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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: TEXT MESSAGE REMINDERS AND TREATMENT ADHERENCE IN A TYPE II DIABETES POPULATION: A FEASIBILITY STUDY
Creator: Kramer, Alexis J.
Date: 2014, 2014-05
Description: Type II Diabetes (T2DM) is a chronic disease effecting millions of people worldwide. It is well documented that lifestyle changes including...
Show moreType II Diabetes (T2DM) is a chronic disease effecting millions of people worldwide. It is well documented that lifestyle changes including adherence to treatment regimens (e.g. glucose monitoring) can be very effective in reducing the onset and progression of T2DM. The literature suggests that individuals within this population are often non-compliant with treatment recommendations, for a variety of reasons (e.g. psychological factors, availability of resources, co-morbid conditions). The purpose of this study was to investigate the suitability, recruitment and retention feasibility, and preliminary outcomes of a text message reminder system on treatment adherence within a type 2 diabetic population, as measured by blood glucose levels (HbA1c). A total of 28 participants were randomized into experimental or no-treatment conditions. Participants in the experimental group received text message reminders on either a fixed or variable schedule; with either neutral or calming test message content. They also completed a qualitative feedback measure, to assess participant satisfaction with the proposed intervention. Participants in the no-treatment condition did not receive any text message reminders. All participants completed the Diabetes Care Profile (DCP) and Short Form-36 Health Form Survey, Version 2 (SF-36v2) at baseline and three months later (time 2). Preliminary analyses show that frequency of text message reminder significantly impacted glucose levels over time. The content of the text message was not shown to have a significant effect on glucose levels. Participant perception of the proposed intervention was mixed. Despite diverse recruitment efforts, recruitment was low, however, retention was high.
PH.D in Psychology, May 2014
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Title: AN INVESTIGATION INTO FIRE ENDURANCE OF WOOD AS A STRUCTURAL MATERIAL IN TALL BUILDINGS
Creator: Ling, Lei
Date: 2014, 2014-05
Description: With the global growth in using timber as a structural material for tall buildings to respond to the trend of sustainability, several timber...
Show moreWith the global growth in using timber as a structural material for tall buildings to respond to the trend of sustainability, several timber buildings from 7 stories to 10 stories have already been built in Europe and Australia. However, in the United States, timber buildings are still limited to 6 or less stories [2]. The motivation of this thesis is to respond to the proposal for fire safety challenges of tall wood buildings issued by the Fire Protection Research Foundation. Since using timber as a structural material is just underway, more related studies from different academic departments and organizations are required in order to characterize the fire performance of tall timber structures, investigate the related challenges and necessary research to achieve a high level of safety and property protection equal to those offered by concrete or steel structures, and promote the development of this type of building systems. This thesis presents a literature review of global design cases of timber buildings, corresponding calculations of fire-resistance rating, recent and ongoing fire tests, and adhesive effects of timber members. A gap analysis was developed, with current challenges of building timber buildings presented, focusing on structural design, fire protection, durability, and code regulations requirements. This gap analysis was then compared with other similar published papers in an attempt to have a better understanding of what areas of research are needed, and suggesting for further studies to promote the idea of using timber as a structural material for tall buildings.
M.S. in Civil Engineering, May 2014
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Title: BLADE PITCH OPTIMIZATION METHODS FOR VERTICAL-AXIS WIND TURBINES
Creator: Kozak, Peter
Date: 2016, 2016-07
Description: Vertical-axis wind turbines (VAWTs) offer an inherently simpler design than horizontal-axis machines, while their lower blade speed mitigates...
Show moreVertical-axis wind turbines (VAWTs) offer an inherently simpler design than horizontal-axis machines, while their lower blade speed mitigates safety and noise concerns, potentially allowing for installation closer to populated and ecologically sensitive areas. While VAWTs do offer significant operational advantages, develop- ment has been hampered by the difficulty of modeling the aerodynamics involved, further complicated by their rotating geometry. This thesis presents results from a simulation of a baseline VAWT computed using Star-CCM+, a commercial nite volume (FVM) code. 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. Several optimization techniques have been developed for the adjustment of blade pitch based on finite-volume simulations and streamtube models. The effectiveness of the optimization procedure is evaluated and the basic architecture for a feedback control system is proposed. Implementation of variable blade pitch is shown to increase a baseline turbine's power output between 40%-100%, depending on the optimization technique, improving the turbine's competitiveness when compared with a commercially-available horizontal-axis turbine.
