Engineering Commons^™

Security Assessment Of Select Computer Systems Under Distributed Denial Of Service Attacks Performed By Botnets, Hugo Armando Herrera Martinez

Theses and Dissertations

With the passage of time Internet connectivity has been found on more electronic devices than in previous decades. This continuous development may be perceived as a double-edged sword. While the world becomes more Internet-connected and quality of life increases, the lack of proper security protocols in some of these electronic devices permits illegitimate parties to take control of them for their own malicious purposes.

This thesis studies the impact of compromised Internet-connected devices on commonly used server operating systems: Microsoft’s Windows Server 2012 R2 Datacenter, Windows Server 2016 Datacenter, and Apple’s macOS 10.13.6 High Sierra deployed on Apple’s Mac Pro …

Boron Nitride Thin-Film Deposited By Rf Magnetron Sputtering, Jesus A. Valladares Gonzalez

Theses and Dissertations

Cubic Boron Nitride is considered a superhard material, its thermochemical stability makes it suitable for applications with corrosive environments and high temperatures. C-BN is grown by PDV on Si substrates. The plasma is energized via an RF source to sputter the target. The ion species in the plasma can be described by the classic electrodynamic expression . Plasma temperature is given by T = (6.2836*E/8*k). The sputter is given by the ratio of the heat transfer to the enthalpy of formation , of the target. The Hall Measurement is performed as recommended by NIST. The measurement was performed on a …

Using Multifactor Inputs Bp Neural Network To Make Power Consumption Prediction, Hao Song

Graduate Dissertations and Theses

With the development of modern information and technology (IT), smart grids became one of the major components of smart cities, to take full advantage of the smart grid, the capability of intelligent scheduling and planning of electricity delivery is essential. For this purpose, researchers have investigated methodologies for power consumption prediction and demand side management (DSM). In addition, conducting a comprehensive analysis and obtaining an accurate evaluation of power consumption are the premise and basis for a more robust and efficient power grid design and transformation. Therefore, it is meaningful to explore forecasting models that are able to reflect the …

Design Of A Multidirectional Wear Testing Device For Simulating Wear Of Biocompatible Materials Used In Joint Implants, Carlos A. Rodriguez Betancourth

Theses and Dissertations

In the present work, a novel multidirectional pin-on-disc wear testing device designated CNC-POD (computer-numerical-control pin-on-disc) capable of replicating the cross-shear motions experienced by a prosthesis in vivo was designed and developed in the UTRGV in order to evaluate the wear resistance of new biomaterials. The CNC-POD consists of six temperature-controlled pin-on-disc stations mounted on a two-axis CNC table (X-Y). Each pin-on-disc station is load-programmable up to 510 Newtons (115 pounds). The CNC table allows the machine to reproduce a wide range of 2D patterns in millimeter scale on the six stations under a specific load. Friction force is measured during …

Buffer Controlled Cache For Low Power Multicore Processors, Marven Calagos

Theses and Dissertations

This thesis proposes a buffered dual access mode cache to reduce power consumption in multicore caches for embedded systems. This cache is called Buffer Controlled Cache (BCC cache). The proposed scheme introduces a pre-cache buffer to determine how to access the cache. The proposed cache shows better prediction rates and lower power consumption than conventional caches, such as Phased cache and Way-prediction cache. For single core implementation, Simplescalar and Cacti simulators have been used for these simulations using SPEC2000 benchmark programs. The experimental results show that the proposed cache improves the power consumption by 37%-42% over the conventional caches. Multi2Sim …

Cyber-Physical Embedded Systems With Transient Supervisory Command And Control: A Framework For Validating Safety Response In Automated Collision Avoidance Systems, Daniel K. Trembley

Graduate Dissertations and Theses

The ability to design and engineer complex and dynamical Cyber-Physical Systems (CPS) requires a systematic view that requires a definition of level of automation intent for the system. Since CPS covers a diverse range of systemized implementations of smart and intelligent technologies networked within a system of systems (SoS), the terms “smart” and “intelligent” is frequently used in describing systems that perform complex operations with a reduced need of a human-agent. The difference between this research and most papers in publication on CPS is that most other research focuses on the performance of the CPS rather than on the correctness …

Image Series Prediction Via Convolutional Recurrent Neural Networks With Limited Training Data, Zao Zhang

Graduate Dissertations and Theses

This thesis focuses on developing deep learning algorithms that can be used to forecast the image series under limited training data. Specifically, we study the problem of using a pine tree's existing appearance images to predict its future appearance images.

