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(9,301 - 9,320 of 9,825)
Pages
- Title
- Leon's Bar-B-Q: Pick Up Orders or Dine at Tables
- Creator
- Gordon, Robert Philip, Robert Gordon Associates
- Date
- 1980-03-10
- Description
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Full color architectural sketch of the interior of a location of the Leon's Bar-B-Q restaurant franchise.
- Collection
- Robert Philip Gordon papers, 1963-2010
- Title
- Leon's Bar-B-Q: View from 'The Street'
- Creator
- Gordon, Robert Philip, Robert Gordon Associates
- Date
- 1980-02
- Description
-
Full color architectural sketch of a location of the Leon's Bar-B-Q restaurant franchise.
- Collection
- Robert Philip Gordon papers, 1963-2010
- Title
- Icosahedron Guest House on Indiana Dunes, Exterior, ca. 1970s
- Creator
- Gordon, Robert Philip
- Date
- 1970-1979
- Description
-
Photograph of the exterior of an Indiana Dunes guest house in the form of an icosahedron, comprised of prefabricated triangular panels. Date...
Show morePhotograph of the exterior of an Indiana Dunes guest house in the form of an icosahedron, comprised of prefabricated triangular panels. Date of photograph unknown. Date range listed is approximate.
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- Robert Philip Gordon papers, 1963-2010
- Title
- Technology Center Today and Tomorrow
- Creator
- Illinois Institute of Technology
- Date
- 1947
- Description
-
Fundraising booklet for distribution to businesses and entrepreneurs soliciting funds for the development of the new campus buildings and...
Show moreFundraising booklet for distribution to businesses and entrepreneurs soliciting funds for the development of the new campus buildings and academic programs of Illinois Institute of Technology. At the time of the booklet's publication, the earliest of Mies van der Rohe's buildings on the Illinois Tech campus had been completed, with others under construction. The booklet includes a plan of the proposed Mies campus as well as drawings and descriptions of the buildings yet to be built. Some extant copies of the booklet include Technology Center of Tomorrow in the Making Today (see http://hdl.handle.net/10560/islandora:1011682), an insert with an update on campus construction.
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- Fund Raising Brochures collection, 1941-1950
- Title
- State Street, looking north from Randolph Street, Chicago, Illinois, 1962
- Creator
- Illinois Institute of Technology
- Date
- 1962
- Description
-
Photograph of State Street in Chicago's loop, looking north from Randolph Street. Date of photograph determined from the movie titles visible...
Show morePhotograph of State Street in Chicago's loop, looking north from Randolph Street. Date of photograph determined from the movie titles visible on the theater marquees.
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- Office of Communications and Marketing photographs, 1905-1999
- Title
- Civil Engineering professor Eben Vey with students in classroom, Illinois Institute of Technology, Chicago, Illinois, ca. 1960s
- Date
- 1960-1969
- Description
-
Photograph of Civil Engineering professor Eben Vey with students. Vey was appointed an assistant professor of Mechanics at Illinois Tech in...
Show morePhotograph of Civil Engineering professor Eben Vey with students. Vey was appointed an assistant professor of Mechanics at Illinois Tech in the fall of 1948. Vey later became a professor of Civil Engineering and chairman of the Department of Civil Engineering before taking leave of the university in 1977. Photographer unknown. Date of photograph is unknown. Date range listed is approximate.
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- Office of Communications and Marketing photographs, 1905-1999
- Title
- Civil Engineering professor Eben Vey with students in classroom, Illinois Institute of Technology, Chicago, Illinois, ca. 1960s
- Date
- 1960-1969
- Description
-
Photograph of Civil Engineering professor Eben Vey with students. Vey was appointed an assistant professor of Mechanics at Illinois Tech in...
Show morePhotograph of Civil Engineering professor Eben Vey with students. Vey was appointed an assistant professor of Mechanics at Illinois Tech in the fall of 1948. Vey later became a professor of Civil Engineering and chairman of the Department of Civil Engineering before taking leave of the university in 1977. Photographer unknown. Date of photograph is unknown. Date range listed is approximate.
