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Title: EFFECTS OF UNSTEADY AERODYNAMICS ON VERTICAL-AXIS WIND TURBINE PERFORMANCE
Creator: Kozak, Peter
Date: 2014, 2014-05
Description: Vertical-axis wind turbines (VAWTs) o er an inherently simpler design than horizontal-axis machines, while their lower blade speed mitigates...
Show moreVertical-axis wind turbines (VAWTs) o er an inherently simpler design than horizontal-axis machines, while their lower blade speed mitigates safety and noise concerns. As a result, VAWTs can be used to open up more populated areas for large-scale wind energy development. While vertical-axis turbines do o er signi cant operational advantages, development has been hampered by the di culty of mod- eling the aerodynamics involved, along with their rotating geometry. This thesis presents results from a simulation of a baseline VAWT computed using Star-CCM+, a commercial nite volume (FVM) code. Overset grid techniques are used to model the VAWT's complex and moving geometry. VAWT aerodynamics are shown to be dominated at low tip-speed ratios by dynamic stall phenomena and at high tip-speed ratios by wake-blade interactions, using ow visualization and blade angle of attack. An iterative procedure to optimize the VAWT's geometry is developed using blade pitch to mitigate the adverse e ects of dynamic stall for a tip-speed ratio of 2.0 case. Relying on both a constant blade pitch o set as well as a variable blade pitch as a function of azimuthal angle, power output was shown to be increased by 17% and 38%, respectively, compared to the baseline case. Emphasis is placed on the modeling techniques used in the FVM simulation and the optimization process.
M.S. in Mechanical and Aerospace Engineering, May 2014
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Title: AN OPTIMIZATION OF MANUFACTURING PROCESS SELECTION THROUGH COSTING AND SYSTEMATIC ANALYSIS
Creator: Klima, Kevin
Date: 2017, 2017-05
Description: In order for any company to remain competitive, there is a constant push to cut costs while keeping customers satisfied by providing quality,...
Show moreIn order for any company to remain competitive, there is a constant push to cut costs while keeping customers satisfied by providing quality, robust products. While current methods for predicting the most cost effective manufacturing process have proven to offer a significant amount of utility for design engineers, the issue remains that for a cost estimation to be truly accurate, the component has to be completely or nearly completely designed, which could require a significant amount of upfront development time. The goal was to develop a design tool to predict the most cost effective process to manufacture a new component based solely on already available historical data and basic knowledge of the design requirements of the new part. This study focused on steel components that could be manufactured either as a fabrication or as a casting. Two real-world applications were studied from two separate industries, with each application being designed with each process. Common cost estimation techniques were used to develop models for predicting the cost for each component to offer insight for how the cost would be expected to vary with quantity. As a means of ensuring robustness and that each competing model was structurally equivalent, each model had to pass critical exceptional and fatigue load cases in FEA while also meeting predefined success criteria. Using the results from the structural analysis and cost estimation, a design tool was developed as a means of objectively predicting how a component with similar application requirements would most cost effectively be manufactured based on the desired quantity of parts that needed to be produced. By using historical information of similar components that have the possibility of being manufactured in more than one way, more effective and systematic decision making for how a new component should be manufactured was shown to be possible. A third, independent case study was also selected as a real world example from industry as a means of validating and assessing the sensitivity of the weighting used in the development of the design tool. This was used to further refine the tool for the use in analyzing future components.
M.S. in Manufacturing Engineering, May 2017
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Title: ASSESSMENT OF MICROGRIDS FOR DEVELOPED AND DEVELOPING COUNTRIES
Creator: Vyas, Kohil
Date: 2013, 2013-12
Description: Today’s world essentially runs on electricity, in some form or the other. From the introduction of the concept of electricity by William...
