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Title: THE LATIN AMERICAN EXPORT: IMPLEMENTING LATIN AMERICAN URBAN STRATEGIES TO REDEVELOP AND RECONSTRUCT BRONZEVILLE
Creator: Saldaña Perales, Alejandro
Date: 2018
Description: The district and neighborhood of Bronzeville, located in the Near South Side of Chicago, suffers from crime, unemployment, abandonment, and...
Show moreThe district and neighborhood of Bronzeville, located in the Near South Side of Chicago, suffers from crime, unemployment, abandonment, and urban decay; more so than many of its metropolitan peers such as New York City, Los Angeles, or San Francisco.In Latin America, multidisciplinary operations and strategies focused on the investment in public spaces, mobility, and public assets have been successful in transforming decaying neighborhoods and redeveloping slums and blighted areas turning them into vibrant communities.Contextualizing and abstracting such strategies has the potential to import such ideas into new urban contexts; in this case, the United States of America, and to be implemented over the decaying North American urban fabric.
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Title: Implicit ligand theory: binding free energy calculations based on multiple rigid receptor snapshots
Creator: Xie, Bing
Date: 2018
Description: Binding affinity plays an important role in drug design. Accurate and fast prediction of binding free energies remains a major challenge for...
Show moreBinding affinity plays an important role in drug design. Accurate and fast prediction of binding free energies remains a major challenge for structure-based calculation. We have developed a fast free energy calculation program AlGDock and applied it to different systems. In this thesis, I will first demonstrate the feasibility of estimating protein-ligand binding free energies using multiple rigid receptor configurations on T4 lysozyme. Based on 576 snapshots extracted from six alchemical binding free energy calculations with a flexible receptor, binding free energies were estimated for a total of 141 ligands. For 24 ligands, the calculations reproduced flexible-receptor estimates with a correlation coefficient of 0.90 and a root mean square error of 1.59 kcal/mol. The accuracy of calculations based on Poisson-Boltzmann/Surface Area implicit solvent was comparable to previously reported free energy calculations. Then we evaluate a number of common snapshot selection strategies using a quality metric from stratified sampling, the efficiency of stratification, which compares the variance of a selection strategy to simple random sampling. For docking sets of over five hundred ligands to four different proteins of varying flexibility, we observe that for estimating ensemble averages and exponential averages, many clustering algorithms have similar performance trends: for few snapshots (less than 25), medoids are the most efficient while for a larger number, optimal (the allocation that minimizes the variance) and proportional(to the size of each cluster) allocation become more efficient. Proportional allocation appears to be the most consistently efficient for estimating minima. Finally, we attempted a blinded prediction challenge D3R and applied AlGDock on several systems. I will describe the performance of our calculation. Overall, the study shows that AlGDock can work well for predicting the binding affinities and it demonstrates a strategy for developing an understanding of protein-ligand interactions.
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Title: Critical Aspect Ratio And Flow Development In A Low Reynolds Number Variable Aspect Ratio Duct Utilizing Oil Film Interferometry
Creator: Chiu, Daniel P.
Date: 2019
Description: Within the realm of fluid mechanics, there has always been an interest of bridging the gap between ideal- and real fluid flows. Pertaining to...
Show moreWithin the realm of fluid mechanics, there has always been an interest of bridging the gap between ideal- and real fluid flows. Pertaining to the study of turbulent duct flow, an aspect ratio (AR) configuration that would behave in such a manner would be considered a critical aspect ratio. This would mean the flow core would be unaffected by any sidewall contributions. Such analysis is done through wall shear measurement techniques; this study used oil-film interferometry (OFI).The first steps of this study were to determine sufficient criteria to ensure that the data collected were representative of the tested configuration, e.g. parameter choice and flow development length. Previous studies used the bulk velocity U_b which is derived from the entirety of the flow. This study focuses on the flow core, thus the choice to use the center-line velocity U_C seemed appropriate. The development length pertains to testing downstream from the inlet such that parameters are independent in th`e streamwise direction. This study demonstrates that the previously held value of x/H = 100 is insufficient and that nearly twice that is required.Furthermore, this study shows three very important findings: the flow development length required for testing is x/H ≈ 200, the size of the test platform plays little part in the overall behavior of the flow, and that the critical aspect ratio is AR = 24. These findings correspond to an aspect ratio range of 12.8 ≤ AR ≤ 48 and a Reynolds number range of 0.5 × 10^4 < Re_H < 4.0 × 10^4 . From these data, the estimated relationship between the coefficient of friction and the Reynolds number is shown with the following relation:Cf,C = 0.05164 Re_H ^ −0.25
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Title: MODELING THE ORIGIN AND INCEPTION OF FATIGUE FAILURE IN METALS THROUGH A NON-LINEAR MECHANICAL SPRING SYSTEM
Creator: Divani, Abbas
Date: 2019
Description: Fatigue failure of metals is one of the aspects of material behavior that have not been explained through direct calculations or mathematical...
