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Generation Of Nondiffracting Vector Beams With Ring-Shaped Plasmonic Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao 2019 Missouri University of Science and Technology

Generation Of Nondiffracting Vector Beams With Ring-Shaped Plasmonic Metasurfaces, Yuchao Zhang, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Nondiffracting Bessel, Mathieu, and Weber vector beams are generated by using ring-shaped plasmonic geometric metasurfaces. The nondiffracting vector beam is produced by the superposition of two off-axis right-handed and left-handed circularly polarized nondiffracting scalar beams described by the Whittaker integral, which are simultaneously generated by a single metasurface with the ring-shaped phase profile. The polarization states of the generated nondiffracting vector beams are analyzed by the Stokes parameters and the orbital angular momentum states are measured by the beam interference. In addition, the selfhealing properties of nondiffracting vector beams are further demonstrated, showing that not only the beam profiles but ...


Tomato Puree Convective Heat Transfer Simulation Using Boussinesq Approximation, Matteo Fabbri 2019 New Jersey Institute of Technology

Tomato Puree Convective Heat Transfer Simulation Using Boussinesq Approximation, Matteo Fabbri

Theses

With the advance of new technologies, the food industries are requiring systems that allow to produce the desired products with faster rates at cheaper costs. In this case, the study was initiated with the purpose to better understand what happens inside a package containing tomato puree when this is heated above 343 K in a tunnel pasteurizer. If the fluid must reach the thermal and microbiological condition of “pasteurization”, the system must guarantee that the temperature (around 343° Kelvin) is kept for a certain time allowing to pasteurize even the cooler package’s fluid-particle. The faster the system can heat ...


Mechanics Of Binder-Particle Interactions In Composite Battery Electrodes, Richard Johnson 2019 New Jersey Institute of Technology

Mechanics Of Binder-Particle Interactions In Composite Battery Electrodes, Richard Johnson

Theses

A study into the particle level mechanics of polymer binder and active material used in composite lithium-ion batteries (LIB) has been conducted. Silicon is highly sought after material that can be used as an active material in a composite anode. Its high theoretical capacity can result in batteries that can store more energy than current LIBs, but high volume expansion of Si during charge/discharge cycles leads to rapid capacity fade and poor cyclic life. Understanding the stress that is generated in the binder and the active material due to the volume expansion has not been fully understood. In this ...


Binary 2d Morphologies Of Polymer Phase Separation: Dataset And Python Toolbox, Viraj Shah, Ameya Joshi, Balaji Sesha Sarath Pokuri, Sambuddha Ghosal, Soumik Sarkar, Baskar Ganapathysubramanian, Chinmay Hegde 2019 Iowa State University

Binary 2d Morphologies Of Polymer Phase Separation: Dataset And Python Toolbox, Viraj Shah, Ameya Joshi, Balaji Sesha Sarath Pokuri, Sambuddha Ghosal, Soumik Sarkar, Baskar Ganapathysubramanian, Chinmay Hegde

Baskar Ganapathysubramanian

Study of the intricate connection between the design of material distributions (also called morphology or microstructure) and the final properties of the material system has been an attractive research theme for material science community. Such analysis provides ability to synthesize the microstructures exhibiting desired properties. This theme encompasses several material systems including porous materials [26], steels and welds [2], composites [14], powder metallurgy [28], 3D printing [22], energy storage devices as batteries [10], and energy converting devices like bulk hetero-junction solar cells [20]. Microstructure-sensitive design has been used to tailor a wide variety of properties including strengths, heat and mass ...


Investigation Of Nondestructive Testing Methods For Friction Stir Welding, Hossein Taheri, Margaret Kilpatrick, Matthew Norvalls, Warren Harper, Lucas Koester, Timothy Bigelow, Leonard J. Bond 2019 Georgia Southern University

Investigation Of Nondestructive Testing Methods For Friction Stir Welding, Hossein Taheri, Margaret Kilpatrick, Matthew Norvalls, Warren Harper, Lucas Koester, Timothy Bigelow, Leonard J. Bond

Electrical and Computer Engineering Publications

Friction stir welding is a method of materials processing that enables the joining of similar and dissimilar materials. The process, as originally designed by The Welding Institute (TWI), provides a unique approach to manufacturing—where materials can be joined in many designs and still retain mechanical properties that are similar to, or greater than, other forms of welding. This process is not free of defects that can alter, limit, and occasionally render the resulting weld unusable. Most common amongst these defects are kissing bonds, wormholes and cracks that are often hidden from visual inspection. To identify these defects, various nondestructive ...


