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Pages
- Title
- Marine biosphere diversity through time : provinciality, global shelf area, and sediment survivorship
- Creator
- Eicher, Constance Carolyn
- Date
- 1978
- Collection
- Electronic Theses & Dissertations
- Title
- Lake model uncertainty analysis : a Lake Ontario case study using Monte Carlo simulation
- Creator
- Lee, V. David
- Date
- 1980
- Collection
- Electronic Theses & Dissertations
- Title
- Tire models for the determination of vehicle structural loads
- Creator
- Jane, Robert Thomas
- Date
- 1981
- Collection
- Electronic Theses & Dissertations
- Title
- Use of concurrent tasks for effective structural control modeling
- Creator
- Wolschon, Mark Edward
- Date
- 1993
- Collection
- Electronic Theses & Dissertations
- Title
- Experimental determination of a spinal linkage model for the seated human torso
- Creator
- Gedraitis, Melissa Sloan
- Date
- 1997
- Collection
- Electronic Theses & Dissertations
- Title
- Modeling maize (Zea mays L.) leaf development and apex temperature under different thermal environments
- Creator
- Vinocur, Marta Graciela
- Date
- 1997
- Collection
- Electronic Theses & Dissertations
- Title
- The relevance of the electoral system : a simulation of the 1992 Kenyan election
- Creator
- Ndegwa, Stephen N.
- Date
- 1997-06
- Collection
- African Journal of Political Science
- Description
-
In the recent political transitions in Africa competitive elections have become the most critical events in the allocation of power. However, little attention has been given to the design of electoral systems, that is, the rules used to determine the allocation of parliamentary seats and of the presidential office. With few exceptions, plurality and majority systems are assumed to be the simplest, natural, and most democratic systems of converting votes into seats. This paper explores...
Show moreIn the recent political transitions in Africa competitive elections have become the most critical events in the allocation of power. However, little attention has been given to the design of electoral systems, that is, the rules used to determine the allocation of parliamentary seats and of the presidential office. With few exceptions, plurality and majority systems are assumed to be the simplest, natural, and most democratic systems of converting votes into seats. This paper explores alternative electoral systems for apportioning seats in parliament and for securing the presidency. Specifically, it simulates outcomes in the 1992 Kenyan general elections using a proportional representation system in the parliamentary elections and a preferential ballot system in the presidential contest. The overriding normative goal is "fair representation," especially given ethnically-driven electoral behavior. The simulations reported here offer possible outcomes that could have emerged had different electoral rules been used in the 1992 elections. Given both the data used and the conditions prevailing in the 1992 elections, the specific outcome of each simulation is valid only as a demonstration and a discussion tool.
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- Title
- A fictitious domain solver for computation of the effective properties of material distributions generated by iterated affine maps
- Creator
- Brennan, Edward M.
- Date
- 2000
- Collection
- Electronic Theses & Dissertations
- Title
- Diffusion of physical and social inclusion within local public park and recreation agencies in Michigan
- Creator
- Rodriguez, Ariel
- Date
- 2002
- Collection
- Electronic Theses & Dissertations
- Title
- Numerical integration of constitutive models applicable to metal foams
- Creator
- Modi, Abhishek
- Date
- 2004
- Collection
- Electronic Theses & Dissertations
- Title
- Typed caching and server problems
- Creator
- Porcelli, Martin Douglas
- Date
- 2007
- Collection
- Electronic Theses & Dissertations
- Title
- Analysis and design of resonant frequency control systems with applications
- Creator
- Smith, Daniel
- Date
- 2007
- Collection
- Electronic Theses & Dissertations
- Title
- Replicating natural tree stand patterns in a northern Michigan rock outcrop landscape : a fractal based method and application for reforesting a reclaimed Michigan surface mine
- Creator
- Lehmann, Wade J.
- Date
- 2009
- Collection
- Electronic Theses & Dissertations
- Title
- Quantitative comparison of aluminum alloy sheet forming methods
- Creator
- Venkatesan, Senthilkumar
- Date
- 2010
- 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 (CT-scans) of small AAAs taken at different times to model and predict the spatio-temporal 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 (CT-scans) of small AAAs taken at different times to model and predict the spatio-temporal 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
- Experimental and mathematical models for Listeria monocytogenes transfer between delicatessen meats and contact surfaces
- Creator
- Benoit, Amanda Nicole
- Date
- 2013
- Collection
- Electronic Theses & Dissertations
- Description
-
Currently, there is limited ability to follow Listeria monocytogenes through food-service environments, and there remain knowledge gaps concerning the underlying mechanisms that govern surface-to-surface transfer processes. Therefore, the objectives were to: (1) develop a method to quantify the spread of a physical surrogate, GloGermTM powder (GGP), between delicatessen meats and contact surfaces, and mathematically relate that to L. monocytogenes transfer under equivalent...
