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Title: Modeling and Optimization of Embedded Active Flow Control Systems
Creator: Henry, James M.
Date: 2024
Description: This thesis presents research focused on the aerodynamic performance of circulation control on two-dimensional and quasi-two-dimensional wings...
Show moreThis thesis presents research focused on the aerodynamic performance of circulation control on two-dimensional and quasi-two-dimensional wings. Aerodynamic loads, namely lift, drag, and moment coefficients, are measured through Reynolds Averaged Navier Stokes (RANS) modeling and wind tunnel experiment. A simplified and parameterized RANS model is presented as a rapidly iterable approach to estimating the performance of trailing-edge circulation control on two dimensional airfoils, with the hypothesis that an optimized airfoil shape can be found which maximizes the lift coefficient increment generated by circulation control, through modification of the wing profile. The simplified modeling setup is compared with more conventional approaches to numerical simulation of circulation control. The performance of the simplified modeling scheme is then compared with wind tunnel studies, for both steady-state and dynamic performance, as functions of both momentum coefficient dCμ and chord-based Reynolds number Re_c. The dynamic performance for the model is studied to find an analog to the theoretical unsteady models of Wagner and Theodorsen. An adjoint optimization framework is used to find an optimal airfoil profile for circulation control. The optimized profile is then compared in both a simulation and a wind tunnel test study against a NACA0015 airfoil. In simulation, improvement between 12% and 15% is seen for the lift control authority for all values of dCμ and Re_c tested. In experiment, the optimized profile demonstrated improvements of up to 28% in lift control authority, dCL/dCμfor values of Cμ, and decreased performance for higher values of Cμ.
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Title: EXPANDING THE HEP FRONTIER WITH BOOSTED B-TAGS AND THE QCD POWER SPECTRUM
Creator: Pedersen, Keith
Date: 2018, 2018-05
Description: As particle physics continues to expand into the high-energy and highluminosity frontiers, it is encountering event topologies with extreme...
Show moreAs particle physics continues to expand into the high-energy and highluminosity frontiers, it is encountering event topologies with extreme boosts and intense pileup. This creates unique challenges that limit our ability to use QCD jets to find new physics and conduct precision tests of the standard model. In this thesis, I present two tools that greatly expand our ability to use jets for these important purposes: (i) The μx boosted-bottom jet tag, whose O(100) signal to background ratio does not falter as jet pT exceeds 1TeV, and which is robust to pileup due to its foundation in boosted kinematics. (ii) Power jets, the first stage in a larger program to harness the power spectrum of QCD radiation to better utilize the vast amount of information collected about each collider event. Using the full power spectrum of a detected event, the power jets framework not only provides an accurate and precise recovery of jet kinematics, but also naturally facilitates a global fit to pileup intensity (rather than a local subtraction of pileup energy, which inadvertently strips soft QCD that belongs to the hard scatter).
Ph.D. in Physics, May 2018
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Title: INCORPORATION OF NATURAL SENSORY FEEDBACK TO BRAIN MACHINE INTERFACE WITH HAND EXOSKELETON
Creator: Qian, Kai
Date: 2018, 2018-05
Description: The feasibility of a brain-machine interface (BMI) system that links the brain to an external device has been demonstrated for both non-human...
