5,967 research outputs found
Hawking-like emission in kink-soliton escape from a potential well.
The escape of solitons over a potential barrier is analysed within the framework of a nonlinear Klein–Gordon equation. It is shown that the creation of a kink–antikink pair near the barrier through an internal mode instability can be followed by escape of the kink in a process analogous to Hawking radiation. These results have important implications in a wider context, including stochastic resonance and ratchet systems, which are also discussed
Latino Electoral and Nonelectoral Political Participation: Findings from the 1996 Chicago Latino Registered Voter Survey
The Latino population in the United States has been expanding at a tremendous rate in recent decades and as the number of Latinos in the United States grows, so does their potential for influencing American politics grow. Yet, we have a very limited understanding of Latino civic engagement, political behavior, and public policy opinions. This article presents the results of a survey of 408 registered Latino voters in Chicago, Illinois. The findings advance a multidimensional understanding of Latino political behaviors and attitudes through the examination of multiple measures of political participation and opinions concerning political parties and public issues such as welfare reform, immigration, naturalization and official language policy, bilingual education, capital punishment, gun control, and affirmative action. Findings are discussed in the context of earlier studies of Latino electoral participation and American public policy opinions
Characterizing the variation of propagation constants in multicore fibre
We demonstrate a numerical technique that can evaluate the core-to-core
variations in propagation constant in multicore fibre. Using a Markov Chain
Monte Carlo process, we replicate the interference patterns of light that has
coupled between the cores during propagation. We describe the algorithm and
verify its operation by successfully reconstructing target propagation
constants in a fictional fibre. Then we carry out a reconstruction of the
propagation constants in a real fibre containing 37 single-mode cores. We find
that the range of fractional propagation constant variation across the cores is
approximately .Comment: 17 pages; preprint format; 5 figures. Submitted to Optics Expres
Resonant electron transmission through a finite quantum spin chain
Electron transport in a finite one dimensional quantum spin chain (with
ferromagnetic exchange) is studied within an exchange Hamiltonian. Spin
transfer coefficients strongly depend on the sign of the exchange
constant. For a ferromagnetic coupling, they exhibit a novel resonant pattern,
reflecting the salient features of the combined electron-spin system. Spin-flip
processes are inelastic and feasible at finite voltage or at finite
temperature.Comment: 4 pages including 4 .eps figure
Thermoelectric Figure of Merit of Strongly Correlated Superlattice Semiconductors
We solved the Anderson Lattice Hamiltonian to get the energy bands of a
strongly correlated semiconductor by using slave boson mean field theory. The
transport properties were calculated in the relaxation-time approximation,and
the thermoelectric figure of merit was obtained for the strongly correlated
semiconductor and its superlattice structures. We found that at room
temperature can reach nearly 2 for the quantum wire lattice structure.We
believe that it is possible to find high values of thermoelectric figure of
merit from strongly correlated semiconductor superlattice systems.Comment: 4 pages, 3 figure
Improving Navy MPTE Studies with Model-Driven Big Data
The goal of this research was to improve upon the ability of OPNAV N1 analysts to quickly and efficiently obtain experiment-based information from their computational models. The enhanced information will enable N1’s analysts to better support Navy leadership in resource and policy decisions that shape the future Navy and help it retain and develop its most talented Sailors. This project built on previous collaborations with N1 using data farming to enhance the information gleaned from their Navy talent management models, such as the Officer Strategic Analysis Model (OSAM) model, the Production Resource Optimization (PRO) model, and the Navy Total Force Strength Model (NTFSM). During this research period, (1) Ensign William Desousa (2015) investigated the behavior of economic inputs in NTFSM; (2) Lieutenant Peter Bazalaki (2016) used the new data farming capabilities we developed in OSAM to investigate Surface Warfare Officer (SWO) inventory across a breadth of possibilities; and (3) Lieutenant Allison Hogarth (2016) built, tested, and demonstrated a user interface in Excel that enables users of the PRO model to automatically execute a sophisticated design of experiments—the tool that enables this new capability is known as Production Resource Optimization Model With Experimental Design (PROMWED). In addition to working with the student-officers, the faculty supporting this project performed an empirical study of statistical software packages that may provide better understanding of the high-dimensional behavior of manpower models in the future (Erickson, Ankenman, & Sanchez 2016).Naval Research ProgramPrepared for Topic Sponsor: OPNAV N1; Research POC Name: Mr. Ian AndersoNPS-N16-N154-
Gender, competition and performance: evidence from chess players
This paper studies gender differences in performance in a male‐dominated competitive environment chess tournaments. We find that the gender composition of chess games affects the behaviors of both men and women in ways that worsen the outcomes for women. Using a unique measure of within‐game quality of play, we show that women make more mistakes when playing against men. Men, however, play equally well against male and female opponents. We also find that men persist longer before losing to women. Our results shed some light on the behavioral changes that lead to differential outcomes when the gender composition of competitions varies
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