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Title: EVALUATION OF LISTERIA MONOCYTOGENES ENRICHMENT AND COMPOSITING PROTOCOLS FROM ENVIRONMENTAL SAMPLES
Creator: Eckert, Christine
Date: 2019
Description: Environmental sampling in a food production plant is routinely conducted using devices, such as sponges or swabs, to verify cleaning...
Show moreEnvironmental sampling in a food production plant is routinely conducted using devices, such as sponges or swabs, to verify cleaning procedures and determine if any foodborne pathogens, such as Listeria monocytogenes (L. monocytogenes), are present. The devices used for environmental monitoring are enriched to improve pathogen detection. This study aims to 1) compare the limit of detection (LOD) of L. monocytogenes of two U.S. Food and Drug Administration (FDA) enrichment procedures (i.e., Bacteriological Analytical Manual (BAM) and Compliance Document) with and without food matrix, and to 2) assess the number of samples which can be wet and dry composited without loss of sensitivity from stainless steel. To compare the LOD of L. monocytogenes using UVM and BLEB, three inoculation levels (0.27±0.07, 0.59±0.05, and 1.00±0.15 CFU per 225 mL enrichment) with 30 enrichments each were used. Results showed that there was no significant difference between the number of samples where L. monocytogenes was detected for UVM and BLEB at any of the three inoculation levels. However, the limit of detection (LOD95%) for UVM/Fraser was higher than that of BLEB (2.13 and 1.44 CFU/mL, respectively). For wet compositing, 1.24±0.34 CFU of L. monocytogenes was inoculated into 45 enrichments of UVM or BLEB without food matrix and 7.2±0.18 CFU of L. monocytogenes was inoculated into 30 enrichments of UVM or BLEB with 4.13±0.12 log CFU of native microflora from Romaine lettuce wash (RLW). Secondary composite enrichments in Fraser broth were conducted at each of four different ratios: 1:1 (1 positive:1 negative), 1:2 (1 positive: 2 negative), 1:4 (1 positive: 4 negative), and 1:7 (1 positive:7 negative). There was no significant difference between the number of samples where L. monocytogenes was detected between BLEB and UVM with or without food matrix at any of the composite ratios. When comparing wet and dry compositing enrichments from stainless steel, 10.16 × 10.16 cm areas on stainless steel plates were inoculated with 464±22 CFU (2.67±0.24 log CFU) L. monocytogenes, dried for 24 h, and sponges were used to swab the surface of the plates. The sponges were then composited (into primary enrichments for dry compositing) or the secondary enrichments were composited (for wet compositing). Compositing was conducted with RLW containing 4.13±0.02 log CFU of background microflora. There was no significant difference between the number of samples where L. monocytogenes was detected for BLEB and UVM when comparing dry or wet compositing at any of the composite ratios tested. Results of this thesis will aid in determining if compositing of environmental samples is an option when L. monocytogenes is the target pathogen.
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Title: A SCALABLE SIMULATION AND MODELING FRAMEWORK FOR EVALUATION OF SOFTWARE-DEFINED NETWORKING DESIGN AND SECURITY APPLICATIONS
Creator: Yan, Jiaqi
Date: 2019
Description: The world today is densely connected by many large-scale computer networks, supporting military applications, social communications, power...
Show moreThe world today is densely connected by many large-scale computer networks, supporting military applications, social communications, power grid facilities, cloud services, and other critical infrastructures. However, a gap has grown between the complexity of the system and the increasing need for security and resilience. We believe this gap is now reaching a tipping point, resulting in a dramatic change in the way that networks and applications are architected, developed, monitored, and protected. This trend calls for a scalable and high-fidelity network testing and evaluation platform to facilitate the transformation from in-house research ideas to real-world working solutions. With this objective, we investigate means to build a scalable and high-fidelity network testbed using container-based emulation and parallel simulation; our study focuses on the emerging software-defined networking (SDN) technology. Existing evaluation platforms facilitate the adoption of the SDN architecture and applications to production systems. However, the performance of those platforms is highly dependent on the underlying physical hardware resources. Insufficient resources would lead to undesired results, such as low experimental fidelity or slow execution speed, especially with large-scale network settings. To improve the testbed fidelity, we first develop a lightweight virtual time system for Linux container and integrate the system into a widely-used SDN emulator. A key issue with an ordinary container-based emulator is that it uses the system clock across all the containers even if a container is not being scheduled to run, which leads to the issue of both performance and temporal fidelity, especially with high workloads. We investigate virtual time approaches by precisely scaling the time of interactions between containers and physical devices. Our evaluation results indicate a definite improvement in fidelity and scalability. To improve the testbed scalability, we investigate how the centralized paradigm of SDN can be utilized to reduce the simulation workload. We explore a model abstraction technique that effectively transforms the SDN network devices to one virtualized switch model. While significantly reducing the model execution time and enabling the real-time simulation capability, our abstracted model also preserves the end-to-end forwarding behavior of the original network.With enhanced fidelity and scalability, it is realistic to utilize our network testbed to perform a security evaluation of various SDN applications. We notice that the communication network generates and processes a huge amount of data. The logically-centralized SDN control plane, on the one hand, has to process both critical control traffic and potentially big data traffic, and on the other hand, enables many efficient security solutions, such as intrusion detection, mitigation, and prevention. Recently, deep neural networks achieve state-of-the-art results across a range of hard problem spaces. We study how to utilize the big data and deep learning to secure communication networks and host entities. For classifying malicious network traffic, we have performed the feasibility study of off-line deep-learning based intrusion detection by constructing the detection engine with multiple advanced deep learning models. For malware classification on individual hosts, another necessity to secure computer systems, existing machine learning-based malware classification methods rely on handcrafted features extracted from raw binary files or disassembled code. The diversity of such features created has made it hard to build generic malware classification systems that work effectively across different operational environments. To strike a balance between generality and performance, we explore new graph convolutional neural network techniques to effectively yet efficiently classify malware programs represented as their control flow graphs.
