On optimizing system energy of voltage–frequency island based 3-D multi-core SoCs under thermal constraints

Three dimensional (3-D) multi-core SoC has been recognized as a promising solution for implementing complex applications with lower system energy. Recently, voltage–frequency island (VFI)-based design paradigm was widely adopted for energy optimization. However, the existing work commonly targeted 2-D platform, which cannot handle the exacerbated thermal issues and the increased solution space from 3-D integration. In this paper, we propose an optimization framework targeting VFI-based 3-D multi-core SoCs to minimize system energy meanwhile still meeting task deadline and thermal constraints. Our framework conducts at an earlier design phase in which designers have the freedom to determine the core stacks and map them into the hardware platform. Besides energy-aware task scheduling, we also conduct core stacking and task adjusting to balance the powers across the chip for thermal optimization. Moreover, by treating each core stack as a unity, the complicated problem of core mapping and VFI partitioning in 3-D platform can be simplified as a 2-D one. Experimental results demonstrate that on average our framework can achieve an energy reduction of 15.8% over the prior thermal balancing algorithm [17] (X. Zhou, J. Yang, Y. Xu, et al. Thermal-aware task scheduling for 3D multicore processors, IEEE Trans. Parallel Distrib. Syst. (TPDS), 21(1) (2010), 60–71.). Moreover, on average a reduction of 4.8 °C in peak temperature is achieved by our framework, compared with the state-of-the-art energy optimization scheme [8] (U.Y. Ogras, R. Marculescu, P. Choudhary, et al. Voltage–frequency island partitioning for GALS-based networks-on-chip, in: ACM/IEEE Design Automation Conference (DAC), 2007, pp. 110–115.).     

电子吊舱在现代雷达抗干扰测试中的设计应用

电子吊舱在外军的电子战装备中有着举足轻重的地位，在几次局部战争中发挥了巨大的作用。文中介绍了电子吊舱的设计及其应用，首先介绍了电子吊舱的分类及其功能，介绍了电子吊舱的系统组成及设计重点，然后分析了电子吊舱收发隔离及在压制干扰情况下对雷达的干扰效能，最后给出了典型的试验结果。     

“数字电子技术”研讨型课程探索

本文提出将"数字电子技术"课程作为研讨型课程开设的思路,将课程中仿真软件的教学部分以研讨课的形式开设,并对研讨型课程的优势和课程开设的关键问题进行了分析,提出教师的引导和研讨模块的设计是研讨课程成功的关键因素;本文还从教学进度安排和教学过程设计及成绩考核模式等方面进行了教学实践,总结了实践效果,并提出将实验教学和课程设计进行研讨的新思路。     

基于混合离散粒子群算法的MPRM电路延时和面积综合优化

Polarity optimization for mixed polarity Reed-Muller(MPRM) circuits is a combinatorial issue.Based on the study on discrete particle swarm optimization(DPSO) and mixed polarity,the corresponding relation between particle and mixed polarity is established,and the delay-area trade-off of large-scale MPRM circuits is proposed. Firstly,mutation operation and elitist strategy in genetic algorithm are incorporated into DPSO to further develop a hybrid DPSO(HDPSO).Then the best polarity for delay and area trade-off is searched for large-scale MPRM circuits by combining the HDPSO and a delay estimation model.Finally,the proposed algorithm is testified by MCNC Benchmarks.Experimental results show that HDPSO achieves a better convergence than DPSO in terms of search capability for large-scale MPRM circuits.     

浅谈B2C环境下提高电子忠诚的方法

随着互联网的发展,中国网络购物市场蓬勃发展。B2C市场中,各大电子商务企业的竞争已经到了白热化阶段。吸引并挽留顾客是网商获取利益的关键也是企业长远发展的必备条件。因此,提高顾客的电子忠诚已经成了网商的首要任务。本文基于B2C环境,提出提高电子忠诚的方法,为电子商务市场的长远发展提出建议。     

