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 …

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 …

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.

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.

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 …

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 …

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 …

Low Temperature Flexible Perovskite Solar Cell With Mesoporous Tio2 Electron Transport Layer In High Humidity Environment, Felipe De La Torre

Theses and Dissertations

Perovskite solar cells are the fastest advancing solar technology to date with efficiencies increasing from 3.9% to more than 21% within a few years. They have emerged as a possible alternative to silicon photovoltaics due to their exceptional photovoltaic performance, light absorbing properties, and low-cost fabrication with methylammonium lead iodide (CH3NH 3PbI3) getting considerable interest in research and development. However, there are still many challenges that must be addressed for perovskite solar cells to replace contemporary solar cells, such as improving their stability, making them nonhazardous, further increasing their efficiency, and developing better techniques for large scale fabrication. In this …

Router Security Effect On Performance Of A Network, David L. Leal

Theses and Dissertations

Recently many of the devices that create a computer network offer security to help protect networks from hackers, such as computers, servers, firewalls and even routers. In most cases when protecting a network from hackers having more security is not always the best, because the more resources of the device is used by the security in inspecting connections, and it can compromise performance of the network.

This thesis investigates performance benefit of having security on a router and its impact on the connection rate of the network when it is under security attacks. In this thesis, different security features and …

Biocompatible Microchannel Scaffold With Microwires For Recording Regenerative Peripheral Nerve Neural Spikes, Manisankar Chennamsetti

Theses and Dissertations

A new process for the fabrication of a microchannel scaffold with microwires for peripheral nerve applications is presented. This microchannel scaffold implemented between the ends of nerves, the axons of which regenerate through microchannel in scaffold and fixed microelectrodes. This device is entirely handcrafted using commercially available materials such as microwires, PDMS film, liquid PDMS, dental cement, and epoxy glue. This device was implemented in the a Lewis rat sciatic nerve to better analyze the electrical signals of regenerated axons. 64-electrode microchannel scaffolds were developed for both peripheral nerve interfacing and peripheral nerve regeneration. The microwires were used for recording …

Microwire Regenerative Peripheral Nerve Interfaces With Wireless Recording And Stimulation Capabilities, Ali Ajam

Theses and Dissertations

A scalable microwire peripheral nerve interface was developed, which interacted with regenerated peripheral nerves in microchannel scaffolds. Neural interface technologies are envisioned to facilitate direct connections between the nervous system and external technologies such as limb prosthetics or data acquisition systems for further processing. Presented here is an animal study using a handcrafted microwire regenerative peripheral nerve interface, a novel neural interface device for communicating with peripheral nerves. The neural interface studies using animal models are crucial in the evaluation of efficacy and safety of implantable medical devices before their use in clinical studies.16-electrode microwire microchannel scaffolds were developed for …

Impact Of Virtualization On Cloud Network Security, Koushicaa Sundar

Theses and Dissertations

In this thesis, experimental evaluation of the effect of virtualization on the availability of servers has been performed under Distributed Denial of Service (DDoS) attacks for popular server Operating Systems such as Windows Server 2008 R2, Windows Server 2012 R2 virtualized using Hyper-V. A comparative evaluation of the performance of the servers before and after virtualization under DDoS attacks indicates that after virtualization there is a considerable increase in the vulnerability to attacks and a decline in the performance of the virtualized server compared to when the server is not virtualized.

Handcrafted Electrocorticography Electrodes For A Rodent Neural Activity, Nishat Tasnim

Theses and Dissertations

Electrocorticography (ECoG) is a minimally invasive neural recording method that has been extensively used for neuroscience applications. Although many neural recording methods exist, ECoG provides a combination of stability, high spatial and temporal resolution with chronic and mobile capabilities. This paper presents an animal study using a low cost and simple handcrafted ECoG electrode that is made of commercially accessible materials. The study is performed on a Lewis rat implanted with a handcrafted 32-channel non-penetrative ECoG electrode covering an area of 3 x 3 mm 2 on the cortical surface. The ECoG electrodes were placed on the motor and somatosensory …

A Handcrafted Multi-Branch Nerve Scaffold For In Vivo Peripheral Nerve Regeneration, Ridwan Fayaz Hossain