Show moreToday’s world essentially runs on electricity, in some form or the other. From the introduction of the concept of electricity by William Gilbert to thousands of invention by Thomas Edison, there have been great changes in the world of electricity. The life of every living being is directly affected by these changes. Various electrical problems have surfaced because of these changes. Microgrids have been considered as a solution to these problems, and have been assessed and evaluated in this research. To realize the effectiveness of microgrids as a solution, initially problems were explored. It was found that there are two perspectives of the problems faced by electrical world. One being: problems seen from the view point of developed countries, and the other: problems seen from the view point of developing countries. Assessment of microgrids was accordingly branched during the research. In the case of the developed countries, the basic infrastructure of electrical system which was built long ago, demands an upgrade now. Problems like blackouts and brownouts have risen and the frequency of their occurrence is growing with time. Owing to these problems, there has been a loss of billions of dollars, as well as critical loads like research facilities, military bases, data centers etc… are severely affected. Microgrids installed in military bases, a university campus and a jail were assessed to analyze how they are implemented, the benefits reaped from them and how they can be a viable solution to the problems faced by the developed countries. In the case of the developing countries, the fact stands that they are yet to reach a state where they can serve their entire load by themselves. This results into regular load shedding. Also, there are some areas where there is no electrical infrastructure and this restricts many from even having xi the access to the electricity. For this research, microgrids installed in villages of Africa, India, and on the islands of Maldives were assessed. Their application and revolutionary impacts on the developing countries were explored. The research indicates that in the developed countries, owing to the gargantuan increase in power consumption, several electrical problems have arisen. Microgrids were able to solve these problems and save millions of dollars. Whereas, in developing countries, people still are in need of a 24-hours access to electricity for their progress. Electricity is required for basic necessities like pumping water, cooking, and activities carried out at night which requires light. Implementation of microgrids by providing electricity removes the bottleneck to their progress.
M.S. in Electrical Engineering, December 2013
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Title: Ease of Contamination and Subsequent Sanitation of Food Contact Surfaces Using Salmonella Contaminated Nut Butters
Creator: Kamineni, Prashanthi
Date: 2012-07-23, 2012-07
Description: Salmonella species can survive and or persist for long periods of time in low moisture foods and on food contact surfaces. Understanding...
Show moreSalmonella species can survive and or persist for long periods of time in low moisture foods and on food contact surfaces. Understanding parameters of transfer and survival can provide information required for successful control of this foodborne microorganism. This study investigated the recovery of Salmonella from food contact surfaces (stainless steel, Delrin, polyethylene, polyurethane) as well as their transfer from nut butters onto the contact surfaces. S. Tennessee and S. Oranienburg were grown overnight to stationary phase, harvested and inoculated separately into peanut butter and almond butter. One gram of inoculated nut butter was applied to each of the three separate 4 X 4 cm areas on the materials and stored at room temperature. The nut butters were removed after 1, 7, and 14 day intervals to leave a visually clean surface. Surfaces were swabbed and/or tested with contact plates to determine the population of any remaining cells. Using contaminated peanut butter, highest numbers of S. Tennessee of about 4.27 ± 0.30 per cm2 were recovered from stainless steel surface after 1 day of contact time. Both serovars were recovered at low numbers over time. However, when contaminated almond butter was used, lower recovery was obtained with both serovars. Visually clean surfaces were also treated with various sanitizers to determine efficiency of treatments. Of the three sanitizers, isopropanol proved most effective overall in reducing Salmonella contamination whereas chlorine was least effective. BDD and isopropanol gave best efficiency on stainless steel with a reduction of about 2.5 logs and least on polyurethane surface with a reduction of only about 1 log (p<0.05). Results were similar for both the serovars tested. In general, sanitizers were most effective on stainless steel while polyurethane surface was the most difficult to sanitize. These studies contribute to a better understanding of the behavior of S. Tennessee and S. Oranienburg in nut butters and on food contact surfaces. Estimation of contamination levels may be determined from transfer rates for Salmonella from contaminated to uncontaminated foods and food contact surfaces.
M.S. in Food Safety and Technology, July 2012
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Title: IMPROVING PEDESTRIAN DETECTION USING OPTICAL FLOW
Creator: Kong, Lingxing
Date: 2015, 2015-12
Description: Pedestrian detection, which has wide applications on surveillance, automatic driving and robotics, plays a significant role in computer vision...
