The study focuses on the average energy of a monolayer of granular particles confined in a rectangular container. The container is shaken sinusoidally in a horizontal plane. The motion of every particle is recorded by a CCD camera so that the kinetic energy of the system can be analyzed by tracking the trajectory of each particle. It is found that the average energy changes abruptly at a certain critical filling fraction while the configuration of the particles makes a transition from a disordered to a solid-like state. We determine the critical value of the filling fraction and the energy of the solid-like state using a resonant condition
The aim of this study was to apply frequency bands to explore how mental rotation strategies affect the identification of 2D figures. Eighteen adults were recruited for this study. In the ERP experiments, the participants were required to identify 2D figures with mental rotation. The results showed the differences between the high-achieving (HA) and low-achieving (LA) spatial ability participants in their use of mental rotation for identifying 2D figures. At 300-380 ms, the HA participants showed higher brain activity in the right hemisphere than in other brain areas, whereas the LA participants showed activity in the whole brain. At 520 to 620 ms, the areas of brain activity were in the opposite hemisphere for the HA and LA participants. The highest brain activity was shown in the left hemisphere of the HA participants and in the right hemisphere for the LA participants at 520 to 620 ms. The implication of this study is that right hemisphere specialization for mental rotation might appear in early cognitive processing, but in late cognitive processing, the left hemisphere specialization form of mental rotation might show an advantage.
The eigenvalue problem approach to the blind source separation ͓L. Molgedey and H. G. Schuster, Phys. Rev. Lett. 72, 3634 ͑1994͔͒ is reinvestigated. The essential assumption is that the source signals should be statistically independent for the eigenvalue method to be applicable. When the source signals are correlated, unfortunately, this elegant approach faces a serious problem of optimization. We propose that by employing a reference signal in the separation procedure, the reconstructed signals that have an optimum minimum mismatch to the original sources can be obtained. The role and the criterion in choosing the reference signal will be extensively illustrated. Furthermore, the influences of nonzero correlation between different source signals, finite data length, and channel noises on signal separation will also be fully clarified.
Auditory phase-synchronization near 40Hz is reportedly related to sensory stimulation. This study applied the phase synchrony analysis and Bi-coherence analyses to analyze the electroencephalographic measurements. Four experimental stages were conducted with 34 healthy high school students to collect the data: (A) resting with eyes closed, (B) listening to the classical music, (C) resting with eyes closed, and (D) listening to popular music. The result shows that the whole brain phase-synchronization occurs at 40Hz and lasts about 400 ms, which is quite different from the estimated 40Hz phase-coupling lasting about 20–25 ms in previous studies and seems to play an important role in inducing auditory attention loss. Additionally, the result also shows that hypersynchronous states may affect perceptual processing. This study develops an original nonlinear time serial analytical approach and suggests that 40Hz phase-synchronization might be an important indicator in perceptual process.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.