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Title: Wind Turbine Building
Creator: Tseng, Ling Yi
Date: 5/4/2011, 2011-05
Description: Wind Turbine Building with Venturi Tube
Sponsorship: Land, Peter

Title: Reconditioning Dharavi: A Toolkit of Strategies for Incremental Development
Creator: Bhogle, Saylee Deepak
Date: 2022
Description: The 2003 Global Report on Human Settlements (Un-Habitat, 2003) defines a "slum" as a densely populated metropolitan area that is distinguished...
Show moreThe 2003 Global Report on Human Settlements (Un-Habitat, 2003) defines a "slum" as a densely populated metropolitan area that is distinguished by a variety of low-income settlements, subpar housing, and squalor. Dharavi, on the other hand, is far more than a "slum." In the heart of Mumbai, Dharavi is an economically prosperous and socially active informal town. Mumbai is a thriving metropolis with many different realities and patterns, even though it appears to be a slum filled with squatters. However, the region has recently become a hub for informal settlements and urban problems associated with poor hygiene in developing countries. People’s misconceptions about Dharavi stem from a failure to recognize its social capital and economic power: the area encompasses a variety of economic networks, production types, income levels, land tenure arrangements, and religious activities and festivities. Dharavi is made up of 85 separate groups with a strong feeling of belonging and high expectations for stability and improved economic position and living standards. It is also clear that these folks are capable of building and enhancing their shelter if they have the resources to do so. To develop all these qualities, Dharavi's Social Capital must be recognized and promoted as an asset to the city of Mumbai. A community such as Dharavi requires ‘urban acupuncture’; where mediation of the littlest kind will have the greatest effect. Dharavi, like any other "Informal" city, requires rigorous examination to be fully comprehended. It is a unique location where a large flood of migrants has managed to build jobs and their city. My underlying attitude to this location is a conflicting desire to save and replace it. The desire to save is linked to the aesthetic of informality as well as the intense sociality, diversity, and production of the streets and lanes - a fascinating and diversified urban ensemble. The desire to eliminate stems from hopeless states of sterilization, ventilation, light, open space, and congested areas. As a result, a reliable strategy for combining the two methodologies and locating a functioning arrangement should be developed. The government has been trying to redevelop this area for the past 50 years but hasn’t been successful in doing so. In contrast to the existing redevelopment plan, which promotes uniform top-down development, my concept anticipates techniques for progressive self-development, including "bottom-up" finance models and architectural approaches. After identifying various patterns and carefully examining behavior patterns, production systems, and existing community facilities, a toolkit of methods can be built that can be used in various places and "outboxes." The simple homogeneity of solutions for Dharavi's changing conditions has been avoided. Dharavi's current identity and "mixed-use" paradigm have been respected, with Home recognized as an instrument of production. The proposed design has been tested for various environmental factors using different tools for natural lighting and ventilation. The outdoor areas are also analyzed for thermal comfort since a lot of social activities take place in these areas. Communal areas have been designed to accommodate micro infrastructure systems while also increasing productivity. As a result, a system of self-development triggers has been created that can improve present conditions while also supporting the community's need for stability. Simultaneously, by focusing on property ownership as an economic driver, the proposed approach can provide a type of "social mobility" for Dharavi's residents.
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Title: RE-DEFINING LABOR HOUSING COMMUNITIES IN DUBAI
Creator: Chavadi, Sanjana Mrutyunjaya
Date: 2022
Description: From the moment they are duped into believing in a utopian lifestyle, to their day to-day working and living conditions once they arrive in...
Show moreFrom the moment they are duped into believing in a utopian lifestyle, to their day to-day working and living conditions once they arrive in the country, to the denial of theirrights for years after they are stuck in the country, the migration of workers from other countries into the Emirates is a neglected humanitarian issue. The United Arab Emirates and several other GCC countries have a heinous habit of recruiting illiterate foreigners into their country and abusing them as if they were modern-day slaves. Many nations and individuals have legal control over immigrants by applying the Kafala sponsorship system and ignoring international norms and rights established by organizations like the International Labor Organization. While the Kafala system is only one of many aspects of the whole problem, this thesis will seek to identify the influence of architecture on the lives of the South Asian labor force who work behind the beautiful façade of the United Arab Emirates by reconstructing the labor community. These colossal structures are built and shown while the individuals who construct them are ignored and hidden. Immigrant low income labor employees bear the brunt of their hard life-work imbalance with the intention of providing assistance to their family in their home nations. The labor force of Dubai becomes the major target of the terrorists, isolated from Dubai's pleasure amenities, socially detached from the rest of the population, and separated from their creations. By creating a landmark and developing a sense of social coherence, integration, and empowerment among the labor community, this initiative intends to bridge the divide and commemorate the labor community. This project will propose a new sort of community and housing typology that embraces the ideals of modularity, adaptability, and community as a solution to the immigrant worker dilemma.