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- Office of Communications and Marketing photographs, 1905-1999
- Title
- Nate Thomas, Illinois Institute of Technology, Chicago, IL, 1968-1973
- Date
- 1968-1973
- Description
-
Photograph of Nate Thomas. Thomas worked at Illinois Tech in various positions, first as part of the Computing Center in 1965. Thomas later...
Show morePhotograph of Nate Thomas. Thomas worked at Illinois Tech in various positions, first as part of the Computing Center in 1965. Thomas later served as Assistant Director of Co-Op Education , Director of Admission, head of Minority Affairs, and Vice President for External Affairs. Thomas was instrumental in recruiting students from underserved communities into STEM programs at Illinois Tech, and founded the Early Identification program in 1974 in order to attract and support diverse students interested in STEM, architecture, and other programs at Illinois Tech. Photographer unknown. Date of photograph is unknown. Date range listed is approximate.
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- Office of Communications and Marketing photographs, 1905-1999
- Title
- Nate Thomas, Illinois Institute of Technology, Chicago, IL, 1968-1973
- Date
- 1968-1973
- Description
-
Photograph of Nate Thomas. Thomas worked at Illinois Tech in various positions, first as part of the Computing Center in 1965. Thomas later...
Show morePhotograph of Nate Thomas. Thomas worked at Illinois Tech in various positions, first as part of the Computing Center in 1965. Thomas later served as Assistant Director of Co-Op Education , Director of Admission, head of Minority Affairs, and Vice President for External Affairs. Thomas was instrumental in recruiting students from underserved communities into STEM programs at Illinois Tech, and founded the Early Identification program in 1974 in order to attract and support diverse students interested in STEM, architecture, and other programs at Illinois Tech. Photographer unknown. Date of photograph is unknown. Date range listed is approximate.
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- Office of Communications and Marketing photographs, 1905-1999
- Title
- Quantification of Vascular Permeability in the Retina Using Fluorescein Videoangiography Data as a Biomarker for Early Diabetic Retinopathy
- Creator
- Kayaalp Nalbant, Elif
- Date
- 2023
- Description
-
Diabetic retinopathy, which is the most common reason for blindness in the working-age population, affects over one-third of those who have...
Show moreDiabetic retinopathy, which is the most common reason for blindness in the working-age population, affects over one-third of those who have had diabetes for over ten years. High blood sugar level (hyperglycemia) in the blood damages blood vessels and tight junction at the blood-retinal barrier (BRB). Chronic inflammation leads to changes in vascular health, and over time blood vessels tend to get damaged and exhibit higher “leakage” or permeability. In the late stage of DR, hemorrhages can occur, leading to irreversible damage of neuronal tissue in the retina and vision loss. In the clinic, there are some biomarkers and imaging modalities used to diagnose DR based on some of the more severe products of DR (e.g., hemorrhage), but there is no non-invasive, highly sensitive method to detect diabetic retinopathy before clinical signs occur, when mitigating therapies could be more effective. In this thesis, indicator dilution theory was explored to modeling the temporal dynamics of fluorescein in the retina after intravenous injection, with an aim to quantitatively map subtle changes in retinal blood flow and vascular permeability that could preempt subsequent irreversible damage. Specifically, a simplified version of indicator dilution theory—namely the “adiabatic approximation in tissue homogeneity” (AATH) model—was used to estimate physiological parameters such as the blood flow (F) and the extraction fraction (E: a parameter coupled with vascular permeability) from retinal fluorescein videoangiography data. The AATH fitting protocol was optimized through simulations using a more complex model (the AATH-vascular heterogeneity model, AATH-VH). It was determined that a two-step least square fitting method was more sensitive than a single-step least square fitting of AATH to simulated data to evaluate vascular permeability in early diabetic retinopathy. The optimized data analysis protocol was then evaluated in an initial clinical study comparing healthy control subjects to those with moderate non-proliferative DR. Volumetric blood flow and retinal vascular permeability maps were compared between patient groups with clear increases in extraction fraction observed in the mild NPDR patients compared to control. These promising early data have been the foundation to an ongoing 5 year study tracking 100 Diabetic patients with no DR so see if early changes in vascular permeability can predict which patients are more likely to progress to DR.