Theses and Dissertations

Arm and leg peripheral nerve injuries contribute largely to functional disability. These injuries seldom affect a single-line nerve; rather the injury goes beyond and disrupts the nerve tissue across multiple nerve paths. Here we investigate handcrafted PDMS based multi-branch nerve guidance conduit, which addresses this crucial branching from the sciatic nerve to aid with the regeneration to their appropriate distal targets. The design concept of the developed multiple branch nerve scaffolds is not specific for the sciatic nerve but can be modified for general use of all peripheral nerves and additional applications. Microchannels are also fabricated into a device in …

Pdms Microchannel Scaffolds For The Isolation Of Individual Axon Regeneration, Bong Kyun Kim

Theses and Dissertations - UTB/UTPA

Injuries to the peripheral nervous system often result in the loss of sensory or motor function within the effected nerve. Nerve scaffolds provide the mechanical support and topographical cues to axon regeneration such that the gap within the injured nerve is bridged and functional recovery is restored. The Microchannel Peripheral Nerve Scaffold, µPNS, was fabricated from PDMS using micromachining techniques that allow for the unprecedented control of microchannel dimensions and paths and therefore, the production of highly customizable Nerve scaffolds for peripheral nerve regeneration applications. The device was then implanted within the sciatic nerves of a series of Lewis rats, …

Security Integrity Of Ekg Signal Monitoring Under Different Network Attack Conditions, Raghava Teja Pingali

Theses and Dissertations - UTB/UTPA

This thesis focuses on issues related with monitoring of EKG signals under different network attack traffic conditions. It is becoming common for modern hospitals to monitor real time EKG signals of patients on computers that are usually connected to networks. If the network suffers with attack conditions, it can affect connected computers and alter EKG signals monitoring, hence raising false alarms. Denial of Service attacks may silently affect the real time monitoring of EKG signals. Altering of EKG signals may result in loss of integrity and it can violate CIA triad of security. In this thesis, different attack conditions were …

Improving Queueing Implementation On High Speed Switches, Wendy Hernandez

Theses and Dissertations - UTB/UTPA

In this thesis two different conventional shared memory allocation schemes - Dynamic Threshold (DT) and Threshold-based Filtering (TF) - are evaluated under varied traffic conditions in order to determine the optimal configuration for each tested scenario. The effect that a changing ABL, load, and ratio between buffer size and ports have on the packet loss is observed for buffer sharing schemes DT and TF schemes. This allowed to easily determining the Alpha and Thresholds required by DT and TF schemes respectively to obtain an optimal configuration under each of the different tested scenarios. A new shared memory allocation scheme referred …

Distributed Coordinate Tracking Control Of Multiple Wheeled Mobile Robots, Yifan Xing

Theses and Dissertations - UTB/UTPA

In this thesis, distributed coordinate tracking control of multiple wheeled-mobile robots is studied. Control algorithms are proposed for both kinematic and dynamic models. All vehicle agents share the same mechanical structure. The communication topology is leader-follower topology and the reference signal is generated by the virtual leader. We will introduce two common kinematic models of WMR and control algorithms are proposed for both kinematic models with the aid of graph theory. Since it is more realistic that the control inputs are torques so dynamic extension is studied following by the kinematics. Torque controllers are designed with the aid of backstepping …

Electrocardiogram Data Collection Under Network Attacks On The Mac Platform, Golshan Famitafreshi

Theses and Dissertations - UTB/UTPA

Increasing heart disease among human beings needs more precise treatment, which requires monitoring of electrocardiogram (ECG). In many cases, real time monitoring of ECG is needed via wireless or wireline networks. Use of network-connected computers for monitoring proposes can raise security issues, which can be created by viruses, worms, or external agents such as DoS attack traffic. Any alteration of this biomedical signal can lead to wrong diagnosis and wrong treatment. Furthermore, in healthcare industry, HIPAA rules require health information to be kept secure by providing confidentiality, integrity, and availability. This thesis investigates how integrity and availability of remotely monitored …

Evaluation Of Security Vulnerabilities Of Popular Computer And Server Operating Systems Under Cyber Attacks, Rodolfo Baez Jr.

