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Trajectory Analysis For Driving Safety Quantification, Michael I. Chang
Trajectory Analysis For Driving Safety Quantification, Michael I. Chang
UNLV Theses, Dissertations, Professional Papers, and Capstones
In order to evaluate the efficacy of the skid recovery exercise in the Driver’s Edge teenage driving program, a process is established to determine the trajectories of vehicles from recorded videos, compare them in terms of similarity through dynamic time warping (DTW), and then analyze the similarity measurements to assess whether the program has a significant effect on driving ability by repeated measures analysis of variance (rANOVA). The video is analyzed by Harris corner detection and Lucas-Kanade optical flow method to ascertain the vehicle trajectories. A homography is then estimated to translate coordinates from video into real-world. The instructor and …
High-Yield Bioinspired Atmospheric Water Capture Through Hydrogels, Yiwei Gao
High-Yield Bioinspired Atmospheric Water Capture Through Hydrogels, Yiwei Gao
UNLV Theses, Dissertations, Professional Papers, and Capstones
Water scarcity is a global issue affecting billions of people, and atmospheric water harvesting (AWH) technology has been identified as a potential solution. However, existing single-material AWH approaches have limited water harvesting yields due to alternated water capture, storage, and release stages, and only function within a high relative humidity range. In my doctoral research project, we developed a bio-inspired, hydrogel-based multi-layer AWH approach that allows for segregated capture, storage, and release stages, and is envisioned to have higher daily water harvesting efficiency even in low-humidity areas. My research began with understanding the relations between hydrogel mechanical stiffness, hydraulic permeability, …
Non-Destructive Means Of Predicting Masonry Prism Strength Using Ultrasonic Pulse Velocity (Upv), Connor J. Barlow
Non-Destructive Means Of Predicting Masonry Prism Strength Using Ultrasonic Pulse Velocity (Upv), Connor J. Barlow
UNLV Theses, Dissertations, Professional Papers, and Capstones
Current ASTM standards call for grouted masonry prisms to be tested for compressive strength at 28-days to ensure compliance with the structural design. In the event of failing tests, the subject samples may require redesign or reconstruction which can pose problems due to ongoing development around and including the prisms between the time of placement and obtaining test results. The purpose of this research is to determine if the use of ultrasonic pulse velocity (UPV) testing can be utilized to determine a correlation between prism composite strength of the masonry prism with ultrasound readings as to provide preliminary means of …
Enhanced Iot-Based Electrocardiogram Monitoring System With Deep Learning, Jian Ni
Enhanced Iot-Based Electrocardiogram Monitoring System With Deep Learning, Jian Ni
UNLV Theses, Dissertations, Professional Papers, and Capstones
Due to the rapid development of computing and sensing technologies, Internet of Things (IoT)-based cardiac monitoring plays a crucial role in providing patients with cost-efficient solutions for long-term, continuous, and pervasive electrocardiogram (ECG) monitoring outside a hospital setting. In a typical IoT-based ECG monitoring system, ECG signals are picked up by sensors located on the edge, and then uploaded to the remote cloud servers. ECG interpretation is performed for the collected ECGs in the cloud servers and the analysis results can be made instantly available to the patients as well as their healthcare providers.In this dissertation, we first examine the …
An Investigation Of Soft Electrohydraulic Actuators: Theory, Characterization, And Conceptual Applications, Alexandrea Washington
An Investigation Of Soft Electrohydraulic Actuators: Theory, Characterization, And Conceptual Applications, Alexandrea Washington
UNLV Theses, Dissertations, Professional Papers, and Capstones
Electroactive polymer (EAP) materials are a novel soft electromechanical device that exploits the inherent electrical and mechanical advantages of flexible polymer materials. Within this groundbreaking field there are various actuator and sensor devices that have been developed for a variety of applications, from medical devices to artificial biological systems. This research focuses on electrohydraulic actuators, which are comprised of a flexible conductive medium, a dielectric fluid, and a compliant film material to encapsulate the dielectric fluid. This specific study centers around the electrohydraulic EAP actuator known as the Hydraulically Amplified Self-Healing Electrostatic (HASEL) actuator, first introduced by the Keplinger group …
