高中新教材随堂实验开出率的调查分析及对策

介绍了山东禹城第一中学及其周边学校应用新教材过程中随堂实验的开出情况,分析了随堂实验开出率低的原因,并提出了解决问题的策略.     

Delay Effect on Coherent Transfer of Optical Frequency Based on a Triple-Pass Scheme

We demonstrate a triple-pass scheme for coherent transfer of optical frequency and the delay effect on the fiber phase noise compensation. It is theoretically proved that the delay effect consists of both fiber delay and servo delay. The delay effect confines the servo bandwidth within 1/8 and induces a residual fiber phase noise after noise compensation. For a 25-km-long fiber, the servo bandwidth is found to be around 1 k Hz, and the fiber phase noise is suppressed approaching to the theoretical limitation. The triple-pass scheme enables the simultaneous transfer of optical frequency to multiple remote users. The performance of noise compensator in the triple-pass scheme can achieve a similar level result compared with that in the double-pass scheme.