Show moreThe feasibility of a brain-machine interface (BMI) system that links the brain to an external device has been demonstrated for both non-human and human subjects. However, BMI controlled robotic arm movements are usually slow, jerky and imprecise. Many of these problems can be attributed to a lack of somatosensory (tactile, proprioception, etc.) feedback. For a large segment of potential users who have motor impairments but intact sensation, use of an exoskeleton as the external device could provide the natural sensory feedback to improve BMI control. This is especially true for the hand with its incredibly rich sensory innervation. Currently, however, there is no hand exoskeleton available for non-human primate BMI research. In this dissertation, a hand exoskeleton platform was developed for an index finger - thumb precision grip task. The system was first employed as a scientific apparatus to explore the sensory responses in primary motor cortex (M1) to sinusoidal inputs of position and force. Neural firing rate patterns were found to be strongly entrained to the sinusoidal stimulus, with a predominance of neurons responding to joint movement rather than fingertip force. The phase-locking patterns to sinusoidal stimuli were much clearer and more stable for joint movement than for fingertip force as well. Second, the hand exoskeleton system was validated in a real-time BMI-controlled isometric grip force task. Prompted by cues on a computer screen, the monkey used cortical signals to control the grip force produced by the exoskeleton. The exoskeleton drove either the monkey’s own hand (natural sensory feedback condition) or an artificial hand (visual feedback only condition). Although improvements in performance for both conditions were observed over the relatively short training period, it was difficult to differentiate between the efficacy of the two conditions. Interestingly, for both conditions the monkey tried to use a similar neural strategy in controlling grip force as to the one used in natural grip behavior, in which a majority of the neurons recorded exhibited temporal reduction of the firing rates during the force production phase. Overall, the hand exoskeleton platform proved to be not only a powerful platform in BMI research but also an important tool for investigating sensory processing. This new platform should facilitate future experiments which will further insight into BMI design and the neural mechanisms underlying movement control.
Ph.D. in Biomedical Engineering, May 2018
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Title: HARDWARE ACCELERATION OF HASHING FUNCTIONS FOR CRYPTOCURRENCY MINING USING ZYNQ SOC
Creator: Rajagopal, Vignesh
Date: 2018, 2018-05
Description: Cryptocurrencies rely on secure hashing algorithms and public key cryptography to keep transactions secure, disallow double spending, and keep...
Show moreCryptocurrencies rely on secure hashing algorithms and public key cryptography to keep transactions secure, disallow double spending, and keep a decentralized ledger. In a bitcoin’s lifetime, the most computationally intensive work is done at conception. New bitcoins are brought into the ecosystem by a process named mining. While mining encompasses various mathematical functions and nuances that will be described in this thesis, the key element is a double SHA256 function, which has to be performed many times until the specified criterion is met. The focus in this thesis will be to speed up one iteration of this double hash function by making optimizations in hardware. The hashing function along with its optimizations will be implemented on Xilinx’s Zedboard, which contains both an FPGA chip as well as a microprocessor (ZYNQ7). Using Xilinx’s product suite, the double hashing function was taken from a high abstraction level language to low-level hardware deployment, following the design flow and applying various optimization methods, or directives. Some of the methods employed were array partitioning, pipelining, and loop unrolling. The primary goal in this thesis is not to simply achieve low latency; rather it is to reach a compromise between latency, power consumption, and area usage. Techniques are explored and tested both individually and in hybrid solutions and various practical tradeoffs are considered. Miners have to take into account the associated increase in hardware and power costs that come with high-area hardware implementations. After all, a miner is not going to want a setup that costs more to run than the worth of the Bitcoins mined. Therefore, the focus in this thesis is to optimize the double SHA256 hashing function for speed, area, and power. The work done has pointed towards array partitioning – a technique that brings frequently accessed variables from BRAM into registers. It allows for the best combination of decreased latency with only marginal increases in power and area. Utilized alongside pipelining, in tests, a speedup of 2.83x was achieved over an auto-optimized hardware implementation while decreasing both power consumption and the usage of look-up tables (LUTs) and flip-flops (FFs). Implementing these optimizations into a real-life mining rig, complete with comparator, incrementing nonce, and live block header construction has been left as future work. In addition, optimizing various other mathematical functions of the Bitcoin life cycle lies beyond the scope of this thesis. As such, this work serves to reduce latency for a single iteration of the double SHA256 function as it applies to Bitcoin mining, while taking into account practical considerations for the miner. The result is an IP core that can be instantiated 10-15 times in a modest FPGA chip and used in the development of a full mining rig.
