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 Title
 A novel algorithm of solvation free energy calculation : the KECSAmovable type implicit solvation model (KMTISM)
 Creator
 Wang, Ting (M.S. in Chemistry)
 Date
 2015
 Collection
 Electronic Theses & Dissertations
 Description

A number of theoretical methods have been developed for calculating solvation free energies for biological and chemical processes. In this paper an implicit solvation model, KECSAMovable Type Implicit Solvation Model (KMTISM)
is created by utilizing an energy sampling approach termed the “Movable Type” (MT) method, and
a statistical energy function for solvation modeling, “Knowledgebased and Empirical
Combined Scoring Algorithm” (KECSA). The solvation free energies can be obtained from the...
Show moreA number of theoretical methods have been developed for calculating solvation free energies for biological and chemical processes. In this paper an implicit solvation model, KECSAMovable Type Implicit Solvation Model (KMTISM) is created by utilizing an energy sampling approach termed the “Movable Type” (MT) method, and a statistical energy function for solvation modeling, “Knowledgebased and Empirical Combined Scoring Algorithm” (KECSA). The solvation free energies can be obtained from the NVT ensemble partition function generated by the MT method within the implicit solvent model approximation. Several subsets from the Minnesota Solvation Database v2012 are selected to use as validation sets. The solvation free energies getting from KMTISM are compared with several solvation free energy calculation methods, including MMGBSA and MMPBSA. Comparison against a quantum mechanicsbased polarizable continuum model is also discussed (Cramer and Truhlar’s Solvation Model 12).
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 Title
 Modeling and simulation of strongly coupled plasmas
 Creator
 Chowdhury, Rahnuma Rifat
 Date
 2016
 Collection
 Electronic Theses & Dissertations
 Description

The objective of this work is to develop new modeling and simulation tools for studying strongly coupled plasmas (SCP). Strongly coupled plasmas are different from traditional plasmas as potential energy is larger than the kinetic energy. The standard plasma model does not account for some major effects in SCP: 1) the change in the permittivity 2) the impact on relaxation of the charged particles undergoing Coulomb collisions in a system with weakly shielded long range interactions3) the...
Show moreThe objective of this work is to develop new modeling and simulation tools for studying strongly coupled plasmas (SCP). Strongly coupled plasmas are different from traditional plasmas as potential energy is larger than the kinetic energy. The standard plasma model does not account for some major effects in SCP: 1) the change in the permittivity 2) the impact on relaxation of the charged particles undergoing Coulomb collisions in a system with weakly shielded long range interactions3) the impact of statistical fluctuations in strongly coupled plasmas that leads to nonMarkovian effects. Proper modeling of such systems through consideration of Lévy flight processes gives rise to fractional derivatives in time that result in an incorporation of time history in the model. A Lévy flight is a random walk in which the steps are defined in terms of the steplengths, which have a certain probability distribution, with the directions of the steps being isotropic and random. Lévy processes in the plasma give rise to fluctuations in medium through which the electromagnetic waves are propagating. Averaging over the Lévy processes will allow us to relate to other important parameters in the plasma.
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 Title
 Semiparametric models for mouthlevel indices in caries research
 Creator
 Yang, Yifan
 Date
 2016
 Collection
 Electronic Theses & Dissertations
 Description

For nonnegative count responses in health services research, a large proportion of zero counts are frequently encountered. For such data, the frequency of zero counts is typically larger than its expected counterpart under the classical parametric models, such as Poisson or negative binomial model. In this thesis, a semiparametric zeroinflated regression model is proposed for count data that directly relates covariates to the marginal mean response representing the desired target of...
Show moreFor nonnegative count responses in health services research, a large proportion of zero counts are frequently encountered. For such data, the frequency of zero counts is typically larger than its expected counterpart under the classical parametric models, such as Poisson or negative binomial model. In this thesis, a semiparametric zeroinflated regression model is proposed for count data that directly relates covariates to the marginal mean response representing the desired target of inference. The model specifically assumes two semiparametric forms: the loglinear form for the marginal mean and the logisticlinear form for the susceptible probability, in which the fully linear models are replaced with partially linear link functions. A splinebased estimation is proposed for the nonparametric components of the model. Asymptotic properties are discussed for the estimators of the parametric and nonparametric components of the models. Specifically, the estimators are shown to be strong consistent and asymptotically efficient under mild regularity conditions. A bootstrap hypothesis test is performed to evaluate difference involving the nonparametric component. Simulation studies are conducted to evaluate the finite sample performance of the model. Finally, the model is applied to dental caries indices in low income AfricanAmerican children to evaluate the nonlinear effects of sugar intake on caries development. The conclusion shows that the effect of sugar intake on caries indices is nonlinear, especially among young children under the age of 2. And children whose caregivers are unemployed and have poor oral healthy exhibit higher dental caries rates.
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 Title
 Modeling the impacts of barrier removal on Great Lakes sea lamprey
 Creator
 Jensen, Alexander James
 Date
 2017
 Collection
 Electronic Theses & Dissertations
 Description

