113 research outputs found
Odd Sensation Induced by Moving-Phantom which Triggers Subconscious Motor Program
Our motor actions are sometimes not properly performed despite our having complete understanding of the environmental situation with a suitable action intention. In most cases, insufficient skill for motor control can explain the improper performance. A notable exception is the action of stepping onto a stopped escalator, which causes clumsy movements accompanied by an odd sensation. Previous studies have examined short-term sensorimotor adaptations to treadmills and moving sleds, but the relationship between the odd sensation and behavioral properties in a real stopped-escalator situation has never been examined. Understanding this unique action-perception linkage would help us to assess the brain function connecting automatic motor controls and the conscious awareness of action.
Here we directly pose a question: Does the odd sensation emerge because of the unfamiliar motor behavior itself toward the irregular step-height of a stopped escalator or as a consequence of an automatic habitual motor program cued by the escalator itself. We compared the properties of motor behavior toward a stopped escalator (SE) with those toward moving escalator and toward a wooden stairs (WS) that mimicked the stopped escalator, and analyzed the subjective feeling of the odd sensation in the SE and WS conditions. The results show that moving escalator-specific motor actions emerged after participants had stepped onto the stopped escalator despite their full awareness that it was stopped, as if the motor behavior was guided by a âphantomâ of a moving escalator. Additionally, statistical analysis reveals that postural forward sway that occurred after the stepping action is directly linked with the odd sensation.
The results suggest a dissociation between conscious awareness and subconscious motor control: the former makes us perfectly aware of the current environmental situation, but the latter automatically emerges as a result of highly habituated visual input no matter how unsuitable the motor control is. This dissociation appears to yield an attribution conflict, resulting in the odd sensation
Resonant Spin-Flavor Conversion of Supernova Neutrinos: Dependence on Electron Mole Fraction
Detailed dependence of resonant spin-flavor (RSF) conversion of supernova
neutrinos on electron mole fraction Ye is investigated. Supernova explosion
forms a hot-bubble and neutrino-driven wind region of which electron mole
fraction exceeds 0.5 in several seconds after the core collapse. When a higher
resonance of the RSF conversion is located in the innermost region, flavor
change of the neutrinos strongly depends on the sign of 1-2Ye. At an adiabatic
high RSF resonance the flavor conversion of bar{nu}_e -> nu_{mu,tau} occurs in
Ye 0.5 and inverted mass hierarchy.
In other cases of Ye values and mass hierarchies, the conversion of nu_e ->
bar{nu}_{mu,tau} occurs. The final bar{nu}_e spectrum is evaluated in the cases
of Ye 0.5 taking account of the RSF conversion. Based on the
obtained result, time variation of the event number ratios of low bar{nu}_e
energy to high bar{nu}_e energy is discussed. In normal mass hierarchy, an
enhancement of the event ratio should be seen in the period when the electron
fraction in the innermost region exceeds 0.5. In inverted mass hierarchy, on
the other hand, a dip of the event ratio should be observed. Therefore, the
time variation of the event number ratio is useful to investigate the effect of
the RSF conversion.Comment: 16 pages, 33 figures, accepted for publication in Physical Review
INTER-TRIAL DIFFERENCE ANALYSIS THROUGH APPEARANCE-BASED MOTION TRACKING
The purpose of this study is to develop a method for quantitative evaluation and visualization of inter-trial differences in the motion of athletes. Previous methods for kinematic analyses of human movement have required attaching specific equipment to a body segment or can only be used in an environment designed for analyses. Therefore, they are difficult to use for observing motions in real games. To enhance the applicability to real-game situations, we propose appearance-based motion tracking. Our method only requires an image sequence from a camera. From the image sequence, automatic detection of trials and a difference analysis of them are conducted. We applied our method to the analysis of pitching motions in actual baseball games. Though we have no quantitative evaluations yet, the experimental results imply the efficacy of our method
Odd Sensation Induced by Moving-Phantom which Triggers Subconscious Motor Program
Our motor actions are sometimes not properly performed despite our having complete understanding of the environmental situation with a suitable action intention. In most cases, insufficient skill for motor control can explain the improper performance. A notable exception is the action of stepping onto a stopped escalator, which causes clumsy movements accompanied by an odd sensation. Previous studies have examined short-term sensorimotor adaptations to treadmills and moving sleds, but the relationship between the odd sensation and behavioral properties in a real stopped-escalator situation has never been examined. Understanding this unique action-perception linkage would help us to assess the brain function connecting automatic motor controls and the conscious awareness of action.
Here we directly pose a question: Does the odd sensation emerge because of the unfamiliar motor behavior itself toward the irregular step-height of a stopped escalator or as a consequence of an automatic habitual motor program cued by the escalator itself. We compared the properties of motor behavior toward a stopped escalator (SE) with those toward moving escalator and toward a wooden stairs (WS) that mimicked the stopped escalator, and analyzed the subjective feeling of the odd sensation in the SE and WS conditions. The results show that moving escalator-specific motor actions emerged after participants had stepped onto the stopped escalator despite their full awareness that it was stopped, as if the motor behavior was guided by a âphantomâ of a moving escalator. Additionally, statistical analysis reveals that postural forward sway that occurred after the stepping action is directly linked with the odd sensation.
