Abstract Three typical elastic problems, including beam bending, truss extension and compression, two-rings collision are simulated with smoothed particle hydrodynamics (SPH) using Lagrangian Eulerian algorithms. A contact-force model for collisions equation of state pressure arising in colliding bodies also analytically derived. Numerical validations, on the corresponding theoretical models, c...

Interception of extrasolar objects is one the major current astrophysical objectives since it allows gathering information on formation and composition other planetary systems. This paper develops a tool to design optimal orbits for interception these bodies considering effects different perturbation sources. The trajectory obtained by solving Lambert’s problem that gives required initial impul...

Many animations depict two or more objects interacting and potentially colliding. Collision response is a complex process if the objects are intended to respond like soft bodies and to exhibit the properties of real objects. Physically-based models calculate contact forces to incorporate into the calculation of velocities and positions of the control mesh. Some physically-based models, for exam...

Context. Following the recent insight in the material structure of comets, protoplanetesimals are assumed to have low densities and to be highly porous agglomerates. It is still unclear if planetesimals can be formed from these objects by collisional growth. Aims. Therefore, it is important to study numerically the collisional outcome from low velocity impacts of equal sized porous agglomerates...

A computationally efficient technique to simulate the dynamic response of a beam colliding with rigid obstacles is described in this paper. The proposed method merges three key concepts. First, a low-order discretization scheme that maximizes the number of nodes of the discrete model (where impacts are detected) at the expense of the degree of continuity of the constructed displacement field is...

Context. Following the recent insight in the material structure of comets, protoplanetesimals are assumed to have low densities and to be highly porous agglomerates. It is still unclear if planetesimals can be formed from these objects by collisional growth. Aims. Therefore, it is important to study numerically the collisional outcome from low velocity impacts of equal sized porous agglomerates...

Dust distribution in disks supplied by small bodies: Is the β Pictoris disk a gigantic multi-cometary tail? Abstract. We have evaluated the spatial distribution of dust in disks supplied by colliding or evaporating bodies spread in a small belt. The gradient of the distribution of dust expelled by radiation pressure is generally steeper than the one observed around β Pictoris. It follows that, ...

The property that the stream cipher RC4 can generate the same keystream outputs under two different secret keys has been discovered recently. The principle that how the two different keys can achieve a collision is well known by investigating the key scheduling algorithm of RC4. However, how to find those colliding key pairs is a different story, which has been largely remained unexploited. Pre...