Show moreFatigue failure of metals is one of the aspects of material behavior that have not been explained through direct calculations or mathematical modeling. This research is to undertake the development of an innovative model that can be used in predicting the fatigue behavior of metals. This model is based on the behavior of a system of large number of parallel elements, each composed of two springs, a string, and a mass block, that undergo cyclically varying or random load cycles. Failures among the elements occur at random and can be used as a means to simulate fatigue damage and fatigue behavior. Initial studies on this model have produced promising results. This research is intended for full development and implementation of the model including procedures for Development of a method for calibration of the model parameters using the common mechanical properties of steel, extension of the model to incorporate the hysteresis behavior of steel under cycling loading, and development of Constant Fatigue Life diagrams Such as Goodman diagram.
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Title: SUSTAINED RELEASE OF PHOSPHATE-BASED THERAPEUTICS FOR ATTENUATION OF PATHOGEN-INDUCED PROTEOLYTIC MATRIX DEGRADATION
Creator: Bittencourt Pimentel, Marja
Date: 2019
Description: Loss of the normal intestinal microbiome community structure and its replacement by pathogenic microbes contributes to severe persistent...
Show moreLoss of the normal intestinal microbiome community structure and its replacement by pathogenic microbes contributes to severe persistent inflammation in diseases such as ulcerative colitis and inflammatory bowel disease. While host-derived proteases are known to contribute to this pathogenesis, the role of increased production of microbial-secreted proteases due to virulent phenotypes remains unclear. Following surgical removal of diseased intestinal tract, increased bacterial protease expression is a key phenotype involved in intestinal healing impairment. Antibiotic administration is ineffective for treating these complications as it inadvertently eliminates normal flora while allowing pathogenic bacteria to acquire antibiotic resistance. Prior research has shown that intestinal phosphate depletion in the surgically stressed host triggers bacterial virulence which is suppressed under phosphate abundant conditions. To address this issue our previous work has demonstrated that the use of free monophosphate (-Pi) and polyphosphate (-PPi), as well as post-loaded PPi nanoparticles (NP-PPi) attenuate collagenase production of gram-negative (Pseudomonas aeruginosa and Serratia marcescens) but not gram-positive (Enterococcus faecalis) pathogens expressing high collagenolytic activity. Due to the variation in phosphate metabolism among microbial species we investigated the in vitro efficacy of a combination treatment of phosphates delivered in a sustained release format using NP-PPi and NP-Pi on collagenase and biofilm attenuation across gram-positive and gram-negative test pathogens.Collagenase screening was assessed using two in vitro models. The first in vitro assay involved culturing pathogens in the presence and absence of NP-Pi and/or NP-PPi treatment using two-dimensional (2D) commercially available fluorogenic protease-sensitive peptide substrates. Although these substrates are among the most commonly used for screening protease activity and inhibition in vitro, their application does not translate to three-dimensional (3D) matrix degradation. Additionally, the addition of drug-loaded nanoparticles directly in bacterial culture does not recapitulate the in vivo sustained release of phosphates due to nanoparticles embedded within tissue. Thus, the second model involved the development of a novel cell culture platform which utilized a proteolytically degradable hydrogel scaffold and a non-degradable nanocomposite hydrogel scaffold. In this assay NP-Pi and NP-PPi were entrapped in a non-degradable poly(ethylene) glycol (PEG) hydrogel to form of a nanocomposite matrix which served as a reservoir for sustained release of phosphates. Bacteria producing high levels of proteases were cultured in the presence of the nanocomposite phosphate releasing reservoir and the proteolytically degradable PEG hydrogel scaffold to determine the efficacy of sustained release of phosphates in attenuating proteolytic hydrogel degradation. To correlate matrix degradation with bacterial enzymes secreted in the culture medium, we also developed a method to efficiently measure hydrogel degradation rate until complete material degradation with a greater degree of accuracy compared to the commonly employed method utilizing gravimetric measurements in gel wet weight. Combined, the in vitro platform and our proposed degradation assay provide a novel approach for screening the effect of therapeutics for attenuation of bacterial protease-induced matrix degradation.The 2D in vitro study demonstrated that the combination treatment (NP-PPi + NP-Pi) confers broad spectrum efficacy for suppression of collagenase and biofilm production across test pathogens. Conversely, the 3D in vitro model demonstrated that the combination treatment (NP-PPi + NP-Pi) attenuated protease production for gram-negative pathogens, while the gram-positive test pathogen exhibited significant decreases in protease levels only in the presence of NP-Pi. Finally, our novel Sirius red absorbance assay for quantifying hydrogel degradation was found to provide greater accuracy when compared to gravimetric measurements in gel wet weight. It also enabled real-time monitoring of 3D matrix degradation kinetics as well as the time required for complete material dissolution in the presence of bacterial proteases and active human MMP-9 enzyme solutions. These findings highlight the importance of designing relevant in vitro platforms for screening therapeutic efficacy in the presence of cells and nanomaterials.
