Mechanical Engineering Commons^™

College Of Engineering Senior Design Competition Spring 2019, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Wearable Devices For Single-Cell Sensing And Transfection, Lingqian Chang, Yu-Chieh Wang, Faheem Ershad, Ruiguo Yang, Cunjiang Yu, Yubo Fan

Department of Mechanical and Materials Engineering: Faculty Publications

Wearable healthcare devices are mainly used for biosensing and transdermal delivery. Recent advances in wearable biosensors allow for long-term and real-time monitoring of physiological conditions at a cellular resolution. Transdermal drug delivery systems have been further scaled down, enabling wide selections of cargo, from natural molecules (e.g., insulin and glucose) to bioengineered molecules (e.g., nanoparticles). Some emerging nanopatches show promise for precise single-cell gene transfection in vivo and have advantages over conventional tools in terms of delivery efficiency, safety, and controllability of delivered dose. In this review, we discuss recent technical advances in wearable micro/nano devices with unique capabilities or …

Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi S. Patel

University Scholar Projects

Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.

Objective: Here, we establish a biodegradable, piezoelectric …

Development Of A Sonically Powered Biodegradable Nanogenerator For Bone Regeneration, Avi Patel

Honors Scholar Theses

Background: Reconstruction of bone fractures and defects remains a big challenge in orthopedic surgery. While regenerative engineering has advanced the field greatly using a combination of biomaterial scaffolds and stem cells, one matter of difficulty is inducing osteogenesis in these cells. Recent works have shown electricity’s ability to promote osteogenesis in stem cell lines when seeded in bone scaffolds; however, typical electrical stimulators are either (a) externally housed and require overcomplex percutaneous wires be connected to the implanted scaffold or (b) implanted non-degradable devices which contain toxic batteries and require invasive removal surgeries.

Objective: Here, we establish a biodegradable, piezoelectric …

Listener Evaluation Of Common Drum Recording And Mixing Techniques, Tucker W. Arbuthnot

Student Theses

This thesis explored whether listeners could perceive the differences between samples recorded and mixed according to methods reported by the so-called popular audio press and samples that did not utilize those methods. The three recording methods were: aligning multiple tracks to achieve a coherent phase relationship, microphone selection, and the style of recording. The three mixing methods were: inverting the bottom snare drum microphone to match the top snare drum microphone, having a pre-delay time on a reverb that matched the tempo of the sample, and routing the room microphones to the drummer’s perspective. ABX listening tests, preference surveys, and …

Physical Controllers Vs. Hand-And-Gesture Tracking: Evaluation Of Control Schemes For Vr Audio Mixing, Justin Bennington

Student Theses

Alternative control schemes for affecting the characteristics of audio signals have been designed and evaluated within the audio research community. The medium of virtual reality (VR) presents a unique method of sound source visualization using a headset which displays a virtual environment to the user, allowing users to directly control sound sources with minimal intermediary interference with a variety of different controllers. In order to provide insight into the design and evaluation of VR systems for audio mixing, the differences in subject preference between physical controllers and hand-and-gesture detection controls were investigated. A VR audio mixing interface was iteratively developed …

Mid-Side To X/Y Equivalence: Turning Microphone Theory Into Practice, Brent T. Hauer

Student Theses

The mathematical transformation of the Mid-Side microphone array (M-S) to stereophonic left and right outputs results in an equivalent coincident microphone configuration (X/Y). The output pattern of the combined mid (M) and side (S) signals can be altered by manipulating the polar pattern of the mid (M) microphone and by adjusting the ratio between the M and side (S) microphones. This study investigated the technical and perceptual attributes of equivalent M-S and X/Y patterns in order to determine the consistency of the theoretical with the practical application. A simulated jazz sextet was recorded using a selection of M-S, and their …

Geospatial Energy Potential And Life Cycle Assessment Of Nearshore Oscillating Water Column Systems, Aleks Siemenn, Marie-Odile Fortier

CURCE Annual Undergraduate Conference

Oscillating Water Column (OWC) systems are an iteration of terminator ocean energy technology which generate electrical energy from turbine torque induced by the compression of air in a chamber from changing water level height. OWCs are a well-established technology, however, there have been no studies to date which quantify the life cycle environmental impacts of these systems in a geographic context. The goal of this study is to optimally size an OWC system for selected New England coastline sites and then assess the environmental impacts of the varying system sizes.

