were found to work well on a specific range of objective dimensionality, i.e. number of objectives. Most researchers overlooked the idea of creating a cross-dimensional algorithm that can adapt its operation from one level of objective dimensionality to the other. One important aspect of creating such algorithm is achieving a careful balance between convergence and diversity. Researchers proposed several techniques aiming at dividing computational resources uniformly between these two goals. However, in many situations, only either of them is difficult to attain. Also for a new problem, it is difficult to tell beforehand if it will be challenging in terms of convergence, diversity or both. In this study, we propose several extensions to a state-of-the-art evolutionary many-objective optimization algorithm - NSGA-III. Our extensions collectively aim at (i) creating a unified optimization algorithm that dynamically adapts itself to single, multi- and many objectives, and (ii) enabling this algorithm to automatically focus on either convergence, diversity or both, according to the problem being considered. Our approach augments the already existing algorithm with a niching-based selection operator. It also utilizes the recently proposed Karush Kuhn Tucker Proximity Measure to identify ill-converged solutions, and finally, uses several combinations of point-to-point single objective local search procedures to remedy these solutions and enhance both convergence and diversity. Our extensions are shown to produce better results than state-of-the-art algorithms over a set of single, multi- and many-objective problems."--Pages ii-iii.
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Title: Modelling and control of a turbocharged diesel engine
Creator: Zeng, Tao, (Graduate of Michigan State University)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The diesel engine is known for its high efficiency, performance, and durability. With stringent fuel economy and emission regulations, diesel engines face increasing challenges. To accommodate emission regulations, fuel economy and performance requirements, modern diesel engines are equipped with the variable geometry turbocharger (VGT) and exhaust gas recirculation (EGR) system. VGT extracts energy from the exhaust gas to drive the compressor to improve transient response, steady-state...
Show moreThe diesel engine is known for its high efficiency, performance, and durability. With stringent fuel economy and emission regulations, diesel engines face increasing challenges. To accommodate emission regulations, fuel economy and performance requirements, modern diesel engines are equipped with the variable geometry turbocharger (VGT) and exhaust gas recirculation (EGR) system. VGT extracts energy from the exhaust gas to drive the compressor to improve transient response, steady-state performance, and fuel efficiency under a wide range of engine flow conditions. Meanwhile, EGR dilutes fresh air with exhaust gas to reduce the formation of mono-nitrogen oxides NO and NO2 (NOx). The VGT and EGR control design is complicated due to the natural coupling between VGT and EGR, and high nonlinearity of diesel engine air-path system. The extra assisted power and regenerative power on the turbocharger shaft further increase the control system complexity. In this dissertation, new approaches for turbocharger system modelling and multivariable control design for the coordinated actuation of the VGT-EGR system are investigated. The control design is further extended to hydraulic regenerative assisted turbocharger system.New modelling approaches for turbocharger system are proposed based on turbomachinery physics. Proposed turbine and compressor models eliminate the interpolation error, and especially, allow smooth extrapolation outside the mapped region. A high fidelity reduced order mean value model of a diesel engine for automotive application is developed based on developed turbocharger model. Further, new models for high-speed hydraulic turbines and centrifugal pumps are developed for hydraulic assisted and regenerative turbochargers.A regenerative hydraulic assisted turbocharger (RHAT) system is investigated in this dissertation. A system level approach based on 1-D simulations is used to understand the assist benefits and design trade-offs. Simulation results show that 3-5% fuel economy improvement for FTP 75 driving cycle, depending on different sub-component sizing. The study also identifies technical challenges for optimal design and control of RHAT systems.A linear controller design approach is proposed in this dissertation for regulating both boost pressure and EGR mass flow rate of the VGT-EGR system. The linear quadratic control with integral action is designed based on the linearized system. Local controllers are scheduled based on engine operational parameter: engine speed and fuel injection quantity. The gain scheduled liner controller is validated against baseline controller based on the nonlinear plant. Results show that designed multi-input and multi-output (MIMO) controller can well manage the trade-offs between boost pressure tracking and EGR mass flow tracking, compared to baseline controller (two single input single output (SISO) controllers). A novel approach is proposed for closed-loop control design with respect to engine performance and engine emission trade-offs. The controller design is further extended to assisted and regenerative turbocharger system with VGT and EGR. The results show that emission reduction, engine performance and fuel economy improvement can be achieved at the same time with external power applied to the turbocharger shaft.
