One program to simulation light passing through a glass sphere. It is interesting and can be used in geometric optics.
標簽： interesting simulation program passing
上傳時間： 2014-12-07
上傳用戶：璇珠官人
In an electromagnetic cloak based on a transformation approach, reduced sets of material properties are generally favored due to their easier implementation in reality, although a seemingly inevitable drawback of undesired reflection exists in such cloaks. Here we suggest using high-order transformations to create smooth moduli at the outer boundary of the cloak, therefore completely eliminating the detrimental scattering within the limit of geometric optics. We apply this scheme to a non-magnetic cylindrical cloak and demonstrate that the scattered field is reduced substantially in a cloak with optimal quadratic transformation as compared to its linear counterpart.
標簽： electromagnetic transformation properties approach
上傳時間： 2017-03-30
上傳用戶：pkkkkp
We obtained the energy transport velocity distribution for a three dimensional ideal cloak explicitly. Near the operation frequency, the energy transport velocity has rather peculiar distribution. The velocity along a line joining the origin of the cloak is a constant, while the velocity approaches zero at the inner boundary of the cloak. A ray pointing right into the origin of the cloak will experience abrupt changes of velocities when it impinges on the inner surface of the cloak. This peculiar distribution causes long time delays for beams passing through the ideal cloak within a geometric optics description.
標簽： distribution dimensional transport obtained
上傳時間： 2013-12-19
上傳用戶：zhliu007
對微機電系統(Micro electro mechanical systems，MEMS)組裝與封裝工藝的特點進行了總結分析，給出了MEMS組裝與封裝設備的研究現狀。針對MEMS產業發展的特點，分析了面向MEMS組裝與封裝的微操作設備中的工藝參數優化數據庫、快速精密定位、模塊化作業工具、快速顯微視覺、柔性裝夾和自動化物流等關鍵技術。在此基礎上，詳細介紹了研制的MEMS傳感器陽極化鍵合設備和引線鍵合設備的組成結構，工作原理，并給出了組裝和封裝試驗結果。最后，指出了MEMS組裝與封裝技術及設備研制的發展趨勢。
上傳時間： 2016-07-26
上傳用戶：leishenzhichui
This book describes the applications of the fundamental interactions of electromagnetic waves and materials as described in the preceding volume, “Basic Electromagnetism and Materials”. It is addressed to students studying masters or doctorate courses in electronics, electromagnetism, applied physics, materials physics, or chemical physics. In particular, this volume analyzes the behavior of materials in the presence of an electromagnetic field and related applications in the fields of electronics, optics, and materials physics.
標簽： Electromagnetism Materials Applied and
上傳時間： 2020-05-26
上傳用戶：shancjb
Free Space Optical Communication (FSOC) is an effective alternative technology to meet the Next Generation Network (NGN) demands as well as highly secured (mili- tary) communications. FSOC includes various advantages like last mile access, easy installation, free of Electro Magnetic Interference (EMI)/Electro Magnetic Compatibil- ity (EMC) and license free access etc. In FSOC, the optical beam propagation in the turbulentatmosphereisseverelyaffectedbyvariousfactorssuspendedinthechannel, geographicallocationoftheinstallationsite,terraintypeandmeteorologicalchanges. Therefore a rigorous experimental study over a longer period becomes significant to analyze the quality and reliability of the FSOC channel and the maximum data rate that the system can operate since data transmission is completely season dependent.
標簽： Communication Optical System Space Free
上傳時間： 2020-05-27
上傳用戶：shancjb
The field of digital communication has evolved rapidly in the past few decades, with commercial applications proliferating in wireline communi- cation networks (e.g., digital subscriber loop, cable, fiber optics), wireless communication (e.g., cell phones and wireless local area networks), and stor- age media (e.g., compact discs, hard drives). The typical undergraduate and graduate student is drawn to the field because of these applications, but is often intimidated by the mathematical background necessary to understand communication theory.
標簽： Communication Fundamentals Digital of
上傳時間： 2020-05-27
上傳用戶：shancjb
The use of optical free-space emissions to provide indoor wireless commu- nications has been studied extensively since the pioneering work of Gfeller and Bapst in 1979 [1]. These studies have been invariably interdisciplinary in- volving such far flung areas such as optics design? indoor propagation studies? electronics design? communications systems design among others. The focus of this text is on the design of communications systems for indoor wireless optical channels. Signalling techniques developed for wired fibre optic net- works are seldom efficient since they do not consider the bandwidth restricted nature of the wireless optical channel.
標簽： Communication Wireless Optical Systems
上傳時間： 2020-06-01
上傳用戶：shancjb
Static electricity is the most ancient form of electricity known to humans. More than 2000 years ago, the Greeks recognized the attraction between certain mate- rials when they were rubbed together; indeed, the word electricity comes from the Greek elektron, which means amber. During the seventeenth and eighteenth centuries, several key experiments were conducted to understand and measure static electricity. But the discovery of electromagnetism and its formidable break- through has rapidly outgrown interest in static electricity. Even today, where the industrial applications of static electricity are not insignificant, they cannot compare with those of electromagnetism and electrodynamics.
標簽： Understand Discharge Electro Static
上傳時間： 2020-06-05
上傳用戶：shancjb
The challenges associated with the design and implementation of Electro- static Discharge (ESD) protection circuits become increasingly complex as technology is scaled well into nano-metric regime. One must understand the behavior of semiconductor devices under very high current densities, high temperature transients in order to surmount the nano-meter ESD challenge. As a consequence, the quest for suitable ESD solution in a given technology must start from the device level. Traditional approaches of ESD design may not be adequate as the ESD damages occur at successively lower voltages in nano-metric dimensions.
標簽： Protection Circuit Device Design ESD and
上傳時間： 2020-06-05
上傳用戶：shancjb
