BACKGROUND Open reduction and internal fixation with tension band wire is the standard treatment for displaced transverse patellar fractures. Recently, some minimally invasive techniques have been proposed as possible alternative methods. This retrospective study compared a newly reported percutaneous osteosynthesis with conventional open method for the treatment of displaced transverse patella...

the prevalent method of irrigation in paddy fields in iran is continuous ponding, which changes to intermittent method at the time of water shortage. soil cracks are the main problem in intermittent irrigation. in this study, effects of adding rice straw on some soil physical characteristics and cracks were studied in paddy soils of the guilan province of iran. the experiment was performed as s...

In this study, we investigated a method for the non-destructive detection of cracks based on an ultrasonic transit timing method. This method is considered to be an effective means for crack monitoring over an extensive coverage area. Aluminum specimens were prepared with a range of crack sizes and subjected to a tone burst wave to investigate the relationship between crack depth and the transi...

Remote laser welding (RLW) has shown a number of benefits joining 6xxx aluminium alloys such as high processing speed and process flexibility. However, the crack susceptibility during RLW is still an open problem. This paper experimentally assesses impact transverse micro cracks on joint strength fatigue durability in remote extruded AA6063-T6 fillet lap joints. Distribution morphology were acq...

An advanced, waveform based acoustic emission (AE) system was used to study the initiation of transverse matrix cracking in cross-ply graphite/epoxy (gr/ep) composites. The AE signals were detected with broad band, high fidelity sensors, and digitized for analysis. Plate wave propagation analysis was used to discriminate noise signals from those generated by cracks. The noise signals were confi...

We present an experimental study of the dynamics of rapid tensile fracture in brittle amorphous materials. We first compare the dynamic behavior of “standard” brittle materials (e.g. glass) with the corresponding features observed in “model” materials, polyacrylamide gels, in which the relevant sound speeds can be reduced by 2-3 orders of magnitude. The results of this comparison indicate unive...

Fracture modes in a model glass–polymer coating–substrate system indented with hard spheres are investigated. The large modulus mismatch between the glass and polymer results in distinctive transverse fracture modes within the brittle coating: exaggerated circumferential (C) ring cracks that initiate at the upper coating surface well outside the contact (as opposed to the near-contact Hertzian ...