Physical Sciences and Mathematics Commons^™

Design And Evaluation Of Miniaturized Ion Trap Mass Analyzers Using Simulation, Radhya Weligama Gamage

Theses and Dissertations

Mass spectrometry is a technique that analyzes the chemical compositions of compounds based on the mass-to-charge ratio of their ionized constituents. Miniaturized ion trap mass spectrometry finds application in a wide range of fields where portable, rugged, and reliable analytical instruments are required. Ion traps of various designs have been introduced over the past decades, each with their own unique advantages and capabilities. However, the process of developing a novel miniaturized ion trap mass spectrometer continues to be fraught with challenges. This dissertation discusses simulation studies pertaining to the development of a novel dual ion trap, the simplified coaxial ion …

Implementing A High-Performance Quantum Computing Emulator, Reece Robertson

Undergraduate Honors Theses

We implement a quantum computing emulator after the manner described by Häner et al. with the goal of temporal and spatial savings. The emulator is compared to the Intel Quantum Simulator to verify speedup and spatial savings over the simulator method. We also implement Shor's algorithm in the emulator and use it to solve a nontrivial factoring problem. This demonstrates that the emulator makes quantum computing more accessible on at least two accounts: it allows users to solve nontrivial problems quickly and it provides those looking to enter quantum computing with an accessible place to start. Finally, we outline future …

Evaluating An Educational Cybersecurity Playable Case Study, Tanner West Johnson

Theses and Dissertations

The realities of cyberattacks have become more and more prevalent in the world today. Due to the growing number of these attacks, the need for highly trained individuals has also increased. Because of a shortage of qualified candidates for these positions, there is an increasing need for cybersecurity education within high schools and universities. In this thesis, I discuss the development and evaluation of Cybermatics, an educational simulation, or playable case study, designed to help students learn and develop skills within the cybersecurity discipline.

This playable case study was designed to allow students to gain an understanding of the field …

A Coverage Metric To Aid In Testing Multi-Agent Systems, Jane Ostergar Linn

Theses and Dissertations

Models are frequently used to represent complex systems in order to test the systems before they are deployed. Some of the most complicated models are those that represent multi-agent systems (MAS), where there are multiple decision makers. Brahms is an agent-oriented language that models MAS. Three major qualities affect the behavior of these MAS models: workframes that change the state of the system, communication activities that coordinate information between agents, and the schedule of workframes. The primary method to test these models that exists is repeated simulation. Simulation is useful insofar as interesting test cases are used that enable the …

The Pseudo-Rigid-Body Model For Fast, Accurate, Non-Linear Elasticity, Anthony R. Hall

Theses and Dissertations

We introduce to computer graphics the Pseudo-Rigid-Body Mechanism (PRBM) and the chain algorithm from mechanical engineering, with a unified tutorial from disparate source materials. The PRBM has been used successfully to simplify the simulation of non-linearly elastic beams, using deflections of an analogous spring and rigid-body linkage. It offers computational efficiency as well as an automatic parameterization in terms of physically measurable, intuitive inputs which fit naturally into existing animation work flows for character articulation. The chain algorithm is a technique for simulating the deflection of complicated elastic bodies in terms of straight elastic elements, which has recently been extended …

American Spread Option Models And Valuation, Yu Hu

Theses and Dissertations

Spread options are derivative securities, which are written on the difference between the values of two underlying market variables. They are very important tools to hedge the correlation risk. American style spread options allow the holder to exercise the option at any time up to and including maturity. Although they are widely used to hedge and speculate in financial market, the valuation of the American spread option is very challenging. Because even under the classic assumptions that the underlying assets follow the log-normal distribution, the resulting spread doesn't have a distribution with a simple closed formula. In this dissertation, we …

Optimized Simulation Of Granular Materials, Seth R. Holladay

Theses and Dissertations

Visual effects for film and animation often require simulated granular materials, such as sand, wheat, or dirt, to meet a director's needs. Simulating granular materials can be time consuming, in both computation and labor, as these particulate materials have complex behavior and an enormous amount of small-scale detail. Furthermore, a single cubic meter of granular material, where each grain is a cubic millimeter, would contain a billion granules, and simulating all such interacting granules would take an impractical amount of time for productions. This calls for a simplified model for granular materials that retains high surface detail and granular behavior …

Performance Evaluation Of Optimal Rate Allocation Models For Wireless Networks, Ryan Michael Padilla

Theses and Dissertations

Convex programming is used in wireless networks to optimize the sending or receiving rates of links or flows in a network. This kind of optimization problem is formulated into a rate allocation problem, where each node in the network will distributively solve the convex problem and all links or flows will converge to their optimal rate. The objective function and constraints of these problems are represented in a simplified model of contention, interference, and sending or receiving rates. The Partial Interference model is an optimal rate allocation model for use in wireless mesh networks that has been shown to be …

