Stratobus平流层飞艇项目研究进展与仿真分析

平流层飞艇是当前的前沿热点研究方向,创新性强、技术挑战大。针对国外公开在研的大型超长航时平流层飞艇项目Stratobus,首先对基本方案进行总结分析,梳理总体研究进展,然后归纳剖析囊体材料、太阳电池、可再生氢氧燃料电池、吊舱移动系统等核心关键技术方案和研究进展,在此基础上,通过数值仿真,对决定平流层飞艇总体方案可行性的浮重平衡、推阻平衡、能源平衡进行综合分析,提出了Stratobus项目发展的启示,为平流层飞艇总体设计和研究发展提供参考借鉴。     

改进的三维高精度通用单胞模型

基于复合材料细观力学周期性假设,对高精度通用单胞模型进行了改进,并推广到三维。模型中用界面的平均量代替细观位移函数中解系数,并利用细观单元力学方程的分析与求解,建立了细观平均量与复合材料宏观平均量间的联系.改进的高精度通用单胞模型的求解方程数目减少了大约55%,求解时间缩短,并且消除了亚子胞的概念.算例分析表明该模型的计算结果与细观有限元结果具有较好的一致性.      

薄膜太阳能电池光电转换材料研究进展

在对太阳能电池基本原理进行介绍的基础上,综述了近年来光电转换材料的发展情况,重点对各种材料的优缺点、制备方法以及未来的发展趋势进行探讨。     

Learning Spatial Localization: From Rat Studies to Computational Models of the Hippocampus

In his landmark article, Richard Morris (1981) introduced a set of rat experiments intended “to demonstrate that rats can rapidly learn to locate an object that they can never see, hear, or smell provided it remains in a fixed spatial location relative to distal room cues” (p. 239). These experimental studies have greatly impacted our understanding of rat spatial cognition. In this article, we address a spatial cognition model primarily based on hippocampus place cell computation where we extend the prior Barrera–Weitzenfeld model (2008) intended to allow navigation in mazes containing corridors. The current work extends beyond the limitations of corridors to enable navigation in open arenas where a rat may move in any direction at any time. The extended work reproduces Morris's rat experiments through virtual rats that search for a hidden platform using visual cues in a circular open maze analogous to the Morris water maze experiments. We show results with virtual rats comparing them to Morris's original studies with rats.