设计了一种由一维光波导构成的一维双金字塔光波导网络,利用网络方程、无量纲布洛赫定理、以及广义本征函数方法研究了这种光波导网络的光子带隙和光子衰减性质。研究发现:这种包含高密度三角形基元回路的有趣光波导网络能够产生巨大的完全光子带隙和超强的光子衰减。当网络中任意两个相邻结点都由波导长度配比为2∶1的两条一维波导线连接时,网络产生的光子带隙的中心带隙率可达到154%;仅仅包含8个原胞的这种2∶1双连通光波导网络,其光子带隙的平均衰减深度可超过10-21(这相当于-210 d B)。这种有趣的光波导网络可用于设计和开发宽带隙和强局域的光子器件。
Highly detailed surface models and their real-time applications are increasingly popular in architecture,construction and other design and engineering fields.However,new and related problems have emerged concerning the efficient management of the resulting large datasets and the seamless integration of heterogeneous data.Moreover,the increasingly common requirements of local high-fidelity modeling combined with large-scale landscapes lead to difficulty in the seamless multi-resolution representation of hybrid triangulated irregular networks(TINs)and Grids.This paper presents a hybrid data structure with high-efficiency and a related organizational method for the seamless integration of multi-resolution models.This approach is characterized by(1)a self-adaptive algorithm for feature-preserving surface partitioning,(2)an efficient hybrid index structure for combined Grid and TIN surfaces,and(3)a view-dependent scheduling strategy with access to Grids of necessary resolution,giving priority to the dynamic loading of TINs.Experiments using typical real design datasets of highway constructions are able to achieve accuracy-preserved and real-time availability of results that prove the validity and efficiency of this approach.
