The severe numerical instability in complex frequency modal mass identification from frequency response function makes it difficult to identify physical parameters.
利用频响函数识别复频率模态质量存在着严重的数值计算不稳定性，给物理参数的识别造成困难。
At the stage of Mass Production, technology knowing and identification on product competitive advantage are significant.
在规模生产阶段，技术知晓性和企业对产品竞争优势的正确识别影响显著。
In physics it is an identification of material by noting its mass per unit volume.
在物理学上，是以每单位体积的质量来鉴别物质。
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