Nexuscapes: A Landscape Approach For A Transdisciplinary Water-Energy-Food Nexus Decision-Making Process, Fortino Acosta
Nexuscapes: A Landscape Approach For A Transdisciplinary Water-Energy-Food Nexus Decision-Making Process, Fortino Acosta
UNLV Theses, Dissertations, Professional Papers, and Capstones
This study develops a reliable transdisciplinary framework for complex ecological and social systems by characterizing, mapping, typifying, assessing, and testing enhanced water-energy-food nexus scenarios under critical time constraints, specialized skills, or sensitive data accessibility. Detached management of limited essential resources like fresh water, reliable energy from renewable sources, and nutritious food can jeopardize regional economies and governance. Using a novel landscape approach, this study recommends a decision-making the framework focused on the circular economy that induces collaboration among diverse sectors and brings strategic coordination, specificity, and magnitude to the proposed solutions. The study elaborates on a decision-making tool that integrates …
Dynamic Surface Tension Of Surfactants Through Separation Of Diffusion And Dilation Effects, Brandon Ortiz
Dynamic Surface Tension Of Surfactants Through Separation Of Diffusion And Dilation Effects, Brandon Ortiz
UNLV Theses, Dissertations, Professional Papers, and Capstones
Surfactants are biphilic monomers that adsorb to interfaces and have the ability to reduce interfacial tension. From this reduction in interfacial tension, surfactants are able to function as emulsifiers, detergents, and wetting agents among a variety of other things. Despite their ubiquity surfactants and surfactant behaviors, in particular those in highly dynamic environments, are not yet well characterized. In these environments, surfactants undergo significant distortions to droplet, bubble, and foam geometries which induce changes to the surface tension. This establishes a need to understand how surfactants respond to distortions of geometry through diffusion and dilational effects. To address this need, …
Effects Of Particle Size And Replacement Proportion Of Post-Consumer Glass In Concrete, Negasi Gebremichael
Effects Of Particle Size And Replacement Proportion Of Post-Consumer Glass In Concrete, Negasi Gebremichael
UNLV Theses, Dissertations, Professional Papers, and Capstones
Concrete, next to water, is the most used material (Gagg, 2014), which consumes natural or manufactured aggregates and resource-intensive cement. Concrete is also a more wasteful construction material than timber and steel. Depleting the natural resource due to aggregate extraction and the environmental unfriendliness of cement production have left the construction industry with no choice. Reducing waste, reusing, or recycling can help conserve natural resources. In this regard, the construction industry constantly seeks full or partial replacement of concrete aggregates and cement with recycled material. Glass is a candidate for replacing the three major components: cement, fine aggregate, and coarse …
A Control Integrated Circuit For A Hysteretic Flyback Power Converter, Armani Alvarez
A Control Integrated Circuit For A Hysteretic Flyback Power Converter, Armani Alvarez
UNLV Theses, Dissertations, Professional Papers, and Capstones
This Thesis reports the design, simulation, and layout of a switching power supply controller chip for a fly-back switching power supply. The controller chip was designed using ON’s Semiconductor C5 process. The resulting switching power supply using the controller chip consists of using various off-chip components such as a power MOSFET, transformer, and capacitors. The main components used in the integrated circuit include a bandgap reference voltage circuit which outputs a reference voltage of 1.25V, a ring oscillator having a nominal frequency of 5MHz, a high-gain comparator, and a buffer that can drive a 5pF capacitor. Under normal simulation conditions …
Application Of Experimentally Calibrated Numerical Models For Prediction Of Composite Masonry Prism Strength, James Bristow
Application Of Experimentally Calibrated Numerical Models For Prediction Of Composite Masonry Prism Strength, James Bristow
UNLV Theses, Dissertations, Professional Papers, and Capstones
The composite masonry prism test is a common laboratory test to determine the compressive strength of a set of masonry prisms (f’mt) to verify that the composite masonry prism assembly, and more importantly, the constituent materials, are providing adequate strength. While constructing masonry structures, the subcontractors, designers, and inspectors rarely provide continuous supervision or inspection of the construction process. Accordingly, verification of grout mix design, mixed proportions, proper installation of blocks, placement of mortar, dimensions of joints, etc. are more traditionally performed on a periodic basis instead. However, through the use and review of the composite masonry prism test results, …