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Title: Biomass production potential, theoretical ethanol yield, environmental sustainability of miscanthus x giganteus and nitrogen fertilizer effect on quantity and quality in five lignocellulosic biomass crops in North-Central US
Creator: Wang, Sichao
Date: 2017
Collection: Electronic Theses & Dissertations
Description: ABSTRACTBIOMASS PRODUCTION POTENTIAL, THEORETICAL ETHANOL YIELD, ENVIRONMENTAL SUSTAINABILITY OF MISCANTHUS x GIGANTEUS AND NITROGEN FERTILIZER EFFECT ON QUANTITY AND QUALITY IN FIVE LIGNOCELLULOSIC BIOMASS CROPS IN NORTH-CENTRAL US BYSichao WangIncreasing concerns on climate change and energy security leads to growing emphasis has been placed on lignocellulosic ethanol industry in the U.S. Among many lignocellulosic feedstock crops, little information about long-term production and quality...
Show moreABSTRACTBIOMASS PRODUCTION POTENTIAL, THEORETICAL ETHANOL YIELD, ENVIRONMENTAL SUSTAINABILITY OF MISCANTHUS x GIGANTEUS AND NITROGEN FERTILIZER EFFECT ON QUANTITY AND QUALITY IN FIVE LIGNOCELLULOSIC BIOMASS CROPS IN NORTH-CENTRAL US BYSichao WangIncreasing concerns on climate change and energy security leads to growing emphasis has been placed on lignocellulosic ethanol industry in the U.S. Among many lignocellulosic feedstock crops, little information about long-term production and quality of giant miscanthus (Miscanthus × giganteus) is available in U.S. This study evaluated yield and quality parameters of giant miscanthus in southwest Michigan (KBS) and southcentral Wisconsin (ARL). An attributional life cycle assessment was also performed on giant miscanthus and switchgrass production phases by using empirical data. Nitrogen responses on yield and quality parameters were examined for five perennial bioenergy cropping systems: 1) switchgrass (Panicum virgatum L.); 2) giant miscanthus (Miscanthus × giganteus); 3) a native grass mixture (5 species); 4) an early successional field; and, 5) a restored prairie (18 species). The highest yield of miscanthus reached 22.81 ± 1.023 Mg ha-1 at KBS and 15.7 ± 0.898 Mg ha-1 at ARL. Giant miscanthus exhibited a positive yield response to nitrogen fertilization at both KBS and ARL and had the highest nitrogen fertilizer use efficiency among five cropping systems evaluated in this study. Compared to switchgrass cropping system, the giant miscanthus cropping system is more favorable in GHG emissions reduction when taking gasoline displacement credits into account. Due to higher yield, giant miscanthus had higher energy return on investment than switchgrass at both KBS and ARL.
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Title: Hardware algorithms for high-speed packet processing
Creator: Norige, Eric
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The networking industry is facing enormous challenges of scaling devices to support theexponential growth of internet traffic as well as increasing number of features being implemented inside the network. Algorithmic hardware improvements to networking componentshave largely been neglected due to the ease of leveraging increased clock frequency and compute power and the risks of implementing complex hardware designs. As clock frequencyslows its growth, algorithmic solutions become important...
Show moreThe networking industry is facing enormous challenges of scaling devices to support theexponential growth of internet traffic as well as increasing number of features being implemented inside the network. Algorithmic hardware improvements to networking componentshave largely been neglected due to the ease of leveraging increased clock frequency and compute power and the risks of implementing complex hardware designs. As clock frequencyslows its growth, algorithmic solutions become important to fill the gap between currentgeneration capability and next generation requirements. This paper presents algorithmicsolutions to networking problems in three domains: Deep Packet Inspection(DPI), firewall(and other) ruleset compression and non-cryptographic hashing. The improvements in DPIare two-pronged: first in the area of application-level protocol field extraction, which allowssecurity devices to precisely identify packet fields for targeted validity checks. By usingcounting automata, we achieve precise parsing of non-regular protocols with small, constantper-flow memory requirements, extracting at rates of up to 30gbps on real traffic in softwarewhile using only 112 bytes of state per flow. The second DPI improvement is on the longstanding regular expression matching problem, where we complete the HFA solution to theDFA state explosion problem with efficient construction algorithms and optimized memorylayout for hardware or software implementation. These methods construct automata toocomplex to be constructed by previous methods in seconds, while being capable of 29gbpsthroughput with an ASIC implementation. Firewall ruleset compression enables more firewall entries to be stored in a fixed capacity pattern matching engine, and can also be usedto reorganize a firewall specification for higher performance software matching. A novelrecursive structure called TUF is given to unify the best known solutions to this problemand suggest future avenues of attack. These algorithms, with little tuning, achieve a 13.7%improvement in compression on large, real-life classifiers, and can achieve the same results asexisting algorithms while running 20 times faster. Finally, non-cryptographic hash functionscan be used for anything from hash tables to track network flows to packet sampling fortraffic characterization. We give a novel approach to generating hardware hash functionsin between the extremes of expensive cryptographic hash functions and low quality linearhash functions. To evaluate these mid-range hash functions properly, we develop new evaluation methods to better distinguish non-cryptographic hash function quality. The hashfunctions described in this paper achieve low-latency, wide hashing with good avalanche anduniversality properties at a much lower cost than existing solutions.