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Title: Habitat 2022+
Creator: Cho, San Lae Lae
Date: 2021
Description: Globalization and urbanization have led a vast group of population to shift from rural and suburban areas to urban centers. According to the...
Show moreGlobalization and urbanization have led a vast group of population to shift from rural and suburban areas to urban centers. According to the United Nation’s (UN) projection, around 2.5 billion more people will live in the cities by 2050. For cities to accommodate such a population, cities can grow horizontally or vertically. If cities were to grow horizontally, this population would need to commute majorly by car which has a very high carbon footprint. By building vertically, the population’s commute becomes more efficient if the vertical structure is built as such is a city within a city. Although having existed for 500 years, tall buildings and skyscrapers have been topics of controversy for their excessive use of resources, ignoring environmental and contextual problems. In order to mitigate this sustainability issue, mass timber as a construction material has been recently introduced into the American market. Mass timber is the building material for a carbon neutral future according to Council on Tall Buildings and Urban Habitats (CTBUH). Another means is to grow plants around the buildings meaning they are regrowing greenery back into nature with the hopes to take a step towards mitigating climate change. In addition, with the argument of tall buildings lacking neighborhood-like qualities that for instance, a Chicago block of housing may give, more and more tall buildings around the world have tried to implement the lush spaces onto the building perimeters. These spaces with plants and trees mimicking nature can exist as both indoor and outdoor spaces. While neighborhoods have parks, these spaces or sky gardens will substitute as modified parks for skyscrapers.With psychological benefits tied to spaces linked to nature in high-rises, such spaces should be integrated in all high rise, residential buildings. Today, in addition to Covid pandemic, many people practice working from home. Meanwhile, it is human nature since birth to want to be surrounded by plants and nature, either spending time under a tree or lying on the grass. To mitigate spending excessive amounts of hours indoors, spaces linked to nature have become crucial in providing a sense of peace and reconnecting back to nature. However, currently architecture that has nature integrated, results in spaces only for the wealthy. Furthermore, architecture in the US is so commercially driven with developers aiming for the most cost effective, most efficient and largest floor areas. For nature to be more available to the living spaces of middle class and ideally working class, the city planners and city development authorities need to get involved. For instance, the city could aid by allocating some of the tax collected to build more green architecture. With the tax fund assistance from the city, high quality living of green architecture will become available and much more affordable.Another option to making living more affordable is by implementing co-living. Despite the Covid-19 pandemic, co-living remains relatively high in demand in Chicago according to Chicago Tribune. For the younger generations such as the Millennials and younger, it is predicted that due to the nature of student loan debts, these generations are less likely to be financially well off after graduation. Hence, they are less likely to establish a family as soon as the previous generations, as most people tend to start a family when they feel financially stable.Hence, in this design thesis, a certain prototype will be tested out regarding some of these issues. This is just one option to the issues above and there are many options and other nuances still available to explore.
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Title: High-integrity modeling of non-stationary Kalman Filter input error processes and application to aircraft navigation
Creator: Gallon, Elisa
Date: 2023
Description: Most navigation applications nowadays rely heavily on Global Navigation Satellite Systems (GNSSs) and inertial sensors. Both of these systems...
Show moreMost navigation applications nowadays rely heavily on Global Navigation Satellite Systems (GNSSs) and inertial sensors. Both of these systems are known to be complementary, and as such, their outputs are very often combined in an extended Kalman Filter (KF) to provide a continuous navigation solution, resistant to poor satellite geometry, as well as radio frequency interference. Additionally, recent development in safety critical applications (such as aviation) revealed the performance limitations of current algorithms (Advance Receiver Autonomous Integrity Monitoring - ARAIM) to vertical guidance down to 200 feet above the runway (LPV-200). When nominal constellations are depleted, LPV-200 can only sparsely be achieved. Exploiting satellite motion in ARAIM (for instance using a KF) could help alleviate those limitations, but would require adequate modeling of the errors, including the error's time correlation.Power Spectral Density (PSD) bounding is a methodology that provides high integrity, time correlated error models, but this approach is currently limited to stationary errors (which is rarely the case with real data), and has never been applied to navigation errors. More generally, no high integrity, time correlated error models have ever been derived for navigation errors.As a result, in the first part of this thesis, a methodology for high integrity modeling of time correlated errors is introduced. The PSD bounding methodology is extended to both stationary and non-stationary errors. In the second part of this thesis, these methodologies are applied to the 3 main error sources impacting iono-free GNSS measurements (orbit and clock errors, tropospheric errors and multipath), as well as to inertial errors.The methodology introduced in this dissertation provides high integrity time correlated error models and is applicable to any type of applications where high integrity is required (e.g. Differential GNSS - DGNSS, Aircaft Based Augmentation System - ABAS, Ground Based Augmentation System - GBAS, Space Based Augmentation System - SBAS, etc...). Additionally, the error models derived here are not only limited to high integrity applications, but could also be used in applications were the correlation over time of the errors plays an important role (such as any KF integration).In the last part of this dissertation, we focus on a specific safety critical application: aviation, and in particular ARAIM. The dissertation is concluded with an assessment of the performance improvements provided by recursive ARAIM, using those bounding dynamic error models, with respect to those models, used for baseline snapshot ARAIM. Additionally, a sensitivity analysis is performed on each of the error model parameters to assess which of them impacts the KF performance (i.e. covariance) the most.