Ph.D. in Aerospace and Mechanical Engineering, July 2016
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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: STUDIES ON CONNECTIVE AND NEUROLOGICAL TISSUES IN RELATION TO DISEASE
Creator: Madhurapantula, Rama Sashank
Date: 2015, 2015-12
Description: The structure of connective tissue is of great importance for homeostasis of the cells present within it. Pathologies leading to changes in...
Show moreThe structure of connective tissue is of great importance for homeostasis of the cells present within it. Pathologies leading to changes in the structure of the extracellular matrix (ECM), in particular collagen have been shown to play a pivotal role in the progression of various diseases. Similarly, changes in the structure of specific elements in neurological tissues, such as myelin, have been shown to elicit adverse responses to injury. This thesis explores two main aspects: 1) the structural changes brought about by high sugar concentrations, much similar to that found in diabetic patients, to the structure of type I collagen and 2) possible effects of traumatic brain injury (TBI) to the structure of neurons in rat brains. Specific changes in the structure and packing of collagens in various tissues could be potential therapeutic targets to control the progression of related diseases. However, the information available on the nature, specificity and the relevance of these changes at a molecular level are largely unknown and have been explored only sparsely. The result of non-enzymatic glycosylation i.e. glycation, is the formation of sugar- mediated crosslinks within the native structure of type I collagen. The chemistry behind these crosslinks, also known as Advanced Glycation Endproducts (AGEs), has been known for decades. However, the exact locations or regions of high propensity for the formation of these crosslinks within the packing structure of collagen are largely unknown. The results presented in this thesis inform on the location of possible crosslinks using the principle of Multiple Isomorphic Replacement (MIR) to and correlate the effects of crosslinks to the structural and functional sites present on the D-periodic arrangement of collagen into fibrils. An extension to this is the study of the effects of povidone-iodine on the packing structure of collagen. Iodine is used as a common disinfectant in surgery and first aid. Prolonged treatment with iodine is detrimental to the structure of collagen underlying the wound site (surgical or otherwise). This is particularly important in large surface area wounds, as seen in open-heart, hip and joint replacement surgeries and amputations. Diabetic patients are more prone to injuries to limb extremities and a common procedure to stop infections from spreading to the rest of the body is amputation of the limb and constant treatment with low doses of iodine immediately following surgery for a certain length of time. The results presented in this thesis demonstrate specific disintegration of collagen fibrils in rat tail tendons, from a short iodine treatment. This is detrimental for cellular activity, more so in processes like wound healing. TBI results in the loss of neurological control and/or function of various parts of the body, governed by this region. The results presented herein, inform and support the finding that neuroplasticity, in the hemisphere opposite to that where injury was delivered, compensates for the functional deficits as a result of TBI. The data presented here can be used in developing rehabilitation regimens for TBI patients on case-to-case basis to restore most of the functional deficits observed thereof, and also as a factor of predicting the onset of secondary neurological disorders (for instance amyloid related pathologies) at a later stage in life.
Ph.D. in Biology, December 2015
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Title: HOUSING PUBLIC TRANSPORTATION WITHIN A SOCIAL CONDENSER
Creator: Loman, Catherine
Date: 2016, 2016-12
Description: Throughout the United States and Canada the railroad, a system that was once the central method of transportation through the countries, has...
Show moreThroughout the United States and Canada the railroad, a system that was once the central method of transportation through the countries, has had a large downfall in the popularity and development after the introduction of the car into the city and the surrounding area. With the downfall of the train came the downfall of the use of the train station, a space that was once a local temple of the city has now become an economic center with no larger connection to the city. If a new high-speed rail system is to be introduced into North America then there is the need for a new method of looking at what the train station can be and how it can interact with the larger city around it. With an in-depth study of the city that the station is located in the local nature of the city will become prevalent and play a key role in the conceptual design of the station and how it can create a stronger social presence within the city and within the line.
