Engineering Commons^™

An Algorithm To Recognize Multi-Stable Behavior From An Ensemble Of Stochastic Simulation Runs, Eduardo Monzon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synthetic biological designers are demanding tools to help with the design and verification process of new biological models. Some of the most common tools available aggregate multiple simulation results into one “clean” trajectory that hopefully is representative of the system’s behavior. However, for systems exhibiting multiple stable states, these techniques fail to show all the possible trajectories of the system. This work introduces a method capable of detecting the presence of more than one “typical” trajectory in a system, which can also be integrated with other available simulation tools.

Effects Of Communication Delay And Kinematic Variation In Vehicle Platooning, Megan R. Emmons

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Vehicle platoons are efficient, closely-spaced groups of robotically controlled vehicles which travel at high speeds down the road, similar to carts in a train. Within this thesis, a promising control algorithm for vehicle platooning is explored. The control algorithm was previously demonstrated in a sterile setting which significantly reduced the challenges facing full-scale implementation of platoons, most notably loss of shared data and imprecision within the data.

As found within this work, transmission loss and imprecise position, velocity, and acceleration data significantly degraded the control algorithm's performance. Vehicles in the platoon became more closely spaced, changed speeds more frequently, and …

Digital Microfluidics As A Reconfiguration Mechanism For Antennas, Yasin Damgaci

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The properties of conventional antennas are fixed by the initial design and cannot be changed. A reconfigurable antenna, on the other hand, can dynamically change its properties, and it can adjust its behavior for a given propagation condition. This dissertation work concentrates on novel reconfiguration technologies, including design, microfabrication, and characterization aspects with an emphasis on their applications to multifunctional reconfigurable antennas. In the literature, reconfigurable antennas have made use of various reconfiguration techniques. The most common techniques utilized revolved around switching mechanisms. Other techniques such as the incorporation of variable capacitors, varactors, and physical structure manipulation surfaced recently to …

The Design And Implementation Of The Dynamic Ionosphere Cubesat Experiment (Dice) Science Instruments, Steven Reed Burr

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dynamic Ionosphere Cubesat Experiment (DICE) is a cubesat satellite project funded by the National Science Foundation (NSF) to study the ionosphere. Cubesats are small satellites in the shape of a cube around 10cm on a side, and allow better access to space. Three main properties of the ionosphere are measured by the DICE mission, which are electric field, magnetic field, and plasma density with an instrument for each. The limitation of power, mass, and volume contributes to the difficulty of cubesat design. Mission and instrumentation requirements must be carefully planned to ensure mission success. Each instrument’s requirements and design are …

Transparent Antennas For Solar Cell Integration, Tursunjan Yasin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Transparent patch antennas have a certain level of optical transparency. Highly transparent patch antennas can be integrated with the solar panels of small satellites, which are becoming increasingly important in space exploration. Traditional patch antennas, which are not transparent, are employed on small satellites and compete with solar cells for surface area. But a transparent patch antenna can be placed directly on top of the solar cells and alleviate the issue of limited surface real estate. For such an integration, a high optical transparency of the patch antenna is required from the solar cells’ point of view since the solar …

Cognitive Vehicle Platooning In The Era Of Automated Electric Transportation, Pooja Kavathekar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research focuses on a concept called “cognitive vehicle platooning.” A group of vehicles, either of the same type or different, following one another at highway speeds, coupled together by wireless communication is vehicle platooning. With this technology, passengers can comfortably enjoy their rides without having to drive their cars, as the cars will drive themselves. This automatic car driving is an advanced form of cruise control. These cars will run on dedicated lanes on highways. The leader of the platoon communicates wirelessly to its followers, its position, velocity, and acceleration information. Using this data, the followers will have a …

Extracting Atmospheric Profiles From Hyperspectral Data Using Particle Filters, Dustin Rawlings

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Removing the effects of the atmosphere from remote sensing data requires accurate knowledge of the physical properties of the atmosphere during the time of measurement. There is a nonlinear relationship that maps atmospheric composition to emitted spectra, but it cannot be easily inverted. Inverting this relationship, however, would allow us to estimate atmospheric parameters by taking hyperspectral measurements of the light emitted from the atmosphere. The particle filter is a method whereby one can estimate a hidden system state based on measurements, without ever having to directly invert the measurement relationship.

Traditionally, particle filters do not perform well in high-dimensional …

The Contribution Of Magnetospheric Currents To Ground Magnetic Perturbation During Geomagnetic Storms, Swadesh Patra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A geomagnetic storm is a disturbance in the earth's space environment in response to a disturbance in the solar wind. The earth's ring current that is a toroidal current flowing roughly in the region also occupied by the Van-Allen radiation belt is energized during a geomagnetic storm. This leads to a decrease in the horizontal component of the geomagnetic field on the earth's surface. The Disturbance Storm Time (Dst) index, which is a measure of the intensity of the ring current, is calculated by taking the average of this decrease in the horizontal intensity across four low latitude …

Correcting Errors Due To Species Correlations In The Marginal Probability Density Evolution Algorithm, Abiezer Tejeda

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synthetic biology is an emerging field that integrates and applies engineering design methods to biological systems. Its aim is to make biology an “engineerable” science. Over the years, biologists and engineers alike have abstracted biological systems into functional models that behave similarly to electric circuits, thus the creation of the subfield of genetic circuits. Mathematical models have been devised to simulate the behavior of genetic circuits in silico. Most models can be classified into deterministic and stochastic models. The work in this dissertation is for stochastic models.

