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Full-Text Articles in Engineering

Material Handling With Embodied Loco-Manipulation, Jean Chagas Vaz Dec 2021

Material Handling With Embodied Loco-Manipulation, Jean Chagas Vaz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Material handling is an intrinsic component of disaster response. Typically, first responders, such as firefighters and/or paramedics, must carry, push, pull, and handle objects, facilitating the transportation of goods. For many years, researchers from around the globe have sought to enable full-sized humanoid robots to perform such essential material handling tasks. This work aims to tackle current limitations of humanoids in the realm of interaction with common objects such as carts, wheelbarrows, etc. Throughout this research, many methods will be applied to ensure a stable Zero Moment Point (ZMP) trajectory to allow a robust gait while loco-manipulating a cart. The …


A Human-Embodied Drone For Dexterous Aerial Manipulation, Dongbin Kim Dec 2021

A Human-Embodied Drone For Dexterous Aerial Manipulation, Dongbin Kim

UNLV Theses, Dissertations, Professional Papers, and Capstones

Current drones perform a wide variety of tasks in surveillance, photography, agriculture, package delivery, etc. However, these tasks are performed passively without the use of human interaction. Aerial manipulation shifts this paradigm and implements drones with robotic arms that allow interaction with the environment rather than simply sensing it. For example, in construction, aerial manipulation in conjunction with human interaction could allow operators to perform several tasks, such as hosing decks, drill into surfaces, and sealing cracks via a drone. This integration with drones will henceforth be known as dexterous aerial manipulation.

Our recent work integrated the worker’s experience into …


Global 3d Radiation Hydrodynamic Simulations Of Proto-Jupiter’S Convective Envelope, Zhaohuan Zhu, Yan-Fei Jiang, Hans Baehr, Andrew N. Youdin, Philip J. Armitage, Rebecca G. Martin Nov 2021

Global 3d Radiation Hydrodynamic Simulations Of Proto-Jupiter’S Convective Envelope, Zhaohuan Zhu, Yan-Fei Jiang, Hans Baehr, Andrew N. Youdin, Philip J. Armitage, Rebecca G. Martin

Physics & Astronomy Faculty Research

The core accretion model of giant planet formation has been challenged by the discovery of recycling flows between the planetary envelope and the disc that can slow or stall envelope accretion. We carry out 3D radiation hydrodynamic simulations with an updated opacity compilation to model the proto-Jupiter’s envelope. To isolate the 3D effects of convection and recycling, we simulate both isolated spherical envelopes and envelopes embedded in discs. The envelopes are heated at given rates to achieve steady states, enabling comparisons with 1D models. We vary envelope properties to obtain both radiative and convective solutions. Using a passive scalar, we …


The “East Side” Of Las Vegas: A Latinx Historical Framework, Nathalie Martinez Aug 2021

The “East Side” Of Las Vegas: A Latinx Historical Framework, Nathalie Martinez

Spectra Undergraduate Research Journal

Spanish heritage speakers in the United States are a reflection of everchanging linguistic and sociolinguistic pressures that result in myriad varieties across generations. This paper provides a preliminary historical framework to fill this gap of linguistic knowledge in the Spanish-speaking community of Las Vegas, Nevada. The goals were two-fold: (1) highlight the largest Spanish-speaking communities in Las Vegas and (2) explore the significance of the East Side in the history of the Latinx population of Las Vegas. Through the analysis of oral histories and historical works, the investigation highlights the Mexican, Salvadoran, and Cuban populations of Las Vegas and their …


Qualitative Review Of Educational Interventions For Improving Physical Activity Behaviors In Older Asian Americans In The United States, Raisa Kabir, Manoj Sharma, Sayeda Tazim Zaidi, Chia-Liang Dai Aug 2021

Qualitative Review Of Educational Interventions For Improving Physical Activity Behaviors In Older Asian Americans In The United States, Raisa Kabir, Manoj Sharma, Sayeda Tazim Zaidi, Chia-Liang Dai

Spectra Undergraduate Research Journal

Physical activity (PA) provides numerous health benefits and minimizes chronic diseases and mental health issues, especially in older adults. The national survey data indicated that only 27.3% to 44.3% of older adults meet the recommended PA guidelines of 150 to 300 minutes/ week. There is limited data on PA behavior among older Asian American (AA) adults as very few to no local/national surveys have targeted these marginalized subgroups. This comprehensive review aims to identify existing PA intervention strategies and to update current knowledge on the effectiveness of these interventions to improve PA behavior among aging AA in the US. The …


The Future Of The Live Entertainment Tax In Southern Nevada, Katie M. Gilbertson Aug 2021

The Future Of The Live Entertainment Tax In Southern Nevada, Katie M. Gilbertson

Spectra Undergraduate Research Journal

The Live Entertainment Tax (LET) in Nevada generated nearly one billion dollars during the 2019-2020 fiscal year. LET revenue all goes to the State General Fund, even though 97 percent of LET revenue is generated in Clark County. Nevada is experiencing an economic crisis, particularly in the tourism industry. Solutions from various fields suggest the best way to boost the local economy is to reinvest revenue in its original county. One policy solution Nevada policymakers should consider is to carve out a percentage of revenue generated by the LET to return directly back to Clark County to revitalize tourism.