An OWC system is optimally sized when the volume of …

Subscale Mars Colonization Mission, Cameron J. Lamack, James Lumsden, Sean Nevin, Donner Schoeffler, Riley Evers, Alexandra Poulakos, Skyler Tan, Anthony Keba, Siraj Zaman, Ali Altamimi, Anthony Modica

Honors Thesis

The team will compete in the SAE (Society of Automotive Engineers) Aero Design West Advanced Class competition, held 5-7th April 2019 in Van Nuys, California. The team will work to develop, through research, design, optimizational trade studies, and manufacturing, a system for the deployment of parasitic aircraft, as well as payload. The system will consist of a primary fixed-wing aircraft, parasitic autonomous gliders, a real-time altitude data acquisition system, as well as both static and releasable payload. The deployable gliders must navigate autonomously to a targeting area on the ground without any on-board propulsion. The releasable payload, which will consist …

Intrinsic Coating Morphology Modulates Acute Drug Transfer In Drug-Coated Balloon Therapy, Gary H. Chang, Dara A. Azar, Chimera Lyle, Vipul C. Chitalia, Tarek Shazly, Vijaya B. Kolachalama

Faculty Publications

The hallmark of drug-coated balloon (DCB) therapy for the treatment of peripheral vascular disease is that it allows for reopening of the narrowed lumen and local drug delivery without the need for a permanent indwelling metal implant such as a stent. Current DCB designs rely on transferring drugs such as paclitaxel to the arterial vessel using a variety of biocompatible excipients coated on the balloons. Inherent procedural challenges, along with limited understanding of the interactions between the coating and the artery, interactions between the coating and the balloon as well as site-specific differences, have led to DCB designs with poor …

Ole Miss Engineer 2019

Ole Miss Engineer

No abstract provided.

Transferring Power Through A Magnetic Couple, Nickolas Cruz Villalobos Jr.

Senior Theses

Properties of several working magnetic coupled rotors have been measured and their performance compared to theoretical models. Axial magnetic couplers allow rotors to work within harsh environments, without the need for seals, proper alignment, or overload protection on a motor. The influence of geometrical parameters, such as distance from the center of the rotors, polarity arrangement, and the number of dipole pairs were experimentally tested. These results can be used to improve rotor designs, to increase strength and efficiency.

Exploring The Electrical Properties Of Twisted Bilayer Graphene, William Shannon

Senior Theses

Two-dimensional materials exhibit properties unlike anything else seen in conventional substances. Electrons in these materials are confined to move only in the plane. In order to explore the effects of these materials, we have built apparatus and refined procedures with which to create two-dimensional structures. Two-dimensional devices have been made using exfoliated graphene and placed on gold contacts. Their topography has been observed using Atomic Force Microscopy (AFM) confirming samples with monolayer, bilayer, and twisted bilayer structure. Relative work functions of each have been measured using Kelvin Probe Force Microscopy (KPFM) showing that twisted bilayer graphene has a surface potential …

Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller

Graduate Theses and Dissertations

Materials with features at the nanoscale can provide unique mechanical properties and increased functionality when included as part of a nanocomposite. This dissertation utilizes computational methods at multiple scales, including molecular dynamics (MD) and density functional theory (DFT), and the coupled atomistic and discrete dislocation multiscale method (CADD), to predict the mechanical properties of nanocomposites possessing nanomaterials that are either 1-D (carbyne chains), 2-D (graphene sheets), or 3-D (Al/amorphous-Si core-shell nanorod).

