8,004 research outputs found

    Kinematic Basis of Emergent Energetics of Complex Dynamics

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    Stochastic kinematic description of a complex dynamics is shown to dictate an energetic and thermodynamic structure. An energy function φ(x)\varphi(x) emerges as the limit of the generalized, nonequilibrium free energy of a Markovian dynamics with vanishing fluctuations. In terms of the φ\nabla\varphi and its orthogonal field γ(x)φ\gamma(x)\perp\nabla\varphi, a general vector field b(x)b(x) can be decomposed into D(x)φ+γ-D(x)\nabla\varphi+\gamma, where (ω(x)γ(x))=\nabla\cdot\big(\omega(x)\gamma(x)\big)= ωD(x)φ-\nabla\omega D(x)\nabla\varphi. The matrix D(x)D(x) and scalar ω(x)\omega(x), two additional characteristics to the b(x)b(x) alone, represent the local geometry and density of states intrinsic to the statistical motion in the state space at xx. φ(x)\varphi(x) and ω(x)\omega(x) are interpreted as the emergent energy and degeneracy of the motion, with an energy balance equation dφ(x(t))/dt=γD1γbD1bd\varphi(x(t))/dt=\gamma D^{-1}\gamma-bD^{-1}b, reflecting the geometrical Dφ2+γ2=b2\|D\nabla\varphi\|^2+\|\gamma\|^2=\|b\|^2. The partition function employed in statistical mechanics and J. W. Gibbs' method of ensemble change naturally arise; a fluctuation-dissipation theorem is established via the two leading-order asymptotics of entropy production as ϵ0\epsilon\to 0. The present theory provides a mathematical basis for P. W. Anderson's emergent behavior in the hierarchical structure of complexity science.Comment: 7 page

    Revisiting the problem of audio-based hit song prediction using convolutional neural networks

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    Being able to predict whether a song can be a hit has impor- tant applications in the music industry. Although it is true that the popularity of a song can be greatly affected by exter- nal factors such as social and commercial influences, to which degree audio features computed from musical signals (whom we regard as internal factors) can predict song popularity is an interesting research question on its own. Motivated by the recent success of deep learning techniques, we attempt to ex- tend previous work on hit song prediction by jointly learning the audio features and prediction models using deep learning. Specifically, we experiment with a convolutional neural net- work model that takes the primitive mel-spectrogram as the input for feature learning, a more advanced JYnet model that uses an external song dataset for supervised pre-training and auto-tagging, and the combination of these two models. We also consider the inception model to characterize audio infor- mation in different scales. Our experiments suggest that deep structures are indeed more accurate than shallow structures in predicting the popularity of either Chinese or Western Pop songs in Taiwan. We also use the tags predicted by JYnet to gain insights into the result of different models.Comment: To appear in the proceedings of 2017 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP

    Two distinct topological phases in the mixed valence compound YbB6 and its differences from SmB6

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    We discuss the evolution of topological states and their orbital textures in the mixed valence compounds SmB6 and YbB6 within the framework of the generalized gradient approximation plus onsite Coulomb interaction (GGA+U) scheme for a wide range of values of U. In SmB6, the topological Kondo insulator (TKI) gap is found to be insensitive to the value of U, but in sharp contrast, Kondo physics in isostructural YbB6 displays a surprising sensitivity to U. In particular, as U is increased in YbB6, the correlated TKI state in the weak-coupling regime transforms into a d-p-type topological insulator phase with a band inversion between Yb-5d and B-2p orbitals in the intermediate coupling range, without closing the insulating energy gap throughout this process. Our theoretical predictions related to the TKI and non-TKI phases in SmB6 and YbB6 are in substantial accord with recent angle-resolved photoemission spectroscopy (ARPES) experiments.Comment: 6 pages, 4 figures URL: http://link.aps.org/doi/10.1103/PhysRevB.91.15515

    Efficacy of purchasing activities and strategic involvement: an international comparison

