摘要：为了解决电压模拟信号的远程传输和光隔离问题，利用AD7740构成VFC，再将信号通过HFBR1521转换为光信号通过光纤进行传输，利用HFBR2521接收光信号，通过AD650构成fvc，从而实现电压信号的远程安全传输．信号发送端采用AD7740，在保证V—F转换线性度的同时提高了性价比，接收端采用AD650从而保证了F—V转换线性度．通过光纤传输信号一方面解决了电隔离问题。另一方面可以有效降低环境干扰，实现远程传输．根据上述原理设计了性能良好、结构简单和精确度较高的信号转换及传输电路．该电路创新之处在于实现了模拟信号的远程传输并保证了良好的准确性，同时实现了电隔离．实验证明设计电路线性度良好，远端接收端能够精确再现0—5V模拟电压，因此设计电路能够满足多数场合下电压控制信号远程传输需要．

摘要：基于PWLL结构的占空比矫正电路虽然克服了传统占空比矫正电路输出时钟上升沿在占空比矫正过程中发生变化的缺点，但其核心电路——频率电压变换电路不能工作在100MHz以上的频率范围，并且随着工作频率的升高，调整范围会变小。采用pullpush电荷泵代替频率电压变换电路，设计了一个工作在200MHz的占空比矫正电路，HSPICE仿真结果表明其调整范围为30％-70％，占空比变化在1个ps以下，达到了设计要求。

摘要：高升的化石燃料价格与对全球变暖的恐惧使人们对可再生能源的兴趣大增,并使得相关支持与演示仪表也受到关注。

摘要：The rapidity of progression of amyotrophic lateral sclerosis (ALS) to death or respiratory failure impacts patients, clinicians, and clinical investigators. This study compared the abilities of various pulmonary function tests to predict tracheostomy-free survival. We evaluated 95 ALS patients by determining upright and supine forced vital capacity (fvc), maximal inspiratory (MIP) and expiratory (MEP) pressures, arterial partial pressure of carbon dioxide (PaCO2), and tran sdiaphragmatic sniff pressures (Pdi-sniff). Tracheostomy-free survival time was measured from the date of spirometry. Supine fvc, upright fvc,MIP,MEP, and Pdi-sniff were significantly associated with tracheostomy-free survival after controlling for non-pulmonary factors, whereas PaCO2 was not. A normal supine fvc, MIP, or MEP was highly predictive for one-year survival. These tests are well suited to predict survival for trial enrollment and patient counseling. Supine fvc’s simplicity of use and availability to ALS investigators makes it a particularly attractive predictor of one-year survival in ALS.