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Design Of Metal Oxides/Metal Sulfides For The Improvement Of Sodium Ion Batteries, David E. Flores
Design Of Metal Oxides/Metal Sulfides For The Improvement Of Sodium Ion Batteries, David E. Flores
Theses and Dissertations
Herein, the improvement in performance for sodium ion batteries (NIBs) is discussed from available literature and work conducted in the laboratory setting to demonstrate the ability of sodium to perform in the world of energy storage. The reason that sodium is being explored as an alternative to Lithium in energy storage devices is because of the potential depletion of the lithium in the world causing lithium prices to surge. Researchers show that many Sn, Sb, Ge, and other composites perform well as anode materials within NIBs. The research conducted in the dissertation applies the Forcespinning method to produce fibers for …
Study Of Latent Heat Thermal Energy Storage Systems For Concentrated Solar Power Plants, Hermes Chirino
Study Of Latent Heat Thermal Energy Storage Systems For Concentrated Solar Power Plants, Hermes Chirino
Theses and Dissertations
Concentrated Solar Power (CSP) using phase change material (PCM) as the storage medium in the Thermal Energy Storage (TES) system is a promising technology for large scale utilization of solar thermal energy because heat latent heat thermal energy storage (LHTES) systems can store more energy as the latent heat during the melting process.
This study analyzes the different dimensionless parameters from the 1-D transient enthalpy-based mathematical model used to simulate the heat transfer and flow within the LHTES system. These dimensionless parameters are varied and analyzed with the main objective of increasing thermal energy storage efficiency and exergy efficiency of …
Growth And Characterization Of Gallium Oxide Thin Films And Devices, Jorge Castillo
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
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.
Single Tower Crane Allocation Models Using Ant Colony Optimization, Carlos Abelardo Trevino
Single Tower Crane Allocation Models Using Ant Colony Optimization, Carlos Abelardo Trevino
Theses and Dissertations
The construction industry greatly benefits from the utilization of heavy machines and equipment to accomplish successful projects. Tower cranes, in specific, have a crucial role in the transportation of material loads across the site. Because these machines are fixed to the ground, it is essential for planners and managers to position them in a location that provides the most efficient transfer of materials possible. This is commonly known as the tower crane allocation problem, and many researchers have attempted to optimize the tower crane location using mathematical, artificial intelligence, and simulation approaches. However, many works from the literature contain critical …
Des And Tdes Performance Evaluation For Non-Pipelined And Pipelined Implementations In Vhdl Using The Cyclone Ii Fpga Technology, Edni Del Rosal
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 …
Effect Of Processing Parameters On The Electrochemical Performance Of Forcespun Metal Oxide/Carbon Composite Fibers For Li-Ion Batteries, Howard A. Campos
Effect Of Processing Parameters On The Electrochemical Performance Of Forcespun Metal Oxide/Carbon Composite Fibers For Li-Ion Batteries, Howard A. Campos
Theses and Dissertations
Metal oxides have been gaining interest as electrode materials for rechargeable Li-ion batteries due to various properties including low cost, low toxicity, and high theoretical capacity. In this research work the effect of two different metal oxide/carbon fiber composites, Fe3O4/C and ZnO/C, on the electrochemical performance for Li-ion batteries will be explored. This is also the first time that results are reported, to the best of our knowledge, of these fiber composites through the Forcespinning ® method. Scanning electron microscopy (SEM), Energy-Dispersive X-ray Analysis (EDS), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), and electrochemical analysis were used to investigate …
Characterization Of Lift And Drag On Two Dimensional Airfoils With And Without Sinusoidal Leading Edges, Gregorio I. Acosta
Characterization Of Lift And Drag On Two Dimensional Airfoils With And Without Sinusoidal Leading Edges, Gregorio I. Acosta
Theses and Dissertations
An experimental investigation was taken on a 63-021 NACA airfoil, to characterize lift and drag and how the effects of sinusoidal leading edges affect the aerodynamic properties. A theoretical model is also purposed by implementing a perturbation on thin-airfoil theory.
Two sets of airfoils were machined and tested inside a low-speed open circuit wind tunnel. Data from a pressure scanner and particle image velocity will give an insight of how the modified leading edges affect the aerodynamic properties. A Fourier series expansion was used to solve for the lifting-line model, by use of thin-airfoil theory and complex number theory.
Strategic Sensemaking And Software Asset Management: Linkages Between Interpretation And Organizational Action, Juan A. Chavarria
Strategic Sensemaking And Software Asset Management: Linkages Between Interpretation And Organizational Action, Juan A. Chavarria
Theses and Dissertations
Software is a critical information technology (IT) asset as it plays a key role in the creation of organizational value and it ranks as the first or second most important IT budget disbursement. Organizations are expected to govern software to ensure its efficient use while protecting the copyright of software developers.
