– The problem of finding what direction cracks should move is not completely solved. A commonly accepted way to predict crack directions is by computing the density of elastic potential energy stored well away from the crack tip, and finding a direction of crack motion to maximize the consumption of this energy. I provide in this letter a specific case where this rule fails. The example is of a...

We present a molecular dynamics simulation study on the effects of crack formation mechanical properties bilayer graphene. Bilayer graphene possesses unique electronic that can be modified by applying voltage, making it an attractive material for various applications. examined how vary under configurations and temperatures, measuring Young’s modulus, fracture toughness, strain, stress. compared...

Beyond the limelight of teaching hospitals, the psychiatric profession is in a state of near-collapse. A lack of resources and man-power is resulting in an incomplete service which is unfair to patients and demoralising for doctors-the situation needs salvaging, and soon.

We have conducted experiments and numerical simulations to investigate supersonic cracks. The experiments are performed at 85 ◦C to suppress strain-induced crystallites that complicate experiments at lower temperature. Calibration experiments were performed to obtain the parameters needed to compare with a theory including viscous dissipation. We find that both experiments and numerical simulat...

Stress corrosion cracks (SCC) in low-pressure steam turbine discs are serious hidden dangers to production safety in the power plants, and knowing the orientation and depth of the initial cracks is essential for the evaluation of the crack growth rate, propagation direction and working life of the turbine disc. In this paper, a method based on phased array ultrasonic transducer and artificial n...

Abstract-An alternating method, in conjunction with the finite element method and a solution for multiple coplanar elliptical cracks in an intinite solid, is used to determine stress intensity factors for semi-elliptical surface flaws in cylindrical pressure vessels. The solution technique for multiple cracks in an infinite body has recently been developed by the prese.nt authors which implemen...

The Northern Long-eared Myotis (Myotis septentrionalis) is known to hibernate in mines and caves, often using cracks within these hibernacula as roost sites. We hypothesized that M. septentrionalis might use deep cracks in rock outcrops for hibernation as well. To test this hypothesis, we placed acoustical bat detectors near rock outcrops away from any known mines or caves during winter in Nebr...

Automated systems for road crack detection are extremely important in road maintenance for vehicle safety and traveler’s comfort. Emerging cracks in roads need to be detected and accordingly repaired as early as possible to avoid further damage thus reducing rehabilitation cost. In this paper, a robust method for Gabor filter parameters optimization for automatic road crack detection is discuss...

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...