Preventing broken-rail-caused derailments is a high priority for the rail industry and government. The current practice is to periodically inspect rails using non-destructive technologies such as ultrasonic rail inspection. Determining the optimal inspection frequency is a critical decision in railway infrastructure management. The objective of this paper is to develop an analytical framework t...

Rail surface defects such as the abrasion, scratch and peeling often cause damages to the train wheels and rail bearings. An efficient and accurate detection of rail defects is of vital importance for the safety of railway transportation. In the past few decades, automatic rail defect detection has been studied; however, most developed methods use optic-imaging techniques to collect the rail su...

The oscillatory behavior of CNT oscillators, initially subjected to bending, is studied under constant temperature using molecular dynamics simulations. We constrain the rotational motion of the inner CNT by imposing a small bending deformation to the initial structure. Our observation suggests that this constraint does not enhance the oscillation stability of CNT oscillators. However, oscillat...

Abstract An acoustic emission (AE) approach for non-destructive evaluation of structures has been developed over the last two decades. In complex structures, one limitations AE testing is to find location source. Time flight and wave velocity are typically employed localise sources. However, rail generate multiple modes travelling at varying speeds, making localisation difficult. this paper, ch...

the influence of flour content and immersion time in water on the creep behavior of composites made from high density polyethylene (hdpe) waste and mdf (medium density fiberboard) flour was investigated. mixing was carried out by a twin screw extruder and the sample was manufactured by flat hot press. firstly, the modulus of elasticity and bending strength of various mdf flour-polyethylene comp...

We investigate the bending of nanometer thick Si cantilevers induced by chemisorption of H atoms and acetylene molecules, using atomistic simulations and continuum theories. We show that the bending curvature of Si nanocantilevers does not follow the classical Stoney formula, but agrees well with a modified Stoney formula that we have derived. Our studies reveal the dominant role of atomic stru...

The three-point bending strength and fracture behavior of single oriented crossed-lamellar structure in Scapharca broughtonii shell were investigated. The samples for bending tests were prepared with two different orientations perpendicular and parallel to the radial ribs of the shell, which corresponds to the tiled and stacked directions of the first-order lamellae, respectively. The bending s...

We investigate various swimming modes of Paramecium in geometric confinements and a non-swimming self-bending behavior like a somersault, which is quite different from the previously reported behaviors. We observe that Paramecia execute directional sinusoidal trajectories in thick fluid films, whereas Paramecia meander around a localized region and execute frequent turns due to collisions with ...