Engineering Commons^™

Evaluation Of Functional Near Infrared Spectroscopy (Fnirs) For Assessment Of The Visual And Motor Cortices In Adults, Brenna Giacherio

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Introduction: Functional near-infrared spectroscopy (fNIRS) is a relatively young technique in the field of medical imaging. As such, it has yet to be widely implemented for clinical use, despite its promising advantages. However, unlike fMRI-its much bulkier and costly counterpart-fNIRS has yet to be proven as a standalone imaging tool within a clinical setting, particularly that of ophthalmology or physical therapy.

Methods: Ten healthy young adults (23.8 ± 4.8 years) participated in the study. Activation of the visual cortex was achieved utilizing various reversing checkerboard stimuli across three data collection sessions for each participant. Further, activation of the motor cortex …

Fatigue Based Structural Design Exploration Via Engineering Data Analytics, Hao Li

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In manufacturing industry, a successful machine development requires the durability of structure components to meet fatigue life targets. The typical way to obtain fatigue design loads for conceptual design exploration is based on hand calculations or historical data to capture envelopes of expected system responses, which may not guarantee to capture actual damaging loads. In this study, a new approach is developed to extract a fatigue design load set directly from measured load data for a conceptual design exploration. The proposed framework integrates the techniques from data analytics and physics based engineering mechanics to amplify and detect fundamental damaging load …

Combating Integrity Attacks In Industrial Control Systems, Chad Arnold

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Industrial Control Systems are vulnerable to integrity attacks because of connectivity to the external Internet and trusted internal networking components that can become compromised. Integrity attacks can be modeled, analyzed, and sometimes remedied by exploiting properties of physical devices and reasoning about the trust worthiness of ICS communication components.

Industrial control systems (ICS) monitor and control the processes of public utility that society depends on - the electric power grid, oil and gas pipelines, transportation, and water facilities. Attacks that impact the operations of these critical assets could have devastating consequences. The complexity and desire to interconnect ICS components have …

Non-Equilibrium Models For High Temperature Gas Flows, Daniil Andrienko

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A multi-physical approach is developed for non-equilibrium high enthalpy flows to cover a wide range of interdisciplinary studies. Compressible Navier-Stokes equations are coupled with the chemical model and equation of energy conservation for internal degrees of freedom. The model is capable of accounting for the non-equilibrium dissociation and thermal radiation heat transfer in gas flows. The methodology covers a range of problems from the combustion in subsonic counter-flowing jets to the hypersonic re-entry flows. The present approach attempts to validate the finite rate chemistry mechanisms by modeling the diffusive non-premixed flame of hydrogen at a very low Mach number. The …

A Novel Synergistic Model Fusing Electroencephalography And Functional Magnetic Resonance Imaging For Modeling Brain Activities, Konstantinos Michalopoulos

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Study of the human brain is an important and very active area of research. Unraveling the way the human brain works would allow us to better understand, predict and prevent brain related diseases that affect a significant part of the population. Studying the brain response to certain input stimuli can help us determine the involved brain areas and understand the mechanisms that characterize behavioral and psychological traits.

In this research work two methods used for the monitoring of brain activities, Electroencephalography (EEG) and functional Magnetic Resonance (fMRI) have been studied for their fusion, in an attempt to bridge together the …

Improving Learning Outcomes In Ee2010l Using Ni Mydaq In An Inverted Lab, Ryan F.A. Hamilton

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E 2010L Circuit Analysis Lab is an introductory course in analog circuits for students majoring in Electrical Engineering, Engineering Physics, Mechanical Engineering, Materials Science, and Computer Engineering at Wright State University. Prior to conversion to the semester calendar, from the quarter calendar, the course was known as EE 302 Circuit Analysis I Lab. In the terms since the semester conversion it has been noticed the percentage of students receiving grades of D (poor), F (failed), W (withdrawn), K (withdrawal in first two weeks), or X (unofficial withdrawal) has increased from the rate in the previous iteration of the course

. …

Rab3a As A Modulator Of Homeostatic Synaptic Plasticity, Andrew G. Koesters

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The nervous system is faced with perturbations in activity levels throughout development and in disease or injury states. Neurons need to adapt to these changes in activity, but also need to maintain circuit firing within a normal range to stabilize the network from becoming too excited or too depressed. Homeostatic synaptic plasticity, the compensatory increase or decrease in synaptic strength as a result of excessive circuit inhibition or excitation, is a mechanism that the nervous system utilizes to keep network activity at normal levels. Despite intense effort, little is known about the mechanisms underlying homeostatic synaptic plasticity. Numerous studies have …

