| 1. | The key of this method is that get the time when current value equal zero beforehand , and try to make the circuit break at that time
达到这个目的的思路是求取短路电流的过零点，试图在过零点切断电路。 |
| 2. | Judgment of the point of zero passage is the key factor involved , and a higher sampling frequency should be adopted when the method is applied on situations of large signal amplitude
其中过零点判定为关键技术，当用于信号幅值较大场合时应尽量提高信号采样频率。 |
| 3. | This paper uses " virtual neutral point method " to measure the " zero crossing " , then the soft deal " zero crossing " to get the six key position to commutate
本文采用虚拟中点的方法来识别反电势过零点，然后对过零点进行处理得到无刷电机换向的六个关键位置。 |
| 4. | Mostly , traditional arithmetic of image edge detection distill edge using gradient maximum or zero - crossing which base on gray discontinuousness on edge . they are affected easily by noise
传统的边缘检测算子大都是基于边缘的灰度不连续性利用梯度局部最大值或二阶导数过零点来检测边缘，容易受噪声干扰。 |
| 5. | The program is written by assemble language to control the movement of the vacuum circuit breaker with pma . the program also can monitor the environmental temperature , control voltage , closing displacement , zero point of contactor voltage
用汇编语言编制程序对配永磁机构的真空断路器的分、合闸进行控制，同时对其运行的环境温度、控制电压、合闸位移和触头间隙电压过零点等状态进行实时监测。 |
| 6. | Then one of the methods of rotor position detection - bemf zero crossing point detection is explained in detail . in succession , the chapter dissertates the method of measuring phase voltage and supply voltage , and analyses the error of rotor position using this method
对转子位置检测方法中的反电势过零点法作了比较详细的介绍，讨论了反电势法中相电压和端电压的检测方法，并分析了利用该方法时而产生的转子位置检测误差。 |
| 7. | The system uses the microchip pic16f877 made by microchip co . ltd as a control chip . it fulfills the capture of " zero crossing " point and the multifarious protective functions . it realize the approximately exact commutation of the motor and unmanned supervision of the system
本系统是以microchip公司生产的pic16f877为核心芯片，软硬件结合完成对反电势过零点的捕捉和系统的各种保护，实现了电机较为准确的换向和无人监控安全运行。 |
| 8. | Then the exisiting algorithms on iris location are studied and the disadvantages are pointed . a new approach based on edge detection , mathematic morphology and probability statistic is put forward . after studing the means of daugman ’ s encode of iris texture and w . w . boles ’ extraction the unique features by the zero - crossings of the wavelet transform , we adopted wavelet multi - resolution analysis that extract the feature
在研究和分析了前人的虹膜定位算法以及daugman对虹膜纹理的编码方法、 w . w . boles的小波过零点分析提取虹膜特征识别算法的基础上,研究了基于边缘检测和数学形态学以及概率统计等理论的一种新的虹膜定位方法;研究了虹膜图像的归一化和图像增强;研究了基于db4小波的多分辩率分析的虹膜特征提取算法;研究了相关系数匹配识别。 |
| 9. | Based on mono - pulse radar system and the analysis of terrain echoes , a geometrical model of air to ground ranging is constituted . by using the signals received from the sum and difference channels of terrain follow radar , a group of the expressions for terrain echoes are educed and characteristics of these echoes are obtained . according to the characteristics of the echoes , the theory and method of pass zero detection of difference channel and its applications are discussed in detail
针对一维单脉冲雷达体制，分析了地形目标回波特性；建立了地形跟随雷达空地测距的几何关系；利用雷达收发信号，导出了地形跟随雷达和差接收通道的回波信号表达式，进行了波形仿真，得到了地形跟随雷达的地面散射产生回波在时域中的特性；根据和差回波特性，阐述了差信号过零点检测测距的原理和方法及工程实践中的应用，并给出了真实雷达对外辐射试验的结果，验证了文中的仿真。 |
| 10. | A method of pitch mark determination for a speech , includes : acquiring a fundamental frequency point and fundamental frequency passband signals by using an adaptable filter ; detecting a number of passing zero positions of the fundamental frequency passband signals ; and generating at least a set of pitch marks from a number of passing zero positions
一种决定语音音高标记的方法，系藉以找出一语音之一组音高标记，此决定语音音高标记的方法系利用一可适性滤波器取得一基频点与一基频带通讯号；求取基频带通讯号之复数个过零点位置；然后经由复数个过零点位置产生至少一组音高标记。 |