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Title: Effect of heat treatment on microstructure and electrochemical behavior of laser powder bed fusion hydride- dehydride ti-6al-4v alloy
Creator: Delpazir, Melody Honardan
Date: 2022
Description: In powder bed additive manufacturing, feedstock and processing have an impact onfinal microstructure and properties of 3D-printed parts. While...
Show moreIn powder bed additive manufacturing, feedstock and processing have an impact onfinal microstructure and properties of 3D-printed parts. While numerous studies have evaluated 3D-printing of spherical powder, very limited research has been carried out on the processing of the non-spherical feedstock. This study is targeted specifically to the use of non-spherical Ti-6Al-4V powders in the laser powder bed fusion (L-PBF) process. Two different post-heat-treatments including hot isostatic pressing and solution treatment are applied. The microstructure evaluation, potentiodynamic polarization, and electrochemical impedance spectroscopy methods are used to characterize L-PBF processed and post- treated specimens. Though as-built part exhibits anisotropic microstructure containing acicular α′ martensite with trace amount of β phase, the heat-treated parts are composed of α+β in which length and thickness of the α-lath depends on the treatment. The below β transus heat treatment leads to the formation of a homogenized grain structures composed of α+β. Electrochemical results show that the below β transus heat-treatment had a slight positive effect on the improvement of corrosion resistivity (corrosion rate of 4.2×10-6 mmy- 1 , which is classified as an excellent ) compared to other conditions, which would be associated to the natural excellent corrosion resistance of Ti-6Al-4V alloy. This slight improvement can be ascribed by the slightly faster formation of a passive layer and its enhanced efficiency because of the presence of the fine-structured β phase in post heat- treated L-PBF processed Ti-6Al-4V alloy.
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Title: Fatigue Life Prediction for Structures with Interval Uncertainty
Creator: Desch, Michael R.
Date: 2022
Description: A new method for reliable fatigue life prediction in metal structural components is developed where uncertainties are quantified using...
Show moreA new method for reliable fatigue life prediction in metal structural components is developed where uncertainties are quantified using interval variables. Using this crack-initiation-based method, first, the uncertainties in laboratory test data for the fatigue failure of a structural detail are enumerated. This uncertainty quantification is performed through an interval-based enveloping procedure that relates the interval stress ranges to the number of cycles to failure, leading to the construction of an interval S-N relationship. Next, the uncertainties in field test data are enumerated in the extremum values of each stress range, as intervals, leading to the construction of interval stress ranges. For both the laboratory and field data uncertainty analyses, the mean stress effects are considered. Next, the interval damage accumulated over the duration of the field data is determined using the constructed interval S-N relationship and the obtained interval stress ranges. Then, the interval existing damage and interval remaining life are determined. Finally, as a conservative measure, the minimum remaining fatigue life is obtained in which all uncertainties are considered. Three numerical examples illustrating the developed method are presented, and the results are compared with results obtained by both Monte Carlo simulation and optimization. Using this method, for the numerical examples considered, it is shown that the results for bounds on the existing damage and the remaining fatigue life are sharp. Moreover, due to its set-based approach, the method is significantly more computationally efficient when compared with iterative procedures.
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Title: OPTIMUM WEIGHT STIFFNESS STRUCTURAL DESIGN
Creator: Barnett, Ralph L.
Date: 2021
Description: My adventures with flexible structures began on the IIT campus with an extracurricular undergraduate project to design an “Open House Exhibit”...
