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Pages
 Title
 The magnetic susceptibility of oxygen and nitric oxide at low field strength
 Creator
 Burris, Albert
 Date
 1943
 Collection
 Electronic Theses & Dissertations
 Title
 Modeling municipal expenditures in Michigan
 Creator
 Selim, Jahangir
 Date
 1988
 Collection
 Electronic Theses & Dissertations
 Title
 A comparison of forecasting accuracy of several quantitative forecasting methods : application to lodging sales tax and use tax collections in Michigan
 Creator
 Kim, Jong Ho
 Date
 1994
 Collection
 Electronic Theses & Dissertations
 Title
 Field machinery system modeling and requirements for selected Michigan cash crop production systems
 Creator
 Singh, Devindar
 Date
 1978
 Collection
 Electronic Theses & Dissertations
 Title
 Modeling spatial and temporal variations in tourismrelated employment in Michigan
 Creator
 Chen, SzReng
 Date
 1988
 Collection
 Electronic Theses & Dissertations
 Title
 Testing of regression functions when responses are missing at random
 Creator
 Li, Xiaoyu
 Date
 2012
 Collection
 Electronic Theses & Dissertations
 Description

This thesis consists two chapters. The first chapter proposes a class of minimum distance tests for fitting a parametric regression model to a regression function when some responses are missing at random. These tests are based on a class of minimum integrated square distances between a kernel type estimator of a regression function and the parametric regression function being fitted. The estimators of the regression function are based on two completed data sets constructed by imputation and...
Show moreThis thesis consists two chapters. The first chapter proposes a class of minimum distance tests for fitting a parametric regression model to a regression function when some responses are missing at random. These tests are based on a class of minimum integrated square distances between a kernel type estimator of a regression function and the parametric regression function being fitted. The estimators of the regression function are based on two completed data sets constructed by imputation and inverse probability weighting methods. The corresponding test statistics are shown to have asymptotic normal distributions under null hypothesis. Some simulation results are also presented.The second chapter considers the problem of testing the equality of two nonparametric regression curves against a onesided alternatives based on two samples with possibly distinct design and error densities, when responses are missing at random. This chapter proposes a class of tests using imputation and covariate matching. The asymptotic distributions of these test statistics are shown to be Gaussian under null hypothesis and a class of local nonparametric alternatives. The consistency of these tests against a large class of fixed alternatives is also established. This chapter also includes a simulation study, which assesses the finite sample behavior of a member of this class of tests.
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 Title
 Highorder computerassisted estimates of topological entropy
 Creator
 Grote, Johannes
 Date
 2009
 Collection
 Electronic Theses & Dissertations
 Title
 Modeling of hydrogenbased plasmas in microwave plasmaassisted chemical vapor deposition reactors at moderate pressures
 Creator
 Meierbachtol, Collin Stephen
 Date
 2013
 Collection
 Electronic Theses & Dissertations
 Description

Microwave PlasmaAssisted Chemical Vapor Deposition (MPACVD) systems are used in the deposition of high quality diamond films. These systems have traditionally been operated at less than 20% atmospheric pressure (atm), resulting in growth rates up to 5 μm/hr. Under such conditions, the system operation and plasma behavior are wellunderstood and have been successfully modeled. Recent experiments at pressures approaching 40% atm have demonstrated faster growth rates and better quality...
Show moreMicrowave PlasmaAssisted Chemical Vapor Deposition (MPACVD) systems are used in the deposition of high quality diamond films. These systems have traditionally been operated at less than 20% atmospheric pressure (atm), resulting in growth rates up to 5 μm/hr. Under such conditions, the system operation and plasma behavior are wellunderstood and have been successfully modeled. Recent experiments at pressures approaching 40% atm have demonstrated faster growth rates and better quality samples. At these increased pressures, the system operation and plasma behavior are not completely understood, with unusual plasma behavior sometimes observed. Experimental measurements within these systems can be difficult, making numerical models attractive for aiding in understanding this behavior. This thesis presents a selfconsistent multiphysics numerical model of MPACVD systems, which is accurate under these operating conditions. Electromagnetic field propagation, chemical reactions, species diffusion, thermal processes, energy transfer, and convective flows are all included in the multiphysics model. The model is verified against canonical problems and validated against experimental data. Extensive numerical results are provided for different operating conditions and system configurations.