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Title: Leakage Power Attack-Resilient Designs of A SRAM Cell in 7nm FinFET Technology
Creator: Chen, Kangqi
Date: 2019
Description: Recently, the classic metal-oxide-semiconductor field-effect-transistor (MOS- FET) has reached its limit for scaling. Another transistor...
Show moreRecently, the classic metal-oxide-semiconductor field-effect-transistor (MOS- FET) has reached its limit for scaling. Another transistor structure, FinFET, gradually has become the alternative choice for next generation of integrated circuits. Excellent features like reduced short channel effects, low threshold-voltage variability, less random dopant fluctuation, etc, offer this transistor model more stability, less leakage and faster performance. In particular, scaling trends force SRAM cells to be more vulnerable while using conventional MOSFET. The application of FinFET helps SRAM cell designs to overcome stability issues and achieve less power and faster speed. Another critical feature of an SRAM cell that needs to be considered is the correlation between data stored in cell and leakage of this cell. Side-Channel Attacks (SCA) like Leakage Power Analysis (LPA) would exploit this correlation to decrypt the secret key inside the memory. SCA has been proved to be a non-invasive but dangerous threat. Therefore, LPA would be the main focus of this thesis research.In this thesis, firstly, threshold voltage of various models are investigated using fundamental logic circuits including full-adders built with pass transistors, CLRCL and SERF. Secondly, conventional 6T SRAM cell design and single-ended 9T SRAM cell design targeting high stability and low power, are implemented and compared. Thirdly, the leakage balance method is applied to 9T cell design. Two novel solutions for LPA prevention of 9T design are proposed, implemented and compared against the original 9T design and conventional 6T design. The results confirm improved leakage balance and attack resilience while maintaining the stability and low-power features of the original 9T SRAM cell.
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Title: Simple Entropy Terms for End-Point Binding Free Energy Calculations
Creator: Menzer, William Michael
Date: 2019
Description: We introduce a number of computationally inexpensive modifications to the MM/PBSA and MM/GBSA estimators for binding free energies, which are...
Show moreWe introduce a number of computationally inexpensive modifications to the MM/PBSA and MM/GBSA estimators for binding free energies, which are based on average receptor−ligand interaction energies in simulations of a noncovalent complex, to improve the treatment of entropy: second- and higher-order terms in a cumulant expansion and a confining potential on ligand external degrees of freedom. We also consider a filter for snapshots where ligands have drifted from the initial binding pose. The variations were tested on six sets of systems for which binding modes and free energies have previously been experimentally determined. For some data sets, none of the tested estimators led to results significantly correlated with measured free energies. In data sets with nontrivial correlation, a ligand RMSD cutoff of 3 Å and a second-order truncation of the cumulant expansion was found to be comparable or better than the average interaction energy by several statistical metrics.
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Title: SHARING COMMUNITY HOUSING YOUNG PROFESSIONALS IN CHINESE BIG CITIES
Creator: ZHANG, HAOYU
Date: 2018
Description: In the past few decades, China has achieved an unbelievable fast development, from a poor after-war country to the second largest economy in...
Show moreIn the past few decades, China has achieved an unbelievable fast development, from a poor after-war country to the second largest economy in the world. Under the leadership of the Chinese central government and people’s corporate effort, China made significant achievements in its economic growth, modernization construction. With these achievements, Chinese urbanization has gone through a rapid development and expansion process. Nowadays, city living quality and urban development became one of the most popular focal points in Chinese people’s daily life.The Chinese urbanization enters rapid expansion era. Urbanization with Chinese characteristics does bring a rich material life and improve the standard of people’s living. Meanwhile, city problems started to appear and bring inexpediency and troubles to urban resident’s daily life. At the same time when cities are developing, the distance between people seems to get further. Comparing to other groups of people, the young professionals, are facing more challenges in the cities. They are under pressure from intense competition and high living cost. Most of them must live in space with bad conditions and gradually lose confidence under the heavy load from life. They are also in self-enclosed status, losing normal social relationships and scare to communicate with others. In Chinese big cities, having a comfortable space to live and not being lonely seems to be an unattainable wish for the young generation. Meanwhile, as an emerging economic pattern, Sharing Economy started to appear in most countries of the world during past years. China, as one of the largest economies, and a country with extremely high population base and rapid development speed became the best place for sharing economy to be developed. The Chinese urbanization situation gave a massive push to the sharing economy which is highly expected and considered to be able to solve the problem of conflict between people and urban. This thesis aims to prove that the idea of sharing can create an efficient, economical and comfortable living environment for young professionals in Chinese big cities, by looking at the urbanization with Chinese characteristics, young professionals living conditions, the development of sharing economy in China and developing a community prototype. This community will help young people to relieve living stress and rebuild social connections, also become a solution to reduce the conflict between young professionals and urban environment.
