Engineering Commons^™

Multi-Carrier Radar For Target Detection And Communications, John David Ellinger

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This dissertation considers the optimization of radar performance within the structure imposed by a coded Orthogonal Frequency Division Multiplexing (OFDM) format required to achieve an acceptable communication link. The dual goal of achieving both satisfactory radar and communication performance raises challenges that can be substantively addressed by combining phase coding and modulation techniques to provide the temporal and spectral structure necessary to implement simultaneous radar and communication operations. In particular, the specific techniques, as introduced within this dissertation, of using the Multi-Frequency Complementary Phase Coded (MCPC) sequences, as prescribed by Levanon and Mozeson, for simultaneous radar and wireless communication operations …

The Effect Of Laser Power And Scan Speed On Melt Pool Characteristics Of Pure Titanium And Ti-6al-4v Alloy For Selective Laser Melting, Chandrakanth Kusuma

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Selective Laser Melting (SLM) is an additive manufacturing (AM) technique that creates complex parts by selectively melting metal powder layer-by-layer. In SLM, the process parameters decide the quality of the fabricated component. In this study, single beads of commercially pure titanium (CP-Ti) and Ti-6Al-4V alloy are melted on a substrate of the same material as powder using an in-house built SLM machine. Multiple combinations of laser power and scan speed are used for single bead fabrication while the laser beam diameter and powder layer thickness are kept constant. This experimental study investigates the influence of laser power, scan speed and …

Knowledge-Empowered Probabilistic Graphical Models For Physical-Cyber-Social Systems, Pramod Anantharam

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There is a rapid intertwining of sensors and mobile devices into the fabric of our lives. This has resulted in unprecedented growth in the number of observations from the physical and social worlds reported in the cyber world. Sensing and computational components embedded in the physical world constitute a Cyber-Physical System (CPS). Current science of CPS is yet to effectively integrate citizen observations in CPS analysis. We demonstrate the role of citizen observations in CPS and propose a novel approach to perform a holistic analysis of machine and citizen sensor observations. Specifically, we demonstrate the complementary, corroborative, and timely aspects …

Fault Diagnosis And Fault-Tolerant Control Of Quadrotor Uavs, Remus C. Avram

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Quadrotors represent a special class of Unmanned Aerial Vehicles (UAVs) and have attracted significant attention in recent years due to their potential in various military and civilian applications. However, due to their intrinsic fabrication process and component damage, quadrotors are prone to various type of faults. This dissertation presents the design, analysis, and experimental implementation of fault diagnosis, fault-tolerant control, and controller verification methods to achieve safety assurance and trusted autonomy of quadrotor UAVs. First, the issue of sensor faults is investigated under two different scenarios: (1) the case when all Euler angles are available for measurement; (2) the case …

Design And Evaluation Of A Fiber Optic Shape Tracker For Use As A Navigational Aid In Endovascular Guidewires And Catheters, Benjamin Stewart Rinehart

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Endovascular intervention is the current gold-standard for screening and treating aortic aneurysms and complications caused by peripheral vascular disease (PAD). A typical endovascular procedure begins with inserting an endovascular guidewire into the femoral artery via incision. A catheter is then threaded over the guidewire and both tools are then navigated to the treatment site. The navigation is guided solely by fluoroscopy (x-ray) imagery that is performed throughout the duration of the procedure. Not only does this method provide limited 2-D guidance, but also exposes the patient and medical staff to high levels of radiation. This thesis research focuses on the …

Fpga Realization Of Low Register Systolic All One-Polynomial Multipliers Over Gf (2M) And Their Applications In Trinomial Multipliers, Pingxiuqi Chen

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All-one-polynomial (AOP)-based systolic multipliers over GF (2m) are usually not con-sidered for practical implementation of cryptosystems such as elliptic curve cryptography (ECC) due to security reasons. Besides that, systolic AOP multipliers usually suer from the problem of high register-complexity, especially in field-programmable gate array (FPGA) platforms where the register resources are not that abundant. In this thesis, however, we have shown that the AOP-based systolic multipliers can easily achieve low register-complexity implementations and the proposed architectures can be employed as computation cores to derive ecient implementations of systolic Montgomery multipli-ers based on trinomials, which are recommended by the National Institute …