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 Title
 Modeling galactic chemical evolution in cosmological simulations
 Creator
 Peruta, Carolyn Cynthia
 Date
 2013
 Collection
 Electronic Theses & Dissertations
 Description

The most fundamental challenges to models of galactic chemical evolution (GCE) are uncertainties in the basic inputs, including the properties of the stellar initial mass function (IMF), stellar nucleosynthetic yields, and the rate of return of mass and energy to the interstellar and intergalactic medium by Type Ia and II supernovae and stellar winds. In this dissertation, we provide a critical examination of widely available stellar nucleosynthetic yield data, with an eye toward modeling GCE...
Show moreThe most fundamental challenges to models of galactic chemical evolution (GCE) are uncertainties in the basic inputs, including the properties of the stellar initial mass function (IMF), stellar nucleosynthetic yields, and the rate of return of mass and energy to the interstellar and intergalactic medium by Type Ia and II supernovae and stellar winds. In this dissertation, we provide a critical examination of widely available stellar nucleosynthetic yield data, with an eye toward modeling GCE in the broad scope of cosmological hydrodynamical simulations. We examine the implications of uncertain inputs for the Galactic stellar IMF, and nucleosynthetic yields from stellarevolution calculations, on our ability to ask detailed questions regarding the observed Galactic chemicalabundance patterns. We find a marked need for stellar feedback data from stars of initial mass 8 to 12 M_{sun} and above 40 M_{sun}, and for initial stellar metallicities above and below solar, Z_{sun}=0.02. We find the largest discrepancies amongst nucleosynthetic yield calculations are due to various groups' treatment of hot bottom burning, formation of the 13C pocket in asymptotic giantbranch (AGB) stars, and details of mass loss, rotation, and convection in all stars. Our model of GCE is used to postprocess simulations to explore in greater detail the nucleosynthetic evolution of the stellar populations and interstellar/intergalactic medium, and to compare directly to the chemical abundances of the Milky Way stellar halo and dwarf spheroidal galaxy stellar populations.
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 Title
 On the adequacy of the Saragon approximation to the normal in econometric models
 Creator
 Kafaei, MohammadAli
 Date
 1984
 Collection
 Electronic Theses & Dissertations
 Title
 Mathematical modeling and simulation of mechanoelectrical transducers and nanofluidic channels
 Creator
 Park, Jin Kyoung
 Date
 2014
 Collection
 Electronic Theses & Dissertations
 Description

Remarkable advances in nanotechnology and computational approaches enable researchers to investigate physical and biological phenomena in an atomic or molecular scale. Smallerscale approaches are important to study the transport of ions and/or molecules through ion channels in living organisms as well as exquisitely fabricated nanofluidic channels. Both subjects have similar physical properties and hence they have common mathematical interests and challenges in modeling and simulating the...
