随着高性能战斗机和航天宇宙飞船的应用,高空环境对飞行员的损伤给他们带来了严峻的挑战.其中,正加速度(+Gz)暴露后消化性溃疡的发病率和复发率在进一步提高.溃疡复发是现代医学的难点,与溃疡愈合质量(quality of ulcer healing,QOUH)...随着高性能战斗机和航天宇宙飞船的应用,高空环境对飞行员的损伤给他们带来了严峻的挑战.其中,正加速度(+Gz)暴露后消化性溃疡的发病率和复发率在进一步提高.溃疡复发是现代医学的难点,与溃疡愈合质量(quality of ulcer healing,QOUH)密切相关,提高QOUH被认为是对消化性溃疡认识的第3次飞跃,已成为目前航天航空医学的主要研究热点.本文从胃溃疡动物模型的建立、溃疡愈合质量的评价、+Gz对溃疡愈合质量影响的相关因素、实际应用等方面,对+Gz对大鼠实验性QOUH影响的研究进展进行综述,旨在促进相关的应用基础研究和提高针对高+Gz损伤的胃肠防护,进而增强飞行员的整体抗+Gz能力,提高飞行的安全性.展开更多
Phase carried by two orthogonal polarizations can be manipulated independently by controlling both the geometric size and orientation of the dielectric nanopost.With this characteristic,we demonstrate a novel multifun...Phase carried by two orthogonal polarizations can be manipulated independently by controlling both the geometric size and orientation of the dielectric nanopost.With this characteristic,we demonstrate a novel multifunctional metasurface,which converts part of the incident linearly polarized light into its cross-polarization and encodes the phase of the two orthogonal polarizations independently.A beam splitter and a bifocal metalens were realized in a single-layer dielectric metasurface by this approach.We fabricated the bifocal metalens and demonstrated that two focal spots in orthogonal polarizations can be separated transversely or longitudinally at will.The proposed approach shows a new route to design multifunctional metasurfaces with various applications in holography and three-dimensional display.展开更多
为了满足5G垂直用户对于网络切片部署时细粒度安全隔离需求,同时兼顾用户的隔离需求和提高资源利用率,提出了一种基于改进BN模型的网络切片安全部署方法。首先提出了一种双层BN模型的网络切片部署架构,基于SBA(service based architectu...为了满足5G垂直用户对于网络切片部署时细粒度安全隔离需求,同时兼顾用户的隔离需求和提高资源利用率,提出了一种基于改进BN模型的网络切片安全部署方法。首先提出了一种双层BN模型的网络切片部署架构,基于SBA(service based architecture)设计了虚拟机容器的双层虚拟化架构,将网络切片根据其所属用户的隔离需求分配利益冲突类标签,基于改进的BN模型部署规则确定网络切片的隔离部署策略;然后将该部署方法建立为整数线性规划模型,并将部署成本作为目标函数,通过最小化目标函数实现低成本部署网络切片;最后使用遗传算法对该问题仿真求解。实验结果表明,该安全部署方法在满足网络切片安全隔离需求的前提下降低了部署成本。展开更多
文摘随着高性能战斗机和航天宇宙飞船的应用,高空环境对飞行员的损伤给他们带来了严峻的挑战.其中,正加速度(+Gz)暴露后消化性溃疡的发病率和复发率在进一步提高.溃疡复发是现代医学的难点,与溃疡愈合质量(quality of ulcer healing,QOUH)密切相关,提高QOUH被认为是对消化性溃疡认识的第3次飞跃,已成为目前航天航空医学的主要研究热点.本文从胃溃疡动物模型的建立、溃疡愈合质量的评价、+Gz对溃疡愈合质量影响的相关因素、实际应用等方面,对+Gz对大鼠实验性QOUH影响的研究进展进行综述,旨在促进相关的应用基础研究和提高针对高+Gz损伤的胃肠防护,进而增强飞行员的整体抗+Gz能力,提高飞行的安全性.
基金the National Natural Science Foundation of China(NSFC)(Nos.11674303 and 11574293)the Anhui Provincial Science andTechnology Major Projects(No.18030901005)。
文摘Phase carried by two orthogonal polarizations can be manipulated independently by controlling both the geometric size and orientation of the dielectric nanopost.With this characteristic,we demonstrate a novel multifunctional metasurface,which converts part of the incident linearly polarized light into its cross-polarization and encodes the phase of the two orthogonal polarizations independently.A beam splitter and a bifocal metalens were realized in a single-layer dielectric metasurface by this approach.We fabricated the bifocal metalens and demonstrated that two focal spots in orthogonal polarizations can be separated transversely or longitudinally at will.The proposed approach shows a new route to design multifunctional metasurfaces with various applications in holography and three-dimensional display.
文摘为了满足5G垂直用户对于网络切片部署时细粒度安全隔离需求,同时兼顾用户的隔离需求和提高资源利用率,提出了一种基于改进BN模型的网络切片安全部署方法。首先提出了一种双层BN模型的网络切片部署架构,基于SBA(service based architecture)设计了虚拟机容器的双层虚拟化架构,将网络切片根据其所属用户的隔离需求分配利益冲突类标签,基于改进的BN模型部署规则确定网络切片的隔离部署策略;然后将该部署方法建立为整数线性规划模型,并将部署成本作为目标函数,通过最小化目标函数实现低成本部署网络切片;最后使用遗传算法对该问题仿真求解。实验结果表明,该安全部署方法在满足网络切片安全隔离需求的前提下降低了部署成本。