A Theoretical Framework For Evaluating Mental Workload Resources In Human Systems Design For Manufacturing Operations, Sharon Claxton Bommer

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Manufacturing is a human-driven process that applies energy and manpower to produce consumer goods. In repetitive task processes like manufacturing systems, optimal performance is extremely important for the production employee and the company. In the general fast pace of manufacturing operations, there is the potential for operator errors, which correlates to possible safety issues and loss of revenue. This research explores the influence of cognitive resources on operator performance in manufacturing operations using the Multiple Resource Theory (MRT) and mental workload measures. Computer simulation models and mathematical modeling with Improved Performance Research Integration Tool (IMPRINT) were used to assess mental …

Growth And Characterization Of Molybdenum Disulfide Thin Films, Carl Morris Gross Iii

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Two-dimensional materials, or materials that are only one atomic layer thick, have seen much research in recent years because of their interesting electrical properties. The first of these materials, graphene, was found to have incredible electrical properties but lacked a bandgap in intrinsic films. Without a bandgap, graphene cannot create transistors that can be shut off. Molybdenum disulfide, however, is a two-dimensional semiconductor with a large bandgap. The main issue of molybdenum disulfide is that synthesized films are a much lower quality than their exfoliated counterparts. For molybdenum disulfide to be able to be used practically, a method of synthesis …

Performance Prediction Of Constrained Waveform Design For Adaptive Radar, Aaron M. Jones

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Today's radars face an ever increasingly complex operational environment, intensified by the numerous types of mission/modes, number and type of targets, non-homogenous clutter and active interferers in the scene. Thus, the ability to adapt ones transmit waveform, to optimally suit the needs for a particular radar tasking and environment, becomes mandatory. This requirement brings with it a host of challenges to implement including the basic decision of what to transmit. In this dissertation, we discuss six original contributions, including the development of performance prediction models for constrained radar waveforms, that aid in the decision making process of an adaptive radar …

Refining A Post-Stroke Pharmacological And Physical Treatment To Reduce Infarct Volume Or Improve Functional Recovery, Using Gene Expression Changes In The Peri-Infarct Region To Examine Potential Mechanisms In Male And Female Rats, Moner A. Ragas

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Stroke, a life-threatening medical condition, is the fifth-leading cause of death in the United States with an estimated annual cost of treatments above $70 billion. A combination of innovative approaches was used in our lab to optimize the pre-clinical stroke research design by choosing the most appropriate animal model and methodologies to increase the translational capability of the stroke research. The first study, modeled after ongoing clinical trials using fluoxetine, refined the appropriate timing of fluoxetine and ascorbic acid delivery if a rat was on simvastatin for 7 days pre-stroke and throughout the remainder of the study. Administration of fluoxetine …

Co-Transplantation Of Endothelial Progenitor Cells And Neural Progenitor Cells For Treating Ischemic Stroke In A Mouse Model, Jinju Wang

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Ischemic stroke (IS) is a major cause of death and disability with limited and less effective therapeutics. Transplantation of stem cells, such as neuronal progenitor cells (NPCs) and endothelial progenitor cells (EPCs), is promising for treating IS. It is well known that neurogenesis and angiogenesis are critical for cerebral repair following ischemic injury. However, whether co-transplantation of EPCs and NPCs has synergistic effects remains unclarified. In addition, the PI3K/Akt pathway participates in modulating a widely range of cellular functions such as anti-apoptotic and anti-oxidant. The signal pathways responsible for the effects of grafted NPCs and EPCs are also waiting for …

Modular Multi-Signal Tracking Pulse Descriptor Word (Pdw) Generator With Field Programmable Gate Array (Fpga) Implementation, Justin Darrell Pelan

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As signal spectra become dense, the task of tracking and identifying radars becomes increasingly cumbersome. The variety of radars in modern theaters of war compound the task due to simultaneous operation. Real-time processing of large data sets prove difficult for sequential systems, and the parallelism of Field Programmable Gate Arrays (FPGAs) becomes an attractive option. To mitigate the increasing complexity of this task, this design proposes an FPGA architecture to produce pulse descriptor words (PDW) for up to eight independent radio frequency signals that can be used in near-real-time processing. Focusing on digital hardware techniques and modular design allow for …