Show moreRemarkable advances in nanotechnology and computational approaches enable researchers to investigate physical and biological phenomena in an atomic or molecular scale. Smallerscale approaches are important to study the transport of ions and/or molecules through ion channels in living organisms as well as exquisitely fabricated nanofluidic channels. Both subjects have similar physical properties and hence they have common mathematical interests and challenges in modeling and simulating the transport phenomena. In this work, we first propose and validate a molecular level prototype for mechanoelectrical transducer (MET) channel in mammalian hair cells.Next, we design three ionic diffusive nanofluidic channels with different types of atomic surface charge distribution, and explore the current properties of each channel. We construct the molecular level prototype which consists of a charged blocker, a realistic ion channel and its surrounding membrane. The Gramicidin A channel is employed to demonstrate the realistic channel structure, and the blocker is a positively charged atom of radius $1.5$\AA\, which is placed at the mouth region of the channel. Relocating this blocker along one direction just outside the channel mouth imitates the opening and closing behavior of the MET channel. In our atomic scale design for an ionic diffusive nanofluidic channel, the atomic surface charge distribution is easy to modify by varying quantities and signs of atomic charges which are equally placed slightly above the channel surface. Our proposed nanofluidic systems constitutes a geometrically welldefined cylindrical channel and two reservoirs of KCl solution. For both the mammalian MET channel and the ion diffusive nanofluidic channel, we employ a wellestablished ion channel continuum theory, PoissonNernstPlanck theory, for three dimensional numerical simulations. In particular, for the nanoscaled channel descriptions, the generalized PNP equations are derived by using a variational formulation and by incorporating nonelectrostatic interactions. We utilize several useful mathematical algorithms, such as Dirichlet to Neumann mapping and the matched interface and boundary method, in order to validate the proposed models with charge singularities and complex geometry. Moreover, the secondorder accuracy of the proposed numerical methods are confirmed with our nanofluidic system affected by a single atomic charge and eight atomic charges, and further study the channels with a unipolar charge distribution of negative ions and a bipolar charge distribution. Finally, we analyze electrostatic potential and ion conductance through each channel model under the influence of diverse physical conditions, including external applied voltage, bulk ion concentration and atomic charge. Our MET channel prototype shows an outstanding agreement with experimental observation of rat cochlear outer hair cells in terms of open probability. This result also suggests that the tip link, a connector between adjacent stereocilia, gates the MET channel. Similarly, numerical findings, such as ion selectivity, ion depletion and accumulation, and potential wells, of our proposed ion diffusive realistic nanochannels are in remarkable accordance with those from experimental measurements and numerical simulations in the literature. In addition, simulation results support the controllability of the current within a nanofluidic channel.
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 Title
 Cross validity of authentic and proxycriterion regression methods in the selection of veterinary school applicants
 Creator
 Stuck, Ivan Alexander
 Date
 1989
 Collection
 Electronic Theses & Dissertations
 Title
 Stochastic modeling of routing protocols for cognitive radio networks
 Creator
 Soltani, Soroor
 Date
 2013
 Collection
 Electronic Theses & Dissertations
 Description

Cognitive radios are expected torevolutionize wireless networking because of their ability tosense, manage and share the mobile available spectrum.Efficient utilization of the available spectrum could be significantly improved by incorporating different cognitive radio based networks. Challenges are involved in utilizing the cognitive radios in a network, most of which rise from the dynamic nature of available spectrum that is not present in traditional wireless networks. The set of available...
Show moreCognitive radios are expected torevolutionize wireless networking because of their ability tosense, manage and share the mobile available spectrum.Efficient utilization of the available spectrum could be significantly improved by incorporating different cognitive radio based networks. Challenges are involved in utilizing the cognitive radios in a network, most of which rise from the dynamic nature of available spectrum that is not present in traditional wireless networks. The set of available spectrum blocks(channels) changes randomly with the arrival and departure of the users licensed to a specific spectrum band. These users are known as primary users. If a band is used by aprimary user, the cognitive radio alters its transmission power level ormodulation scheme to change its transmission range and switches to another channel.In traditional wireless networks, a link is stable if it is less prone to interference. In cognitive radio networks, however, a link that is interference free might break due to the arrival of its primary user. Therefore, links' stability forms a stochastic