Mechanical Engineering Commons^™

Ultra-Broadband And Polarization-Insensitive Metasurface Absorber With Behavior Prediction Using Machine Learning, Shobhit K. Patel, Juveriya Parmar, Vijay Katkar, Fahad Ahmed Al-Zahrani, Kawsar Ahmed

Department of Mechanical and Materials Engineering: Faculty Publications

The solar spectrum energy absorption is very important for designing any solar absorber. The need for absorbing visible, infrared, and ultraviolet regions is increasing as most of the absorbers absorb visible regions. We propose a metasurface solar absorber based on Ge₂Sb₂Te₅ (GST) substrate which increases the absorption in visible, infrared and ultraviolet regions. GST is a phase-changing material having two different phases amorphous (aGST) and crystalline (cGST). The absorber is also analyzed using machine learning algorithm to predict the absorption values for different wavelengths. The solar absorber is showing an ultra-broadband response covering a 0.2–1.5 …

Rapid On Site Repair Of Wind Turbines By Cold Spray, Behrad Koohbor, Francis M. Haas, Joseph F. Stanzione Iii

Henry M. Rowan College of Engineering Departmental Research

No abstract provided.

Non-Contact Condition Monitoring Of Wind Turbines Using Laser Vibrometers, Chen Shen, Ratneshwar Jha, Nand K. Singh

Henry M. Rowan College of Engineering Departmental Research

No abstract provided.

Design And Characterization Of A Novel Reverberation Chamber For Measuring Sound Transmission Loss In 3d Printed Multimaterials, Trigun Dinesh Maroo

Theses and Dissertations

Acoustic localization of robots in indoor environments suffer from inevitable reverberation, for which, the use of unidirectional microphones as sensory receptors is preferred. While unidirectional microphones remain prohibitively expensive for ubiquitous usage, externally applying a custom structure around an inexpensive omnidirectional microphone can also grant it desired directionality. The structure can be fabricated via single or multimaterial 3D printing, and its effectiveness can be determined via its Sound Transmission Loss (STL). As an alternative to increasing thickness of a 3D printed single material structure, this research proposes the use of 3D printed multimaterial structures to achieve increased STL. The following …

Quantifying Functional Performance Of Manual Force Perception And Dynamic Force Control, Benjamin Rigsby

USF Tampa Graduate Theses and Dissertations

This dissertation furthers our understanding of how we (humans) sense and interact withforces, humans, and robots in three distinct cases, which affect robotics and rehabilitation. Chapter 2 examines physical therapists’ (PTs’) consistency when applying assistance forces during rehabilitation. Chapter 3 explores how control performance of an unstable system is affected by the system’s degrees of freedom (DoFs). Chapter 4 investigates the effects of the task speed and direction of perturbing forces on a dynamic task where position is controlled through self-generated forces.

Chapter 2 quantifies the consistency of forces that PTs apply during therapy by using a robotic device. The …

Microstructural Characteristics And Mechanical Properties Of Additively Manufactured Cu–10sn Alloys By Laser Powder Bed Fusion, Abhishek Mehta, Le Zhou, Holden Hyer, Thinh Huynh, Binghao Lu, Erica J. Drobner, Sun Hong Park, Yongho Sohn

Mechanical Engineering Faculty Research and Publications

Cu – 10 wt% Sn (Cu–10Sn) alloy specimens were additively manufactured by varying the laser powder bed fusion (LBPF) processing parameters, e.g., laser power (200–350 W) and laser scan speed (100–1400 mm/s) at a fixed hatch spacing (0.12 mm) and slice thickness (0.03 mm), to examine their effects on the density, melt pool structure, and microstructure. Microstructural characteristics of the most dense sample were examined using electron microscopy (SEM, TEM) and X-ray Diffraction. The grains in the top-most melt pool layer showed a fan-like structure, whereas all other areas showed small columnar structure aligned nearly parallel to the build direction …

Achieving Optimal Value Of Solar: A Municipal Utility Rate Analysis, Ben Saarloos, Jason C. Quinn

Faculty Work Comprehensive List

Wind and solar renewable energy in the United States is projected to triple by 2050 to nearly 30% of total electric energy generation. The upper Midwest region (Iowa, Minnesota, and North and South Dakota in particular) is considered wind energy country and not historically known for solar energy development. In this work, Value of Solar (VOS) is developed as a photovoltaic (PV) optimization measure and analysis tool using a northwest Iowa municipality as a representative case study. By applying a top-down load duration curve system analysis, VOS is used to optimize PV orientation and compare electric rate structures for increasing …

Autonomous Design Of New Chemical Reactions Using A Variational Autoencoder, Terence Musho, Robert Tempke

