| 1. | Development of an alternating message source for the experiment of simulated static electric field tracing
用模拟法描绘静电场实验中交流信号源的研制 |
| 2. | A novel digital watermarking scheme based on synthesis and separation method of direct and alternating signal is proposed in chapter 4
第四章根据直流和交流信号的合成和分离方法,探索了一条频率域鲁棒性水印的新思路。 |
| 3. | The results show that this testing system is fit for the test of dc signals , lower frequency signals and power frequency signals
结果表明，该测试系统不仅适合于直流信号的测试，而且同样适合于低频信号、工频交流信号的测试。 |
| 4. | The instrument is made up of an oscillating detector , which converts the distributed voltage of an insulator to ac signal for further treatment , a singlechip - microcomputer unit and a speaker system
仪器采用振动式探头，把绝缘子的直流电压变成交流信号，处理后，语音直接报出绝缘子的电压值。 |
| 5. | Because frequency - shift signal is a kind of modulation signal , it ' s waveform is two ac sine signal of alternating i . e . upper frequency and lower frequency which was generated by low frequency modulating middle frequency
由于移频信号是一种调频信号，其波形为低频信号调制中心载频信号后产生的低端载频（下边频）和高端载频（上边频）两个交替变化的正弦交流信号。 |
| 6. | A direct signal is founded in host image in dct domain , and the modulated watermark is regarded as alternating signal , so watermark embedding and extracting are similar with direct and alternating signal synthesizing and separating
在载体dct域的中频系数中建立近似直流信号,把水印图像置乱并调制成交流信号,水印的嵌入和检测过程转化为直流和交流信号的合成和分离过程。 |
| 7. | This design is based on the wireless monitoring system of yantai city streetlight , and is mainly about improvement of present system in hardware and software parts . with advanced mcu , this system applies fft to filter high frequency noise
本设计对原有路灯rtu软硬件重新设计，硬件电路从元件选型到电路结构设计都做了重大改进，由于采用高性能微控制器，软件中采用fft计算输入交流信号有效值。 |
| 8. | The three - phase high - frequency ac pulse density modulation ( pdm ) converter , which is proposed in this paper , can efficiently synthesize low - distortion variable frequency variable amplitude low frequency voltage signals from the fixed - frequency voltage of the high frequency link
本文阐述的高频交流脉冲密度调制( pdm )的控制策略能够较容易地将高频交流信号低失真地合成幅值和频率变换的低频信号。 |
| 9. | The original signals are detected by ac sampling algorithm in the protection system , at the same time , power system parameters , such as voltage value , current value are obtained through fourier transform , which accelerates the reaction speed of mcs and improve the reliability of mcs
综合保护系统直接对传感器二次交流信号高速采样，利用傅立叶算法获取所需电压、电流等参数，然后对需控量进行监视、分析、统计和判断，从而使可信度、可靠性得到保障。 |