M.S. in Architecture, December 2016
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Title: INTERPRETATION OF ADAPTIVE REUSE ISSUES IN MULTIPLE SCALES, BUILDING, NEIGHBORHOOD, CITY
Creator: Loukas, Panagiota
Date: 2015, 2015-12
Description: The purpose of this study is to interpret the topic of adaptive reuse, focusing on the reuse of existing buildings and new structures inserted...
Show moreThe purpose of this study is to interpret the topic of adaptive reuse, focusing on the reuse of existing buildings and new structures inserted into them. The issues related with adaptive reuse are not a new field in architecture but is related to previous practices such as preservation and conservation. Focusing on the issue of adaptive reuse in order for existing structures to cover the new needs of an emerging society, giving a new use. Other disciplines, such as social and political are forming and guiding those decisions. The topic of what to keep and what to discard is global and various solutions has been given in the past years, focusing on monuments and landmarks conservation, preservation or practices of adaptation in the cities history. The research analysis in various scales, engaging the site to its surrounding, through neighborhood analysis and its urban context are important. Understanding the problem means focusing the research not only on the aspect of architecture agenda since there are political and social practices engaging with the transformation. It means focusing on the issue of adaptive reuse as an important cultural topic related with social, political and economic factors.
M.S. in Architecture, December 2015
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Title: Sex and Architecture
Creator: Nekkanti, Hashika C.
Date: 2023
Description: This thesis delves into the fascinating and intricate connection between sexual behaviour and architecture, offering a comprehensive...
Show moreThis thesis delves into the fascinating and intricate connection between sexual behaviour and architecture, offering a comprehensive exploration of the multifaceted factors that shape human sexuality within the context of built environments. The research is divided into six chapters, each providing a distinct perspective on the complex relationship between sexuality and the spaces we inhabit. Chapter 1 serves as an introduction, setting the stage for the study and highlighting the importance of understanding how architectural design and spatial arrangements can influence and be influenced by human sexual behaviours. Chapter 2, "Milieu and Sexed Bodies," delves into the impact of environmental stimuli on sexual arousal. By examining how architectural elements, aesthetics, and spatial configurations can elicit eroticism and arousal, this chapter sheds light on the subtle ways in which built environments interact with our intimate desires. Furthermore, it delves into the psychological aspects of fetishism and voyeurism, exploring how these sexual behaviours find expression within architectural settings. Chapter 3, titled "Sexual Behaviour," delves into the profound influence of history on human sexuality. It examines how cultural norms, religious beliefs, and social backgrounds have shaped and continue to shape sexual attitudes and behaviours across different societies and time periods. The chapter also explores the concept of polymorphous behaviour, emphasizing how architecture can create spaces that cater to diverse expressions of human sexuality. Additionally, it investigates the impact of queer spaces, highlighting the significance of inclusive design in fostering a sense of belonging and acceptance for individuals with diverse sexual identities. Chapter 4 turns its attention to "Mediated Sexuality," offering a historical analysis of how various forms of media have played a pivotal role in shaping sexual attitudes and behaviours. From ancient art to contemporary pornography, this chapter explores how media representations have influenced perceptions of sexuality, and it examines the emergence of pornomodernism, a cultural phenomenon impacting both media and architectural expressions of eroticism. Moreover, it investigates how architecture has incorporated and responded to the eroticized spaces depicted in media. Chapter 5 focuses on the "Coital Environment," a fascinating aspect of architecture that intertwines with sexual behaviour. This chapter delves into the realm of sex tourism, examining how certain destinations and spaces have become associated with sexual encounters. It analyses the design and function of dedicated places for sex within architectural contexts, providing insights into the factors that influence the creation and acceptance of such spaces in different societies. Finally, Chapter 6 presents a comprehensive "Conclusion," synthesizing the key findings from the preceding chapters. It emphasizes the critical role that architecture plays in shaping human sexual behaviours and highlights the social and cultural implications of design decisions in built environments. The chapter concludes with reflections on the significance of creating inclusive and supportive spaces that celebrate and embrace diverse sexual identities and experiences, paving the way for more empathetic and human-centric architectural design in the future. In conclusion, this thesis offers a profound exploration of sexual behaviour and architecture, shedding light on the intricate interplay of environmental stimuli, historical influences, and mediated sexuality in shaping our intimate experiences within the spaces we inhabit. It serves as a valuable resource for architects, urban planners, social scientists, and anyone interested in creating environments that foster a positive and inclusive approach to human sexuality.