Show morePedestrian detection, which has wide applications on surveillance, automatic driving and robotics, plays a significant role in computer vision. Among all kinds of pedestrian detection methods, stereo based method achieves an accurate and efficient detection result by exploiting depth and color information. However, many stereo based systems fail at considering motion information which is important in locating and detecting an object. For many pedestrian detection systems, adding extra data like motion is one of the most effective ways to improve the performance. Therefore, this thesis proposes a multi-cue pedestrian detection system which integrates optical flow based and stereo based modules for combining motion, depth and color information. In the proposed system, optical flow and disparity value are estimated by using the frames which obtained from a stereo camera. In order to obtain accurate pedestrian motion, ego motion is compensated by using motion clustering, affine model and RANSAC. After that, the motion and the depth information are exploited for ROI generation. Finally, SVM is trained by the combination of motion feature and HOG feature. Experimental results show that the use of high-accuracy optical flow along with depth and color information improves the performance of multi-cue pedestrian detection system.
M.S. in Electrical Engineering, December 2015
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Title: NOVEL 8-T CNFET SRAM CELL DESIGN FOR FUTURE ULTRA-LOW POWER MICROELECTRONICS
Creator: Kim, Youngbae
Date: 2016, 2016-05
Description: In deep sub-micron technology, leakage power consumption has become a major concern in VLSI circuits, especially for SRAM, which is used to...
Show moreIn deep sub-micron technology, leakage power consumption has become a major concern in VLSI circuits, especially for SRAM, which is used to build the cache in System-on-Chip (SOC). In this paper, a low power 8-T SRAM cell, based on carbon nanotube field effect transistor (CNFET), is proposed to circumvent the leakage power issue. Experiment datas show that the proposed SRAM cell can save 97.94% static power consumption compared to existing 6T CNFET SRAM cell. In case of writing, the proposed SRAM cell consumes 39.27% less power than the traditional SRAM cell for writing 0 and 58.79% less for writing 1. Also, because of the adoption of a colaborated voltage sense amplifier and independent read component, our 8T SRAM shows much improved delay performance, the delay is observed to reduce by approximate 30% in write operation and approximate 90% in read operation.
M.S. in Electrical Engineering, May 2016
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Title: LIPID-LIPID AND LIPID-DRUG INTERACTIONS IN BIOLOGICAL MEMBRANES
Creator: Martynowycz, Michael W.
Date: 2016, 2016-07
Description: Interactions between lipids and drug molecules in biological membranes help govern proper biological function in organisms. The mechanisms...
Show moreInteractions between lipids and drug molecules in biological membranes help govern proper biological function in organisms. The mechanisms responsible for hydrophobic drug permeation remain elusive. Many small molecule drugs are hydrophobic. These drugs inhibit proteins in the cellular interior. The rise of antibiotic resistance in bacteria is thought to be caused by mutations in protein structure, changing drug kinetics to favor growth. However, small molecule drugs have been shown to have different mechanisms depending in the structure of the lipid membrane of the target cell. Biological membranes are investigated using Langmuir monolayers at the airliquid interface. These offer the highest level of control in the mimetic system and allow them to be investigated using complementary techniques. Langmuir isotherms and insertion assays are used to determine the area occupied by each lipid in the membrane and the change in area caused by the introduction of a drug molecule, respectively. Specular X-ray re ectivity is used to determine the electron density of the monolayer, and grazing incidence X-ray diffraction is used to determine the inplane order of the monolayer. These methods determine the affinity of the drug and the mechanism of action. Studies are presented on hydrophobic drugs with mammalian membrane mimics using warfarin along with modified analogues, called superwarfarins. Data shows that toxicity of these modified drugs are modulated by the membrane cholesterol content in cells; explaining several previously unexplained effects of the drugs. Membrane mimics of bacteria are investigated along with their interactions with a hydrophobic antibiotic, novobiocin. Data suggests that permeation of the drug is mediated by modifications to the membrane lipids, and completely ceases translocation under certain circumstances.
Ph.D. in Physics, July 2016
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Title: ACOUSTICAL ANALYSIS OF A SMALL PERFORMANCE HALL
Creator: Masoner, Ashley
Date: 2012-04-19, 2012-05
Description: This thesis studies the acoustics of a 793 seat multi-use theater. The theater is a fan shaped hall with acoustical properties that the...