Side-Information For Steganography Design And Detection, Tomas Denemark

Graduate Dissertations and Theses

Today, the most secure steganographic schemes for digital images embed secret messages while minimizing a distortion function that describes the local complexity of the content. Distortion functions are heuristically designed to predict the modeling error, or in other words, how difficult it would be to detect a single change to the original image in any given area. This dissertation investigates how both the design and detection of such content-adaptive schemes can be improved with the use of side-information.

We distinguish two types of side-information, public and private: Public side-information is available to the sender and at least in part also …

Growth And Characterization Of Gallium Oxide Thin Films And Devices, Jorge Castillo

Theses and Dissertations

Gallium oxide has promising physical and electrical properties for power applications and optoelectronics. thermally grown oxide developed from sputtered GaN layers and gallium oxide substrates will be characterized. The study will evaluate a variety of temperatures in order to investigate the advantages and disadvantages on each of the synthetization techniques.

Des And Tdes Performance Evaluation For Non-Pipelined And Pipelined Implementations In Vhdl Using The Cyclone Ii Fpga Technology, Edni Del Rosal

Theses and Dissertations

Two ongoing issues that engineers must face in the new era of data analytics are performance and security. Field Programmable Gate Arrays (FPGAs) offer a new solution for optimizing the performance of applications while the Data Encryption Standard (DES) and the Triple Data Encryption Standard (TDES) offer a mean to secure information. In this thesis we present a Non-Pipelined and Pipelined, in Electronic Code Book (EBC) mode, implementations in VHDL of these two commonly utilized cryptography schemes. Using Altera Cyclone II FPGA as our platform, we design and verify the implementations with the EDA tools provided by Altera. We gather …

Security Evaluation Of Virtualized Computing Platforms, Ganesh Reddy Gunnam

Theses and Dissertations

In this thesis, security experiments were conducted to evaluate embedded security protocol performance of two leading server operating systems, Apple’s MAC OS server LION Vs. Microsoft’s Windows server 2012 R2 OS under different types of security attack. Furthermore, experiments were conducted to understand and evaluate the effect of virtualization using Hyper-V with Windows 2012 R2 OS on MAC hardware platform. For these experiments, connection rate, connection latency, non-paged pool allocations and processor core utilization for different OS, virtual machines, and under different traffic types were measured.

Algan/Gan Hemt By Magnetron Sputtering System, Roman Garcia Perez

Theses and Dissertations

In this thesis, the growth of the semiconductor materials AlGaN and GaN is achieved by magnetron sputtering for the fabrication of High Electron Mobility Transistors (HEMTs). The study of the deposited nitrides is conducted by spectroscopy, diffraction, and submicron scale microscope methods. The preparation of the materials is performed using different parameters in terms of power, pressure, temperature, gas, and time. Silicon (Si) and Sapphire (Al2O3) wafers are used as substrates. The chemical composition and surface topography of the samples are analyzed to calculate the materials atomic percentages and to observe the devices surface. The instruments used for the semiconductors …

Multi-Functional System For Biomedical Application Using Ac Electrokinetics, Rakesh Guduru

Theses and Dissertations

Manipulation of fluids in a small volume is often a challenge in the field of Microfluidics. While many research groups have addressed this issue with robust methodologies, manipulating fluids remains a scope of study due to the ever-changing technology (Processing Tools) and increase in the demand for “Lab-On-a-Chip” devices in biological applications. This thesis peruses the flow pattern of the orthogonal electrode pattern and circular electrode providing, examples of the flow patterns and the process micromixing. Characteristics of a multifunctional system were demonstrated using orthogonal electrode and circular electrode patterned device. Conductivity of the fluids were chosen such they reflect …