Swarm-Based Techniques For Adaptive Navigation Primitives, Nathan Metzger 2019 Santa Clara University

Swarm-Based Techniques For Adaptive Navigation Primitives, Nathan Metzger

Mechanical Engineering Master's Theses

Adaptive Navigation (AN) has, in the past, been successfully accomplished by using mobile multi-robot systems (MMS) in highly structured formations known as clusters. Such multi-robot adaptive navigation (MAN) allows for real-time reaction to sensor readings and navigation to a goal location not known a priori. This thesis successfully reproduces MAN cluster techniques via swarm control techniques, a less computationally expensive but less formalized control technique for MMS, which achieves robot control through a combination of primitive robot behaviors. While powerful for large numbers of robots, swarm robotics often relies on “emergent” swarm behaviors resulting from robot-level behaviors, rather than top-down ...


Surface Engineering Solutions For Immersion Phase Change Cooling Of Electronics, Brendon M. Doran 2019 Louisiana Tech University

Surface Engineering Solutions For Immersion Phase Change Cooling Of Electronics, Brendon M. Doran

Master's Theses

Micro- and nano-scale surface modifications have been a subject of great interest for enhancing the pool boiling heat transfer performance of immersion cooling systems due to their ability to augment surface area, improve wickability, and increase nucleation site density. However, many of the surface modification technologies that have been previously demonstrated show a lack of evidence concerning scalability for use at an industrial level. In this work, the pool boiling heat transfer performance of nanoporous anodic aluminum oxide (AAO) films, copper oxide (CuO) nanostructure coatings, and 1D roll-molded microfin arrays has been studied. Each of these technologies possess scalability in ...


Modeling The Effect Of A Compartment Fire On Spaces Adjacent To A Bulkhead With And Without Attachments, Carl E. Hendrickson II 2019 University of New Orleans

Modeling The Effect Of A Compartment Fire On Spaces Adjacent To A Bulkhead With And Without Attachments, Carl E. Hendrickson Ii

University of New Orleans Theses and Dissertations

Structural fire protection is an integral component of shipboard fire safety. There are national and international regulations that delineate requirements for the insulation placed throughout ships. The attachments that penetrate the insulation for hanging wires and pipes can disrupt the integrity of the division, and cause a failure to adhere to the regulations. This problem will be analyzed by using a simplified lumped capacitance model and ANSYS FLUENT CFD. A standard time-temperature fire curve is applied to the fire side of the enclosure. The thermal conductivity of the insulation and steel are made to be temperature dependent. The density of ...


Mechanical Properties And Applications Of Recycled Polycarbonate Particle Material Extrusion-Based Additive Manufacturing, Matthew J. Reich, Aubrey Woern, Nagendra Gautam Tanikella, Joshua M. Pearce 2019 Michigan Tech

Mechanical Properties And Applications Of Recycled Polycarbonate Particle Material Extrusion-Based Additive Manufacturing, Matthew J. Reich, Aubrey Woern, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications

Past work has shown that particle material extrusion (fused particle fabrication (FPF)/fused granular fabrication (FGF)) has the potential for increasing the use of recycled polymers in 3D printing. This study extends this potential to high-performance (high-mechanical-strength and heat-resistant) polymers using polycarbonate (PC). Recycled PC regrind of approximately 25 mm2 was 3D printed with an open-source Gigabot X and analyzed. A temperature and nozzle velocity matrix was used to find useful printing parameters, and a print test was used to maximize the output for a two-temperature stage extruder for PC. ASTM type 4 tensile test geometries as well as ...


Design And Control Of Fiber Encapsulation Additive Manufacturing, Matt Saari 2019 Southern Methodist University

Design And Control Of Fiber Encapsulation Additive Manufacturing, Matt Saari

Mechanical Engineering Research Theses and Dissertations

This work presents the design, development, and analysis of the Fiber Encapsulation Additive Manufacturing (FEAM) system developed at the Laboratory for Additive Manufacturing Robotics \& Automation at the Lyle School of Engineering at Southern Methodist University. The innovation introduced by FEAM is the ability to insert a continuous fiber of different material into the flowing extrudate. Correctly positioning the fiber feed inside the extrudate while turning the fiber in arbitrary directions is a critical aspect of the technology. This will allow for the full exploitation of the capabilities of the FEAM technology to produce robotic components that actuate and sense. Several ...