Towards The Electronic Response Of Carbon-Based Van Der Waals Heterostructures In A Diamond Anvil Cell, George Thomas Foskaris
Towards The Electronic Response Of Carbon-Based Van Der Waals Heterostructures In A Diamond Anvil Cell, George Thomas Foskaris
UNLV Theses, Dissertations, Professional Papers, and Capstones
The nanoscale regime of materials has been at the forefront of research and interest in condensed matter physics for many years. In a merger of the fields of two-dimensional (2D) materials and high pressure physics, we present an investigation of the electronic response of carbon-based, van der Waals (vdW) heterostructures in a diamond anvil cell (DAC). Combining these fields presents us with the ability to study the characteristics of such systems both optically, and through electrical transport. Properties such as conductance, band structure, and layer number are considered. The samples in this study are assembled using exfoliation and stacking techniques …
Automated Approach For The Enhancement Of Scaffolding Structure Monitoring With Strain Sensor Data, Sayan Sakhakarmi
Automated Approach For The Enhancement Of Scaffolding Structure Monitoring With Strain Sensor Data, Sayan Sakhakarmi
UNLV Theses, Dissertations, Professional Papers, and Capstones
Construction researchers have made a significant effort to improve the safety of scaffolding structures, as a large proportion of workers are involved in construction activities requiring scaffolds. However, most past studies focused on design and planning aspects of scaffolds. While limited studies investigated scaffolding safety during construction, they are limited to simple cases only with limited failure modes and simple scaffolds. In response to this limitation, this study aims to develop an automated scaffold monitoring approach capable of monitoring large scaffolds. Accordingly, this study developed an automated scaffold safety monitoring framework that leverages sensor data collected from a scaffold, scaffold …
Measuring Impacts And Vibrations On A Volumetric Modular House During Transportation, Seung Ho Song
Measuring Impacts And Vibrations On A Volumetric Modular House During Transportation, Seung Ho Song
UNLV Theses, Dissertations, Professional Papers, and Capstones
The U.S. construction industry is experiencing an increase in demand for further implementation of modular construction due to the significant productivity and project cost-reducing benefits it provides. However, there exist challenges with the modular method, and many of them are well covered by previous studies, except for the effects of transportation-induced impact/vibration on volumetric modules. A previous study examined the effects of transportation-induced impact/vibration on a timber-framed module and identified some valuable findings. But, it did not explore other types of modules, height considerations, and the differences in the magnitude of impact/vibration due to different module maneuvers on the road. …
Identification Of Factors Contributing To Traffic Crashes By Analysis Of Text Narratives, Cristian D. Arteaga-Sanchez
Identification Of Factors Contributing To Traffic Crashes By Analysis Of Text Narratives, Cristian D. Arteaga-Sanchez
UNLV Theses, Dissertations, Professional Papers, and Capstones
The fatalities, injuries, and property damage that result from traffic crashes impose a significant burden on society. Current research and practice in traffic safety rely on analysis of quantitative data from crash reports to understand crash severity contributors and develop countermeasures. Despite advances from this effort, quantitative crash data suffers from drawbacks, such as the limited ability to capture all the information relevant to the crashes and the potential errors introduced during data collection. Crash narratives can help address these limitations, as they contain detailed descriptions of the context and sequence of events of the crash. However, the unstructured nature …
Developing A Hands-On Class Exercise For Modular Construction, 3d Design, And 4d Schedule, Kyle A. Kithas
Developing A Hands-On Class Exercise For Modular Construction, 3d Design, And 4d Schedule, Kyle A. Kithas
UNLV Theses, Dissertations, Professional Papers, and Capstones
