应变测试信号处理电路设计

电阻应变式传感器应用十分广泛。利用电阻应变式传感器作为转换器件进行力的测试是一种常用的测力方法,但是由应变传感器直接输出的信号很微弱,需进行信号调理才能进行数字化处理。本文通过对应变传感器输出信号的分析,设计了一种高精度应变测试放大滤波电路作为微弱应变信号的前置处理电路。电路以高精度仪表放大器AD620与高精度运放OP07作为核心器件。经过实验证明其效果良好,线性失真很低,满足工程运用的要求。     

基于双馈风力发电机的SVPWM死区时间补偿的DSP实现

为了消除PWM脉冲死区时间对双馈风力发电机在低转速时的性能影响,提高风力机在低风速时向电网输送的电能质量.提出了应用DSP56F807对SVPWM死区时间的补偿方法,并详细介绍了其补偿原理以及软件实现.最后通过背靠背测试平台(back-back test bench)验证了该方法的正确性.     

耐湿硫化氢腐蚀07Cr2AlMo无缝钢管研制

对研制的耐湿硫化氢腐蚀 0 7Cr2AlMo无缝钢管进行多项性能试验 ,结果表明 :该钢性能优良 ,各种试验数据均达到设计要求 ,能够满足在湿硫化氢环境下设备的安全使用     

Convoluted Flesh: A Synthetic Approach to Analogue and Digital Architecture

Marcos Cruz and Marjan Colletti advocate their own distinct design approach that is intuitive and blissful in its opulence, evoking the sublime.Here they discuss the potential of opening up ‘new spatial, or material possibilities’ that are liberated from the self-imposed restrictions of their more technologically driven contemporaries. Copyright © 2008 John Wiley & Sons, Ltd.     

Renewable Types and the Urban Plan

The notion of designing according to building type for some might imply constraint, or even a reversion to convention. In Diploma Unit 6 at the AA in London, Christopher Lee and Sam Jacoby have proved typology can be used to liberating effect, producing series that harness ‘the cumulative intelligence’ of type, while ‘surpassing both its idea and its deep structure’. Copyright © 2008 John Wiley & Sons, Ltd.     

D07系列质量流量控制器毛细管堵塞的处理方法

D07系列质量流量控制器被广泛的应用到电子、化工、石油、医药、环保等领域的科研和生产中,当其出现故障时我们要有一个好的解决方法,确保生产正常。     

基于USB2.0的193nm极紫外光强检测系统设计

介绍一种以USB2.0为接口的实时极紫外光强检测系统。光敏二极管输出电压经模拟放大器OP07放大后,再经模数转换器ADS8322转换得到与光强成线性的数字量,用VC++6.0编程对CY7C68013A芯片I/O端口控制实现对转换后的数字量的实时采集,从而实现对193nm光刻照明系统光强的实时检测。     

07Mn2Ni2Mo焊丝在线退火工艺探讨

介绍07Mn2Ni2Mo焊丝在线退火优化工艺。实验内容:(1)在750℃退火温度下,焊丝以2,4,6,8,10 m/min的运行速度进行退火实验;(2)焊丝采用4 m/min的运行速度,选择600,650,700,750,820,900℃进行退火实验。总结出优化退火工艺:退火温度为750℃,焊丝运行速度为4 m/min。退火后焊丝组织为铁素体+细小珠光体,组织已经完全再结晶,塑性指标得到恢复。     

Least tail‐trimmed squares for infinite variance autoregressions

We develop a robust least squares estimator for autoregressions with possibly heavy tailed errors. Robustness to heavy tails is ensured by negligibly trimming the squared error according to extreme values of the error and regressors. Tail‐trimming ensures asymptotic normality and super‐‐convergence with a rate comparable to the highest achieved amongst M‐estimators for stationary data. Moreover, tail‐trimming ensures robustness to heavy tails in both small and large samples. By comparison, existing robust estimators are not as robust in small samples, have a slower rate of convergence when the variance is infinite, or are not asymptotically normal. We present a consistent estimator of the covariance matrix and treat classic inference without knowledge of the rate of convergence. A simulation study demonstrates the sharpness and approximate normality of the estimator, and we apply the estimator to financial returns data. Finally, tail‐trimming can be easily extended beyond least squares estimation for a linear stationary AR model. We discuss extensions to quasi‐maximum likelihood for GARCH, weighted least squares for a possibly non‐stationary random coefficient autoregression, and empirical likelihood for robust confidence region estimation, in each case for models with possibly heavy tailed errors.