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101.
县级应急广播智能监控系统的设计应用 总被引:1,自引:0,他引:1
应急广播智能监控系统将视频与语音播控结合,在很多领域得到运用,对广播智能监控技术的特点进行介绍,分析智能监控技术在城市智慧广播视频中的具体应用。 相似文献
102.
特定声识别与定位系统 总被引:1,自引:0,他引:1
设计并实现了一种特定声识别与定位系统,应用于捕捉特定声源并判断其方位。系统将声音识别和定位两大功能有机结合,利用基于频域特性的相似度计算识别方法监测目标音频信号,定位方面,提出了对传统的基于到达时间差(TDOA)算法的系统优化。通过硬件电路预处理和软件设计相结合的方法,简便地计算出音频信号的到达时间差。再经过多重计算求... 相似文献
103.
104.
建立了音圈电机驱动的激光扫描器的模型并进行了参数辨识。由于音圈电机驱动的激光扫描器反馈回路的高频噪声较大,利用光电精密跟踪的传统方法,如改进型PID控制算法,以及理想闭环特性(最佳二阶特性)的逆向设计方法,系统并不能稳定工作,易振荡。分析了造成振荡的原因,采用前馈复合控制方法,避开了振荡因子同时又减小了稳态误差,解决了稳态误差和振荡的矛盾。结合反馈回路噪声大的特点,将滤波器加入反馈回路中,使激光扫描器不仅能稳定工作,消除了扫描时候的抖动,同时减少了线性扫描时候的磁滞现象。 相似文献
105.
106.
介绍了Digital Voice System. Inc公司的AMBE-1000芯片与挪威Nordic 公司的nRF401芯片的特点与工作原理,给出了一种基于AMBE-1000和nRF401的无线语音传输系统的实现.系统采用AMBE-1000 结合TCM320AC36C进行语音信号的处理;同时,采用nRF401传输数字化后的语音信号;在整体上,采用AT89C52 处理器负责接口之间的数据处理.提出了系统的硬件设计、软件流程.此系统具有无需许可证、功耗低、使用方便等特点,可广泛应用于无线语音传输系统的产品设计中. 相似文献
107.
Koichi Omori Ashutosh Kacker Linda M. Carroll William D. Riley Stanley M. Blaugrund 《Journal of voice》1996,10(3):228-235
This paper presents a parameter for objectively evaluating singing voice quality. Power spectrum of vowel sound / a / was analyzed by Fast Fourier Transform. The greatest harmonics peak between 2 and 4 kHz and the greatest harmonics peak between 0 and 2 kHz were identified. Power ratio of these peaks, termed singing power ratio (SPR), was calculated in 37 singers and 20 nonsingers. SPR of sung / a / in singers was significantly greater than in nonsingers. In singers, SPR of sung / a / was significantly greater than that of spoken / a /. By digital signal processing, power spectrum of sung / a / was varied, and the processed sounds were perceptually analyzed. SPR had a significant relationship with perceptual scores of “ringing” quality. SPR provides an important quantitative measurement for evaluating singing voice quality for all voice types, including soprano. 相似文献
108.
Harvey M. Tucker 《Journal of voice》1997,11(4):474-478
Including those patients that were the subject of our previous report in 1990 (1) a total of 52 patients with unilateral vocal fold paralysis have been managed by combined surgical medialization and nerve-muscle pedicle reinnervation. The technique has been modified only slightly since 1985, when the first such surgery was performed. Short- and long-term voice results determined by a panel of sophisticated listeners are reported, as well as details of patient selection and complications. Better functional results were noted than were observed with surgical medialization alone, and long-term deterioration of the voice improvement initially achieved was prevented with this technique. 相似文献
109.
110.
Peter Kitzing 《Journal of voice》1990,4(3)
Electroglottography (EGG) is a method to monitor the vibrations of the vocal folds by measuring the varying impedance to a weak alternating current through the tissues of the neck. The paper is an attempt to give a state-of-the-art report of how electroglottography is used in the clinic. It is based on a search of the pertinent literature was well as on an inquiry to 17 well known specialists in the field. The EGG techniques are described and limitations to the method are pointed out. Attempts to document voice quality by EGG are recognized and computerized methods to obtain information about vibratory perturbations and/or the vibratory frequency of the vocal folds are described. The author's personal conclusion is that the EGG signal is especially well suited for measurements of the glottal vibratory period. In the clinic such measurements are useful for periodicity analysis, as a basis for recording intonation contours, and to establish the characteristics of the voice fundamental frequency. 相似文献