Engineering Commons^™

Economic Analysis Of Solar Assisted Absorption Chiller For A Commercial Building, Gnananesan Antonyraj

Masters Theses and Doctoral Dissertations

Dwindling fossil fuels coupled with changes in global climate intensified the drive to make use of renewable energy resources that have negligible impact on the environment. In this attempt, the industrial community produced various devices and systems to make use of solar energy for heating and cooling of building space as well as generate electric power. The most common components employed for collection of solar energy are the flat plate and evacuated tube collectors that produce hot water that can be employed for heating the building space. In order to cool the building, the absorption chiller is commonly employed that …

Potential Energy Cost Savings By Use Of Building Roofs As Thermal Storage Of A Multi-Storied Building, Ahmad Adam Shelbaya

Masters Theses and Doctoral Dissertations

The thermal mass of a building has been used for more than two decades to shift the peak cooling load occurring during the day time to evening or night time. This is typically accomplished by use of concrete slabs embedded with pipes carrying hot or chilled water to meet the heating or cooling load, respectively. The water temperature drops across the coils and the frequency and intensity of room air circulation can be varied, along with controlling the gains through the windows, to shift the peak load hours to the nighttime when energy costs are cheaper and electric demands are …

Pvt Study Of Selected Uae Reservoir Fluids, Rashid Sher Mohammad

Theses

Phase behavior modeling in crude oil includes prediction of thermodynamic properties (such as saturation pressure, density, viscosity, thermal conductivity, etc.) for the vapor and liquid phases. The aim of phase behavior modeling is to establish the accuracy and reliability of the developed equation of state model to predict various other fluid phase behavior properties at high pressure and temperature conditions.

In the first part of this work, a new and reliable phase behavior apparatus designed in Brazil was used for the two-stage recombination process and phase behavior measurements. The recombination of the surface sample fluids (first-stage separator gas and stock-tank …

Finding The Maximum Magnitude Response (Gain) Of Second-Order Filters Without Calculus, Kenneth V. Cartwright, Patrick Russell, Edit J. Kaminsky

Electrical Engineering Faculty Publications

The maximum gain (with respect to frequency) of second-order filters such as low-pass, high-pass, band-pass, low-pass notch and high-pass notch filters is derived without using calculus. Our method uses the fact that the square of the magnitude response (gain) for these filters can be written as a positive constant divided by a quadratic function of frequency. Hence, the gain is maximized when the denominator of the gain is minimized, which is easily achieved without calculus, as the denominator is parabolic.

Lagrangian Relaxation For Large-Scale Multi-Agent Planning, Geoffrey J. Gordon, Pradeep Varakantham, William Yeoh, Hoong Chuin Lau, Ajay S. Aravamudhan, Shih-Fen Cheng

Research Collection School Of Computing and Information Systems

Multi-agent planning is a well-studied problem with various applications including disaster rescue, urban transportation and logistics, both for autonomous agents and for decision support to humans. Due to computational constraints, existing research typically focuses on one of two scenarios: unstructured domains with many agents where we are content with heuristic solutions, or domains with small numbers of agents or special structure where we can provide provably near-optimal solutions. By contrast, in this paper, we focus on providing provably near-optimal solutions for domains with large numbers of agents, by exploiting a common domain-general property: if individual agents each have limited influence …

Residential Grid-Tied With Battery Backup Photovoltaic System, Thomas Stobuagh

Electrical Engineering

When power outages occur, many homes are left without power for some time as they are dependent on the power grid. This project aims to design a residential grid tied battery backup photovoltaic system that will provide up to 7.2kW in an area that gets 5.36-5.49 kWh/m2/day [1] to support a home with an average daily usage of 28.4 kWh/day. To effectively use this system the house remains connected to the electric utility at all times, so any power needed above what the solar system can produce is simply drawn from the utility. It includes battery backup or uninterruptible power …

Recrystallization Kinetics Of 3c Silicon Carbide Implanted With 400 Kev Cesium Ions, Daniel Denell Osterberg