M.S. in Electrical Engineering, May 2018
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Title: DESIGN FLOW OF ADVANCED ENCRYPTION STANDARD HARDWARE ACCELERATION USING ZYNQ SYSTEM-aN-CHIP
Creator: Rarick, Samuel
Date: 2018, 2018-05
Description: The Advanced Encryption Standard (AES) is a symmetric encryption algorithm used by the United States government to protect sensitive...
Show moreThe Advanced Encryption Standard (AES) is a symmetric encryption algorithm used by the United States government to protect sensitive information. In this study, three implementations of a 256-bit AES algorithm are presented to accelerate the computational elements of the algorithm: a low-area, high-performance, and hybrid implementation. The three implementations were developed for the ZedBoard development board which contains a Zynq-7000 SoC. The Zynq-7000 SoC contains both a processing system (dual-core ARM processor) and programmable logic (Xilinx-7 FPGA). This relation between hardware and software of the Zynq-7000 SoC was exploited by implementing the key schedule algorithm of AES on the dual-core ARM processor, while implementing the AES encryption core on the Xilinx-7 FPGA. A high-level synthesis design flow was followed for its flexibility and reduction of development time. The result for latency is about a 2.5 times acceleration for the low-area implementation, a 12 times acceleration for the hybrid implementation, and a 44 times acceleration for the high-performance implementation. For the area results, the high-performance implementation can theoretically fit 13 encryption cores on the ZedBoard, while both the low-area and hybrid implementations can theoretically fit 35 encryption cores on the ZedBoard.
M.S. in Computer Engineering, May 2018
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Title: CASE-ADAPTIVE PROCESSING FOR IMPROVING ACCURACY IN COMPUTER-AIDED DIAGNOSIS OF BREAST CANCER
Creator: Sainz De Cea, Maria Victoria
Date: 2018, 2018-05
Description: Breast cancer is the most commonly diagnosed cancer among women (apart from skin cancer) in the US. If detected early, the five-year survival...
Show moreBreast cancer is the most commonly diagnosed cancer among women (apart from skin cancer) in the US. If detected early, the five-year survival rate is 99%. Because of this, early detection of breast cancer has been an extensively studied topic over the years, and screening mammography is the gold standard for this purpose. Microcalcifications (MCs) are tiny calcium deposits that appear as bright spots in mammogram images, and they can be an early sign of breast cancer in asymptomatic women. Computer aided diagnosis (CAD) tools can be used to assist radiologists in detecting MCs and classifying them as benign or malignant. CAD of breast cancer is often hampered by the presence of false positives (FP) among the detected MCs when a reasonable sensitivity level is achieved. The FPs can be caused by MC-like noise, linear structures, etc. Due to the wide range of factors causing FPs, there is a great inter-patient variability, which can degrade the performance of CAD systems. In this work, we aim to reduce the inter-patient variability of CAD systems in order to improve the performance in both MC detection (Computer aided detection or CADe) and classification of MC clusters (Computer aided diagnosis or CADx). The first part of this thesis focuses on MC detection. We first develop a framework for estimating the accuracy in detection of individual MCs within a lesion region. This framework is general and can be applied to any MC detector. The number of FP detections can vary greatly from patient to patient, so having this knowledge will be useful to make decisions in both CADe and CADx systems. Secondly, we present a case-adaptive method for CADe based on Bayes’ risks, where a distribution is fit to the FPs from a mammogram under consideration, based on which the optimal detection threshold is determined for each patient. Finally we present an outlier approach for detection of individual MCs in a lesion region. This approach is based on the fact that individual MCs are usually different from the FPs (brighter, larger in extent), so they can be detected as statistical outliers. The outlier detection is done in a case-by-case basis, which can yield not only a reduction in the number of FPs but also an increase on the uniformity of the detection accuracy among different cases. The second part of the thesis is focused on CADx. We apply the methods developed in the first part to improve the uniformity and performance in the classification of detected lesions as benign or malignant. For this purpose we first present a quality factor approach for adjusting the contribution of the detected individual MCs to the final feature set. Those detections with a higher quality factor can have more impact in the final features, therefore mitigating the effect of the FP detections. Finally, we use the estimated detection accuracy to determine the optimal detection operating threshold. This is shown to boost the CADx performance.
