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Towards The Development Of A Wearable Tremor Suppression Glove, Yue Zhou
Towards The Development Of A Wearable Tremor Suppression Glove, Yue Zhou
Electronic Thesis and Dissertation Repository
Patients diagnosed with Parkinson’s disease (PD) often associate with tremor. Among other symptoms of PD, tremor is the most aggressive symptom and it is difficult to control with traditional treatments. This thesis presents the assessment of Parkinsonian hand tremor in both the time domain and the frequency domain, the performance of a tremor estimator using different tremor models, and the development of a novel mechatronic transmission system for a wearable tremor suppression device. This transmission system functions as a mechatronic splitter that allows a single power source to support multiple independent applications. Unique features of this transmission system include low …
Spectrally-Accurate Algorithm For Flows In 3-Dimensional Rough Channels, Md Nazmus Sakib
Spectrally-Accurate Algorithm For Flows In 3-Dimensional Rough Channels, Md Nazmus Sakib
Electronic Thesis and Dissertation Repository
In this work a spectrally accurate algorithm has been developed for the simulation of three-dimensional flows bounded by rough walls. The algorithm is based on the velocity-vorticity formulation and uses the concept of Immersed Boundary Conditions (IBC) for the enforcement of the boundary conditions. The flow domain is immersed inside a fixed computational domain. The geometry of the boundaries is expressed in terms of double Fourier expansions and boundary conditions enter the algorithm in the form of constraints. The spatial discretization uses Fourier expansions in the stream-wise and span-wise directions and Chebyshev expansions in the wall-normal direction. The algorithm can …
Simulation Of Magnetic Field Induced Current And Neuron Spiking For Magnetic Seizure Therapy, Abhijeet R. Wadkar
Simulation Of Magnetic Field Induced Current And Neuron Spiking For Magnetic Seizure Therapy, Abhijeet R. Wadkar
Electronic Thesis and Dissertation Repository
Magnetic seizure therapy (MST) is currently on trial to treat severe cases of depression. This thesis is concerned with getting a deeper understanding of the mechanics behind MST by employing FEA of brain. The simulations performed via COMSOL helped identify the dimensions and coil types of the MST device as well as the angular probing orientations. Largest induced current due to the externally imposed magnetic field was found in the cerebrospinal fluid which was found to act as a barrier to induce current in the gray matter. In an attempt to relate the induced current to the neuron spiking, a …
Development Of An In-Vitro Passive And Active Motion Simulator For The Investigation Of Wrist Function And Kinematics, Duncan J. Iglesias
Development Of An In-Vitro Passive And Active Motion Simulator For The Investigation Of Wrist Function And Kinematics, Duncan J. Iglesias
Electronic Thesis and Dissertation Repository
This thesis outlines the design and development of an active motion simulator for the investigation of wrist kinematics in multiple gravity loaded positions. Using optical trackers on the third metacarpal, radius, and ulna, the position of the wrist was monitored in real time without introducing material incompatibilities as present for electromagnetic tracking systems. Performance of the system was performed using a series of five cadaver upper limbs that compared the ability to produce repeatable trials using unrestrained active motion techniques over passive manipulation methods. Comparisons to achieve static positions as well as motion trials in flexion-extension and radial-ulnar deviation planes …
Flows In Vibrating Channels, Sahab Zandi
Flows In Vibrating Channels, Sahab Zandi
Electronic Thesis and Dissertation Repository
A spectral algorithm based on the immersed boundary conditions (IBC) concept has been developed for the analysis of flows in channels bounded by vibrating walls. The vibrations take the form of travelling waves of arbitrary profile. The algorithm uses a fixed computational domain with the flow domain immersed in its interior. Boundary conditions enter the algorithm in the form of constraints. The spatial discretization uses a Fourier expansion in the stream-wise direction and a Chebyshev expansion in the wall-normal direction. Use of the Galileo transformation converts the unsteady problem into a steady one. An efficient solver which takes advantage of …
Investigation Of Flow And Thermal Behaviour In A Pipe Submerged In A Hot Fluid, Ben S. Steen
Investigation Of Flow And Thermal Behaviour In A Pipe Submerged In A Hot Fluid, Ben S. Steen
Electronic Thesis and Dissertation Repository
Convection heat transfer through a pipe immersed in a stagnant fluid is used in various applications such as water heaters, chemical and food industry, etc. In this study, the effect of mixed convection on the flow and thermal structure of a fluid immersed inside a hotter, stagnant fluid was experimentally investigated. Temperature and velocity fields were obtained for a Reynolds number range of 330-6670, and a Grashof number range of 14000-95000 (0.6 < Gr/Re2 < 0.0003). It was found that the buoyancy-induced wall-normal velocity component altered the streamwise velocity structure and the temperature profiles. The mean streamwise velocity profile was skewed towards the bottom of the pipe for initially laminar flow only. A vertical temperature gradient was also observed in the internal fluid under these conditions, where the hotter fluid resided in the top region of the pipe. The Nusselt number was found to moderately follow the predictive Gnielinski correlation, with an additional dependence on the bottom wall temperature. This showed that an increase in the Grashof number tended to dampen the turbulent convective heat transfer. The influence of natural convection on the mean and turbulent velocity profiles was found to be almost negligible in the high Reynolds number range.