process with OFF and ON states; ON, if the primary user is absent. Evidently, traditional network protocols fail in this environment. New sets of protocols are needed in each layer to cope with the stochastic dynamics of cognitive radio networks.In this dissertation we present a comprehensive stochastic framework and a decision theory based model for the problem of routing packets from a source to a destination in a cognitive radio network. We begin by introducing two probability distributions called ArgMax and ArgMin for probabilistic channel selection mechanisms, routing, and MAC protocols. The ArgMax probability distribution locates the most stable link from a set of available links. Conversely, ArgMin identifies the least stable link. ArgMax and ArgMin together provide valuable information on the diversity of the stability of available links in a spectrum band. Next, considering the stochastic arrival of primary users, we model the transition of packets from one hop to the other by a SemiMarkov process and develop a Primary Spread Aware Routing Protocol (PSARP) that learns the dynamics of the environment and adapts its routing decision accordingly. Further, we use a decision theory framework. A utility function is designed to capture the effect of spectrum measurement, fluctuation of bandwidth availability and path quality. A node cognitively decides its best candidate among its neighbors by utilizing a decision tree. Each branch of the tree is quantified by the utility function and a posterior probability distribution, constructed using ArgMax probability distribution, which predicts the suitability of available neighbors. In DTCR (Decision Tree Cognitive Routing), nodes learn their operational environment and adapt their decision making accordingly. We extend the Decision tree modeling to translate video routing in a dynamic cognitive radio network into a decision theory problem. Then terminal analysis backward induction is used to produce our routing scheme that improves the peak signaltonoise ratio of the received video.We show through this dissertation that by acknowledging the stochastic property of the cognitive radio networks' environment and constructing strategies using the statistical and mathematical tools that deal with such uncertainties, the utilization of these networks will greatly improve.
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 Title
 Tire models for the determination of vehicle structural loads
 Creator
 Jane, Robert Thomas
 Date
 1981
 Collection
 Electronic Theses & Dissertations
 Title
 Truncated Gaussian process regression for predicting growth of abdominal aortic aneurysm and for temporal modeling of sentiments
 Creator
 Ijaz, Ahsan
 Date
 2013
 Collection
 Electronic Theses & Dissertations
 Description

An abdominal Aortic Aneurysm (AAA) is a form of vascular disease causing focal enlargement of the abdominal aorta. As part of the present study, we use series of computer tomography scans (CTscans) of small AAAs taken at different times to model and predict the spatiotemporal evolution of AAAs. Using the proposed methodology and available CT scan data, the prediction of an AAA can be made for any time using truncated Gaussian process regression. The results of our case study show excellent...
Show moreAn abdominal Aortic Aneurysm (AAA) is a form of vascular disease causing focal enlargement of the abdominal aorta. As part of the present study, we use series of computer tomography scans (CTscans) of small AAAs taken at different times to model and predict the spatiotemporal evolution of AAAs. Using the proposed methodology and available CT scan data, the prediction of an AAA can be made for any time using truncated Gaussian process regression. The results of our case study show excellent outcomes of our algorithms when they are compared to the true CT scan images. Second part of the thesis concerns the temporal modeling of sentiments expressed through textual information in Social networks. As part of this study, we explore the issues related to the temporal models and provide an efficient method which overcomes the inefficiencies associated with traditional schemes. A nonparametric, computationally efficient temporal model is provided using truncated Gaussian process regression. The model is built so that a noise parameter is estimated using the sentiment classification error metrics and inserted in the regression setting. This makes the method generic and any form of quantification of sentiments (through manual labeling or by some other classification scheme) can be used with improvement on final results. Baseline sentiment analysis schemes are used in conjunction with the proposed temporal model on data crawled from Twitter to express the utility of the scheme.
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 Title
 Discrete choice models of hunting and fishing in Michigan
 Creator
 Knoche, Scott
 Date
 2014
 Collection
 Electronic Theses & Dissertations
 Description

In this dissertation I employ multiple discrete choice modeling methods and data collection approaches to make both methodological and empirical contributions which focus on a variety of managementrelevant programs and policies. In dissertation chapter 1, I examine the potential for researchers to estimate recreation demand models using widely available secondary data on recreation site choice that lacks some income and trip details. I find that substituting zipcode median income for...