Ph.D. in Electrical Engineering, May 2018
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Title: Medical Tourism Tower: board4
Creator: Liu, Sha, Zhao, Jie
Date: 2011, 2011-05
Description: This is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery...
Show moreThis is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery hospitals along with a luxury hotel.
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Title: CHARACTERIZING THE ROLE OF PCL1 IN YEAST PHEROMONE RECEPTOR POLARIZATION
Creator: Pai, Chih-yu
Date: 2015, 2015-05
Description: Chemotropism, or directed cell growth in response to a chemical gradient, plays a vital role in many processes, including pollen tube...
Show moreChemotropism, or directed cell growth in response to a chemical gradient, plays a vital role in many processes, including pollen tube formation, axon guidance, angiogenesis, and fungal infections. One of the best-studied models of eukaryotic directional sensing is Saccharomyces cerevisiae, also known as budding yeast. Chemotropic growth relies on both pheromone receptor and its associated G-protein. In vegetative yeast cells, the pheromone receptor is uniformly distributed on the plasma membrane. Upon receptor activation, G~y is released from Ga and G~ is subsequently phosphorylated at multiple residues. Free G~y signals to the nucleus via a MAPK cascade that causes G1 cell cycle arrest and induction of mating specific genes. In addition, G~y recruits various polarity proteins that orient actin-directed secretion to a specific growth site, and newly synthesized receptors are delivered to it. This pheromone-induced receptor polarization appears as "crescents" where the mating projection later forms. However, how yeast cell interpret the external signals and establish the chemotropic growth site remains unknown. Here, we characterized the role of Pcl1, which is a cyclin for the CDK Ph085, and which has been implicated in polarization during budding. It is known that G~ phosphorylation plays a role in receptor polarization and chemotropism. Because G~ has a consensus phosphorylation motif for Ph085, and because G~ and Pcl1 showed a genetic interaction, we hypothesized that Ph085-Pcl1 regulates receptor polarity through G~ phosphorylation. Our results showed Pcl1 localized towards mating projection during mating response. Moreover, Pcl1 and G~ exhibit a direct interaction in response to pheromone. Lastly Ph085 inactivation also appears to affect receptor polarity. Hence, our data are consistent with the hypothesis that Pho85-Pcl1 facilitates receptor polarity establishment by phosphorylating G~.
M.S. in Biology, May 2015
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Title: CHARACTERIZATION OF SPATIALLY MODULATED MULTICOMPONENT MATERIALS DEPOSITED BY ATOMIC LAYER DEPOSITION
Creator: Becker, Nicholas
Date: 2014, 2014-07
Description: Spatially modulated multicomponent materials are used in a variety of fields and industries. In this dissertation Atomic Layer Deposition (ALD...