Electromechanical Coupling Behavior Of Dielectric Elastomer Transducers, Jianyou Zhou
Electromechanical Coupling Behavior Of Dielectric Elastomer Transducers, Jianyou Zhou
Electronic Thesis and Dissertation Repository
Dielectric elastomer transducers with large deformation, high energy output, light weight and low cost have been drawing great interest from both the research and industry communities, and shown potential for versatile applications in biomimetics, dynamics, robotics and energy harvesting. However, in addition to multiple failure modes such as electrical breakdown, electromechanical instability, loss-of-tension and fatigue, the performance of dielectric elastomer transducers are also strongly influenced by the hyperelastic and viscoelastic properties of the material. Also, the interplay among these material properties and the failure modes is rather difficult to predict. Therefore, in order to provide guidelines for the optimal design …
Development Of Glass Fiber Reinforced Poly(3-Hydroxybutyrate-Co-3-Hydroxyhexanoate), Willson Arifin
Development Of Glass Fiber Reinforced Poly(3-Hydroxybutyrate-Co-3-Hydroxyhexanoate), Willson Arifin
Electronic Thesis and Dissertation Repository
Enhancement of mechanical properties of the bacterial polyester poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) by the addition of glass fibers (GF) and thermoplastic elastomers was investigated. Glass fiber addition significantly increased Young’s modulus and strength of PHBH, but had little effect on the degree of crystallinity of PHBH. To increase ductility and/or energy absorbed in fracture, that were found to be reduced, in glass fiber reinforced PHBH composites, two types of thermoplastic elastomers, styrene-ethylene-butylene-styrene copolymer (SEBS) and maleated styrene-ethylene-butylene-styrene copolymer (SEBS-MA), were added to PHBH/GF composites. SEBS-MA was more effective than SEBS in improving ductility, fracture energy, and notched Izod impact strength of PHBH/GF …
Design And Control Of Robotic Systems For Lower Limb Stroke Rehabilitation, Aaron Yurkewich
Design And Control Of Robotic Systems For Lower Limb Stroke Rehabilitation, Aaron Yurkewich
Electronic Thesis and Dissertation Repository
Lower extremity stroke rehabilitation exhausts considerable health care resources, is labor intensive, and provides mostly qualitative metrics of patient recovery. To overcome these issues, robots can assist patients in physically manipulating their affected limb and measure the output motion. The robots that have been currently designed, however, provide assistance over a limited set of training motions, are not portable for in-home and in-clinic use, have high cost and may not provide sufficient safety or performance. This thesis proposes the idea of incorporating a mobile drive base into lower extremity rehabilitation robots to create a portable, inherently safe system that provides …
Experimental Analysis Of Parameters Influencing The Bone Burring Process, Jonathan Kusins
Experimental Analysis Of Parameters Influencing The Bone Burring Process, Jonathan Kusins
Electronic Thesis and Dissertation Repository
The experimental quantification of the bone removal characteristics associated with bone burring represents a desirable outcome mainly for the selection of optimal parameters. An experimental apparatus was developed that allowed for concurrent measurement of three outputs associated with the bone removal process (cutting force, vibration, and temperature) as a function of various burring-specific parameters. Initial process trends were established on a uniform sawbone analog through use of a fully balanced multivariate statistical analysis. A smaller set of optimal and suboptimal parameters were further validated using a porcine femur. From the parameters tested, an optimal tool configuration, to avoid high temperature …
Self-Sustaining Smouldering Combustion As A Novel Disposal Destruction Method For Waste Water Biosolids, Tarek L. Rashwan
Self-Sustaining Smouldering Combustion As A Novel Disposal Destruction Method For Waste Water Biosolids, Tarek L. Rashwan
