With the development of virtual reality (VR) technology, more and more industries are beginning to integrate with VR technology. In response to the problem of not being able to directly render the lighting effect of C...With the development of virtual reality (VR) technology, more and more industries are beginning to integrate with VR technology. In response to the problem of not being able to directly render the lighting effect of Caideng in digital Caideng scenes, this article analyzes the lighting model. It combines it with the lighting effect of Caideng scenes to design an optimized lighting model algorithm that fuses the bidirectional transmission distribution function (BTDF) model. This algorithm can efficiently render the lighting effect of Caideng models in a virtual environment. And using image optimization processing methods, the immersive experience effect on the VR is enhanced. Finally, a Caideng roaming interactive system was designed based on this method. The results show that the frame rate of the system is stable during operation, maintained above 60 fps, and has a good immersive experience.展开更多
Phase transitions involving oxygen ion extraction within the framework of the crystallographic relevance have been widely exploited for sake of superconductivity,ferromagnetism,and ion conductivity in perovskiterelate...Phase transitions involving oxygen ion extraction within the framework of the crystallographic relevance have been widely exploited for sake of superconductivity,ferromagnetism,and ion conductivity in perovskiterelated oxides.However,atomic-scale pathways of phase transitions and ion extraction threshold are inadequately understood.Here we investigate the atomic structure evolution of LaCoO_(3) films upon oxygen extraction and subsequent Co migration,focusing on the key role of epitaxial strain.The brownmillerite to Ruddlesden-Popper phase transitions are discovered to stabilize at distinct crystal orientations in compressive-and tensile-strained cobaltites,which could be attributed to in-plane and out-of-plane Ruddlesden-Popper stacking faults,respectively.A two-stage process from exterior to interior phase transition is evidenced in compressive-strained LaCoO_(2.5),while a single-step nucleation process leaving bottom layer unchanged in tensile-strained situation.Strain analyses reveal that the former process is initiated by an expansion in Co layer at boundary,whereas the latter one is associated with an edge dislocation combined with antiphase boundary.These findings provide a chemomechanical perspective on the structure regulation of perovskite oxides and enrich insights into strain-dependent phase diagram in epitaxial oxides films.展开更多
趋化性是指细菌微生物对环境中某些具有刺激性的化学物质产生的定向趋近或者远离的运动.这种与生俱来的能力对生物趋利避害和适应环境等具有重要的作用.为了研究趋化性运动,Evelyn Fox Keller和Lee Aaron Segel于20世纪70年代初提出了...趋化性是指细菌微生物对环境中某些具有刺激性的化学物质产生的定向趋近或者远离的运动.这种与生俱来的能力对生物趋利避害和适应环境等具有重要的作用.为了研究趋化性运动,Evelyn Fox Keller和Lee Aaron Segel于20世纪70年代初提出了一类抛物型偏微分方程系统用以描述细菌种群密度以及化学物质浓度的动态演化.这类系统尽管结构相对简单,但是其动力学性质丰富,并且能够很好地模拟细菌聚集这一趋化性运动中最重要的现象,因此近年来成为偏微分方程研究领域的热点之一.细菌聚集现象可以通过抛物方程组有限时间爆破解所产生的δ-函数进行数学模拟,也可以通过如尖峰解、内边界层解等具有鲜明空间集中特征的稳态解来模拟.前者已有多个综述文献对之进行详细介绍,而关于后者目前还没有任何综述文章,因此本文旨在填补这个空白并综述几类Keller-Segel型模型的稳态解(特别是尖峰解和内边界层解)及其定性性质.本文将着重介绍关于这类问题研究的经典结果和最新进展,以及这些结果研究中所发展出来的变分法、摄动理论和分叉理论等具有创造性的数学.本文还将介绍这类稳态解系统研究中一些未解决的问题.展开更多
文摘With the development of virtual reality (VR) technology, more and more industries are beginning to integrate with VR technology. In response to the problem of not being able to directly render the lighting effect of Caideng in digital Caideng scenes, this article analyzes the lighting model. It combines it with the lighting effect of Caideng scenes to design an optimized lighting model algorithm that fuses the bidirectional transmission distribution function (BTDF) model. This algorithm can efficiently render the lighting effect of Caideng models in a virtual environment. And using image optimization processing methods, the immersive experience effect on the VR is enhanced. Finally, a Caideng roaming interactive system was designed based on this method. The results show that the frame rate of the system is stable during operation, maintained above 60 fps, and has a good immersive experience.
基金This work was supported by the National Natural Science Foundation of China(No.22273065 and No.21673158)Science&Technology Commission of Shanghai Municipality(14DZ2261100).
基金supported by the National Natural Science Foundation of China(Grant Nos.52322212,52072400,52025025,and 52250402)。
文摘Phase transitions involving oxygen ion extraction within the framework of the crystallographic relevance have been widely exploited for sake of superconductivity,ferromagnetism,and ion conductivity in perovskiterelated oxides.However,atomic-scale pathways of phase transitions and ion extraction threshold are inadequately understood.Here we investigate the atomic structure evolution of LaCoO_(3) films upon oxygen extraction and subsequent Co migration,focusing on the key role of epitaxial strain.The brownmillerite to Ruddlesden-Popper phase transitions are discovered to stabilize at distinct crystal orientations in compressive-and tensile-strained cobaltites,which could be attributed to in-plane and out-of-plane Ruddlesden-Popper stacking faults,respectively.A two-stage process from exterior to interior phase transition is evidenced in compressive-strained LaCoO_(2.5),while a single-step nucleation process leaving bottom layer unchanged in tensile-strained situation.Strain analyses reveal that the former process is initiated by an expansion in Co layer at boundary,whereas the latter one is associated with an edge dislocation combined with antiphase boundary.These findings provide a chemomechanical perspective on the structure regulation of perovskite oxides and enrich insights into strain-dependent phase diagram in epitaxial oxides films.
文摘趋化性是指细菌微生物对环境中某些具有刺激性的化学物质产生的定向趋近或者远离的运动.这种与生俱来的能力对生物趋利避害和适应环境等具有重要的作用.为了研究趋化性运动,Evelyn Fox Keller和Lee Aaron Segel于20世纪70年代初提出了一类抛物型偏微分方程系统用以描述细菌种群密度以及化学物质浓度的动态演化.这类系统尽管结构相对简单,但是其动力学性质丰富,并且能够很好地模拟细菌聚集这一趋化性运动中最重要的现象,因此近年来成为偏微分方程研究领域的热点之一.细菌聚集现象可以通过抛物方程组有限时间爆破解所产生的δ-函数进行数学模拟,也可以通过如尖峰解、内边界层解等具有鲜明空间集中特征的稳态解来模拟.前者已有多个综述文献对之进行详细介绍,而关于后者目前还没有任何综述文章,因此本文旨在填补这个空白并综述几类Keller-Segel型模型的稳态解(特别是尖峰解和内边界层解)及其定性性质.本文将着重介绍关于这类问题研究的经典结果和最新进展,以及这些结果研究中所发展出来的变分法、摄动理论和分叉理论等具有创造性的数学.本文还将介绍这类稳态解系统研究中一些未解决的问题.
