Unsteady effects of a control surface in two dimensional subsonic and transonic flow

The experimental results of steady and unsteady pressure measurements, carried out in subsonic and transonic flow on a 16 percent relative thickness supercritical aerofoil, equipped with a trailing edge flap involving 25 percent of the chord, in a sinusoidal motion are given. These experimental results are compared with those obtained by various methods of steady and unsteady inviscid flow calculations. Some calculation results in which viscous effects have been taken into account, for both steady and unsteady flows, are also presented

Response in kinetic Ising model to oscillating magnetic fields

Ising models obeying Glauber dynamics in a temporally oscillating magnetic field are analyzed. In the context of stochastic resonance, the response in the magnetization is calculated by means of both a mean-field theory with linear-response approximation, and the time-dependent Ginzburg-Landau equation. Analytic results for the temperature and frequency dependent response, including the resonance temperature, compare favorably with simulation data.Comment: RevTex, 6 pages, two-column, 2 figure

Capillary Waves at Liquid/Vapor Interfaces: A Molecular Dynamics Simulation

Evidence for capillary waves at a liquid/vapor interface are presented from extensive molecular dynamics simulations of a system containing up to 1.24 million Lennard-Jones particles. Careful measurements show that the total interfacial width depends logarithmically on $L_\parallel$, the length of the simulation cell parallel to the interface, as predicted theoretically. The strength of the divergence of the interfacial width on $L_\parallel$ depends inversely on the surface tension $\gamma$. This allows us to measure $\gamma$ two ways since $\gamma$ can also be obtained from the difference in the pressure parallel and perpendicular to the interface. These two independent measures of $\gamma$ agree provided that the interfacial order parameter profile is fit to an error function and not a hyperbolic tangent, as often assumed. We explore why these two common fitting functions give different results for $\gamma$

Andragogy for All? A Look at Arkansas Community College Students\u27 Preferences for Andragogical Assumptions

Community colleges are tasked with juggling multiple missions. They provide open access to education for adults in their community, work with industry partners to educate the local workforce, and provide relevant programming to the communities they serve. When compared with students at four-year institutions, community college students are older, more ethnically and racially diverse, come from lower socioeconomic statuses, and less academically prepared. Like other community colleges across the country, one of the primary goals of Arkansas community colleges is to help their students succeed. Unfortunately, the state has historically performed poorly in regard to educational outcomes. To get the state back on track, Governor Hutchison enacted a law that moved institutions of higher education to a performance-based model. While student success has always been a concern, beginning in the 2018 academic year, it also became a measure that directly impacts Arkansas higher education institutions funding. Now, more than ever, it is essential for these institutions to understand what is needed to help students succeed. Matching teaching strategies to student learning preferences is one way to ensure student success. According to the Organization for Economic Cooperation and Development (OECD), “Learning strategies may affect individuals’ ability to learn” (2011b, p.5), and research has shown that accounting for learners’ preferences affects learning performance (Jones et al., 2019; Onder & Silay, 2016; Roessger, 2013). With a better understanding of students’ learning preferences, educators and administrators can make more informed decisions on what learning strategies and approaches to use. Andragogy has been a widely accepted model for teaching adult learners, though many criticisms exist surrounding the learning method’s relevance. Some argue that andragogical assumptions fail to consider issues of gender (Sandlin, 2005), race/ethnicity (Duff, 2019), other social contexts like socioeconomic status and culture (Hansman & Mott, 2010; Lee, 2003; Sandlin, 2005). Others cite a lack of empirical evidence as the reason for their criticism (Merriam et al., 2007; Taylor & Kroth, 2009). A recent study conducted by Roessger et al. (2020) gives credence to all of these concerns, as they found that on an international level, preference for andragogical assumptions varies based on age, gender, education level, occupational skill level, culture, country of origin, and ability of the country to meet basic needs. This study used multiple linear regression to investigate the relationship between student preferences for andragogical assumptions and their age, race/ethnicity, gender, socioeconomic status, college readiness, class standing, program type, and culture. It also investigated whether age influences the relationship between gender and preference for andragogical assumptions. Significant relationships were found between preference and gender and preference and race/ethnicity. No significant relationship was found among the remaining variables. Even with the significant findings, it appears preference for andragogical assumptions among Arkansas community college students is high. As such, educators at these institutions should consider employing andragogical methods in their classrooms. Future research should continue to focus on how individual student characteristics relate to learning preferences

A Lifeʼs Worth: Reexamining \u3cem\u3eWergild\u3c/em\u3e in the Anglo-Saxon Royal Law Codes (c. 600-1035)

In the wide and growing world of Anglo-Saxon scholarship, wergild has an at once ubiquitous and spectral presence.1 While compensation, blood-money, and the place of the body in “barbarian” law more generally continue to be subjects of much scholarly interest, it is harder to find even a single piece of scholarship dedicated to the topic, let alone specifically as it appears in the Old English material.2 What follows is meant to offer a survey of wergild as it appears in the surviving legislation of England’s Anglo-Saxon kings, as well as an attempt to deconstruct the logical underpinning of wergild, with the goal finally of tying these various aspects together in order to reach a more nuanced definition for this concept as it exists within these texts and the legislative imaginations of their compilers. Rather than seeing wergild as representing a number of different forms of payment linked together only by the name and sums involved, it is intuitively more likely that the compound represents a more limited and exact concept which could be used, rationally, as we find it in these law codes. This search has so far yielded three major points about the inner workings of wergild: that it is an essentially unchanging part of Old English legal vocabulary and so probably a true reflection of Anglo-Saxon customary law, that it functions as an alternative to loss in a highly general sense, and, more tenuously, that it is calculated based on an individual’s role in preserving the public peace (frið)

Hysteresis loop areas in kinetic Ising models: Effects of the switching mechanism

Experiments on ferromagnetic thin films have measured the dependence of the hysteresis loop area on the amplitude and frequency of the external field, $A$=$A(H_{0},\omega)$, and approximate agreement with numerical simulations of Ising models has been reported. Here we present numerical and theoretical calculations of $A$ in the low-frequency regime for two values of $H_{0}$, which bracket a temperature and system-size dependent crossover field. Our previous Monte Carlo studies have shown that the hysteretic response of the kinetic Ising model is qualitatively different for amplitudes above and below this crossover field. Using droplet theory, we derive analytic expressions for the low-frequency asymptotic behavior of the hysteresis loop area. In both field regimes, the loop area exhibits an extremely slow approach to an asymptotic, logarithmic frequency dependence of the form $A \propto - [\ln (H_{0} \omega)]^{-1}$. Our results are relevant to the interpretation of data from experiments and simulations, on the basis of which power-law exponents for the hysteresis-loop area have been reported.Comment: 9 pages including 3 figures. Submitted as a manuscript for the 7th Joint MMM-Intermag conference. To be published in the Journal of Applied Physics and the IEEE Transactions on Magnetics. Contains 1 updated figure and revised tex