Boise State University Theses and Dissertations

Polycrystalline 3C silicon carbide was implanted at room temperature with 400 keV cesium ions to a dose of 10¹⁶ ions·cm^-2. The samples were then annealed at 600 – 1000°C for 0-48 hours in ultra-high purity argon. The implanted zone of each sample was characterized by transmission electron microscopy and secondary ion mass spectroscopy. It is shown that the implantation resulted in a 217 ± 2 nm amorphous region with microstructural damage extending to approximately 250 nm below the surface. Recrystallization of the amorphous region was observed at 725°C, although minimal densification was observed until ≥ 800°C. Densification …

Analysis Of Electromagnetic Stimulation Of Transport In Water For Geoenvironmental Applications, Mahsa Azad

Boise State University Theses and Dissertations

Air sparging is a popular soil and groundwater remediation technique, which enables the removal of volatile organic compounds (VOCs) through diffusing contaminant-free air into saturated zones of soil. However, the VOC removal process is slow due to the soils' low permeability, and might take months to years depending on the type of the soil and contaminant. The goal of this thesis is to study the effect of electromagnetic (EM) waves —with minimal heat generation— on transport mechanisms such as diffusion, in order to improve airflow and expedite the cleanup process using air sparging or similar technologies. Because water dipole molecules …

Kinetics And Mechanisms Of Titanium Wire Oxidation, Tanmay P. Engineer

Boise State University Theses and Dissertations

The kinetics and mechanisms of oxidation of titanium wire were assessed using a large test matrix in Ar-20% O₂ at 800 to 1200°C, and N₂-20% O₂ at 1000°C, for 0.5 to 24 hours. The effects of geometry on oxidation were evaluated by investigating the behavior of six high purity Ti wires with diameters varying from 50 to 2000 μm, with an objective of producing hollow TiO₂ tubes.

Oxidation behavior was characterized by measuring oxide thicknesses and morphology by optical microscopy, and the phases were characterized using a combination of SEM and TEM. The kinetics was …

Electron Self-Trapping In Ge2 Se3 And Its Role In Ag And Sn Incorporation, Arthur H. Edwards, Kristy A. Campbell, Andrew C. Pineda

Electrical and Computer Engineering Faculty Publications and Presentations

We present a set of density functional theory (DFT) calculations on the electronic structure of Ag and Sn in Ge₂ Se₃ in a periodic model. We show that electron self-trapping is a persistent feature in the presence of many defects. Ag and Sn autoionize upon entering Ge₂ Se₃ becoming Ag₊ and Sn₂₊ , respectively, and the freed electrons self trap at the lowest energy site. Both Ag and Sn can substitute for Ge, and we present formation energies as a function of Fermi level that show that Sn can substantially alter the incorporation of …

Investigation Of The Noise Floor Of The Standard Piv Cross-Correlation Algorithm, Kyle L. Jones

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Particle image velocimetry (PIV) is a powerful measurement technique used to acquire instantaneous measurements of entire flow fields at a given instant in time. Quantifying the uncertainty and error in PIV is a critical part of realizing the full potential of PIV as a flow measurement technique.

The noise floor of PIV is the minimum amount of random error that can be achieved for a particular standard cross-correlation (SCC) algorithm. The noise floor of the SCC used by DaVis in correlating image pairs is explored. Two methods for creating image pairs for correlation are compared, namely pseudo image pairs and …

Hydraulic Modeling: Pipe Network Analysis, Trevor T. Datwyler

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Water modeling is becoming an increasingly important part of hydraulic engineering. One application of hydraulic modeling is pipe network analysis. Using programmed algorithms to repeatedly solve continuity and energy equations, computer software can greatly reduce the amount of time required to analyze a closed conduit system. Such hydraulic models can become a valuable tool for cities to maintain their water systems and plan for future growth. The Utah Division of Drinking Water regulations require cities to maintain hydraulic models of their culinary water systems, and before additional connections can be made to the water system, a licensed professional engineer must …