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Title: Hutong Skyscraper high-rise studio
Creator: Zhang, He
Date: 2012-05-02, 2012-05

Title: INVESTIGATION OF OXIDATIVE DEGRADATION AND DEGRADATION MITIGATION IN POLYMER ELECTROLYTE FUEL CELLS USING IN-SITU FLUORESCENCE SPECTROSCOPY
Creator: Prabhakaran, Venkateshkumar
Date: 2014, 2014-05
Description: Hydrogen/air polymer electrolyte fuel cells (PEFCs) possess high efficiency and modularity. However, significant technical advances are...
Show moreHydrogen/air polymer electrolyte fuel cells (PEFCs) possess high efficiency and modularity. However, significant technical advances are required to facilitate their commercialization in targeted applications. A key issue is component durability under an array of adverse operating conditions. The polymer electrolyte membrane (PEM) in a PEFC is one of the components whose long-term durability is of concern since it undergoes mechanical, thermal, and chemical degradation during fuel cell operation. The chemical (oxidative) degradation processes that take place in a PEM are attributed to reactive oxygen species (ROS) that are generated in-situ during PEFC operation. It is essential to quantify the rate of ROS generation within the PEM during PEFC operation prior to proposing an effective degradation mitigation strategy. This is a daunting challenge, given the high reactivity and very short lifetime of these species. The rate of generation of ROS within the PEM of an operating PEFC was accurately measured, for the very first time, using in-situ fluorescence spectroscopy. The influence of fuel cell operating parameters (temperature, relative humidity, and electrode potential/current density) on the rate of ROS generation was studied. The ROS generation reaction rate constant (estimated from the in-situ fluorescence experiments) correlated perfectly with the macroscopic rate of PEM degradation (estimated from the ex-situ fluoride emission rate) across all conditions, demonstrating unequivocally for the first time that a direct correlation existed between in-situ ROS generation and PEM macroscopic degradation. The utility of using regenerative free radical scavengers (FRS) such as CeO2 nanoparticles to mitigate ROS induced PEM degradation was also demonstrated using xxii xxii in-situ fluorescence spectroscopy. Though CeO2 was shown to scavenge the generated ROS, its scavenging efficacy declined with time and hence it was not truly a regenerative scavenger. The FRS efficacy was found to scale with the number of surface oxygen vacancies in its non-stoichiometric lattice. The regenerative FRS activity of CeO2 nanoparticles was improved by tuning its lattice via nitrogen doping (N-doping). It was demonstrated that N-doping increased both the number of Ce3+ active clusters in the lattice and the Ce-O bond distance; these structural attributes enhanced the regenerative ROS scavenging activity of CeO2. In addition, the influence of catalyst support on PEM degradation during PEFC operation was studied. A novel and highly corrosion-resistant non-carbon catalyst support (RuO2-SiO2; RSO) developed by our group was compared against a benchmark carbonbased catalyst support (Vulcan XC 72; C). It was found that the ROS generation rate, and hence the macroscopic PEM degradation rate, was lower when RSO was used as the electrocatalyst support in place of C. In conjunction with its remarkable corrosionresistance, this finding further illustrated the viability of RSO as an outstanding PEFC electrocatalyst support. Apart from PEM degradation, the applications of fluorescence spectroscopy in the context of other electrochemical devices was also discussed. Proofof- concept studies to study the Pt dissolution rate (in PEFC electrodes) and vanadium crossover rate (in vanadium redox flow batteries) were successfully undertaken; these areas, along with probing degradation processes secondary batteries, would be rich grounds for future study.
PH.D in Chemical Engineering, May 2014
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Title: WIND TURBINE FARMS IMPACT ON POLLEN TRANSPORT DISPERSION PATTER S
Creator: Hsu, Chin Yu
Date: 2012-11-28, 2012-12
Description: Wind energy has become more and more popular because electricity generation by wind power brings much less environmental impacts than...