Show moreSpatially modulated multicomponent materials are used in a variety of fields and industries. In this dissertation Atomic Layer Deposition (ALD) will be used to create two types of spatially modulated multicomponent materials: Erbium doped Yttrium Oxide (Er+3:Y2O3) for high energy lasers and standard reference materials for Synchrotron based X-ray Fluorescence (SXRF) and Scanning Transmission X-ray Microscopy (STXM). Er+3:Y2O3 was produced and the inter- and intra-layer doping of each film was controlled by the cycle ratio of ALD grown Er2O3:Y2O3 and by the steric hinderance of erbium precursor ligands, respectively. Photolumenescent Spectroscopy and X-ray di↵raction measurements showed that all films of Er+3:Y2O3 were crystalline as deposited, with no evidence of amorphous, or glassy, emission lines in the PLS spectra. Photoluminescent Lifetime (PLL) measurements were performed to prove that ALD can be used to control both inter- and intra-layer doping. PLL was shown to vary with both Er2O3:Y2O3 cycle ratio and with Erbium precursor growth rate, increasing to a maximum of 6.5ms. This is the longest PLL reported for ALD grown Er+3:Y2O3. Results from Rutherford backscattering spectroscopy, X-ray absorption fine structure spectroscopy, and ultraviolet to visible light spectroscopy are presented to verify inter- and intra-layer doping control. Standard reference materials for SXRF and STXM were produced via ALD on transmission electron microscopy windows and native oxide silicon. Materials produced were Fe2O3, TiO2 , ZnO, Al2O3, and Y2O3. Films were analyzed with SXRF, and SXTM to determine the optical density and from this the areal density was calculated using preexisting standard reference materials and absorption value charts. It was found that the RBS measurements were more precise, and were within the error associated with the SXRF and STXM measurements.
Ph.D. in Physics, July 2014
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Title: VARIOUS ATTACHMENT AND RECOVERY OF MS2 FROM THE CONTACT SURFACES OF GLASS AND POLYMERS
Creator: Yan, Runan
Date: 2018, 2018-05
Description: Human enteric viruses are recognized as a primary etiology for foodborne diseases in the United States. Enteric viruses are highly contagious...
Show moreHuman enteric viruses are recognized as a primary etiology for foodborne diseases in the United States. Enteric viruses are highly contagious and easily transmitted via the interaction (attachment or adhesion) with biotic or abiotic surfaces followed by extended survival and then transferred to food during food preparation. Containers and tools for handling foods are commonly manufactured of polymers. These abiotic surfaces could serve as vehicles for potential viral transmission to foods. The research objective is to evaluate factors that potentially affect virus adhesion to substrate surfaces thus altering viral disease transmission, including (i) variables of the food-contact materials (e.g., polymers and glass), and (ii) finish of food-contact surfaces (e.g., smooth or rough). The virus recovery comparison by infectivity, and the surface topography by atomic force microscopy (AFM) and profiler were employed in this study. The food-contact materials used in this study include lab-made high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP), and commercial polyvinyl chloride (PVC) and two types of glass. Smooth polymer sheets were made by injection molding; and some were abraded with sand paper to produce rough surfaces. Coliphage MS2 suspension, as the inoculum, was completely air-dried first on substrate surfaces, and then cold-stored for 24 hrs at 4 °C to allow sufficient contact time between viruses and surface before the viruses were eluted and recovered. Two elution protocols were developed to accommodate different sizes of the substrates, with similar virus elution efficiency confirmed. Viruses in eluates were quantified by double agar layer plaque assay. Potential alterations in virus recovery from a substrate after surfactant sodium dodecyl sulfate (SDS) pre-treatment were also tested. Via AFM measurement, smooth substrate surfaces exhibited overall uniform nanoscale profiles, with average RMS approximately ranging from 0.4 to 4.4 nm. Rough surfaces were characterized by a profiler due to greater roughness than the upper measurement limitation of AFM (2 μm). Pinholes with an approximate average 21 nm in diameter were found in cover glass, which probably contributed to significantly lower virus recoveries (32 ± 6%, averaged from 5 trials, n = 18) than that from bottom glass (48 ± 9%, averaged from 9 trials, n = 26) where no holes were observed. For smooth polymer surfaces, the greatest virus recovery was from PP with an average of 76 ± 12% (n = 14), followed by HDPE (54 ± 6%, n = 20) and LDPE (53 ± 6%, n = 7). Interestingly, virus recoveries were always significantly lower from the corresponding rough surfaces (p < 0.001), indicating rough substrate topography could potentially serve as reservoirs for viruses. By pre-treating a thin layer of SDS at various concentrations to mask the substrate surface hydrophobicity, the virus recovery from PVC surface increased by up to 21%. These data potentially assist in selecting appropriate food-contact materials and how to construct the contact surfaces in order to eliminate similar size-foodborne viruses being trapped or retained on food-contact surfaces during cleaning or intentional removal, and thus prevent foodborne viral disease transmission.
