529 research outputs found

    Application of Artificial Neural Networks in Predicting Abrasion Resistance of Solution Polymerized Styrene-Butadiene Rubber Based Composites

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    Abrasion resistance of solution polymerized styrene-butadiene rubber (SSBR) based composites is a typical and crucial property in practical applications. Previous studies show that the abrasion resistance can be calculated by the multiple linear regression model. In our study, considering this relationship can also be described into the non-linear conditions, a Multilayer Feed-forward Neural Networks model with 3 nodes (MLFN-3) was successfully established to describe the relationship between the abrasion resistance and other properties, using 23 groups of data, with the RMS error 0.07. Our studies have proved that Artificial Neural Networks (ANN) model can be used to predict the SSBR-based composites, which is an accurate and robust process

    Establishment of China Information Technology Outsourcing Early Warning Index Based on SVR

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    AbstractInformation technology outsourcing in China has developed fast, it plays a more and more important role in economic development of China. Economic analysis and early warning system of information technology outsourcing, which reflect the status of ITO, can promote the healthy development of the industry. This paper constructed the indicator system by the method of time difference relevance and peak-valley. The weight vector of each indicator is attained by using support vector regression. It also calculated the comprehensive early warning index and established the early warning index system. At last, we used a group of signal lamps to reflect the status at every time. Based on the reality of ITO in China, this paper found that the development speed of ITO is slowing in recent months, the government should take out some positive measures

    Delving StyleGAN Inversion for Image Editing: A Foundation Latent Space Viewpoint

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    GAN inversion and editing via StyleGAN maps an input image into the embedding spaces (W\mathcal{W}, W+\mathcal{W^+}, and F\mathcal{F}) to simultaneously maintain image fidelity and meaningful manipulation. From latent space W\mathcal{W} to extended latent space W+\mathcal{W^+} to feature space F\mathcal{F} in StyleGAN, the editability of GAN inversion decreases while its reconstruction quality increases. Recent GAN inversion methods typically explore W+\mathcal{W^+} and F\mathcal{F} rather than W\mathcal{W} to improve reconstruction fidelity while maintaining editability. As W+\mathcal{W^+} and F\mathcal{F} are derived from W\mathcal{W} that is essentially the foundation latent space of StyleGAN, these GAN inversion methods focusing on W+\mathcal{W^+} and F\mathcal{F} spaces could be improved by stepping back to W\mathcal{W}. In this work, we propose to first obtain the precise latent code in foundation latent space W\mathcal{W}. We introduce contrastive learning to align W\mathcal{W} and the image space for precise latent code discovery. %The obtaining process is by using contrastive learning to align W\mathcal{W} and the image space. Then, we leverage a cross-attention encoder to transform the obtained latent code in W\mathcal{W} into W+\mathcal{W^+} and F\mathcal{F}, accordingly. Our experiments show that our exploration of the foundation latent space W\mathcal{W} improves the representation ability of latent codes in W+\mathcal{W^+} and features in F\mathcal{F}, which yields state-of-the-art reconstruction fidelity and editability results on the standard benchmarks. Project page: \url{https://github.com/KumapowerLIU/CLCAE}

    A hybrid Hermite WENO scheme for hyperbolic conservation laws

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    In this paper, we propose a hybrid finite volume Hermite weighted essentially non-oscillatory (HWENO) scheme for solving one and two dimensional hyperbolic conservation laws. The zeroth-order and the first-order moments are used in the spatial reconstruction, with total variation diminishing Runge-Kutta time discretization. The main idea of the hybrid HWENO scheme is that we first use a shock-detection technique to identify the troubled cell, then, if the cell is identified as a troubled cell, we would modify the first order moment in the troubled cell and employ HWENO reconstruction in spatial discretization; otherwise, we directly use high order linear reconstruction. Unlike other HWENO schemes, we borrow the thought of limiter for discontinuous Galerkin (DG) method to control the spurious oscillations, after this procedure, the scheme would avoid the oscillations by using HWENO reconstruction nearby discontinuities and have higher efficiency for using linear approximation straightforwardly in the smooth regions. In addition, the hybrid HWENO scheme still keeps the compactness. A collection of benchmark numerical tests for one and two dimensional cases are performed to demonstrate the numerical accuracy, high resolution and robustness of the proposed scheme.Comment: 38 page

    Joint Optimization of Preventive Maintenance and Spare Parts Inventory with Appointment Policy

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    Under the background of the wide application of condition-based maintenance (CBM) in maintenance practice, the joint optimization of maintenance and spare parts inventory is becoming a hot research to take full advantage of CBM and reduce the operational cost. In order to avoid both the high inventory level and the shortage of spare parts, an appointment policy of spare parts is first proposed based on the prediction of remaining useful lifetime, and then a corresponding joint optimization model of preventive maintenance and spare parts inventory is established. Due to the complexity of the model, the combination method of genetic algorithm and Monte Carlo is presented to get the optimal maximum inventory level, safety inventory level, potential failure threshold, and appointment threshold to minimize the cost rate. Finally, the proposed model is studied through a case study and compared with both the separate optimization and the joint optimization without appointment policy, and the results show that the proposed model is more effective. In addition, the sensitivity analysis shows that the proposed model is consistent with the actual situation of maintenance practices and inventory management
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