基于OPNET的UMTS切换技术的建模与仿真

切换技术是通用移动通信系统(Universal Mobile Telecommunications System,UMTS)的主要关键技术之一,用于保证用户在移动通信网络中的移动性。对目前主要使用的2种切换技术———软切换和硬切换进行了简要介绍,而软切换是码分多址(Code Division Multiple Access,CDMA)系统所特有的。利用OPNET仿真软件搭建了UMTS网络切换模型,对软切换及硬切换技术进行仿真,并对结果进行了比较分析,得出结论,切换技术的优劣会直接影响到系统提供的服务质量。     

3D Knitting for Pneumatic Soft Robotics

Soft robots adapt passively to complex environments due to their inherent compliance, allowing them to interact safely with fragile or irregular objects and traverse uneven terrain. The vast tunability and ubiquity of textiles has enabled new soft robotic capabilities, especially in the field of wearable robots, but existing textile processing techniques (e.g., cut-and-sew, thermal bonding) are limited in terms of rapid, additive, accessible, and waste-free manufacturing. While 3D knitting has the potential to address these limitations, an incomplete understanding of the impact of structure and material on knit-scale mechanical properties and macro-scale device performance has precluded the widespread adoption of knitted robots. In this work, the roles of knit structure and yarn material properties on textile mechanics spanning three regimes–unfolding, geometric rearrangement, and yarn stretching–are elucidated and shown to be tailorable across unique knit architectures and yarn materials. Based on this understanding, 3D knit soft actuators for extension, contraction, and bending are constructed. Combining these actuation primitives enables the monolithic fabrication of entire soft grippers and robots in a single-step additive manufacturing procedure suitable for a variety of applications. This approach represents a first step in seamlessly “printing” conformal, low-cost, customizable textile-based soft robots on-demand.     

超薄栅氧化层中的软击穿的击穿机理和击穿模型

软击穿是与氧化层质量密切相关的一种新的击穿形式。当氧化层厚度小于5nm时,软击穿效应显著,是超薄栅氧化层的主要失效机理。通过对国外软击穿研究状况的分析,对超薄栅氧化层中软击穿的失效模型和机理进行了综述。     

黄冈电信中兴固网软交换SS设备1：0容灾机制的浅析

从中兴固网软交换SS设备1：0异地容灾切换机制着手,重点分析了中兴软交换双归属设备间数据同步机制以及在数据配置上来实现业务接管的可行性,希望能为软交换网络应急保障处置措施提供一种解决办法和思路。     

基于前向多层神经网络的分组码译码器设计

把最大相关译码与神经网络神经元的内积特性及吸引域有机地联系起来,连接权决定译码码字,阈值设定决定神经元的纠错范围,从而形成一种可用于硬判决及软判决译码的神经译码器,并在理论上证明了此译码器可在ＤＭＣ信道的纠错能力范围内实现零错误概率硬判决译码,也可实现与最小欧几里德距离译码相当的软判决译码,并能在检错范围内检错。     

宽带网络SOQPSK突发波形

空基网络通信应用中,采用恒包络波形体制可以降低设备特别是功放的复杂度,因此高效的成形偏移四相相移键控(SOQPSK)信号非常适合于空基网络。但是机载通信中多普勒频移较大,在低信噪比和短突发条件下,SOQPSK相干接收机必须有精确的载波频率和相位同步才能获得较好的性能。针对低信噪比和短突发场景,提出了基于Turbo乘积码（TPC）编码的扩频SOQPSK宽带网络波形,并设计了导频与数据帧结构,利用译码器输出的软信息来改善载波同步的性能,通过迭代操作和联合解调、解扩,增强了系统的同步性能。仿真结果表明,在误码率为10-6时所需Eb/N0为3.65 dB,达到了波形设计指标要求。     

An improved two-switch flyback converter with regenerative clamping

A novel soft-switching two-switch flyback converter is proposed in this article. This converter is composed of two active power switches, a flyback transformer and two passive regenerative clamping circuits. The proposed converter has the advantages of a low-cost circuit configuration, a simple control scheme, high efficiency, and a wide operating range. The circuit topology, analysis, design considerations and experimental results of the new flyback converter are presented.     

线性分组码的神经网络译码

介绍了神经网络与线性分组码之间的关系，并在文献[1]的基础上证明了软判决译码与求解能量函数最大值之间的等价性，然后以(7，4，3)汉明码为例介绍了神经网络在循环码硬判决、软判决译码中的应用。     

用于软X射线光刻的等离子体源及干涉诊断分析

阐述了等离子体的产生机理和影响软 Ｘ 射线产生的因素,利用产生软 ｘ 射线的实验系统,分析了软ｘ 射线转换效率与原子数的关系及其空间相干性。给出了等离子体的干涉诊断方法及几个重要的结论。     

Rewritable Electrically Controllable Liquid Crystal Actuators

Conductive structures determine the functions and actuation modes of electrically responsive soft actuators. The rewritability of conductive structures is highly desirable but has not been realized in electro-driven actuators. Typically, once conductive pathways are established, they can hardly be modified; thus, the function of the actuator is permanently fixed. In this study, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is developed as a rewritable conductive coating for actuators composed of liquid crystalline elastomers (LCEs). This enables reconfigurable, adaptive, and precisely controllable electro-driven motions and the repeated use of the same actuator for various purposes without disposal. Moreover, different PEDOT:PSS layers can be coated onto different regions, thus enabling the assembly of different actuation behaviors in a monolithic actuator under a single input voltage. Unlike all previously reported soft actuators that respond to electricity and light, opposite shape changes in an actuator with a series circuit can be performed under these two stimuli. Furthermore, when combining LCEs with dynamic covalent bonds, the PEDOT:PSS-coated LCE (PEDOT:PSS-LCE) actuator can be reprogrammed based on two different mechanisms: rewriting the conductive PEDOT:PSS patterns and re-aligning the LCEs. This versatile method can be adapted to other types of actuators.