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Pseudo-Spectral Method To Control Three-Degree-Of-Freedom Wave Energy Converters, Ossama Abdelkhalik, Giorgio Bacelli, Shangyan Zou, Rush D. Robinett III, David G. Wilson, Ryan G. Coe 2019 Michigan Technological University

Pseudo-Spectral Method To Control Three-Degree-Of-Freedom Wave Energy Converters, Ossama Abdelkhalik, Giorgio Bacelli, Shangyan Zou, Rush D. Robinett Iii, David G. Wilson, Ryan G. Coe

Michigan Tech Patents

The invention provides optimal control of a three-degree-of-freedom wave energy converter using a pseudo-spectral control method. The three modes are the heave, pitch and surge. A dynamic model is characterized by a coupling between the pitch and surge modes, while the heave is decoupled. The heave, however, excites the pitch motion through nonlinear parametric excitation in the pitch mode. The invention can use a Fourier series as basis functions to approximate the states and the control. For the parametric excited case, a sequential quadratic programming approach can be implemented to numerically solve for the optimal control. The numerical results show ...


High-Performance Polyvinyl Chloride Gel Artificial Muscle Actuator With Graphene Oxide And Plasticizer, Taeseon Hwang, Zachary Frank, Justin Neubauer, Kwang Jin Kim 2019 University of Nevada, Las Vegas

High-Performance Polyvinyl Chloride Gel Artificial Muscle Actuator With Graphene Oxide And Plasticizer, Taeseon Hwang, Zachary Frank, Justin Neubauer, Kwang Jin Kim

Mechanical Engineering Faculty Publications

A transparent and electroactive plasticized polyvinyl chloride (PVC) gel was investigated to use as a soft actuator for artificial muscle applications. PVC gels were prepared with varying plasticizer (dibutyl adipate, DBA) content. The prepared PVC gels were characterized using Fourier-transform infrared spectroscopy, thermogravimetric analysis, and dynamic mechanical analysis. The DBA content in the PVC gel was shown to have an inverse relationship with both the storage and loss modulus. The electromechanical performance of PVC gels was demonstrated for both single-layer and stacked multi-layer actuators. When voltage was applied to a single-layer actuator and then increased, the maximum displacement of PVC ...


Finite Element Simulation Of Bonded And Mechanically Anchored Shear Interfaces Of Externally Applied Frp Sheets To Concrete And Wood-Concrete Composites, Alaa Al-Sammari 2019 University of Massachusetts Amherst

Finite Element Simulation Of Bonded And Mechanically Anchored Shear Interfaces Of Externally Applied Frp Sheets To Concrete And Wood-Concrete Composites, Alaa Al-Sammari

Doctoral Dissertations

Composite construction is prevalent in advanced structural systems where components of different materials are combined in the same structure to improve the performance of strong and economic structural sections. Maintaining continuity between the different structural components to produce monolithic structural behavior is challenging because of differences in the mechanical properties of these materials in terms of stiffness, strength, and ductility. The different components of the composite section are typically joined using adhesives and/or mechanical anchors to produce partial or full composite action. This dissertation discusses two types of shear interfaces intended to result in structural composite behavior. The first ...


Northeastern Species In Hybrid Cross Laminated Timber, Hamid Kaboli 2019 University of Massachusetts Amherst

Northeastern Species In Hybrid Cross Laminated Timber, Hamid Kaboli

Doctoral Dissertations

Known in the building industry throughout the world, Cross Laminated Timber (CLT) is a massive timber building material with outstanding structural, fire, and seismic properties. CLT is a cost-competitive, sustainable construction material is a good candidate as a substitute material for concrete, masonry, and steel, in mid-rise and high-rise buildings. CLT is perpendicular layers of dimensional lumbers usually laminated together and forming a massive structural panel. This dissertation explores the viability of utilizing Massachusetts grown Eastern Hemlock and Eastern White Pine in CLT panels as pure or in conjunction with other high-value wood products. 59% of Massachusetts’ lands are covered ...


Investigation Of Fundamental Principles Of Rigid Body Impact Mechanics, Khalid Alluhydan 2019 Southern Methodist University

Investigation Of Fundamental Principles Of Rigid Body Impact Mechanics, Khalid Alluhydan

Mechanical Engineering Research Theses and Dissertations

In impact mechanics, the collision between two or more bodies is a common, yet a very challenging problem. Producing analytical solutions that can predict the post-collision motion of the colliding bodies require consistent modeling of the dynamics of the colliding bodies. This dissertation presents a new method for solving the two and multibody impact problems that can be used to predict the post-collision motion of the colliding bodies. Also, we solve the rigid body collision problem of planar kinematic chains with multiple contacts with external surfaces.

