3,321 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=γD−1γ−bD−1bd\varphi(x(t))/dt=\gamma D^{-1}\gamma-bD^{-1}b, reflecting the geometrical ∥D∇φ∥2+∥γ∥2=∥b∥2\|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 ϵ→0\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

    A Web-Services-Based P2P Computing-Power Sharing Architecture

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    As demands of data processing and computing power are increasing, existing information system architectures become insufficient. Some organizations try to figure out how to keep their systems work without purchasing new hardware and software. Therefore, a Webservices-based model which shares the resource over the network like a P2P network will be proposed to meet this requirement in this paper. In addition, this paper also discusses some problems about security, motivation, flexibility, compatibility and workflow management for the traditional P2P power sharing models. Our new computing architecture - Computing Power Services (CPS) - will aim to address these problems. For the shortcomings about flexibility, compatibility and workflow management, CPS utilizes Web Services and Business Process Execution Language (BPEL) to overcome them. Because CPS is assumed to run in a reliable network where peers trust each other, the concerns about security and motivation will be negated. In essence, CPS is a lightweight Web-Services-based P2P power sharing environment and suitable for executing computing works in batch in a reliable networ

    Outcome after endovascular stent graft treatment for mycotic aortic aneurysm: A systematic review

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    BackgroundSurgical treatment for mycotic aortic aneurysms is not optimal. Even with a large excision, extensive debridement, in situ or extra-anatomical reconstruction, and with or without lifelong antibiotic treatment, mycotic aneurysms still carry very high mortality and morbidity. The use of endovascular aneurysm repair (EVAR) for mycotic aortic aneurysms simplifies the procedure and provides a good alternative for this critical condition. However, the question remains: if EVAR is placed in an infected bed, what is the outcome of the infection? Does it heal, become aggravated, or even cause a disastrous aortic rupture? In this study, we tried to clarify the risk factors for such an adverse response.MethodsA literature review was undertaken by using MEDLINE. All relevant reports on endoluminal management of mycotic aortic aneurysms were included. Logistic regressions were applied to identify predictors of persistent infection.ResultsA total of 48 cases from 22 reports were included. The life-table analysis showed that the 30-day survival rate was 89.6% ± 4.4%, and the 2-year survival rate was 82.2% ± 5.8%. By univariate analysis, age 65 years or older, rupture of the aneurysm (including those with aortoenteric fistula and aortobronchial fistula), and fever at the time of operation were identified as significant predictors of persistent infection, and preoperative use of antibiotics for longer than 1 week and an adjunct procedure combined with EVAR were identified as significant protective factors for persistent infection. However, by multivariate logistic regression analysis, the only significant independent predictors identified were rupture of aneurysm and fever.ConclusionsEVAR seems a possible alternative method for treating mycotic aortic aneurysms. Identification of the risk factors for persistent infection may help to decrease surgical morbidity and mortality. EVAR could be used as a temporary measure; however, a definite surgical treatment should be considered for patients present with aneurysm rupture or fever
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