Classical Electromagnetic Fields from Quantum Sources in Heavy-Ion Collisions

Electromagnetic fields are generated in high energy nuclear collisions by spectator valence protons. These fields are traditionally computed by integrating the Maxwell equations with point sources. One might expect that such an approach is valid at distances much larger than the proton size and thus such a classical approach should work well for almost the entire interaction region in the case of heavy nuclei. We argue that, in fact, the contrary is true: due to the quantum diffusion of the proton wave function, the classical approximation breaks down at distances of the order of the system size. We compute the electromagnetic field created by a charged particle described initially as a Gaussian wave packet of width 1 fm and evolving in vacuum according to the Klein-Gordon equation. We completely neglect the medium effects. We show that the dynamics, magnitude and even sign of the electromagnetic field created by classical and quantum sources are different.Comment: 12 pages, 4 figures. V2: a numerical error corrected, figures improved, other minor improvement

A Comprehensive Analysis of the Accounting Environment and Procedures Through a Series of Case Studies

The following thesis is a culmination of twelve case studies completed throughout the academic year of 2018-2019 under the direction of Dr. Victoria Dickinson, as a requirement of the Sally McDonnell Barksdale Honors College and completion of the ACCY 420 course. Each case study is independent of the next, and is an in-depth response to questions and theories that are found outside of this document. Each analysis is accomplished by myself alone and through the studies of Financial, Managerial, and Cost accounting courses in my career at the University of Mississippi. The thesis is intended to analyze accounting procedures and the current general accounting environment and topics. Accountants’ play a crucial role in the global economy, establishing trust and assurance through analytical and conceptual research and procedures. This thesis below illuminates several accounting problems, procedures, and questions posed by entities such as WorldCom, Starbucks, BP, and others. Besides the technical cases, other such as Case Study 1 and Case Study 5 are personal accounts of the accounting space and its impact on daily life and the economy. Rapid change in technology, corporations, and industries equate to an equally drastic adaption of public accountants. Computer software importance is quickly increasing and becoming more necessary as a basic skill for accountants. Overall, this thesis is intended to educate the reader on the ever-changing accounting world and how accountants are solving problems as quickly as the appear. This thesis, completed during coursework for ACCY 420, created multiple skills necessary for an accountant in either Audit, Tax, or Management Consulting. Research, critical thinking, public speaking, and professional writing/communication are just a few skills that were improved and acquired through the creation of this thesis

Towards a Theory and Practice of Translingual Transfer: A Study of 6 International Undergraduate Students

This dissertation brings together research on writing transfer and translingual views of writing through a description of the experiences of six international transfer students during their first semester at an American research university. This work pays special attention to the wide range of knowledges and practices that such students bring to new writing situations, broadening the definition of what might constitute a prior text in discussions of transfer. Findings from this study illustrate the ways that students do not simply import writing practices from one context to another, unchanged, but recontextualize them to suit the needs of new audiences, situations, languages, and genres. Of particular importance is these students’ recontextualization of the metalanguages they learn to associate with given contexts and kinds of writing. These metalanguages correspond to the language ideologies that pervade particular contexts and often structure the silos into which particular languages and practices are artificially bounded. Students’ recontextualization and blending of such metalanguages illustrates a potential for more fluid ways of conceptualizing writing across a range of contexts. This potential is displayed in these students’ negotiation of writing practices they bring to new situations from their math courses, and through their negotiation of institutional pressures that actively discourage effective transfer of knowledge and practices. Taken together, these findings suggest that a translingual approach offers new avenues to discussions of writing transfer, shifting from questions focused on whether or not students effectively draw on prior knowledges to questions focused on how better to identify and understand the inevitable interaction of the many knowledges and practices students encounter as they move across a wide range of contexts. This shift in focus further suggests potential changes for both researchers and teachers, who might come to better recognize and build upon the rich repertoires that students bring to classes by adopting a translingual approach to transfer.PHDEnglish & EducationUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/163177/1/ryanmcca_1.pd