Show moreIn this dissertation I employ multiple discrete choice modeling methods and data collection approaches to make both methodological and empirical contributions which focus on a variety of managementrelevant programs and policies. In dissertation chapter 1, I examine the potential for researchers to estimate recreation demand models using widely available secondary data on recreation site choice that lacks some income and trip details. I find that substituting zipcode median income for individualreported income, and constructing estimates of trips based on days spent hunting and the distance of the hunting site from the individual's residence, generate welfare estimates that are similar to results using individualreported information on income and trips. This research indicates potential for utilizing a wide range of previously ignored recreation site choice data for recreation demand modeling purposes. Dissertation chapters 2 and 3 are supported by the procedure developed in dissertation chapter 1. Dissertation chapter 2 estimates a discrete choice model of ruffed grouse hunting in Michigan with the objective of estimating both the economic benefits of all publicly accessible hunting land in Michigan for ruffed grouse hunters and the potential changes to ruffed grouse hunter economic benefits as a result of a proposal to ban the use of firearms in approximately 67,000 acres of national forest wilderness area. Economic benefits of publicly accessible hunting land for ruffed grouse hunters in Michigan was estimated to be about $30 million in 2008, with economic benefits of the 67,000 acres of national forest wilderness area to ruffed grouse hunters estimated at about $45,000. Dissertation chapter 3 estimates the economic benefits of the USDA Conservation Reserve Program for pheasant hunters in Michigan by linking a previously developed spatially explicit, landscape based model of pheasant sightings to a discrete choice model of pheasant hunter site choice. Chapter 3 also estimates the potential economic benefits generated through the initiation of a multiagency and stakeholder pheasant habitat restoration plan. Results show that economic benefits for pheasant hunters depend critically on restoration site selection. Dissertation chapter 4 uses a choice experiment survey of Michigan trout anglers to examine the willingness of anglers to make tradeoffs between changes in driving distance to a fishing site and changes in attributes available at fishing sites. On average, trout anglers prefer higher catch rates, shorter travel distances to a fishing site, and are highly averse to strict fishing regulations such as catchandrelease only and artificial flies only regulations. However, there is evidence of preference heterogeneity within the trout angler population for these regulations, with some anglers preferring (all else equal) to fish in areas with these restrictions. This distribution of angler preferences is used to examine the proportion of anglers who can be made better off when strict regulations induce catchrelated quality improvements at a fishing site.
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 Title
 Fast solver for large scale eddy current nondestructive evaluation problems
 Creator
 Lei, Naiguang
 Date
 2014
 Collection
 Electronic Theses & Dissertations
 Description

Eddy current testing plays a very important role in nondestructive evaluations of conducting test samples. Based on Faraday's law, an alternating magnetic field source generates induced currents, called eddy currents, in an electrically conducting test specimen. The eddy currents generate induced magnetic fields that oppose the direction of the inducing magnetic field in accordance with Lenz's law. In the presence of discontinuities in material property or defects in the test specimen, the...
Show moreEddy current testing plays a very important role in nondestructive evaluations of conducting test samples. Based on Faraday's law, an alternating magnetic field source generates induced currents, called eddy currents, in an electrically conducting test specimen. The eddy currents generate induced magnetic fields that oppose the direction of the inducing magnetic field in accordance with Lenz's law. In the presence of discontinuities in material property or defects in the test specimen, the induced eddy current paths are perturbed and the associated magnetic fields can be detected by coils or magnetic field sensors, such as Hall elements or magnetoresistance sensors. Due to the complexity of the test specimen and the inspection environments, the availability of theoretical simulation models is extremely valuable for studying the basic field/flaw interactions in order to obtain a fuller understanding of nondestructive testing phenomena.Theoretical models of the forward problem are also useful for training and validation of automated defect detection systems. Theoretical models generate defect signatures that are expensive to replicate experimentally. In general, modelling methods can be classified into two categories: analytical and numerical. Although analytical approaches offer closed form solution, it is generally not possible to obtain largely due to the complex sample and defect geometries, especially in threedimensional space. Numerical modelling has become popular with advances in computer technology and computational methods. However, due to the huge time consumption in the case of large scale problems, accelerations/fast solvers are needed to enhance numerical models.This dissertation describes a numerical simulation model for eddy current problems using finite element analysis. Validation of the accuracy of this model is demonstrated via comparison with experimental measurements of steam generator tube wall defects. These simulations generating twodimension raster scan data typically takes one to two days on a dedicated eightcore PC. A novel direct integral solver for eddy current problems and GPUbased implementation is also investigated in this research to reduce the computational time.