Faculty & Staff Scholarship

Artificial intelligence based chemistry models are a promising method of exploring chemical reaction design spaces. However, training datasets based on experimental synthesis are typically reported only for the optimal synthesis reactions. This leads to an inherited bias in the model predictions. Therefore, robust datasets that span the entirety of the solution space are necessary to remove inherited bias and permit complete training of the space. In this study, an artificial intelligence model based on a Variational AutoEncoder (VAE) has been developed and investigated to synthetically generate continuous datasets. The approach involves sampling the latent space to generate new chemical reactions. …

Standards-Compatible Smoke Points For Mono- And Un- Substituted Cycloalkane Fuel Components, Adekunle Vincent Adeniyi

Theses and Dissertations

Emissions from the aviation industry have increased significantly over the decades and may continue to pose an environmental threat. Accordingly, efforts are being made to replace conventional aviation fuels with more sustainable alternatives that can both reduce net CO2 emissions as well as reduce other pollutants (i.e., particulates). Conventional jet fuels include aromatic species, which have high sooting tendency. Therefore, to reduce particulate emissions, the fuel aromatics content must be reduced. Cycloalkanes have potential for replacing aromatics content in jet fuel but, compared to other broad classes of chemical species that make up conventional and alternative jet fuel, there is …

Evaluation Of Microstructural And Mechanical Behavior Of Ahss Cp780 Steel Welded By Gmaw-Pulsed And Gmaw-Pulsed-Brazing Processes, Alan Jadir Romero-Orozco, Jaime Taha-Tijerina, Rene De Luna-Alanis, Victor Hugo Lopez-Morelos, Maria Del Carmen Ramirez, Melchor Salazar-Martinez, Francisco Fernando Curiel-Lopez

Manufacturing & Industrial Engineering Faculty Publications

Joints of complex phase 780 (CP-780) advanced high strength steel (AHSS) were carried out by using an ER-CuAl-A2 filler metal for the gas metal arc welding pulsed brazing (GMAW-P- brazing) process and the ER-80S-D2 for the GMAW-P process employing two levels of heat input. The phases in the weld bead and HAZ were analyzed, and the evaporation of zinc by means of scanning electron microscopy (SEM) was also monitored. The mechanical properties of the welded joints were evaluated by tension, microhardness and vertical impact tests. It was found that there was greater surface Zn evaporation in the joints welded with …

Elimination Of Extraordinarily High Cracking Susceptibility Of Aluminum Alloy Fabricated By Laser Powder Bed Fusion, Holden Hyer, Le Zhou, Sharon Park, Thinh Huynh, Abhishek Mehta, Saket Thapliyal, Rajiv S. Mishra, Yongho Sohn

Mechanical Engineering Faculty Research and Publications

Using the calculation of phase diagrams approach and Scheil solidification modeling, the Al-2.5Mg-1.0Ni-0.4Sc-0.1Zr alloy was designed, intentionally with an extraordinarily high cracking susceptibility, making it prime for solidification cracking during laser powder bed fusion. This study demonstrates the ability to mitigate even the most extreme solidification cracking tendencies in aluminum alloys with only minor alloying additions of Sc and Zr, 0.5 wt.% max. Furthermore, by employing a simple direct ageing heat treatment, good tensile mechanical properties were observed with a yield strength of 308 MPa, an ultimate tensile strength of 390 MPa, and a total elongation of 11%.

A Non-Iteration Solution For Solving The Backward-In-Time Two-Dimensional Burgers’ Equation With A Large Reynolds Number, Yen-Shen Chang, Yung-Wei Chen, Chein-Shan Liu, Jiang-Ren Chang

Journal of Marine Science and Technology–Taiwan

This article proposes a noniteration solution based on the Lie-group shooting method (LGSM) to solve the backward-in-time two-dimensional Burgers’ equation with a large Reynolds number. The backward problem is famous for seriously ill-posed cases because the solution is generally unstable and highly dependent on the input data. Small perturbations in the input data, such as random errors inherent to the measurements in the analysis, can cause large oscillations in the solution. To handle a large Reynolds number under long time spans, it is very difficult to integrate towards the time direction. To avoid time integration and numerical iteration, the noniteration …

Polyketides And Terpenes In Marine Microalgae: Ecological Roles And Mechanisms Of Biosynthesis, Yunxuan Xie, Mohammad Elsheikh