Electronic Thesis and Dissertation Repository
Managing biosolids, the major by-product from wastewater treatment plants (WWTPs), persists as a major global challenge that often constitutes the majority of WWTP operating costs. Self-sustained smouldering is a new approach for organic waste treatment, in which the waste (i.e., the fuel) is destroyed in an energy efficient manner after mixing it with sand. Smouldering has never been applied to biosolids. Column experiments, using biosolids obtained from a WWTP, were employed to identify if - and under what conditions - smouldering could be used for treating biosolids. The parameter space in which smouldering was self-sustaining was mapped as a function …
Development Of A Wearable Mechatronic Elbow Brace For Postoperative Motion Rehabilitation, Anastasiia Kyrylova
Development Of A Wearable Mechatronic Elbow Brace For Postoperative Motion Rehabilitation, Anastasiia Kyrylova
Electronic Thesis and Dissertation Repository
This thesis describes the development of a wearable mechatronic brace for upper limb rehabilitation that can be used at any stage of motion training after surgical reconstruction of brachial plexus nerves. The results of the mechanical design and the work completed towards finding the best torque transmission system are presented herein. As part of this mechatronic system, a customized control system was designed, tested and modified. The control strategy was improved by replacing a PID controller with a cascade controller. Although the experiments have shown that the proposed device can be successfully used for muscle training, further assessment of the …
Stochastic Stability And Uncertainty Quantification Of Ring-Based Vibratory Gyroscopes, Soroush Arghavan
Stochastic Stability And Uncertainty Quantification Of Ring-Based Vibratory Gyroscopes, Soroush Arghavan
Electronic Thesis and Dissertation Repository
Effect of stochastic fluctuations in angular velocity on the stability of two DOF ring-type MEMS gyroscopes is investigated. The governing Stochastic Differential Equations are discretized using the higher-order Milstein scheme in order to numerically predict the system response assuming the fluctuations to be white noise. Simulations via Euler scheme as well as a measure of Largest Lyapunov Exponents are employed for validation purposes due to lack of similar analytical or experimental data. The stability investigation predicts that the threshold fluctuation intensity increases nonlinearly with damping ratio. Under typical gyroscope operating conditions, nominal input angular velocity magnitude and mass mismatch appear …
Studies Of Periodic And Quasiperiodic Gold Nanohole Arrays And Their Applications, Zhaoliang Yang
Studies Of Periodic And Quasiperiodic Gold Nanohole Arrays And Their Applications, Zhaoliang Yang
Electronic Thesis and Dissertation Repository
Wavelength to refractive index sensitivity and resonance wavelength position are two very important performance characteristics for nanohole array based surface plasmon resonance sensors while these characteristics are mostly researched on periodic nanohole arrays, instead of quasiperiodic nanohole arrays. This thesis deduces theoretical equations about the wavelength to refractive index sensitivity and resonance wavelength position of quasiperiodic nanohole arrays. Theoretical analysis shows that wavelength to refractive index sensitivity is not associated with geometry pattern, hole size or pitch but with the wavelength. A novel surface plasmon resonance platform is built by transferring gold films patterned with quasiperiodic nanohole arrays to the …
Response Of Endothelial Cells To Quantified Hemodynamic Shear Stress, Hamed Avari
Response Of Endothelial Cells To Quantified Hemodynamic Shear Stress, Hamed Avari
Electronic Thesis and Dissertation Repository
Cardiovascular diseases (CVDs) are the number one cause of death globally. Arterial endothelial cell (EC) dysfunction plays a key role in many of these CVDs, such as atherosclerosis. Blood flow-induced wall shear stress (WSS), among many other pathophysiological factors, is shown to significantly contribute to EC dysfunction.
