Ultrasonic signal classification in nondestructive testing is of great significance for the detection defects. The current methods have mainly utilized low-level handcrafted features based on traditional processing approaches, such as Fourier transform, wavelet transform and like, to interpret information carried by signals classification. This paper proposes an automatic method via a convoluti...

OBJECTIVE Estimates of ultrasonic attenuation (the loss of energy as an ultrasonic wave propagates through tissue) have been used to evaluate the structure and function of tissues in health and disease. The purpose of this research was to develop a method to estimate ultrasonic cervical attenuation during human pregnancy using a clinical ultrasound system. METHODS Forty women underwent a cerv...

In this study, the feasibility of using a one dimensional 16-element flexible ultrasonic transducer (FUT) array for nondestructive testing at 150 °C is demonstrated. The FUT arrays were made by a sol-gel sprayed piezoelectric film technology; a PZT composite film was sprayed on a titanium foil of 75 µm thickness. Since the FUT array is flexible, it was attached to a steel pipe with an outer di...

Ultrasonic pulse-echo C-scan imaging is a widespread method for detecting and characterizing defects in fiber reinforced polymer composites. However, the accurate assessment of complex distributed damage cluster, like barely visible impact damage, multi-layer heterogeneous composites not straightforward. For reliably estimating remaining load carrying capacity and/or useful lifetime damaged com...

In ultrasonic defectoscopy it is very difficult to detect flaws in materials with coarse-grain structure. Measured ultrasonic signal contains echoes from flaw and echoes from grains included in material. These echoes characterized noise have to be cancelled. A common source of noise is electronic circuitry, which is used for processing of the ultrasonic signal, and scattering at the inhomogenei...

Owing to the successful use of phased array probes in automatic testing machines, more and more applications can now be found in the field of manual inspections. Miniaturization of electronic components and improvements of processing speed allow the integration of phased array hardware into a small, battery driven instruments for fast ultrasonic imaging. The advantages of the phased array techn...

Ultrasonic pulse echo flaw detection systems have been widely used in the field of nondestructive testing for quite long time. Theoretical studies made in the 1970’s and early 1980’s suggest that ultrasonic NDT using pulse compression technique can overcome some of the drawbacks of classical pulse echography. The limitation of currently available ultrasonic instruments hardly lies on the proper...

Following the “on condition maintenance” approach used for extending service life of an aircraft one of the major tasks is a nondestructive testing of its critical elements. Considering that many of elements of operated aircraft are manufactured from polymeric composites a special attention should be paid for diagnosing these elements due to their high vulnerability to barely visible impact dam...