The results suggest a dissociation between conscious awareness and subconscious motor control: the former makes us perfectly aware of the current environmental situation, but the latter automatically emerges as a result of highly habituated visual input no matter how unsuitable the motor control is. This dissociation appears to yield an attribution conflict, resulting in the odd sensation
Supernova Neutrino Nucleosynthesis of Light Elements with Neutrino Oscillations
Light element synthesis in supernovae through neutrino-nucleus interactions, i.e., the Îœ-process, is aïŹected by neutrino oscillations in the supernova environment. There is a resonance of 13-mixing in the O/C layer, which increases the rates of charged-current Îœ-process reactions in the outer He-rich layer. The yields of 7Li and 11B increase by about a factor of 1.9 and 1.3, respectively, for a normal mass hierarchy and an adiabatic 13-mixing resonance, compared to those without neutrino oscillations. In the case of an inverted mass hierarchy and a non-adiabatic 13-mixing resonance, the increase in the 7Li and 11B yields is much smaller. Observations of the 7Li/11B ratio in stars showing signs of supernova enrichment could thus provide a unique test of neutrino oscillations and constrain their parameters and the mass hierarchy
Reflections in gyrotrons with axial output
Influence of reflections on operation of gyrotrons with axial output is studied both theoretically and experimentally. By way of example the Fukui large orbit gyrotron with a permanent magnet operating in third harmonic at frequency 89 GHz is considered. In the case of strong reflection (|R|=0.6), extreme sensitivity of output power on the reflection phase is found. A qualitative agreement between theory and experiment is observed
Supernova Neutrino Nucleosynthesis of Light Elements with Neutrino Oscillations
Light element synthesis in supernovae through neutrino-nucleus interactions,
i.e., the nu-process, is affected by neutrino oscillations in the supernova
environment. There is a resonance of 13-mixing in the O/C layer, which
increases the rates of charged-current nu-process reactions in the outer
He-rich layer. The yields of 7Li and 11B increase by about a factor of 1.9 and
1.3, respectively, for a normal mass hierarchy and an adiabatic 13-mixing
resonance, compared to those without neutrino oscillations. In the case of an
inverted mass hierarchy and a non-adiabatic 13-mixing resonance, the increase
in the 7Li and 11B yields is much smaller. Observations of the 7Li/11B ratio in
stars showing signs of supernova enrichment could thus provide a unique test of
neutrino oscillations and constrain their parameters and the mass hierarchy.Comment: 5 pages, 3 figures, accepted for publication in Physical Review
Letter
Neutrino-Nucleus Reaction Cross Sections for Light Element Systhesis in Supernova Explosions
The neutrino-nucleus reaction cross sections of 4He and 12C are evaluated using new shell model Hamiltoni-ans. Branching ratios of various decay channels are calculated to evaluate the yields of Li, Be, and B producedthrough the Îœ -process in supernova explosions. The new cross sections enhance the yields of7Li and11B pro-duced during the supernova explosion of a 16.2 Mâstar model compared to the case using the conventionalcross sections by about 10%. On the other hand, the yield of10B decreases by a factor of two. The yieldsof6Li,9Be, and the radioactive nucleus10 Be are found at a level of ⌠10â11Mâ. The temperature of Μ”,Ï-and ÂŻÎœÂ”,Ï-neutrinos inferred from the supernova contribution of11B in Galactic chemical evolution models isconstrained to the 4.3 â 6.5 MeV range. The increase in the7Li and11B yields due to neutrino oscillations isdemonstrated with the new cross section
Neutrino-Nucleus Reaction Cross Sections for Light Element Synthesis in Supernova Explosions
The neutrino-nucleus reaction cross sections of 4He and 12C are evaluated
using new shell model Hamiltonians. Branching ratios of various decay channels
are calculated to evaluate the yields of Li, Be, and B produced through the
nu-process in supernova explosions. The new cross sections enhance the yields
of 7Li and 11B produced during the supernova explosion of a 16.2 M_odot star
model compared to the case using the conventional cross sections by about 10%.
On the other hand, the yield of 10B decreases by a factor of two. The yields of
6Li, 9Be, and the radioactive nucleus 10Be are found at a level of 10^{-11}
M_odot. The temperature of nu_{mu,tau}- and bar{nu}_{mu,tau}-neutrinos inferred
from the supernova contribution of 11B in Galactic chemical evolution models is
constrained to the 4.3-6.5 MeV range. The increase in the 7Li and 11B yields
due to neutrino oscillations is demonstrated with the new cross sections.Comment: 19 pages, 30 figures, accepted for publication in Astrophysical
Journal. Typos are correcte
Neutrino Oscillation Effects on Supernova Light Element Synthesis
Neutrino oscillations affect light element synthesis through the
neutrino-process in supernova explosions. The 7Li and 11B yields produced in a
supernova explosion of a 16.2 solar-mass star model increase by factors of 1.9
and 1.3 in the case of large mixing angle solution with normal mass hierarchy
and sin^{2}2theta_{13} > 0.002 compared with those without the oscillations. In
the case of inverted mass hierarchy or nonadiabatic 13-mixing resonance, the
increment of their yields is much smaller. Neutrino oscillations raise the
reaction rates of charged-current neutrino-process reactions in the region
outside oxygen-rich layers. The number ratio of 7Li/11B could be a tracer of
normal mass hierarchy and relatively large theta_{13}, still satisfying
sin^{2}2theta_{13} < 0.1, through future precise observations in stars having
strong supernova component.Comment: 35 pages, 17 figures, accepted for publication in Astrophysical
Journa
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