reference noise

Acoustics& Reference zero for the calibration of audiometric equipment Part 4: Reference levels for narrow-band masking noise

GB/T4854.4-1999声学校准测听设备的基准零级第4部分：窄带掩蔽噪声的基准级

The result provides valuable reference for projects including noise control diagnosis acoustical environment design etc.

计算结果可为噪声控制、故障诊断、声环境设计等工程实际应用提供有价值的参考.

Let the output of signal sensor be the original input and those of noise sensors as reference inputs, then noise caused by the change of orientation of magnetic field sensor relative to geomagnetism orientation can be eliminated efficiently, as well as bow wave due to carrier movement.

以信号传感器输出作为原始输入，噪声传感器输出作为参考输入，采用自适应噪声抵消技术，能有效消除因载体运动产生的涡流磁场及因磁探头方向相对地磁方向改变而引起的噪声输出。

Depth analysis of the threshold noise reduction algorithm of the threshold value functions and threshold threshold signal denoising, reference-based spectral subtraction speech enhancement algorithms based noise extraction of the door threshold to determine the algorithm.

深入分析了阈值降噪算法中阈值函数和门限阈值对信号去噪效果的影响，参考基于谱减法的语音增强算法，研究了一种基于噪声提取的门限阈值确定算法。

It constructs noise autocorrelation function with the use of noise autocorrelation in the high-frequency GPS coordinate time series, puts forward the Kalman filtering denoising model based on the fractal algorithm, and fulfills GPS subsidence deformation extract and the reference point coordinates settlement corrections. 3.

利用高频GPS坐标时间序列中噪声的自相关性构建了噪声自相关函数，提出基于分形算法的Kalman滤波消噪模型，实现GPS沉降变形的提取与基准点坐标的沉降改正。

Through analyzing and computing satisfy environmental noise criteria, a sort of noise absorption wall and sound insulation wall are introduced, which obtained good effect. It has reference value for outdoor machine design in air conditioning system.

在分析和计算了要满足环境允许噪声标准后，给出了一种吸音墙体和隔声挡墙的设计实例，达到了良好的治理效果，对空调系统室外机设计有参考价值。