The present dissertation is an in vitro investigation of quantified WSS on ECs to quantitatively analyze the EC morphometric parameters, as well as cytoskeletal remodeling.
A hemodynamic facility based on the parallel plate flow chamber (PPFC) concept. The Laser Doppler Velocimetry (LDV) method with a custom set-up was implemented to suit the needs …
Force Sensing In Arthroscopic Instruments Using Fiber Bragg Gratings, Daniel S. Yurkewich
Force Sensing In Arthroscopic Instruments Using Fiber Bragg Gratings, Daniel S. Yurkewich
Electronic Thesis and Dissertation Repository
Minimally-invasive surgery has revolutionized many medical procedures; however, it also impedes the ability to feel the interaction between the surgical tool and the anatomical part being operated on. In order to address this problem, it is necessary to obtain accurate measurements of the interaction forces exerted on the surgical tools during surgery. These forces can then be manifested to the surgeon via a haptic device or presented visually (visual-force feedback). This thesis describes the use of a fiber optic device to measure and display to the surgeon interaction forces acting on an arthroscopic tool. The sensorization of the tool involves …
The Effect Of Cutting Blade Geometry And Material On Carbon Fiber Severing As Used In High-Volume Production Of Composites, Michael Francis Anthony Adamovsky
The Effect Of Cutting Blade Geometry And Material On Carbon Fiber Severing As Used In High-Volume Production Of Composites, Michael Francis Anthony Adamovsky
Electronic Thesis and Dissertation Repository
Automotive manufacturers have started to actively look into weight savings options for mass production of vehicles that meet new government regulations. Falling prices of carbon fibers have made carbon fiber composites a promising material to be used. The study has focused on the fiber-severing unit incorporated in a high-volume composite production line in an attempt to better define the impact of blade geometry and material on the wear as experienced while cutting carbon fiber. A method to quantify the effect of usage on the cutting ability of a blade has been developed, as well as methods to measure blade wear. …
Osteoarthritis Induced Glenoid Morphology And Bone Quality: An Evaluation Of Augmented Glenoid Components, Nikolas K. Knowles
Osteoarthritis Induced Glenoid Morphology And Bone Quality: An Evaluation Of Augmented Glenoid Components, Nikolas K. Knowles
Electronic Thesis and Dissertation Repository
Osteoarthritis of the glenoid results in regional bone density variations and bone loss that may compromise early component fixation and support. The two common morphologies, symmetric and asymmetric erosion, were characterized by bone density and morphology, and assessed on the basis of bone removal and bone quality in the context of augmented glenoid components. The bone strain field was also compared when different augmented glenoid components underwent simulated joint loading using finite element analysis.
Asymmetrically eroded glenoids were found to have denser bone (p
Characterization Of High-Pressure-Die-Cast Magnesium Alloy Am60, Hooman Baghaei Anaraki
Characterization Of High-Pressure-Die-Cast Magnesium Alloy Am60, Hooman Baghaei Anaraki
Electronic Thesis and Dissertation Repository
The primary goal of this study is the characterization of high pressure die cast magnesium alloys AM60 so that the failure model which is proposed by J.Weiler can be validated for two new castings. The input variables of failure model can be determined by characterization of different regions within the castings. Based on the location of gate system, the desired regions are identified across both castings and tensile specimens are extracted from various regions. Therefore the local mechanical properties are determined, and fracture strain of samples ranges from 1.2 to 9.5%. The area fraction of porosities and skin fraction of …
Thermal Convection In Non-Fourier Fluids And Application To Liquid Helium Ii, Mohammad Niknami Esfahani
Thermal Convection In Non-Fourier Fluids And Application To Liquid Helium Ii, Mohammad Niknami Esfahani
Electronic Thesis and Dissertation Repository
This thesis examines different conditions for which non-Fourier effects can be significant in the flow of fluids. Non-Fourier fluids of dual-phase-lagging type (DPL) possess a relaxation time and a retardation time, reflecting the delay in the response of the heat flux and the temperature gradient with respect to one another. For non-Fourier fluids of single-phase-lagging type (SPL) the retardation time is zero. Non-Fourier fluids span a wide range of applications, including liquid helium, nanofluids and rarefied gases. The parallels between non-Fourier fluids and polymeric solutions are established.
The instability of steady natural convection of a thin layer of non-Fourier fluid …