关于集合的粗相似度量的注记

举例说明文献"集合的粗相似度量"中定理3.1(2)的结论是不严谨的,从而给出一个严谨的结论。     

Orbital Angular Momentum Generation Using Circular Ring Resonators in Radio Frequency

Electromagnetic field generators based on circular ring resonators,whose perimeters are integer times of equivalent wavelength,are well known to have attractive potential for producing radio vortexes carrying orbital angular momentum(OAM).We study the radiation characteristics of the generators based on radiation vector and antenna array theory.The behaviors of radiation patterns,field intensity and phase distribution are investigated in detail,and show classical features of OAM beams.The evolution of the generators performance versus the OAM state is also analyzed.The proposed generators can be realized by all kinds of microwave transmission lines,verified by two different prototypes.The discussions and conclusions drawn in this study are useful and meaningful for the radio OAM generator design.     

一类特殊曲线积分的计算

利用无界广义第二类曲线积分的定义,针对一类特殊曲线积分给出了几种计算技巧和方法.通过实例说明这类曲线积分的值与积分路径有关.     

基于可辨识矩阵的模糊目标系统决策约简算法

在模糊目标信息系统决策约简和可辨识矩阵定义的基础上,讨论了可辨识矩阵的性质以及与决策约简集之间的关系.同时定义一种新的属性重要度,并将此作为启发式信息,设计了一种模糊目标决策信息系统最小决策约简算法,通过实例验证该算法简捷、有效.     

基于超材料的椭圆形电磁波聚焦器设计

基于变换光学方法,导出了椭圆形电磁聚焦器的介电常量和磁导率的分布,并用有限元分析软件COMSOL进行了证实.仿真了椭圆形电磁聚焦器聚焦区域面积大小和电磁参量偏离理论值对其聚焦特性的影响,结果表明:聚焦区域越小,电磁聚焦越强;超材料损耗小于或等于0.01不影响聚焦特性;当椭圆形变化为圆形时,其聚焦特性与Rahm等人获得的圆形聚焦器的结果一致,证明了本文建立电磁模型的有效性.     

Design method of reusable reciprocal invisibility and phantom device

Reusable reciprocal invisibility and phantom device is proposed and designed based on multi-folded transformation optics and equivalent components. In comparison with the reported reciprocal invisibility cloaks, the material parameters of the device presented here are homogeneous, and the hiding of the target object does not require any "anti-object" at all, which dramatically breaks through the limitations of the "anti-object" design in previous reciprocal cloak design. Perfectly illusion effect is also found by reasonably setting the material parameters of the restored medium of the device, which can be used to confuse detection radars while hiding target objects. Last but not least, the proposed device has an open structure, which enables the target object enclosed by the device to perform material exchange and simplex transfer of information with the outside world through open channels. In other words, the proposed device has a reusable function, enabling stealth or phantom of new target objects without changing any parameters of the device.