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- Title
- Efficient management of uncertain data
- Creator
- Feng, Su
- Date
- 2023
- Description
-
Uncertainty arises naturally in many application domains. It can be caused by an uncertain data source (sensor errors, noise, etc.). Data...
Show moreUncertainty arises naturally in many application domains. It can be caused by an uncertain data source (sensor errors, noise, etc.). Data preprocessing techniques (data curation, data integration, etc.) can also results in uncertainty to the data. Analyzing uncertain data without accounting for its uncertainty can create hard to trace errors, with severe real world implications. Certain answers are a principled method for coping with the uncertainty that arises in many practical data management tasks. Unfortunately, this method is expensive and may exclude useful (if uncertain) answers. Other techniques from incomplete database record and propagate more detailed uncertainty information. However, most of these approaches are either too expensive to be practical, or only focus on a narrow class of queries and only work for a specific representation. In this thesis, we investigate models and query semantics for uncertain data management and present a framework that is general and practically efficient, backed up by fundamental theoretical foundations and with formally proven correctness guarantees. We first propose Uncertainty Annotated Databases (UA-DB), which combine an under- and over-approximation of certain answers to combine the reliability of certain answers with the performance of a classical database system. We then introduce attribute-annotated uncertain databases (AU-DB), which extend the UA-DB model with attribute-level annotations that record bounds on the values of an attribute across all possible worlds. AU-DB extends UA-DBs to encode a compact over-approximation of possible answers which is necessary to support non-monotone queries including aggregation and set difference. With a further extension to AU-DB that supports ranking and windowed aggregation queries using native implementation on modern DBMS, our approaches scale to complex queries and large datasets, and produces accurate results. Furthermore, they significantly outperforms alternative methods for uncertain data management.
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- Title
- High School Mathematics Teachers’ Conceptions of Nature of Mathematics (NOM) and How Prior Learning Environments Affect These Conceptions
- Creator
- Elefteriou, Katherine
- Date
- 2023
- Description
-
Literature shows that the Nature of Mathematics Knowledge (NOMK) dates back to the era of Plato and Aristotle (Dossey, 1992). It suggests that...
Show moreLiterature shows that the Nature of Mathematics Knowledge (NOMK) dates back to the era of Plato and Aristotle (Dossey, 1992). It suggests that mathematics teachers’ beliefs, views, conceptions, and preferences about NOM influence the way in which they teach mathematics. It is important to understand how these conceptions are formed, which may evolve consciously or unconsciously from their experiences. Teachers’ experiences as students of mathematics, their family, school environment, cultural, and social experiences influence their behavior including their decisions, actions, class organization, learning activities, and students’ achievement (Beswick, 2012; Ernest, 2008; Thompson1984). Yet, there is no NCTM standard on NOM (Gfeller, 1999).The purpose of the present study was to assess high school mathematics teachers’ NOMK conceptions, and to explore how these conceptions have been influenced by their personal and educational experiences as students in learning mathematics. Another objective of this study was to explore whether the teachers’ years of mathematics teaching experience, and their level of education have any influence on their NOMK beliefs. The sample consisted of 52 high school mathematics teachers, who were certified to teach secondary mathematics, and who had at least three years of mathematics teaching experience. Two instruments were used to collect the data, 1) the VNOM D instrument to assess the teachers’ beliefs regarding the NOMK aspects, and 2) the demographics instrument to collect information on the teachers’ demographics, and on their experiences as students of mathematics. Interviews were also used to enhance the findings. Results showed that participants had strong beliefs regarding their NOMK, and that their years of experience, and level of education influenced their NOMK beliefs.
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- Title
- Effects of Microstructure Engineering on Laser Powder Bed Fusion Processed Superalloy IN718 through Inoculant Addition
- Creator
- Ho, I-Ting
- Date
- 2023
- Description
-
Additive manufacturing (AM) techniques can now be utilized as innovative tools that provide unlimited design flexibility for the fabrication...