Biaxial Material Design Method For The Reduced Aperture Waveguide Model, Jason M. Brand

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The design and characterization of metamaterials has emerged as a field of great interest in electromagnetics in recent years. The characterization has been accomplished primarily by means of fabrication, measurement, and parameter estimation. Previous work by Knisely and Havrilla [8] has shown that biaxial anisotropy can be created by machining air vias uniaxially into a homogeneous, isotropic material. This research project proposes a design method for manufactured biaxial materials. Full wave modeling and simulation is used for samples with varying via size, separation and pose to obtain the scattering parameters S11 and S21. To compare the simulated S-parameters to theoretical …

Automated Complexity-Sensitive Image Fusion, Brian Patrick Jackson

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To construct a complete representation of a scene with environmental obstacles such as fog, smoke, darkness, or textural homogeneity, multisensor video streams captured in diferent modalities are considered. A computational method for automatically fusing multimodal image streams into a highly informative and unified stream is proposed. The method consists of the following steps: 1. Image registration is performed to align video frames in the visible band over time, adapting to the nonplanarity of the scene by automatically subdividing the image domain into regions approximating planar patches

2. Wavelet coefficients are computed for each of the input frames in each modality …

Stochastic Modeling Of Geometric Mistuning And Application To Fleet Response Prediction, Emily Brooke Henry

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An improved spatial statistical approach and probabilistic prediction method for mistuned integrally bladed rotors is proposed and validated with a large population of rotors. Prior work utilized blade-alone principal component analysis to model spatial variation arising from geometric deviations contributing to forced response mistuning amplification. Often, these studies considered a single rotor measured by contact probe coordinate measurement machines to assess the predictive capabilities of spatial statistics through principal component analysis. The validity of the approach has not yet been demonstrated on a large population of mistuned rotors representative of operating fleets, a shortcoming addressed in this work. Furthermore, this …

Adapting Linguistic Deception Cues For Malware Detection, Stacie Noel Severyn

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People verbally express themselves in a variety of ways, yet the same patterns consistently appear within the words of a person who is being deceptive. This research provides insight and demonstrates that similar patterns exist within malicious software that do not commonly exist within benign software, and can be used to help determine that the software is malicious or untrustworthy.

The patterns that have been shown to exist within deceptive language were investigated to determine whether similar patterns exist within malware. Tests were performed to determine whether malware is more likely to consistently contain a higher or lower frequency of …

Adaptive I/Q Mismatch Compensation For Wideband Receiver, Linda Zhu

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Wide working bandwidth is one of the main concerns in digital wideband receiver. The traditional digital receiver covers only one Nyquist zone, which bandwidth range is from DC to half of the sampling frequency. By utilizing in-phase/quadrature (I/Q) channels, wideband receiver is able to double the working bandwidth, which covers from DC to half of the sampling frequency and also from negative half of the sampling frequency to DC. However, I/Q mismatch in reality introduces unwanted signals, which significantly reduce the system performance and the quality of the received signals. In this thesis, an adaptive I/Q mismatch compensation technique is …

Segmentation And Analysis Of Mris Of Infants With Dysphagia, Irfaan A. Dar

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Neonates are at a rapid stage of development from birth throughout childhood. Impairments to certain cortical areas can result in long lasting neuro-cognitive dysfunctions. Disorders to the swallowing neural pathways can have detrimental effects throughout life course since methods to provide nutrition can be comprised. Dysphagia, or the inability to swallow, can be caused by a multitude of reasons, chiefly neurological, but the underlying disruptions to the neural pathways are not defined. In this study we investigated the growth of multiple cortical areas involved in the swallowing pathway and categorized feeding outcomes with neural growth. Results showed that infants that …

Dynamic Repeater With Booster Enhancement For Fast Switching Speed And Propagation In Long Interconnect, Kaushik Reddy Katpally

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A System-on-a-Chip (SoC) has millions of transistors connected by wires or so called Interconnects. As CMOS technologies scale down, SoC becomes more complex and denser. The delays of basic cells decrease, hereby improving logic gate and logic block delay. However, long wires connecting logic blocks still contribute significant delays, which limit SoC's speed performance.