The MD method is used to model Ni-graphene nanocomposites. The strength of a Ni-graphene nanocomposite is found to improve by increasing the gap between the graphene sheet and a …

Fault Adaptive Workload Allocation For Complex Manufacturing Systems, Charlie B. Destefano

Graduate Theses and Dissertations

This research proposes novel fault adaptive workload allocation (FAWA) strategies for the health management of complex manufacturing systems. The primary goal of these strategies is to minimize maintenance costs and maximize production by strategically controlling when and where failures occur through condition-based workload allocation.

For complex systems that are capable of performing tasks a variety of different ways, such as an industrial robot arm that can move between locations using different joint angle configurations and path trajectories, each option, i.e. mission plan, will result in different degradation rates and life-expectancies. Consequently, this can make it difficult to predict when a …

The Role Of Inter-Particle Behavior In Iron Oxide Nanoparticle Induction Heating, Hayden Seth Carlton

Graduate Theses and Dissertations

Due to their multi-functional nature, iron oxide nanoparticles present themselves in a myriad of scientific disciplines, but perhaps the most interesting property of these nanomaterials can be seen in their immense thermal response under the influence of alternating magnetic fields. Currently popularized as an alternative cancer treatment through localized hyperthermia, iron oxide nanoparticle induction heating presents an interesting physical phenomenon that distinguishes itself from macroscopic induction heating. Understanding how a single spherical particle behaves is relatively simple and remains well documented; however, magnetic interactions of a single particle often extend over many length scales, affecting numerous neighboring particles in the …

Motor Control Systems Analysis, Design, And Optimization Strategies For A Lightweight Excavation Robot, Austin Jerold Crawford

Graduate Theses and Dissertations

This thesis entails motor control system analysis, design, and optimization for the University of Arkansas NASA Robotic Mining Competition robot. The open-loop system is to be modeled and simulated in order to achieve a desired rapid, yet smooth response to a change in input. The initial goal of this work is to find a repeatable, generalized step-by-step process that can be used to tune the gains of a PID controller for multiple different operating points. Then, sensors are to be modeled onto the robot within a feedback loop to develop an error signal and to make the control system self-corrective …

Production Of Liquid Fuels From Natural Gas: Simulation Of Synthesis Gas And Fischer-Tropsch Reactors, Saiedeh Arabi Bolaghi

Mechanical and Aerospace Engineering Dissertations - Archive

Gas to Liquid (GTL) processes chemically convert natural gas to valuable liquid hydrocarbon products. The GTL process considered in this research is comprised of three phases: 1) syngas production, 2) Fischer-Tropsch synthesis (FTS), and 3) product separation. This study focuses on the simulation and optimization of a GTL process to convert natural gas to more valuable liquid fuels. In syngas production, steam methane reforming (SMR) is typically used although it requires an external heat source due to the endothermic nature of the reaction. In addition, the SMR approach produces syngas with a hydrogen to carbon monoxide ratio that is not …

Gasdynamic Phenomena And Propulsive Performance Of Pulse Detonation Engines, James T. Pearce

Mechanical and Aerospace Engineering Dissertations - Archive

The pulsed detonation engine (PDE) is an advanced propulsion system that makes use of intermittent detonations to provide thrust. In recent decades, the PDE has been at the center of various propulsion research efforts focused on practical implementation of a reliable detonation-based engine for aerospace propulsion applications. However, many design challenges remain to be solved due to the PDEs unsteady operating characteristics. In particular, the unsteady nature of the thrust chamber flow field inherent to the PDE operation makes the design of nozzles aimed at adequately expanding the burned detonation products especially difficult. In order to address this design challenge, …

Onboard Payload Mass Estimation And Electric Propulsion Modeling For Multicopters With Application In Unmanned Aerial Systems, Abel Martinez Martinez Martinez