Show moreThis thesis studies the acoustics of a 793 seat multi-use theater. The theater is a fan shaped hall with acoustical properties that the building owners found to be wanting. The acoustics were first measured using eight microphones and a frequency-sweepproducing source. The measured reverberations were then used to design and calibrate a model of the space in CATT, an acoustical modeling program, after which a variety of other unmeasured qualities of the space were calculated from the CATT model. This information was used to design a plan to improve the acoustics of the theater; the hall’s volume was increased by moving the back balcony wall farther back in order to increase the reverberation, the ceiling was reshaped in order to more evenly distribute the first order reflected rays to the audience, and some of the walls were resurfaced to alter the frequency effects of the walls. All these alterations are feasible from an engineering perspective. The proposed changes were then modeled in CATT to confirm they would have the desired effects.
M.S. in Civil Engineering, May 2012
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Title: THE RELATIONSHIP BETWEEN ATTRIBUTIONAL STYLE, DEPRESSION, AND ACCEPTANCE OF DISABILITY IN CHINESE INDIVIDUALS WITH SPINAL CORD INJURY
Creator: Heyne, Mark Michael
Date: 2011-03-27, 2011-05
Description: The positive relationship between negative attributional style and depression has been established in both those with and without chronic...
Show moreThe positive relationship between negative attributional style and depression has been established in both those with and without chronic illness or physical disability; however, this relationship remains uncharacterized in those with spinal cord injury (SCI), which is surprising, given this condition’s significant potential for negative psychosocial implications. Although there is evidence that the association among these two variables generalizes across cultures and disabilities, other findings suggests that the Chinese have a more negative attributional style than their Western counterparts, which could alter the relationship between attributional style and depression among Chinese with SCI. Likewise, the construct of acceptance of disability (AD) and its correlates has been covered extensively in Western samples with SCI, but has received virtually no attention in Eastern samples. The present study examined these variables within the context of SCI in a Chinese sample. Participants were 158 Chinese individuals with SCI who completed a battery of self-report measures of demographic, injury-related, and psychosocial variables. Cluster analysis results suggested three distinct clusters based on attributional style (positive, neutral, negative). Those in the positive attributional style cluster were more likely to have tetraplegia than paraplegia, but exhibited less functional disability and depressive symptoms, and higher AD than the negative cluster. Path analysis indicated that higher functional disability predicted both more negative attributional style and higher depressive symptomology; attributional style did not directly predict depression, in contrast to findings from previous studies. Higher depressive symptomology was found to predict lower AD, consistent with existing research.
Ph.D. in Psychology, May 2011
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Title: SELF-HEALING IN MICROGRID OPERATION AND MESSAGE-PASSING BASED DEMAND RESPONSE
Creator: Barati, Masoud
Date: 2013, 2013-12
Description: Electrical energy can be more efficiently and reliably generated, transmitted, and consumed over electricity grids as smart grids evolve....
Show moreElectrical energy can be more efficiently and reliably generated, transmitted, and consumed over electricity grids as smart grids evolve. Through the two-way flow of information between suppliers and consumers, the grids can encourage and adapt more easily to the increased consumer participation in energy management through demand response. This dissertation studies the transactive energy management on the residential side via microgrid operation and message-passing based demand response. A microgrid is an independent section of the electrical distribution grid with capabilities to transmit, produce, and distribute power within a localized area. The implementation of the microgrid increases the reliability and quality of power supply through various means including the self-healing paradigm. A microgrid operating under a self-healing paradigm can automatically and intelligently detect and reroute the power flow around an unexpected line fault. This dissertation presents the formulations and the methodologies of the self-healing process, which is incorporated into the microgrid operation for real-time scheduling. The self-healing process tries to find the best topology of the microgrid including radial and closed-loop configurations that minimize the total operation cost while respecting all security constraints. The dissertation also considers the AC solution of optimal power flow for self-healing applications, which enhances the reactive power flow for mitigating any bus voltage violations and for alleviating any real and reactive loop flows. The message-passing based demand response scheme relies on dynamic pricing of electricity to regulate electricity consumption. To achieve this goal, load serving entities via messages-passing gather the information such as consumers’ usage of electricity from xv ii smart meters, and set the dynamic price level appropriately in order to reduce the peak electricity demand through the cooperation of customers. In response to the dynamic price signals, customers can shift their demands automatically, with the help of a home energy management system, or manually to the off-peak hours so as to minimize their electricity payment and maximize its utility function. The message-passing based demand response scheme is applied in this dissertation to residential household scheduling, which is a key component of a future smart grid that can help reduce peak loads and adjust elastic demands to provide economic and emergency demand responses. A decentralized and iterative message-passing method is developed for solving the residential household scheduling problem. Under the context of a competitive retail electricity market, this dissertation analytically models load serving entities’ production function based on wellknown economic theory, analytically models household behaviors based on the ordinal and cardinal concepts of the utility function and using a static game strategy, and efficiently calculates retail electricity price with pure ex-ante or combinatorial pricing strategies. A simple yet effective price stabilization strategy for retail electricity price is proposed to mitigate the potential price and consumption spike caused by uncertainties in wholesale electricity prices.
