Physics Commons^™

Directional Tensile Strength Of Carbon Fiber Reinforced Polylactic Acid In Extrusion Based Additive Manufacturing For Custom Failure Parts, Lucinda Slattery

Honors College

Inherently, additive manufacturing printed parts have faults between layers perpendicular to the direction of printing, both in the plane parallel to the build plate and in the z direction (out of the build plate). For most parts, these “built-in” faults from the manufacturing process act as limiting conditions for the part's mechanical strength. While perpendicular to printing is typically the weakest due to layer adhesion faults, parallel to printing is typically the strongest due to cohesive material and fiber orientation. Fiber orientation can be measured through various methods, with the two explored being X-Ray Microscopy (XRM) for 3D analysis, and …

Thermal Stability Of Platinum-Silicon Alloy Films Grown On Langasite Substrates For Use In Microwave Acoustic Sensor Technology, Kell Fremouw

Honors College

Wireless sensors that can operate in temperatures up to 1000°C are widely needed for real time monitoring of large-scale industrial processes. Such sensors will improve efficiency and prevent component failure. Under previous work at UMaine, Surface Acoustic Wave Resonator (SAWR) sensors fabricated on piezoelectric langasite (La₃Ga₅SiO₁₄) wafers have shown promise for wireless strain measurements at high temperatures. However, there is a major technical challenge in attaching SAWR langasite based sensors to metal parts because the large differences in the coefficient of thermal expansion (CTE) between langasite and metals leads to large thermal stresses and …

Design, Construction, And Investigation Of A Small Polarimeter, Kelvy Zucca

Honors College

This project uses a custom polarimeter to measure the polarization of light we receive from stars. Most bright stars emit unpolarized radiation, so measuring non-zero polarization is significant. Even highly polarized stars only have degrees of polarization around five percent. Polarized light from a star may mean 1) the star is actually a binary system, 2) the star has a significant magnetic field, or 3) the star has some other feature or variability that is atypical of the majority of bright stars. A polarimeter is used to measure polarization. As the Jordan Observatory did not have a polarimeter, the project …

Investigating The Stability Of Observed Low Semi-Major Axis Exoplanetary Systems With Hypothetical Outer Planets Using The Program Mercury6, Kendall Butler

Honors College

This project investigates the stability of observed planetary systems, and whether this stability remains in the presence of additional outer planets. This made use of the program Mercury6, an n-body integrator that computes the changes in planetary orbits over time. The Systems HD 136352, GJ 9827, and HD 7924 were studied with initial conditions taken from the available observational data. This information was curated using the online NASA Exoplanet archive of confirmed exoplanets. With these initial conditions, Mercury6 computed the changing planetary orbits of each system for 5 million years. For each of these systems, a single outer planet, which …

Applying Cluster Analysis To Student Responses From Energy Surveys For Identification Of Commonalities In Their Understanding, Arianna Giguere

Honors College

Energy is a complicated model that has been developed to describe matter to matter interactions. Since energy can be challenging to define, there are inconsistencies among even teachers and physicists in how they define the concept. It is no wonder that students themselves carry misconceptions and confusions. While it may be difficult to teach, an understanding of energy from a young age is essential for the future of technology, climate change, and scientific discoveries. Middle school students in Maine are required to learn about energy transformation, conservation, and forms, and from 2011-2018, researchers at the University of Maine administered multiple …

Design And Construction Of A Computer Controlled Astronomical Spectropolarimeter, Jacob Marchio

Honors College

A theoretical description of a simple optical train, modulated signal based spectropolarimeter is discussed. The design includes, after the telescope optical tube (in this case, a 9.25” Schmidt Cassegrain), a rotating quarter waveplate (compensator), a fixed linear polarizer (analyzer), and transmission grating of 100l/mm, with a ZWO ASI290mm astronomical camera. The practical constraints on implementing such an instrument are discussed, and the construction of the spectropolarimeter is detailed, including the necessary optics, optomechanics, and electromechanics. The rotation and recording of the rotating compensator is facilitated by a motorized connection with proportional feedback control, and the uncertainty in measuring the angle …

Investigating Ions’ Effects On The Fluorescent Protein Dendra2, Benjamin Waterman

Honors College

While superresolution microscopy has opened the doors to insights into biological phenomena we couldn’t have dreamed of in the last century, its methodology is naturally limited. We aim to push the envelope of its capabilities by testing the effect that Ca2+ and H+ ions have on the fluorescent protein Dendra2. Utilizing a newly designed perfusion chamber, we flow separate solutions containing Ca2+ and H+ ions into a cellular environment, in which the cells in question have been tagged with Dendra2. Utilizing the superresolution technique known as Spectral Fluorescence Photoactivation Localization Microscopy, we are able to obtain information about the emission …

Antineutrino-Induced Charge Current Quasi-Elastic Neutral Hyperon Cross-Section On Argon In Argoneut, Samuel M. Borer