M.S. in Food Safety and Technology, May 2018
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Title: SWITCHING OSCILLATION OF HIGH-FREQUENCY WIDE BANDGAP POWER SEMICONDUCTOR DEVICES
Creator: Liu, Tianjiao
Date: 2018, 2018-05
Description: Wide bandgap (WBG) power semiconductor devices can operate at high voltage, high switching frequency and high temperature. However, the...
Show moreWide bandgap (WBG) power semiconductor devices can operate at high voltage, high switching frequency and high temperature. However, the extremely fast switching characteristics, when combining parasitic components from the device package and power electronics circuit, are unfortunately accompanied by undesirable switching oscillations. In this thesis, switching oscillations observed in the WBG devices are studied. Firstly, a survey on oscillations in the general high-frequency power electronics circuit is carried out including the impacts of oscillation, causes of oscillation and mitigation of oscillation. Moreover, theoretical studies of the WBG switching performance and switching oscillations are performed based on spectrum analysis. The mathematical derivation reveals that the oscillation tends to enhance certain regions in the electromagnetic interference (EMI) spectrum by inducing a noise peak. In addition, modeling and analysis of silicon carbide (SiC) MOSFET switching oscillations are presented by developing equivalent circuit models for the turn-on and turn-off switching, respectively. Damping techniques design guidelines are provided based on the modeling analysis. Last but not least, a new technique to accurately characterize the parasitic inductances of power devices in discrete and module packages based on two-port scattering (S) parameters measurement is proposed. The approach is first verified with high frequency circuit simulation and then experimentally validated through case studies of a number of discrete devices and power modules.
Ph.D. in Electrical Engineering, May 2018
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Title: Medical Tourism Tower
Creator: Liu, Sha, Zhao, Jie
Date: 2011, 2011-05
Description: This is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery...
Show moreThis is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery hospitals along with a luxury hotel.
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Title: Medical Tourism Tower: board1
Creator: Liu, Sha, Zhao, Jie
Date: 2011, 2011-05
Description: This is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery...
Show moreThis is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery hospitals along with a luxury hotel.
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Title: Medical Tourism Tower: board2
Creator: Liu, Sha, Zhao, Jie
Date: 2011, 2011-05
Description: This is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery...
Show moreThis is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery hospitals along with a luxury hotel.
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Title: Medical Tourism Tower: board3
Creator: Liu, Sha, Zhao, Jie
Date: 2011, 2011-05
Description: This is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery...
Show moreThis is the design of a medical tourism tower located in Seoul, Korea. It is a mixed-use high rise which includes three plastic surgery hospitals along with a luxury hotel.
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Title: AUTONOMOUS INDOOR PATHFINDING USING NEURAL NETWORKS IN COMPLEX SCENES
Creator: Vasudevan, Vignesh
Date: 2018, 2018-05
Description: Navigation to a specific destination indoors can be a challenge due to different reasons such as visual impairment, unknown environments, etc....
Show moreNavigation to a specific destination indoors can be a challenge due to different reasons such as visual impairment, unknown environments, etc. There has been much work done to solve this issue such as indoor positioning systems, navigation using sensors and even using a robotic guide. In this thesis, a novel and straightforward method of path planning (including object avoidance) is presented as a way of navigating to a desired location within a complex environment. The system proposed uses the combination of depth information from an RGB-D camera and the object information from a Neural Network based object identification technique, to efficiently calculate and plan a path in real-time, to a pre-specified destination. Persons to be helped are identified using object detection, and the most practical path to the desired destination is calculated. The path information would be sent to the handheld device of the person being helped in the suitable form of interface, such as visual, audio, etc. The surveillance type nature of the system enables it to help multiple persons in the same area. The model was tested in a controlled environment with one individual person being guided to nearby specified locations. The testing showed promising results, validating the performance of the system.