In the first part of this dissertation, we study planar collisions of Balls and ...


Generating Electrospray From A Ferrofluid, Lyon Bradley King 2019 Michigan Technological University

Generating Electrospray From A Ferrofluid, Lyon Bradley King

Michigan Tech Patents

An electrospray device for generating electrospray from a ferrofluid. The electrospray device includes an emitter, an extraction electrode, and a magnet. The emitter is configured to receive a ferrofluidic liquid. The extraction electrode includes an aperture and is positioned a first distance from the emitter. The magnet generates a magnetic field in a first direction toward the emitter. The magnetic field causes Rosensweig instability in the ferrofluidic liquid, and generates a ferrofluidic peak in the ferrofluidic liquid. The magnet is positioned a second distance from the emitter, and the emitter is positioned between the extraction electrode and the magnet. The ...


Effect Of The Nonlinear Material Viscosity On The Performance Of Dielectric Elastomer Transducers, Yuanping Li 2019 The University of Western Ontario

Effect Of The Nonlinear Material Viscosity On The Performance Of Dielectric Elastomer Transducers, Yuanping Li

Electronic Thesis and Dissertation Repository

As a typical type of soft electroactive materials, dielectric elastomers (DEs) are capable of producing large voltage-induced deformation, which makes them desirable materials for a variety of applications in transduction technology, including tunable oscillators, resonators, biomimetics and energy harvesters. The dynamic and energy harvesting performance of such DE-based devices is strongly affected not only by multiple failure modes such as electrical breakdown, electromechanical instability, loss-of-tension and fatigue, but also by their material viscoelasticity. Moreover, as suggested by experiments and theoretical studies, DEs possess nonlinear relaxation processes, which makes modeling of the performance of DE-based devices more challenging.

In this thesis ...


Group Iv Environmentally Benign, Inexpensive Semiconductor Nanomaterials For Solar Cells, Lisa Je 2019 Dartmouth College

Group Iv Environmentally Benign, Inexpensive Semiconductor Nanomaterials For Solar Cells, Lisa Je

ENGS 86 Independent Projects (AB Students)

Modern solar cells are composed of silicon, cadmium tellurium, and copper indium gallium diselenide. While these materials are efficient, elements such as cadmium and indium are rare and expensive. To make this renewable energy source more inexpensive and sustainable, the Liu Optics lab is substituting expensive rare earth metals for more commonly found transition state metals. Work has been done to replace the solar cell layers composed of cadmium and gallium to replace them with glass, silicon, and/or thin films. Common metals such as germanium and tin are investigated and characterized to provide a platform for solar cell components.


Me-Em Enewsbrief, June 2019, Department of Mechanical Engineering-Engineering Mechanics, Michigan Technological University 2019 Michigan Technological University

Me-Em Enewsbrief, June 2019, Department Of Mechanical Engineering-Engineering Mechanics, Michigan Technological University

Department of Mechanical Engineering-Engineering Mechanics eNewsBrief

No abstract provided.


Structural Health Monitoring Of Composite Parts: A Review, Jacob Pessin 2019 Union College - Schenectady, NY

Structural Health Monitoring Of Composite Parts: A Review, Jacob Pessin

Honors Theses

Structural health monitoring has the potential to allow composite structures to be more reliable and safer, then by using more traditional damage assessment techniques. Structural health monitoring (SHM) utilizes individual sensor units that are placed throughout the load bearing sections of a structure and gather data that is used for stress analysis and damage detection. Statistical time based algorithms are used to analyze collected data and determine both damage size and probable location from within the structure. While traditional calculations and life span analysis can be done for structures made of isotropic materials such as steel or other metals, composites ...


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 ...


Electronic Transport Behavior Of Adatom- And Nanoparticle-Decorated Graphene, Jamie Anne Elias 2019 Washington University in St. Louis

Electronic Transport Behavior Of Adatom- And Nanoparticle-Decorated Graphene, Jamie Anne Elias

Arts & Sciences Electronic Theses and Dissertations

To induce a non-negligible spin-orbit coupling in monolayer graphene, for the purposes of realizing the Kane-Mele Hamiltonian, transition metal adatoms have been deposited in dilute amounts by thermal evaporation in situ while holding the device temperature near 4K. Electronic transport studies including measurements such as gate voltage dependent conductivity and mobility, weak localization, high field magnetoresistance (Shubnikov de Haas oscillations), quantum Hall, and nonlocal voltage were performed at low temperature before and after sequential evaporations. Studies of tungsten adatoms are consistent with literature regarding other metal adatoms on graphene but were unsuccessful in producing a spin-orbit signature, at least partially ...


