超宽带高功率电磁脉冲天线的设计与实验

在对近辐射场动力学过程辐射的研究基础上，提出能辐射超宽带电磁脉冲的综合天线的概念及天线试验研究的结果。研制此天线利用了能量应用这种概念，其有小的尺寸，高的电场强度，线极化辐射脉冲的中心形曲线图，并且完全适合作为扫描天线阵扫描单元。此天线由高压双极性脉冲发生器激励。     

基于心形线特性的锚固洞体型优化研究

针对预留锚固洞对拉锚索的锚固方式,传统梯形锚固洞周围拉应力过大的问题,以某工程预应力闸墩中墩为研究对象,建立三维有限元模型,根据心形曲线的几何特性,提出了心形锚固洞体型,在不同的荷载组合下,对梯形和心形锚固洞进行了对比分析,并对其设计参数做了深入研究。结果表明:心形锚固洞与传统梯形锚固洞相比,周围拉应力明显降低,受力情况更好;将心形锚固洞上游曲面改为铅直面,能有效控制锚固洞体积,且在满足施工情况下,可尽量靠近下游面中心;心形锚固洞顶面与下游面交线到顶层锚索中心距离取1. 5～2. 0m,底面与下游面交线到底层锚索中心距离取1. 2～1. 5m,较为合理。     

From Spheroids to Organoids: The Next Generation of Model Systems of Human Cardiac Regeneration in a Dish

Organoids are tiny, self-organized, three-dimensional tissue cultures that are derived from the differentiation of stem cells. The growing interest in the use of organoids arises from their ability to mimic the biology and physiology of specific tissue structures in vitro. Organoids indeed represent promising systems for the in vitro modeling of tissue morphogenesis and organogenesis, regenerative medicine and tissue engineering, drug therapy testing, toxicology screening, and disease modeling. Although 2D cell cultures have been used for more than 50 years, even for their simplicity and low-cost maintenance, recent years have witnessed a steep rise in the availability of organoid model systems. Exploiting the ability of cells to re-aggregate and reconstruct the original architecture of an organ makes it possible to overcome many limitations of 2D cell culture systems. In vitro replication of the cellular micro-environment of a specific tissue leads to reproducing the molecular, biochemical, and biomechanical mechanisms that directly influence cell behavior and fate within that specific tissue. Lineage-specific self-organizing organoids have now been generated for many organs. Currently, growing cardiac organoid (cardioids) from pluripotent stem cells and cardiac stem/progenitor cells remains an open challenge due to the complexity of the spreading, differentiation, and migration of cardiac muscle and vascular layers. Here, we summarize the evolution of biological model systems from the generation of 2D spheroids to 3D organoids by focusing on the generation of cardioids based on the currently available laboratory technologies and outline their high potential for cardiovascular research.     

自动心向量图机系统

充分利用了8031的特点研制一种利用单片机控制的自动心向量图机,并对系统的组成作了详细论述,该设备获得较高的计算精度,为了提高程序的通用性和实用性,使一般技术人员能够使用,对于前处理、主程序和后处理部分进行了处理,使计算程序在向通用化、商业化发展的方向上迈进一步。     

心形线双曲拱坝三维建模

心形线作为几何数学上最美最浪漫的一条曲线,第一次在拱坝设计中研 究应用。在研究心形线几何特性时,发现有一段非常扁平的曲线,作为拱坝中轴线非常适合, 可以使得拱坝的合力方向向山里偏转,有利于坝肩的稳定。因此,研究心形线作为拱坝的一 种新线形,理论上具有可行性,并在实际工程中有一定的应用参考价值。该文在研究心形线 双曲拱坝各种参数的基础上,建立心形线双曲拱坝的数学方程,实现图形的三维建模,为拱 坝下一步进行有限元分析提供精确的三维模型,也为今后拱坝坝型的设计提供更多的选择和 有意义的参考。     

Rosettes and Other Arrangements of Circles

The process of design in art and architecture generally involves the combination and manipulation of a relatively small number of geometric elements to create both the underlying structures as well as the overlaid decorative details. In this paper we concentrate on patterns created by copies of just a single geometric form—the circle. The circle is an extremely significant shape. By virtue of its simplicity and its topology it has been highly esteemed by many different cultures for millennia, symbolising God, unity, perfection, eternity, stability, etc.