M.S. in Electrical Engineering, May 2018
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Title: MACHINE LEARNING METHODS FOR PREDICTING GLOBAL AND LOCAL CRIME IN AN URBAN AREA
Creator: Navarro Comes, Eric
Date: 2018, 2018-05
Description: In recent years there has been growing interest in development of computer methods that can model and predict crime events for crime...
Show moreIn recent years there has been growing interest in development of computer methods that can model and predict crime events for crime prevention in law enforcement agencies. A popular example is the creation of crime density maps which are used to provide early-warning information about potential hotspots of crime in an urban area. One important aspect of predictive policing is to identify the time and place of likely crime occurrence so as to prevent future crime events. The ability to make accurate, timely predictions can be particularly important for optimizing police resource allocation in an urban area. This thesis focuses on developing machine learning techniques in crime analysis and prevention for predicting the overall crime trend in an urban area, as well as the likelihood of crime occurrence in a given local area during a time period. By using crime data extracted from the Citizen and Law Enforcement Analysis and Reporting (CLEAR) system in the city of Chicago, we demonstrate that state-of-the-art learning algorithms can achieve improved prediction accuracy over traditional methods based on time series models. We then study prediction techniques for determining the likelihood of crime occurrence at a specific local area during a given time window. We demonstrate these techniques in the operational framework of the Strategic Decision Support Centers (SDSCs) in the Chicago Police Department, where only a small number (up to six) surveillance cameras can be monitored simultaneously at any given time in a single district. We apply prediction techniques to select those cameras that most likely have crime events happening within their viewsheds during a determined time window, thereby maximizing the crime monitoring efficiency. Using these models, we can achieve higher accuracy than the methods based on local crime density alone.
M.S. in Electrical Engineering, May 2018
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Title: THE ROLE OF THE BAXΔ2 C-TERMINAL STRUCTURE IN CASPASE-8- MEDIATED CELL DEATH OF HUMAN COLORECTAL CARCINOMA CELLS
Creator: Nelson, Adam
Date: 2018, 2018-05
Description: BaxΔ2 is an isoform of the proapoptotic Bcl-2 family member Bax that promotes cell death via caspase-8 activation. The C-terminus of BaxΔ2 has...
Show moreBaxΔ2 is an isoform of the proapoptotic Bcl-2 family member Bax that promotes cell death via caspase-8 activation. The C-terminus of BaxΔ2 has been shown to be crucial for caspase-8 dependent cell death in colon cancer cells. However, it is unknown whether the C-terminal primary sequence or secondary structure is necessary for interaction with caspase-8. In this project, several BaxΔ2 C-terminal mutants were generated based on secondary structure predictions. Models showed that mutating Leu164 and Thr165 to Ala (LT-AA) would increase the probability of alpha helix formation, while mutating Leu164 to Pro (L-P) would decrease the probability of alpha helix formation. Expression of these mutant proteins in colon cancer HCT116 cells, showed that L164P, and not L164A/T165A, significantly impaired BaxΔ2 function. The mutant L164P proteins formed atypical aggregates, and their ability to induce cell death was also significantly decreased when compared to the wild type. These results indicate that the BaxΔ2 C-terminal tridimensional structure, and not the specific primary sequence, is critical for triggering aggregation-mediated cell death.
M.S. in Biology, May 2018
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Title: GENETIC MODIFICATION OF PAENIBACILLUS UTILIZING VITREOSCILLA HEMOGLOBIN TO IMPROVE BIODESULFURIZATION
Creator: Bai, Yu
Date: 2015, 2015-05
Description: Biodesulfurization (BDS) is a type of microbial biodegradation involving the removal of organic sulfur compounds from fossil fuels that is...
