轻型鱼雷换速系统特性研究

为了提高轻型鱼雷动力系统换速的稳定性,避免高速向低速转换时燃烧室压力过高而引发爆炸以及低速向高速转换时燃料供应中断或燃烧室压力过低而熄火,该文根据压力平衡原理,提出了延长换速过渡过程时间的解决方案,分析了其工作原理,建立了相应的数学模型,通过动态仿真和动态特性试验证实,该方案对延长换速过渡时间有明显的效果,并可大大减小换速过程中的压力变化的斜率,这对换速过程动力系统的工作稳定性和可靠性有重要意义。     

PWM驱动系统中的对称功率滤波器设计

针对PWM驱动系统中存在的高频开关噪声问题,设计了一种新型的对称功率滤波器。根据等效阻抗原理,得到滤波网络的传递特性,并对滤波电路进行了频域和时域仿真分析。经过实验验证,高频开关噪声被抑制在允许范围内,不影响数字化控制回路的性能。     

Low Capture Switching Activity Test Generation for Reducing IR-Drop in At-Speed Scan Testing

At-speed scan testing, based on ATPG and ATE, is indispensable to guarantee timing-related test quality in the DSM era. However, at-speed scan testing may incur yield loss due to excessive IR-drop caused by high test (shift & capture) switching activity. This paper discusses the mechanism of circuit malfunction due to IR-drop, and summarizes general approaches to reducing switching activity, by which highlights the problem of current solutions, i.e. only reducing switching activity for one capture while the widely used at-speed scan testing based on the launch-off-capture scheme uses two captures. This paper then proposes a novel X-filling method, called double-capture (DC) X-filling, for generating test vectors with low and balanced capture switching activity for two captures. Applicable to dynamic & static compaction in any ATPG system, DC X-filling can reduce IR-drop, and thus yield loss, without any circuit/clock modification, timing/circuit overhead, fault coverage loss, and additional design effort.

基于消息同步的双机热备份系统在移动业务交换中心的应用

本文分析了当前双机热备份系统设计中存在的问题,提出了一种基于消息同步的双机热备份系统的实现方法,并将之应用于移动业务交换中心的设计中.该方法可以实现容错对上层业务的透明性和容错结构的动态性.     

分组交换网络调度算法概述

为了合理利用网络资源,提高网络吞吐率,降低通信时延,需要采取有效的调度算法实现输入端和输出端的匹配.基于VOQ的输入排队交换结构是当前分组交换网络最常用的结构.本文介绍了几种基于VOQ的调度算法:用于单级crossbar的PIM、iRRM和iSLIP算法,以及适用于三级Clos网络的RD和CDDR算法.对每种算法,介绍其基本原理和性能,以及与其他算法的区别.     

Wideband Capon Beamforming for a Planar Phased Radar Array with Antenna Switching

A wideband beamforming algorithm for estimating the azimuth angle, elevation angle, velocity, and range using a planar phased radar array with antenna switching is proposed. It uses the time-variant steering vector model. Simulation results illustrating the performance of the proposed beamformer are presented.     

固态雷达发射机双监控系统

对发射机双监控系统的构成和工作原理进行了介绍 ,通过设计举例对固态雷达发射机双监控系统的系统设计和双机切换的工作流程进行了具体阐述     

A novel online wavelength assignment algorithm in wavelength-convertible multi-granular optical networks

As industrial technology gets more mature, a single fiber can offer more and more wavelengths. However, it also results in a large amount of switching ports at optical cross-connects (OXCs). Certainly, it is expected that higher and higher complexity is inevitable to control and manage such large OXCs. In this paper, we study the dynamic wavelength assignment problem in waveband switching (WBS) networks composed of multi-granular OXCs (MG-OXCs). Moreover, in order to relax the wavelength continuity constraint on lightpath establishments, each MG-OXC node is equipped with a certain number of converters. To efficiently minimize the extra port consumption and utilize wavelength converters, we proposed an online wavelength assignment algorithm named Least Weighted Configuration Cost (LWCC). For a new request, LWCC first adopts fixed routing and then exploits the layered-graph approach and a new cost function for edge weight assignment to determine adequate wavelength(s). The performance metrics of interest include both blocking performance and converter utilization. Numerical results show that LWCC is superior in waveband grouping and therefore results in significant performance gain in terms of blocking probability.

CDMA系统中基于公平性考虑的博弈功率控制算法

为解决CDMA系统中各用户与基站间距离的远近公平问题,提出了一种基于公平性考虑的非合作博弈功率控制算法。该算法综合考虑用户路径增益与发射功率等,设计了一种新的且存在唯一纳什均衡的代价函数,进而能够改善系统中的远近公平问题。仿真结果表明,与传统的功率控制算法相比,提出的功率控制算法具有用户发射功率降低,而且用户获得的SIR是远近公平的,并且用户获得的收益也是远近公平的优势。系统的远近公平问题得到了很好的改善。     

Unipolar resistive switching of Au+-implanted ZrO2 films

The resistive switching characteristics of Au+-implanted ZrO2 films are investigated.The Au/Cr/Au+-implanted-ZrO2/n+-Si sandwiched structure exhibits reproducible unipolar resistive switching behavior.After 200 write-read-erase-read cycles,the resistance ratio between the high and low resistance states is more than 180 at a readout bias of 0.7 V. Additionally,the Au/Cr/Au+-implanted-ZrO2/n+-Si structure shows good retention characteristics and nearly 100% device yield.The unipolar resistive switching behavior is due to changes in the film conductivity related to the formation and rupture of conducting filamentary paths,which consist of implanted Auions.