Mechanical Engineering Commons^™

An Investigation On The Influences Of Radial Head Hemiarthroplasty Stem Fixation Techniques On Articular Mechanics, Jakub Szmit

Electronic Thesis and Dissertation Repository

Radial head hemiarthroplasty design has been extensively studied with a focus on utilizing the geometrical characteristics of the native radial dish as a guide of implant placement and design. Although implant design has been studied, optimal radial head implant fixation technique remains unknown. This thesis focused on the effect of stem fit on radiocapitellar contact mechanics, using both finite element and experimental bench-top approaches. Additionally, investigation into the impact of varus/valgus malalignment of the radial head in both the native state and following hemiarthroplasty was conducted. It was found that loose fitting a smooth stem axisymmetric radial head implant through …

Dynamic Body-Weight Support To Boost Rehabilitation Outcomes In Patients With Non-Traumatic Spinal Cord Injury: An Observational Study, Justin P. Huber, Lumy Sawaki

Neurology Faculty Publications

BACKGROUND: Dynamic body-weight support (DBWS) may play an important role in rehabilitation outcomes, but the potential benefit among disease-specific populations is unclear. In this study, we hypothesize that overground therapy with DBWS during inpatient rehabilitation yields greater functional improvement than standard-of-care in adults with non-traumatic spinal cord injury (NT-SCI).

METHODS: This retrospective cohort study included individuals diagnosed with NT-SCI and undergoing inpatient rehabilitation. All participants were recruited at a freestanding inpatient rehabilitation hospital. Individuals who trained with DBWS for at least three sessions were allocated to the experimental group. Participants in the historical control group received standard-of-care (i.e., no DBWS). …

Review Of Γ’ Rafting Behavior In Nickel-Based Superalloys: Crystal Plasticity And Phase-Field Simulation, Zhiyuan Yu, Xinmei Wang, Fuqian Yang, Zhufeng Yue, James C. M. Li

Chemical and Materials Engineering Faculty Publications

Rafting is an important phenomenon of the microstructure evolution in nickel-based single crystal superalloys at elevated temperature. Understanding the rafting mechanism and its effect on the microstructure evolution is of great importance in determining the structural stability and applications of the single crystal superalloys. Phase-field method, which is an excellent tool to analyze the microstructure evolution at mesoscale, has been gradually used to investigate the rafting behavior. In this work, we review the crystal plasticity theory and phase-field method and discuss the application of the crystal plasticity theory and phase-field method in the analysis of the creep deformation and microstructure …

The Economics Of Classroom 3-D Printing Of Open-Source Digital Designs Of Learning Aids, Nicole Gallup, Joshua M. Pearce

Michigan Tech Publications

While schools struggle financially, capital for purchasing physical learning aids is often cut. To determine if costs could be reduced for learning aids, this study analyzed classroom-based distributed digital manufacturing using 3-D printing of open-source learning aid designs. Learning aid designs are analyzed in detail for their economic viability considering printing and assembly costs with purchased components and compared to equivalent or inferior commercial products available on Amazon. The results show current open-source 3-D printers are capable of manufacturing useful learning aids and that doing so provides high economic savings in the classroom. Overall, the average learning aid would save …

Improvement Of Light Intensity And Efficiency Of N-Zno/Nio/P-Gan Heterojunction-Based White Light Emitting Diodes Using Micro-/Nanolens Array, Apurba Adhikary, Md Shamim Ahsan, Md Mahbub Hossain, Md Bipul Hossain, S. H. Shah Newaz, Farid Ahmed, Ik-Bu Sohn

Manufacturing & Industrial Engineering Faculty Publications and Presentations

Our study proposes a technique to enhance light extraction efficiency of light emitting diodes (LEDs) by incorporating various micro-/nanolens arrays (MNLAs) on the substrate layer, which in turn increases the external quantum efficiency (EQE) of the LEDs. To simulate the LEDs, we utilized the finite difference time domain method. To achieve a white LED, we inserted a thin layer of NiO at the interface between the n-type ZnO and the p-type GaN. The basic n-ZnO/NiO/p-GaN heterojunction-based LED exhibited an EQE of 10.99% where the effective refractive index of the LED structure was 1.48. The EQE was further increased by engraving …

Sustainable Drug Release From Polycaprolactone Coated Chitin‑Lignin Gel Fibrous Scaffolds, Turdimuhammad Abdullah, Kalamegam Gauthaman, Azadeh Mostafavi, Ahmed Alshahrie, Numan Salah, Pierfrancesco Morganti, Angelo Chianese, Ali Tamayol, Adnan Memic