Mechanical and Aerospace Engineering Theses - Archive

Unmanned vehicles are the future. The aim of the future online retailers, delivery and transportation companies would be air delivery using unmanned aerial vehicles. Multicopters are becoming rapidly famous because they o er a relatively easy-to-fly platform that is also very stable, and their mechanical simplicity. The possibility of estimating the weight of the multicopter in real time is really useful. A weight estimation system that could be implemented in multicopters with cable suspended payloads without using any extra sensors is presented in this thesis. The weight estimation system uses a functional relationship that correlates Pulse Position Modulation (PPM) signal …

Experimental Analysis For Optimization Of Thermal Performance Of A Server In Single Phase Immersion Cooling, Pravin Ashok Shinde

Mechanical and Aerospace Engineering Theses - Archive

Liquid immersion cooling of servers in synthetic dielectric fluids is an emerging technology which offers significant cooling energy saving and increased power densities for data centers. A noteworthy advantage of using immersion cooling is high heat dissipation capacity which is roughly 1200 times greater than air. Other advantages of dielectric fluid immersion cooling include high rack density, better server performance, even temperature profile, reduction in noise. The enhanced thermal properties of oil lead to the considerable saving of both upfront and operating cost over traditional methods. In this study, a server is completely submerged in a synthetic dielectric fluid. Experiments …

Onboard Payload Mass Estimation And Electric Propulsion Modeling For Multicopters With Application In Unmanned Aerial Systems, Abel Martinez Martinez

Mechanical and Aerospace Engineering Theses - Archive

Unmanned vehicles are the future. The aim of the future online retailers, delivery and transportation companies would be air delivery using unmanned aerial vehicles. Multicopters are becoming rapidly famous because they o er a relatively easy-to-fly platform that is also very stable, and their mechanical simplicity. The possibility of estimating the weight of the multicopter in real time is really useful. A weight estimation system that could be implemented in multicopters with cable suspended payloads without using any extra sensors is presented in this thesis. The weight estimation system uses a functional relationship that correlates Pulse Position Modulation (PPM) signal …

Computational Analysis For Thermal Optimization Of Server For Single - Phase Immersion Cooling, Dhruvkumar Vimalkumar Gandhi

Mechanical and Aerospace Engineering Theses - Archive

Complete immersion of servers in synthetic dielectric fluids is rapidly becoming a popular technique to minimize the energy consumed by data centers for cooling purposes. In general, immersion cooling offers noteworthy advantages over conventional air-cooling methods as synthetic dielectric fluids have high heat dissipation capacities which are roughly about 1200 times greater than air. Other advantages of dielectric fluid immersion cooling include even temperature profile on chips, reduction in noise and addressing reliability and operational enhancements like whisker formation and electro-chemical migration. Nevertheless, lack of data published and availability of long-term reliability data on immersion cooling is insufficient which makes …

Electroextraction Across Droplet-Droplet Interface, Subhadeep Chakraborti

Mechanical and Aerospace Engineering Theses - Archive

Extraction of analytes from solvents is a crucial part of many medical, clinical, industrial and refinery processes. It is required for preconcentration of analytes into other solvents, purification of solvents and detection of harmful or toxic molecules. One of the very important methods of extraction in microfluidics is liquid-liquid extraction (LLE). LLE involves the use of two immiscible liquids for diffusion of analytes across the interface. Recently there has been a growing interest in the coupling of external electric field with LLE to enhance the extraction of charged analytes. This has led to the birth of a new extraction method …

Effect Of Dielectric Inter-Layer In Performance Of The Multi-Functional Material In Mechanical, Thermal And Environmental Loading Conditions, Rauhon Ahmed Shaik