Show moreAdditive manufacturing (AM) techniques can now be utilized as innovative tools that provide unlimited design flexibility for the fabrication of geometrically complex metallic structures. For production of Ni-base superalloy components used in advanced gas turbine engines, laser powder bed fusion (L-PBF), which is one of the AM techniques, is frequently used as it allows good metallurgical bonding of powder feedstock and simultaneously enables development of ultra-efficient power systems for aerospace propulsion, space exploration and power generation. One of the major challenges associated with additively manufactured Ni-base superalloy components is that the extreme temperature gradients encountered during processing negatively impact the underlying microstructure and mechanical properties of the material. Although the macroscopic shape and chemistry of the additively fabricated part may be identical to the conventionally manufactured part, the resulting properties are usually compromised. In an effort to make Ni-base superalloys more amenable for processing via additive manufacturing, varying levels of benign inoculants that promote may heterogeneously grain nucleation were blended into Inconel 718 (IN718) powder feedstock and used for processing via L-PBF to characterize the microstructural evolution. In the first study, 0.2 wt. % of micron-sized CoAl2O4 flakes was found to effectively change the grain morphology during the L-PBF process leading to significant reduction in crystallographic texture and thus resulting elastic anisotropy. Dispersion of nano-oxides resulting from the reduction of CoAl2O4 particles also contributed to improved tensile strength and steady creep strain rate. It should be noted, however, that, the multiple iterations of remelting as the result of deposition of new layers dissolved the Co-rich particles reduced from CoAl2O4 inoculants. Instead of having nucleation events contributed by elemental Co, the oxide agglomerates as a result of Marangoni convection seemed to be the major contribution to facilitating grain refinement by inhibiting the heat transfer in the surroundings. On the other hand, addition CoAl2O4 particles appeared to generally reduce the melt pool width while increase the melt pool depth by inhibiting the degree of heat transfer and Marangoni flow. The changes in melt pool dimension aided in improving the relative density and surface roughness of the bulk samples by generating better metallurgical bonding to the subsequent layers. As the trade-off, however, the changes in melt pool physics also enhanced the tendency for epitaxial growth and hence retarded the columnar-to-equiaxed transition unless oxide agglomerates are present. In addition to CoAl2O4, candidates including Co, TaCr2, TiB2, and CeO2 particles were also considered to be blended with the powder feedstock of IN718. After the L-PBF process, different degree of microstructural evolution was characterized with the addition of Co, TaCr2, TiB2, or CeO2 particles. It was found that the physical presence of inoculants may change the melt pool geometries that accounted for a comparatively more columnar-grained structure with <101> texture in samples containing Co and TaCr2 particles while a relatively equiaxed-grained structure with <001> texture in samples containing TiB2. The comparison between samples containing TiB2 and CeO2 further indicates that the phase transformation induced agglomeration will also reduce the effectiveness of inoculants due to decreasing nuclei density. Findings from this investigation demonstrate the resulting grain structure upon L-PBF can be profoundly impacted by both chemistry and physical properties of the inoculants. These effects may potentially be harnessed to effectively engineer the microstructure and optimize the properties of L-PBF processed Ni-base superalloys.
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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
- A Novel CNFET SRAM-Based Computing-In-Memory Design and Low Power Techniques for AI Accelerator
- Creator
- Kim, Young Bae
- Date
- 2023
- Description
-
Power consumption and data processing speed of integrated circuits (ICs) is an increasing concern in many emerging Artificial Intelligence (AI...
