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1.
Face aging (FA) for young faces refers to rendering the aging faces at target age for an individual, generally under 20s, which is an important topic of facial age analysis. Unlike traditional FA for adults, it is challenging to age children with one deep learning-based FA network, since there are deformations of facial shapes and variations of textural details. To alleviate the deficiency, a unified FA framework for young faces is proposed, which consists of two decoupled networks to apply aging image translation. It explicitly models transformations of geometry and appearance using two components: GD-GAN, which simulates the Geometric Deformation using Generative Adversarial Network; TV-GAN, which simulates the Textural Variations guided by the age-related saliency map. Extensive experiments demonstrate that our method has advantages over the state-of-the-art methods in terms of synthesizing visually plausible images for young faces, as well as preserving the personalized features.  相似文献   
2.
Cobalt-incorporated MCM-41(Co-MCM-41) was used as a heterogeneous catalyst for the ozonation of para-chlorobenzoic acid (p-CBA) in aqueous solution. Cobalt oxide supported on MCM-41(Co/MCM-41) was synthesized for comparison. Their textural properties were elucidated by various characterization techniques to understand the relationship between surface texture and catalytic activity. TOC removal at 60 min reached 91% with Co-MCM-41, 83% with Co/MCM-41 and only 52% with ozone alone, respectively. Observations from diffuse reflection spectroscopy demonstrated that different metal phases were formed in these cobalt-modified molecular sieves samples. Radical scavenger experiments indicated the formation of hydroxyl radicals that were responsible for the effective degradation of p-CBA. An integrated approach to the catalytic mechanism was proposed by considering the variation of pH in the course of ozonation as well as its subsequent influence on the dissociation of targeted compounds and surface charge of the catalyst. In the reusability experiments, the reused Co-MCM-41 was able to regain the same catalytic capability as the fresh one within 5 cycles. X-ray photoelectron spectroscopy results indicated that a part of Co2+ was oxidized to Co3+ after oxidation reaction.  相似文献   
3.
We present a new image reconstruction method for Electrical Capacitance Tomography (ECT). ECT image reconstruction is generally ill-posed because the number of measurements is small whereas the image dimensions are large. Here, we present a sparsity-inspired approach to achieve better ECT image reconstruction from the small number of measurements. Our approach for ECT image reconstruction is based on Total Variation (TV) regularization. We apply an efficient Split-Bregman Iteration (SBI) approach to solve the problem. We also propose three metrics to evaluate image reconstruction performance, i.e., a joint metric of positive reconstruction rate (PRR) and false reconstruction rate (FRR), correlation coefficient, and a shape and location metric. The results on both synthetic and real data show that the proposed TV-SBI method can better preserve the edges of images and better resolve different objects within reconstructed images, as compared to a representative state-of-the-art ECT image reconstruction algorithm, Projected Landweber Iteration with Linear Back Projection initialization (LBP-PLI).  相似文献   
4.
A finite-difference Total Variation Diminishing (TVD) numerical simulation model for coupling the Reynolds Averaged Navier-Stokes (RANS) equations, pressure-relative continuity equation and various k-ε turbulence models was developed to solve the incompressible flow based on the pseudo-compressibility method. The hyperbolicity of all these equations was studied and the discretization of the fully coupling equations with all the primal variables and source terms were made in this article. Numerical simulation for modeling the flow around a ground-mounted square rib was implemented and validated by comparing with the published wind tunnel experimental data. It is shown that such a numerical simulation method with a proper turbulence model has a very good accuracy to simulate the flow around a surface-mounted rib. It is concluded that the Renormalization Group (RNG) and Chen-Kim k-ε turbulence models have much better ability to predict the characteristics of the vortex structure and flow separation than the standard k-ε model.  相似文献   
5.
本文以渤中28-1(BZ28-1)油田N6H水平井为例,从多方面对该井的动态和产能变化进行了系统分析,所用的方法对水平井动态分析有一定的指导意义。  相似文献   
6.