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Title: Cardiovascular system modeling : arterial growth and remodeling
Creator: Tilahun, Hailu Getachew
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Vascular systems in the human blood circulation regulate their environment when there are alterations of hemodynamic loading from homeostatic levels, depending on the magnitude and the duration of the changes. The main focus of this work is to develop a bio-chemo-mechanical model of arterial growth and remodeling wherein changes in blood pressure and flow are sustained over weeks or months. Using a two-step kinetic reaction model of collagen, which is the dominant structural protein in...
Show more"Vascular systems in the human blood circulation regulate their environment when there are alterations of hemodynamic loading from homeostatic levels, depending on the magnitude and the duration of the changes. The main focus of this work is to develop a bio-chemo-mechanical model of arterial growth and remodeling wherein changes in blood pressure and flow are sustained over weeks or months. Using a two-step kinetic reaction model of collagen, which is the dominant structural protein in arteries, as a function of arterial wall stress changes, we track and evaluate the temporal change in mass deposition and degradation of extracellular matrix. We employ a constrained mixture model to capture the response of the artery to hemodynamic loadings, leading to strain energy changes that depend on the stiffness and relative mass ratio of the constituents of the artery. In so doing, we investigate the temporal changes of the geometry of the artery over weeks and months. We also explore the possible ranges of the collagen turnover rates, the coupling between collagen turnover and stresses, and the length of time it takes for the vascular stresses to return back to the steady homeostatic states while the artery is still under sustained loadings. The developed mathematical models are verified by previously published mathematical models and validated by comparing the mathematical result with animal experiments. Using reported experimental data, we inversely compute the arterial constituent mass turnover. After minimizing the total error between the simulated and experimental arterial thickness values, parameters such as collagen and smooth muscles degradation rates are estimated. The efficiency of computation is improved by singular value decomposition and regularization. We also study a lumped whole body model in the cardiovascular system with baroreflex. In this model, we incorporate the effect of arteriovenous fistula and can get verifiable results as per reported vascular maturation data."--Pages ii-iii.
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Title: Numeracy, severity, and communicating risk : perceptions of prescription pain medication side effects
Creator: Cox, Jeffrey G. (Jeffrey George)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This dissertation reports on a study that explored how individuals interpret and quantify verbal descriptions of the risk of side effects from a hypothetical prescription pain medication, as well as what factors affect these interpretations. While the European Union has set out recommendations for how these terms quantifiers (e.g., "very rare," "common") should be interpreted, studies (Cox, 2016; Berry, Knapp, & Raynor, 2002; Knapp, Raynor, & Berry, 2004) indicate that individuals...
Show moreThis dissertation reports on a study that explored how individuals interpret and quantify verbal descriptions of the risk of side effects from a hypothetical prescription pain medication, as well as what factors affect these interpretations. While the European Union has set out recommendations for how these terms quantifiers (e.g., "very rare," "common") should be interpreted, studies (Cox, 2016; Berry, Knapp, & Raynor, 2002; Knapp, Raynor, & Berry, 2004) indicate that individuals dramatically overestimate these effects' likelihood. Situated within fuzzy trace theory (Reyna & Brainerd, 1995) the present study assessed how individuals quantify these terms, as well as what internal (e.g., numeracy, existing perceptions of prescription pain medications) and external (e.g., verbal quantifiers used, severity of side effect) factors influence their gist and verbatim processing of risk information. The study used a between-subjects experimental design: 2 ("common"/"rare") X 2 (adverb/no adverb) X 2 (severity) embedded within an online survey about impressions of prescription pain medications. Findings reveal that individuals' existing, general perceptions of prescription pain medications have a larger impact on their gist perceptions than their verbatim ones, while their estimates are significantly higher than experts' recommendations. Important differences between the subjective and objective numeracy scales are also found for participants' confidence in their numerical estimates. Other findings related to the study of risk perceptions, as well as implications for practice and policy, are discussed.