Defect Chemistry And Ion Intercalation During The Growth And Solid-State Transformation Of Metal Halide Nanocrystals, Bo Yin 2019 Washington University in St. Louis

Defect Chemistry And Ion Intercalation During The Growth And Solid-State Transformation Of Metal Halide Nanocrystals, Bo Yin

Engineering and Applied Science Theses & Dissertations

Abstract of the Dissertation

Defect Chemistry and Ion Intercalation During the Growth and Solid-State Transformation of Metal Halide Nanocrystals

Semiconductor metal halides as light-sensitive materials have applications in multiple areas, such as photographic film, antibacterial agents and photocatalysts. One focus of this dissertation is to achieve novel morphologies of ternary silver bromoiodide (AgBr1-xIx, 0

For the silver halide system, we demonstrate that the anion composition of AgBr1-xIx nanocrystals determines their shape through the introduction of twin defects as the nanocrystals are made more iodide-rich. AgBr1-xIx nanocrystals grow as single-phase, solid solutions with the rock salt crystal structure for anions compositions ...


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.


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 ...


Paper Watermark Imaging Using Electron And Low Energy X-Ray Radiography, Zhan Zhang, Uwe Ewert, Timothy D. Barrett, Leonard J. Bond 2019 Iowa State University

Paper Watermark Imaging Using Electron And Low Energy X-Ray Radiography, Zhan Zhang, Uwe Ewert, Timothy D. Barrett, Leonard J. Bond

Aerospace Engineering Conference Papers, Presentations and Posters

Historians and librarians are interested in watermarks and mould surface patterns in historic papers, because they represent the “fingerprints” of antique papers. However, these features are usually covered or hidden by printing, writing or other media. Different techniques have been developed to extract the watermarks in the paper while avoiding interference from media on the paper. Beta radiography provides good results, but this method cannot be widely used because of radiation safety regulations and the long exposure times required due to weak isotope sources employed. In this work, two promising methods are compared which can be used to extract digital ...


Wearable Devices For Single-Cell Sensing And Transfection, Lingqian Chang, Yu-Chieh Wang, Faheem Ershad, Ruiguo Yang, Cunjiang Yu, Yubo Fan 2019 Beihang University, Beijing

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

Mechanical & 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 ...


Liquid Metal-Elastomer Soft Composites With Independently Controllable And Highly Tunable Droplet Size And Volume Loading, Ravi Tutika, Steven Kmiec, A. B. M. Tahidul Haque, Steve W. Martin, Michael D. Bartlett 2019 Iowa State University

Liquid Metal-Elastomer Soft Composites With Independently Controllable And Highly Tunable Droplet Size And Volume Loading, Ravi Tutika, Steven Kmiec, A. B. M. Tahidul Haque, Steve W. Martin, Michael D. Bartlett

Michael Bartlett

Soft composites are critical for soft and flexible materials in energy harvesting, actuators, and multifunctional devices. One emerging approach to create multifunctional composites is through the incorporation of liquid metal (LM) droplets such as eutectic gallium indium (EGaIn) in highly deformable elastomers. The microstructure of such systems is critical to their performance, however, current materials lack control of particle size at diverse volume loadings. Here, we present a fabrication approach to create liquid metal-elastomer composites with independently controllable and highly tunable droplet size (100 nm ≦ D ≦ 80 μm) and volume loading (0 ≦ φ ≦ 80%). This is achieved through a combination ...


Equation Of State Of H2o Ice Using Melt-Recrystallization, Zachary Michael Grande 2019 University of Nevada, Las Vegas

Equation Of State Of H2o Ice Using Melt-Recrystallization, Zachary Michael Grande

UNLV Theses, Dissertations, Professional Papers, and Capstones

The recent surge in exoplanet discoveries due to advancements in astrophysical technology and analysis has brought the reliability of early equation of state measurements into question as they are the limiting factor when modeling composition of these planets. H2O content is among the most important for the search of habitable planets as well as in understanding planetary dynamics and atmosphere formation. Over the last three decades the equation of state of H2O has been investigated with various techniques but, has suffered from anisotropic strain and poor powder statistics resulting in a large discrepancy in equation of state fits. At pressures ...


Predicting The Mechanical Properties Of Nanocomposites Reinforced With 1-D, 2-D And 3-D Nanomaterials, Scott Edward Muller 2019 University of Arkansas, Fayetteville

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

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 ...


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