Many studies on non-rigid assemblies, or assemblies of non-rigid components, suggest that the component variation affects the assembly dimensional quality. However, little is known about how the variation of surface micro-geometry of assembly components influences the assembly dimensional quality. In this paper, a new method based on the fractal geometry and finite element method (FEM) is proposed to study such an influence. In the new method, a special fractal function, named the Weierstrass–Mandelbrot (W–M) function, is used to extract and represent the characteristics of surface micro-geometry of assembly components. FEM is applied to analyze the deformation of non-rigid assemblies by integrating the variation of component micro-geometry. The sensitivity matrix between the component variation and assembly variation is obtained by using the existing influence coefficients method. It is found that contributions of the surface micro-geometry of assembly components to the final variation of non-rigid assemblies could be substantial under certain conditions. The proposed method is illustrated through a case study on an assembly of two flat sheet metal components under different fixture-releasing conditions.  相似文献   
7.
This paper describes the design and application of the Atmospheric Evaluation and Research Integrated model for Spain (AERIS). Currently, AERIS can provide concentration profiles of NO2, O3, SO2, NH3, PM, as a response to emission variations of relevant sectors in Spain. Results are calculated using transfer matrices based on an air quality modelling system (AQMS) composed by the WRF (meteorology), SMOKE (emissions) and CMAQ (atmospheric-chemical processes) models. The AERIS outputs were statistically tested against the conventional AQMS and observations, revealing a good agreement in both cases. At the moment, integrated assessment in AERIS focuses only on the link between emissions and concentrations. The quantification of deposition, impacts (health, ecosystems) and costs will be introduced in the future. In conclusion, the main asset of AERIS is its accuracy in predicting air quality outcomes for different scenarios through a simple yet robust modelling framework, avoiding complex programming and long computing times.  相似文献   
8.
在利用航海雷达进行海浪观测时,降雨的出现会改变海面粗糙度,从而导致雷达所接收到的回波信号强度发生改变。通过对实际海浪观测资料的分析,提出一种对航海雷达测波系统中降雨观测资料的分析与处理方法,运用雷达回波影像的统计特性-均值和变异系数作为降雨与非降雨雷达影像的分类标准,然后利用中值滤波算法对降雨观测资料进行滤波处理,以降低降雨对回波影像的影响,同时探讨了中值滤波算法的适用性。实验结果表明本算法具有较强的鲁棒性和较高的通用性。  相似文献   
9.
As an important part of water level warning in water conservancy projects, often due to the influence of en-vironmental factors such as light and stains, the acquired water gauge images have sticky, broken and bright spot conditions, which affect the identification of water gauges. To solve this problem, a water gauge image denoising model based on improved adaptive total variation is proposed. Firstly, the regular term exponent in the adaptive total variational equation is changed to an inverse cosine function; secondly, the differential curvature is used to distinguish the image noise points and increase the smoothing strength at the noise points; finally, according to the characteristics of the gradient mode and adaptive gradient threshold after Gaussian filtering, the New model can adaptively denoise in the smooth area and protect the edge area, so as to have the characteristics of both edge-preserving denoising. The experimental results show that the new model has a great improvement in image vision, higher iteration efficiency and an average increase of 1.6 dB in peak signal-to-noise ratio, and an average increase of 9% in structural similarity, which is more beneficial to practical applications.  相似文献   
10.
By combining Cluster Variation Method with FLAPW electronic structure total energy calculations and the Debye–Grüneisen theory within quasi-harmonic approximation, L10-disorder phase equilibria for Fe–Ni system are calculated. The transition temperature, 483 K, determined in the present calculation is lower than that obtained in the previous calculation without thermal vibration effects. The decrease of the transition temperature is ascribed to the enhanced phase stability of a disordered phase due to the thermal softening of a lattice.  相似文献   
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