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- Much as bats do, robots send out ultrasonic signals. 机器人就象蝙蝠那样地发出超声波讯号。
- The ultrasonic signals are excited by laser and received by polyvinylindene fluoride (PVDF) transducer. 超声信号由激光激发，并且由聚偏二氟乙烯(PVDF)传感器接收。
- An ultrasonic signal that’s undetectable to the human ear will scare off the varmint from up to 65 feet away. 一个人耳不能察觉的超声波信号会吓跑65多英尺以外的淘气动物。
- Simulation results indicate that the method can detect FHR from the Doppler ultrasonic signals and solve the problems of frequency doubling and halving. 仿真结果表明,该方法能准确地从超声多谱勒信号中提取胎心率,成功地解决了现有的胎心监护仪存在的加倍、减半的问题。
- A new denoising method for ultrasonic signal based on blind source separation(BSS) is proposed. 提出一种新的基于盲源分离的超声信号去噪方法。
- The system with signal peak voltage holding, A/D converter, microprocessor, D/Aconverter and voltage adjustment was introduced to realize the ultrasonic signal AGC. （3）采用自动增益控制，即信号的峰值电压经A/D变为数字信号送给单片机，再通过D/A和电压调节电路调节增益控制电压，实现测量信号的自动增益控制。
- The ultrasonic defect echo of a austenite stainless steel with coarse grainswas acqiuired and processed using a developed computerized ultrasonic signal analysissystem. 采用计算机化超声信号分析系统，对奥氏体不锈钢粗晶材料缺陷的超声回波信号进行采集和加工。
- Wavelet packet decomposition (WPD) was applied to feature extraction of ultrasonic signals, chaos-genetic optimization to eliminate redundant and irrelevant features and support vector machine to perform the identification task. 该系统采用小波包分解提取超声信号的特征,采用混沌遗传算法来消除冗余和不相关的特征,并采用支持向量机(SVM)来对缺陷进行识别。 为了验证系统的有效性,在实验室内作了大量的超声检测实验。
- It made use of the signal automatic gain control (AGC) and complex logical control to realize the precise measurement of the ultrasonic signal, and made use of the logical analytical method to realize double frequency and 160 MHz frequency of the counter. 利用超声波信号的自动增益控制 (AGC)和复杂的逻辑控制实现信号的精确测量 ; 利用逻辑分析实现倍频 ,使计数器的计数频率达到 16 0 MHz;
- A software of analyzing and processing ultrasonic detection signal with wavelet is developed with MATLAB6.1. MATLAB6.1 is a very useful and available tool for wavelet analysis and processing of ultrasonic signal. 利用MATLAB6.;1强大的各种工具箱、快速的编程风格和友好的图形界面等特点，编写了超声检测信号小波分析与处理软件，对超声检测信号进行了处理。 它在超声检测信号小波分析与处理方面是一个非常有用的工具。
- The wireless location electronic whiteboard based on ultrasonic signal has many advantages, but this type electronic whiteboard is easily interfered by aculeated sound signal because the frequency of the ultrasonic signal the frequency is lower. 我们实验室在基于无线定位理论的基础上，已成功研制成基于超声波信号定位的多功能交互式无线定位电子白板。 基于超声信号定位的无线定位的电子白板虽然有诸多优点，但是由于超声信号的频率较低，在实际应用场合极易受到其它尖锐声音信号的干扰。
- The doctors gave him an ultrasonic brain scan. 医生给他做了脑部超声波扫描检查。
- A red light is usually a signal of danger. 红灯通常是危险的信号。
- Signals control each section of the railway track. 各种信号控制着铁路轨道的每个部分。
- Much as bats do, instruments send out ultrasonic signals 机器就象蝙蝠那样地发出超声波讯号。
- I stood watching for the signal to change to green. 我站着等待交通信号转为绿灯。
- Let's set the clock by the radio time signal. 咱们照着收音机的报时信号把钟对一对。
- A period signals the end of a sentence. 句号表示一个句子结束了。
- A red lamp is often a danger signal. 红灯常常是危险的信号。
- A reflected signal on a communication channel. 一种在通信信道上反射回来的信号。