Networks of strong ties

Social networks transmitting covert or sensitive information cannot use all ties for this purpose. Rather, they can only use a subset of ties that are strong enough to be ``trusted''. In this paper we consider transitivity as evidence of strong ties, requiring that each tie can only be used if the individuals on either end also share at least one other contact in common. We examine the effect of removing all non-transitive ties in two real social network data sets. We observe that although some individuals become disconnected, a giant connected component remains, with an average shortest path only slightly longer than that of the original network. We also evaluate the cost of forming transitive ties by deriving the conditions for the emergence and the size of the giant component in a random graph composed entirely of closed triads and the equivalent Erdos-Renyi random graph.Comment: 10 pages, 7 figure

Beyond Nationalism: James and Grace Lee Boggs and the Black Radical Tradition in 1980s Detroit

This paper explores the Black Radical Tradition in the 1980s through the lens of James and Grace Lee Boggs and their dedication to grassroots, community organizing and evolving revolutionary rhetoric. Existing scholarship on the decade is largely dedicated to the dialectic fluctuation of Black Power ideology and liberal reform that created a more conservative political agenda centered around partisan politics. Alternatively, the activism of James and Grace Lee Boggs in the immediate aftermath of the Black Power Era presents a complex view of the decade, providing space for black radicalism. The adaptation of the couple’s theories and mobilization strategies serve as a case study of the Black Radical tradition from the 1950s through the mid-1970s. Simultaneously, their continued activism and wholesale rejection of partisan politics in the late 1970s and 1980s charts a new path of study for black radicalism and black solidarity after the State sanctioned decimation of the Black Power Movement and the unofficial death of radicalism. James and Grace Lee’s grassroots organizing demonstrates a continuation of the Black Radical Tradition, evolved to fit contemporary circumstances. Their preservation of radical rhetoric in the 1980s disputes the consensus that black radicalism was wholly replaced by electoral mobilization. The couple’s extra-political radicalism adds nuance to the African-American experience of the 1980s, demonstrating the variety of African-American resistance to the rise of American conservatism

From small molecules to macromolecules : design, synthesis, and evaluation of functional organic materials

The incorporation of electronic device technology into our everyday lives has become an unavoidable reality in today’s connected world. Getting to this point has taken countless ingenious measures by scientists and engineers dedicated to increasing the speed and efficiency of the microelectronic devices that power many of the tools we rely on every day. For more than 50 years, the microelectronics industry has successfully manufactured generations of devices by shrinking the transistors on their chips. This shrinkage was made possible by improvements in photolithography. However, the physical limits to the resolution of lithography has now been reached leading leaving the microelectronic industry to employ costly and inefficient double patterning processes, which are expensive and unsustainable to extend the resolution of photolithography in high-volume manufacturing. Many question whether the ever cheaper and faster demand can continue. This dilemma has inspired the exploration at alternative patterning processes, one of which is the directed self-assembly (DSA) of block-copolymers (BCPs). Through careful and judicious design, the self-assembly of BCPs allows access to sub-5 nm features which are inaccessible by all current photolithographic technologies. While there has been extensive work done on the DSA of BCPs to produce aligned, lamellae in thin films, there is still a need for improvement in this field. Forming BCP films with a thickness on the order of their domain size and transferring the patterns formed by self-assembled BCPs into useful substances by reactive ion etching (RIE) is one area that requires more thorough investigation. Several strategies have been devised to impart some degree of etch-selectivity to one of the domains of a BCPs. One such strategy, which will be the focus of the work presented in this dissertation is the selective formation of a metal-oxide etch mask in one of the polymer domains of a BCPs. The development of a suitable BCP candidate will be presented as well as the results of several studies on vapor-phase infiltration processes. The challenges and discoveries made will be presented throughout this work.Chemistr

Low Thrust Cis-Lunar Transfers Using a 40 kW-Class Solar Electric Propulsion Spacecraft