Theses and Dissertations - UTB/UTPA

Nowadays many operating systems are including security features in order to prevent network attacks, and since one of the roles of the OS is to manage the resources as efficient as possible. It is imperative to investigate the protection that is provided. Therefore, the scientific significance of this thesis was to evaluate, what type of built-in defense mechanisms that different OS’s had in place in order to mitigate these network attacks. In this thesis, we considered the security of the following globally deployed computer OS’s: Microsoft’s Windows 7, Apple’s OS X Lion, and Ubuntu 13.10. Furthermore, we also tested four …

Characterization Of Gan Thin Films Grown By Rf Magnetron Sputtering For Fabrication Of An Algan/Gan Hemt Biosensor, Rocio Yolanda Garza

Theses and Dissertations - UTB/UTPA

Radio-Frequency (RF) Magnetron Sputtering has been used to grow GaN thin films for future fabrication of an AlGaN/GaN HEMT biosensor. A GaN target was sputtered at various parameters on silicon and sapphire substrates, at room temperature and at elevated temperature using substrate heating and post deposition annealing treatment. The research conducted investigates the effects of sputtering gas (Argon or Nitrogen gas), RF power (40W or 50W), and pressure (4mT – 30mT) on the structural properties of the thin films. Imaging tools such as the Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDS), X-ray Diffractometer (XRD), and …

Seeds Of Solutions™: An Economical & Efficient Approach Towards Power Engineering Education, Eli Alvarez

Theses and Dissertations - UTB/UTPA

Power demands are set to increase over the next twenty years; however, research shows that there may be a shortage of power engineers due to an appreciable percentage of the current power engineer workforce retiring, insufficient enrollment in power engineering programs and a lack of emphasis in power engineering at the university level. This thesis provides supporting research for future power demands, workforce and faculty shortages. Using temporary research in modern learning / teaching styles, student / teacher perceptions, educational trends and regional course offerings, this thesis describes a learning approach towards power engineering education. Designed specifically for universities with …

A 129nw Neural Amplifier And Gm-C Filter For Eeg Using Gm/Id Methodology, Samuel A. Gallegos

Theses and Dissertations - UTB/UTPA

This Thesis presents a low-power analog front-end amplifier and Gm-C filter for biomedical sensing applications, specifically for Electroencephalogram (EEG) use. The proposed neural amplifier uses a supply voltage of 1.8V, it has a mid-band gain of 40.75dB, and consumes a total current of 71.82nA, for a total dissipated power of 129.276nW. Also presented is the design of a 3rd order Butterworth Low Pass Gm-C Filter which makes use of 14.7nS transconductors; the proposed filter has a pass band suitable for EEG recording use (1-100Hz). The amplifier and filter utilize current sources without bias resistances which provide 56nA and (1.154nA x …

Applications Of Magnetostrictive Materials In The Real-Time Monitoring Of Vehicle Suspension Components, Raul Estrada

Theses and Dissertations - UTB/UTPA

The purpose of this project is to explore applications of magnetostrictive materials for real-time monitoring of railroad suspension components, in particular bearings. Monitoring of such components typically requires the tracking of temperature vibration and load. In addition, real-time, long-term monitoring can be greatly facilitated through the use of wireless, self-powered sensors. Magnetostrictive materials, such as Terfenol-D, have the potential to address both requirements. Currently, piezoelectrics are used for many load and energy harvesting applications; however, they are fragile and are difficult to use for static load measurements. Magnetostrictive metals are tougher, and their property of variable permeability when stressed can …

Cluster Computer Simulation Of Buffer Sharing Schemes Under Bursty Traffic Load, Javier Castillo

Theses and Dissertations - UTB/UTPA

In this thesis it is first analyzed the effect that different Average Burst Length, buffer size or number of ports have on the performance in terms of packet loss ratio on shared memory network switches using Complete Sharing as baseline for the memory allocation scheme. Three different shared memory allocation schemes - Sharing with a Minimum Allocation (SMA), Sharing with Maximum Queue lengths (SMXQ), and Dynamic Threshold (DT) - are then analyzed under varied traffic conditions in order to determine the best configuration for each tested scenario. Having determined the best configuration for each individual scheme under all the tested …

Distributed Formation Tracking Control Of Multiple Car-Like Robots, Chunyu Chen

Theses and Dissertations - UTB/UTPA

In this thesis, distributed formation tracking control of multiple car-like robots is studied. Each vehicle can communicate and send or receive states information to or from a portion of other vehicles. The communication topology is characterized by a graph. Each vehicle is considered as a vertex in the graph and each communication link is considered as an edge in the graph. The unicycles are modeled firstly by both kinematic systems. Distributed controllers for vehicle kinematics are designed with the aid of graph theory. Two control algorithms are designed based on the chained-form system and its transformation respectively. Both algorithms achieve …