Honors College

This thesis outlines the first measurement of CCQE neutral hyperon production cross section in a liquid argon time projection chamber (LArTPC) through a topological study [1] and presents the ongoing progress of the addition of a calorimetric study. The analysis uses 1.20 £ 1020 protons-on-target, in the NuMI beam operating in the low energy antineutrino mode. The results of the topological study provide a total cross section measurement at the mean production energy of 3.42 GeV for CCQE neutral hyperons. The result of the topological study is consistent with the NUANCE cross section model and sets a 90% confidence level …

Probing The Nature Of Student Reasoning Using Modified Chaining Tasks, Ryan Moyer

Honors College

Research-based materials developed by the physics education research community have helped improve student conceptual understanding in introductory physics courses. A growing body of work, however, suggests that poor student performance on certain physics tasks, even after research-based instruction, may result from the nature of student reasoning itself than from conceptual difficulties. Drawing upon dual-process theories of reasoning, it has been argued that some of the poor performance from the presence of salient distracting features (SDFs) in physics problems, which may cue an incorrect first-available mental model and effectively preclude the student from drawing upon relevant knowledge.

In this study, we …

An Analysis Of Middle School Physical Science Teachers' Understanding Of Accelerated Motion, Elijah Tabachnick

Honors College

Continued observation of teachers within the University of Maine Physical Sciences Partnership showed persistence over many iterations of professional development (PD) the use of an inconsistent model of accelerated motion. This model identified acceleration in the same direction as velocity as positive (speeding up is defined as positive acceleration) and acceleration opposed to velocity as negative; we will call this the speed model. We found use of this model in middle school physical science teachers in a survey and through interviews. A PD activity was also observed to study the teachers’ use of vectors and coordinate systems to solve kinematics …

Ode To Applied Physics: The Intellectual Pathway Of Differential Equations In Mathematics And Physics Courses: Existing Curriculum And Effective Instructional Strategies, Brandon L. Clark

Honors College

The purpose of this thesis is to develop a relationship between mathematics and physics through differential equations. Beginning with first-order ordinary differential equations, I develop a pathway describing how knowledge of differential equations expands through mathematics and physics disciplines. To accomplish this I interviewed mathematics and physics faculty, inquiring about their utilization of differential equations in their courses or research. Following the interviews I build upon my current knowledge of differential equations in order to reach the varying upper-division differential equation concepts taught in higher-level mathematics and physics courses (e.g., partial differential equations, Bessel equation, Laplace transforms) as gathered from …

Examining Student Reasoning In Introductory Physics: Reversing The Chain, William S. Johnson

Honors College

While physics education researchers have investigated student conceptual understanding of specific topics in physics for over thirty years, much less is known about the ability of students to construct qualitative inferential reasoning chains. Such reasoning chains are ubiquitous in scaffolded, research-based instructional materials. As part of a multi-institutional effort to develop instruments to probe student reasoning skills, this thesis describes an investigation into whether the direction of a question can influence the ability of the students to construct correct reasoning chains. Reasoning reversal tasks were administered to introductory calculus-based physics students at the University of Maine. Students were randomly presented …

Stochastic Modeling Of Us Equity Returns, Mitchell Benoit

Honors College

A non-linear Langevin equation was constructed in order to approximate the behavior of the S&P 500 Index intraday price movements. Price changes were assumed to be a function of supply/demand offsets that resulted from new information. Based on this observation, I constructed an equation that describe the rate of return for the market data, which depended on (1) the sensitivity of the market to supply/demand offsets, (2) the liquidity of the market, (3) the memory effects of recent returns, and (4) the memory effects of the volatility of recent returns. MATLAB was used to find appropriate coefficients for these terms …

Application Of Parallel Computing To Optimize Studies Of Critical Exponents In The One-Dimensional Sznajd Model, Joseph Garcia

Honors College

The Sznajd model (SM) is a one-dimensional voter-like model used to study consensus in systems where information flows outward from like-minded neighboring agents. Here, we introduce long-range interactions to the SM via the parameter p, where p→1 is the mean-field limit (MFL) and p→0 the one-dimensional limit (1DL). Using Monte Carlo simulations and finite size scaling analyses to characterize the exit probability for p > 0, we find a step function reliant on two p-dependent exponents. By examining the exponents' behavior in the 1DL, we comment on the functional form of the exit probability in one dimension—its nature …

A Lateral Field Excited Thin Film Bulk Acoustic Wave Sensor, Michael R. Fitzgerald

Honors College

Medical and environmental needs have served as a catalyst for the development of sensors that can probe the molecular level and below. This study addresses the practicality of highly sensitive aluminum nitride (AlN) thin film bulk acoustic wave resonators (FBARs) as sensors from theoretical and experimental points of view. Theoretically, COMSOL Multiphysics simulations predict that lateral field excitation of AlN produces an electric field perpendicular to the c-axis, with the electrical energy density being concentrated in the active area of the sensor. An analysis of the piezoelectrically stiffened Christoffel equation shows that the shear mode can be excited by an …