Modular construction shows promise as a viable alternative to stick-built construction. A major challenge with the widespread adoption of modular construction is the construction industry’s focus on minimizing risk and defaulting to the comfort and familiarity of stick-built construction. This pattern can be broken through an educational paradigm shift in the way architecture, engineering, and construction are taught in school. Integrating modular construction education into higher education is presented to increase the future adoption of modular construction and expand the comfort zones of future industry leaders. This thesis proposes that current curriculum be augmented to teach the modular approach in …
Mechanoelectrical Behavior In Polyvinyl Chloride (Pvc) Based Soft Polymer Gel Smart Sensors For Soft Robotic Applications, Justin Neubauer
Mechanoelectrical Behavior In Polyvinyl Chloride (Pvc) Based Soft Polymer Gel Smart Sensors For Soft Robotic Applications, Justin Neubauer
UNLV Theses, Dissertations, Professional Papers, and Capstones
Polyvinyl chloride (PVC) gels are a class of electroactive polymer that contain a PVC-based polymeric lattice and various amounts of plasticizer. PVC and plasticizer are industrially available and are commonly used in a wide range of applications including cable insulation, flexible hosing, and healthcare equipment. There are many plasticizer types available, some being extremely biocompatible with implementations in food-safe applications and even food additives for human consumption. Plasticizer weakly bonds to the long polymerized chains of the polymer lattice decreasing the modulus of the composite material. By adding excessive amounts of plasticizer, the bonding sites of these long carbon chains …
Development And Application Of A Safety Index For Transit Stops: A Case Study From Las Vegas, Nevada, Rithesh Shivuni
Development And Application Of A Safety Index For Transit Stops: A Case Study From Las Vegas, Nevada, Rithesh Shivuni
UNLV Theses, Dissertations, Professional Papers, and Capstones
This research developed a methodology to evaluate safety proximate to transit stops through a Safety Index, identified key factors associated with fatal crashes proximate to bus transit stops, and illustrated the applications of these using a case study based on the Las Vegas metropolitan area in Nevada, USA. The methodology is based on motor vehicle crashes that involve pedestrians recorded in the proximity of transit stops, and the severity of the crash outcomes. It focused on crashes which involved pedestrians that occurred within walking distances of individual transit stops. The severity of the crash outcomes was classified based on the …
Enhancements To Nuclear Thermal Propulsion Rockets, Kimberly Gonzalez
Enhancements To Nuclear Thermal Propulsion Rockets, Kimberly Gonzalez
UNLV Theses, Dissertations, Professional Papers, and Capstones
Nuclear thermal rocket propulsion has been proposed as a highly efficient technology for space vehicles traveling from earth orbit to the moon, Mars, and other locations in the solar system. With twice the performance of a chemical rocket, nuclear thermal propulsion (NTP) uses the thrust produced by heating hydrogen gas within a thermal nuclear reactor where the exhaust is then passed through a de Laval nozzle to produce supersonic flow. NTP engines were the subject ofthe NERVA experiments at the Nevada Test Site in the 1970’s, and they produced a specific impulse of up to 900 seconds which is almost …
Hyperspectral Image Analysis Of Food For Nutritional Intake, Shirin Nasr Esfahani
Hyperspectral Image Analysis Of Food For Nutritional Intake, Shirin Nasr Esfahani
UNLV Theses, Dissertations, Professional Papers, and Capstones
The primary object of this dissertation is to investigate the application of hyperspectral technology to accommodate for the growing demand in the automatic dietary assessment applications. Food intake is one of the main factors that contribute to human health. In other words, it is necessary to get information about the amount of nutrition and vitamins that a human body requires through a daily diet. Manual dietary assessments are time-consuming and are also not precise enough, especially when the information is used for the care and treatment of hospitalized patients. Moreover, the data must be analyzed by nutritional experts. Therefore, researchers …
Towards High-Efficient Broadband Omnidirectional Light-Trapping: Discrepancy-Assisted 2d/3d Deterministic Quasi-Random Nanostructure Design, Optimization, And Fabrication, Yihong Zhao
UNLV Theses, Dissertations, Professional Papers, and Capstones
Recently, nano-scaled surface decoration has brought significant advancement and exciting new possibilities to light management. Numerous nanostructure patterns have been explored, wherein the quasi-random nanostructures (QRNs) present a promising path in manipulating light to increase the photon flux over the broadband spectra for optical (e.g., photovoltaic) devices. However, due to the infinite number of QRNs, it is difficult to directly design and fabricate the exact QRN pattern as desired to achieve the optimized light-trapping capability. To overcome this obstacle, we 1) digitize the traditional continuous QRNs into meshes and then map the meshes to binary matrices, which can be deterministically …