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Title: Information, knowledge, and demand for substitute health inputs : experimental evidence of pesticide use in Zambia
Creator: Goeb, Joseph Christopher
Date: 2017
Collection: Electronic Theses & Dissertations
Description: ABSTRACTINFORMATION, KNOWLEDGE, AND DEMAND FOR SUBSTITUTE HEALTH INPUTS: EXPERIMENTAL EVIDENCE OF PESTICIDE USE IN ZAMBIAByJoseph Christopher GoebMany goods carry health risks that have important impacts on demand and behavior. However, the risks are rarely transparent and, as a result, consumers often have incomplete knowledge of the health risks associated with many of their consumption decisions. This can lead to inefficient behavior. With that in mind, economists have studied the impacts...
Show moreABSTRACTINFORMATION, KNOWLEDGE, AND DEMAND FOR SUBSTITUTE HEALTH INPUTS: EXPERIMENTAL EVIDENCE OF PESTICIDE USE IN ZAMBIAByJoseph Christopher GoebMany goods carry health risks that have important impacts on demand and behavior. However, the risks are rarely transparent and, as a result, consumers often have incomplete knowledge of the health risks associated with many of their consumption decisions. This can lead to inefficient behavior. With that in mind, economists have studied the impacts of risk information on consumer behavior, though the effects are rarely straightforward as there may be risk compensation and substitution effects across inputs and behaviors. This dissertation tests the effects of information on knowledge and demand for two substitute health inputs using a randomized control trial of pesticide users in rural Zambia.Essay 1 contributes to the broader literature on information, knowledge, and preventative health demands, and to the pesticide safety literature by presenting the first randomly controlled test of the impacts of pesticide safety information on willingness-to-pay (WTP) for personal protective equipment (PPE) measured using two Becker-DeGroot-Marschak mechanisms. Despite knowledge improvements from the training, overall effects on demand for PPE were insignificant. We also find that demand for both gloves and masks is highly elastic near their market prices.Essay 2 shows that information significantly changed pesticide choices, which were assessed using stated choice experiments and actual purchase decisions before and after the information intervention. We find that farmers held an erroneous positive price-quality perception for pesticides prior to receiving information, and that information effectively broke that perception. Importantly for health, farmers chose less toxic pesticides more often after receiving information on relative toxicities and health risks. Essay 3 presents a detailed assessment of farmer pesticide knowledge using 22 questions covering pesticide control properties and health risks. We find that Zambian tomato farmers generally know pesticides are harmful to their health, but they lack product-specific knowledge on pesticide toxicity and pesticide control properties. The training program caused an increase in overall pesticide knowledge with large increases in toxicity knowledge, pest control knowledge, and pesticide efficacy knowledge. The effects of information on protective equipment knowledge were insignificant.
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Title: Self-directed learning through the eyes of a Buddhist meditator : (non)control, (non)becoming, and (non)judgement
Creator: Nguyen, Cuong Huy
Date: 2017
Collection: Electronic Theses & Dissertations
Description: By using the meditative inquiry approach, I compare and contrast the philosophy underlying Buddhist meditation, based on my personal experiences with and scholarship on the mindfulness practice, with self-directed learning within the tradition of progressive education, based on the case study of the Jefferson County Open School, a progressive school in Lakewood (CO, USA). I found that Buddhist meditation and self-directed learning have a lot in common. In particular, they both emphasize (non...
Show moreBy using the meditative inquiry approach, I compare and contrast the philosophy underlying Buddhist meditation, based on my personal experiences with and scholarship on the mindfulness practice, with self-directed learning within the tradition of progressive education, based on the case study of the Jefferson County Open School, a progressive school in Lakewood (CO, USA). I found that Buddhist meditation and self-directed learning have a lot in common. In particular, they both emphasize (non)control, (non)becoming, and (non)judgement. As a meditative inquiry, this study has brought about a lot of profound inner transformation in terms of both spirituality and philosophy of education, which are explicitly presented in this dissertation.
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Title: Surface energy characterization and competitive surface equilibria using contact angle
Creator: Stubbs, Barrack Perez
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Surface energy measurements are usually difficult to assess when not considering a solid-air or liquid-air interface. Contact angles was used as a method of obtaining the interfacial energy of a silanol-water surface using carbon tetrachloride as a probing liquid. The theory for this work operated under the assumption that the pKa of a silanol surface could be measured by obtaining a titration like curve as a function of pH. A decrease in contact angle of about 7° was observed at a pH (pKa)...
