However, the crack detection rate and reliability of these methods need further study.

但是，这些方法的裂纹检出率和可靠性需要深入研究。

Strain energy change is used as damage index and a nondestructive crack detection method is proposed.

把结构遭受裂缝损伤的应变能变化量作为损伤指标，提出一种新的无损裂缝识别方法。

The fracture flexibility of the bearing material should be enhanced and advanced crack detection technology should be adopted to monitor and control the main-shaft rolling bearing in practice.

在实际中 ，应尽量提高轴承材料的高断裂韧性并采用先进探伤技术以加强对主轴承的监控及监测。

The current domestic and abroad research status is discussed firstly, and the guided wave mode and exciting method used in pipeline crack detection is determined by disperse curve and wave structure.

首先，介绍了管道导波检测技术国内外的研究现状，然后利用频散曲线和波结构确定了管道裂纹检测所用的导波模态及激励方式。