16信道0.35μmCMOS/VCSEL光发射模块

研究了垂直腔面发射激光器 (VCSEL)及其列阵器件的光谱特性、调制特性、高频特性及与微电子电路的兼容性 ,将 1× 16的VCSEL与CMOS专用集成电路进行多芯片组装 (MCM ) ,混合集成为 16信道VCSEL光发射功能模块 .测试过程中 ,功能模块的光电特性及其均匀性良好 ,测量的 - 3dB频带宽度大于 2GHz.     

An optimization model for placement of wavelength converters to minimize blocking probability in WDM networks

The introduction of wavelength converters in wavelength division multiplexing (WDM) networks can reduce the blocking probabilities of calls. In this paper, we study the problem of placing a given number of converters in a general topology WDM network such that the overall system blocking probability is minimized. The original contributions of this work are the following: 1) formulation of success probability in a network as a polynomial function of the locations of converters; 2) proposal of an optimization model of the converter placement problem as the minimization of a polynomial function of 0-1 variables under a linear constraint, so that standard optimization tools can be employed to solve the problem; and 3) design of a search algorithm that can efficiently find the optimal solution to the converter placement problem. Experiments have been conducted to demonstrate the effectiveness of the proposed model and the efficiency of the algorithm.     

实时数据库及在电厂集成自动化系统中的应用

从控制信息系统集成角度出发 ,在简述火力发电厂自动化发展的基本现状和分析比较实时数据库与关系数据库异同的基础上 ,结合萧山电厂集成自动化系统项目 ,总结了实时数据库工程应用的关键技术 ,最后提出了实时数据库的选型原则。     

碳纳米管的大面积合成及磁性(英文)

通过溶胶凝胶法和氢气还原法制备出Co纳米颗粒并以此作为催化剂材料,通过催化裂解苯的方法,实现了较低温度(460℃)下在Co纳米颗粒表面上合成碳纳米管。采用X射线衍射、激光喇曼光谱、场发射扫描电镜、透射电子显微镜和振动样品磁强计对所合成的碳纳米材料进行了表征。通过优化实验参数,可制备出最大产率和纯度分别为约50和98.02%(质量分数)的碳纳米管。由于铁磁性Co纳米颗粒的进入,使得整个复合物表现出比较好的磁性能。和以往以苯作为碳源合成碳纳米材料相比,此合成方案简单、成本低,且对环境无任何危害,非常适用于磁性碳纳米复合物的批量合成。     

天线阵结构对非视距室内MIMO信道容量的影响

采用2维射线跟踪法分析了非视距室内环境中天线间隔、天线阵形对MIMO系统容量和互补累积分布函数(CCDF)的影响。结果表明随着天线间隔减小,MIMO系统容量降低。10%中断容量表明,天线间隔相同时,有独立同分布瑞利信道容量大于线性阵容量大于方阵容量或者圆形阵容量的关系。当天线间隔大于等于3 时,不同天线阵列阵形对容量影响非常小,此时i.i.d.瑞利信道理论容量几乎全部实现。当天线间隔小于等于1 时,天线阵列阵形对容量影响较大,矩形阵和圆形阵MIMO系统容量相差较小,但都显著小于线性阵列系统容量。在非视距的室内环境中,要实现最大的MIMO容量增益,设计天线阵列时应该对天线间隔和阵列阵形综合考虑。     

分散剂在sol-gel法制备PZT粉体中的应用

采用sol-gel法制备了PZT纳米粉体。针对硝酸铅会从干凝胶中析出的问题,分析了硝酸铅的析出原因,采取在溶胶中加入柠檬酸三铵作为分散剂来消除硝酸铅的偏析。实验结果表明:当柠檬酸三铵的加入量为醋酸铅的2.5%(摩尔分数)时,能得到粒度较为均匀,组成与计算配方一致的PZT纳米粉体。     

An efficient anonymous communication protocol for wireless sensor networks

Anonymous communication is very important for many wireless sensor networks, because it can be used to hide the identity of important nodes, such as the base station and a source node. In sensor networks, anonymous communication includes several important aspects, such as source anonymity, communication relationship anonymity, and base station anonymity. Existing sensor network anonymous schemes either cannot achieve all the anonymities or have large computation, storage, and communication overheads. In this paper, we propose an efficient anonymous communication protocol for sensor networks that can achieve all the anonymities while having small overheads on computation, storage, and communication. We compare our anonymous communication protocol with several existing schemes, and the results show that our protocol provides strong anonymity protection and has low overheads. Copyright © 2011 John Wiley & Sons, Ltd.     

分布式移动通信系统中基于多普勒测速与卡尔曼滤波的动态定位算法

该文提出了一种分布式移动通信系统中的动态定位算法,算法中首先通过远端天线单元(RAU)测量移动台(MS)的多普勒频偏,将其变换为MS到各RAU方向的径向速度,建立状态方程和观测方程,然后采用扩展卡尔曼滤波法估计移动台的当前位置,并通过逐次迭代即可实现MS运动轨迹的动态估计。因为卡尔曼滤波法的引入,该算法有效地降低了当前估计误差对后续时刻估计值的影响,从而可获得较高的定位精度。     

A Multifunctional Pro‐Healing Zwitterionic Hydrogel for Simultaneous Optical Monitoring of pH and Glucose in Diabetic Wound Treatment

Diabetic ulcer is the most common kind of chronic wound worldwide. Though great efforts have been devoted, diabetic ulcer still remains as a challenge that requires constant monitoring and management. In this work, a multifunctional zwitterionic hydrogel is developed to simultaneously detect two fluctuant wound parameters, pH and glucose level, to monitor the diabetic wound status. A pH indicator dye (phenol red) and two glucose sensing enzymes, glucose oxidase (GOx) and horseradish peroxidase (HRP), are encapsulated in the anti‐biofouling and biocompatible zwitterionic poly‐carboxybetaine (PCB) hydrogel matrix. The visible images are collected by a smartphone and transformed into RGB signals to quantify the wound parameters. Results show that the activity and stability of both two enzymes are improved within PCB hydrogel, and the K_cat/K_m value of PCB‐HRP is ≈5.5 fold of free HRP in artificial wound exudate. This novel wound dressing can successfully monitor the pH range of 4–8 and glucose level of 0.1–10 × 10^?3 m . Meanwhile, it also provides a moist healing environment that can promote diabetic wound healing. This multifunctional wound dressing may open vistas in chronic wound management and guide the diabetes treatment in clinical applications.     

亮暗衬线法校正邻近效应及其实验研究

光学光刻中的邻近效应校正是实现亚微米光刻的必要手段。作者基于波前加工的思想,提出亚分辨亮暗衬线结合辅助线条实现邻近效应校正的方法,分析了其校正机理,采用这种新方法,在可加工0.7μm光刻图形的I线投影曝光装置上加工出了0.5μm的光刻图形,取得了较好的实验结果,并与其它邻近效应的校正方法进行了比较。