Show morePower consumption and data processing speed of integrated circuits (ICs) is an increasing concern in many emerging Artificial Intelligence (AI) applications, such as autonomous vehicles and Internet of Things (IoT). In addition, according to the 2020 International Technology Road map for Semiconductors (ITRS), the high power consumption trend of AI chips far exceeds the power requirements. As a result, power optimization techniques are highly regarded in nowadays AI chip designs. There are various low-power methodologies from the system level to the layout level, and we are focusing on transistor level and register transfer level (RTL) through this thesis. In this thesis, we propose a novel ultra-low power voltage-based computing-in- memory (CIM) design with a new SRAM bit cell structure for AI Accelerator. The basic working principle of CIM (Computing-in-memory) is to use the existing internal embedded memory array (e.g. SRAM) instead of external memory, and it reduces unnecessary access to external memory by calculating with internal embedded mem- ory. Since the proposed our SRAM bit cell uses a single bitline for CIM calculation with decoupled read and write operations, it supports much higher energy eciency. In addition, to separate read and write operations, the stack structure of the read unit minimizes leakage power consumption. Moreover, the proposed bit cell structure provides better read and write stability due to the isolated read path, write path and greater pull-up ratio. Compared to the state-of-the-art SRAM-CIM, our proposed SRAM-CIM does not require extra transistors for CIM vector-matrix multiplication. We implemented a 16k (128⇥128) bit cell array for the computation of 128x neurons, and used 64x binary inputs (0 or 1) and 64⇥128 binary weights (-1 or +1) values for the binary neural networks (BNNs). Each row of the bit cell array corresponding to a single neuron consists of a total of 128 cells, 64x cells for dot-product and 64x replicas cells for ADC reference. And 64x replicas cells consist of 32x cells for ADC reference and 32x cells for o↵set calibration. We used a row-by-row ADC for the quantized outputs of each neuron, which supports 1-7 bits of output for each neuron. The ADC uses the sweeping method using 32x duplicate bit cells, and the sweep cycle is set to 2N1 +1, where N is the number of output bits. The simulation is performed at room temperature (27C) using 32nm CNFET and 20nm FinFET technology via Synopsys Hspice, and all transistors in bitcells use the minimum size considering the area, power, and speed. The proposed SRAM-CIM has reduced power consumption for vector-matrix multiplication by 99.96% compared to the existing state-of-the-art SRAM-CIM. Moreover, because of the separated reading unit from an internal node of latch, there is no feedback from the read access circuit, which makes it read static noise margin (SNM) free. Furthermore, for the low power AI accelerator design, we propose a new AI accelerator design method that applies low power techniques such as bus specific clock gating (BSCG) and local explicit clock gating (LECG) at the register-transfer- level (RT-level). And evaluates them on the Xilinx ZCU-102 FPGA SoC hardware platform and 45nm technology for ASIC, respectively. It measures dynamic power using a commercial EDA tool, and chooses only a subset of FFs to be gated selectively based on their switching activities. We achieve up to a 53.21% power reduction in the ASIC implementation and saved 32.72% of the dynamic power dissipation in the FPGA implementation. This shows that our RTL low power schemes have a powerful possibility of dynamic power reduction when applied to the FPGA design flow and ASIC design flow for the implementation of the AI system.
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- Title
- Growth Kinetics of Listeria monocytogenes and Salmonella enterica on Rehydrated Enoki and Wood Ear Mushrooms during Storage
- Creator
- George, Josephina
- Date
- 2023
- Description
-
Plant foods, such as fruits and vegetables, that have been dehydrated do not support the growth of pathogenic microorganisms. Recent...
Show morePlant foods, such as fruits and vegetables, that have been dehydrated do not support the growth of pathogenic microorganisms. Recent listeriosis and salmonellosis outbreaks in the U.S. have been associated with imported specialty mushrooms. These mushrooms are commonly sold fresh or dehydrated. This study evaluated the survival and growth of two foodborne pathogens Listeria. monocytogenes and Salmonella. enterica on dehydrated mushrooms during both rehydration at 25 or 5℃ and storage at 5, 10, or 25℃. Fresh enoki and wood ear mushrooms were dehydrated for 24 h at 60°C. Dehydrated mushrooms were inoculated with a four-strain cocktail of S. enterica or L. monocytogenes at 4 log CFU/g. Mushrooms were dried for 1 h, followed by rehydration for 2 h with 5 or 25°C (water and air temperature). Rehydrated mushrooms were stored at 5, 10, or 25°C for up to 14 d. The pathogens were enumerated at 0, 1, 3, 6, 9 and 14 d. Three independent trials with triplicate samples at each time point were completed. Population differences were evaluated via Student’s t-test; p<0.05 was considered significant. The growth rates were determined by DMFit in Excel. Overall, the growth rates of L. monocytogenes and S. enterica on enoki mushrooms were significantly higher when the mushrooms were rehydrated at 25℃ and stored at 25℃ (P<0.05). The growth rates were 2.69 log CFU/g per day and 3.56 log CFU/g per day, for L. monocytogenes and S. enterica respectively. Since the growth of pathogens on wood ear mushrooms during rehydration and storage was considerably less and below the level of enumeration, enrichment of the pathogens was conducted. The pathogens could be suppressed during rehydration due to less nutrient contents and antimicrobial properties of wood ear. The result of this study outlines the importance of refrigerated storage temperature and time combination for safety during rehydration and subsequent storage of the mushrooms.