Diabetes Mellitus Affects Working Memory, Dylone C. Braganza, Emmanuel Flores, Lauren A. Crew, Ryan A. Wirt, Andrew A. Ortiz, Adam M. Mcneela, Jefferson W. Kinney, James M. Hyman Aug 2021

Diabetes Mellitus Affects Working Memory, Dylone C. Braganza, Emmanuel Flores, Lauren A. Crew, Ryan A. Wirt, Andrew A. Ortiz, Adam M. Mcneela, Jefferson W. Kinney, James M. Hyman

Spectra Undergraduate Research Journal

Alzheimer’s disease (AD) degrades the brain’s ability to remember, think, and carry out tasks. The exact cause is not known, but several risk factors have been identified, including diabetes mellitus (DM). DM causes elevated blood sugar levels due to reduced insulin production in the pancreas. The linkage between elevated glucose levels and the behavioral impairments are not fully understood, which was the focus of this study. Rats were trained to alternate directions in a maze to receive a reward on consecutive trials. After training, five rats were injected with streptozotocin (STZ), which induces hyperglycemia by injuring pancreatic beta cells. Three …


A Timeline Of Discovery And Current Research On Primary Open-Angle Glaucoma And Emergence Of Potentially Permanent Treatment Solutions, Yonosuke Dejesus, Guadalupe Moreno Ceballos Aug 2021

A Timeline Of Discovery And Current Research On Primary Open-Angle Glaucoma And Emergence Of Potentially Permanent Treatment Solutions, Yonosuke Dejesus, Guadalupe Moreno Ceballos

Spectra Undergraduate Research Journal

This research examines the timeline of the discovery and research of Primary Open-Angle Glaucoma (POAG). By reviewing the literature on genetic and molecular mechanisms, we aim to emphasize a long-term treatment solution (iSTENT) to mitigate intraocular pressure (IOP) related to POAG etiology and disease progression. POAG is a multifactorial, autosomal dominant, adult-onset eye disease wherein the optic nerve cells become damaged due to a buildup of excess aqueous humor, resulting in increased IOP. Consequently, POAG leads to progressive loss of peripheral vision and is the leading cause of blindness in the US. Due to the multifactorial nature of glaucoma’s inheritance …


Racial Profiling: Understanding The Practice Of Stop-And-Frisk In New York City, Lisa Ly Aug 2021

Racial Profiling: Understanding The Practice Of Stop-And-Frisk In New York City, Lisa Ly

Spectra Undergraduate Research Journal

Racial profiling has become a prominent issue in modern policing today. Instead of being based on individual suspicion, racial profiling embodies a belief that people of color are continuously singled out by the police for scrutiny and harassment. Policies and procedures make the Black community vulnerable to police discrimination and racial profiling. Floyd et al. v. City of New York et al. (2013) declared that the New York Police Department’s (NYPD) practice of stop-and-frisk was racially profiling Black civilians. This study sought (1) to determine if the NYPD post-Floyd is still engaging in racial profiling towards Black civilians; and (2) …


Forecasting Pedestrian Trajectory Using Deep Learning, Arsal Syed Aug 2021

Forecasting Pedestrian Trajectory Using Deep Learning, Arsal Syed

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this dissertation we develop different methods for forecasting pedestrian trajectories. Complete understanding of pedestrian motion is essential for autonomous agents and social robots to make realistic and safe decisions. Current trajectory prediction methods rely on incorporating historic motion, scene features and social interaction to model pedestrian behaviors. Our focus is to accurately understand scene semantics to better forecast trajectories. In order to do so, we leverage semantic segmentation to encode static scene features such as walkable paths, entry/exits, static obstacles etc. We further evaluate the effectiveness of using semantic maps on different datasets and compare its performance with already …


Rotten With Prediction, Serena Raquel Hicks Aug 2021

Rotten With Prediction, Serena Raquel Hicks

UNLV Theses, Dissertations, Professional Papers, and Capstones

This project focuses on the relationship between religion and technology as it is portrayed in Science Fiction (SF). This thesis explores the SF genre rhetorically by examining the 2002 movie Minority Report (MR), which signaled the importance of surveillance and the need to predict future crimes following 9/11. The events of 9/11 played a significant role in post 9/11 SF films, which reflect and critique our communal and cultural values. 9/11 created a new relationship between the U.S justice system, predictive technologies (PTs), and data gathering. Through the Bush Doctrine of “preemptive action,” the U.S government attempted to use Dataism, …