In this thesis, we take a practical approach towards reducing propagation delay in long wire (Interconnect). A dynamic repeater with Booster enhancement circuit is presented and analyzed in this regard. Both switching speed and Interconnect propagation delay are significantly improved upon locally enabling the Booster to …

Finite Element Simulation Of Skull Fracture Evoked By Fall Injuries, Anthony Vicini

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This study presents novel predictive equations for von Mises stresses and deflection of bones in the frontal and lateral regions of the skull. The equations were developed based on results of a finite element model developed here. The model was validated for frontal and lateral loading conditions with input values mimetic to fall scenarios. Using neural network processing of the information derived from the model achieved R2 values of 0.9990 for both the stress and deflection. Based on the outcome of the fall victims, a threshold von Mises stress of 40.9 to 46.6 MPa was found to indicate skull fracture …

Use Of Vibrotactile Feedback And Stochastic Resonance For Improving Laparoscopic Surgery Performance, Robert Douglas Hoskins

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Vibrotactile feedback, used as sensory substitution for loss of haptic feedback, has been utilized to improve performance in manual control, teleoperation and during minimally invasive surgical tasks. Stochastic resonance (SR), introduced into the human control system as white noise at a sub-threshold level, has shown promise to improve the sensitivity of tactile receptors resulting in enhancement of performance for a variety of manual tracking and sensorimotor tasks. The purpose of this study was to determine if SR could improve performance (accuracy, speed) in a simulated laparoscopic palpation task and to compare it to vibrotactile feedback (VIB). It was hypothesized that …

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Design Of Thermal Structures Using Topology Optimization, Joshua D. Deaton

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The design of structures subjected to elevated temperature environments has long been an important area of study in the aerospace industry. This is especially true in the modern day, where new problems related to embedded engine aircraft and high temperature exhaust-washed structures present new structural design challenges not found in past applications. In this work, the response of a class of thermal structures whose responses are characterized by significant amounts of restrained expansion, to which exhaust-washed structures belong, are studied. To address the complex design challenges that become evident in these investigations, structural topology optimization is applied due to its …

Development Of The Academic Performance-Commitment Matrix (Apcm): Understanding The Effects Of Motivation And An Engineering Mathematics Curricular Intervention On Student Self-Efficacy And Success In Engineering, Anthony Bourne

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The latest push to encourage workforce growth in science, technology, engineering and math (STEM) disciplines has generated varying results. Overall, demand for STEM graduates is outpacing the numbers available. This has motivated a wide range of proposed solutions to increase the number of people trained to work in these fields. While a focus on college recruitment in these areas is a necessity for increasing numbers of STEM graduates, the expanding variety of students admitted to university programs in STEM disciplines creates a new series of issues in higher education. Most prominently, retention and graduation rates are low in STEM disciplines. …

An Experimental Investigation On The Micro Air Vehicle, Shih Kang Huang

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An experimental investigation was conducted to study the flow characteristics of the flow around the flapping wings of a four-wing flapper as well as the lift and thrust coefficient of a four-wing flapper. In the present study, a clap-and-fling type of four-wing flapper was designed and manufactured by using several flexible materials, such as PET film, latex, and aluminized Mylar. Different cross-strut patterns and dimensions of wings were manufactured and tested to optimize the wing designs. In addition to taking the lift and thrust measurements using a highly sensitive force moment sensor unit, a high-resolution Particle Image Velocimetry (PIV) system …

Improving Motion Imagery Analysis: Investigating Detection Failures, Remembering To Perform Deferred Intentions, Michael R. Nickels

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Advances in automation have led to an increased prevalence of human multitasking in intelligence, surveillance, and reconnaissance operations. Despite advancements in computer-vision research, almost all video data collected must be processed by human analysts. Traditionally, analysts are plagued with the presence and possible overabundance of interruptions that fundamentally leads to multitasking while processing video data. It is currently unknown what factors influence decision making in completing primary tasks or handling interruptions. In this study, we investigated the performance effects and the resulting design implications of varying the number of concurrent prospective memory tasks and encoding of one large group of …

The Properties Of Property Alignment On The Semantic Web, Michelle Andreen Cheatham

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Ontology alignment is an important step in enabling computers to query and reason across the many linked datasets on the semantic web. This is a difficult challenge because the ontologies underlying different linked datasets can vary in terms of subject area coverage, level of abstraction, ontology modeling philosophy, and even language. The alignment approach presented here centers on string similarity metrics. Nearly all ontology alignment systems use a string similarity metric in one form or another, but it seems that the choice of a particular metric is often arbitrary. We begin this dissertation with the most comprehensive survey to date …

16-Bit Digital Adder Design In 250nm And 64-Bit Digital Comparator Design In 90nm Cmos Technologies, Naga Venkata Vijaya Krishna Boppana

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High speed, low power, and area efficient adders and comparators continue to play a key role in hardware implementation of digital signal processing applications. Adders based on Complimentary Pass Transistor Logic (CPL) are power and area efficient, but are slower compared to Square Root Carry Select (SQRT-CS) based adders. This thesis demonstrates a unique custom designed 16-bit adder in 250-nm CMOS technology to obtain fast and power/area efficient features by combining CPL and CS logic. Comparing the results obtained for proposed 16-bit Linear CPL/CS adder with the BEC (Binary Excess-1 Code) based low power SQRT-CS adder, the delay is reduced …