Knowledge-Driven Implicit Information Extraction, Pathirage Dinindu Perera

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Natural language is a powerful tool developed by humans over hundreds of thousands of years. The extensive usage, flexibility of the language, creativity of the human beings, and social, cultural, and economic changes that have taken place in daily life have added new constructs, styles, and features to the language. One such feature of the language is its ability to express ideas, opinions, and facts in an implicit manner. This is a feature that is used extensively in day to day communications in situations such as: 1) expressing sarcasm, 2) when trying to recall forgotten things, 3) when required to …

Probabilistic Svm For Open Set Automatic Target Recognition On High Range Resolution Radar Data, Jason Daniel Roos

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The application of Automatic Target Recognition (ATR) on High Range Resolution (HRR) radar data in a scenario that contains unknown targets is of great interest for military and civilian applications. HRR radar data provides greater resolution of a target as well as the ability to perform ATR on a moving target, which gives it an advantage over other imaging systems. With the added resolution of HRR comes the disadvantage that a change in the aspect angle or orientation results in greater changes in the collected data, making classical ATR more difficult. Closed set ATR on HRR radar data is defined …

A Statistical Approach To Broadband Noise Suppression, Walter Eversman

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A method for estimating achievable attenuation for broadband noise in an inlet duct, consistent with Dyer's suggestion that an appropriate model includes all propagating acoustic modes at equal power and random phase, is proposed. Broadband noise is represented in a frequency domain analysis by a statistical distribution of propagating duct modes. The required number of modes is estimated by Rice's approximation method and verified in FEM modeling. For each propagating circumferential mode propagating radial modes have equal acoustic power and random phase. Source acoustic power is distributed among circumferential modes according to the number of propagating radial modes in the …

Decomposition Of A Double Salt Ionic Liquid Monopropellant On Heated Metallic Surfaces, Steven P. Berg, Joshua L. Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A monopropellant consisting of 59% hydroxylammonium nitrate and 41% 1-ethyl-3-methylimidazolium ethyl sulfate by mass is tested for decomposition on heated platinum, rhenium, and titanium surfaces. It was found that the propellant decomposes at 165 °C on titanium, which is the decomposition temperature of HAN. The onset temperature for decomposition on platinum was 85 °C and on rhenium it was 125 °C. This suggests that platinum and rhenium act as catalysts for the decomposition of the monopropellant. From the experimental data, Arrhenius-type reaction rate parameters were calculated. The activation energy for platinum was 3 times less than that of titanium suggesting …

Fluorescent Nanocomposite Of Embedded Ceria Nanoparticles In Crosslinked Pva Electrospun Nanofibers, Nader Shehata, Soha Gaballah, Effat Samir, Aya Hamed, Marwa Saad

Biology Faculty Publications

This paper introduces a new fluorescent nanocomposite of electrospun biodegradable nanofibers embedded with optical nanoparticles. In detail, this work introduces the fluorescence properties of PVA nanofibers generated by the electrospinning technique with embedded cerium oxide (ceria) nanoparticles. Under near-ultra violet excitation, the synthesized nanocomposite generates a visible fluorescent emission at 520 nm, varying its intensity peak according to the concentration of in situ embedded ceria nanoparticles. This is due to the fact that the embedded ceria nanoparticles have optical tri-valiant cerium ions, associated with formed oxygen vacancies, with a direct allowed bandgap around 3.5 eV. In addition, the impact of …

Nx 10 For Engineering Design -- Learning Edition, Ming-Chuan Leu, Amir Ghazanfari, Krishna C. R. Kolan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

NX is one of the world’s most advanced and tightly integrated CAD/CAM/CAE product development solution. Spanning the entire range of product development, NX delivers immense value to enterprises of all sizes. It simplifies complex product designs, thus speeding up the process of introducing products to the market.