Barriers in the Great Lakes represent an effective form of control for the invasive sea lamprey (Petromyzon marinus) by blocking large extents of river habitat and subsequently eliminating the need for the lampricide treatments in these upstream areas. With increasing pressure for barrier removals, the availability of suitable sea lamprey habitat above these barriers and the expected population response to dam removals represent key uncertainties in decisionmaking. The development and...
Show moreBarriers in the Great Lakes represent an effective form of control for the invasive sea lamprey (Petromyzon marinus) by blocking large extents of river habitat and subsequently eliminating the need for the lampricide treatments in these upstream areas. With increasing pressure for barrier removals, the availability of suitable sea lamprey habitat above these barriers and the expected population response to dam removals represent key uncertainties in decisionmaking. The development and evaluation of models to predict larval habitat quantities using readilyavailable, reachscale landscape predictors improved our understanding of common influences on stream habitat, but failed to reliably predict habitat proportions upstream of barriers in the Lake Michigan drainage basin. Subsequent simulationbased modeling of the Lake Michigan sea lamprey population revealed a disproportionate, exponential response to increasing habitat availability, driven in part by decreasing overall lampricide treatment frequencies under a fixed control budget. The same modeling approach was used to generate sea lamprey population predictions associated with projected removal of Grand River's Sixth Street Dam under a suite of alternative management actions and biological assumptions. Based on all simulation results, barrier removals appear to necessitate a substantial increase in annual lampricide control costs to prevent disproportionate increases in sea lamprey abundance across the Lake Michigan basin.
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 Title
 Modelbased estimation of AMT vehicle clutch kinetic friction coefficient
 Creator
 He, Yu (Graduate of Michigan State University)
 Date
 2018
 Collection
 Electronic Theses & Dissertations
 Description

Driving performance and fuel economy are two important factors that attracts customers choosing certain type of vehicles. Those two factors can be improved largely by adopting optimized transmission gearshifting strategy. The kinetic clutch friction coefficient is important to know to develop an optimized gearshifting algorithm.This thesis focus on estimating dynamic kinetic friction coefficient between two clutch plats of an automated manual transmission (AMT) vehicle when speed and...
Show moreDriving performance and fuel economy are two important factors that attracts customers choosing certain type of vehicles. Those two factors can be improved largely by adopting optimized transmission gearshifting strategy. The kinetic clutch friction coefficient is important to know to develop an optimized gearshifting algorithm.This thesis focus on estimating dynamic kinetic friction coefficient between two clutch plats of an automated manual transmission (AMT) vehicle when speed and temperature effects are involved. A Simulink model of an AMT vehicle was developed first, and a new friction coefficient estimation algorithm was then proposed and validated based on the developed Simulink model. Several case studies are completed for the proposed estimation algorithm and fairly good simulation results are presented at the end of thesis.
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 Title
 Further investigation of a kinetic model to accurately predict evaporation of gasoline
 Creator
 Eklund, Natasha Kimberley
 Date
 2019
 Collection
 Electronic Theses & Dissertations
 Description

In fire debris analysis, analysts compare chromatograms of extracts of fire debris to a database containing chromatograms of ignitable liquid reference standards. Typically, the database will contain chromatograms of experimentally evaporated liquids. Unfortunately, experimentally evaporating ignitable liquids can be a timeconsuming process. Previously, a mathematical model was developed with diesel that predicts the evaporation rate constant of compounds as a function of retention index (IT...
Show moreIn fire debris analysis, analysts compare chromatograms of extracts of fire debris to a database containing chromatograms of ignitable liquid reference standards. Typically, the database will contain chromatograms of experimentally evaporated liquids. Unfortunately, experimentally evaporating ignitable liquids can be a timeconsuming process. Previously, a mathematical model was developed with diesel that predicts the evaporation rate constant of compounds as a function of retention index (IT). The model can be used to generate predicted chromatograms of evaporated liquids. In comparing predicted to experimental chromatograms, predictive accuracy was high for comparisons using diesel, torch fuel, and marine fuel stabilizer.This research aims to improve the predictive accuracy of the model with respect to gasoline and to test the feasibility of developing correlation coefficient ranges for the classification of an ignitable liquid residue as gasoline. Improvement of the predictive accuracy of the model involved changes to the instrumental parameters and data analysis procedures. The feasibility of development of PPMC coefficient ranges involved comparisons of predicted reference collections of a nongasoline ignitable liquid to chromatograms of experimentally evaporated gasoline.
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 Title
 Dynamic boundary guarding against radially incoming targets
 Creator
 Bajaj, Shivam
 Date
 2019
 Collection
 Electronic Theses & Dissertations
 Description