Department of Mechanical and Materials Engineering: Faculty Publications

Non-healing wounds have placed an enormous stress on both patients and healthcare systems worldwide. Severe complications induced by these wounds can lead to limb amputation or even death and urgently require more effective treatments. Electrospun scaffolds have great potential for improving wound healing treatments by providing controlled drug delivery. Previously, we developed fibrous scaffolds from complex carbohydrate polymers [i.e. chitin-lignin (CL) gels]. However, their application was limited by solubility and undesirable burst drug release. Here, a coaxial electrospinning is applied to encapsulate the CL gels with polycaprolactone (PCL). Presence of a PCL shell layer thus provides longer shelf-life for the …

Machine Learning Augmentation Micro-Sensors For Smart Device Applications, Mohammad H. Hasan

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Novel smart technologies such as wearable devices and unconventional robotics have been enabled by advancements in semiconductor technologies, which have miniaturized the sizes of transistors and sensors. These technologies promise great improvements to public health. However, current computational paradigms are ill-suited for use in novel smart technologies as they fail to meet their strict power and size requirements. In this dissertation, we present two bio-inspired colocalized sensing-and-computing schemes performed at the sensor level: continuous-time recurrent neural networks (CTRNNs) and reservoir computers (RCs). These schemes arise from the nonlinear dynamics of micro-electro-mechanical systems (MEMS), which facilitates computing, and the inherent ability …

Laser Powder Bed Fusion Of Nitihf High-Temperature Shape Memory Alloy: Effect Of Process Parameters On The Thermomechanical Behavior, Mohammadreza Nematollahi, Guher P. Toker, Keyvan Safaei, Alejandro Hinojos, S. Ehsan Saghaian, Othmane Benafan, Michael J. Mills, Haluk E. Karaca, Mohammad Elahinia

Mechanical Engineering Faculty Publications

Laser powder bed fusion has been widely investigated for shape memory alloys, primarily NiTi alloys, with the goal of tailoring microstructures and producing complex geometries. However, processing high temperature shape memory alloys (HTSMAs) remains unknown. In our previous study, we showed that it is possible to manufacture NiTiHf HTSMA, as one of the most viable alloys in the aerospace industry, using SLM and investigated the effect of parameters on defect formation. The current study elucidates the effect of process parameters (PPs) on the functionality of this alloy. Shape memory properties and the microstructure of additively manufactured Ni-rich NiTiHf alloys were …

Rf Studies Of Soot And Ammonia Loadings On A Combined Particulate Filter And Scr Catalyst, Shreyans Sethia, David Kubinski, Hans Nerlich, Jeffrey Naber

Michigan Tech Publications

Modern diesels employ a particulate filter (DPF) to reduce soot emissions. Additionally, the selective catalytic reduction (SCR) of NOx by NH3 stored on the SCR catalyst reduces NOx emissions. In some vehicles the functions of these aftertreatment components are combined in the SDPF, a DPF having a SCR washcoat. The RF resonant method has been shown to be an alternative tool for measuring the DPF's soot loading and the SCR's NH3 loading. For both applications, the transmitted electromagnetic signal between antennae placed on either side of the catalyst change with loading. Here we report the influence of the RF signal …

Grow Local Manufacturing Along Us/Mexico Border Region For An Integrated Supply Chain In The Post Covid-19 Era, Jianzhi Li

Manufacturing & Industrial Engineering Faculty Publications and Presentations

The current coronavirus disease pandemic, plus the strong movement of manufacturing reshoring, provide a unique opportunity for many US regions to grow local manufacturers. This technical note attempts to review the current situation and trend in US manufacturing. We then discuss challenges and necessary steps, such as asset mapping, required to grow local suppliers. Suggestions are then made to support growing local suppliers along the US/Mexico border region.

Annual Simulation Of Photovoltaic Retrofits Within Existing Parabolic Trough Concentrating Solar Powerplants, Nipun Goel, Hannah O'Hern, Matthew Orosz, Todd Otanicar

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Solar power for electricity production comes from either photovoltaics or concentrating solar power plants. The former has seen rapid growth and expansion due to the rapid fall in global prices, while the latter has seen moderate growth due to ability to cheaply store thermal energy for later use. Hybridization, or combining photovoltaics with concentrating solar power represents a potential way for lowering cost while enabling long term storage. Over 5 GW of capacity exist worldwide using parabolic trough style technology for concentrating solar power which presents a unique option for optimization in the form of a photovoltaic retrofit. While it …

Evaluation Of A Bulge Reduction Technology For Corrugated Fiberboard Containers Under Static Compression, Daan Peleman, Jay Singh, Koushik Saha, S. Roy

Journal of Applied Packaging Research

This research examines the effect of top-to-bottom static compression load on the bulge of RSC containers. The study compares a control regular slotted container (RSC) constructed with corrugated fiberboard to tape-reinforced designs. The bulge reduction, achieved using various tape placements and conditioning environments, were measured. Currently, no research on the effect of reinforcement tape towards reduction in the out-of-plane displacement (bulging) of the corrugated fiberboard panels has been undertaken. Samples related to four different container designs, varying by presence, quantity and the position of the reinforcement tape on the vertical panels, were tested and analyzed. The study involved the use …