Show moreWind energy has become more and more popular because electricity generation by wind power brings much less environmental impacts than conventional energy generation using coal. Also, energy generated by wind power does not require expensive fuel imported from overseas. Since the land in between turbines is still cultivated for crops and grazing, it is important to know the potential interference of wind turbines with pollen transport and dispersion, or the possible change of patterns established for thousands of years. However, these issues have not been studied in the literature. The co-existence of conventional crops with genetically modified (GM) crops has become a subject of debate. In particular, pollen transfer from GM crops to non-GM crops might result in the introgression of transgenes into natural populations as maize is mainly wind-pollinated. This study thus reports and assesses a comprehensive method that estimates maize pollen transport in the presence of turbines to ascertain the potential for maize pollen transport. The study on the concentrations of maize pollen transport affected by the wind turbines considers different dispersion parameters given the additional mechanical turbulence introduced by the presence of operating wind turbines. For instance, the wind turbines can increase surface roughness which subsequently causes increased mechanical turbulence. A high mechanical turbulence subsequently reduces downwind concentrations because of the mixing higher and wider into the atmosphere, which dilutes the maize pollen plume with more clean air. This study compares maize hourly concentrations and ground level flux levels inside and outside a virtual maize flux in the presence and absence of operating wind turbines. Results from a 14-day simulation of maize transport xii with and without operating wind turbines indicate that each difference of corresponding concentration and flux levels is statistically significant. Likewise, patterns of maize pollen transport inside the farm with turbine effects are significantly different from those without turbine effects. Overall, the average maize pollen concentration inside the farm in the absence of turbine effects is about 5 times greater than the corresponding maize pollen concentration with turbine effects. The total mass of maize pollen released into the air is the same whether the wind turbines are present or not. The portion of maize pollen staying inside the farm, on the other hand, is influenced by turbulence. For instance, the increased surface roughness caused by the turbine effects will increase the mechanical turbulence. Because the high mechanical turbulence carries a large portion of maize pollen away from the farm, only a small portion of maize pollen stays inside the farm due to the high turbulence that lifts maize pollen into higher levels of flow where the wind speed is stronger. In contrast, without turbine effects, a small portion of maize pollen leaves the farm while most of it deposits on the ground much sooner than it would with turbine effects. Therefore, maize pollen concentration and ground level flux in the presence of turbine effects will be greater than they are without turbine effects at a relatively far distance from the farm.
PH.D in Environmental Engineering, December 2012
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Title: RESILIENT CITIES OF THE FUTURE UTILIZING NATURAL INTELLIGENCE TO RETROFIT THE URBAN SYSTEMS
Creator: Naik, Vaidehi
Date: 2017, 2017-07
Description: Accentuated by the industrial revolution, the climate change is aging our cities, which are now facing an ecological, economical, and...
Show moreAccentuated by the industrial revolution, the climate change is aging our cities, which are now facing an ecological, economical, and political imbalance resulting into the degraded quality of urban living. Not only has global warming altered the earth’s natural patterns, but it also altered the economic and socio-cultural urban patterns. With the growing needs of rapidly expanding urban population due to the industrial revolution, the cities underwent unplanned sprawling of urban agglomerations. However, our globalized economic system has evolved the way we live, work, and play, transforming the modern infrastructure growth models significantly. Our architects, urban planners, and policy makers are powered by the environmental scientist’s years of research and analysis, yet are struggling to replenish the post-industrial age rust belt mayhem with sustainable solutions. As the transition from industrial to ecological age become eminent, by investigating into the natural intelligence’s survival techniques, we could extract practical solutions to using clean and renewable energy systems to support life. This thesis aims at analyzing the current trends in redesigning and retrofitting the urban-systems with the eco-systems at the micro- and macro- scales, thus providing with sustainable solutions to the new city center of the sixth largest town in Canada, Mississauga. Caused by rapid urbanization, population growth & migration, increased emission of green house gases, and overuse & pollution, our deteriorating infrastructure is grappling for mitigation against climate change, and global warming. Using natural intelligence to shift from linear to a closed loop system, the solutions provided herein aims at increasing the infrastructure’s resource efficiency and changing from fossil fuel to solar economy. Catalyzed by the proposed Midwestern high-speed rail line, the project in Mississauga (Ontario, Canada) seeks to introduce the hybrid, mixed-use, transit oriented development to instigate the shift towards eco-cities. These intermodal transit infrastructure aims to bring a strategically sustainable change at a neighborhood scale, thus eventually refurbishing the entire city, one territory at a time. The idea of these utopian cities may seem unachievable at a larger scale, but the cities like Hammarby Sjöstad, Tianjin, and Dongtan seem to lead, inspire, and equip the ignorant with their sustainable approach to growth. By transitioning towards an ecological age, there seems a way to negating the effects of human induced climate change, and make our planet sustainable for the future generations to survive.
M.S. in Architecture, July 2017
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Title: LAND USE EFFECTS ON WATER QUALITY: BUILDING A FRAMEWORK FOR CHICAGO RIVER WATERSHED
Creator: Mahdi, Naila Ghidey Ismail
Date: 2012-05-09, 2012-05
Description: The purpose of this study is to introduce a framework that enables a holistic watershed approach that models the dynamics of water quality and...