A Simple Multi-Core Functional Cache Design Simulator, Rano Mal

Theses and Dissertations

This paper presents a flexible multi-core cache memory simulator to design and evaluate memory hierarchies for general-purpose or embedded processors. The proposed simulator needs to work with Pin, which is an open-source dynamic instrumentation tool provided by Intel. The Pin intercepts the execution of instructions and generates a sequence code (traces) to feed into the simulator for any selected benchmark programs, such as SPEC2006, SPLASH2, or PARSEC. We have a plan to release this simulator as an open-source (like Pin) to support research and/or academic community for their simulation works. In addition, we expect more functions can be updated on …

Understanding The Surface Fouling Mechanism Of Ultrananocrystalline Diamond Microelectrodes Using Microfluidics For Neurochemical Detection, An-Yi Chang

Doctoral Dissertations

Electrochemical methods are widely used for chronic neurochemical sensing, but thus far, the organic solution redox reactions fouled the electrodes' surface. It caused the reduction of sensitivity and the electrodes' lifetime.

Here, we present the boron-doped nanocrystalline diamond microelectrodes (BDUNCD) as the next generation electrode material for neurochemical sensor development. To aid in long-term chronic monitoring of neurochemicals, they have a wide window of electrochemical potential, extremely low background current, and excellent chemical inertness. The main research goal is to reduce the rate of electrode fouling due to the reaction by-products, and significantly extend their useful lifetime.

We systematically characterize …

Electrochemical Behavior Of Dense Electrodes For Impedancemetric Nox Sensors, Nabamita Pal

Doctoral Dissertations

NOx (NO and NO2) exhaust gas sensors for diesel powered vehicles have traditionally consisted of porous platinum (Pt) electrodes along with a dense ZrO2 based electrolyte. Advancement in diesel engine technology results in lower NOx emissions. Although Pt is chemically and mechanically tolerant to the extreme exhaust gas environment, it is also a strong catalyst for oxygen reduction, which can interfere with the detection of NOx at concentrations below 100 ppm. Countering this behavior can add to the complexity and cost of the conventional NO x sensor design. Recent studies have shown that dense electrodes are less prone to heterogeneous …

Stretching The Limits Of Dynamic Range, Shielding Effectiveness, And Multiband Frequency Response, Matthew J. Hartmann

Doctoral Dissertations

In this dissertation, an RF MEMS variable capacitor suitable for applications requiring ultrawide capacitive tuning ranges is reported. The device uses an electrostatically tunable liquid dielectric interface to continuously vary the capacitance without the use of any moving parts. As compared to existing MEMS varactors in literature, this device has an extremely simple design that can be implemented using simple fabrication methods that do not necessitate the use of clean room equipment. In addition, this varactor is particularly suited for incorporating a wide range of liquid dielectric materials for specific tuning ratio requirements.

Additionally, the shielding effectiveness performance of graphene-doped …

A High Density Micro-Electrocorticography Device For A Rodent Model, Mukhesh Kumar Koripalli

Theses and Dissertations

Electrocorticography (ECoG) is a methodology for stable mapping of the brain surface using local field potentials (LFPs) with a wide cortical region, high signal fidelity, and minimal invasiveness to brain tissue. To compare surface ECoG signals with inter-cortical neuronal activity, we fabricated a flexible handcrafted ECoG electrode made with economically available materials. This research is on a Lewis rat implanted with a handcrafted 256-channel, non-penetrative ECoG electrode covering an area of 7mm x 7mm on the cortical surface. This device was placed on the motor and somatosensory cortex of the brain to record signals with an active animal. The recordings …

Silicon Germanium Bicmos Comparator Designed For Use In An Extreme Environment Analog To Digital Converter, Benjamin Riley Sissons

Graduate Theses and Dissertations

This thesis demonstrates the process of creating a radiation hardened and extreme temperature operating comparator from start to finish in the 90 nm SiGe 9HP process node. This includes the entire design flow from examining comparator topologies, to designing the initial comparator circuits, to simulating the comparator over a temperature range of -196°C to 125°C, and finally the testing of the fabricated circuit. To verify the circuit would work at low temperatures, several new device models were created that could be used for simulations at -196°C. In addition to its properties as a standalone comparator, the circuit was also used …

