We study the behavior of a naturally straight highly extensible elastic filament subjected to large extensional and twisting strains. We find that two different phases can coexist for a range of parameter values: the plectoneme and the solenoid. A simple theory based on a neo-Hookean model for the material of the filament and accounting for the slender geometry suffices to explain these observa...

A pair of objects on an inclined plane are connected together by a string. The upper object is then connected to a fixed post via a spring. The situation is first analysed as a classroom exercise in using free-body diagrams to solve Newton’s second law for a system of objects upon which many different kinds of force are acting (string tension, spring force, gravity, normal force, and friction)....

A sphere moving down the surface of a static sphere and a simple phase diagram. Abstract A small sphere placed on the top of a big static fric-tionless sphere, slips until it leaves the surface at an angle θ l = cos −1 2/3. On the other extreme, if the surface of the big sphere has coefficient of static friction , µ s → ∞, the small sphere starts rolling and continues to do so until it leaves t...

Direct numerical simulations of stably stratified homogeneous turbulence, with and without mean shear, are used to investigate the three-dimensional structure, evolution and energetic significance of density overturns. Although the flow conditions are idealized, examination of the full-field simulation data provides insight into flow energetics and mixing which may assist in the interpretation ...

The dynamics of the nonlinear Helmholtz Oscillator with fractional order damping is studied in detail. The discretization of the differential equations according to the Grünwald-Letnikov fractional derivative definition in order to get numerical simulations is reported. Comparison between solutions obtained through a fourth-order Runge-Kutta method and the fractional damping system is commented...

A sphere moving down the surface of a static sphere and a simple phase diagram. Abstract A small sphere placed on the top of a big static fric-tionless sphere, slips until it leaves the surface at an angle θ l = cos −1 2/3. On the other extreme, if the surface of the big sphere has coefficient of static friction , µ s → ∞, the small sphere starts rolling and continues to do so until it leaves t...

Shape memory alloys (SMAs) and in particular Ni-Ti alloys are commonly used in bioengineering applications as they join important qualities as resistance to corrosion, biocompatibility, fatigue resistance, MR compatibility, kink resistance with two unique thermo-mechanical behaviors: the shape memory effect and the pseudoelastic effect. They allow Ni-Ti devices to undergo large mechanically ind...

This paper designed a kind of automatic conveying and stamping machine, which was mainly used for drawing thin sheet metal. UGNX software to design the motion law mechanism simulation mechanism. The time displacement diagram obtained by theoretical calculation compared verify correctness analysis rationality design. comparison shows that device meets requirements calculation. has characteristic...

We report on transport properties in dual-gated hexagonal boron nitride (hBN)/bilayer-graphene (BLG) superlattices. Here, BLG is nontwisted, i.e., plain. This paper focuses the charge neutrality point (CNP) for a plain BLG. Under perpendicular magnetic field, transitions between two insulating phases at CNP are detected by varying displacement field with study resistance-temperature characteris...

lateral and anterior displacements of mandible may cause malocclusion. the aim of this study was to determine the prevalence of these displacements in a population of 597 childrens age 12 in mashhad secondary schools. displacment of mandible was shown to be in 11.8 percent of the population (6.2 percent anterior and 5.6 percent lateral displacement).anterior displacement of mandible was diagnos...