PH.D in Electrical Engineering, July 2013
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Title: PANCREATIC ADENOCARCINOMA: SECRETORY MARKERS AND CORRELATION WITH PARKINSON’S DISEASE
Creator: Gayatri, Sitaram
Date: 2011-04-27, 2011-05
Description: Pancreatic adenocarcinoma (PDAC), the fourth highest cause of cancer related deaths in the United States, has the most aggressive presentation...
Show morePancreatic adenocarcinoma (PDAC), the fourth highest cause of cancer related deaths in the United States, has the most aggressive presentation resulting in a very short median survival time for the affected patients. Early detection of PDAC is confounded by lack of specific markers. Proteins of importance in neurodegenerative diseases like Parkinson’s disease (PD) are believed to be of etiological significance and correlated to or be the cause/effect of pancreatic disease. Expression of proteins like PD autosomal recessive, early onset 7 (PARK-7/DJ-1), α-Synuclein (SNCA) both of which are known to be pathognomonic to Parkinson’s disease was found altered in various stages of the disease. Purine Nucleoside Phosphorylase (NP) has been exploited to be a therapeutic target in cancers. The expression of all these three proteins was found to be variable with the stage and existence of metastatic lesions in PDAC tissues. The protein levels of NP were higher in PDAC sera compared to the benign samples. The serum NP levels of other cancers viz. lung, kidney, colon and breast were also not elevated. While the serum levels of NP and those of its downstream metabolites have the potential to differentiating PDAC from benign, the expression levels of SNCA and PARK-7/DJ-1 allude to a possible nuance in the etiology of PD and PDAC.
M.S. in Biology, May 2011
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Title: THE PATH TO HIGH Q-FACTORS IN SUPERCONDUCTING ACCELERATING CAVITIES: FLUX EXPULSION AND SURFACE RESISTANCE OPTIMIZATION
Creator: Martinello, Martina
Date: 2016, 2016-12
Description: Accelerating cavities are devices resonating in the radio-frequency (RF) range used to accelerate charged particles in accelerators....
Show moreAccelerating cavities are devices resonating in the radio-frequency (RF) range used to accelerate charged particles in accelerators. Superconducting accelerating cavities are made out of niobium and operate at the liquid helium temperature. Even if superconducting, these resonating structures have some RF driven surface resistance that causes power dissipation. In order to decrease as much as possible the power losses, the cavity quality factor must be increased by decreasing the surface resistance. In this dissertation, the RF surface resistance is analyzed for a large variety of cavities made with different state-of-the-art surface treatments, with the goal of finding the surface treatment capable to return the highest Q-factor values in a cryomodule-like environment. This study analyzes not only the superconducting properties described by the BCS surface resistance, which is the contribution that takes into account dissipation due to quasi-particle excitations, but also the increasing of the surface resistance due to trapped flux. When cavities are cooled down below their critical temperature inside a cryomodule, there is always some remnant magnetic field that may be trapped increasing the global RF surface resistance. This thesis also analyzes how the fraction of external magnetic field, which is actually trapped in the cavity during the cooldown, can be minimized. This study is performed on an elliptical single-cell horizontally cooled cavity, resembling the geometry of cavities cooled in accelerator cryomodules. The horizontal cooldown study reveals that, as in case of the vertical cooldown, when the cooling is performed fast, large thermal gradients are created along the cavity helping magnetic flux expulsion. However, for this geometry the complete magnetic flux expulsion from the cavity equator is more difficult to achieve. This becomes even more challenging in presence of orthogonal magnetic field, that is easily trapped on top of the cavity equator causing temperature rising. The physics behind the magnetic flux expulsion is also analyzed, showing that during a fast cooldown the magnetic field