Mobile 3d Printing Of Rail Track Surface For Rapid Repai, Ershad Mortazavian
Mobile 3d Printing Of Rail Track Surface For Rapid Repai, Ershad Mortazavian
UNLV Theses, Dissertations, Professional Papers, and Capstones
The frequent replacement of worn rails on tracks brings an immense economic burden on the railroad industry, and also causes significant interruptions to railroad operation. Restoration of worn rails via additive manufacturing, i.e., 3D printing, can considerably reduce the associated maintenance costs.The scope of this dissertation is to utilize metal additive manufacturing (AM) technology to repair worn rails that are used in the U.S. railway transportation system (e.g. 75-lb/yd light transit rails, or 136-lb/yd heavy freight rails). More specifically, this study aims to understand the interactive mechanisms between the deposited materials and the high-carbon rail steel to identify and alleviate …
Application Of Lanthanides In Wastewater Treatment And Water Reuse, George William Kajjumba
Application Of Lanthanides In Wastewater Treatment And Water Reuse, George William Kajjumba
UNLV Theses, Dissertations, Professional Papers, and Capstones
Much of the world’s population feed on grains (wheat, rice, and corn). Corn is as sensitive as it is productive. This thirsty, fast-growing plant goes into thermal shock in drought. In 2014, California lost over $2.2 billion in crop production due to drought. The Horn of Africa (in 2011) and Sahel (in 2012) faced humanitarian disasters due to food and water scarcity. The higher frequency of climate change and the erratic nature of rain, combined with underlying economic and social vulnerabilities, has meant that food and water scarcity is here to stay. To improve food and water scarcity, water reclamation …
Carbon Fiber Coil Spring Characterization And Manufacturing, Cooper Madrazo
Carbon Fiber Coil Spring Characterization And Manufacturing, Cooper Madrazo
UNLV Theses, Dissertations, Professional Papers, and Capstones
Helical coil springs are used in many mechanical design applications including industrial machines, devices, and vehicle suspension systems. It is desirable to minimize the weight of vehicle suspension systems as this can improve performance and handling. Most vehicle suspension coil springs are made from solid steel alloys or other metallic materials. Significant weight savings could be achieved if the metallic material were replaced by high performance fiber reinforced polymer composites. However, the coil spring geometry is a difficult manufacturing challenge for composite materials. The goal of this thesis was to investigate efficient and low-cost manufacturing methods to produce light-weight polymer …
Development Of Uav-Based Rail Track Geometry Irregularity Monitoring And Measuring Platform Empowered By Artificial Intelligence, Lihao Qiu
UNLV Theses, Dissertations, Professional Papers, and Capstones
Rail tracks need to be consistently monitored and inspected for problems associated with rust, deformation, and cracks that, at their worst, can cause catastrophic train derailments. Many non-destructive testing approaches have been explored and extensively utilized to help inspect rails’ health, but most of them require intensive human power and/or heavy sensor systems (e.g. total stations, manual/car-mounted trolly, etc.) that are not efficient or convenient to cover a long range of rails and may interfere with the normal operation of trains.In light of the rapid development of unmanned aerial systems/vehicles (UAS’s/UAVs) and high definition photographic and optical distance measuring sensors, …
A Performance Guide For Four Songs By Francisco Mignone, Amanda Mara Rizzotto Vidal Pessoa
A Performance Guide For Four Songs By Francisco Mignone, Amanda Mara Rizzotto Vidal Pessoa
UNLV Theses, Dissertations, Professional Papers, and Capstones
The scope of this document is to demonstrate the richness and diversity to be found in the art song genre from countries outside of the standard repertoire, specifically focusing on the Brazilian composer Francisco Mignone. The purpose of this document is to provide performance practice guidelines for four selected pieces by Francisco Mignone: No Meio do Caminho (1938), Pregão (1947), Si eu sei o que é saudade (1976), and Valsa-Vocalise (1972). They exemplify expressions of Brazilian national identity through the music selected. Furthermore, it provides a brief background on the composer and his compositional style phases, and context for the …
Efficient Networks-On-Chip Communication Support Solutions For Deep Neural Network Acceleration, Binayak Tiwari