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Title: CHEMISTRY OF BUCKYBOWL FROM CLOSED-SHELL TO OPEN-SHELL
Creator: Li, Jingbai
Date: 2019
Description: Buckybowl is an open geodesic polyaromatic molecule with unevenly distributed π-electron on its convex and concave surface, which leads to a...
Show moreBuckybowl is an open geodesic polyaromatic molecule with unevenly distributed π-electron on its convex and concave surface, which leads to a readily accessible π-surface for substitution reactions and complexation with various metals. Despite the diverse structures of buckybowl complexes observed in the previous experimental study, our computational work has shown that the π-surface of buckybowl always plays the most important role in the bonding. Modification of the π-surface by changing the size of conjugation and the curvature enable us to tune the bonding preference of the buckybowl surface and the stability of the complex. Our continued study has shown similar importance of the π-surface in functionalization of buckybowl with different electrophilic groups. Surprisingly, our investigation on buckybowl cations intrigued an original perspective of aromatic behavior of the π-surface. Our results have revealed an intrinsic nature of aromatic stabilization in polyaromatic cations, which is mainly attributed to the depletion of anti-aromaticity at the center ring. Further study showed an explicit correlation between the curvature of π-surface and the stability of adducts, aromatic behavior at center ring, as well as the spin distribution over polyaromatic moiety. By curving the π-surface, we have proposed several buckybowl radical adducts and confirmed their stability. These models provide an alternative strategy of developing polyaromatic spin carriers, which have a great potential in the manufacture of quantum bits. We believe our comprehensive theoretical study on versatile chemistry of buckybowl and related polyaromatic hydrocarbons can offer fundamental understanding and essential guidance for developing buckybowl-based electrode materials in the lithium-ion battery, organometallic building block, and spin electronic devices.
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Title: A Limited Case Study: Perspectives of Students, High School Teachers, and College Instructors About Advanced Placement Mathematics Courses
Creator: Joseph, DeJuana V.
Date: 2023
Description: ABSTRACTBackground. The underrepresentation of Black and Latinx students in STEM is highlighted due to structural impediments. Although AP...
Show moreABSTRACTBackground. The underrepresentation of Black and Latinx students in STEM is highlighted due to structural impediments. Although AP mathematics classes are being introduced as a solution, students from underprivileged schools continue to confront challenges. The study project seeks to investigate the obstacles associated with teaching AP mathematics courses in disadvantaged high schools and to gather perspectives from various stakeholders.Methodology. The study employs qualitative one-on-one interviews and an interpretive research paradigm. The sample comprises mathematics faculty, first-year college students, high school AP math teachers, and one high school student. Thematic analysis is used and ethical considerations are taken into account. Limitations include time and resource constraints, a small sample size, and potential inconsistencies in participant responses.Results and Findings. AP mathematics classes may inspire students to continue STEM in college, yet obstacles such as time constraints and knowledge gaps exist. Students' employment choices are influenced by their own interests and abilities. High school math teachers and college professors highlight algebraic skills as crucial for success in college mathematics, particularly in calculus classes.Discussion. The STEM enrollment problem does not only affect minority students; AP math can be a pathway for all kids. Improving AP math readiness for all students is critical for addressing the STEM professional shortage. It is essential to use extra measures to increase student interest in STEM. Strong foundational algebraic knowledge is required for success in higher education, necessitating stakeholders to focus on improving STEM enrollment and completion rates.
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Title: Ground Monitors to Support Navigation Operations of ARAIM and GBAS
Creator: Patel, Jaymin Harshadkumar
Date: 2023
Description: Receiver Autonomous Integrity Monitoring (RAIM) currently provides safehorizontal navigation guidance to en route civil aircraft using the GPS...