Software asset management (SAM) focuses on the good governance and effective lifecycle management of software. SAM impacts the flexibility to support business strategies with software, and protects organizations against liability and security risks associated with software use. Since the 1990s, practitioners and scholars posit that SAM is a strategic …
Algan/Gan Hemt By Magnetron Sputtering System, Roman Garcia Perez
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 …
Development Of Lower Rio Grande River Water Quality Transportation Numerical Model For Bi-National River Management, Jose O. Gonzalez
Development Of Lower Rio Grande River Water Quality Transportation Numerical Model For Bi-National River Management, Jose O. Gonzalez
Theses and Dissertations
Traditionally, water quality modelling has focused on modelling individual water bodies. However, water quality management problems must be analyzed at the larger scale to include influences from various water bodies that are interconnected. This paper provides a study on the hydrologic and quality transportation calculation by developing a hydrodynamic (unsteady state) channel routing model using a water-balanced approach. A one dimension Lagrangian river model was developed and applied to the 210 plus miles for the lower Rio Grande River Basin from the Falcon Dam to the head water of Brownsville that pours onto the Gulf of Mexico. This model can …
Multi-Functional System For Biomedical Application Using Ac Electrokinetics, Rakesh Guduru
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 …
Using Pedagogical Tools To Help Hispanics Be Successful In Computer Science, Rodger Irish
Using Pedagogical Tools To Help Hispanics Be Successful In Computer Science, Rodger Irish
Theses and Dissertations
Irish, Rodger, Using Pedagogical Tools to Help Hispanics Be Successful in Computer Science. Master of Science (MS), July 2017, 68 pp., 4 tables, 2 figures, references 48 titles. Computer science (CS) jobs are a growing field and pay a living wage, but the Hispanics are underrepresented in this field. This project seeks to give an overview of several contributing factors to this problem. It will then explore some possible solutions to this problem and how a combination of some tools (teaching methods) can create the best possible outcome. It is my belief that this approach can produce successful Hispanics to …
Thermal Consolidation Of Dredge Sand For Artificial Reef Formations, Alexandro Trevino
Thermal Consolidation Of Dredge Sand For Artificial Reef Formations, Alexandro Trevino
Theses and Dissertations
Coral Reef ecosystems have degraded over years due to a variety of environmental issues such as ocean acidification. The continuous stress has detrimental effects on coral reef ecosystems that can possibly lead to the loss of the ecosystem. Our research aims to construct a prototype of an artificial reef by consolidating dredge sand from the ship channels of South Texas. Consolidation is achieved through an aluminum polytetrafluoroethylene self-propagating high temperature process that yields a solid formation to mimic the physical properties of coral reef structures. Using thermodynamic calculations, the variation of initial components was determined that reached an adiabatic temperature …
A Simple Multi-Core Functional Cache Design Simulator, Rano Mal
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 …
Formation Of Lifepo4-Pan Submicron Fibers Via Forcespinning ® For Battery Cathode Applications, Ashlee L. Lopez
Formation Of Lifepo4-Pan Submicron Fibers Via Forcespinning ® For Battery Cathode Applications, Ashlee L. Lopez
Theses and Dissertations
LiFePO4/C composite nanofibers were prepared by utilizing Forcespinning® technology and calcination approaches. Polyacrylonitrile (PAN) was dissolved in N, N-dimethylformamide (DMF) to produce the media that allotted nanofiber formation via Forcespinning® and also served as the carbon source. A LiFePO4 solution was synthesized separately in DMF, which served as the precursor. The separately prepared PAN/DMF and LiFePO4/DMF solutions were then mixed at different weight percent’s (wt.%) prior to being subjected to Forcespinning ®. Elemental analysis of the LiFePO4/PAN nanofibers was characterized by energy dispersive spectroscopy (EDS) and x-ray photoelectron spectroscopy (XPS). The study of the surface morphology was conducted by scanning …
A Study On The Effects Of Mutation On Populations Using Strategies While Playing Iterative Prisoner's Dilemma, Ramses Romulus De Guzman Reyes
A Study On The Effects Of Mutation On Populations Using Strategies While Playing Iterative Prisoner's Dilemma, Ramses Romulus De Guzman Reyes
Theses and Dissertations
This thesis examines the effects different types of mutation and mutation rates have on populations using strategies while playing the Iterative Prisoners Dilemma (IPD). The system used in order to conduct this study was used in Leas et al. (2016), which uses genetic algorithms as a means of studying memory and its impact on populations playing IPD. For this study, experiments are organized into three different environments: Control, Static and Dynamic. The Control Environment focuses on analyzing the system and forming initial results. The Static Environment focuses on studying the effects of different rates on strategic populations playing IPD, while …