Show moreThe purpose of this study is to introduce a framework that enables a holistic watershed approach that models the dynamics of water quality and landuse in a highly urbanized watershed. The landuse-water quality relationship is a complex relationship and has not been adequately addressed for highly urbanized watersheds. Factors such as inadequate urban planning, increase of impervious areas and dynamics of population growth are some of the reasons for the complex relationship. Also point sources are always easy to be identified and controlled unlike nonpoint sources such as urban storm runoff. Both quantities and transport pathways of pollutant inputs are impacted by land use in the watershed. So, examining the factors that govern the relationship between different land uses and water quality within a watershed can give insights and important information about existing and potential sources of contamination. The two backbone concepts in this study are the holistic watershed perspective and the role of historical data records as part of assessment, modeling and integration tools of the watershed framework. Analysis of the records will explain watershed conditions identifying the major problem areas and justify the modeling and post analysis procedures. Data sources are often important but data availability, heterogeneity and conformity are the main challenges in integrating these sources. This research presents an approach to integrate the watershed data in a single repository and methodologies for analyzing and assessing the watershed using data warehouse and data mining technologies. A multi-dimensional model that supports complex querying of watershed data and discovery of trends and patterns in data by incorporating 40 years worth of watershed data from different source agencies in a central repository is introduced. Also, the discipline of data driven modeling was introduced in this thesis using the developed central repository. Several regression and classification algorithms were presented and assessed for their appropriateness for predicting total nitrates using few watershed attributes. The results show acceptable prediction accuracy. Five years of water quality simulation using the multi-purpose environmental analysis system BASINS coupled with the comprehensive, conceptual, and continuous simulation watershed scale model HSPF resulted in export coefficients for level (III), detailed land use for the Chicago River watershed. The water quality simulation approach utilized in this research to generate the coefficients constitutes a new contribution to the Chicago River watershed and other highly urbanized watersheds. The continuous calibrated and validated model can be used in the investigation and analysis of different scenarios and possible future conditions, thus providing a planning tool for regulatory environmental agencies. The data driven models developed can be used as operation tool to maintain the water quality parameters especially if TMDL and WQS are developed for Chicago River Watershed. So the framework proposed for this study can be considered robust with the proposed integration, planning and operating techniques and tools. Furthermore, an optimization tool is introduced in the future work section.
Ph.D. in Environmental Engineering, May 2012
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Title: AN OVERVIEW OF INSPECTION, REHABILITATION AND MONITORING METHODS USED FOR CHICAGO’S MOVABLE BRIDGES
Creator: Jalabert, Patrick C.
Date: 2012-07-09, 2012-07
Description: Chicago is the historical birthplace of movable bridges. Earlier than any other city in the world, this Midwestern city started developing...
Show moreChicago is the historical birthplace of movable bridges. Earlier than any other city in the world, this Midwestern city started developing solutions to obstacles facing river transportation through innovations in moveable bridge design. With over forty movable bridges built, today, the city faces a major rehabilitation issue with the deterioration of these bridges. The need to assess the condition, and plan for the future sustainability of these bridges, is vital to Chicago’s economy and to the safety of thousands of people who cross the Chicago River every day. As many other cities in the world face problems with their moveable bridges, any plan by pertinent agencies to rehabilitate bridges in Chicago is expected to set standards for the rehabilitation and maintenance of moveable bridges. An overview of guidelines set forth by the American Association of State Highway and Transportation Officials (AASHTO) and procedures and/or methods adopted by local authorities to inspect, repair and reconstruct moveable bridges in Chicago, are important steps in identifying the underlying issues related to the structural condition and degradation process of the many movable bridges still in operation in Chicago. The objective of this study is to review (1) current practices for movable bridge inspection, repair and rehabilitation; and (2) actual repairs projects, conducted under the authority of the Chicago Department of Transportation’s Division of Engineering, to identify and summarize the underlying structural and/or serviceability issues that are inherent to movable bridges in Chicago. Specifically, the study is expected to highlight a number of important issues that stem from age, repeated use and factors that have caused deterioration of Chicago’s movable bridges and the type of repairs that may be needed to guarantee the future safe operation of these bridges.
M.S. in Civil Engineering, July 2012
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Title: AN INVESTIGATION INTO THE SIGNIFICANCE OF LENGTH-THICKNESS RATIO IN GUSSET PLATE BEHAVIOR IN BRIDGE TRUSSES
Creator: Olechno, Patrick
Date: 2012-07-12, 2012-07
Description: n/a
M.S. in Civil Engineering, July 2012

$THE CHARACTERIZATION FOR B2 STRUCTURE AND L2\ STRUCTURE IN THE AG-MG AND AG-MG-IN SYSTEM$

Title: THE CHARACTERIZATION FOR B2 STRUCTURE AND L2\ STRUCTURE IN THE AG-MG AND AG-MG-IN SYSTEM
Creator: Kim, Do Hyung
Date: 2013, 2013-05
Description: The concentration of point defects and the long range order for ordered B2 AgMg alloys, quenched from 973K, was investigated by statistical...