Although ordinary differential equation (ODE) models are generally amenable to simulate genetic …

Determination Of Ionospheric Current Systems By Measuring The Phase Shift On Amateur Satellite Frequencies, Prajwal M. Kasturi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Linearly polarized electromagnetic waves traveling through cold magnetized plasma experience Faraday rotation. The Appleton Hartree dispersion equation relates the phase shift on any electromagnetic ray to the magnetic field B, ion-electron density N_e and the angle the ray makes with the instantaneous magnetic field. This work uses the dispersion relation to calculate small time scale magnetic perturbations in the ionosphere due to electrojet current systems. The ionosphere is modeled as a collision free cold plasma with synthesized small scale magnetic perturbations. The work presented here simulates test cases, where the satellites transmits three amateur satellite radio band frequencies …

Evolutionary Optimization Algorithms For Nonlinear Systems, Ashish Raj

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the real world, we encounter a number of problems which require iterative methods rather than heuristic approaches to solve them. Not every problem can be solved with a definitive method. Optimization algorithms come to the aid of such instances. These algorithms carry out multiple iterations or generations to try to achieve the lowest value of a cost function. The demand for fast and robust stochastic algorithms to cater to the optimization needs is very high. The faster the convergence to a low value of the cost function, the better the algorithm is. This is attained in greedy criterion approaches, …

Thermo-Piezo-Electro-Mechanical Simulation Of Algan (Aluminum Gallium Nitride) / Gan (Gallium Nitride) High Electron Mobility Transistor, Lorin E. Stevens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to the current public demand of faster, more powerful, and more reliable electronic devices, research is prolific these days in the area of high electron mobility transistor (HEMT) devices. This is because of their usefulness in RF (radio frequency) and microwave power amplifier applications including microwave vacuum tubes, cellular and personal communications services, and widespread broadband access. Although electrical transistor research has been ongoing since its inception in 1947, the transistor itself continues to evolve and improve much in part because of the many driven researchers and scientists throughout the world who are pushing the limits of what modern …

Optical Sensors For Mapping Temperature And Winds In The Thermosphere From A Cubesat Platform, Stephanie Whalen Sullivan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the same way that mariners desire to know the weather their ships are about to encounter, satellite owners would like to know the conditions along their satellites' orbits. Accurate forecasts would allow operators to secure sensitive components prior to passing through a storm to reduce the risk of damage. Large solar arrays, which can act like sails, can be re-oriented to prevent the satellite from being moved out of its desired orbit. While terrestrial weather forecasters have thousands of sensors with continuous data streams available to generate weather models, very few sensors exist for space weather. Cost of sensing …

Secure Localization Topology And Methodology For A Dedicated Automated Highway System, Bhaswati Deka

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In today’s fast-paced world, mobility is a very important factor in improving the quality of living. The purpose of an automated transportation system (ATS) is to provide mobility to one and all, irrespective of their capabilities. An ATS requires a lot of planning to be efficient and safe for public use. One of the main aspects of safety is to determine the location of the individual vehicles within the system and ensure that their location is not posing any hazard to other vehicles in the system or any other entity outside the system. The process of determining or verifying the …

Using Electromagnetic Induction Sensing To Understand The Dynamics And Interacting Factors Controlling Soil Salinity, Xystus N. Amakor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High amounts of salts in soils and a greater tendency of these soils to become even more saline is of great concern in arid and semi-arid western United States. Soils in Cache County, Utah are no exception. Salinization negatively affects the soil, crop, and the quality of groundwater. Thus, the long-term sustainable management of irrigated agricultural lands is threatened.

However, the salinity of these soils are closely monitored and managed to ensure sustainable agricultural productivity. A widely accepted and traditional standard method for estimating soil salinity is by measuring electrical conductivity of saturated paste extracts. Apart from the tedious and …

Micro-Electro-Mechanical Systems (Mems) Integrated Frequency Reconfigurable Antenna, Abdul Zohur

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis investigates the concept of reconfigurability of an antenna’s properties, such as frequency, radiation pattern, and polarization, for a planar inverted-F antenna (PIFA), by the use of radio frequency micro-electro-mechanical system (RF MEMS) switches. This research work has been conducted at the Micro/Nano Electro Mechanical Systems (µN _eMS) Laboratory at Utah State University. In this thesis, two electrically small frequency reconfigurable antenna designs have been presented with two and three modes of operation with central frequencies of 718 and 4960 MHz and of 857,809 and 4960 MHz, respectively. The maximum frequency tunable ratio achieved in these designs …

Safety Aware Platooning Of Automated Electric Transport Vehicles, Spencer Scott Jackson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Safety is a paramount concern when considering implementation of an automated highway where computers control the vehicles. Even with computer-fast reaction time there is inevitably some delay and if vehicles do not follow at safe distances, emergency braking maneuvers can cause dangerous collisions. This research investigates situations that might make automated vehicles have dangerous collisions and what standards the system design must hold to keep passengers safe.