南京电视台播控中心机房供配电系统改造

针对国内电视播出机构因供电系统故障严重影响电视节目安全播出的现状和总局《广播电视安全播出管理规定》（下简称：总局令第62号）,南京电视台电视播出部对播控中心机房供配电系统进行了维护与改造,确保“播出系统和总控系统的主备播出设备、双电源播出设备应分别接入不同的供电回路”,UPS负载有效减低,供电隐患得以消除,用电安全等级符合总局“二级保障电视中心”要求。     

单层ITO薄膜在ENZ波段增强非线性光学效应的研究

在玻璃基底上镀35 nm厚的ITO薄膜,通过椭偏仪测量ITO薄膜的线性介电常数.由于ITO具有高掺杂浓度,因此其介电常数可以用Drude模型来进行量化计算,得到其介电常数近零(ENZ)波长约为λ=1 100 nm.借助双温模型计算电子温度和晶格温度随时间的变化,根据电子温度的升高计算等离子体频率的变化,将其带入Drude模型中,可以得到一个新的介电常数,最后可以通过计算折射率的变化,从而求出非线性折射率n2.计算结果表明,在ENZ波长入射时,可以得到最大非线性折射率n2=4.66×10-15 m2/W.因此,实验中选取的材料可在低功率光照下得到显著的折射率变化,可望应用于全光存储、全光开关等纳米光子器件的设计.     

Atomistic Origin of the Enhanced Crystallization Speed and n‐Type Conductivity in Bi‐doped Ge‐Sb‐Te Phase‐Change Materials

Phase‐change alloys are the functional materials at the heart of an emerging digital‐storage technology. The GeTe‐Sb₂Te₃ pseudo‐binary systems, in particular the composition Ge₂Sb₂Te₅ (GST), are one of a handful of materials which meet the unique requirements of a stable amorphous phase, rapid amorphous‐to‐crystalline phase transition, and significant contrasts in optical and electrical properties between material states. The properties of GST can be optimized by doping with p‐block elements, of which Bi has interesting effects on the crystallization kinetics and electrical properties. A comprehensive simulational study of Bi‐doped GST is carried out, looking at trends in behavior and properties as a function of dopant concentration. The results reveal how Bi integrates into the host matrix, and provide insight into its enhancement of the crystallization speed. A straightforward explanation is proposed for the reversal of the charge‐carrier sign beyond a critical doping threshold. The effect of Bi on the optical properties of GST is also investigated. The microscopic insight from this study may assist in the future selection of dopants to optimize the phase‐change properties of GST, and also of other PCMs, and the general methods employed in this work should be applicable to the study of related materials, for example, doped chalcogenide glasses.     

Direct Growth of Nanographene on Silicon with Thin Oxide Layer for High‐Performance Nanographene‐Oxide‐Silicon Diodes

Graphene‐silicon based configurations are attracting great attention for their potential application as electronics and optoelectronics. For their practical use, it is still limited by the configuration fabrication process. In this paper, a catalyst‐free method is reported to directly grow nanographene on silicon covered with a thin oxide layer to form nanographene‐oxide‐silicon configurations. Compared with previously reported nanographene‐silicon Schottky junctions, the nanographene‐oxide‐silicon structures exhibit a high performance on electronic and photovoltaic properties. The reverse leakage current of the nanographene‐oxide‐silicon is suppressed from over 10^?5 A down to 10^?8 A and the rectifier ratio is greatly enhanced from less than 5 up to 10³. The photovoltage is enhanced over 50 times. The nanographene‐oxide‐silicon structures exhibit especially ultrasensitive to weak light at a photovoltage working mode, which exceeds up to 10⁶ V/W at the light power of 0.025 μW. Due to the source material for nanographene is photoresist and the fabrication process is mainly based on the current‐used photolithography and silicon technique, the developed nanographene‐oxide‐silicon structures are very easy for device fabrication, integration, and miniaturization, and could be a promising way to produce metal‐free graphene‐silicon based electronics and optoelectronics for commercial use.     

RC正弦波振荡电路的教学设计

RC正弦波振荡电路是学生在学习"模拟电子技术基础"课程时,普遍反映比较抽象枯燥的教学内容。本文针对这部分内容,围绕着如何激发学生的学习兴趣进行精心设计,从知识的引入展开,再到知识的深化,采用问题链和仿真手段,逐步推进,取得了较好的教学效果。