Automated Classification of Pipeline Defects from Ultrasonic Phased Array Total Focusing Method Imaging

Abstract

The defects in the welds of energy pipelines have significantly influenced their safe operation. The inefficient and inaccurate detection of the defects may give rise to catastrophic accidents. Ultrasonic phased array inspection is an important means of ensuring pipeline safety. The total focusing method (TFM), using ultrasonic phased arrays, has become widely used in recent years in non-destructive evaluation (NDE). However, manual defect recognition of TFM images is seen to lack accuracy and robustness, arising from deficiency of practical experience. In this paper, the automated classification of different defects from TFM images is studied with a view to facilitate inspection efficacy. By experimentally implementing the TFM approach on a bespoke specimen, the images corresponding to crack-like defects and pore-like defects were employed to investigate the effectiveness of four different machine learning models (known as Support Vector Machine, CART Decision tree, K Nearest Neighbors, Naive Bayes) containing data augmentation, feature extraction and defect classification. The results suggested that the accuracy of defect classification using the HOG-Poly-SVM algorithm was 93%, which outperformed the results from other algorithms. The advantage of the HOG-Poly-SVM algorithm used in defect classification of ultrasonic phased array TFM data is discussed by conducting ten-fold cross validation and other evaluation metrics. In this paper, in order to improve the efficiency of detecting pipeline defects in the future, and for testing test blocks simulating buried pipelines containing defects, we proposed, for the first time, that ultrasonic phased-array TFM imaging results in small object detection images, and found that the SVM algorithm was applicable to ultrasonic phased array TFM imaging, providing a research method and ideas for the use of artificial intelligence in industrial non-destructive testing.

Current realities of home blood pressure monitoring from physicians’ perspectives: results from Asia HBPM survey 2020

“…In addition, physicians identified concerns with the accuracy and reliability of HBP devices as a key factor hindering the recognition of HBPM by physicians and patients. This could be attributed to the lack of instructions on device calibration in the local guidelines of most countries/regions, except for China, Indonesia, and Japan [15][16][17]. As with all devices, it is important to ensure HBP monitors are calibrated and Local guidelines should advocate using calibrated HBPM devices and provide specific instructions on calibration to support accurate measurements [18].…”

“…Our results showed that, while a high proportion of physicians recommended HBPM to their patients, discrepancies between HBPM recommendations in guidelines and practice realities were prevalent. For instance, all of the countries/regions surveyed, except for the Philippines, recommended 135/85 mmHg as the diagnostic threshold for hypertension by HBP in general population in their guidelines (Supplementary Table 4) [15][16][17][19][20][21][22][23][24][25][26]. However, overall, only one-fifth of the physicians cited 135/85 mmHg as the diagnostic threshold for HBPM.…”

“…Further analysis showed a similar low proportion (22.4%) among physicians who indicated they recommended HBPM to their patients. Although most of the countries/regions recommended measuring HBPM before taking antihypertensive 4) [15][16][17][19][20][21][22][23][24][25][26], only slightly more than half of the physicians provided instructions that were consistent with guidelines recommendations. These findings were corroborated by local HBPM surveys of physicians in Indonesia, Japan, and Singapore which revealed that at least 94% recommended HBPM to hypertensive patients, however, a substantial proportion of physicians gave instructions that were inconsistent with guidelines recommendations for HBPM [13,27,28] Taken together, these findings suggest that even when HBPM is conceptually recognized by physicians and recommended to patients, there is still suboptimal translation of guideline recommendations to actual clinical practice across the participating countries.…”

Fabrication of micro-ultrasonic phased array electrode via electric field-driven printing method

“…Micro-ultrasonic phased array is widely applied in medical testing [1,2] and industrial inspection [3,4], because of its nondestructive detection mode. The micro-ultrasonic phased array is mainly composed of a piezo element, an electrode, a matching layer, and a flexible circuit [5], where the role of the * Author to whom any correspondence should be addressed.…”