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periodic structure 循環結構。

periodic system

The results showed that the interplanar spacing d values and relative x - ray diffraction intensity of the mixed lb films change with the ratio of ba / sa in a step - and w - shaped curve respectively , which indicates that only three kinds of longitudinal periodic structures can form in the mixed multilayer lb films of all ratios and each microstructure can be maintained in a certain ratio range . furthermore the mixed system always goes through a process of the longitudinal regularity decreasing when the ratio of ba / sa is out of the intermediate ratio range ( ba / sa : 1 / 5 ~ 1 / 1 ) 結果發現,對于sa ba混合膜,分相小而均勻,不出現單獨的衍射周期;隨比例不同,縱向面間距出現臺階效應,表明存在3類結構,其中在較大比例范圍內出現了長短鏈交錯的結構,這種結構具有高的穩定性和有序性;在ba較多的混合膜中,在脂鏈層間出現空洞結構,可以用來構造特殊的納米結構。

In 6 . 635 , topics covered include : special relativity , electrodynamics of moving media , waves in dispersive media , microstrip integrated circuits , quantum optics , remote sensing , radiative transfer theory , scattering by rough surfaces , effective permittivities , random media , green ' s functions for planarly layered media , integral equations in electromagnetics , method of moments , time domain method of moments , em waves in periodic structures : photonic crystals and negative refraction 本課程所覆蓋的論題包括:狹義相對論、運動媒質的電動力學、色散媒質中的波、微帶集成電路、量子光學、遙感、輻射傳輸理論、粗糙表面上的散射、有效介電系數、隨機媒質、平面層狀媒質的格林函數、電磁學中的積分方程、矩量法、時域矩量法、周期結構中的電磁波:光子晶體和負折射率。

First , the fundamental theory of the basic fdtd method and its application in the analysis of the electromagnetic properties of infinite planar periodic structures is summarized . the basic ideas of the auxiliary fields fdtd method is expressed and generalized to the situations of the 2 - d periodic structures , to lossy media , and to the curvilinear coordinate . the shortcoming of this method in the management of conformal grids is pointed out 首先總結了fdtd方法的基本理論及其在周期性結構電磁特性分析中的應用,闡述了輔助場fdtd方法的基本思想,把它推廣到二維周期性的情況和計算區域為有耗媒質的情況,再進一步推廣到曲線坐標系中,并指出了該方法在網格共形處理中的不利之處。

Then , the auxiliary fields fdtd is used to the periodic structure made of dispersive material , such as the pyramid absorbers in anechoic chamber . the permittivity vs frequency property of the absorber is approached by some dispersive equation model , such as debye model and lorentz model , so the broadband response of the absorber can be gotten through one calculation 然后將輔助場fdtd應用到色散媒質周期結構中,導出了色散媒質中的迭代式,并以暗室吸波材料陣列為例進行計算,提出用某一類型的介電常數色散函數(如debye型、 lorentz型等)來逼近材料的介電常數頻率特性的方法,從而可以對吸波材料進行一次性寬頻計算。

Some successes have been achieved through microfabrication techniques , but the pursuit of a microscopically ordered pbg in the visible range was still a challenging endeavor . colloidal self - assembly has been utilized as a process to form 3d periodic structures because of its simplicity 電磁流變技術的發展為廉價、簡便地形成三維有序結構以制備光子晶體提供了一條新的途徑,而這種方法的關鍵在于制備粒徑適當的電磁響應性微粒。

This method can be used to analyze the dispersive characteristic of arbitrary mode sws with arbitrary boundary in theory . considering the photonic crystal is also a periodic structure , this method can be also extended to analyze the band structure of photonic crystal 論文首先在直角坐標系下,給出了fdtd差分方程和周期性邊界條件的具體形式,并編寫程序,分析了周期性加載金屬片矩形波導的色散特性。

3 . on unusual phenomena in the one dimensional alternate structure of left - handed material and right - handed material i found three unusual phenomena for the one dimensional periodic structure consisting both left - handed material and right - handed material 我研究發現一維的正負材料交替的周期性結構有三個和普通的完全由正材料(或者負材料)組成的周期性結構反常的現象。

Photonic crystals have recently been studied extensively because they offer unique ways of tailoring the propagation of light . a number of methods have been developed to create the periodic structures possessing photonic band gap ( pbg ) 光子晶體是一種介電常數周期性變化排列的人工晶體,它提供了一種完全不同的新的控光機制,因而被稱為“光的半導體” 。

This thesis is devoted to the theory and the application of the auxiliary fields finite - difference time - domain ( fdtd ) , which is an analytic method of the electromagnetic properties of infinite planar periodic structures 本文主要研究了無限大平面周期性結構電磁特性的一種分析方法? ?輔助場fdtd方法的理論及其應用。

A frequency selective surface ( fss ) is a metallic periodic structure with frequency selective properties . depending upon design , it may be low - pass , high - pass , band - pass , band - stop filter 頻率選擇表面( fss )是具有選擇頻率功能的一塊金屬周期結構,它可以被設計成低通、高通、帶通、帶阻濾波器。

Photonic crystals is an artificial periodic structure with the characteristic of band suppression , which is composed of one kind of material in which another kind of material is periodically distributed 光子晶體pbg是一種介質材料在另一種介質材料中周期分布所形成的具有帶阻特性的人造周期性結構。

In this thesis , we propose a general framework of analyzing periodic structured scored game video ( such as tennis , table tennis ) 本文在原有體育視頻分析工作的基礎上提出了針對周期性結構的得分型比賽(如網球、乒乓球)的通用分析框架。

Periodic structure ( ps ) has been used in many applications such as slow wave structure ( sws ) and frequency selective surface 周期電磁結構有著廣泛的應用,常被用作頻率選擇表面或者高功率微波器件中的慢波結構等。

Based on the fore - mentioned theory , several typical kinds of periodic structures are analyzed using the auxiliary fields fdtd method 在前面的理論基礎之上,將輔助場fdtd方法應用于各種周期性結構的分析中。

Whereas its analysis appliance is restricted within the totally periodic structures such as super - lattice and quantum pots 但在此之前,對它的應用僅限于超晶格、量子點等完全規律性的材料。

Possibility of using periodic structure permanent magnetic ring as initial energy source for a magneto - cumulative generator 用周期鐵磁結構環作磁累積發生器的初始能源

Nonclassical heat conduction analysis in periodic structures with multiple spatial and temporal scales analysis method 周期性材料非經典熱傳導時空間多尺度分析方法

Analytical method of the subdomain basis functions for the transmitted characteristics of two - dimension periodic structure 二維周期結構傳輸特性的子域基函數分析法

Vector analysis for chromatic dispersion character - ristics of two - dimensionally periodic structure 二維周期結構色散特性的矢量理論分析