Ultrasonic techniques have the potential to provide early detection of fatigue induced cracks originating from fastener holes with the long term goal of structural health monitoring. This paper considers energy-based algorithms for analyzing ultrasonic waveforms obtained using fixed angle beam transducers in a through-transmission configuration. The transducers were located on either side of th...

In situ ultrasonic methods for structural health monitoring have the potential to provide early detection of fatigue cracks in aircraft components, specifically cracks initiating from fastener holes. A dual angle beam technique based upon an incident shear wave and a spiral creeping wave propagating around the hole has been shown to be a viable configuration for monitoring of fastener hole crac...

This paper presents a new self-clinching fastener to connect two sheets (or plates), made from similar or dissimilar materials, placed over one another by means of mechanical form-closed joint that is hidden inside the sheets. The development fastener, definition its main design variables and identification workability limits are carried out combined experimental numerical simulation work based...

As an important part of track inspection, the detection rail fasteners is great significance to improve safety train operation. Additionally, fastener belongs small-target detection. The YOLOv4 algorithm relatively fast in and has some advantages Therefore, used for status However, still suffers from following two problems First, features extracted by original feature extraction network are rou...

Slide fasteners are one of the textile end-uses that have permeated daily life. The objective is to elucidate ways improve quality and value slide fasteners. In this report, from viewpoint tactile perception on tensile load transmitted user’s fingers through a slider in sliding fastener, sensory affective impressions (hereinafter referred as slide-feeling) quantitative evaluation indexes slide-...

Traveling by high-speed rail and railway transportation have become an important part of people’s life social production. Track is the basic equipment transportation, its performance directly affects service lifetime lines vehicles. The anomaly detection fasteners in a priority, while traditional manual method extremely inefficient dangerous to workers. Therefore, this paper introduces efficien...

Thin solid shell contrast agents bubbles are expected to undergo different volume oscillating behaviors when the acoustic power is increased: small oscillations when the shell remains spherical, and large oscillations when the shell buckles. Contrary to bubbles covered with thin lipidic monolayers that buckle as soon as compressed: the solid shell bubbles resist compression, making the buckling...