Journal of Marine Science and Technology–Taiwan

Marine microalgae comprise a large number of polyketides and terpenes identified to date with highly diverse molecular scaffolds and the biological activities (Kalaitzis et al., 2010). These compounds play significant roles in marine food web and nutraceutical supplementation in marine animals. Compounds of this class are often synthesized by gene clusters with dedicated domains responsible for carbon chain extension and modification. The unique molecular structure of these compounds encourages people to investigate their biosynthetic mechanisms in-depth. In this review, we summarize relevant articles to unravel the shared mechanisms of these compounds to further understand the variety of domain organizations and …

Unbaited Light-Emitting Diode Traps Performance For Catching Orange Mud Crabs, Muhamad Naimullah, Kuo-Wei Lan, Mhd Ikhwanuddin, Adnan Amin-Safwan, Wei-Yu Lee

Journal of Marine Science and Technology–Taiwan

Mud crabs (Scylla spp.) are a vital fishery resource and targeted for a valuable source of income for coastal communities throughout the Indo-Pacific region. Baited traps are a considerable expense in crustacean fishing. Hence, the present study was performed to investigate the catchability of Scylla olivacea in response to light-emitting diodes (LEDs) in captivity and field conditions. We used a new experimental setup in the captivity condition that revealed most S. olivacea were attracted to green, blue, and white LED lights and no attractive effect by red LED lights similar to the controls. Field studies have shown that the catch …

Catch And Effort Standardization For Taiwanese Swordtip Squid Uroteuthis Edulis Fisheries In The Southern East China Sea, Ke-Yang Chang, Yu-Jie Hsu, Tzu-Yun Ching, Cheng-Hsin Liao, Chih-Shin Chen

Journal of Marine Science and Technology–Taiwan

The swordtip squid Uroteuthis edulis is a neritic squid species that is widely distributed within the coastal waters of subtropical and tropical Indo-western Pacific regions. This squid is a commercially important species throughout its distribution range and plays a critical role in marine ecosystems. Stock assessments of the squid in the East China Sea (ECS) are scarce, although it is crucial information for the sustainability of the squid and relevant fisheries. The squid was harvested by various fisheries in the southern ECS, which could restrict methods for catch-effort standardization. In this study, catch-effort data of Taiwanese swordtip squid fisheries in …

Uniform Torsion Analysis Of Composite Shafts Using Point Collocation Method Based On Pascal Polynomials, Chih-Wen Chang, Jyh-Hong Wu, Ying-Ru Lin, Yu-Feng Lin, Nan-Nong Huang

Journal of Marine Science and Technology–Taiwan

Torsion bars are important elements in the marine structure applications. The usage of the composite torsion bars has increased recently because it takes advantage of the different material property of each constituent. The current research focuses mainly on the uniform warping analysis of composite torsion shafts by using the point collocation method (PCM). The PCM is based on Pascal's triangle polynomial expansion and coupled with subdomain technique that is indispensable for the analysis of composite bars. In addition to satisfying the field equation (Laplace equation for warping function) and traction-free boundary condition for each component, the continuity conditions in both …

Local Reinforcement Design And Safety Factor Evaluation Of Elliptical Hatch Of Pressure Hull, Guang-Min Luo, Jun-Wei Chen

Journal of Marine Science and Technology–Taiwan

A pressure hull is the primary pressure-resistant structure of a submarine. To safeguard the compressive strength of such a hull, local structural reinforcement is required for various hatches on the hull. Hatches are commonly reinforced through increasing the thickness of the hull regions around them; alternatively, hatch nozzle walls are connected with stiffened frames to maintain the continuity of reinforced structures. This study focused on a pressure hull with an elliptical hatch. A PD-5500 cylindrical pressure hull was used to design a cylindrical pressure hull structure, and a model of hatch nozzle reinforcement was designed using the Boiler and Pressure …

Effects Of Dietary Lipid, L-Carnitine And L-Lysine Supplementation On The Growth Performance And Body Composition Of Epinephelus Lanceolatus Larvae, Jen-Hong Chu, Yu-Cong Hong, Angela Chien, Shyn-Shin Sheen

Journal of Marine Science and Technology–Taiwan

The effects of different combinations of dietary lipid, L-carnitine and L-lysine on the growth performance and fatty acid profiles of larval grouper Epinephalus lanceolatus were evaluated. Eight treatment diets were formulated based on a 2x2x2 factorial design, namely 5 and 14% dietary oil mixture (3:1 fish oil/soybean oil), 0 and 0.5% L-carnitine and 0 and 2.83% L-lysine. Each diet was randomly assigned to triplicate groups of ten 0.08g E. lanceolatus larvae for 42 days. The grouper larvae fed with diets containing 14% lipid had significantly higher weight gain percentages than those fed with diets containing 5% lipid. The weight gain …