Computation Of Flow Fields Due To Single- And Twin-Jet Impingement, Xiang Zhang 2019 Washington University in St. Louis

Computation Of Flow Fields Due To Single- And Twin-Jet Impingement, Xiang Zhang

Engineering and Applied Science Theses & Dissertations

The thesis consists of two parts. The first part focuses on numerical simulations and their comparison with experimental data for single-jet impingement on ground. Angles between the axisymmetric jet and impingement surface considered are 15, 30 and 90 degree. It is shown that both the k-epsilon and Wray-Agarwal (WA) model can predict the flow fields in good agreement with the experimental results. The second part extends the first part to twin-jet normal impingement on the ground. It focuses on numerical simulation of fountains formed by the twin-jet impingement. The fountains can be normal straight upward when the two jets are ...


Modeling Mechanisms Behind Force Generation By Actin Polymerization, Seyed Fowad Motahari 2019 Washington University in St. Louis

Modeling Mechanisms Behind Force Generation By Actin Polymerization, Seyed Fowad Motahari

Arts & Sciences Electronic Theses and Dissertations

Actin polymerization is the primary mechanism for overcoming the large turgor pressure that opposes endocytosis in yeast. While generation of pushing forces by actin polymerization is fairly well understood, it is not clear how actin polymerization produces pulling forces. In order to understand this process, it is necessary to simulate polymerization of filaments having various types of interactions with the membrane. Since existing methodologies in the literature do not treat such problems correctly, we develop a thermodynamically consistent methodology for treating polymerization of filaments having arbitrary interaction potentials with the membrane. Then I perform stochastic simulations for a system of ...


Agent-Based Microgrid Architecture For Generation Following Protocols, Steven Goldsmith 2019 Michigan Technological University

Agent-Based Microgrid Architecture For Generation Following Protocols, Steven Goldsmith

Michigan Tech Patents

A system for predicting power and loads over a single, relatively short time horizon. More specifically, a system comprising a Storage Agent (S-agent) Cohort within a grid control society, wherein the system expands G and L intra-cohort protocols to allow the S-cohort to participate in power management of the grid by scheduling storage components in source or load roles as determined by the time-varying state of the power imbalance and by the risk-adjusting capacity margin relationship between the G and L cohorts.


Fracture Toughness Improvement Of ����� Ceramics By Grain Size Control And Ductile Phase Reinforcement, Kesong Wang 2019 Washington University in St. Louis

Fracture Toughness Improvement Of ����� Ceramics By Grain Size Control And Ductile Phase Reinforcement, Kesong Wang

Engineering and Applied Science Theses & Dissertations

This study used grain size control and ductile phase reinforcement to improve fracture toughness of ����� ceramics. Alpha alumina particles of 100 nm, 0.5-1 micrometers, and 10 micrometers were coated with 1-5 nm nickel by electroless nickel plating (ENP). The coated powders were consolidated at 1200℃-1500℃ by spark plasma sintering (SPS). The sintered samples were annealed at 1100 oC for 1.5 hours and 10 hours to determine the effect of post sintering annealing on hardness and fracture toughness. Density of the samples were measured by the standard Archimedes method using a 5 mL pycnometer. Hardness values were determined ...


Using Complex Orthogonal Decomposition To Extract Dispersion Relationships For Mass Chain, Nicholas A. Valente, Rickey A. Caldwell 2019 Merrimack College

Using Complex Orthogonal Decomposition To Extract Dispersion Relationships For Mass Chain, Nicholas A. Valente, Rickey A. Caldwell

Across the Bridge: The Merrimack Undergraduate Research Journal

Complex orthogonal decomposition (COD) was used to determine the extracted dispersion relationship of a traveling wave in a mass chain. When COD extracts a wavenumber it will produce M values for each wavenumber, γi, and N values for each frequency, ωi; where M is the number of masses and N is the number of time samples. In this work, least squares and a simple mean of the M-γi’s and N-ωi’s extracted values were used to determine each γi and ωi, respectively. An analytical dispersion relationship for the mass-chain is derived in addition to an approximate dispersion relationship. The ...