Show moreCurrently, there is limited ability to follow Listeria monocytogenes through food-service environments, and there remain knowledge gaps concerning the underlying mechanisms that govern surface-to-surface transfer processes. Therefore, the objectives were to: (1) develop a method to quantify the spread of a physical surrogate, GloGermTM powder (GGP), between delicatessen meats and contact surfaces, and mathematically relate that to L. monocytogenes transfer under equivalent conditions; and (2) aggregate existing transfer data and compare candidate models across different transfer scenarios to elucidate phenomenological differences attributable to contact surface or product type. GGP and L. monocytogenes inoculated pieces (8 x 8 cm), of turkey, ham, stainless steel, or high-density polyethylene were placed in contact with an uninoculated surface of an opposite material (i.e., meat vs. equipment surface) for 12 sequential transfers. The GGP curves (photographed and quantitatively analyzed via image processing) were fit to the corresponding L. monocytogenes data by a linear adjustment, noting that parameters for recipient surfaces did not differ significantly (P > 0.05). Linear, Weibull, and two-phase linear- Weibull models were fitted to transfer curves encompassing the major ready-to-eat meat products, equipment surfaces, and contact events. The most likely models were determined using the Akaike Information Criterion. For slicing data, model choice was product dependent, but static contact data yielded the same model regardless of the meat type or surface, indicating fundamental differences among transfer responses.
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- Title
- A stochastic multi-scale model of stream-groundwater interaction in strongly heterogeneous porous medium and its application in southern Branch County, Michigan
- Creator
- Xinyu, Ye
- Date
- 2014
- Collection
- Electronic Theses & Dissertations
- Description
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In this paper, stream depletion is assessed by the approach of multi-scale geostatistics in stressed watershed, South Branch County, Michigan. The watershed is currently under large water demand and representative of the general failure to pass the online Water Withdrawal Assessment Tool. Due to the heterogeneity of porous medium and the high variability of hydrogeological parameters and scale, there is a deviation between field observations and simulated groundwater flow in those areas. The...
Show moreIn this paper, stream depletion is assessed by the approach of multi-scale geostatistics in stressed watershed, South Branch County, Michigan. The watershed is currently under large water demand and representative of the general failure to pass the online Water Withdrawal Assessment Tool. Due to the heterogeneity of porous medium and the high variability of hydrogeological parameters and scale, there is a deviation between field observations and simulated groundwater flow in those areas. The approach of multi-scale geostatistics model based on detailed lithological data and its application in numerical groundwater simulation can be used in stream depletion assessment. Specifically, the multi-scale transition probability geostatistics approach, supplemented with a 10m Digital Elevation Model, allows for a more realistic integration of heterogeneous medium into the development of correlated spatial variability of hydrogeological parameters at each spatial scale. This approach enables accurate simulation of complex hydrogeology, including vertical shift structural variation and aquifer thickness variations. Systematic hydrology models at the regional, local and site scale allows for simulations of integrated water budget analysis. These simulations are necessary to evaluate the water depletions of targeted streams and the surrounded protected area. The hydrology system is calibrated with the steady state water levels from 732 monitoring wells.The stability of transition probability geostatistics model depends on the distributions, the heterogeneity of simulated area and other factors. The results show that transition probability geostatistics model provides a reasonable distribution of materials in aquifer medium, improving numerical groundwater modeling in assessing water depletion in streams and venerable area.
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- Title
- A mathematical model for predicting optimal micro-perforated packaging
- Creator
- Zhang, Jin (Graduate of Michigan State University)
- Date
- 2015
- Collection
- Electronic Theses & Dissertations
- Description
-
Micro-perforated packaging has been known to maintain the quality of fresh produceby increasing gas exchange volume through polymer films. Even though by far severalmathematical models have been proposed to predict gas exchange process of micro perforated films, to the best of author's knowledge, there are no statistical methods usedto analyze the models themselves. Therefore, the aim of this research was to employinverse problem technique (ordinary least square, sequential and bootstrap...
