10,199 research outputs found
Extreme Candidates as the Beneficent Spoiler? Range Effect in the Plurality Voting System
How does the entrance of radical candidates influence election results? Conventional wisdom suggests that extreme candidates merely split the votes. Based on the range effect theory in cognitive psychology, we hypothesize that the entrance of an extreme candidate reframes the endpoints of the ideological spectrum among available candidates, which makes the moderate one on the same side to be perceived by the voters as even more moderate. Through two survey experiments in the United States and Taiwan, we provide empirical support for range effect in the vote choice in the plurality system. The results imply that a mainstream party can, even without changing its own manifesto, benefit from the entrance of its radical counterpart; it explains why the mainstream party may choose cooperation strategically. Our findings also challenge the assumption in regression models that the perceived ideological positions of candidates are independent of each other
Ground resonance analysis using a substructure modeling approach
A convenient and versatile procedure for modeling and analyzing ground resonance phenomena is described and illustrated. A computer program is used which dynamically couples differential equations with nonlinear and time dependent coefficients. Each set of differential equations may represent a component such as a rotor, fuselage, landing gear, or a failed damper. Arbitrary combinations of such components may be formulated into a model of a system. When the coupled equations are formed, a procedure is executed which uses a Floquet analysis to determine the stability of the system. Illustrations of the use of the procedures along with the numerical examples are presented
Fresnel transmission coefficients for thermal phonons at solid interfaces
Interfaces play an essential role in phonon-mediated heat conduction in
solids, impacting applications ranging from thermoelectric waste heat recovery
to heat dissipation in electronics. From a microscopic perspective, interfacial
phonon transport is described by transmission and reflection coefficients,
analogous to the well-known Fresnel coefficients for light. However, these
coefficients have never been directly measured, and thermal transport processes
at interfaces remain poorly understood despite considerable effort. Here, we
report the first measurements of the Fresnel transmission coefficients for
thermal phonons at a metal-semiconductor interface using ab-initio phonon
transport modeling and a thermal characterization technique, time-domain
thermoreflectance. Our measurements show that interfaces act as thermal phonon
filters that transmit primarily low frequency phonons, leading to these phonons
being the dominant energy carriers across the interface despite the larger
density of states of high frequency phonons. Our work realizes the
long-standing goal of directly measuring thermal phonon transmission
coefficients and demonstrates a general route to study microscopic processes
governing interfacial heat conduction
Injuries in the Chinese Arena Football League: American Versus Chinese Players.
Background: Arena football is an indoor version of American football played in indoor arenas on a smaller field with 8 players per team. Only 1 study has evaluated injury rates in arena football, and no study had compared 2 distinct cohorts of players.
Purpose/Hypothesis: The purpose of this study was to evaluate and compare injury rates in American versus Chinese athletes in the Chinese Arena Football League. Our hypothesis was that the rate of significant injuries (≥7 days of time lost from play) would be statistically significantly higher in Chinese athletes.
Study Design: Cohort study; Level of evidence, 2.
Methods: Each of the 6 teams included in this study comprised 11 American and 11 Chinese athletes, for a total of 132 included athletes (66 Chinese, 66 American). All players stayed in the same hotel, trained and played in the same facilities, and were covered by the same medical staff. A total of 18 games were played consecutively in 6 cities from October 1 to November 6, 2016. At least 4 Chinese players had to be on the field for each team at all times during game play.
Results: American athletes were significantly older, taller, and heavier than Chinese athletes. The total exposure was 759 athlete-hours, and there were 80 reported injuries, with 74 (92.5%) occurring during games (overall injury rate, 105.4 injuries per 1000 athlete-hours). For American athletes, the exposure was 387 athlete-hours with 38 injuries observed, and the injury rate was 98.2 injuries per 1000 athlete-hours. For Chinese athletes, the exposure was 372 athlete-hours with 42 injuries observed, and the injury rate was 112.9 injuries per 1000 athlete-hours. There was no statistically significant difference in exposure or overall injury rate between American and Chinese athletes. The rate of significant injuries was 30.3 per 1000 athlete-hours; there were 17 such injuries in Chinese athletes compared with 6 such injuries for American athletes. The rate of significant injuries was 45.7 (Chinese) and 15.5 (American) injuries per 1000 athlete-hours, and the relative risk for Chinese versus American athletes for significant injuries was 3.0 (95% CI, 1.2-7.8;
Conclusion: The overall risk of injuries was similar between Chinese and American athletes, but Chinese athletes showed statistically higher rates of significant injuries than their American counterparts. Years of experience was the only factor that was associated with severe injuries. As professional sports become more global, medical personnel must take into account the distinct differences and levels of experience between the national and international professional athletes. The results of this study will be used to make recommendations to develop preventive training measures, including techniques to improve tackling
Temperature Dependent Mean Free Path Spectra of Thermal Phonons Along the c-axis of Graphite
Heat conduction in graphite has been studied for decades because of its
exceptionally large thermal anisotropy. While the bulk thermal conductivities
along the in-plane and cross-plane directions are well known, less understood
are the microscopic properties of the thermal phonons responsible for heat
conduction. In particular, recent experimental and computational works indicate
that the average phonon mean free path (MFP) along the c-axis is considerably
larger than that estimated by kinetic theory, but the distribution of MFPs
remains unknown. Here, we report the first quantitative measurements of c-axis
phonon MFP spectra in graphite at a variety of temperatures using time-domain
thermoreflectance measurements of graphite flakes with variable thickness. Our
results indicate that c-axis phonon MFPs have values of a few hundred
nanometers at room temperature and a much narrower distribution than in
isotropic crystals. At low temperatures, phonon scattering is dominated by
grain boundaries separating crystalline regions of different rotational
orientation. Our study provides important new insights into heat transport and
phonon scattering mechanisms in graphite and other anisotropic van der Waals
solids
SMOOTH BRIGHTNESS TRANSITION FOR COMPUTING DEVICES
A brightness transition module is described that enables a computing device (e.g., a mobile phone, a camera, a tablet computer, etc.) to smoothly adjust an amount of light output by a display of the computing device when the computing device transitions between a high brightness mode and a normal mode (e.g., transitioning based on ambient lighting conditions). By smoothly adjusting the amount of light emitted by the display when transitioning between modes, the brightness transition module may prevent a sudden or abrupt change in the brightness (e.g., prevent a sudden flash when transitioning from the normal mode to the high brightness mode), thereby improving the user experience
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