Mechanical and Aerospace Engineering Theses - Archive

The demand for Electrical power storage devices for space shuttle, aircraft, car, bus and marine vehicles increased a great deal to have a greener and safer world. Decades of research has been done on development of light weight and high-performance energy storage devices such as batteries and structural capacitors. The use of structural capacitors can solve the high-performance energy storage requirement with no dead weight and also gives a strong structure. However, these heterogeneous materials experience different thermal expansions across the dielectric and electrodes inter layers due to which the energy storage capacity and mechanical performance evolve over time. Hence, …

Methodology To Develop Artificial Neural Network Based Control Strategies For Multiple Air-Cooling Units In A Raised Floor Data Center, Vibin Shalom Simon

Mechanical and Aerospace Engineering Theses - Archive

A data center consists of a hierarchy of systems with dedicated control algorithms dictating their operational states. We could say, there exists an ensemble of dynamical systems, each executing a control task, while the global objective is to drive the overall system to an optimum i.e. minimum total operational power at desired rack inlet temperatures. The dynamics of the Information Technology Equipment (ITE) workload and the cooling provisioning is non-linear in spatial and temporal parameter space. Data-driven modelling is one method to realistically model such non-linear dynamics and make predictions that are necessary for improved control design of the cooling …

Numerical And Experimental Study On Turbulence Production Of A Selected Mode Of Streamwise Vortex Interaction In Supersonic Flow, Davide Viganó

Mechanical and Aerospace Engineering Dissertations - Archive

The development of effective mixing strategies of air/fuel mixtures in supersonic flows has been the subject of a significant body of research for the last 60 years due to the hindering effects of compressibility. Particular attention has been focused on the introduction of streamwise vortices as a way to enhance molecular mixing both in terms of added source for hydrodynamic instabilities on classical shear-layer flows as well as for transverse jet configurations, aero-ramps and hypermixers. However, a large portion of fundamental knowledge for these complex flows is still missing. This work is centered on a numerical and experimental study of …

Characterization Of 3d Printed Pla With The Help Of Mechanical, Di-Electric And X-Ray Diffraction Techniques, Sai Sri Nidhi Munaganuru

Mechanical and Aerospace Engineering Theses - Archive

Additive manufacturing (AM) revolutionized many industries, i.e., Automotive, Biomedical, Aerospace and Defense. As opposed to traditional manufacturing methods, a part is manufactured layer by layer from 3D CAD models in AM. Though the vision of AM is impressive, there are many challenges that are hindering the widespread use of these complex parts. One of the main challenges is its strength that varies with different manufacturing parameters. We are going to investigate the effect of build parameters on the mechanical, electrical and crystalline properties of the additively manufactured heterogeneous material system. The goal of the thesis is to find a correlation …

Probabilistic Risk Assessment And The Path Planning Of Safe Task-Aware Autonomous Resilient Systems (Staars), Uluhan Cem Kaya

Mechanical and Aerospace Engineering Theses - Archive

Recent advancements on the unmanned systems manifest the potential of these technologies to impact our daily life. In particular, the unmanned aircraft systems (UAS) become ordinary for people in almost any area from aerial photography to emergency responses, from agricultural services to even autonomous deliveries. Increased autonomy and advancements in low-cost high-computing technologies made these compact autonomous solutions accessible to any party with ease. Easiness and affordability to access these systems accelerated the innovations and the novel ideas for the solution of diverse real-life problems. Despite its benefits, however, this widespread availability also resulted in the safety and regulatory concerns …

Simulation Modelling Of Thermal Runaway Propagation In Li Ion Batteries, Dhananjay Mishra

Mechanical and Aerospace Engineering Theses - Archive

Li Ion batteries are highly engineered systems which have become part and parcel of our daily lives. Safety of these systems has been in jeopardy ever since they were created. Mechanical abuse, shot circuit, overcharging or unfavorable working conditions can lead to catastrophic repercussions which might destroy complete battery pack. Previous works have investigated this problem, but many important aspects of design characteristics were left folded. This work not only investigates behavior of a single cell under adverse conditions but also lays emphasis on important factors such as thermal conductivity of the medium and cell gaps in a pack of …