Pixel Qualification Methods In Attributed Scattering Center Extraction, Justin Tyler Farmer

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Recent work with the spectrum-parted linked image test (SPLIT) uses polarization with Fourier-based peak detection to qualify pixels for attributed scattering center (ASC) extraction from synthetic aperture radar (SAR) phase history data. SPLIT is a two-stage, non-linear technique to extract ASCs. The first stage qualifies pixels for ASC attribution, but suffers from imaging sidelobe energy. Error in pixel qualification propagates to stage two: pixel attribution. In this work, a new ASC extraction method is proposed. It is based on 2-D Prony method and motivated by SPLIT. Position estimation performance of SPLITs local peak detection is compared to the 2-D Prony …

Experimental Assessment Of Photovoltaic Irrigation System, Khalil Raza

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Agriculture is a significant measure of an economy for a number of countries in the world. Currently, the agriculture sector relies heavily on conventional sources of energy for irrigation and other purposes. When, considering factors such as increasing costs of fossil fuels and extending new power lines, especially to remote locations where grid electricity is either inaccessible or expensive, a solar PV (photovoltaic) irrigation system can be an effective choice for irrigating farmland. Solar power eliminates the need to run electrical power lines to remote agriculture locations, which quickly turns the monetary equation in favor of solar irrigation over grid-powered …

Dynamic Cache Partitioning For Multi-Core Systems, Yang Zhang

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As the power consumption (power wall) is limiting the clock frequency increase, multi-core and many-core processors become the major-trend of the new generation of processors. One of the biggest challenges to achieve high performance in multi-core systems is the growing disparity between processor and memory speeds. The "memory wall"' problem, i.e., the growing disparity of speed between the processor and the memory, becomes even more serious in the multi-core systems. Caches have been highly successful in bridging the processor-memory performance gap by providing fast access to frequently used data. Caches also save power by limiting expensive off-chip memory accesses. In …

Hysteretic Controlled Dc-Dc Converters, Shweta Chauhan

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Switched-mode DC-DC converters are widely used in applications requiring step-up and step-down of DC voltages or currents. These converters find their use in portable applications such as laptops and smart phones, radio-frequency power amplifiers, as light emitting diode (LED) drivers, etc. The power converters consist of a switching network, energy storage elements such as inductors and capacitors, and a load resistor. Transformers are used in converters, which require isolation. The switching network comprises of MOSFETs and diodes. With improvement in the VLSI technology, smaller MOSFETs with increased power handling capability are pushing the speed of operation of these power converters …

6 Ghz Rf Cmos Active Inductor Band Pass Filter Design And Process Variation Detection, Shuo Li

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A 90nm CMOS active inductor band pass filter with automatic peak detection is demonstrated in this thesis. The active inductor band pass filter has a better performance than the passive band pass filter in on-chip circuit design, due to small area, larger gain and tunable frequency. However, process variation makes the active inductor band pass filter hard to be used widely in many applications. To settle this issue, an automatic voltage peak detector is introduced to detect the process variation direction and hope to be used to control the active inductor band pass filter center frequency and gain. The designed …

Non-Contact, Antenna-Free Probes For Characterization Of Thz Integrated-Devices And Components, Prasanna Kumar Daram

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The most common technology for electrical characterization of THz devices is DC-coupled contact probes. In this Masters thesis, a non-contact, antenna-free probe is analyzed for characterizing THz devices and integrated circuits. The probe consists of on-chip receiving or transmitting THz photomixers in a co-planar waveguide environment. Our probes are coupled to a CPW-embedded DUT by polarization current rather than conduction current and then down converted in frequency to baseband by an optically pumped photomixer. We investigated probe performance through numerical simulations using High Frequency Structure Simulator (HFSS) carried up to 1 THz and yielded a broadband design with DUT to …

A Theoretical Adaptive Autonomy Model: Real-Time Physiological Assessment Of Cognitive Workload, Dakota C. Evans

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Increases in modern-day system complexity, has led for a need to improve human performance and the interaction between the two. Three objectives: (1) to investigate physiological measures as indicators of cognitive workload, (2) to assess cognitive workload during human interaction with different autonomy levels, and (3) to develop a theoretical model for an adaptive autonomous system that changes with real-time cognitive workload measures were addressed. This effort seeks to improve human computer interaction by providing the human with the acceptable level of computer automation based on real-time cognitive state. Two experiments involved collection of measures of subject physiology, subjective survey …