Show moreSurface energy measurements are usually difficult to assess when not considering a solid-air or liquid-air interface. Contact angles was used as a method of obtaining the interfacial energy of a silanol-water surface using carbon tetrachloride as a probing liquid. The theory for this work operated under the assumption that the pKa of a silanol surface could be measured by obtaining a titration like curve as a function of pH. A decrease in contact angle of about 7° was observed at a pH (pKa) of 3.5. This corresponds to an energy difference of 2 mN/m. -- Abstract.
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Title: Volumes, determinants, and meridian lengths of hyperbolic links
Creator: Burton, Stephan D., 1987-
Date: 2017
Collection: Electronic Theses & Dissertations
Description: We study relationships between link diagrams and link invariants arising from hyperbolic geometry. The volume density of a hyperbolic link K is defined to be the ratio of the hyperbolic volume of K to the crossing number of K. We show that there are sequences of non-alternating links with volume density approaching v_8, where v_8 is the volume of the regular ideal hyperbolic octahedron. We show that the set of volume densities is dense in [0,v_8]. The determinant density of a link K is 2 pi...
Show moreWe study relationships between link diagrams and link invariants arising from hyperbolic geometry. The volume density of a hyperbolic link K is defined to be the ratio of the hyperbolic volume of K to the crossing number of K. We show that there are sequences of non-alternating links with volume density approaching v_8, where v_8 is the volume of the regular ideal hyperbolic octahedron. We show that the set of volume densities is dense in [0,v_8]. The determinant density of a link K is 2 pi log det(K)/c(K). We prove that the closure of the set of determinant densities contains the set [0, v_8]. We examine the conjecture, due to Champanerkar, Kofman, and Purcell that vol(K) < 2 pi log det (K) for alternating hyperbolic links, where vol(K) = vol(S^3\ K) is the hyperbolic volume and det(K) is the determinant of K. We prove that the conjecture holds for 2-bridge links, alternating 3-braids, and various other infinite families. We show the conjecture holds for highly twisted links and quantify this by showing the conjecture holds when the crossing number of K exceeds some function of the twist number of K.We derive bounds on the length of the meridian and the cusp volumeof hyperbolic knots in terms of the topology of essential surfaces spanned by the knot.We provide an algorithmically checkable criterion that guarantees that the meridian length of a hyperbolic knot is below a given bound.As applications we find knot diagrammatic upper bounds on the meridian length and the cusp volume of hyperbolic adequate knots and we obtain new large families of knots withmeridian lengths bounded above by four. We also discuss applications of our results to Dehn surgery.
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Title: Using cover crops in wheat-corn rotations to provide forage while improving soil
Creator: Gerdes, Sabra Lynn
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The time window after wheat harvest in a wheat (Triticum aestivum L.)- corn (Zea mays L.) rotation could be used to grow cover crops (CC) to provide forage while protecting soil from erosion. Field experiments were initiated in East Lansing, MI to determine the consequences of partial removal of CC biomass on soil improvement and crop yield and quality. Soft red winter wheat ('Hopewell' 03360336and 03360336'Red 03360336Dragon') was planted in October of 2013 and 2014 and harvested in July...
Show more"The time window after wheat harvest in a wheat (Triticum aestivum L.)- corn (Zea mays L.) rotation could be used to grow cover crops (CC) to provide forage while protecting soil from erosion. Field experiments were initiated in East Lansing, MI to determine the consequences of partial removal of CC biomass on soil improvement and crop yield and quality. Soft red winter wheat ('Hopewell' 03360336and 03360336'Red 03360336Dragon') was planted in October of 2013 and 2014 and harvested in July 2014 and 2015. Cover crops included: frost-seeded red clover, and summer-seeded alfalfa, cowpea, sunn hemp, radish, oat/field pea mixture, sudangrass, sorghum x sudangrass, and teffgrass. Half of each CC plot was mechanically harvested eight weeks after planting. Harvested forage dry matter yield was greatest for red clover (4.3 Mg ha-1 ); oat-pea mix (2.5 Mg ha-1 ), sudangrass/sudex (1.8 Mg ha-1 ) and radish (1.2 Mg ha-1 ) (P < 0.01) yielded less. Corn grain yield harvested in October averaged 13.7 Mg ha-1 and did not differ across CC species or forage harvest treatment (P > 0.05). Harvesting forage reduced total N removal (TNR) in subsequent corn for red clover only; harvesting forage did not affect TNR after any other CC (CC x harvest interaction, P < 0.05). In the harvested system, TNR did not differ (P > 0.05) between for any CC, but unharvested RCL (374 kg N ha-1 ) had greater (P < 0.01) TNR than oat-pea mix (338 kg N ha-1 ). There were no differences among treatments for soil permanganate oxidizable carbon POXC (P > 0.05). Harvesting cover crops for forage after winter wheat harvest in Michigan can give harvestable forage and acceptable nutritive value."--Page ii.