This paper captures trajectory analysis of a representative low thrust, high power Solar Electric Propulsion (SEP) vehicle to move a mass around cis-lunar space in the range of 20 to 40 kW power to the Electric Propulsion (EP) system. These cis-lunar transfers depart from a selected Near Rectilinear Halo Orbit (NRHO) and target other cis-lunar orbits. The NRHO cannot be characterized in the classical two-body dynamics more familiar in the human spaceflight community, and the use of low thrust orbit transfers provides unique analysis challenges. Among the target orbit destinations documented in this paper are transfers between a Southern and Northern NRHO, transfers between the NRHO and a Distant Retrograde Orbit (DRO) and a transfer between the NRHO and two different Earth Moon Lagrange Point 2 (EML2) Halo orbits. Because many different NRHOs and EML2 halo orbits exist, simplifying assumptions rely on previous analysis of orbits that meet current abort and communication requirements for human mission planning. Investigation is done into the sensitivities of these low thrust transfers to EP system power. Additionally, the impact of the Thrust to Weight ratio of these low thrust SEP systems and the ability to transit between these unique orbits are investigated

Examining and Expanding the Impact of Practice-Based Teacher Education at National Louis University Faculty Research Residency Final Report 2017-18

This study investigated the perceptions about literacy preparation of recent graduates from NLU’s multiple teacher preparation programs. Specifically, the researchers surveyed NLU students who graduated between 2014-17 to determine which literacy concepts/practices they felt were most important in their first year of teaching and how well prepared they were to teach those concepts/practices. In addition, graduates were asked to consider the instructional practices they encountered during their NLU coursework and whether these practices were helpful in learning to teach literacy. Graduates were also asked to consider how well prepared they were to teach literacy in general. Initial analysis of data led the researchers to conclude the following: 1) Perception of preparedness varies by programs, with students in programs that implement more practice-based literacy learning reporting far better preparedness than students in the other programs; 2) Across programs, students find practice-based classroom experiences to be more helpful than more traditional experiences; 3) In several programs, high numbers of respondents did not appear to have opportunities to teach literacy with actual P-12 students; 4) Though there are some literacy practices that graduates seemed relatively well-prepared to teach, there are gaps between perception of importance of literacy practices and how well prepared our graduates felt to teach them. In particular, in the areas of writing, classroom discussion, and comprehension, survey respondents felt unprepared during their first year of teaching

The Role of Deontic Logic in the Specification of Information Systems

In this paper we discuss the role that deontic logic plays in the specification of information systems, either because constraints on the systems directly concern norms or, and even more importantly, system constraints are considered ideal but violable (so-called `soft¿ constraints).\ud To overcome the traditional problems with deontic logic (the so-called paradoxes), we first state the importance of distinguishing between ought-to-be and ought-to-do constraints and next focus on the most severe paradox, the so-called Chisholm paradox, involving contrary-to-duty norms. We present a multi-modal extension of standard deontic logic (SDL) to represent the ought-to-be version of the Chisholm set properly. For the ought-to-do variant we employ a reduction to dynamic logic, and show how the Chisholm set can be treated adequately in this setting. Finally we discuss a way of integrating both ought-to-be and ought-to-do reasoning, enabling one to draw conclusions from ought-to-be constraints to ought-to-do ones, and show by an example the use(fulness) of this

Ab initio nuclear structure of lithium isotopes with applications of deep learning

We study the ab initio No-Core Shell Model solutions for four Lithium isotopes using a realistic 2-body interaction potential called Daejeon16. This interaction is based on chiral effective field theory and has been softened by a similarity renormalization group evolution in order to provide more rapid convergence of nuclear structure calculations. In addition, Daejeon16 has been treated with phase equivalent transformations adjusted to fit a selection of energy observables for several light nuclei. We use numerical solutions for experimentally observable properties of the Lithium isotopes as input data to train our artificial neural networks. Our networks are trained for eigenenergies, excitation energies, point proton radii, magnetic dipole moments, and electric quadrupole moments. Inputs to the networks are the parameters that define the many-body basis spaces used for the ab-initio calculations: the harmonic oscillator energy spacing $\hbar\omega$ and the many-body basis truncation parameter $N_{\rm max}$. Our neural networks use a predictive algorithm to extrapolate to $N_{\rm max}=70$ and $90$ where good convergence of each observable is expected. After extensive work with Daejeon16 and our developed neural networks, we find reasonable agreement with available experimental results. We also draw comparisons with corresponding results from other ab initio methods and interactions. We note that for most of our studied observables, our results appear to exhibit better agreement with experiment. We also demonstrate some flexibility in training our networks that can be adjusted on a case-by-case basis for each of our isotopes of Lithium