The Impact Of Freeway Traffic Conditions On In-Vehicle Exposure To Ultrafine Particulate Matter, Miguel A. Figliozzi, Alexander Y. Bigazzi

Civil and Environmental Engineering Faculty Publications and Presentations

There is evidence of adverse health impacts from human exposure to traffic-related ultrafine particulate matter pollution. As more commuters are spending a significant portion of their daily routine inside vehicles, it is increasingly relevant to study exposure levels to harmful pollutants inside the vehicle microenvironment. This study is one of the first research efforts to combine detailed freeway traffic data (at 20 s intervals) and in-vehicle ultrafine particulate (UFP) exposure data under varying vehicle ventilation conditions. Results show that due to negative correlation between traffic speed and density, traffic states have a small but significant impact on in-vehicle UFP concentrations, …

Evolution Of Ensemble Data Assimilation For Uncertainty Quantification Using The Particle Filter-Markov Chain Monte Carlo Method, Hamid Moradkhani, Caleb Matthew Dechant, Soroosh Sorooshian

Civil and Environmental Engineering Faculty Publications and Presentations

Particle filters (PFs) have become popular for assimilation of a wide range of hydrologic variables in recent years. With this increased use, it has become necessary to increase the applicability of this technique for use in complex hydrologic/land surface models and to make these methods more viable for operational probabilistic prediction. To make the PF a more suitable option in these scenarios, it is necessary to improve the reliability of these techniques. Improved reliability in the PF is achieved in this work through an improved parameter search, with the use of variable variance multipliers and Markov Chain Monte Carlo methods. …

Hybrid Plasmonic Nanoantennas: Fabrication, Characterization, And Application, Shengjie Zhai

UNLV Theses, Dissertations, Professional Papers, and Capstones

As optical counterpart of microwave antennas, plasmonic nanoantennas are important nanoscale devices for converting propagating optical radiation into confined/enhanced electromagnetic fields. Presently, nanoantennas, with a typical size of 200-500 nm, have found their applications in bio-sensing, bio-imaging, energy harvesting, and disease cure and prevention. With the device feature size of next generation IC goes down to 22 nm or smaller, and biological/chemical sensing reaches the Gene’s level, the sizes of the corresponding nanoantennas have to be scaled down to sub-100nm level. In the literature, these sub-100nm nanoantennas are referred as deep subwavelength nanoantennas as size of such miniaturized nanoantennas is …

Plasma Test On Industrial Diamond Powder In Hydrogen And Air For Fracture Strength Study, Rohit Asuri Sudharshana Asuri Sudharshana Chary

UNLV Theses, Dissertations, Professional Papers, and Capstones

Diamonds are the most precious material all over the world. Ever since their discovery, the desire for natural diamonds has been great; recently, the demand has steeply increased, leading to scarcity. For example, in 2010, diamonds worth $50 billion were marketed. This increased demand has led to discovering alternative sources to replace diamonds. The diamond, being the hardest material on earth, could be replaced with no other material except another diamond. Thus, the industrial or synthetic diamond was invented. Because of extreme hardness is one of diamond's properties, diamonds are used in cutting operations. The fracture strength of diamond is …

Laboratory Modeling Of Critical Hydraulic Conditions For The Initiation Of Piping, Mandie Swainston Fleshman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this research is to provide fundamental understanding of the piping phenomenon. This will lead to practical solutions to the critical hydraulic conditions for piping that account for soil properties, direction of flow, stress condition and exit face conditions. In current geotechnical engineering practice, these factors are generally not considered. The critical hydraulic gradient is assumed to be only a function of the soil buoyant unit weight. In recent analyses, laboratory experiments, and field observations indicate that piping can be initiated at gradients much lower than the values predicted by the current practice. The current practice may be …

A Multifunctional Solar Panel Antenna For Cube Satellites, Olutosin C. Fawole

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work presented the design of a single antenna structure that can perform the functions of about four antennas. The antenna is to be applied on a new kind of very tiny satellites. These satellites are called CubeSats. In contrast to an ordinary antenna that works at a single frequency band, the antenna designed will be able to work at about three different usable frequencies. In addition, it will be possible to make the waves emitted by the antenna to have multiple senses of rotation or no rotation at all. The multiple functional capability of the antenna will lead to …