A Deep Learning-Based Approach To Extraction Of Filler Morphology In Sem Images With The Application Of Automated Quality Inspection, Md. Fashiar Rahman, Tzu-Liang Bill Tseng, Jianguo Wu, Yuxin Wen, Yirong Lin

Engineering Faculty Articles and Research

Automatic extraction of filler morphology (size, orientation, and spatial distribution) in Scanning Electron Microscopic (SEM) images is essential in many applications such as automatic quality inspection in composite manufacturing. Extraction of filler morphology greatly depends on accurate segmentation of fillers (fibers and particles), which is a challenging task due to the overlap of fibers and particles and their obscure presence in SEM images. Convolution Neural Networks (CNNs) have been shown to be very effective at object recognition in digital images. This paper proposes an automatic filler detection system in SEM images, utilizing a Mask Region-based CNN architecture. The proposed system …

Estimating The As-Placed Grout Volume Of Auger Cast Piles, Tristen Mee

USF Tampa Graduate Theses and Dissertations

Augered Cast-in-Place (ACIP) piles are a geotechnical foundation element increasingly used to support large publicly funded structures as an alternative to drilled shafts or driven piles. ACIP piles are constructed by drilling an excavation to the full length of the designed pile with a continuous flight auger. Grout (cement, sand, and water mixture) is then pumped through the hollow auger stem to begin grouting the excavation. After establishing an initial head pressure, the auger is slowly extracted while the remainder of the pile is grouted. Once the auger is completely removed, the steel reinforcement cage is lowered into the grouted …

Deep Learning Approach For Chemistry And Processing History Prediction From Materials Microstructure, Amir Abbas Kazemzadeh Farizhandi, Omar Betancourt, Mahmood Mamivand

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Finding the chemical composition and processing history from a microstructure morphology for heterogeneous materials is desired in many applications. While the simulation methods based on physical concepts such as the phase-field method can predict the spatio-temporal evolution of the materials’ microstructure, they are not efficient techniques for predicting processing and chemistry if a specific morphology is desired. In this study, we propose a framework based on a deep learning approach that enables us to predict the chemistry and processing history just by reading the morphological distribution of one element. As a case study, we used a dataset from spinodal decomposition …

Intermediate Temperature Solid Oxide Cell With A Barrier Layer Free Oxygen Electrode And Phase Inversion Derived Hydrogen Electrode, Yongliang Zhang, Nansheng Xu, Qiming Tang, Kevin Huang

Faculty Publications

High-temperature solid oxide cells (SOCs) have fundamental advantages in efficiency and product rate over their low-temperature counterparts. However, the commercial development of SOCs is hindered by cost and reliability. To solve the issues, lowering the operating temperature of SOCs is deemed the best solution. Here we report on our effort toward intermediate temperature (IT) SOCs by developing a barrier layer free high-performance oxygen electrode and open structured hydrogen electrode. The results show that the new oxygen electrode provides reasonably good oxygen electrocatalytic activity at IT range for oxygen reduction and evolution reactions and the open structured hydrogen electrode provides low …

Innovations In Engineering Education For Fast-Paced Virtual Summer Courses, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications

In this study, the recently developed CIRE (Communication, Initiation, Reduction, and Extension) pedagogical model was modified to generate an effective framework for a virtual, fast-paced summer engineering course in a private university in Texas. Transitioning to fully online courses in the wake of COVID-19 required rectifying traditional instructional methods to overcome challenges such as the lack of academic resources and established campus practices, while simultaneously ensuring the academic development of students. Thus, a pedagogical framework known as the CIRE model was recently designed and implemented in a Rigid Body Dynamics course, which according to the study, generated favorable results. To …

An Accurate And Computationally Efficient Method For Battery Capacity Fade Modeling, D. M. Ajiboye, Jonathan W. Kimball, R.(Robert) G. Landers, John (T.) Park

Electrical and Computer Engineering Faculty Research & Creative Works

The Industry Demand for Accurate and Fast Algorithms that Model Vital Battery Parameters, E.g., State-Of-Health, State-Of-Charge, Pulse-Power Capability, is Substantial. One of the Most Critical Models is Battery Capacity Fade. the Key Challenge with Physics-Based Battery Capacity Fade Modeling is the High Numerical Cost in Solving Complex Models. in This Study, an Efficient and Fast Model is Presented to Capture Capacity Fade in Lithium-Ion Batteries. Here, the High-Order Chebyshev Spectral Method is Employed to Address the Associated Complexity with Physics-Based Capacity Fade Models. its Many Advantages, Such as Low Computational Memory, High Accuracy, Exponential Convergence, and Ease of Implementation, Allow …