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- Title
- Characterization and Migration of Silver Nanoparticles from Electron-Beam Irradiated Low-Density Polyethylene
- Creator
- Donovan, Dylan
- Date
- 2023
- Description
-
Polymer nanocomposites (PNCs) and engineered nanomaterials (ENMs) may find use in a wide range of commercial applications, including food and...
Show morePolymer nanocomposites (PNCs) and engineered nanomaterials (ENMs) may find use in a wide range of commercial applications, including food and medical product packaging. Migration of nanofillers from polymer nanocomposites into food matrices could be a source of human dietary exposure to ENMs. Electron beam (e-beam) irradiation is a processing method used for microbial inactivation as well as for modifying properties of polymer films, such as stretch resistance and shrink tension. Process treatment of nanotechnology-based packaging materials either for sterilization or for strengthening of the polymer films may have a significant effect on the migration of ENMs into food matrices. The primary objective of this study is to investigate the effect of e-beam irradiation treatments of LDPE containing silver nanoparticles (AgNPs) and the subsequent migration of AgNPs into a food simulant under intended use conditions. The study observes a correlation between e-beam irradiation dose quantity and the release of AgNPs into a food simulant.
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- Title
- Investigating The Impact of Tall Building Ordinances (TBOs) on the Evolution of Ultra-Tall Buildings Typology: Case Studies in Chicago and Dubai
- Creator
- Alkoud, Amjad
- Date
- 2023
- Description
-
Zoning ordinances are instruments that tangibly and intangibly shape cities; control urban morphology, demography, and visual identity; and...
Show moreZoning ordinances are instruments that tangibly and intangibly shape cities; control urban morphology, demography, and visual identity; and determine the inhabitants' life quality, well-being, and comfort. Tall building ordinances (TBOs), in turn, control the vertical growth of cities and the development of tall buildings as distinctive actors in the built environment today. With the recent proliferation of developing Ultra-tall buildings in cities around the world, ordinances should offer flexibility, adaptability, and responsiveness to the dynamic nature of emerging needs and technological potentials.This dissertation investigates the emergence of Ultra-tall buildings as a new typology in major metropolises and the interaction between the building ordinances and the construction of Ultra-tall. The work presented in this dissertation implements two primary research methods: cross-sectional surveys and longitudinal studies, documenting supertall buildings completed in two major cities, Chicago and Dubai. The discussions and findings are supported by structured interviews with architects and engineers actively involved in designing and constructing Ultra-tall buildings. The cross-sectional survey comprises all supertall buildings (i.e., buildings above 1000 feet in height) completed as of 2022 in Chicago, the cradle of the "modern" high-rise with 318 towers of 100-plus meters and eight supertall towers of 300-plus meters; and Dubai, the new experimental land of supertall construction with 298 towers of 100-plus meters and 28 towers of 300-plus meters height. The longitudinal case studies provide additional information and knowledge about selected examples in Chicago and Dubai, derived from personal structured interviews conducted in both cities. Several additional survey cases from China, NYC, and London were investigated for their importance and uniqueness in supporting the research discussions and findings. This research aims to bridge the gap between the building ordinance literature and Ultra-tall building design practices on the one hand. On the other hand, it sheds light on the necessity to realize Ultra-tall buildings as a distinct typology entitled to its particular set of ordinances.The research findings are intended to help architects, engineers, policymakers, and planning authorities ensure a sustainable socioeconomic future and mitigate the negative impact of Ultra-tall constructions in major cities. This goal is assumed to be achieved by developing a set of recommendations, strategies, and universal criteria to implement a more flexible and responsive approach toward emerging human needs and technologies.