Show moreMy adventures with flexible structures began on the IIT campus with an extracurricular undergraduate project to design an “Open House Exhibit” for the Civil Engineering Department. I chose to display a reinforced concrete diving board together with a prestressed concrete diving board. Visitors enthusiastically pounced on the reinforced concrete structure whose rigid response disappointed one and all. Their indignation was transferred to the prestressed cantilever which thrust them upward from six to ten feet into the air. This unexpected response from a diving board became so dangerous that the Exhibit was unceremoniously closed. I still have the display sign, “More Bounce to the Ounce.”While still an undergraduate, I secured a part-time job at Armour Research Foundation where I responded to a bid request from Rock Island Arsenal to design the 26 foot Honest John Rocket Launcher Rail at minimum weight. This tactical weapon was transported by helicopter. I basked in the fantasy that I was Leonardo da Vinci without his artistic proclivity. Rocket launchers that droop during operation are similar in concept to a circular firing squad. So began my research into minimum weight beams based on deflection rather than strength. I searched for the shoulders of Giants. I found them in the form of mathematicians not structural engineers. I achieved a 26.5% weight savings in the 1126 pound rail by optimizing the geometry. When I developed an optimum prestressed and segmented Kentanium cermet rail, the weight savings became 89%. The right material provides a bigger bang for the buck. When my journey into optimum design began, I was armed only with analysis tools: strength, stability, and stiffness. This thesis begins with an outline of my present toolbox which contains eight design concepts: 1. Establish the Geometry, 2. Select a material from a finite number of candidates, 3. Prestress and Prestrain, 4. Statistical Screening (Proof Testing), 5. Manipulation of Boundary Conditions, 6. Energized Systems, 7. Counterweights, 8. Self-Healing and Self-Reinforcing. Four of these are used through this review which focuses on stiffness. Beginning with beams, deflection control examples are described where prestraining and prestressing techniques are used to produce both a zero-deflection beam and a method for pushing with a chain. The calculus of variations made it possible to establish optimum tapers for the flanges and webs of I-beams that minimize beam weight for a specified deflection or, because of reciprocity, minimize beam deflection for a specified beam weight. An anomaly is encountered that enables one to achieve an upward, downward, or zero deflection with a set of beams of vanishing weight. In addition, special circumstances are defined where a uniform strength design is identical to the minimum weight design based on a specific deflection. Closed form solutions are obtained for a variety of loading scenarios. One problem is presented for self-weight that leads to a nonlinear integral equation. The optimum stiffness-weight design of trusses is undertaken where the area distribution of the truss members is optimized using Lagrange’s method of undetermined multipliers. Once again, we obtain a degenerate case where upward, downward, and zero deflection conditions can be met with an infinite set of trusses of vanishing weight. We photograph a simply supported truss under a downward load that leads to an upward deflection at one of the joints. Special loading conditions are identified that lead to uniform stress designs that are identical to the minimum weight designs based on deflections. This study provides a Segway into the world of minimum weight strength design of trusses. The resulting Maxwell and Michell trusses sometimes display the optimum distribution of bar areas from the point of view of stiffness. Many practitioners are under the mistaken impression that Michell structures, when they exist, provide the optimum truss profile for stiffness. Unfortunately, the optimum array of truss joints based on deflection does not exist. For both trusses and beams the optimum distribution of mass is shown to be necessary and sufficient; the sufficiency is established using well-known inequalities. The role of stiffness in the design of columns is explored in our final chapter. This cringe-worthy history of column analysis begins our study as a warning to practitioners who use analysis as their basis for design and especially optimum design. Conventional elastic and inelastic buckling theories provide little insight into the design of columns. The fundamentals of minimum weight column design are presented to show the power of design theory in contrast to analysis. Both prismatic and tapered columns are studied with one surprise result; the optimum taper gives rise to a uniform bending stress (without axial stresses). It was fun to see that in 1733 Lagrange made a mistake in calculus of variations that led to the incorrect solution for the optimum tapered column. It took 78 years before Clausen obtained the correct solution. The problem has been revisited by William Prager and again by the author who used dynamic programming. Of course, we all got the same result which is a dreadful solid circular tapered column that is heavier than any ordinary waterpipe. The best of a class is not necessarily the best possible design. Under the heading, “Intuition is a good servant but a bad master,” we introduce the notions of tension members that buckle, columns constructed from spherical beads, optimum rigging of crane booms, and deflection reversal of beam-columns. In several places we observe that the weight of optimum columns is proportional to P^α where P is the axial load and α is less than unity. We fail to tell the reader that this implies that minimum weight columns require putting all your eggs in one basket; one column under load P is lighter than two columns each under load P/2. On the other hand, we expose the solid circular column as the least efficient shape among all regular polygons, the equilateral triangle is the best. Indeed, there is a family of rectangles that are superior to the circular cross-section. Finally, the author’s prestressed tubular column is introduced that is pressurized to eliminate local buckling. Euler’s buckling can always be eliminated with a thin-wall section of sufficient width without a weight penalty. The weight of the balloon-like member is proportional to (PL) which implies that at last we have a compressive member that meets the requirement of a Michell structure. Bundling of pressurized gas columns are possible without a weight penalty. Further, the column is insensitive to most imperfections. It is the lightest known column for small structural indices (P/L^2 ). When coupled with circulating cryogenic liquid as a prestressing system, a limiting column has a vanishing weight.
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Title: SEPARATING NOBLE GASES SUCH AS KRYPTON AND XENON FROM NUCLEAR POWER PLANTS OFF-GAS USING DD3R ZEOLITIC MEMBRANES: A COMPUTATIONAL MOLECULAR DYNAMICS STUDY
Creator: BASHMMAKH, BANDAR JAMAL S.
Date: 2021
Description: Noble gas fission products generated within nuclear power reactors, such as Kr and Xe, are currently discharged into the atmosphere. This...