Show moreThe concentration of point defects and the long range order for ordered B2 AgMg alloys, quenched from 973K, was investigated by statistical thermodynamic modeling, powder X-Ray Diffractometery and diffraction simulation as a function of composition. The lattice parameter behavior on the Ag rich side are expectably having constitutional and thermal anti-site defects on both Ag and Mg sub-lattices, corresponding to the literature data. On the other hand, the Mg rich side has substantially thermal vacancy defects based on the lattice parameter data which shows lower, compared with previously reported data. Concentration of the equilibrium point defects at 973K was calculated from two thermodynamic models, where the Ag rich side was based on the constitutional and thermal anti-site defect formation and the Mg rich side was based on the hybrid defect formation consisting of vacancy, Mg and Ag anti-site defects The experimental long range order at 973K, determined from the integrated intensity ratio of (100) super-lattice reflection to (200) fundamental reflection, is in quite good agreement with the theoretical long range order at 973K based on the calculated integral intensities from the diffraction simulation with the equilibrium concentration of each point defect, obtained by two thermodynamic models. Furthermore, point defect hardening coefficients on both sides of stoichiometry were determined by the measurement of the Vickers hardness as a function of the equilibrium concentration of the main point defects deduced from two thermodynamic models. The hardening coefficient is G/16 for the Ag rich side with respect to Ag anti-site defects and G/3.1 for the Mg rich side with respect to vacancy defects. Also, two hardening coefficients are corresponding to the empirical correlation for the several binary B2 intermetallic compounds with anti-site defects (G/9 to G/85) xvi and vacancy defects (G/3 to G/4). This suggests that the elastic size effect on the Ag rich side is the primary hardening mechanism due to constitutional and thermal Ag anti-site defects while the Mg rich side is likely to have the elastic modulus effect due to constitutional and thermal vacancy defects. It is also indicated that the vacancy defect is more significant hardener than Ag anti-site defects for the ordered B2 AgMg intermetallic system. The partial liquidus projection in the Ag-Mg-In ternary system was established by the primary phase and liquidus temperature, using the Scanning Electron Microscopy, Energy Dispersive Spectroscopy and Differential Scanning Calorimetry. The results showed that the AgMg1-xInx phase of the Ag-Mg-In ternary system has a large primary solidification field up to 90 at.% of In, so that most ternary invariant reactions of the In rich field must be formed beyond 90 at.% of In. The liquid-solid schematic reactions in the Ag rich field were experimentally confirmed, but those of the In rich side have not been established. Furthermore, the ordering phase transition and melting temperature of the Heusler phase AgMg1-xInx alloys were investigated using Differential Scanning Calorimetry, Scanning Electron Microscopy, and powder X-Ray Diffractometery. The DSC results indicated that the melting temperature decreased with increasing the In composition, but a thermal peak for the ordering phase transition was not detected due to either a very small heat of transition or a second order transformation. The XRD results showed that the L21 structure of the Heusler phase was observed for the 15 at.% of In alloy and the degree of order of L21 structure continuously increased with the In composition, resulting from the (111) super-lattice intensity with respect to the In composition. The L21 structure ordering of the 15 at.% of In and 20 at.% of In system xvii was gradually decreased with increasing the annealing temperature, corresponding to decreasing the (111) super-lattice intensity and the long rang order parameters of the L21 structure. These XRD behaviors suggest that the L21/B2 ordering transformation phenomena is a second order transformation with respect to temperature.
PH.D in Material Science and Engineering, May 2013
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Title: GENERAL FACTORS IN EMPLOYEE ENGAGMENT SURVEYS
Creator: Mcdonald, Jordan C.
Date: 2017, 2017-07
Description: There is growing recognition of the need to model general factors within the context of job attitude constructs and their effects in the...
Show moreThere is growing recognition of the need to model general factors within the context of job attitude constructs and their effects in the interpretation of employee engagement survey data. General factors are defined as latent variables that account for a substantial proportion of variance in multidimensional constructs and influence all subsets of items (Ree, Carretta & Teachout, 2015). The bifactor model has gained increased attention for its advantages in modeling multidimensional constructs, including improved fit and enabling the examination of the unique contributions of the general and specific factors for prediction (Chen, Hayes, Carver, Laurenceau, & Zhang, 2012; McAbee, Oswald, & Connelly, 2014; Gignac, 2016; Reise, 2012). The aim of the current study was to apply the advantages of the bifactor model in the employee engagement survey context in predicting employee turnover compared to alternative factor models (i.e., correlated factors model). The current research consisted of two studies: the first was conducted to determine the factor model that balanced parsimony and plausibility by cross-validating the model’s generalizability with a different set of data sharing the same survey items. The second study compared the factors of the bifactor model—including the general factor—and the factors of the correlated factors model in predicting employee turnover. Accounting for the general factor in employee engagement surveys resulted in different factors being significantly to turnover compared to when the general factor was not modeled. Practical implications and directions for future research are discussed.
M.S. in Psychology, July 2017
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Title: INVESTIGATION OF BI-IN-SN AND BI-IN-SN-GA AS PHASE CHANGE MATERIALS
Creator: Huynh, Hong Trang
Date: 2012-05-02, 2012-07
Description: Phase change energy storage is one of the most effective ways to store thermal energy. The difference between metallic phase change materials ...