structures, called vortices, tend to move in the same direction of the thermal gradient, from the Meissner state region to the mixed state region, minimizing the Gibbs free energy. On the other hand, during a slow cool down, not only the vortices movement is limited by the absence of thermal gradients, but, also, at the end of the superconducting transition, the magnetic field concentrates along randomly distributed normal-conducting region from which it cannot be expelled anymore. The systematic study of the surface resistance components performed for the different surface treatments, reveals that the BCS surface resistance and the trapped flux surface resistance have opposite trends as a function of the surface impurity content, defined by the mean free path. At medium field value, the BCS surface resistance is minimized for nitrogen-doped cavities and significantly larger for standard niobium cavities. On the other hand, Nitrogen-doped cavities show larger dissipation due to trapped flux. This is consequence of the bell-shaped trend of the trapped flux sensitivity as a function of the mean free path. Such experimental findings allow also a better understanding of the RF dissipation due to trapped flux. The best compromise between all the surface resistance components, taking into account the possibility of trapping some external magnetic field, is given by light nitrogen-doping treatments. However, the beneficial effects of the nitrogen-doping is completely lost when large amount of magnetic field is trapped during the cooldown, underlying the importance of both cooldown and magnetic field shielding optimization in high quality factors cryomodules.
Ph.D. in Physics, December 2016
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Title: KINETIC PARAMETERS SENSITIVITY ANALYSIS OF THE CALUMET WATER RECLAMATION PLANT USING GPS-X
Creator: Mao, Xiangzhou
Date: 2015, 2015-07
Description: It is an important objective to find equilibrium between cost and effluent water quality at the Calumet water reclamation plants (WRP)....
Show moreIt is an important objective to find equilibrium between cost and effluent water quality at the Calumet water reclamation plants (WRP). Kinetic parameters of activated sludge process have significant influence on effluent water quality. In this study, based on a simulation model, sensitivity analysis methods were used to assess the effects of six kinetic parameters on dissolved oxygen, carbonaceous biochemical oxygen demand (CBOD5), and effluent ammonia concentration. According to the values of kinetic parameter, two cases: ±10% perturbation of the typical default value and full parameter range were studied. Results presented that main effects have important effects on the output variables. Heterotrophic maximum specific growth rate, heterotrophic decay rate, autotrophic maximum specific growth rate, autotrophic decay rate, and maximum specific hydrolysis rate have relatively significant sensitivity. In addition, the influences of the interactions among kinetic parameters are discussed. Keys words: Kinetic parameters; sensitivity analysis; water reclamation plants; dissolved oxygen; CBOD5; ammonia
M.S. in Environmental Engineering, July 2015
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Title: The manufacture of salicylic acid
Creator: Kendall, S. W.
Date: 2009, 1917
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/manufactureofsal00kend
Thesis (B.S.)--Armour Institute of Technology

Title: Manufacture of soaps and the recovery of glycerine
Creator: Polhman, E.f., Martin, H.w.
Date: 2009, 1910
Publisher: Armour Institute of Technology
Description: http://www.archive.org/details/manufactureofsoa00polh
Thesis (B.S.)--Armour Institute of Technology

Title: MODELING AND SIMULATION OF DIRECT CARBON FUEL CELL ANODE IN CONNECTION WITH ANALYSIS AND CHARACTERIZATION OF WETTED CARBON ROD IN MOLTEN CARBONATE
Creator: Peng, Feng
Date: 2013, 2013-07
Description: Not available
M.S. in Chemical Engineering, July 2013

Title: NETWORK-LEVEL VEHICLE CRASH PREDICTIONS INCORPORATING TIME-DEPENDENT EFFECTS INTO CONSIDERATIONS
Creator: Dao, Hoang
Date: 2016, 2016-07
Description: Maintaining highway safety is viewed as the over-arching goal of mananging transportation systems at all levels. According to the National...