Show moreReceiver Autonomous Integrity Monitoring (RAIM) currently provides safehorizontal navigation guidance to en route civil aircraft using the GPS L1 frequency. As an evolution of RAIM, Advanced RAIM (ARAIM) is being developed to provide vertical guidance in addition to horizontal using multiple constellations and dual frequency thus facilitating precision approach without ground support for civil aircraft. However, navigation guidance during zero-visibility (Category III) precision landing requires an additional support in real time from a Ground Based Augmentation System (GBAS). To improve the aircraft navigation solution, GBAS broadcasts a differential correction and monitors any failure on transmitted satellite signals. This dissertation contributes to ARAIM and GBAS to improve existing navigation operations in order to enable precision approach and landing.The achievable performance of ARAIM is highly dependent on the assumptionson a constellation’s nominal Signal-In-Space (SIS) error models and a priori fault probability. In the framework of ARAIM, an Integrity Support Message (ISM) is envisioned to carry the required SIS error-model parameters and fault statistics for users. The ISM is generated and validated through offline monitoring, and disseminated along the navigation message. The first dissertation contribution is to provide necessary satellite positions and clock biases as a truth product to evaluate nominal SIS range errors (SISREs). An estimator is developed to generate accurate ephemeris parameters to provide these truth products. The estimator’s performance is demonstrated for the Global Positioning System (GPS) constellation by utilizing the International GNSS Service (IGS) ground network to collect dual-frequency raw GPS code and carrier phase measurements. The resulting SISREs from the estimator are predicted to have a standard deviation of 0.5 m. When estimated ephemeris parameters and clock biases are compared with precise IGS orbit and clock products, the resulting SISREs are within ±2! at all times. In the second contribution, a new approach is proposed to generate the ISM by modeling the ephemeris parameter errors directly. In preliminary analysis, an ephemeris parameter error model is developed for the broadcast GPS legacy navigation message (LNAV) under nominal conditions. Then, the proposed approach is demonstrated to provide the nominal bias and standard deviation on GPS SISREs.As a part of fault monitoring in the GBAS, a ground monitor is developedto detect ephemeris failures, incorrect broadcast satellite positions, and hazardous ionosphere storms using either single- or dual frequency. The monitor also addresses the challenge of fault-free differential correction when satellites are rising, newly acquired, and re-acquired. The monitor utilizes differential code and carrier phase measurements across multiple reference receiver antennas as the basis for detection. Finally, the analytical performance of the monitor is demonstrated to meet Category III precision approach and landing requirements.
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Title: Operation Kosovo (Summer 2003) IPRO 397
Date: 2003, 2003-07
Description: This IPRO team will have the responsibility of extending Operation Kosovo. Operation Kosovo is an IIT-Chicago Kent initiative to promote rule...
Show moreThis IPRO team will have the responsibility of extending Operation Kosovo. Operation Kosovo is an IIT-Chicago Kent initiative to promote rule of law, democracy, civil society, and economic development in Kosovo. Students will continue work on projects such as: providing research assistance to legal counsel in Kosovo through CDRC; providing support to the University of Pristina law school's student organization; establishing a Kosovo Leadership Council, a Small Business Assistance Clinic, and a Kosovo investment fund; establishing firm contact with Kosovars in the Diaspora; maintaining support for the University of Pristina law school's externship program; website updating; and posting Kosovar law on the internet. There may also be an opportunity to structure a process for developing business plans for new enterprises in Kosovo as the team's work moves forward. Students who join this team will have the opportunity to make a positive and lasting contribution to the people of Kosovo; and will develop a deep appreciation for how social, political, technology and economic factors combine to influence rule of law.
Sponsorship: Criminal Defense Resources Council (CDRC)
Project Plan for IPRO 397: Operation Kosovo for the Summer 2003 semester
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Title: WETTING OF FUEL CELL MATERIALS BY MOLTEN CARBONATE: OBSERVATION OF SPREADING AND PENETRATION
Creator: Gao, Liangjuan
Date: 2018, 2018-05
Description: The molten carbonate fuel cell (MCFC) continues to attract significant attention due to its high performance over a lifetime of three to five...