The NX software integrates knowledge-based principles, industrial design, geometric modeling, advanced analysis, graphic simulation, and concurrent engineering. The software has powerful hybrid modeling capabilities by integrating constraint-based feature modeling and explicit geometric modeling. In addition to modeling standard geometry parts, it allows the user to design complex free-form shapes such as airfoils and …

An Introduction To The Special Issue On Geoscience Papers Of The Future, Cédric H. David, Yolanda Gil, Christopher J. Duffy, Scott D. Peckham, S. Karan Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Advocates of enhanced quality for published scientific results are increasingly voicing the need for further transparency of data and software for scientific reproducibility. However, such advanced digital scholarship can appear perplexing to geoscientists that are seduced by the concept of open science yet wonder about the exact mechanics and implications of the associated efforts. This special issue of Earth and Space Science entitled "Geoscience Papers of the Future" includes a review of existing best practices for digital scholarship and bundles a set of example articles that share their digital research products and reflect on the process of opening their scientific …

A Biomechanical Comparison Between Expert And Novice Manual Materials Handlers Using A Multi-Joint Emg-Assisted Optimization Musculoskeletal Model Of The Lumbar Spine, Denis Gagnon, André Plamondon, Christian Larivière

Études primaires

Expertise is a key factor modulating the risk of low back disorders (LBD). Through years of practice in the workplace, the typical expert acquires high level specific skills and maintains a clean record of work-related injuries. Ergonomic observations of manual materials handling (MMH) tasks show that expert techniques differ from those of novices, leading to the idea that expert techniques are safer. Biomechanical studies of MMH tasks performed by experts/novices report mixed results for kinematic/kinetic variables, evoking potential internal effect of expertise. In the context of series of box transfers simulated by actual workers, detailed internal loads predicted by a …

Subject-Specific Biomechanics Of Trunk: Musculoskeletal Scaling, Internal Loads And Intradiscal Pressure Estimation, F. Ghezelbash, A. Shirazi-Adl, N. Arjmand, Z. El-Ouaaid, A. Plamondon

Études primaires

Development of a subject-specific computational musculoskeletal trunk model (accounting for age, sex, body weight and body height), estimation of muscle forces and internal loads as well as subsequent validation by comparison with measured intradiscal pressure in various lifting tasks are novel, important and challenging. The objective of the present study is twofold. First, it aims to update and personalize the passive and active structures in an existing musculoskeletal kinematics-driven finite element model. The scaling scheme used an existing imaging database and biomechanical principles to adjust muscle geometries/cross-sectional-areas and passive joint geometry/properties in accordance with subjects’ sex, age, body weight and …

Review Of Sensing Methodologies For Estimation Of Combustion Metrics, Libin Jia, Jeffrey D. Naber, Jason R. Blough

Michigan Tech Publications, Part 1

For reduction of engine-out emissions and improvement of fuel economy, closed-loop control of the combustion process has been explored and documented by many researchers. In the closed-loop control, the engine control parameters are optimized according to the estimated instantaneous combustion metrics provided by the combustion sensing process. Combustion sensing process is primarily composed of two aspects: combustion response signal acquisition and response signal processing. As a number of different signals have been employed as the response signal and the signal processing techniques can be different, this paper did a review work concerning the two aspects: combustion response signals and signal …

Direct Position Control Of Dielectric Barrier Discharge Filaments, Matthew C. Paliwoda, Joshua L. Rovey, Mitchell Wainwright

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Controllable patterns of plasma filaments are being explored for reconfigurable metamaterial applications. When operated in a filamentary mode, volume dielectric barrier discharges are known to produce patterns of self-organizing plasma filaments. In this work the presence and intensity of a single filament at a fixed location is controlled by an isolated and independently electrically adjusted needle electrode. Time-averaged normalized light intensity, current, and voltage are measured while varying the voltage of the needle through a self-biasing resistance. For a 7.5 kV, 3.2 kHz DBD, the needle-controlled filament discharges similar to adjacent filaments at low potentials but stops discharging at a …

A Clean Electricity Future: Assessing The Role Of Wide-Area Power System Operations In Supporting Weather-Driven Renewable Energy In The U.S., Paul D. Picciano

Pomona Senior Theses

Over the coming decades, renewable energy sources, namely wind and solar, will need to play a larger role in our nation’s energy mix as we seek to lower greenhouse emissions and respond to renewable energy policies and the EPA’s Clean Power Plan. This thesis assesses the role of wider-area power system operations in the U.S. as a powerful solution in supporting the integration of these weather-driven, variable energy resources that pose substantial challenges to grid reliability. The expansion and integration of organized electricity markets and transmission networks over wider geographic areas can (1) help reduce net-variability in wind and solar …