Show morePhase change energy storage is one of the most effective ways to store thermal energy. The difference between metallic phase change materials (PCMs) and organic and inorganic PCMs is discussed. Bi-In-Sn and Bi-In-Sn-Ga alloys with near eutectic compositions were analyzed using DSC, X-Ray, EDS and metallography to establish the alloy properties. An attempt was made to package the alloy in metallic and non-metallic foams and various tests such as infiltration and cycling tests were conducted to test the feasibility of various containment materials. These PCM alloys were applied in a prototype cooling system of electronic devices for better heat dissipation than conventional heat sinks. Tests were conducted to measure the effectiveness of the alloys. Different designs were suggested for the containment of the alloy.
M.S. in Mechanical, Materials, and Aerospace Engineering, July 2012
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Title: Computational Techniques for Wind Turbine Power Prediction
Creator: Goyal, Udit
Date: 2011-11-28, 2011-12
Description: Wind energy is expected to play an important role in meeting the ever- increasing energy requirements and reducing our dependence on...
Show moreWind energy is expected to play an important role in meeting the ever- increasing energy requirements and reducing our dependence on conventional sources of energy. Wind turbines are broadly classfied as horizontal-axis and vertical-axis depending upon the orientation of the rotor shaft relative to the wind direction. Considerable research has been carried out on horizontal-axis wind turbines, which today are sophisticated and efficient electro-mechanical systems. Continuous research and development in areas of electronics, controls and instrumentation aids in the advancements of this technology. From an aerodynamic point of view the Betz limit is known to impose theoretical limit on the power extraction of propellers. The momentum balance equations show that the maximum of 59.3 percent of free-stream energy can be extracted by propellers. This limit, however is not well de fined, particularly when considering diff user and nozzle-augmented wind turbines with local flow accelerations. In this study the actuator disk approach is used to model the momentum loss across a wind turbine rotor and simulate the Betz limit using Fluent software. This approach is subsequently applied to study the coefficient of performance expected from dif user and nozzle-augmented wind turbines. Vertical-axis wind turbines, on the other hand, are still not completely understood in terms of blade aerodynamics and are the focus of various research studies. Large variations in angle of attack and wake evolution downstream of the blade have a time-dependent e ffect on the blade forces, instantaneous torque and hence the coefficient of power of the turbine. Since Navier-Stokes solutions for vertical- axis wind turbines are expensive and complicated, various low-cost models have been developed based on momentum balance such as single, double and double multiple- streamtube formulations. These models, however, use static lift and drag data for the airfoils as inputs, neglecting the unsteady e ffects on aerodynamic coefficients. In the present study, an alternative approach based on the panel method is explored further for developing a low-cost computational method for simulating the aerodynamics of vertical-axis wind turbines. At each time step an airfoil is represented as a combination of source and vortex distributions which induce a potential in the flow fi eld. A time-stepping mechanism is implemented satisfying the Kutta and the Kelvin Helmholtz condition for the wake evolution behind the rotating blades. The e ffect of this vortex evolution on the aerodynamic forces on the airfoil is studied, focusing on the coefficient of performance (Cp) of the blade. Results show a decrease in Cp values till the wake attains a quasi steady state. A comparison study is performed with other computational models, showing the importance of the wake evolution in time. An optimization of the blade pitch angle is also performed by defi ning a composite variable pitch function in order to improve the torque and hence the instantaneous power from the blades.
M.S. in Mechanical and Aerospace Engineering, December 2011
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Title: CHICAGO’S REFORMATIVE URBAN ARMATURES HYPERACTIVE INFRASTRUCTURAL LINKAGES
Creator: Osborne, Zachary C.
Date: 2015, 2015-12
Description: This research will project the impact of a new urban armature of logistics for the city of Chicago capable of improving the movement and...
Show moreThis research will project the impact of a new urban armature of logistics for the city of Chicago capable of improving the movement and experiences of people and goods throughout new hyperactive urban developments. Through the use of historical and contemporary precedence this new urban plan will address the continual shift in public domains, creating improved linkages and socially charged urban environments. As the inevitable densification of Chicago occurs a new network of connective infrastructure is required for creating new dynamic, three-dimensional public realms. The demand for such kinetic building models is caused by the mass influx of the creative-class returning to urban centers for both work and living. Consisting of a highly diverse set of programs, these new models for Chicago's west loop business district will focus on reconnecting the public to undiscovered urban layers. These hybrid developments break the mold of Chicago's modernist high rise tower allowing for mixing and overlapping of building programs, bringing strangers together in impromptu gathering spaces. Tiered circulation networks serve as the key infrastructural element facilitating these new socially engaging environments. Through the use of this tiered system primary circulation elements allow for the direct movements of private users and services while secondary and tertiary systems allows for pedestrians to penetrate "private" space fostering the interactions amongst a diverse a group of people. Within the new west loop district, the principles applied in creating vibrant urban atmospheres must be applied to internalized building programs, offering a variety of destination points throughout. Through the shaping of space by both generic and specific building forms the spaces in between become critical for the mixing of various characters. New urban armatures must be applied within these spaces providing the support for versatile and adaptable building programs and public spaces.
M.S. in Architecture, December 2015
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