Show moreThe molten carbonate fuel cell (MCFC) continues to attract significant attention due to its high performance over a lifetime of three to five years. The wetting of fuel cell materials by the molten carbonate is key to the long-term performance. Therefore, the wetting behavior under MCFC operating conditions was studied by means of the sessile drop method using a digitized optical analysis system. Specifically the spreading of molten carbonate on dense and porous materials was determined, as well as the penetration into porous materials. Observations were made of the melting and spreading of a solid carbonate pellet upon controlled temperature increase, placed on top of the dense or porous substrate, under either a reducing atmosphere (80%H2+20%CO2 humidified at 45oC), pure CO2 atmosphere, or oxidizing atmosphere (1%O2+99%N2). To provide a relatively simple base case, an extensive study of wetting of dense Ni foil was made. It was demonstrated that the water-gas shift reaction occurred at the interface of the Ni surface and molten carbonate under reducing atmosphere but not under pure CO2 and oxidizing atmospheres. The contact angle was affected by the mass of the carbonate pellet under reducing atmosphere but not under pure CO2 atmosphere. The molten carbonate spread rapidly under oxidizing atmosphere due to the surface oxidation of Ni. The wetting of porous Ni substrate was influenced by the porosity, the amount of carbonate in relation to the empty pore volume available (expressed as degree-of-filling), and the thickness of the substrate. The spreading of molten carbonate on the surface of the porous substrate, as well as penetration into the pores of the substrate was observed and the rates of these two processes were measured as accurately as possible. A linear velocity averaged over a pore was expressed in terms of the absorption rate. A simple model containing the formation of film on the pore walls and the bulk pore filling was established. The wetting of dense and porous Ni-Al alloy substrate was investigated. It revealed that the wettability of Ni-Al substrate was improved by increasing the content of Al under both pure CO2 and reducing atmospheres. The absorption rate of porous Ni-Al substrate was significantly larger than that of a porous Ni substrate of compatible porosity. The absorption rate was significantly slowed down only when the volume of molten carbonate exceeded 1.3 times the volume of empty pores inside the substrate. It was demonstrated that the mechanical strength of α-LiAlO2 matrices is improved by heat-treating at 800oC under ambient gas atmosphere. The non-heat-treated and heat-treated samples were completely wetted by molten carbonate and exhibited the same wetting behavior. A non-heat-treated α-LiAlO2 sample cracked during the wetting investigation, however, the heat-treated α-LiAlO2 matrices did not crack, presumably due to their enhanced mechanical strength.
Ph.D. in Materials Science and Engineering, May 2018
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Title: Laser Powder Bed Fusion Of Cost-Effective Non-Spherical Ti-6Al-4V Powder
Creator: Asherloo, Mohammadreza
Date: 2023
Description: This comprehensive research delves into the intricate dynamics of Laser Powder Bed Fusion (L-PBF) of Ti-6Al-4V powders, emphasizing the...