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    The purchasing function plays a strategic role in a company’s ability to compete. As globalization continues to increase, what becomes interesting is the effect that national culture may have on purchasing activities and, ultimately, manufacturing competitiveness. This study examines the effects of purchasing activities and the purchasing function’s involvement with corporate strategy on manufacturing competitiveness as it is affected by national differences. In particular, we are interested in the research question: Do purchasing theories built on samples from mainly North American and Western European countries apply in other countries with different cultural contexts? The statistical results provide evidence that the engagement and efficacy of purchasing activities and strategic involvement within companies vary by national culture. Moreover, a particular cultural dimension, Long-term orientation, is significantly related to the efficacy of purchasing activities and strategic involvement. This finding has important implications from the perspective of purchasing decision-making in global operations. Specifically, top managers from different nations could adopt and implement similar purchasing activities, but those activities could lead to different outcomes depending on the culture. The paper concludes by reviewing research limitations and suggests further examination of operations management theories

    Elderly Patients with Laryngeal and Hypopharyngeal Cancer Undergoing Total Pharyngolaryngectomy with a Radial Forearm, Free Flap-reconstructed Phonation Tube

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    SummaryBackgroundThe radial forearm, free-flap (RFFF)-reconstructed phonation tube was developed for functional restoration of voice after total pharyngolaryngectomy. We aimed to report the efficacy of RFFF phonation tube after pharyngolaryngectomy with radiotherapy (RT) or concurrent chemoradiation therapy (CCRT) with intensity-modulated radiotherapy (IMRT) for elderly.Materials and methodsTen patients with laryngeal and hypopharyngeal cancer underwent total pharyngolaryngectomy and one-stage reconstruction with an RFFF-accompanied phonation tube, followed by RT or CCRT. Voice restoration was achieved with the RFFF-reconstructed phonation tube. Functional outcomes of phonation and speech were evaluated and scored.ResultsPercentages of stage III and stage IV patients among all participants were 10% and 90%, respectively. The median follow-up time was 31 months (range, 4–67 months). Almost 9 out of 10 (90%) patients experienced phonation efficacy greater than 80%. The maximal phonation time per breath was 70% longer than 3 sec. The graded as mild of wet voice was 90%. Percentage of mild decreased loudness was 60% and that of low and high pitch was 80%. Of the 10 patients, 40% could count more than 10 and 70% could pronounce more than 1 to 5 words per breath. After RT or CCRT, of patients had moderately good to excellent speech intelligibility.ConclusionThe RFFF phonation tube that was used after pharyngolaryngectomy with RT or CCRT with IMRT provided acceptable complications and functional restoration of voice for elderly patients

    High-Efficiency Isolated Photovoltaic Microinverter Using Wide-Band Gap Switches for Standalone and Grid-Tied Applications

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    An isolated photovoltaic micro-inverter for standalone and grid-tied applications is designed and implemented to achieve high efficiency. System configuration and design considerations, including the proposed active-clamp forward-flyback resonant converter for the DC-DC stage and a dual-frequency full-bridge inverter for the DC-AC stage, are analyzed and discussed. A prototype microinverter system is built and tested. Experimental results verify the feasibility of the proposed system, which achieves 95% power conversion efficiency at full load

    Application of the SUSTAIN Model to a Watershed-Scale Case for Water Quality Management

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    [[abstract]]Low impact development (LID) is a relatively new concept in land use management that aims to maintain hydrological conditions at a predevelopment level without deteriorating water quality during land development. The United States Environmental Protection Agency (USEPA) developed the System for Urban Stormwater Treatment and Analysis Integration model (SUSTAIN) to evaluate the performance of LID practices at different spatial scales; however, the application of this model has been limited relative to LID modeling. In this study, the SUSTAIN model was applied to a Taiwanese watershed. Model calibration and verification were performed, and different types of LID facilities were evaluated. The model simulation process and the verified model parameters could be used in other cases. Four LID scenarios combining bioretention ponds, grass swales, and pervious pavements were designed based on the land characteristics. For the SUSTAIN model simulation, the results showed that pollution reduction was mainly due to water quantity reduction, infiltration was the dominant mechanism and plant interception had a minor effect on the treatment. The simulation results were used to rank the primary areas for nonpoint source pollution and identify effective LID practices. In addition to the case study, a sensitivity analysis of the model parameters was performed, showing that the soil infiltration rate was the most sensitive parameter affecting the LID performance. The objectives of the study are to confirm the applicability of the SUSTAIN model and to assess the effectiveness of LID practices in the studied watershed.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]電子
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