Discrete Element Analysis Of Scb Variability: Asphalt Mixtures, David Saul Renteria
Discrete Element Analysis Of Scb Variability: Asphalt Mixtures, David Saul Renteria
Theses and Dissertations
The Semi-Circular Bending (SCB) test was modeled using the Discrete Element Method (DEM) implemented in numerical software Particle Flow Code (PFC). The fracture analysis of the SCB was studied using two mixtures gradation, Superpave and Coarse Matrix High Binder. The aggregate phase in the model was achieved by using two-dimensional aggregate images with different angularity indexes. The study of the variability of the SCB extends to the random generation of aggregate particles and air voids in the model, in addition to changing the properties at the interface between the aggregate and mastic phases. Results indicate the strong influence of the …
Randomized Approach Tor Set Cover With Multiple Phases*, Ujjwol Subedi
Randomized Approach Tor Set Cover With Multiple Phases*, Ujjwol Subedi
Theses and Dissertations
We Develop an interactive algorithm for the set cover problem. The algorithm uses multiple stages and select some sets each stage via random samples among the uncovered points. We show that it has a O(log n)—approximation ratio and takes O(log n) rounds and O(m2+ϵ ) samples each round, where n is the size of universal set and m is the number of sets.
We also prove a Ω(√logn/loglogn) lower bound for both the number of phases if each phase has poly(m) the number of samples.
Time Dependent Solution For An Incompressible Viscous Fluid Flow In A Cavity, Bishnu Parajuli
Time Dependent Solution For An Incompressible Viscous Fluid Flow In A Cavity, Bishnu Parajuli
Theses and Dissertations
The Finite Element Method is used to find the time dependent solution for an incompressible viscous fluid flow in a cavity in two dimension. The governing equations for this system are the continuity equation and the momentum equation. We use finite element method to obtain the dependent variables. Here we derive weak formulation and develop finite element model by using Galerkin Method. Then we compute velocity components of the fluid for a square cavity. The numerical results are presented.
Design And Implementation Of A Pid Controller For The Low-Speed Wind Tunnel, Carlos F. Vasquez
Design And Implementation Of A Pid Controller For The Low-Speed Wind Tunnel, Carlos F. Vasquez
Theses and Dissertations
The purpose of this research is to investigate the implementation of an external PID controller on an existing variable frequency motor drive (VFD) while using MODBUS communication to read/write data from a LabVIEW station. LabVIEW is the chosen user interface and programming language. It allows human-machine interfacing for the collecting, displaying of information, and automation of the system. The main objective was to develop a new controller to facilitate the operation of the wind tunnel. The current setup makes the operator set the motor frequency manually which then correlates to a test section wind velocity. This involved a calibration period …
Casimir And Van Der Waals Effects On Electrostatically Actuated Nems Resonator Sensors, Christian Reyes
Casimir And Van Der Waals Effects On Electrostatically Actuated Nems Resonator Sensors, Christian Reyes
Theses and Dissertations
The behavior of nano and micro-electromechanical systems (N/MEMS) cantilever beams under electrostatic actuation is studied. The cantilever system is actuated by soft AC voltage that is set to a frequency of near half natural and near natural frequency of the beam. These actuating frequencies result in primary and parametric resonances, respectively. Two methods are used to analytically model the behavior of the cantilever. The first method is Method of Multiple Scales (MMS), which is a perturbation method that works for small parameters. The second method is the Reduced Order Method (ROM), which is a Galerkin method that works for large …
Fractals, Randomization, Optimal Constructions, And Replication In Algorithmic Self-Assembly, Cameron Chalk
Fractals, Randomization, Optimal Constructions, And Replication In Algorithmic Self-Assembly, Cameron Chalk
Theses and Dissertations
The problem of the strict self-assembly of infinite fractals within tile self-assembly is considered. In particular, tile assembly algorithms are provided for the assembly of the discrete Sierpinski triangle and the discrete Sierpinski carpet.
The robust random number generation problem in the abstract tile assembly model is introduced. First, it is shown this is possible for a robust fair coin flip within the aTAM, and that such systems guarantee a worst case O(1) space usage. This primary construction is accompanied with variants that show trade-offs in space complexity, initial seed size, temperature, tile complexity, bias, and extensibility.
This work …
A High Density Micro-Electrocorticography Device For A Rodent Model, Mukhesh Kumar Koripalli
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 …