Show moreMaintaining highway safety is viewed as the over-arching goal of mananging transportation systems at all levels. According to the National Highway Traffic Safety Administration (NHTSA), over 37,000 people got killed and 2.35 million are injured in road crashes annually. The equivalent economic and societal losses are on the order of over $231 billion, or an average of $820 per person. Thus, developing vehicle crash models that can accurately predict crash occurrences becomes essential. The study begins with literature review of models for predicting vehicle crash frequencies and crash severity levels on highway segments and at highway intersections. The findings of literature review indicate that some models lack prediction accuracy owing to exclusion of many crashing contributing factors. Consequently, a new methodology for improved vehicle crash predictability is proposed to include as many crash contributing factors as possible. In addition, the proposed methodology aims to conduct crash predictions targeting a highway network. Two computational experiments are performed for methodology application, including one on highway segment-related crash predictions using data on Highway Safety Information System for Illinois from 2001 to 2010, and another one on intersection-related crash predictions using crash data on more than one thousand intersections for period 2004 to 2010 provided by city of Chicago. Cross comparisons are made on the results obtained by applying the proposed methodology, method documented in Highway Safety Manual (AASHTO, 2010), and Empirical Bayesian (EB) before-after method for validation. The proposed methodology is found to have out-performed the other two methods. Future research directions are provided for continuing refinements of the proposed methodology.
Ph.D. in Civil Engineering, July 2016
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Title: THE ROLE OF EXPERIENTIAL AVOIDANCE IN THE ASSOCIATION BETWEEN ANXIETY SENSITIVITY AND EMOTIONAL EATING IN NON-EATING DISORDERED OVERWEIGHT/OBESE INDIVIDUALS SEEKING WEIGHT LOSS TREATMENT BY
Creator: Dave, Pooja N.
Date: 2015, 2015-12
Description: Obesity is one of the most rapidly emerging public health concerns whose prevalence far exceeds that of eating disorders (Hudson et al., 2007)...
Show moreObesity is one of the most rapidly emerging public health concerns whose prevalence far exceeds that of eating disorders (Hudson et al., 2007). As most obese individuals do not meet criteria for an eating disorder, emotional eating (EE) may be a more useful construct in understanding obesity more broadly. Anxiety sensitivity (AS) has been recognized as a transdiagnostic risk factor for a variety of problem behaviors including EE in obese individuals (Hearon et al., 2012). In addition, recent research has highlighted the mediating role of maladaptive responses to internal experiences in the association between AS and eating pathology (Anestis et al., 2008). Experiential avoidance (EA) is one such maladaptive response that has garnered attention for predicting maladaptive coping for a range of psychiatric conditions. To date, only one study has examined the relationship between AS and EE in obese individuals (Hearon et al., 2012). This study aims to replicate and extend their findings by examining the role of EA in this relationship. A sample of 127 obese patients without an eating disorder seeking weight-loss treatment completed questionnaires to assess emotional eating, experiential avoidance, and anxiety sensitivity. When controlling for gender, negative affect, and current psychiatric diagnosis and treatment, EA was found to fully mediate the relationship between AS and EE. There was a significant positive indirect effect (B = .285, CI95% = .155-.462) and a non-significant direct effect (B = .039, p = .786. These findings provide initial support for the mediating role of EA in the association between AS and EE in an obese, non-eating disordered, weight-loss treatment-seeking sample.Further, the identification of AS and EA as relevant in the development of emotional eating adds to the growing literature base arguing for the conceptualization of these two factors as transdiagnostic risk factors for a wide range of problem behaviors, including emotional eating. Clinical and research implications are discussed, as well as strengths and limitations of the study. Recommendations for the development of interventions targeting individuals high in anxiety sensitivity, with the intention of reducing experiential avoidance, are also reviewed.Further, the identification of AS and EA as relevant in the development of emotional eating adds to the growing literature base arguing for the conceptualization of these two factors as transdiagnostic risk factors for a wide range of problem behaviors, including emotional eating. Clinical and research implications are discussed, as well as strengths and limitations of the study. Recommendations for the development of interventions targeting individuals high in anxiety sensitivity, with the intention of reducing experiential avoidance, are also reviewed.