Characterization Of Coupled Gold Nanoparticles In A Sparsely Populated Square Lattice, Roy Truett French Iii

Graduate Theses and Dissertations

Metal nanoparticles deposited in regular arrays spaced at optical wavelengths support a resonance due to a coherent coupling between localized surface plasmon mode and lattice diffraction allowing for engineering of tunable devices for use in biological sensors, nanoantennae, and enhanced spectroscopy. Techniques such as electron beam lithography, focused ion beam lithography, nanosphere lithography, and nanoimprint lithography are used for fabrication but are limited by cost, device throughput, and small deposition. Polymer soft lithography and continuous dewetting of particles is a potentially viable alternative showing promise in all of those areas. This thesis developed the fabrication of a refined hydrophilic nanoimprinted …

Modeling And Validation Of 4h-Sic Low Voltage Mosfets For Integrated Circuit Design, Shamim Ahmed

Graduate Theses and Dissertations

Silicon Carbide is a promising wide bandgap material and gradually becoming the first choice of semiconductor for high density and high efficiency power electronics in medium voltage range (500-1500V). SiC has also excellent thermal conductivity and the devices fabricated with the material can operate at high temperature (~ 400 ⁰C). Thus, a power electronic system built with SiC devices requires less cooling requirement and saves board space and cost. The high temperature applications of SiC material can also be extended to space exploration, oil and gas rigging, aerospace and geothermal energy systems for data acquisition, sensing and instrumentation and power …

Development Of An Oxygen Saturation Monitoring System By Embedded Electronics, Manikandan Venkatesan Gomathy

Graduate Theses and Dissertations

Measuring Oxygenation of blood (SaO2) plays a vital role in patient’s health monitoring. This is often measured by pulse oximeter, which is standard measure during anesthesia, asthma, operative and post-operative recoveries. Despite all, monitoring Oxygen level is necessary for infants with respiratory problems, old people, and pregnant women and in other critical situations.

This paper discusses the process of calculating the level of oxygen in blood and heart-rate detection using a non-invasive photo plethysmography also called as pulsoximeter using the MSP430FG437 microcontroller (MCU). The probe uses infrared lights to measure and should be in physical contact with any peripheral points …

Investigation Of Fes2 Nanoparticles For Use In Optoelectronic And Thermoelectric Applications, Rick Tefal Eyi Nkoghe

Graduate Theses and Dissertations

Iron pyrite (FeS2) is the most abundant sulfide material on earth. This material has been widely investigated by researchers because of its optical properties. However, it has been difficult to produce High efficiency FeS2 based solar cells. This is due to many different impurities that arise when making the materials. The ability to synthesize pure pyrite FeS2 material is therefore critical for applications.

Pure Iron pyrite nanocrystals were synthesized using hot injection by mixing sulfur with an iron precursor in the presence of an amine. To improve the stability, shorter ligands replaced the native amines ligands. The stability of the …

Linear Quadratic Optimal Control For A Cascaded Converters-Based Microgrid, Amlam Niragire

Graduate Theses and Dissertations

There is a constant transformation of the electric grid due to an ongoing interest in the deployment of renewable energy resources and electric microgrid formation. This transformation, though advantageous in many ways, poses great challenges for the energy industry and there must be a constant improvement in modeling, simulation, analysis and control techniques in order to characterize and optimize the system design and operation. In this light, the scope of this thesis is focused on developing a linear model, analyzing the stability and designing an optimal linear quadratic regulator (LQR) for a microgrid system. The microgrid system used is inspired …

Applications Of Krylov Subspace And Balanced Truncation Model Order Reduction In Power Systems, Sebastian Emanuel Garrido

Graduate Theses and Dissertations

Dynamic representations of power systems usually result in the order of hundreds or even thousands of buses. Therefore, reduction of these dynamic representations is convenient. Two applications of model order reduction in power systems are discussed in this thesis. First, Krylov subspace-based method is applied to the IEEE-123 Node Test Feeder in the context of distribution-level power systems simulation. Second, a Balanced Truncation-based model reduction is implemented in the 3-Machine 9-Bus system for designing a power system controller in the context of generation- and transmission-level power systems.