Show moreThis comprehensive research delves into the intricate dynamics of Laser Powder Bed Fusion (L-PBF) of Ti-6Al-4V powders, emphasizing the potential of non-spherical, hydride-dehydride (HDH) powders as a cost-efficient alternative to traditional spherical powders. The study systematically explores the interplay between powder morphology, granulometry, and various post-processing treatments in shaping the resultant microstructure, porosity, and mechanical properties of L-PBF fabricated Ti-6Al-4V components.Initial investigations focused on the flowability, packing density, and resultant density of L-PBF parts using HDH powders with varying size distributions. Through meticulous optimization of laser parameters, parts with a relative density exceeding 99.5% were achieved, even at production rates 1.5–2 times higher than conventional LPBF processes. Dynamic synchrotron X-ray imaging provided insights into laser-powder interactions, revealing key mechanisms of porosity formation associated with HDH powders. Further microstructural examinations highlighted the formation of columnar β grains with acicular α/α′ phases in the as-built condition. Mechanical tests, including fatigue assessments under fully-reversed tension-compression conditions, revealed the critical role of surface roughness in fatigue performance. Notably, mechanical grinding significantly improved fatigue strength, especially in the high cycle fatigue region, by eliminating surface micro-notches. X-ray diffraction analyses further elucidated the stress and micro-strain profiles, offering insights into the material's deformation mechanisms. A pivotal discovery was the presence of α/α′ on prior β/β grain boundaries, challenging the prevailing notion that high cooling rates in L-PBF preclude β/β grain boundary variant selection. Electron backscatter diffraction and synchrotron X-ray imaging illuminated the role of powder characteristics in locally modulating cooling rates, leading to β/β grain boundary α′ lath growth. Lastly, the research underscored the multifaceted interdependencies among contouring, powder granulometry, Hot Isostatic Pressing (HIP), and mechanical surface treatments. A pronounced increase in sub-surface porosities was identified when contouring was combined with fine powder granulometry. However, post-HIP treatments induced a phase transformation from martensitic α′ to a basket-weave α+β microstructure, enhancing the material's fatigue resistance to levels comparable to wrought Ti-6Al-4V. In summation, this doctoral research offers a holistic understanding of the L-PBF process for Ti-6Al-4V, emphasizing the viability of non-spherical HDH powders and providing a roadmap for parameter optimization, defect minimization, and mechanical property enhancement in L-PBF-fabricated Ti-6Al-4V structures.
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Title: Three-Dimensional Co-Culture Systems for Vascularization of Cardiac Tissue
Creator: Rodriguez Arias, Jessica A.
Date: 2023
Description: Myocardial Infarction (MI) is the partial or complete blockage of blood flow to the myocardial tissue resulting in damage and therefore loss...
Show moreMyocardial Infarction (MI) is the partial or complete blockage of blood flow to the myocardial tissue resulting in damage and therefore loss of heart function. In the U.S. every 40 seconds, someone will suffer from MI and the only available treatment is medication to treat the symptoms of heart function loss, but do not treat the underlying cause. Some attempts to treat the underlying cause have arisen in the last decades including cell-based therapies or tissue engineering therapies such as spheroid-based cardiac patches that have shown to be promising. Improvement in the mechanical properties to create suturable engineered tissues remain to be improved for ease of implantation purposes. Cell-laden hydrogel scaffolds can provide improved mechanical properties compared to biomaterial free cell-based therapies but need to allow for vascularization of the engineered tissue. Thus, the goal of this thesis is to provide preliminary studies for the use of a cell adhesive, proteolytically degradable PEG hydrogel scaffold that eventually would be used as an invitro model to evaluate engineered tissue vascularization for cardiac tissue engineering. To construct this model, important cell spheroid parameters on vascular invasion in 3D culture were investigated including the total number of cells/spheroid, the supporting cell for endothelial cells. In order to scale-up scaffolds to size of clinically relevant dimensions, a multilayered hydrogel construct visible light free-radical polymerization approach encapsulating vascular spheroids in multiple layers was also investigated. Results indicate that a total cell number of 5000 cells/spheroid aggregate were feasible due to cell sourcing. In addition, co-cultures of endothelial and mesenchymal stem cells led to maximized vascular invasion of the spheroids compared to fibroblast/endothelial co-culture and endothelial monoculture of spheroids in the hydrogel. Finally, the extent of vascularization of spheroids in each layer of the multilayered hydrogel constructs varied due to the observed differences in mechanical properties and swelling ratio of each layer due to incomplete polymerization of layers. This study demonstrated the importance of support cells and hydrogel mechanical properties in promoting vascularization of spheroid which serves as basis for building cell-laden hydrogel scaffolds for vascularization for cardiac tissues.
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Title: Design and Synthesis of New Sulfur Cathodes Containing Polysulfide Adsorbing Materials
Creator: Suzanowicz, Artur M
Date: 2023
Description: Lithium-sulfur battery (LSB) technology has tremendous prospects to substitute lithium-ion battery (LIB) technology due to its high...