Obtaining Mechanical Shock Fragility Statistics For Simple Stochastic Cushioning Design., Shogo Horiguchi, Katsuhiko Saito

Journal of Applied Packaging Research

Proper cushioning to prevent product damage and over-packaging must consider the mechanical-shock fragility of the product. Furthermore, improved cushioning design can be achieved by performing stochastic cushioning design using mechanical-shock fragility statistics and transport hazard statistics. However, many samples are required to obtain mechanical-shock fragility statistics from standard testing comprising critical velocity change tests and critical-acceleration tests (the “conventional method”). In many cases, the required number of samples cannot be prepared. Thus, this research is designed to develop testing methods requiring half the number of samples of the conventional method. Thus far, "test method with one sample" has been developed …

Experimental Investigation Of Liquid Height Estimation And Simulation Verification Of Bolt Tension Quantification Using Surface Acoustic Waves, Hani Alhazmi

USF Tampa Graduate Theses and Dissertations

In this dissertation, two separate applications that are related to surface acoustic waves in a solid media are presented. The first study concerns simulating and validating an experimentally study for quantifying the bolt tension in the bolted joints using the surface acoustic wave. The second study experimentally investigates measuring the level of a liquid existing on a solid surface via surface acoustic waves and exploring the effect of liquid existence on the propagation of surface acoustic waves over the solid surface.

Quantifying bolt tension and ensuring that bolts are appropriately tightened for large-scale civil infrastructures are crucial. This study investigates …

Numerical Modeling And Conjugate Heat Transfer Analysis Of Single U-Tube Vertical Borehole Heat Exchangers, Talha Khan

FIU Electronic Theses and Dissertations

The primary purpose of this thesis was to develop a design for improving the efficiency of the vertical type single u-tube borehole heat exchanger. A thorough literature review of the various existing analytical and numerical models of the borehole heat exchanger (BHEs) was performed and numerical modeling of the BHE was conducted to solve the conjugate heat transfer problem in the BHE in 3D using ANSYS Fluent 2019 R1. A comparison between the results obtained using various mesh sizes, types, different turbulence models showed the independence of the parameters on the numerical simulation results.

From the numerical simulation, it was …

Prefilling Mylar Capacitor Edge Margins To Improve Capacitor Reliability And Size, Chase Kayser

Mechanical Engineering ETDs

Typical high-voltage, wound film-foil capacitors have large edge margins filled with air to prevent breakdown between foil electrodes. This arrangement is inefficient for energy density and leaves a volume where particulates may settle in an uncontrolled atmosphere. The reliability and size of high-voltage, wound film-foil capacitors could be improved by adding a material with higher breakdown strength into the edge margins. This will not only improve reliability and size but also act as a barrier to prevent foreign object debris (FOD), volatile organic compounds (VOCs), and water from damaging the capacitor’s performance. This paper will discuss the process of determining …

Centrifugal Microfluidic Platform For Solid-Phase-Extraction (Spe) And Fluorescence Detection Applications, Yong Zhang

LSU Doctoral Dissertations

Solid phase extraction (SPE) is a widely used method to separate and concentrate the target molecules in liquid mixture. Traditional SPE has to be conducted in the laboratory with professional equipment and skilled operators. The microfluidic and 3D printing technology have opened up the opportunity in developing miniaturized automatic instruments. The main contribution of this research is to integrate the SPE process on a novel centrifugal platform. Various valves are applied on the platform to help control the aqueous sample and reagents in the cartridge.

First, a centrifugal microfluidic platform was built for automatically detecting trace oil pollution in water. …

A New Method Of Statcom Controlling For Harmonic Mitigation And Power Factor Correction, Doha Jdeed

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

This paper presents a control algorithm of 3ph STATic synchronous COMpensator (STATCOM). The algorithm depends on the accurate reference currents extraction from only the nonlinear load current spec-trum in frequency domain using Fast Fourier Transfer (FFT). Then the determined harmonics and reactive components of load current are added together to form the compensating reference signals, the PI controllers then generate signals which control the Pulse Width Modulation (PWM) method. The simulation of the study is carried out under MATLAB/Simulink environment to show the usefulness of this control algorithm with nonlin-ear dynamic loads. It determines exactly the phase shift between the …

The Energy Efficiency Of Maritime Autonomous Surface Ship (Mass), Dang Cuong Nguyen

World Maritime University Dissertations

No abstract provided.

The Application Of Renewable Energy Supply In A Port Container Terminal : Bandar Abbas Port Container Terminal Case Study, Zhila Gordani

World Maritime University Dissertations

No abstract provided.