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- Title
- Quantifying Localization Safety for State-of-the-Art Mobile Robot Estimation Algorithms
- Creator
- Abdul Hafez, Osama Mutie Fahad
- Date
- 2023
- Description
-
In mobile robotics, localization safety is quantified using covariance matrix or particle spread.However, such methods are insufficient for...
Show moreIn mobile robotics, localization safety is quantified using covariance matrix or particle spread.However, such methods are insufficient for mission or life-critical applications, like Autonomous Vehicles (AVs), because they only reflect nominal sensor noise without considering sensor measurement faults. Sensor faults are unknown deterministic errors that cannot be modeled using a zero mean Gaussian distribution. Ignoring sensor faults, in such applications, might result in large localization errors, which in turn deceives other reliant systems, like the controller, leading to catastrophic consequences, such as traffic accidents for AVs. Thus, other techniques need to be used to conservatively quantify pose safety.This thesis builds upon previous research in aviation safety, or what is referred to as \textit{integrity monitoring}, to quantify localization safety for mobile robots that use state-of-the-art state estimators (as localizers).Specifically, this thesis utilizes the localization \textit{integrity risk} metric, as a measure of localization safety, which is defined as the probability of the robot's pose estimate error to lie outside pre-determined acceptable limits while an alarm is not triggered. Unlike open-sky aviation applications, where Global Navigation Satellite Systems (GNSS) signals are available, mobile robots operate in GNSS-denied, or in the best case GNSS-degraded, environments, which demands utilizing more complex set of sensors to guarantee an acceptable level of localization safety. This thesis provides a conservative measure of localization safety by rigorously upper-bounding the integrity risk while accounting for both nominal lidar noise and unmodeled lidar measurement faults.The contributions of this thesis include the design and analysis of practical integrity monitoring and failure detection procedures for mobile robots utilizing map-based particle filtering, a recursive integrity monitoring method for mobile robots utilizing map-based fixed lag smoothing for both solution-separation and chi-squared as failure detectors, the synthesis of an integrity monitoring procedure for mobile robots utilizing Extended Kalman Filter-based Simultaneous Localization And Mapping (EKF-based SLAM), and a Model Predictive Control (MPC) framework that is capable of planning mobile robot's trajectory to follow a predefined robot path while maintaining a predefined minimum level of mobile robot localization safety. The proposed methodologies are validated using both simulation and experimental results conducted in real-world urban university campus environments.
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- Title
- Designs and Optimizations of Oblivious Data Access for Mitigating Access Pattern Leakage
- Creator
- Che, Yuezhi
- Date
- 2023
- Description
-
In today’s data-driven world, data outsourcing has grown, increasing the importance of data security and privacy. Data encryption, while...
Show moreIn today’s data-driven world, data outsourcing has grown, increasing the importance of data security and privacy. Data encryption, while providing some protection, is insufficient against side-channel attacks such as access pattern leakage. This thesis focuses on designing and optimizing efficient oblivious access methods to enhance data security and privacy. Traditional solutions, like Oblivious RAM (ORAM), often impose significant overheads, limiting their market adoption. Our research proposes novel oblivious data access schemes tailored to specific applications, systems, and contexts. This approach enables us to identify critical vulnerabilities and performance bottlenecks, and balance performance, security, and other relevant parameters. In this thesis, I present four published works in Chapters 3 to 6, demonstrating the effectiveness of my proposed methods: (1) optimizing Ring ORAM for multi-channel memory systems, (2) introducing a multi-range supported ORAM for locality-aware applications, (3) proposing an oblivious data access solution for NVM hybrid memory systems, and (4) developing an oblivious access method for deep neural networks (DNNs), ensuring privacy without sacrificing performance. These contributions address unique challenges across application domains, enhancing data security and privacy in contemporary computing systems. This thesis provides a comprehensive investigation of targeted oblivious access methods, highlighting the benefits of the proposed designs, and contributing to more effective solutions for access pattern leakage mitigation, ultimately improving data security and privacy in contemporary computing systems.
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