Using Agent-Based Models To Understand Multi-Operator Supervisory Control, Yisong Guo

Theses and Dissertations

As technology advances, many practical applications require human-controlled robots. For such applications, it is useful to determine the optimal number of robots an operator should control to maximize human efficiency given different situations. One way to achieve this is through computer simulations of team performance. In order to factor in various parameters that may affect team performance, an agent-based model will be used. Agent-based modeling is a computational method that enables a researcher to create, analyze, and experiment with models composed of agents that interact within an environment [12]. We construct an agent-based model of humans interacting with robots, and …

Simulating The Fticr-Ms Signal Of A Decaying Beryllium-7 Ion Plasma In A 2d Electrostatic Pic Code, Michael Takeshi Nakata

Theses and Dissertations

Beryllium-7 (Be-7) only decays by electron capture into lithium-7 (Li-7) with a half life of 53 days. We study the effect of ionization on this decay rate. We do so by trapping a Be-7 ion plasma in a cylindrical Malmberg-Penning trap and measuring Be-7 and Li-7 concentrations as functions of time by using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). We have simulated these signals in a 2-dimensional electrostatic particle-in-cell (PIC) code. The two spectrum peaks merge at high ion densities whereas at low ion densities they can be resolved. The merged peak shifts linearly according to the relative …

Measurement And Simulation Of Laser-Induced Fluorescence From Nonequilibrium Ultracold Neutral Plasmas, A. Denning, Scott D. Bergeson, F. Robicheaux

Faculty Publications

We report measurements and simulations of laser-induced fluorescence in ultracold neutral plasmas. We focus on the earliest times, when the plasma equilibrium is evolving and before the plasma expands. In the simulation, the ions interact via the Yukawa potential in a small cell with wrapped boundary conditions. We solve the optical Bloch equation for each ion in the simulation as a function of time. Both the simulation and experiment show the initial increase in ion fluorescence, disorder-induced heating, and coherent oscillation of the rms ion velocity. Detailed modeling of the fluorescence signal makes it possible to use fluorescence spectroscopy to …

Simulation And Visualization Of Environments With Multidimensional Time, Luther A. Tychonievich

Theses and Dissertations

This work introduces the notion of computational hypertime, or the simulation and visualization of hypothetical environments possessing multidimensional time. An overview of hypertime is provided,including an intuitive visualization paradigm and a discussion of the failure of common simulation techniques when extended to include multidimensional time. A condition for differential equations describing hypertime motion to be amenable to standard time-iterative simulation techniques is provided,but is not satisfied by any known model of physics. An alternate simulation algorithm involving iterative refinement of entire equations of motion is presented,with an example implementation to solve elastic collisions in hypertime. An artificial intelligence algorithm for …

An Adaptive Bayesian Approach To Bernoulli-Response Clinical Trials, Andrew W. Stacey

Theses and Dissertations

Traditional clinical trials have been inefficient in their methods of dose finding and dose allocation. In this paper a four-parameter logistic equation is used to model the outcome of Bernoulli-response clinical trials. A Bayesian adaptive design is used to fit the logistic equation to the dose-response curve of Phase II and Phase III clinical trials. Because of inherent restrictions in the logistic model, symmetric candidate densities cannot be used, thereby creating asymmetric jumping rules inside the Markov chain Monte Carlo algorithm. An order restricted Metropolis-Hastings algorithm is implemented to account for these limitations. Modeling clinical trials in a Bayesian framework …

A Simulation-Based Approach For Evaluating Gene Expression Analyses, Carly Ruth Pendleton

Theses and Dissertations

Microarrays enable biologists to measure differences in gene expression in thousands of genes simultaneously. The data produced by microarrays present a statistical challenge, one which has been met both by new modifications of existing methods and by completely new approaches. One of the difficulties with a new approach to microarray analysis is validating the method's power and sensitivity. A simulation study could provide such validation by simulating gene expression data and investigating the method's response to changes in the data; however, due to the complex dependencies and interactions found in gene expression data, such a simulation would be complicated and …

A Selective Approach To Bandwidth Overbooking, Feng Huang

Theses and Dissertations

Overbooking is a technique used by network providers to increase bandwidth utilization. If the overbooking factor is chosen appropriately, additional virtual circuits can be admitted without degrading quality of service for existing customers. Most existing implementations use a single factor to accept a linear fraction of traffic requests. High values of this factor may cause the degradation of quality of service whereas low overbooking factors will result in underutilization of bandwidth. Network providers often select overbooking factors based only on aggregate average virtual circuit utilization. This paper proposes a selective overbooking scheme based on trunk size and usage profile. Experiments …