Real-Time Pm10 Emission Rates From Paved Roads By Measurement Of Concentrations In The Vehicle's Wake Using On-Board Sensors Part 2. Comparison Of Scamper, Traker™, Flux Measurements, And Ap-42 Silt Sampling Under Controlled Conditions, Dennis R. Fitz, Kurt Bullimer, Vic Etyemezian, Hampden D. Kuhns, John A. Gillies, George Nikolich, David E. James, Rodney Langston, Russell S. Merle Jr. May 2021

Real-Time Pm10 Emission Rates From Paved Roads By Measurement Of Concentrations In The Vehicle's Wake Using On-Board Sensors Part 2. Comparison Of Scamper, Traker™, Flux Measurements, And Ap-42 Silt Sampling Under Controlled Conditions, Dennis R. Fitz, Kurt Bullimer, Vic Etyemezian, Hampden D. Kuhns, John A. Gillies, George Nikolich, David E. James, Rodney Langston, Russell S. Merle Jr.

Civil and Environmental Engineering and Construction Faculty Research

Representative soil was evenly applied to an 800-m section of road surface. The test area was of sufficient length to allow for measurement at constant speeds of up to 72 km hr−1. SCAMPER and TRAKER™ mobile measurement vehicles made repeated test runs while an instrumented tower measured upwind-downwind horizontal PM10 flux. AP-42 methods were used to collect silt samples and calculate PM10 emission factors. Both silt loadings and vehicle speeds were varied during the experiment. Street sweeping the as-found roadway showed an initial rise in PM10 emission rates. Both TRAKER and SCAMPER measured rapid decay of PM10 emission rates after …


Plasma Aerodynamics: Experimental Quantification Of The Lift Force Generated On An Airfoil Using Plasma Actuation To Estimate Power Requirements In Small Uav Applications, Getachew Ashenafi May 2021

Plasma Aerodynamics: Experimental Quantification Of The Lift Force Generated On An Airfoil Using Plasma Actuation To Estimate Power Requirements In Small Uav Applications, Getachew Ashenafi

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research addressed the amount of electric power required to induce specific changes in lift force using a NACA 2127 airfoil with a chord length of ~28 mm, connected to a micro load cell, in a wind tunnel of 103 square centimeter cross-section. A DBD plasma actuator supplied by a ZVS driven high voltage pulsed DC circuit, operating at a frequency of 17.4 kHz, was utilized for voltages of up to 5000 V. Two configurations of electrode gapping were compared to determine the efficient use of power. The configuration with a gap of ~1 mm between the upstream and downstream …


Dynamic Analysis Of A Microgrid Powered With An Inverter And Machine-Based Distributed Resources, Brandon William Blackstone May 2021

Dynamic Analysis Of A Microgrid Powered With An Inverter And Machine-Based Distributed Resources, Brandon William Blackstone

UNLV Theses, Dissertations, Professional Papers, and Capstones

The proliferation of renewable distributed energy resources, particularly photovoltaic (PV) power systems, and the increasing need for a reliable power supply has led to the concept of microgrids, a mini-grid that consists of locally connected power generation units and needs, able to operate connected or disconnected from the utility grid, using controlled and coordinated methods to provide for the users of the microgrid the best possible conditions for their needs. The main technical issues facing microgrids include some of the following, seamless transition from stand-alone to utility grid connected operation, how to preserve frequency and voltage stability, and provide the …


A Hyperelastic Porous Media Framework For Ionic Polymer-Metal Composites And Characterization Of Transduction Phenomena Via Dimensional Analysis And Nonlinear Regression, Zakai J. Olsen May 2021

A Hyperelastic Porous Media Framework For Ionic Polymer-Metal Composites And Characterization Of Transduction Phenomena Via Dimensional Analysis And Nonlinear Regression, Zakai J. Olsen

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ionic polymer-metal composites (IPMC) are smart materials that exhibit large deformation in response to small applied voltages, and conversely generate detectable electrical signals in response to mechanical deformations. The study of IPMC materials is a rich field of research, and an interesting intersection of material science, electrochemistry, continuum mechanics, and thermodynamics. Due to their electromechanical and mechanoelectrical transduction capabilities, IPMCs find many applications in robotics, soft robotics, artificial muscles, and biomimetics. This study aims to investigate the dominating physical phenomena that underly the actuation and sensing behavior of IPMC materials. This analysis is made possible by developing a new, hyperelastic …


Degradation Of Antibiotics In Aqueous Phase Using Pms Catalytic Decomposition With Zero-Valent Iron Nanoparticles Immobilized In Sba-15, Ahdee Bluma Zeidman May 2021