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 Title
 A constitutive equation for collagen fibers
 Creator
 Haut, Roger Carl, 1944
 Date
 1971
 Collection
 Electronic Theses & Dissertations
 Title
 Near duplicate image search
 Creator
 Li, Fengjie
 Date
 2014
 Collection
 Electronic Theses & Dissertations
 Description

Information retrieval addresses the fundamental problem of how to identify the objects from database that satisfies the information needs of users. Facing the information overload, the major challenge in search algorithm design is to ensure that useful information can be found both accurately and efficiently from large databases.To address this challenge, different indexing and retrieval methods had been proposed for different types of data, namely sparse data (e.g. documents), dense data (e...
Show moreInformation retrieval addresses the fundamental problem of how to identify the objects from database that satisfies the information needs of users. Facing the information overload, the major challenge in search algorithm design is to ensure that useful information can be found both accurately and efficiently from large databases.To address this challenge, different indexing and retrieval methods had been proposed for different types of data, namely sparse data (e.g. documents), dense data (e.g. dense feature vectors) and bagoffeatures (e.g. local feature represented images). For sparse data, inverted index and document retrieval models had been proved to be very effective for large scale retrieval problems. For dense data and bagoffeature data, however, there are still some open problems. For example, Locality Sensitive Hashing, a stateoftheart method for searching high dimensional vectors, often fails to make a good tradeoff between precision and recall. Namely, it tends to achieve high preci sion but with low recall or vice versa. The bagofwords model, a popular approach for searching objects represented bagoffeatures, has a limited performance because of the information loss during the quantization procedure.Since the general problem of searching objects represented in dense vectors and bagoffeatures may be too challenging, in this dissertation, we focus on nearly duplicate search, in which the matched objects is almost identical to the query. By effectively exploring the statistical proper ties of near duplicities, we will be able to design more effective indexing schemes and search algorithms. Thus, the focus of this dissertation is to design new indexing methods and retrieval algorithms, for near duplicate search in large scale databases, that accurately capture the data simi larity and delivers more accurate and efficient search. Below, we summarize the main contributions of this dissertation:Our first contribution is a new algorithm for searching near duplicate bagoffeatures data. The proposed algorithm, named random seeding quantization, is more efficient in generating bagof words representations for near duplicate images. The new scheme is motivated by approximating the optimal partial matching between bagoffeatures, and thus produces a bagofwords representation capturing the true similarities of the data, leading to more accurate and efficient retrieval of bagoffeatures data.Our second contribution, termed Random Projection Filtering, is a search algorithm designed for efficient near duplicate vector search. By explicitly exploiting the statistical properties of near duplicity, the algorithm projects high dimensional vectors into lower dimensional space and filter out irrelevant items. Our effective filtering procedure makes RPF more accurate and efficient to identify nearly duplicate objects in databases.Our third contribution is to develop and evaluate a new randomized range search algorithm for near duplicate vectors in high dimensional spaces, termed as Random Projection Search. Different from RPF, the algorithm presented in this chapter is suitable for a wider range of applications be cause it does not require the sparsity constrains for high search accuracy. The key idea is to project both the data points and the query point into an one dimensional space by a random projection, and perform one dimensional range search to find the subset of data points that are within the range of a given query using binary search. We prove the theoretical guarantee for the proposed algorithm and evaluate its empirical performance on a dataset of 1.1 billion image features.
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 Title
 Marine biosphere diversity through time : provinciality, global shelf area, and sediment survivorship
 Creator
 Eicher, Constance Carolyn
 Date
 1978
 Collection
 Electronic Theses & Dissertations