Thermal And Orbital Analysis Of Darkness Cubesat, Katie Dickey 2019 Olivet Nazarene University

Thermal And Orbital Analysis Of Darkness Cubesat, Katie Dickey

Honors Program Projects

Fermi National Accelerator Laboratory is sending a 3U CubeSat into LEO to search for a 3.5 keV photon corresponding to the decay of a theorized dark matter particle called the sterile neutrino. The CubeSat will encounter environmental variations while in orbit that can be computed through an orbital analysis using System’s Tool Kit. In order to minimize thermal noise readout, improve optical resolution, and increase bandwidth, the sensors must be kept below 170K while taking data. This temperature is difficult to achieve due to radiation from the Sun and the Earth’s albedo radiation. Through the thermal analysis ...


Performance Analysis Of An Exhaust Heat Recovery System Utilizing Heat Pipes, Metal Foam, And Thermoelectric Generators, Michael Resciniti 2019 Olivet Nazarene University

Performance Analysis Of An Exhaust Heat Recovery System Utilizing Heat Pipes, Metal Foam, And Thermoelectric Generators, Michael Resciniti

Honors Program Projects

Developing efficient thermoelectric generator systems to recover wasted thermal energy from automotive exhaust gasses has potential to improve engine efficiency and reduce carbon emissions. Due to their high thermal transfer efficiency, heat pipes have been used to assist thermoelectric generator systems in these applications. To aid in additional heat transfer, metal fins are often used with heat pipes to take advantage of extended-surface heat transfer. This paper proposes a thermoelectric generator system that employs metal foam as an extended-surface heat transfer aid used in conjunction with heat pipes. Three test conditions were simulated to evaluate the system performance in terms ...


Repurposing Plastic Waste In El Cercado, Joseph Dooling, Kirby Townsend, Brendan Smith 2019 Loyola Marymount University

Repurposing Plastic Waste In El Cercado, Joseph Dooling, Kirby Townsend, Brendan Smith

Honors Thesis

This project aims to assist the community of El Cercado in the Dominican Republic in turning their plastic waste into useful products. The design team developed a first iteration shredder, injector, and aluminum mold which future design teams could further iterate in order to make products out of waste plastic. Different products were researched to ensure that they can be sold or used in the community. The goal of producing these items is to stimulate economic activity in the community by creating economic opportunity. The design shall also be sustainable in three ways. It shall reuse plastic waste while also ...


Investigating Grip Range Of Motion And Force Exerted By Individuals With And Without Hand Arthritis During Functional Tasks And While Swinging A Golf Club, Sara Frances Holland 2019 The University of Western Ontario

Investigating Grip Range Of Motion And Force Exerted By Individuals With And Without Hand Arthritis During Functional Tasks And While Swinging A Golf Club, Sara Frances Holland

Electronic Thesis and Dissertation Repository

Hand arthritis is the leading cause of disability in individuals over the age of 50; resulting in dysfunction and pain, making activities of daily living and recreational activities such as golf difficult. Few studies have been conducted on the biomechanical response of individuals with hand arthritis when performing functional activities. This research quantified hand grip movements and strength differences seen in individuals with hand arthritis. Using a video-based motion capture system (Dartfish), a grip limitation of 17.2% (maximum flexion), and 12.7% (maximum extension) was discovered. A wireless finger force measurement system (FingerTPS), was used to show that larger ...


High Resolution Validation Of Next Generation Turbulent Flow Models Using Neutron Beams, Laser Fluorescence, And Cryogenic Helium, Landen G Mcdonald 2019 University of Tennessee, Knoxville

High Resolution Validation Of Next Generation Turbulent Flow Models Using Neutron Beams, Laser Fluorescence, And Cryogenic Helium, Landen G Mcdonald

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Turbulent fluid flow is an incredibly unpredictable subject that continues to confound scientists and engineers. All of the empirical data that has been the basis of conventional turbulent computational fluid dynamics (CFD) models for decades only extends to roughly the equivalent turbulence created when Michael Phelps swims in a pool. The problem is that this data is then extrapolated out many orders of magnitude in order to design cruise ships, airplanes, and rockets which operate in significantly more turbulent flow regimes. This creates an incredible degree of uncertainty in the design process that demands over-engineering and increased expenditures.

The development ...


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