The Effect Of Store-To-Store Energy Transfers On The Global Dynamics Of Aircraft, Guilherme Mainieri Eymael

Honors Program: Senior Projects (Public)

This study analyzes the energy transfer mechanisms when nonlinear devices (stores) are attached to a linear model airplane. For that, a reduced-order model (ROM) was derived to simulate the first two flexible modes of vibration of the primary structure (aircraft) with one store in each wing. Each store can either be locked or unlocked. When locked, it only contributes as mass-effect, and when unlocked, it adds nonlinearity to the system. Simulations were then performed with either both stores locked, one store unlocked, or both stores unlocked. It was found that the attachment of nonlinear stores in the ROM changes the …

Evaluation Of Hydrodynamic Effects Of Waterway Restoration On An Estuarine Ecosystem, Megan Kramer

USF Tampa Graduate Theses and Dissertations

Estuaries are hydrodynamically complex for they are influenced by tidal forces, freshwater flows, salinity variations, and often intricate coastal land morphology. Furthermore, many estuaries are subject to constant anthropogenic stresses due to dense coastal populations, which are expected to be exacerbated by changing climate trends. The 1,800 home residential Manchester Waterway (MW) community located in Charlotte Harbor (along the Gulf of Mexico in Southwest Florida), is interested in improving boat access by restoring a previous connection between the local waterway and the harbor, separated by a barrier peninsula. The proposed connections aim to reduce boat traffic and travel time through …

Quantification Of Reynolds Shear Stress Wave-Phase Dependence In Fixed-Bottom Offshore Wind Turbine Via Quadrant Analysis, Cerrina Mouchref

University Honors Theses

As the need for a reliable renewable energy supply is increasing, many have looked to offshore wind because they hold more potential for power production than onshore wind. Interests in expanding offshore wind energy has brought along many challenges when it comes to understanding the complex dynamics experienced offshore, including the relationship between the wind-turbine generated wakes and ocean waves. This experimental study characterizes the relationship between Reynolds shear stress and the phase of surface waves above the air-sea interface in the wind-turbine wake region. The experimental setup combines a wave tank, wind tunnel, and a fixed-bottom wind turbine. Particle …

Development Of Controller Area Network Bus Programming For Quarter-Scale Tractor Pulling Sled, Brittani Wacker

Honors Program: Senior Projects (Public)

Usage of Controller Area Network (CAN) technology has allowed for advancements in many industries, including agriculture. Most importantly, its application is useful for refining data acquisition methods. With support from the Quarter-scale Tractor Design Team at UNL, this project united a CAN bus with the team’s current tractor pulling sled. The objectives were to install new instrumentation needed for the CAN bus and to program the updated system utilizing CAN data. The program needed to give the pulling sled functionality and the ability to read and log important pulling data. These goals were all accomplished by implementing new sensors, coding …

Polarization-Sensitive Optical Responses From Natural Layered Hydrated Sodium Sulfosalt Gerstleyite, Ravi P. N. Tripathi, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Multi-element layered materials have gained substantial attention in the context of achieving the customized light-matter interactions at subwavelength scale via stoichiometric engineering, which is crucial for the realization of miniaturized polarization-sensitive optoelectronic and nanophotonic devices. Herein, naturally occurring hydrated sodium sulfosalt gerstleyite is introduced as one new multi-element van der Waals (vdW) layered material. The mechanically exfoliated thin gerstleyite flakes are demonstrated to exhibit polarization-sensitive anisotropic linear and nonlinear optical responses including angle-resolved Raman scattering, anomalous wavelength-dependent linear dichroism transition, birefringence effect, and polarization-dependent third-harmonic generation (THG). Furthermore, the third-order nonlinear susceptibility of gerstleyite crystal is estimated by the probed …

The Optimal Relationship Between Actuator Stiffness And Actuation Timing For A Passive Ankle Exoskeleton: An Opensim Simulation, Cody Anderson, Hafizur Rahman, Sara Myers

UNO Student Research and Creative Activity Fair

Introduction

The passive ankle exoskeleton developed by Collins et al. (2015) reduced the metabolic cost of walking with an actuation-timing of ~16% of stance [1]; however, other actuation timings have not been extensively investigated. Therefore, the purpose of this study was to determine the optimal relationship between actuator-stiffness and actuation-timing for a passive ankle exoskeleton by using musculoskeletal modeling.

Methods

Kinematics and ground reaction forces were recorded while a healthy-young male walked on overground force-plates, and these data were exported to a musculoskeletal modeling software (OpenSim) for simulation. A passive ankle exoskeleton model was designed and integrated with a default …