Efficient Networks-On-Chip Communication Support Solutions For Deep Neural Network Acceleration, Binayak Tiwari
UNLV Theses, Dissertations, Professional Papers, and Capstones
The increasing popularity of deep neural network (DNN) applications demands high computing power and efficient hardware accelerator architectures. DNN accelerators use a large number of processing elements (PEs) and on-chip memory for storing weights and other parameters. A significant challenge is faced when designing a many-core DNN accelerator to handle the data movement between the processing elements. As the communication backbone of a DNN accelerator, networks-on-chip (NoC) plays an important role in supporting various dataflow patterns and enabling processing with communication parallelism in a DNN accelerator. However, the widely used mesh-based NoC architectures inherently cannot efficiently support many-to-one (gather) and …
Predicting The Progression Of Diabetes Mellitus Using Dynamic Plantar Pressure Parameters, Mathew Sunil Varre
Predicting The Progression Of Diabetes Mellitus Using Dynamic Plantar Pressure Parameters, Mathew Sunil Varre
UNLV Theses, Dissertations, Professional Papers, and Capstones
Introduction: Diabetic peripheral neuropathy is one of the common complications of type-2 diabetes mellitus (DM). Changes in the intrinsic plantar tissue coupled with repetitive mechanical loads and loss of sensation may lead to foot related complications (skin break down, ulcerations, and amputations) in persons with neuropathy if left untreated. The purpose of this dissertation was to stratify individuals with pre-diabetes, diabetes with and without neuropathy using dynamic plantar pressure parameters during walking, using machine learning algorithms.Methods: Plantar pressure data was collected from one hundred participants during walking with pressure measuring insoles fixed between the feet and thin socks. Simultaneously high-definition …
Towards Highly Sensitive Capacitance Measurements Of A Quantum Anomalous Hall Phase In Van Der Waal Heterostructures, Kayla Cerminara
Towards Highly Sensitive Capacitance Measurements Of A Quantum Anomalous Hall Phase In Van Der Waal Heterostructures, Kayla Cerminara
UNLV Theses, Dissertations, Professional Papers, and Capstones
One of the pioneering achievements in condensed matter physics of the 20th century is the observation of the quantum Hall e↵ect (QHE) in which the Hall resistance in a two-dimensional (2D) sample takes on quantized values in the presence of a strong perpendicular magnetic field. The precise quantization of the hall resistance to one part in a billion has provided a practical, worldwide resistance standard. A long-standing goal has been to realize a similar state of matter but without the need of a strong quantizing magnetic field. The quantum anomalous Hall e↵ect (QAHE) is such a state that is predicted …
Radiomic Features To Predict Overall Survival Time For Patients With Glioblastoma Brain Tumors Based On Machine Learning And Deep Learning Methods, Lina Chato
UNLV Theses, Dissertations, Professional Papers, and Capstones
Machine Learning (ML) methods including Deep Learning (DL) Methods have been employed in the medical field to improve diagnosis process and patient’s prognosis outcomes. Glioblastoma multiforme is an extremely aggressive Glioma brain tumor that has a poor survival rate. Understanding the behavior of the Glioblastoma brain tumor is still uncertain and some factors are still unrecognized. In fact, the tumor behavior is important to decide a proper treatment plan and to improve a patient’s health. The aim of this dissertation is to develop a Computer-Aided-Diagnosis system (CADiag) based on ML/DL methods to automatically estimate the Overall Survival Time (OST) for …
Factors Affecting Hotel Recommendation: Before The Covid-19 Pandemic And After The Reopening, Boran Kim
Factors Affecting Hotel Recommendation: Before The Covid-19 Pandemic And After The Reopening, Boran Kim
UNLV Theses, Dissertations, Professional Papers, and Capstones
During the COVID-19 pandemic, numerous people lost their lives, and a lot of industries were affected. The hospitality industry was especially affected due to social distancing, travel restrictions, and safety issues. During that time, not only did customers' expectations change but their recommendation of hotels to friends and colleagues also changed. The current study used five factors (i.e., cleanliness, location, room, service, and value) to discover which factors were affecting hotel recommendation before the COVID-19 pandemic and after the reopening. This study used secondary data (online surveys) from one of the well-known integrated resorts located in the western United States. …