Through finite element numerical simulation and based on laminated plate theory, the effect of dimension on the torsion properties of uniform C/SiC composites pipe was studied to provide a theoretical guidance for pre...Through finite element numerical simulation and based on laminated plate theory, the effect of dimension on the torsion properties of uniform C/SiC composites pipe was studied to provide a theoretical guidance for preparing the C/SiC pipe with different dimensions. The results show that, with increasing length of pipe, the anti-torsion section coefficient of pipe increases whereas the torsion angle per unit length decreases. Increasing the length can improve the torsion property. Anti-torsion section coefficient rises with increasing internal radius, while the torsion angle per unit length decreases to a constant. With increasing thickness, the anti-torsion section coefficient increases whereas the amplitude decreases gradually, and the torsion angle per unit length is a constant. Increment of internal radius and thickness improves the torsion property finitely.展开更多
History matching is a critical step in reservoir numerical simulation algorithms.It is typically hindered by difficulties associated with the high-dimensionality of the problem and the gradient calculation approach.He...History matching is a critical step in reservoir numerical simulation algorithms.It is typically hindered by difficulties associated with the high-dimensionality of the problem and the gradient calculation approach.Here,a multi-step solving method is proposed by which,first,a Fast marching method(FMM)is used to calculate the pressure propagation time and determine the single-well sensitive area.Second,a mathematical model for history matching is implemented using a Bayesian framework.Third,an effective decomposition strategy is adopted for parameter dimensionality reduction.Finally,a localization matrix is constructed based on the single-well sensitive area data to modify the gradient of the objective function.This method has been verified through a water drive conceptual example and a real field case.The results have shown that the proposed method can generate more accurate gradient information and predictions compared to the traditional analytical gradient methods and other gradient-free algorithms.展开更多
三维穿衣人体重建,在计算机图形学和三维视觉领域占有重要地位,广泛应用于多个方向。人体穿衣的多样性和动作的复杂性使得穿衣人体的高保真重建变得极其困难。深度学习技术优化了数据特征提取、隐式几何表示和神经渲染等关键环节,也推...三维穿衣人体重建,在计算机图形学和三维视觉领域占有重要地位,广泛应用于多个方向。人体穿衣的多样性和动作的复杂性使得穿衣人体的高保真重建变得极其困难。深度学习技术优化了数据特征提取、隐式几何表示和神经渲染等关键环节,也推动了高保真穿衣人体重建技术的革命性进步。本文综述了人体重建的基本流程和组成模块,如各类输入数据、人体几何与动作表示、参数化模型以及三维到二维的渲染技术。同时,介绍了公开的穿衣人体数据集,简要回顾了近10年来人体重建算法的快速发展。本文详细探讨了几种主要的重建方法:稠密视角重建、非刚性运动重建(non-rigid structure from motion,NRSFM)、基于像素对齐的隐式几何重建以及生成模型方法。特别是,稠密视角重建能够生成高质量的人体几何,而NRSFM方法减少了对多视角的需求。基于像素对齐的方法重建细节丰富的人体几何,而生成模型方法利用多模态输入信息实现重建。最后总结了现有方法,并展望了未来研究方向,包括实现低成本高保真重建、加速重建过程和增强重建结果的可编辑性,以及在自然环境下进行重建的可能性。本文总结了近年来穿衣人体重建技术的进步,同时指出了未来研究可能集中的方向。展开更多
基金Funded by the National Natural Science Foundation of China(Nos.51772246,51272210,50902112,and U1737209)the Program for New Century Excellent Talents in University(NCET-13-0474)+1 种基金the Fundamental Research Funds for the Central Universities(3102017jg02001)the National Program for Support of Topnotch Young Professionals
文摘Through finite element numerical simulation and based on laminated plate theory, the effect of dimension on the torsion properties of uniform C/SiC composites pipe was studied to provide a theoretical guidance for preparing the C/SiC pipe with different dimensions. The results show that, with increasing length of pipe, the anti-torsion section coefficient of pipe increases whereas the torsion angle per unit length decreases. Increasing the length can improve the torsion property. Anti-torsion section coefficient rises with increasing internal radius, while the torsion angle per unit length decreases to a constant. With increasing thickness, the anti-torsion section coefficient increases whereas the amplitude decreases gradually, and the torsion angle per unit length is a constant. Increment of internal radius and thickness improves the torsion property finitely.
基金This study was supported by National Natural Science Foundation of China(Nos.52104017,51874044,51922007)Southern Marine Science and Engineering Guangdong Laboratory(Zhanjiang)(No.zjw-2019-04).
文摘History matching is a critical step in reservoir numerical simulation algorithms.It is typically hindered by difficulties associated with the high-dimensionality of the problem and the gradient calculation approach.Here,a multi-step solving method is proposed by which,first,a Fast marching method(FMM)is used to calculate the pressure propagation time and determine the single-well sensitive area.Second,a mathematical model for history matching is implemented using a Bayesian framework.Third,an effective decomposition strategy is adopted for parameter dimensionality reduction.Finally,a localization matrix is constructed based on the single-well sensitive area data to modify the gradient of the objective function.This method has been verified through a water drive conceptual example and a real field case.The results have shown that the proposed method can generate more accurate gradient information and predictions compared to the traditional analytical gradient methods and other gradient-free algorithms.
文摘三维穿衣人体重建,在计算机图形学和三维视觉领域占有重要地位,广泛应用于多个方向。人体穿衣的多样性和动作的复杂性使得穿衣人体的高保真重建变得极其困难。深度学习技术优化了数据特征提取、隐式几何表示和神经渲染等关键环节,也推动了高保真穿衣人体重建技术的革命性进步。本文综述了人体重建的基本流程和组成模块,如各类输入数据、人体几何与动作表示、参数化模型以及三维到二维的渲染技术。同时,介绍了公开的穿衣人体数据集,简要回顾了近10年来人体重建算法的快速发展。本文详细探讨了几种主要的重建方法:稠密视角重建、非刚性运动重建(non-rigid structure from motion,NRSFM)、基于像素对齐的隐式几何重建以及生成模型方法。特别是,稠密视角重建能够生成高质量的人体几何,而NRSFM方法减少了对多视角的需求。基于像素对齐的方法重建细节丰富的人体几何,而生成模型方法利用多模态输入信息实现重建。最后总结了现有方法,并展望了未来研究方向,包括实现低成本高保真重建、加速重建过程和增强重建结果的可编辑性,以及在自然环境下进行重建的可能性。本文总结了近年来穿衣人体重建技术的进步,同时指出了未来研究可能集中的方向。