Flow Characteristics Of Arced Labyrinth Weirs, Nathan A. Christensen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The need to accommodate larger reservoir discharge events has prompted the improvement or replacement of existing spillways. One possible spillway modification is the use of an in-reservoir arced labyrinth weir in place of a linear weir. Arced labyrinth weirs can increase crest length (more cycles) and have improved hydraulic efficiency in non-channelized approach flow applications, compared to traditional labyrinth weir applications.

In this study, arced labyrinth weir flow characteristics were observed for eleven different laboratory-scale model geometries at the Utah Water Research Laboratory. Rating (C_d vs. H_T/P) data and observations were recorded for each configuration, and discharge …

An Analysis Of Traffic Sign Performance For The Establishment Of A Maintenance Plan, Wesley Bill Boggs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For a variety of reasons both within and outside the control of transportation agencies, there is a higher frequency of fatalities during nighttime hours than during daytime hours. In an effort to enhance visual cues for nighttime motorists, the Federal Highway Administration (FHWA) established the minimum maintained retroreflectivity levels. This retroreflective mandate required agencies or public officials that have jurisdiction over a traffic sign population to implement maintenance methods that would ensure signs were performing at or above the minimum levels. Retroreflectivity is a unique type of reflection that distinguishes itself by reflecting light back in the direction of the …

Performance Characterization Of Complex Fuel Port Geometries For Hybrid Rocket Fuel Grains, Andrew Bath

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Extensive research in hybrid rocket motors has taken place at the department of Mechanical and Aerospace Engineering at USU (Utah State University) in the last several years. USU has one of the few facilities in the country capable of static-test firing rocket motors on-campus, which allows for fast-paced testing and development not available elsewhere. Research has involved investigating propulsion devices for a range of applications, including micro-satellite thrusters, hot-gas generators, and even jet-assisted takeoff kick motors. Hybrid motors have the advantage of safety over any other chemical propulsion. Since the fuel and oxidizer are stored seperately, they are relatively inert …

Examination Of Nonpoint Source Nutrient Export From A Snowfall-Dominated Watershed, Lindsey Deboer Carrigan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined nonpoint source pollution via tributaries to Pineview Reservoir. Since few literature values of export coefficients are available for snowfall-dominated watersheds such as Pineview, locally scaled rates were quantified using an upstream-downstream bracketing technique. Nitrogen and phosphorus grab samples were manually collected and discharge measurements were conducted during the annual study period. Additionally, high-frequency monitoring sensors that measured EC, temperature, turbidity, and water level were deployed at the up- and downstream sites to represent short-duration transport events and to examine watershed processes on a more representative time scale.

Daily nutrient loads were estimated from grab samples and flow …

Process Variation Aware Dram (Dynamic Random Access Memory) Design Using Block-Based Adaptive Body Biasing Algorithm, Satyajit Desai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Process variation can be defined as the deviation of process parameters from its nominal specifications. Variation is induced by several fundamental effects resulting from inaccuracies in the manufacturing equipment. It is a combination of systematic effects (e.g., lithographic lens aberrations) and random effects (e.g., dopant density fluctuations). The effect of process variation becomes particularly important at smaller process nodes, where the variation accounts for a major percentage of nominal length or width of the device. Process variations translate to a wide range in performance metrics of current designs. As technology scales, these die variations are getting larger, significantly affecting performance …

Transportation Network Resiliency: A Study Of Self-Annealing, Sunil Babu Pant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Disasters have the potential to hit any geographical location with or without warning. As such, it is desirable that transportation networks are able to withstand the adverse effect of disasters and maintain the normal functioning of all sectors of society. Resilient transportation networks are least affected by disruptions created by natural and manmade disasters and are still able function with an acceptable level of service. Such networks also have ability to return earlier from disrupted state to the normal functioning state. Resilience possessed by a transportation network measures the ability of networks to maintain functionality despite adverse conditions posed by …

