The article analyzed the deficiency of traditional method of triage.

The results show that the method of canceling noise is better,and this grounds for the bug detection and location of damage identification.

An analysis method of structural damage identification is presented based on.

Vibration_based damage identification is one of the few methods that detect changes in the structure on a global basis.

An improved crack detection method using modal frequencies of jacket platforms;

And the newest development in the area of crack detection is also summarized.

The lowest ten natural frequencies and modal shapes of the jacket models are calculated by finite element method,The evaluated modal parameters of the models with a crack at different location or of different depth in the underwater structure are calculated numerically for crack detection.

Application study of an improved genetic algorithm for frame structure damage detection;

Structural damage detection based on modulus maximized wavelet transform of vibration mode;

Application of BP artificial neural networks to structural damage detection and recognization;

Study on flaw detection of hoisting cable;

This essay gives us a brief introduction about the principle of the flaw detection with ultrasonic wave and the quality inspection of hard metal for cubic anvil,analyses the method of the Ultrasonic wave flaw detection.