10,360 research outputs found

    A new mechanism for a naturally small Dirac neutrino mass

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    A mechanism is proposed in which a right-handed neutrino zero mode and a right-handed charged lepton zero mode can be localized at the same place along an extra compact dimension while having markedly different spreads in their wave functions: a relatively narrow one for the neutrino and a rather broad one for the charged lepton. In their overlaps with the wave function for the left-handed zero modes, this mechanism could produce a natural large hierarchy in the effective Yukawa couplings in four dimensions, and hence a large disparity in masses.Comment: 6 pages (2 with figures), twocolumn forma

    PCA-SIR: a new nonlinear supervised dimension reduction method with application to pain prediction from EEG

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    Dimension reduction is critical in identifying a small set of discriminative features that are predictive of behavior or cognition from high-dimensional neuroimaging data, such as EEG and fMRI. In the present study, we proposed a novel nonlinear supervised dimension reduction technique, named PCA-SIR (Principal Component Analysis and Sliced Inverse Regression), for analyzing high-dimensional EEG time-course data. Compared with conventional dimension reduction methods used for EEG, such as PCA and partial least-squares (PLS), the PCA-SIR method can make use of nonlinear relationship between class labels (i.e., behavioral or cognitive parameters) and predictors (i.e., EEG samples) to achieve the effective dimension reduction (e.d.r.) directions. We applied the new PCA-SIR method to predict the subjective pain perception (at a level ranging from 0 to 10) from single-trial laser-evoked EEG time courses. Experimental results on 96 subjects showed that reduced features by PCA-SIR can lead to significantly higher prediction accuracy than those by PCA and PLS. Therefore, PCA-SIR could be a promising supervised dimension reduction technique for multivariate pattern analysis of high-dimensional neuroimaging data. © 2015 IEEE.published_or_final_versio

    Single-trial detection of visual evoked potentials by common spatial patterns and wavelet filtering for brain-computer interface

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    Event-related potentials (ERPs) are widely used in brain-computer interface (BCI) systems as input signals conveying a subject's intention. A fast and reliable single-trial ERP detection method can be used to develop a BCI system with both high speed and high accuracy. However, most of single-trial ERP detection methods are developed for offline EEG analysis and thus have a high computational complexity and need manual operations. Therefore, they are not applicable to practical BCI systems, which require a low-complexity and automatic ERP detection method. This work presents a joint spatial-time-frequency filter that combines common spatial patterns (CSP) and wavelet filtering (WF) for improving the signal-to-noise (SNR) of visual evoked potentials (VEP), which can lead to a single-trial ERP-based BCI.published_or_final_versio

    A Novel IoT Based Positioning and Shadowing System for Dementia Training.

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    A rapid increase in the number of patients with dementia, particularly memory decline or impairment, has led to the loss of self-care ability in more individuals and increases in medical and social costs. Numerous studies, and clinical service experience, have revealed that the intervention of nonpharmacological management for people with dementia is effective in delaying the degeneration caused by dementia. Due to recent rapid developments in information and communications technology, many innovative research and development and cross-domain applications have been effectively used in the dementia care environment. This study proposed a new short-term memory support and cognitive training application technology, a "positioning and shadowing system," to delay short-term memory degeneration in dementia. Training courses that integrate physical and digital technologies for the indoor location of patients with dementia were constructed using technologies such as Bluetooth Low Energy, fingerprint location algorithm, and short-range wireless communication. The Internet of Things was effectively applied to a clinical training environment for short-term memory. A pilot test verified that the results demonstrated learning effects in cognitive training and that the system can assist medical personnel in training and nursing work. Participants responded with favorable feedback regarding course satisfaction and system usability. This study can be used as a reference for future digital smart cognitive training that allows observation of the performance of patients with dementia in activities of daily living

    A Study on Tourism Development Strategy of Kaohsiung City in Taiwan after Urban Style Regeneration

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    Urban tourism has gradually been emphasized in past years; especially, it is regarded as a savior of urban regeneration in old industrial cities. When losing the competitive advantages and getting declined, old industrial cities are facing the challenge of transformation. The development of urban tourism is considered as the opportunity of industrial cities in dark recession that they start to involve in the development of tourism. Analytic Hierarchy Process (AHP) is applied in this study to evaluate key success factors in the tourism development strategy of Kaohsiung City after the urban style regeneration. AHP is used for confirming the levels of various evaluation factors. The first hierarchy contains four evaluation dimensions, and 14 evaluation standards are covered in the second hierarchy. The results reveal the important sequence of four evaluation factors in the second hierarchy as (1) marketing activity, (2) management strategy, (3) recreational environment, and (4) infrastructure, where the importance of evaluation factors in the third hierarchy is sequenced as (1) urban attraction, (2) environmental facility maintenance, (3) celebrations, (4) local characteristics, and (5) natural landscape. The research results and suggestions in this study are expected to enhance the tourism development of Kaohsiung City in Taiwan after the urban style regeneration.     Keywords: urban style, tourism development strategy, key success factors, Delphi method, AH

    Kaluza-Klein Structure Associated With Fat Brane

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    It is known that the imposition of orbifold boundary conditions on background scalar field can give rise to a non-trivial vacuum expectation value (VEV) along extra dimensions, which in turn generates fat branes and associated unconventional Kaluza-Klein (KK) towers of fermions. We study the structure of these KK towers in the limit of one large extra dimension and show that normalizable (bound) states of massless and massive fermions can exist at both orbifold fixed points. Closer look however indicates that orbifold boundary conditions act to suppress at least half of bound KK modes, while periodic boundary conditions tend to drive the high-lying modes to the conventional structure. By investigating the scattering of fermions on branes, we analytically compute masses and wavefunctions of KK spectra in the presence of these boundary conditions up to one-loop level. Implication of KK-number non-conservation couplings on the Coulomb potential is also examined.Comment: RevTex4, 29 pages, 7 ps figures, new references adde

    Vector-pseudoscalar two-meson distribution amplitudes in three-body BB meson decays

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    We study three-body nonleptonic decays BVVPB\to VVP by introducing two-meson distribution amplitudes for the vector-pseudoscalar pair, such that the analysis is simplified into the one for two-body decays. The twist-2 and twist-3 ϕK\phi K two-meson distribution amplitudes, associated with longitudinally and transversely polarized ϕ\phi mesons, are constrained by the experimental data of the τϕKν\tau\to\phi K\nu and BϕKγB\to\phi K\gamma branching ratios. We then predict the BϕKγB\to\phi K\gamma and BϕϕKB\to\phi\phi K decay spectra in the ϕK\phi K invariant mass. Since the resonant contribution in the ϕK\phi K channel is negligible, the above decay spectra provide a clean test for the application of two-meson distribution amplitudes to three-body BB meson decays.Comment: 9 pages, 1 figure, Revtex4, version to appear in PR

    Threshold pi^0 photo- and electro-production in a meson-exchange model

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    We show that, within a meson-exchange dynamical model describing well most of the existing pion electromagnetic production data up to the second resonance region, one is also able to obtain a good agreement with the pi^0 photo- and electroproduction data near threshold. In the case of pi^0 production, the effects of final state interaction in the threshold region are nearly saturated by single charge exchange rescattering. This indicates that in ChPT, it might be sufficient to carry out the calculation just up to one-loop diagrams for threshold neutral pion production.Comment: 6 pages LATEX including 1 tables and 4 figures, uses espcrc1.st
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