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Title: Internationalizing graduate education through education abroad : the pedagogy of short-term, faculty-led, education abroad experiences
Creator: Loebick, Karla
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The purpose of this study was to develop understanding of the perspectives of faculty members as leaders of short-term, faculty-led, education abroad at the graduate level ... " Abstract.

Title: Agency in context : a phenomenological study of Chinese college lLearners' intercultural engagement with expatriate instructors
Creator: Larson, Jay B.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "As China increasingly internationalizes its higher education system, growing numbers of Chinese learners and expatriate instructors meet in the classroom, engaging one another from their disparate cultural and pedagogical standpoints. Despite its widespread occurrence, the phenomenon of Chinese learners and Western instructors engaging one another in pedagogically and culturally Chinese institutions is largely neglected in research. Scholarly literature on Chinese learners is dominated by...
Show more"As China increasingly internationalizes its higher education system, growing numbers of Chinese learners and expatriate instructors meet in the classroom, engaging one another from their disparate cultural and pedagogical standpoints. Despite its widespread occurrence, the phenomenon of Chinese learners and Western instructors engaging one another in pedagogically and culturally Chinese institutions is largely neglected in research. Scholarly literature on Chinese learners is dominated by studies of their experiences as international students on Western campuses. In Chinese environments, authors most often examine perspectives of expatriate instructors on their cultural adjustments. The voice of the Chinese learner in China is rarely heard in research. In this study, I turned a phenomenological lens toward 17 Chinese learners' lived experiences of intercultural classroom engagement at China's Southwest University. Drawing on works of Hall (1997a, 1997b), Said (1978), and Simmel (1971), I devised a Progression Model of Intercultural Engagement to frame participants' evolving perceptions of expatriate instructors as culturally foreign Others. I focused my analysis of learners' perceptions through three overlapping areas of inquiry: (a) learners' sense-making processes and management of intercultural teaching and learning; (b) their perceptions of the expatriate instructor as a physical, social, and cultural presence; and, (c) perceptions of expatriate instructor's course design and teaching. I collected data over a two-month period at Southwest University through methods including classroom observations, Chinese language participant essays, and English language interviews. Findings revealed learners exercised ownership and agency in interpreting and managing intercultural engagement with their instructors. Participants expressed ownership of a perceived physically, linguistically, and academically Chinese environment. Within that environment, they initially characterized expatriate instructor by foreign-ness. Learners made further sense of intercultural experience by situating their instructors' foreign-ness in constructed social, pedagogical, linguistic, and cultural roles. These roles assigned purpose to the expatriate instructor's foreign presence, and framed the meanings learners constructed from intercultural engagement. Finally, participants interpreted their relationships with written and spoken English through engagement with expatriate instructors perceived as social, pedagogical, and cultural embodiments of language. In sum, findings indicate perceived cultural context of the environment, and senses of ownership and agency learners exercised in this environment. These findings contribute to the academic dialogue on intercultural teaching and learning, not only in Chinese institutional contexts, but anywhere knowledge construction must bridge cultural assumptions, epistemologies, and pedagogies. This study can inform further inquiry into international learners on Western campuses, multinational classes in education hubs, and Western learners studying abroad. I address these applications, and others, as I conclude this dissertation with recommendations for practice, and implications for research and theory."--Pages ii-iii.
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Title: Seeking or encountering news on the Web : the role of need for cognition and need to evaluate
Creator: Lee, Heysung
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Previous literature has dealt with news consumption patterns on the web, but not many attempts have done to clarify individual differences by focusing on a role of personality variables. This study suggests that high need for cognition will lead digital news consumers to actively seek out news websites to get political information, whereas low need for cognition will lead them to passively encounter political news on social media. The results of the online survey indicate that need for...
Show morePrevious literature has dealt with news consumption patterns on the web, but not many attempts have done to clarify individual differences by focusing on a role of personality variables. This study suggests that high need for cognition will lead digital news consumers to actively seek out news websites to get political information, whereas low need for cognition will lead them to passively encounter political news on social media. The results of the online survey indicate that need for cognition does not predict news consumption on the web, but only need to evaluate positively correlates to news website usage. Also, both variables positively correlate to active sharing and commenting on political information in social media, attention to political news, and political knowledge. -- Abstract.
