多模干涉型集成光学器件研究进展

基于自镜像效应(SIE)的多模干涉(MMI)型集成光学器件是集成光学中具有广泛用途的重要器件。本文详细而系统地综述了近几年来MMI器在国内外的研究进展，特别是其在集成光学中的应用。     

Determining the role of the underlying orbital‐dependence of PBE0‐DH and PBE‐QIDH double‐hybrid density functionals

We study the orbital‐dependence of three (parameter‐free) double‐hybrid density functionals, namely the PBE0‐DH, the PBE‐QIDH models, and the SOS1‐PBE‐QIDH spin‐opposite‐scaled variant of the latter. To do it, we feed all their energy terms with different sets of orbitals obtained previously from self‐consistent density functional theory calculations using several exchange‐correlation functionals (e.g., PBE, PBE0, PBEH&H), or directly with HF‐PBE orbitals, to see their effect on selected datasets for atomization and reaction energies, the latter proned to marked self‐interaction errors. We find that the PBE‐QIDH double‐hybrid model shows a great consistency, as the best results are always obtained for the set of orbitals corresponding to its hybrid scheme, which prompts us to recommend this model without any other fitting or reparameterization. © 2017 Wiley Periodicals, Inc.     

GPIB测试母线在数据传输电路的应用

介绍了GPIB通用接口母线的特点及其优势,将其应用于单片机USB-GPIB框架的数据传输系统,其中USB部分Cypress公司基于2.0协议的CY68013控制芯片,GPIB协议部分采用NI公司的NAT9914控制芯片。     

离散谱折射率法优化设计MMI型光功分器

采用离散谱折射率法直接对三维脊形自镜像效应(SIE)多模波导的模式特性进行具体分析,并根据模式传播常数偏差分布情况,引入了SIE多模波导长度微小变量用以抵消或部分减弱由各阶模式传播常数偏差引起的相位偏差,设计了一种低自镜像损耗、高均匀度、几乎与偏振无关及深刻蚀SIE多模波导结构的多模干涉(MMI)光功分器。如1×16MMI光功分器TE模的自镜像损耗为0.0451dB,均匀度0.0309dB;对TE模的自镜像损耗为0.0455dB,均匀度为0.0311dB。     

Electronegativity Scaled as a Average Attracting Energy of Valence‐Shell Electrons in a Ground‐State Free Atom

The total capability of an atom attracting valence electrons can be measured by the sum of ionization energies of valence electron in a ground‐state free atom plus its electron affinity called Total Attracting Energy, TAE = Σn_iE_i + EA, where, E_i is the ionization energy of the ith valence‐shell electron in a ground‐state free atom, n_i is the number of valence‐shell electron bearing energy E_i, and EA is the electron affinity. And the electronegativity χ_CL is proportional to the average of TAE, AAE = TAE_av, divided by Σn_i, the number of atomic valence‐shell electrons. χ_CL = 0.1813 TAE_av = 0.1813 AAE = 0.1813 TAE/Σn_i, = 0.1813 (Σn_iE_I + EA)/Σn_i. Further, the atomic valence orbital electronegativity can be also obtained from the TAE value of an atom. Some discussions were made on several special aspects such as scale of rare gases, comparisons with Pauling's and Allen's scales, etc.     

DSP在USB接口中的应用

介绍一种由DSP控制UTMI构成的USB设备通用接口,该系统电路设计简单,配置灵活,设备的USB端口设置可由修改固件而改变,能适用于大部分专用的USB高端设备.详细地叙述了UTMI电路设计以及USB设备的连接检测与传输速度握手过程的固件编程,以及DSP固件编程基本思路.通过设计制作的电路传输速度达到50 MB/s,基本达到USB 2.0的速度极限.     

Binding interactions of EDCs to human estrogen-related receptor gamma deciphered by multiple molecular dynamics and energy calculations

Dichloro-diphenyl-trichloroethane (DDT) analogs, classified as environmental endocrine disrupting compounds (EDCs), have been extensively employed as potent insecticides that can cause endocrine system disruption. However, the precise dynamic structural characteristics and interactions between human estrogen-related receptor gamma (hERRγ) and DDT analogs are not yet fully understood. In this study, we comprehensively investigate the impact of these EDCs (DDT, dichloro-diphenyl-dichloroethane (DDD), 2,2-bis(4-chlorophenyl)ethanol (DDOH), O,P′-DDT (2,4′-DDT), 4,4′-dichlorobenzophenone (DCBP), and 4-hydrotamoxifen (4-OHT) on the structural changes of hERRγ and their interaction mechanisms by employing multiple molecular dynamics (MD) simulations coupled with MM-PBSA and SIE approaches. The consequence manifested that overall structures of these six complexes did not transform markedly, but these compounds can affect the local hERRγ structure, leading to essential changes in interactions with pivotal residues nearby L268, V313, L309, Y326, and F435. And van der Waals interactions are the key to how these EDCs interact with hERRγ. These outcomes contribute to our comprehension the risks of DDT analogues to human health.     

USB2.0 SIE的ASIC设计与实现

简要分析了USB体系结构,参考USB2.0标准构造了USB设备芯片的通信模型.基于这个模型,对USB设备芯片的核心--串行接口引擎(SIE)进行了结构的划分和设计.所设计的SIE在FPGA上通过了硬件验证.     

一种全速USB集线器的设计

介绍了USB集线器的基本功能和原理,提出了一种全速USB集线器的设计方案,重点描述了此方案中关键模块的设计和实现,并简述了MCU固件程序的设计方法.整个方案通过了FPGA验证,可以进一步采用ASIC实现,也可以作为IP嵌入到其它SOC应用中.     

GPIB测试母线在数据传输中电路的应用

介绍了GPIB通用接口母线的特点及其优势,将其应用于单片机USB-GPIB框架的数据传输系统,其中USB部分Cypress公司基于2.0协议的CY68013控制芯片,GPIB协议部分采用NI公司的NAT99l4控制芯片.