Show moreNoble gas fission products generated within nuclear power reactors, such as Kr and Xe, are currently discharged into the atmosphere. This practice has a major economic drawback because of the high value associated with some of these gases. Zeolites, nanoporous materials suitable for gas separation processes, have become of major interest due to the potentially high selectivity for such separations. We have used nonequilibrium molecular dynamics to investigate the separation performance of DD3R framework zeolitic membranes (using LAMMPS software package) for such separations. Our studies have shown that the DD3R membrane shows promise for high selectivity ratios of Kr over Xe. The effects of pressure, temperature and pure vs. mixture gas feed conditions are studied in this work to understand at the molecular level the mechanisms of these (Kr/Xe) separations. MD runs show an agreement with most experimental trends in the permeation of Kr/Xe pure and mixed gases using DD3R zeolite with high separation factor, despite the absence of Xe complete permeation through the membrane because of MD timescale limitation, signaling much slower diffusion in comparison to Kr which is a desired trend in looking for high separation factors.
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Title: INFORMAL AREAS UPGRADING STRATEGIES: THE CASE OF ADEN CITY-YEMEN
Creator: Ba Tis, Ahmed Abdullah Obaid
Date: 2022
Description: Informal areas are global problems that pose a threat to the urban environment and their consequences prompted urgently to search for...
Show moreInformal areas are global problems that pose a threat to the urban environment and their consequences prompted urgently to search for solutions and methods to address these problems and limit their effects. This thesis examines the issue of informal areas in Yemen. Informal areas are houses built on illegal public or private real estate. In Yemen, these illegal areas began as a relatively new phenomenon and since then have grown at an extremely rapid rate. Increasing rates of urbanization, poverty, and unemployment have led to the rapid rise of slums and informal housing in Yemen. The UN-Habitat database of global urban indicators estimates that 60% of Yemen's urban population lives in informal settlements. The cities most affected by the rapid growth of informal settlements include Taiz, Al Hudaydah, Sana'a, and Aden. The Yemeni government has done little to address the growth of informal areas. However, there was growing concern about this issue, and governmental and non-state actors alike began to consider new approaches to urban policy development and implementation. The importance of the thesis is that it will limit the spread of slums in Aden in the future, and it will also be a good starting point for further research and studies on the issue of developing the problem of informal areas in Yemen. There are many ways to deal with the problem of informal areas, including demolition and resettlement, and development upgrading and each method differs according to the region’s conditions, whether the urban, social economic, location of the area. This study focuses on urban upgrading to clarify its concepts, types and strategies, because it has become one of the most appropriate ways to deal with informal areas and to reach a sustainable urban environment. The thesis aims to find solutions for informal areas in Yemen and limit their growth in the future by preparing a new strategy for dealing with informal areas, in light of the experiences of other countries, and in line with the reality of Yemen.
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Title: Establishing Bisphenol A Degradation and Enhancing Microbial Fuel Cell Performance by Biofilm Optimization of Shewanella Oneidensis MR1
Creator: Zhou, Jiacheng
Date: 2023
Description: Bisphenol A (BPA) has been widely used as a plasticizer in the production of synthetic polymers, such as those used in food storage containers...
Show moreBisphenol A (BPA) has been widely used as a plasticizer in the production of synthetic polymers, such as those used in food storage containers and bottles. However, BPA interferes with endocrine systems, causing carcinogenicity, immunotoxicity, and embryotoxicity. Biological water treatment processes scarcely remove BPA, owing to the poor BPA degradability and efficiency of the applied microorganisms. Shewanella oneidensis has been studied and used for the biodegradation process in wastewater treatment because of its excellent extracellular electron transfer properties. In this work, we engineered S. oneidensis MR1 to enable BPA degradation by producing ferredoxin (Fdbisd) and cytochrome P450 (P450bisd) originating from Sphingomonas bisphenolicum AO1. The engineered S. oneidensis exhibited a higher BPA degradation efficiency than that of Escherichia coli producing the same enzymes. The endogenous ferredoxin and ferredoxin reductase of S. oneidensis participated in BPA degradation, and overexpression of mtrC, omcA, and So0521, which encode S. oneidensis cytochromes, decreased BPA. We developed BPA-degrading S. oneidensis biofilms. We measured these optimized BPA-degrading S. oneidensis biofilm in a single chamber microbial fuel cell formed on different carbon electrodes by morphology. Cyclic voltammetry and electrochemical impedance spectroscopy were measured to analyze the biofilm-electrode performance. The biofilm colonization was also measured by confocal laser scanning microscope and scanning electron microscope. And the developed microbial fuel cell was used to degrade BPA and the biofilm developed on different type of carbon anodes was identified. This study provides insights into biocatalyst utilization for the biological degradation of toxic organic compounds.
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Title: Carrier phase multipath characterization and frequency-domain bounding
Creator: Benz, Chloe
Date: 2022
Description: Safely relying on Global Navigation Satellite Systems (GNSS) measurements for position estimation using multi-sensor navigation algorithms,...