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Title: Evaluating the conservation and agricultural applications of orchard nest boxes for a declining raptor
Creator: Shave, Megan Ellen
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Human activities over the past 50 years have caused changes in ecosystems that have led to gains in economic development at the cost of biodiversity loss and degradation of ecosystem services, the functions and processes of ecosystems that benefit human well being. For example, agricultural expansion and intensification has degraded wildlife habitat by removing sources of nesting and roosting cavities, particularly mature trees, which can negatively affect abundance and diversity of animal...
Show moreHuman activities over the past 50 years have caused changes in ecosystems that have led to gains in economic development at the cost of biodiversity loss and degradation of ecosystem services, the functions and processes of ecosystems that benefit human well being. For example, agricultural expansion and intensification has degraded wildlife habitat by removing sources of nesting and roosting cavities, particularly mature trees, which can negatively affect abundance and diversity of animal taxa that provide regulating ecosystem services, such as pest reduction. Many cavity-dependent species will use nest boxes in areas where natural cavities are scarce, thus nest boxes are an easily implemented landscape enhancement. In this dissertation, I drew from theoretical frameworks of population dynamics, foraging ecology, parental care, and predator-prey interactions to assess the potential benefits of nest boxes in terms of conservation of a declining raptor and enhancement of pest reduction services in a fruit-growing region. Although the American Kestrel (Falco sparverius) is the most common falcon in North America, multiple monitoring programs have detected significant and widespread population declines. While the causes of these declines at the continent-wide scale are not yet understood, at the local scale, many breeding kestrel populations are limited by availability of nest sites. In Chapter 1, I monitored 18 new nest boxes installed in cherry orchards (Prunus spp.) in northwestern Michigan and found that kestrels made nesting attempts in 100% of the boxes and showed high reproductive rates. Furthermore, models of daily survival rates for nests and brood size at fledging for successful nests indicated that kestrels were highly tolerant of both traditional monitoring techniques (opening the box) and newer camera technologies (a pole-mounted video camera and nest-box video cameras). In Chapter 2, I used roadside transect surveys and multi-season occupancy modeling to determine that the installation of nest boxes has increased the presence of kestrels in the region between 2013 and 2016. Chapters 1 and 2 indicate that orchard nest boxes can benefit the local conservation of kestrels by increasing breeding populations, which may in turn benefit agriculture by promoting kestrel presence, and therefore predation on pest species, in and around orchards. In Chapter 3, I used nest box video cameras to determine that kestrels provision their nestlings with known orchard pests, including grasshoppers, voles, and frugivorous birds; furthermore, I observed generalizable trends in kestrel prey removal based on nestling age, seasonal timing of prey availability, brood size and sex ratio, weather, and adult female movements relative to the nest box. In Chapter 4, I used transect surveys to determine that fruit-eating bird counts were lower in orchards with active kestrel nest boxes, thus kestrel activity associated with nest boxes likely acts as a reliable cue of predation risk that, in combination with direct consumption, reduces fruit-eating bird abundances in orchards. Finally, in Chapter 5, I used live-trapping to determine that summer small mammal abundances were lower in orchards with active kestrel boxes and orchards that had been more recently mowed; however, these differences did not carry over as differences in winter presence in orchards, when mammal damage to trees is most likely. Based on the results, I recommend that future projects utilize a consistent surveying protocol across seasons, conduct winter surveys in orchards without rodenticide use, and combine small mammal surveys with fruit and tree damage assessments in order to identify which species are responsible for damage throughout the year and under different conditions (e.g., with variation in snowfall).
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Title: Impact of wind generation on grid frequency stability
Creator: Nguyêñ, Nga (Graduate of Michigan State University)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The integration of renewable energy sources into power systems has gathered significant momentum globally because of its unlimited supply and environmental benefits. Within the portfolio of renewable energy, wind power has been experiencing a steadily increasing growth. Despite its well known benefits, wind power poses several challenges in grid integration. The inherent intermittent and non-dispatchable features of wind power not only inject additional fluctuations to the already variable...
