Engineering Commons^™

Development Of Novel Models To Study Deep Brain Effects Of Cortical Transcranial Magnetic Stimulation, Farheen Syeda

Theses and Dissertations

Neurological disorders require varying types and degrees of treatments depending on the symptoms and underlying causes of the disease. Patients suffering from medication-refractory symptoms often undergo further treatment in the form of brain stimulation, e.g. electroconvulsive therapy (ECT), transcranial direct current stimulation (tDCS), deep brain stimulation (DBS), or transcranial magnetic stimulation (TMS). These treatments are popular and have been shown to relieve various symptoms for patients with neurological conditions. However, the underlying effects of the stimulation, and subsequently the causes of symptom-relief, are not very well understood. In particular, TMS is a non-invasive brain stimulation therapy which uses time-varying magnetic …

Predator-Prey Game To Maintain Stable Fish Population For Ecotoxicological Studies, Jason Blondin, Catherine Halpern, Tyler Malkus

Capstone Design Expo Posters

With the state of the environment on the forefront of many minds today, it’s important for our society to be able to understand how we interact with our local ecosystems and the potential impacts we can cause. Creating computational simulations of these environments can help to predict the possible effects of different situations. The purpose of our project was to create a predator-prey simulation of different species of fish that could take into account different population management strategies and accurately reflect the waves that could be caused by the introduction of various chemicals into the fish’s environment.

In order to …

Measurements And Modeling Of Hydrocarbon Mixture Fluid Properties Under Extreme Temperature And Pressure Conditions, Babatunde A. Bamgbade

Theses and Dissertations

Knowledge of thermodynamic fluid properties, such as density and phase behavior, is important for the design, operation, and safety of several processes including drilling, extraction, transportation, and separation that are required in the petroleum. The knowledge is even more critical at extreme temperature and pressure conditions as the search for more crude oil reserves lead to harsher conditions. Currently, there is dearth of experimental data at these conditions and as such, the predictive capability of the existing modeling tools are unproven. The objective of this research is to develop a fundamental understanding of the impact of molecular architecture on fluid …

Micro- And Macro-Scale Modeling Of Filter Aging: Effects Of Particle Poly-Dispersity And Fiber Cross-Sectional Shape, Ahmed M. Saleh

Theses and Dissertations

The goal of this study is to further advance the state of the art in developing self-sufficient methods to predict the performance of an aerosol filter. The simulation methods developed in this study are based on first principles and consequently, they do not rely on empirical correction factors. These simulation methods can be used to predict the instantaneous collection efficiency and pressure drop of a filter under dust-loading conditions. In the current study, 3-D micro- and macroscale CFD models are developed to simulate the service life of flat-sheet and pleated filters. These CFD micro- and macroscale models are also used …

The Design And Validation Of A Computational Rigid Body Model For Study Of The Radial Head, Cassandra Woodcock

Theses and Dissertations

Rigid body modeling has historically been used to study various features of the elbow joint including both physical and computational models. Computational modeling provides an inexpensive, easily customizable, and effective method by which to predict and investigate the response of a physiological system to in vivo stresses and applied perturbations. Utilizing computer topography scans of a cadaveric elbow, a virtual representation of the joint was created using the commercially available MIMICS(TM) and SolidWorks(TM) software packages. Accurate 3D articular surfaces, ligamentous constraints, and joint contact parameters dictated motion. The model was validated against two cadaveric studies performed by Chanlalit et al. …

The Design And Validation Of A Computational Model Of The Human Wrist Joint, Afsarul Mir

Theses and Dissertations

Advancements in computational capabilities have allowed researchers to turn towards modeling as an efficient tool to replicate and predict outcomes of complex systems. Computational models of the musculoskeletal system have gone through various iterations with early versions employing dramatic simplifications. In this work, a three-dimensional computational model of the wrist joint was developed. It accurately recreated the skeletal structures of the hand and wrist and represented the constraints imposed by soft tissue structures like ligaments, tendons, and other surrounding tissues. It was developed to function as a tool to investigate the biomechanical contributions of structures and the kinematic response of …

Accelerating Finite State Projection Through General Purpose Graphics Processing, Thomas Trimeloni

Theses and Dissertations

The finite state projection algorithm provides modelers a new way of directly solving the chemical master equation. The algorithm utilizes the matrix exponential function, and so the algorithm’s performance suffers when it is applied to large problems. Other work has been done to reduce the size of the exponentiation through mathematical simplifications, but efficiently exponentiating a large matrix has not been explored. This work explores implementing the finite state projection algorithm on several different high-performance computing platforms as a means of efficiently calculating the matrix exponential function for large systems. This work finds that general purpose graphics processing can accelerate …

Dual-Scale Modeling Of Two-Phase Fluid Transport In Fibrous Porous Media, Alireza Ashari

Theses and Dissertations

The primary objective of this research is to develop a mathematical framework that could be used to model or predict the rate of fluid absorption and release in fibrous sheets made up of solid or porous fibers. In the first step, a two-scale two-phase modeling methodology is developed for studying fluid release from saturated/unsaturated thin fibrous media made up of solid fibers when brought in contact with a moving solid surface. Our macroscale model is based on the Richards’ equation for two-phase fluid transport in porous media. The required constitutive relationships, capillary pressure and relative permeability as functions of the …

Analysis And Shape Modeling Of Thin Piezoelectric Actuators, Makram Mouhli

Theses and Dissertations

The field of smart materials is an increasingly growing area of research. In aerodynamics applications especially, transducers have to fulfill a series of requirements such as light weight, size, energy consumption, robustness and durability. Piezoelectric transducers, devices which transform an electrical signal into motion, fulfill many of these requirements. Specifically, piezoelectric composites are of interest due to their added toughness and ease of integration into a structure. Resulting composites have a characteristic initial curvature with accompanying residual stresses that are responsible for enhanced performance, relative to flat actuators, when the active material is energized. A number of transducer designs based …

Numerical Modeling Of Synthetic Jets In Quiescent Air With Moving Boundary Conditions, Nicholas D. Castro

Theses and Dissertations

Flow control is a key factor in optimizing the performance of any vehicle moving through fluids. Particularly, in aerodynamics there are many potential benefits for implementing synthetic jets to achieve aircraft designs with less moving parts, uper- maneuverability, and separation control for fuel economy. Piezoelectric synthetic jets are of special interest because of their lightweight and low power consumption. Numerous publications on such jets are available. Actuator properties and boundary conditions relevant to this particular application however are often overlooked. The focus of this project is to numerically model synthetic jets in quiescent air to study the influence of cavity …