Passive Ranging Using A Dispersive Spectrometer And Optical Filters, Jacob A. Martin

Theses and Dissertations

Monocular passive ranging using atmospheric oxygen absorption has been demonstrated in the past using an FTS. These instruments are very sensitive to vibration making them di cult to use on an airborne platform. This work focuses on whether passive ranging can be done with instruments that are easier to deploy. Two potential instruments are tested and compared: a diffraction grating spectrometer and optical filters. A grating spectrometer was able to estimate range to within 5% for a static solid rocket motor ring at a distance of 910 m using the NIR absorption band of oxygen. Testing at shorter ranges produced …

Hardware-Software Co-Design, Acceleration And Prototyping Of Control Algorithms On Reconfigurable Platforms, Desta Kumsa Edosa

UNLV Theses, Dissertations, Professional Papers, and Capstones

Differential equations play a significant role in many disciplines of science and engineering. Solving and implementing Ordinary Differential Equations (ODEs) and partial Differential Equations (PDEs) effectively are very essential as most complex dynamic systems are modeled based on these equations. High Performance Computing (HPC) methodologies are required to compute and implement complex and data intensive applications modeled by differential equations at higher speed. There are, however, some challenges and limitations in implementing dynamic system, modeled by non-linear ordinary differential equations, on digital hardware. Modeling an integrator involves data approximation which results in accuracy error if data values are not considered …

Post Processing Of Optically Recognized Text Using First Order Hidden Markov Model, Spandana Malreddy

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this thesis, we report on our design and implementation of a post processing system for Optically Recognized text. The system is based on first order Hidden Markov Model (HMM). The Maximum Likelihood algorithm is used to train the system with over 150 thousand characters. The system is also tested on a file containing 5688 characters. The percentage of errors detected and corrected is 11.76% with a recall of 10.16% and precision of 100%

Gravure Printability Of Indium Tin Oxide Nanoparticles On Glass And Pet Films For Applications In Printed Electronics, Dania Awni Alsaid

Dissertations

The advancements in the field of solution processable electro-active materials and their ability to be printed on different substrates have led to the evolution of printed electronics. In this field, electronic components are manufactured with conventional printing methods. Transparent electrodes made from indium tin oxide (ITO) are part of many electronic devices. Currently in industry, highly conductive ITO films are prepared by sputtering. The sputtering and then patterning of ITO films is a sophisticated process that consumes high energy, generates waste and produces films with limited flexibility. Therefore, there is a need to investigate processing methods for creating ITO films …

Phenomenological Modeling Of Image Irradiance For Non-Lambertian Surfaces Under Natural Illumination., Shireen Y. Elhabian

Electronic Theses and Dissertations

Various vision tasks are usually confronted by appearance variations due to changes of illumination. For instance, in a recognition system, it has been shown that the variability in human face appearance is owed to changes to lighting conditions rather than person's identity. Theoretically, due to the arbitrariness of the lighting function, the space of all possible images of a fixed-pose object under all possible illumination conditions is infinite dimensional. Nonetheless, it has been proven that the set of images of a convex Lambertian surface under distant illumination lies near a low dimensional linear subspace. This result was also extended to …

Small Specimen Test Techniques For Evaluating Radiation-Induced Changes In Mechanical Properties, Ellen Marie Rabenberg

Boise State University Theses and Dissertations

The mechanical properties of as-received and irradiated 304 stainless steel (304SS) were evaluated by the shear punch and miniature tensile techniques. A purpose of this study was to evaluate the shear punch technique itself, which is a less developed technique versus miniature tensile testing. This was accomplished in part by comparing yield and ultimate strengths obtained from shear punch and miniature tensile data. The tests were further correlated by evaluating the mechanical properties of aluminum 6061 and Inconels 600 and 718. A linear relationship was observed between the shear strength and tensile strength data, providing a correlation between the two …