Show moreLithium-sulfur battery (LSB) technology has tremendous prospects to substitute lithium-ion battery (LIB) technology due to its high theoretical specific capacity and energy density. However, escaping polysulfide intermediates (produced during the redox reaction process) from the cathode structure is the primary reason for rapid capacity fading. Suppressing the polysulfide shuttle (PSS) is a viable solution for this technology to move closer to commercialization and supersede the established LIB technology. In this dissertation, I have analyzed the challenges faced by LSBs and selected methods and materials to address these problems. I have concluded that in order to further pioneer LSBs, it is necessary to address these essential features of the sulfur cathode: superior electrical conductivity to ensure faster redox reaction kinetics and high discharge capacity, high pore volume of the cathode host to maximize sulfur loading/utilization, and polar polysulfide-resistive materials to anchor and suppress the migration of lithium polysulfides.Furthermore, a versatile, low-cost, and practical scalable synthesis method is essential for translating bench-level development to large-scale production. This dissertation covers designing and synthesizing new scalable cathode structures for lithium-sulfur batteries that are inexpensive and highly functional. The rationally chosen cathode components accommodate sulfur, suppress the migration of polysulfide intermediates via chemical interactions, enhance redox kinetics, and provide electrical conductivity to sulfur, rendering excellent electrochemical performance in terms of high initial specific capacity and good long-term cycling performance. TiO2, Ni12P5, and g-C3N4 as polysulfide adsorbing materials (PAMs) have been fully studied in this thesis along with three distinct types of host structures for lithium-sulfur batteries: Polymer, Carbon Cloth, and Reduced Graphene Oxide. I have created adaptable bulk synthesis techniques that are inexpensive, easily scalable, and suitable for bench-level research as well as large-scale manufacturing. The exceptional performance and scalability of these materials make my cathodes attractive options for the commercialization of lithium-sulfur batteries.
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Title: High-rise mix-use
Creator: Mei, Chuan
Date: 2012-05-02, 2012-05

Title: Case Study: A Comparison of Pedagogical Content Knowledge Between Coaches and Coaches/Mentees
Creator: Barone, Ana MargaritaSalinas
Date: 2024
Description: This multiple case study dissertation aimed to examine one of the domains of pedagogical content knowledge, knowledge of content and students,...
Show moreThis multiple case study dissertation aimed to examine one of the domains of pedagogical content knowledge, knowledge of content and students, between different types of elementary coaches and between coach and their respective collaborating teachers. It also investigated the impact a coaches’ background experiences have on the dynamic between coaches and teachers and the perceptions' teacher have on the effectiveness of coaching. The theoretical framework used in this qualitative study was Ball, Thames, and Phelps’ (2008) definition of PCK. Data was collected from six coaches–four instructional coaches and two math coaches–and eleven k-5th grade teachers. Data collection involved a survey, LMT assessment, and semi-structured interviews, and a thematic analysis method was conducted. The findings from the cross-case analysis resulted in ten themes, with the majority having multiple categories. One finding to one of the research questions was that there were no differences in knowledge of content and students between mathematics coaches and general instructional coaches, but other areas to further investigate emerged. Another finding was that coaches were either within the same capacity as their respective teachers or had extra knowledge of content and students. Although the majority of the coaches’ knowledge of content and students was at a higher level according to their LMT score, it does not necessarily mean that coaches are working with teachers in improving knowledge of content and students. In addition, more research is recommended in creating a pedagogical content knowledge instrument that is specific for coaches.
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Title: VTOL (Spring 2001) IPRO 318: VTOL IPRO318 Spring2001 Final Presentation
Creator: Crocco, John, Kuczaj, Mariusz, Nagarajan, Arvind, Reynolds, Tina
Date: 2001, 2001-05
Description: This project involves the design and construction of a prototype Vertical Take-Off and Landing (VTOL) airplane, capable of carrying two people...
Show moreThis project involves the design and construction of a prototype Vertical Take-Off and Landing (VTOL) airplane, capable of carrying two people. The prototype, which will be made to scale, is intended to test different control strategies. The project includes a study of the history of such concepts (commercial and military), review of the enabling technologies needed to make it a reality, market analysis, social and economic implications, the regulatory environment and other factors that help define the potential and predict the impact of such a vehicle
Sponsorship: IIT Internal R&D
Project Plan for IPRO 318: VTOL for the Spring 2001 semester
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