Show moreThe integration of renewable energy sources into power systems has gathered significant momentum globally because of its unlimited supply and environmental benefits. Within the portfolio of renewable energy, wind power has been experiencing a steadily increasing growth. Despite its well known benefits, wind power poses several challenges in grid integration. The inherent intermittent and non-dispatchable features of wind power not only inject additional fluctuations to the already variable nature of frequency deviation, they also decrease frequency stability and reliability by reducing the inertia and the regulation capability. To ensure the system security, the integration of wind power must be limited and the wind generation has to operate in the condition that enables wind generator to support the frequency control. As a result, the reliability of wind power must be re-estimated based on the wind power that can be accepted by the system, instead of the total wind production. This research examines the impacts of wind generation on system inertia and theregulation capability as well as the effect on tie-line flows and area control error. The effect of wind power on frequency regulation capability at different penetration levels is also investigated. The mathematical and simulation model to determine maximum wind power penetration level, given a frequency deviation limit, is developed. Based on the proposed mathematical model of wind penetration limit, the negative impact of wind on system reliability is examined. An improved method to coordinate the energy storage with the existing system to improve the wind-integrated system reliability while maintaining the system frequency security is also proposed. An approachto assist the integration of wind power with grid-scale virtual energy storage will be developed and examined. This thesis discusses the pertinent background and state of the art, and describes the proposed approaches and the results obtained.
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Title: The influence of peer feedback on writing achievement and individual writing self-efficacy
Creator: Zellner, Andrea Lynn
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This study examined the influence of peer feedback and review on individual writing achievement and self-efficacy. Undergraduate first-year composition students engaged in normal instructional activities used the Eli Review program in order to conduct peer feedback and review sessions. Using the data collected from surveys and through the web-based peer review system Eli Review, the influence of giving and receiving writing feedback in peer review groups on both individual writing achievement...
Show moreThis study examined the influence of peer feedback and review on individual writing achievement and self-efficacy. Undergraduate first-year composition students engaged in normal instructional activities used the Eli Review program in order to conduct peer feedback and review sessions. Using the data collected from surveys and through the web-based peer review system Eli Review, the influence of giving and receiving writing feedback in peer review groups on both individual writing achievement and individual self-efficacy was modeled using a social-network analysis methodology. The findings showed that students did not improve over the course of the semester in achievement or self-efficacy. Additionally, social network analysis suggested a negative relationship between the quality of feedback received on writing achievement, while no relationship was found between the quality of feedback given on writing achievement and self-efficacy. The findings suggest that practitioners should focus on modeling the feedback cycle, specifically ways to incorporate feedback into the revision process. -- Abstract.
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Title: Local food in perspective : place, time, authenticity, and the relocalization of the food system
Creator: Giorda, Erica
Date: 2017
Collection: Electronic Theses & Dissertations
Description: While the research on local food systems and movements is well established, the time related aspects of local food promotion, production, and consumption have been barely explored.This dissertation starts to address that topic through three articles: a theoretical analysis of time and agency in food relocalization processes, and two case studies that address ideas of authenticity and heritage, community ties, and place making practices based on the selective framing of shared temporalities at...
Show moreWhile the research on local food systems and movements is well established, the time related aspects of local food promotion, production, and consumption have been barely explored.This dissertation starts to address that topic through three articles: a theoretical analysis of time and agency in food relocalization processes, and two case studies that address ideas of authenticity and heritage, community ties, and place making practices based on the selective framing of shared temporalities at Eastern Market in Detroit.First, I use French Convention Theory to examine how a set of vendors at Eastern Market in Detroit sell their food emphasizing craftsmanship and cultural values more than price or provenance. The work of these vendors manifests a form of compromise between the Domestic and Market worlds that is based on reputation and regard. This shifts the meaning of local food from provenance to a form of authenticity based on the presentation of heritage and community ties.Second, I investigate the ways local actors use the physical arrangements of the space inside and around the Market and how the promotion of local food through new and old references to craftsmanship, care and tradition contribute to the creation of a sense of place. Following Gieryn and Molotch et al., place-making is presented as a recursive process led by ‘strategically placed actors’ (Giddens 1984) whose action creates a conceptual narrative that may create exclusionary spaces. I adopt a visual approach to offer a fresh perspective in terms of understanding the intersection of time and space, history and geography, as well as clarifying how ideas of locality and place are performed.Third, I analyze embeddedness as pertinent to local food systems, from the perspective of time. Drawing from ethnographic research and current literature I highlight the different ways in which time is a relevant variable that makes food embedded in social systems and reduces the alienating effects of the commodification of the food chain. Appeals to tradition, history, ancestry, duration, co-presence and time commitment are different time-related aspects that support the embedding of food production, preparation, and consumption. This approach also allows for identifying agency in wider sets of actions and behaviors than looking at spatial patterns only.The three papers together contribute to increasing the understanding and theorization of place making processes, the relevance of seemingly marginal practices with respect to the determination of agency, and to increasing the focus on the temporal gaze in relation to commodification and de-commodification practices in the areas of local food production and consumption.
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