Show moreSafely relying on Global Navigation Satellite Systems (GNSS) measurements for position estimation using multi-sensor navigation algorithms, especially in critical phases of flight – such as takeoff or landing – requires precise knowledge of the errors affecting position estimates and their extrema values at any time. This work investigates a method for characterization and power-spectral density (PSD) bounding of GNSS carrier phase multipath error intended for use in sensor fusion for aircraft navigation. In this dissertation, two methods of GNSS carrier phase multipath characterization are explored: single frequency dual antenna (DA) and single antenna dual frequency (DF). However, since not all aircraft are equipped with multiple GNSS antennas, because the DA method entails a meticulous tracking of the lever arm between the two antennas, and as multipath seen by two antennas in a short baseline configuration may cancel out, the DF method is preferred and is the main emphasis of this work. By subtracting carrier phase measurements collected by a receiver overtwo distinct frequencies, a composite measurement containing ionospheric delay and carrier phase multipath is obtained. The ionospheric delay has slower dynamics than multipath, so it is removed using a high pass filter. The filter cutoff frequency is carefully picked based on a study of ionospheric delay dynamics. The DF method is validated on a rooftop GPS carrier phase dataset, and finally, directions and considerations for its ultimate intended use on airborne collected GNSS carrier phase data are provided.
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Title: Cities on the Move: Envisioning Cityscape in the Autonomous Vehicle Era
Creator: Lee, Hyo Eun
Date: 2023
Description: As cities have developed in response to a rapidly changing environment since the industrial revolution, a variety of circumstances and issues...
Show moreAs cities have developed in response to a rapidly changing environment since the industrial revolution, a variety of circumstances and issues have arisen. In cities, technological development and the rise of private automobiles have been related to urban sprawl, traffic congestion, environmental degradation, and mobility inequalities. Currently, autonomous vehicles are bringing a paradigm shift in mobility as technological innovations accompany the fourth industrial revolution. As cities undergo renewal through new mobility, recent developments in driverless technologies should be considered for their long-term impact on the built environment. The purpose of this thesis is to propose a design, along with a set of scenarios, for a transportation hub in the era of autonomous vehicles to address today's complex mobility requirements. Through bringing together existing case studies, research on autonomous vehicles, and drawing conclusions regarding the relationship between mobility and urban landscapes, this thesis explores how autonomous vehicles will affect the future built environment in a set of timelines. Considering the future transportation hub will require programs and infrastructure to support autonomous vehicles, this thesis also provides a vision of the future of transportation modes and how they interact. Finally, a transportation hub design model and an automation city model for the AV era will be proposed.
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Title: DESIGN FOR COMFORT: DESIGN BUILDING ENVELOPE TO IMPROVE THERMAL COMFORT FOR RESIDENTIAL BUILDINGS IN AL-MUKALA, YEMEN
Creator: Bakarmom, Aamena Mubarak Saeed
Date: 2021
Description: This thesis is about the research into the design of building envelopes to reduce energy consumption and moderate thermal performance of the...
Show moreThis thesis is about the research into the design of building envelopes to reduce energy consumption and moderate thermal performance of the residential buildings in Yemen, which is in an arid climate. A suitable building envelope is important because of the building occupants’ thermal comfort. The most important question is how architects could implement high-performance envelope technologies in their designs, especially in residential buildings. These technologies have some basic principles which are applied differently from one region to another. One of the most promising strategies applied to house envelopes in a hot-dry climate is the passive cooling design. This thesis reviews the results of other research in the same region that discuss proper parameters of building envelopes such as form, width, climate, walls, materials, and windows design. Passive cooling strategies will be the key to providing potential design building envelopes that provide thermal comfort and reduce energy use. This study applies the natural ventilation principle (single-sided, cross- or stack ventilation), thermal mass, and shaded devices. The research methods were to collect data and create quantitative models to analyze the data. From this analysis, I suggest specific architecture guidelines for design in residential buildings which could improve comfort in indoor spaces for occupants.
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Title: CABLE MODELING AND FAULTSTUDY FOR THE lIT PERFECT POWER SYSTEM
Creator: Gupta, Abhinav
Date: 2011-05-02, 2011-05
Description: IIT has taken part in the smart grid initiative by converting the existing radial distribution network into a looped network to increase the...
Show moreIIT has taken part in the smart grid initiative by converting the existing radial distribution network into a looped network to increase the reliability of the system as part of the ’Perfect Power’ project. A total of 7 loops have been planned with the help of fast fault clearing relays (’Vista Switches’). As part of the project, the cable is modeled using the various impedance calculators and was also done using the PSCADrsoftware. With the obtained impedance values from the impedance calculators, the cables were analyzed under various outage/contingency cases. They include base case power flows of the old IIT distribution network as well as the Loop 3 of the perfect power project implemented and open circuit analysis and short circuit analysis of the Loop 3 alone. Also, with the help of the fault current values from the short circuit study we can analysis the relay settings and operations and review the later for the newly installed relays. And finally, the cable fault classifier was designed using the Artificial Neural Network (ANN) method in MATLABrand PSCADrsoftware. Here we model the cable using the impedance calculated and collect the voltage and current samples from the two ends of the cable which is given as input to the ANN classifier and the same is tested for accuracy.
M.S. in Electrical Engineering, May 2011
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Title: WIND MICRO-CLIMATE CONFORMATION IN HOT DRY CITIES; RIYADH
Creator: Alhawsah, Saeed Idris
Date: 2019
Description: Recently, the transformation in urban development in Saudi Arabia has caused abrupt and sporadic change to its desert climate. Careful...