Analysis Of Pellet Cladding Interaction And Creep Of U3si2 Fuel For Use In Light Water Reactors, Kathryn E. Metzger

Theses and Dissertations

Following the accident at the Fukushima plant, enhancing the accident tolerance of the light water reactor (LWR) fleet became a topic of serious discussion. Under the direction of congress, the DOE office of Nuclear Energy added accident tolerant fuel development as a primary component to the existing Advanced Fuels Program. The DOE defines accident tolerant fuels as fuels that “in comparison with the standard UO2- Zircaloy system currently used by the nuclear industry, can tolerate loss of active cooling in the reactor core for a considerably longer time period (depending on the LWR system and accident scenario) while maintaining or …

A Lithium Battery Current Estimation Technique Using An Unknown Input Observer, Daniel Cambron

Theses and Dissertations--Electrical and Computer Engineering

Current consumption measurements are useful in a wide variety of applications, including power monitoring and fault detection within a lithium battery management system (BMS). This measurement is typically taken using either a shunt resistor or a Hall-effect current transducer. Although both methods have achieved accurate current measurements, shunt resistors have inherent power loss and often require isolation circuitry, and Hall-effect sensors are generally expensive. This work explores a novel alternative to sensing battery current by measuring terminal voltages and cell temperatures and using an unknown input observer (UIO) to estimate the battery current. An accurate model of a LiFePO_{4 …}

Modelling Of The Nanowire Cds-Cdte Device Design For Enhanced Quantum Efficiency In Window-Absorber Type Solar Cells, Rasika Ganvir

Theses and Dissertations--Electrical and Computer Engineering

Numerical simulations of current-voltage characteristics of nanowire CdS/CdTe solar cells are performed as a function of temperature using SCAPS-1D. This research compares the experimental current-voltage (I-V) characteristics with the numerical (I-V) simulations obtained from SCAPS-1D at various temperatures. Various device parameters were studied which can affect the efficiency of the nanowire-CdS/CdTe solar cell. It was observed that the present simulated model explains the important effects of these solar cell devices, such as the crossover and the rollover effect. It was shown that the removal of defect in i-SnO2 is responsible for producing the crossover effect. In the past, the rollover …

A Modular Electrical Power System Architecture For Small Spacecraft, Timothy M. Lim

Theses and Dissertations--Electrical and Computer Engineering

Small satellites and CubeSats have established themselves within the aerospace community because of their low cost and high return on investment. Many CubeSats are developed in a short time frame and often leverage commercial off the shelf components for quick turnaround missions. With regard to the Electrical Power System, commercially available products typically use a centralized architecture. However, a centralized architecture is not reusable, since missions that require additional solar arrays or batteries would necessitate a redesign of the power system. With the range of CubeSat sizes and mission goals, it is obvious that a one-size-fits-all solution is not appropriate. …

Analysis Of Vocal Fold Kinematics Using High Speed Video, Harikrishnan Unnikrishnan

Theses and Dissertations--Electrical and Computer Engineering

Vocal folds are the twin in-folding of the mucous membrane stretched horizontally across the larynx. They vibrate modulating the constant air flow initiated from the lungs. The pulsating pressure wave blowing through the glottis is thus the source for voiced speech production. Study of vocal fold dynamics during voicing are critical for the treatment of voice pathologies. Since the vocal folds move at 100 - 350 cycles per second, their visual inspection is currently done by strobosocopy which merges information from multiple cycles to present an apparent motion. High Speed Digital Laryngeal Imaging(HSDLI) with a temporal resolution of up to …

Robust Background Subtraction For Moving Cameras And Their Applications In Ego-Vision Systems, Hasan Sajid

Theses and Dissertations--Electrical and Computer Engineering

Background subtraction is the algorithmic process that segments out the region of interest often known as foreground from the background. Extensive literature and numerous algorithms exist in this domain, but most research have focused on videos captured by static cameras. The proliferation of portable platforms equipped with cameras has resulted in a large amount of video data being generated from moving cameras. This motivates the need for foundational algorithms for foreground/background segmentation in videos from moving cameras. In this dissertation, I propose three new types of background subtraction algorithms for moving cameras based on appearance, motion, and a combination of …