First, for the IEEE-123 Node Test Feeder, a two-sided Arnoldi algorithm is proposed …

Short-Circuit Protection For Low-Voltage Dc Distribution Systems Based On Solid-State Circuit Breakers, Sharthak Munasib

Graduate Theses and Dissertations

Proper short-circuit protection in dc distribution systems has provided an austere challenge to researchers as the development of commercially-viable equipment providing fast operation, coordination and reliability still continues. The objective of this thesis is to analyze issues associated with short-circuit protection of low-voltage dc (LVDC) distribution systems and propose a short-circuit protection methodology based on solid-state circuit breakers (SSCBs) that provides fault-current limiting (FCL). Simulation results for a simplified notional 1-kVdc distribution system, performed in MATLAB/SIMULINKTM, would be presented to illustrate that SSCB solutions based on reverse-blocking integrated gate-commutated thyristors (RB-IGCT) are feasible for low-voltage dc distribution systems but requires …

Design, Modeling, Fabrication, And Testing Of A Multistage Micro Gas Compressor With Piezoelectric Unimorph Diaphragm And Passive Microvalves For Microcooling Applications, Shawn Thanhson Le

Doctoral Dissertations

This dissertation investigates the development of a multistage micro gas compressor utilizing multiple pump stages cascaded in series to increase the pressure rise with passive microvalves and piezoelectric unimorph diaphragms. This research was conducted through modeling, simulation, design, and fabrication of the microcompressor and its components. A single-stage and a two-stage microcompressor were developed to demonstrate and compare the performance and effectiveness of using a cascaded multistage design.

Steady fluid flow through static microvalves structure was studied to gain insight on its gas flow dynamics and characteristics. Transient analysis combined with the structure's interaction was investigated with an analytical model …

Detection And Interpretation Of Fluorescence Signals Generated By Excitable Cells And Tissues, Anthony J. Costantino

Graduate Dissertations and Theses

Part 1: High-Sensitivity Amplifiers for Detecting Fluorescence
Monitoring electrical activity and Cai 2+ transients in biological tissues and individual cells increasingly utilizes optical sensors based on voltage-dependent and Cai 2+-dependent fluorescent dyes. However, achieving satisfactory signal-to-noise ratios (SNR) often requires increased illumination intensities and/or dye concentrations, which results in photo-toxicity, photo-bleaching and other adverse effects limiting the utility of optical recordings. The most challenging are the recordings from individual cardiac myocytes and neurons. Here we demonstrate that by optimizing a conventional transimpedance topology one can achieve a 10-20 fold increase of sensitivity with photodiode-based recording systems (dependent on …

Statistical Modeling And Simulation Of Variability And Reliability Of Cmos Technology, Khaled Hassan Md

Open Access Dissertations

The introduction of High-κ Metal Gate transistors led to higher integration density, low leakage current, and faster switching speed. However, this transition in technology roadmap brought about new failure mechanisms such as Positive Bias Temperature Instability and Stress Induced Leakage Current. In addition, the relentless downscaling of devices to keep up with Moore's law has significantly increased the time-zero variability caused by Random Dopant Fluctuation, Mean Gate Length Deviation, and Line Edge Roughness. Because of their possible correlation with time dependent aging effects, the quantification of reliability has become more complex than ever. To that effect, we propose a framework …

Two-Dimensional Electronics And Optoelectronics: From Materials Syntheses To Device Applications, Yexin Deng

Open Access Dissertations

The current research on semiconductor device has pushed the scaling of the devices into sub-10 nanometers (nm) regime. While most of the current devices are made on silicon germanium, and III-V materials, people are looking for new materials for use in novel semiconductor devices: either for use in extremely scaled device in sub-10 or even sub-5 nm devices, or for use in other situations such as flexible electronics or low power and lower cost IoT (Internet of Things) applications.

Two-dimensional (2D) materials have attracted extensive research interests in their physical, chemical and mechanical properties.Since the discovery of graphene, which a …