Show moreRecently, the transformation in urban development in Saudi Arabia has caused abrupt and sporadic change to its desert climate. Careful environmental consideration of vernacular architecture practices is lost by the vast modernization. The significant changes of modernization contain desertification, sand rapping due to massive urban construction, and urban heat islands, all that has created a severe issue with sandstorms. Saudi’s modernization changed sandstorms phenomena from its seasonal occasions to a frequent rapid increase as a result of the urban inability to maintain its naturally mild and soothing condition. All the global incidents from the natural refugees in Gobi Desert, China, to the 1930s U.S. dustbowl are evident to the urban environmental disturbance. This research is an environmental investigation to reduce the sandstorm effects in Saudi Arabia through designing multiple territorial landscape interventions to filter out the sandstorms and trap its sediments to avoid reoccurring sandstorms.
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Title: BEYOND THE GREEN IDEAL - RESHAPING CHICAGO SOUTH LOOP
Creator: Hoeflich Brune, Vivian Eliese
Date: 2015, 2015-12
Description: Analyzing the growing metropolis, this research questions the relation between the built and open environment on its process of densification....
Show moreAnalyzing the growing metropolis, this research questions the relation between the built and open environment on its process of densification. Urban areas depend upon landscape and broader natural areas to be sustained. The current system, in which landscape is the center of extraction and production and cities centers of consumption, has an unhealthy one-direction flow of energy and materials. By linking the urban landscape, buildings, and parks, a new ecological infrastructure breaks this traditional system and can become the own natural living system of the urban environment. By preserving existing open spaces in the city and introducing new ones, this thesis explores how to increase urban density and, at the same time, create new social-ecological associations. Movement from outside city to its center resulted in urban population increase and recently is transforming the near South region of Chicago. Therefore, this study explores the introduction of a set of open spaces for collective experiences in two scales. First, is investigated the impact of inserting a new landscape infrastructure on the existing urban fabric of Chicago South Loop neighborhood. Through the study of the current site, the identification of underutilized or public lots set a framework for intervention, adding available spots into a network of open spaces that support diverse programs for the area. Rethinking the traditional urban block consists the second studied topic, exploring the relation of built and open spaces on a smaller scale. Not only the continuity to the open space infrastructure is essential for the project but also the creation of a new urban lifestyle inside one city block and its nearby areas. Being on a strategic site connected to the public transportation system and Museum Campus, the proposal works as a condensed program center. Both local neighborhood and a broader public of visitors and tourists are attended, combining a multiplicity of programs, users, built and open space typologies.
M.S. in Architecture, December 2015
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Title: THERMAL AND MECHANICAL ANALYSIS OF ELECTRON BEAM ADDITIVE MANUFACTURED TI-6AL-4V BUILD PLATE
Creator: Cao, Jun
Date: 2017, 2017-07
Description: Electron Beam Additive Manufacturing (EBAM), used to fabricate net or nearnet- shaped components based on a sliced CAD model, offers a...
Show moreElectron Beam Additive Manufacturing (EBAM), used to fabricate net or nearnet- shaped components based on a sliced CAD model, offers a potential alternative solution for the processing of titanium components, especially for large parts. However, the components fabricated using EBAM exhibit significant difficulties in quality control and quality assurance due to lack of knowledge of thermo-mechanical-metallurgical relationship. In this work, the thermo-mechanical behavior of wire-feed EBAM for largescale Ti-6Al-4V build plates has been investigated computationally and experimentally, with special attention to the distortion and residual stress, as well as the microstructural evolution. A 3D transient fully coupled thermo-mechanical finite element (FE) model was built, calibrated, and rigorously validated. To ensure the accuracy of the model, the bulk residual strain distribution was measured using neutron diffraction (ND), and the numerically simulated thermal profiles were physically simulated using a Gleeble® 3500, in addition to the conventional model validation methods. Good agreement was found between the simulation results and experimental measurements. A series of simulations were performed to determine the optimum process conditions. The simulation results indicated that preheating, increasing deposition power and scan rate, and decreasing interval cooling time effectively mitigates the distortion and residual stress. For EBAM Ti-6Al-4V build plates, increasing the energy input and reducing the heat loss renders smaller temperature difference and thermal expansion mismatch, consequently, leading to a lower level of distortion and residual stress. The deposited cladding was characterized by large columnar grains growing across layers, a bottom region with repeated macroscopic bands and a top region without these bands. The band structure exhibits mostly colony α. A fine basket-weave structure is observed above the band structure, and a coarse basket-weave structure is observed below the band structure. The simulated thermal profiles were used to understand the observed microstructure. It was found that the microstructure variation in the cladding of EBAM Ti-6Al-4V build plates is strongly dependent on the peak temperature within the (α+β) phase region, and heating rate and cooling rate have insignificant effects on it. The non-equilibrium solid-solid phase transformation of Ti-6Al-4V under continuous heating/cooling were experimentally investigated. The kinetics of phase transformation was quantitively studied and modeled using a non-isothermal JMAK (Johnson-Mehl-Avrami-Kolmorgorov) model, with the activation energy QA=123.9 kJ/mole, JMAK exponent n=1.8, and the calculated ln (k0) varied between 9.15 to 10.6 for different heating rate.
Ph.D. in Materials Science and Engineering, July 2017
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