Show moreBiodesulfurization (BDS) is a type of microbial biodegradation involving the removal of organic sulfur compounds from fossil fuels that is accomplished by utilizing the metabolism of certain microorganisms (McFarland et al., 1999). In past decades, many related genetic modifications or transformations have been made to improve biodesulfurization. In this study, Vitreoscilla hemoglobin (VHb) was used to enhance the ability of sulfur metabolism and growth in Paenibacillus naphthalenovorans. Paenibacillus naphthalenovorans wild type (32O-Y) is a thermophilic bacterium isolated in our lab that has also been transformed with recombinant plasmid pnW33N-vgb (producing strain 32O-Y[pNW33N-vgb]). This plasmid encodes both VHb and chloramphenicol (Chl) resistance. The Chl resistance gene provides a method to distinguish from wild type and select for transformed 32O-Y[pNW33N-vgb]. Presence of the plasmid in the transformed strain was verified utilizing PCR. Both 32O-Y and 32O-Y[pNW33N vgb] grew in minimal medium (CDM) that contained dibenzothiophene (DBT) as the sole sulfur source (while Chl was added to 32O-Y[pNW33N-vgb] cultures). DBT is a common organic sulfur-containing molecule in petroleum. It is metabolized by the dsz pathway, present in a number of soil bacteria, which produces 2-hydroxybiphenol (2-HBP) as the final product. Growth (OD600mm) of 32O-Y and 32O-Y[pNW33N-vgb] at 37°C, 45°C, 50°C were compared. The desulfurization activities of wild type and transformed Paenibacillus naphthalenovorans strains were monitored by the Gibbs assay, which measures the concentration of 2-HBP through absorbance at 610 nm. The results demonstrate that the expression of VHb in strain 32O-Y[pNW33N-vgb] correlated with increased growth, especially at 37°C. The desulfurization activities of 32O-Y[pNW33N-vgb] at various temperatures were also improved, compared to untransformed 32O-Y, as VHb was expressed. Efficiency of the VHb-related improvements at the three temperatures was calculated as the ratio between maximum 2-HBP produced and OD600nm at this point. The efficiency values indicated that when compared to 32O-Y, 32O-Y[pNW33N-vgb] had maximum increased productivity at 37°C and 50°C, and minimum at 45°C.
M.S. in Biology, May 2015
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Title: DESIGN AND FABRICATION OF AN UNMANNED GROUND VEHICLE UTILIZING VARIABLE INTERNAL INERTIAL PROPERTIES
Creator: Ruffatto Iii, Donald
Date: 2011-11-27, 2011-12
Description: Mobility of an Unmanned Ground Vehicle (UGV) is highly dependent upon the maximum lateral and longitudinal forces that can be generated at the...
Show moreMobility of an Unmanned Ground Vehicle (UGV) is highly dependent upon the maximum lateral and longitudinal forces that can be generated at the tire/ground interface. These forces are a function of a number of di erent vehicle properties such as suspension geometry, actuators and the tire/terrain interaction mechanics. Typically these properties are xed imposing general limits to the vehicle's maximum achievable lateral and longitudinal accelerations. If you were instead able to modify these parameters dynamically during vehicle operation substantial improvements in robot mobility can be realized. This thesis presents the design a fabrication of the Variable Inertial Vehicle (VIV) which is capable of realizing this. It uses a shifting mass mechanism to vary the normal load distribution among the front and rear tire based upon the desired operating conditions. The shifting mass mechanism is capable of moving a substantial amount of the vehicle along it longitudinally. This provides direction control of the tire normal forces during operation. Described in this thesis is the design of this unique element and its e ects on the rest of the vehicle design. The other main elements di erentiating the VIV from common UGV's such as the electronics, suspension, chassis, and powertrain are also detailed. Finally, a number of experiments utilizing the VIV are presented. These experiments were devised and performed my Chenghui Nie but are presented here to demonstrate the functionality and capabilities of the VIV.
M.S. in Mechanical Engineering, December 2011
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