Ph.D. in Psychology, December 2015
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Title: ELECTRIC VEHICLE (EV) STORAGE SUPPLY CHAIN RISK AND THE ENERGY MARKET: A MICRO AND MACROECONOMIC RISK MANAGEMENT APPROACH
Creator: Aguilar, Susanna D.
Date: 2015, 2015-12
Description: NO ABSTRACT
Ph.D. in Management Science, December 2015

Title: POSTMORTEM MRI OF THE ELDERLY HUMAN BRAIN: METHODS AND APPLICATIONS TO HISTOPATHOLOGICALLY VERIFIED ALZHEIMER’S DISEASE AND OTHER NEUROPATHOLOGIES OF AGING
Creator: Dawe, Robert J.
Date: 2011-04-08, 2011-05
Description: Currently, a definitive diagnosis of Alzheimer’s disease is only possible postmortem, when the distribution and type of pathology in the brain...
Show moreCurrently, a definitive diagnosis of Alzheimer’s disease is only possible postmortem, when the distribution and type of pathology in the brain can be directly verified via histology. Clinical diagnostic techniques in use today rely on behavioral and neuropsychological criteria and only provide diagnoses of possible or probable Alzheimer’s disease, both of which indicate that significant irreversible neuronal damage has already occurred. Therefore, a neuroimaging technique for detection of Alzheimer’s pathology during life is highly sought after. Such a technique would be noninvasive, could provide a quantitative evaluation of potential therapies in patients, and could eventually be used for early detection of Alzheimer’s disease. The purpose of this work was to investigate the use of magnetic resonance imaging (MRI) as diagnostic tool for Alzheimer’s and other types of pathology that are common in the elderly human brain. In order to correlate imaging data with a diagnosis of neuropathology that was guaranteed to be accurate, we focused on imaging cerebral hemispheres postmortem (ex vivo), when a complete pathology report was available from a board-certified neuropathologist. The main difference between this work and any other study is the abundance of postmortem imaging data paired with neuropathology data in a relatively large pool of subjects. First, we examined the relation between postmortem hippocampal volume, measured from MR images, and pathological diagnosis of Alzheimer’s and other common types of pathology. It was shown that Alzheimer’s, along with hippocampal sclerosis, are associated with a dramatic reduction in hippocampal volume. Furthermore, the pattern of hippocampal atrophy differs between these two types of neuropathology, which may provide a means of distinguishing one from the other in vivo using MR images. Next, the transverse relation time constant, T2, was examined over time in five postmortem hemispheres that were undergoing chemical fixation via immersion in formaldehyde solution. This investigation yielded two important pieces of information: (a) for the purposes of obtaining stable measurements of T2, the ideal time to conduct postmortem MRI of the human brain is at least one month postmortem, and (b) correction of T2 measurements for the postmortem interval to imaging is both possible and necessary for analysis of T2 alterations associated with pathology. Using the information gleaned from the study of changes in transverse relaxation over time, we next examined the dependence of T2 on the presence of Alzheimer’s pathology. Significant prolongation of T2 was demonstrated in various white matter regions in cases of Alzheimer’s, suggesting degeneration of that tissue. Significant shortening of T2 was detected in the basal ganglia, suggesting that accumulation of iron in that region is associated with the progression of Alzheimer’s disease. Finally, a method of conducting high quality diffusion tensor MRI of postmortem cerebral hemispheres was developed. Compared to in vivo diffusion tensor MRI, the postmortem variant of the technique is much more challenging, since the signal to noise ratio is affected very negatively by a combination of faster transverse relaxation, reduced water diffusivity, and the resulting need for longer diffusion-sensitizing gradients. To a large extent, these problems have been solved, and we have now implemented a protocol for routine diffusion tensor MRI of recently deceased human brains which takes less than one hour of scan time. This work examined three MRI techniques that hold great promise in their ability to detect Alzheimer’s and other types of neuropathology: hippocampal volumetry, mapping of the transverse relaxation time constant T2, and diffusion tensor imaging. The fact that all three techniques were carried out postmortem is an important contribution, since it allows for imaging results to be correlated with a complete and accurate pathological diagnosis of disease. Findings from postmortem studies could one day be translated to the in vivo case, where they can potentially be used for antemortem diagnosis of Alzheimer’s disease.
Ph.D. in Biomedical Engineering, May 2011
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