Show moreMicro-perforated packaging has been known to maintain the quality of fresh produceby increasing gas exchange volume through polymer films. Even though by far severalmathematical models have been proposed to predict gas exchange process of micro perforated films, to the best of author's knowledge, there are no statistical methods usedto analyze the models themselves. Therefore, the aim of this research was to employinverse problem technique (ordinary least square, sequential and bootstrap methods) tomodel gas exchange process of micro-perforated packaging based on a different approach, and to assess the validity of the prediction. The prediction model involved hydrodynamic flow (minor head loss theory) and diffusion flow (total pressure gradient ≠0). To better predict hydrodynamic flow, the entrance shape of micro perforations was analyzed under SEM. To test the prediction model, experimental data sets were evaluated together with a published data set. The predicted results had high agreement with both data groups, and all the predicted values fell within the asymptotic and bootstrap confidence and prediction bands showing the reliability of the model. Besides, the condition number (cond(J) =1) and bootstrap residual analysis further verified the validity of the model. Due to the slight difference from the reference boundary values, parameters in the model were also accurately estimated by inverse problem technique.
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- Title
- Microbial fuel cells : design, control-oriented modeling, and experimental results
- Creator
- Abul, Ali
- Date
- 2015
- Collection
- Electronic Theses & Dissertations
- Description
-
There is no doubt about how crucial to have sustainable energy in this era. Researchers focus on fuel cells because of their high efficiency, environmental friendliness, and independence from limited sources, etc. Microbial fuel cell (MFC) is a promising technology that responds to the demand of sustainable energy. MFCs, similar to other fuel cells, use catalysts and produce electricity through chemical reactions during substrate break-down. In this case, MFCs use bacteria as the catalysts to...
Show moreThere is no doubt about how crucial to have sustainable energy in this era. Researchers focus on fuel cells because of their high efficiency, environmental friendliness, and independence from limited sources, etc. Microbial fuel cell (MFC) is a promising technology that responds to the demand of sustainable energy. MFCs, similar to other fuel cells, use catalysts and produce electricity through chemical reactions during substrate break-down. In this case, MFCs use bacteria as the catalysts to break down the organic matter. There have been control studies on fuel cells, specifically on hydrogen fuel cells, for various purposes. Because MFCs are still not well understood, similar control studies have not been adequately conducted. In this study, a control-oriented mathematical model for MFC dynamics is developed and analyzed. An MFC system is designed and developed, which has successfully demonstrated production of electricity. Experiments are conducted to identify the model parameters and validate the model. For the MFC prototype, \textit{G. sulfurreducens} strain PCA is used as the pure bacteria culture with the acetate as the substrate. The MFC used in this study adopts a membrane-less single-chamber configuration, and utilizes an air-cathode and a carbon-brush anode.Once the model is developed, the behavior of an MFC is analyzed using system theory. In particular, the equilibria of the system in the continuous mode, where the MFC is fed with the substrate at a constant rate are computed. Furthermore, Jacobian analysis and phase portraits are used to understand the stability properties of the equilibria.
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- Title
- Speed control of Permanent Magnet Synchronous Motor using extended high-gain observer
- Creator
- Alfehaid, Abdullah Ahmad
- Date
- 2015
- Collection
- Electronic Theses & Dissertations
- Description
-
Feedback linearization is used to regulate and shape the speed of a surface mount Permanent Magnet Synchronous Motor (PMSM). An extended high-gain observer, which is driven by the measured position of the PMSM’s rotor, is also used to estimate both the speed of the motor and the disturbance present in the system to recover the performance of feedback linearization. Two methods are presented to design the extended high-gain observer. The first method is based on the full model of the PMSM and...
Show moreFeedback linearization is used to regulate and shape the speed of a surface mount Permanent Magnet Synchronous Motor (PMSM). An extended high-gain observer, which is driven by the measured position of the PMSM’s rotor, is also used to estimate both the speed of the motor and the disturbance present in the system to recover the performance of feedback linearization. Two methods are presented to design the extended high-gain observer. The first method is based on the full model of the PMSM and the second method is based on a reduced model of the PMSM. The reduction of the model is made possible by creating fast current loops that allowed the use of singular perturbation theory to replace the current variables by their quasi-steady-state equivalent. The design of the speed controller and the extended high-gain observer is based on the nominal parameters of the PMSM. The disturbance is assumed to be unknown, and time-varying but bounded. Stability of the output feedback system is shown. Finally, simulation and experimental results confirm stability, robustness, and performance of the system.
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