二维寄生电容参数的对偶离散几何法提取

寄生电容参数提取是集成电路领域的关键课题,也是典型的静电场问题之一。通过研究电磁场对偶离散几何法, 探讨在二维非结构化网格离散空间上相应的寄生电容提取算法, 其中重点考察其对偶特性以及能量互补特性。基于该特性,同时采用对偶的两种方法能够有效地消除网格离散带来的误差,比采用单一方法更快地逼近真实解,从而可发展出静电场能量快速算法。并从理论与实例两方面将其与对偶有限元法实施分析对比。离散几何法采用对偶两套网格上的标量电势作为未知量,具有简单的形式与良好的精度,有望成为相关领域的一种主流方法。     

Crystallization kinetics of Sn40Se60 thin films for phase change memory applications

The crystallization kinetics of Sn₄₀Se₆₀ thin films has been successfully investigated using sheet resistance versus temperature measurements. Thermal evaporation was used to deposit the films on ordinary glass substrates. The crystallization temperature for Sn₄₀Se₆₀ thin film was found to be 156.6 ± 0.3 ℃. In the as-deposited state, the sheet resistance was found to be 195 MΩ, this value declined to 1560 Ω/口 upon annealing. The value of activation energy obtained from the Kissinger plot was 0.62 ± 0.07 eV. From the results obtained, Sn₄₀Se₆₀ is a promising alloy for PCM application because of its high electrical contrast, high crystallization temperature, and relatively high activation energy.     

基于改进型双门限语音端点检测算法的研究

语音端点检测是语音信号处理过程中的一个重要步骤,其检测准确性直接影响语音信号处理的速度和效果.传统的基于双门限法语言检测技术,在语音处于纯语音情况下判断语音端点较准确,但在语音处于噪声情况下,尤其是低信噪比的情况下,端点识别率很低,出错率很高.基于提高此方法识别率的目的,采用调整阈值个数,平滑滤波,引入语音结束最小长度的方法对其进行改进,通过了Matlab仿真实验,得出了较好的语音端点检测准确率.     

基于北斗卫星通信的偏远地区用电信息采集

目前电力公司在进行各类用户的用电数据采集上,通信方式主要有手机通信网络、光纤网络、电力微波网络等.本文针对广大人烟稀少山区、牧区中不具备以上通信条件的光伏电站、水电站和居民用户,采用北斗卫星导航系统中的短报文服务为通信通道,通过研发一种小型数据交换装置,在台变现场和电力公司主站系统前端同时部署,在不改变已投运设备和系统的前提下,透明的嵌入北斗通信链路,解决偏远地区的用电信息采集难题.     

水情自动测报系统遥测站低功耗设计研究

针对水情自动测报系统运行环境和特点,分析了影响遥测站功耗的主要因素,详细阐述了器件选型、电源控制、远程通信、软件编程等关键环节进行低功耗设计的策略与实现方法。据此设计的数据采集器在现场得到广泛运用,验证了本方法的有效性和实用性。     

高端路由器主备同步技术的研究

高端路由器设备通常采用主备倒换来延长系统的可靠运行时间,而主备数据同步是实现主备倒换的关键技术。针对传统主备同步技术可靠性低,同步速率低的问题,提出了一种新的主备数据同步解决方案。新的主备同步方案使用了可靠的主备数据同步通道;提出给同步数据分类,并采用合适的方法同步。经实验验证,该技术方案应用在高端路由器上,提高了主备同步速率与可靠性,从而提高了系统性能,同时模块化的设计,具有很好的通用性,实现简单,实用性高。     

Analysis of the Stakeholder Engagement in the Deployment of Renewables and Smart Grid Technologies

The implementation of higher shares of renewables in a global energy mix has to be accompanied by simultaneous deployment of enabling smart grid technologies (SGTs). This combination will inevitably lead to a revolutionary change in a conventional energy system, particularly, the shifting role of consumers to prosumers. But resistance may arise from such a dramatic shift, since it is associated with high uncertainty in conjunction with increasing responsibilities of all stakeholders, the urgent need of effective control, and the development of a process. To ensure the positive influence, coherent actions of all players, and appropriate treatment of the spots of resistance, the analysis of the interplay between key stakeholders has been done. The paper introduces the framework for stakeholders' analysis, applies it on the European Union (EU) example, and provides recommendations to reduce the resistance of SGTs deployment.     

Performance Evaluation of Compressed Air Energy Storage Using TRNSYS

The appreciable economic growth in some of the developing countries like India in the recent years, towards providing energy security causes large environmental impact. Renewable Energy (RE) is being seen as one of the important means to meet the growing power needs of the economy while enhancing energy security and providing opportunities for mitigating greenhouse gas emissions. However, RE sources are highly intermittent in nature. The variability of these sources has led to concerns regarding the reliability of an electric grid that derives a large fraction of its energy from these sources as well as the cost of reliably integrating large amounts of variable generation into the electric grid. Hence at this juncture, it is necessary to explore the benefits of suitable Energy storage technologies. Compressed air energy storage (CAES) is a commercial, utility-scale technology that provides long-duration energy storage with fast ramp rates and good part-load operation. It is a promising storage technology for balancing the large-scale penetration of renewable energies, such as wind and solar power, into electric grids. Considering the potential of CAES storage, the present work, a thermodynamic model is developed with suitable assumptions and the simulation analysis is performed using transient system simulation (TRNSYS) v17 software. The system performance is compared by considering the recovery during the heat of compression using a thermal storage system and without considering the heat recovery. The overall turnaround efficiency of the system without considering the thermal energy storage (TES) system is 57% and with TES system the efficiency is increased to 70%.     

基于无噪后验错误矢量信号能量的变正则因子仿射投影算法

变正则因子技术是提高仿射投影自适应算法性能的重要方法之一.由于环境噪声的影响,现有的变正则因子自适应算法收敛速度较慢且稳态误差较大,各种测量、评估误差的存在进一步恶化了算法性能.为提高自适应算法的跟踪性能,本文在分析无噪先验错误矢量、无噪后验错误矢量和额外均方错误间关系的基础上,提出通过最小化无噪后验错误矢量信号能量来推导自适应变正则因子表达式的方法.在实践应用中,该方法利用了测量噪声的统计方差特性,并提出一种更加光滑且更加容易控制的指数缩放因子评估方法.系统辨识的仿真结果表明本文方法与传统的变正则因子方法以及变步长方法相比有更快的收敛速度与更低的稳态误差.     

最大化最小能耗概率的移动Sink无线传感器网络数据收集方法

在基于移动sink传感器网络中,传感器节点能量受限,数据收集的能耗问题一直是研究的热点.通过建立最大化最小能耗概率模型,提出一种最大化最小能耗概率(Maximizing Minimum Probability of Energy Consumption,MMPEC)数据收集方法.MMPEC对网络中子节点与汇聚节点之间的路径长度进行分布式优化,使得整个网络的能耗达到最低的概率最大化.仿真结果表明,MMPEC在能耗方面优于同类基于移动sink的WSN分层数据收集方法.