In this modern era, every physical asset can be defined by a perimeter and guarding these perimeters is critical from a security and safety perspective. Recent growth in autonomous vehicle technology has led to assigning these monotonous tasks to the autonomous vehicles. This assignment requires design of a set of motion laws for these autonomous vehicles that are both effective and efficient, with provable bounds. This thesis focuses on designing of strategies for a single autonomous vehicle...
Show moreIn this modern era, every physical asset can be defined by a perimeter and guarding these perimeters is critical from a security and safety perspective. Recent growth in autonomous vehicle technology has led to assigning these monotonous tasks to the autonomous vehicles. This assignment requires design of a set of motion laws for these autonomous vehicles that are both effective and efficient, with provable bounds. This thesis focuses on designing of strategies for a single autonomous vehicle to intercept multiple targets. In this work, we introduce a dynamic vehicle routing problem in which a single vehicle seeks to guard a circular perimeter against radially inward moving targets. The aim of the vehicle is to maximize the capture fraction, i.e., the fraction of targets intercepted before they enter the perimeter. We first obtain a fundamental upper bound on the capture fraction which is independent of any policy followed by the vehicle. We analyze several policies in the low and high arrival rates of target generation. For low arrival, we propose and analyze a FirstComeFirstServed and a LookAhead policy based on repeated computation of the path that passes through maximum number of unintercepted targets. For high arrival, we design and analyze a policy based on repeated computation of Euclidean Minimum Hamiltonian path through a fraction of existing targets and show that it is within a constant factor of the optimal. Finally, we provide a numerical study of the performance of the policies in parameter regimes beyond the scope of the analysis.
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 Title
 An analysis of the risk and risk reduction of influenza virus infection through use of antimicrobial products
 Creator
 Chabrelie, Alexandre
 Date
 2019
 Collection
 Electronic Theses & Dissertations
 Description

Influenza is a pathogen of major concern, causing up to 79,000 deaths, 960,000 hospitalizations, and 49 million people sick per year in the US. One of the major route of transmission for influenza is by expelling viruses from coughing/sneezing onto surfaces, followed by transfer of viruses from surfaces to hands, and subsequently to facial mucous membranes.Therefore, routine cleaning and disinfection of surfaces is an important part of the environmental management of influenza A. While the...
Show moreInfluenza is a pathogen of major concern, causing up to 79,000 deaths, 960,000 hospitalizations, and 49 million people sick per year in the US. One of the major route of transmission for influenza is by expelling viruses from coughing/sneezing onto surfaces, followed by transfer of viruses from surfaces to hands, and subsequently to facial mucous membranes.Therefore, routine cleaning and disinfection of surfaces is an important part of the environmental management of influenza A. While the emphasis is generally on spraying hard surfaces and laundering cloth and linens with high temperature machine drying, not all surfaces can be treated in this manner. The quantitative microbial risk assessment (QMRA) approach was used to develop a stochastic risk model for estimating the risk of infection from indirect contact with porous surfaces, with and without surface pretreatment with an antimicrobial spray product. The data collected from laboratory combined with the risk model show that the risk of influenza A infection can be lowered by four logs when using an antimicrobial spray on a porous surface. Median risk associated with a single touch to a contaminated fabric was estimated to be 1.25 x104 for the untreated surface, and 3.6 x108 for the treated surface. This single touch scenario was used to develop a generalizable model, allowing to estimate risks by comparing different cases related to more realistic 15 to 30 minutes exposure scenarios associated with multiple surface/face touches. The results of this study demonstrate the effective risk reduction associated with treating porous surfaces that cannot be laundered at high temperatures.
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 Title
 Kinetically modeling total ion chromatograms and extracted ion profiles to identify ignitable liquids for fire debris applications
 Creator
 Capistran, Briana Ashley
 Date
 2020
 Collection
 Electronic Theses & Dissertations
 Description

Identification of ignitable liquids in fire debris samples is typically conducted via comparison of total ion chromatograms (TICs) of such samples to reference collections containing chromatograms of common liquids. Due to the extent of liquid evaporation in fires, reference collections often contain TICs of ignitable liquids that have been experimentally evaporated to various levels; however, such evaporations can be time intensive. A kinetic model was developed to predict evaporation rate...
Show moreIdentification of ignitable liquids in fire debris samples is typically conducted via comparison of total ion chromatograms (TICs) of such samples to reference collections containing chromatograms of common liquids. Due to the extent of liquid evaporation in fires, reference collections often contain TICs of ignitable liquids that have been experimentally evaporated to various levels; however, such evaporations can be time intensive. A kinetic model was developed to predict evaporation rate constants of compounds as a function of GC retention index. The model can be applied to predict chromatograms of ignitable liquids at any evaporation level, alleviating the need to perform experimental evaporations. Previous work demonstrated good predictive accuracy of the model for petroleum distillate liquids and gasoline.In this work, the kinetic model was applied to ignitable liquids of the isoparaffinic, naphthenicparaffinic, and aromatic ASTM classes. Predicted extracted ion profiles (EIPs) were generated in addition to TICs for each liquid, and good predictive accuracy of the model was demonstrated with PPMC coefficients as high as 0.9983. Reference collections containing predicted TICs and EIPs were generated. The TICs and EIPs of singleblind samples and largescale burn samples were compared to the reference collections; in all cases, the correct ASTM liquid class was identified. Use of the EIP reference collection for the burn samples resulted in higher correlation compared to the TIC collection due to reduced substrate interferences. Overall, this work demonstrates the utility of a kinetic model for generating predicted reference collections as a tool in the identification of ignitable liquids for fire debris applications.
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