Degradation Of Antibiotics In Aqueous Phase Using Pms Catalytic Decomposition With Zero-Valent Iron Nanoparticles Immobilized In Sba-15, Ahdee Bluma Zeidman

UNLV Theses, Dissertations, Professional Papers, and Capstones

Zero-valent iron nanoparticles (nZVI) have been studied as an option for soil remediation and water treatment for many years. The capability of nZVI to produce oxidation/reduction processes, depending on the reaction conditions, has attracted great interest with their major drawback being reactivity loss through agglomeration. The loss in nZVI surface area has been reported to be prevented through immobilization onto a porous media (e.g., SBA-15, MCM-41, or zeolites). In this work, a mesoporous silica structure (SBA-15) is used as an nZVI supporting material to enhance its reactivity and promote peroxymonosulfate (PMS) catalytic decomposition for the degradation of antibiotics in aqueous …


Spike Nozzle Design For Use In Nanosat Orbital Maneuvering, Drew Nemeth Apr 2021

Spike Nozzle Design For Use In Nanosat Orbital Maneuvering, Drew Nemeth

Undergraduate Research Symposium Podium Presentations

Annular spike nozzle engines have long been the holy grail of rocket engine design, promising superior performance in a smaller footprint when compared to conventional bell nozzles. However, flaws inherent to the design of spike nozzles have prevented widespread adoption and testing. As a result, research on potential applications has been quite sparse. This project aims to further spike nozzle research by investigating rarely tested materials that literature suggests have potential for use in a spike nozzle design. The goal of the overall research project is to examine 3D printed polycarbonate component longevity under conditions representative of a small satellite …


Renewable Energy Generation And Ghg Emission Reduction Potential Of A Satellitewater Reuse Plant By Using Solar Photovoltaics And Anaerobic Digestion, Jonathan R. Bailey, Saria Bukhary, Jacimaria R. Batista, Sajjad Ahmad Feb 2021

Renewable Energy Generation And Ghg Emission Reduction Potential Of A Satellitewater Reuse Plant By Using Solar Photovoltaics And Anaerobic Digestion, Jonathan R. Bailey, Saria Bukhary, Jacimaria R. Batista, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Wastewater treatment is a very energy-intensive process. The growing population, increased demands for energy and water, and rising pollution levels caused by fossil-fuel-based energy generation, warrants the transition from fossil fuels to renewable energy. This research explored the energy consumption offset of a satellite water reuse plant (WRP) by using solar photovoltaics (PVs) and anaerobic digestion. The analysis was performed for two types of WRPs: conventional (conventional activated sludge system (CAS) bioreactor with secondary clarifiers and dual media filtration) and advanced (bioreactor with membrane filtration (MBR)) treatment satellite WRPs. The associated greenhouse gas (GHG) emissions were also evaluated. For conventional …


Computation And Data Driven Discovery Of Topological Phononic Materials, Jiangxu Li, Jiaxi Liu, Stanley A. Baronett, Mingfeng Liu, Lei Wang, Ronghan Li, Yun Chen, Dianzhong Li, Qiang Zhu, Xing Qiu Chen Feb 2021

Computation And Data Driven Discovery Of Topological Phononic Materials, Jiangxu Li, Jiaxi Liu, Stanley A. Baronett, Mingfeng Liu, Lei Wang, Ronghan Li, Yun Chen, Dianzhong Li, Qiang Zhu, Xing Qiu Chen

Physics & Astronomy Faculty Research

© 2021, The Author(s). The discovery of topological quantum states marks a new chapter in both condensed matter physics and materials sciences. By analogy to spin electronic system, topological concepts have been extended into phonons, boosting the birth of topological phononics (TPs). Here, we present a high-throughput screening and data-driven approach to compute and evaluate TPs among over 10,000 real materials. We have discovered 5014 TP materials and grouped them into two main classes of Weyl and nodal-line (ring) TPs. We have clarified the physical mechanism for the occurrence of single Weyl, high degenerate Weyl, individual nodal-line (ring), nodal-link, nodal-chain, …


Effect Of Heat Treatment On Microstructure And Hardness Of A Worn Rail Repaired Using Laser Powder Deposition, Ershad Mortazavian, Zhiyong Wang, Hualiang Teng Jan 2021

Effect Of Heat Treatment On Microstructure And Hardness Of A Worn Rail Repaired Using Laser Powder Deposition, Ershad Mortazavian, Zhiyong Wang, Hualiang Teng

Mechanical Engineering Faculty Research

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 laser powder deposition (LPD) can considerably reduce the associated maintenance costs. This study was focused on the use of LPD to repair the worn profile of a standard U.S. rail. The microstructure of the 304L stainless steel deposits with a minimum hardness of 85 HRB was composed of austenite, δ-ferrite, and sigma. Micropores were dispersed throughout the deposit, and microcracks were found at the rail-deposition interface. The pearlitic rail substrate …