智能健康住宅监护数据的分析方法

智能健康住宅为缓解人口老龄化的压力和优化医疗资源配置提供了重要手段,其特点是在家庭环境下提供各项生命体征参数监测,并对监护数据自动分析处理.文中提出了以时序建模为基础的智能健康住宅监护数据分析方法.此方法由3个部分构成,包括模型辨识、模型更新以及基于模型的预报区间确定.模型阶数基于最终预报准则确定,使得模型能更好地符合观测数据.基于自适应滤波器算法的模型参数在线更新,能确保模型更好地描述监护数据的动态特性.根据建模结果,作前向30步预报,可确定预报区间.据此,可实现对监护数据中的平稳值、异常值以及状态变化3种特征模式的识别.通过应用PhysioNet中的3组数据集进行实验研究,发现文中方法的预报结果准确,能实现对智能健康住宅中连续监测数据的在线分析.     

Novel Schmitt trigger with wide temperature range

A novel Schmitt trigger circuit, implemented by a reset-set (RS) trigger and two simple distinct inverters, is proposed. Its trigger levels are determined by two Complementary Metal-Oxide-Semiconductor (CMOS) inverters. Contrast with traditional six transistors Schmitt trigger, its temperature and supply voltage characteristics have been analyzed. These two triggers are applied into relaxation oscillator and the result shows that the proposed one in this paper has better performance over wide temperature range, whose temperature coefficient from 0 to 85 °C is 1/5 of the traditional one. Biography: ZOU Zhige (1975–), male, Ph.D. candidate, research direction: analog and mix-signal IC design.     

基于免疫遗传算法的移动机器人轨迹跟踪

为实现移动机器人轨迹的准确跟踪,提出一种基于免疫遗传算法的移动机器人控制器参数整定方法.首先建立移动机器人的结构模型、运动学模型、电机控制系统模型,然后针对所建立的模型,采用一种改进的免疫遗传算法对电机控制系统模型参数进行了整定.该算法在选择下一代的过程中,既考虑了抗原的适应度函数,强调抗体的个人竞争,保证了算法的收敛速度,又引入了抗体浓度概念来体现抗体间的相互交流,从而强化了算法的全局搜索能力,弥补了传统遗传算法搜索能力不足的缺陷.文中最后利用移动机器人的实验平台,进行了带负载下驱动电机的阶跃信号响应和移动机器人运动轨迹的跟踪实验,电机的阶跃信号响应良好,移动机器人也能较好地复现所规划的轨迹.仿真与实验结果表明,所提出的基于免疫遗传算法的机器人轨迹跟踪控制算法有较高的可行性与优越性.     

锚杆锚固结构中导波传播的数值模拟

用理论分析、数值模拟和实验测试的方法研究了自由锚杆和锚固锚杆中的波传播特性.研究结果显示在测试激发波的频率范围内(10～100 kHz),锚杆中传播的波是一个和边界条件相关的导波,不同频率的波在锚杆中传播的速度不同.同时分析了采用有限元模拟锚杆中传播的导波时网格密度对模拟结果精度的影响.模拟体波时一般要求在波传播方向上的N值(一个波长内的单元数)大于20,但模拟杆状结构中的导波传播时N值要大于30,并且径向(垂直波传播方向)的N要求比轴向(波传播方向)N值更大.而且模拟不同频散特性的波需要用不同的N值,也就是说对于同一频率的波,频散越大,所需要的N值亦越大.实验室对自由锚杆和锚固锚杆的测试结果与数值模拟的结果取得了很好的一致性.     

AES中S盒的面积、功耗与安全性分析

研究了高级加密标准(AES)中不同结构S盒实现的面积、功耗与安全性因素,为资源受限和安全性要求高的嵌入式加密应用场合提供了设计参考依据.基于仿真工具和0.25 μm,1.8 V工艺库,完成了包括查找表(LUT)、有限域分解(GF(24))、译码交错编码(DSE)等在内的5种S盒结构设计.基于功耗分析攻击,引入了S盒的功耗比率-相关系数积作为安全性指标.仿真结果表明GF结构S盒具有面积小、安全性高等特点,而DSE结构S盒具有极低功耗特性.     

超立方体网络递归结构的性质及应用

讨论超立方体结构的递归分解结构及性质,运用这种分解可为并行算法分析和设计提供较好的框架和理论基础,特别适用于递归算法的设计和分析。     

The reaction of acenaphthene with nitrobenzene

The reaction of acenaphthene with nitrobenzene was investigated in the presence of AlCl₃. The results showed that the reaction proceeded via carboncation-electrophilic substitution reaction and free radical substitution reaction pathway. The products of acenaphthenyl phenylamine and biacenaphthyl could be synthesized by this reaction. The influence of the amount of AlCl₃ and the temperature on the components of products were also studied in this reaction. Foundation item: Supported by the National Nature Science Foundation of China (No. 29676045) Biography: Wu Lin (1965-), male, Postdictor, research direction: PAHs catalytic conversion and its biologic toxicity.     

Finding global minima with a new dynamical evolutionary algorithm

A new dynamical evolutionary algorithm (DEA) based on the theory of statistical mechanics is presented. This algorithm is very different from the traditional evolutionary algorithm and the two novel features are the unique of selecting strategy and the determination of individuals that are selected to crossover and mutate. We use DEA to solve a lot of global optimization problems that are nonlinear, multimodal and multidimensional and obtain satisfactory results. Foundation item: Supported by the National Natural Science Foundation of China (No. 60133010, NO. 60073043 and No. 700/1042) Biography: Zou Xiu-fen(1996-), female, Ph. D candidate, Associate professor, research direction: evolutionary computing, parallel computing.     

Normalized transfer function for characterizing conversion efficiency and harmonic distortion of all-optical sampling

A novel method for characterizing the nonlinearity of all-optical sampling is proposed based on the normalized transfer function.Simulation results demonstrate the effectiveness of our method.Furthermore,an all-optical sampling experiment is performed to verify our method.Both simulation and experiment show consistency between our method and the measurements.The method only requires normalization and polynomial fitting of the transfer curve,and enables direct expression of the nonlinearity with the coefficients of the normalized transfer function.     

浅谈公路旧桥的加固

作者根据近年对超限运输桥梁及大中型桥梁的加固实践经验,介绍了公路旧桥各组成部分的加固方法和施工措施。