in this paper, penetration of high velocity impact of 4340 steel and tungsten carbide projectiles with specific shapes in to ceramic armor that includes 10 mm alumina (95%) is considered analytically and simulated with ls-dyna software. bernoulli equation used to consider the penetration velocity in ceramics, shows that the penetration is better and easier by increasing projectile density. the ...

Three separate impact events were simulated (LS-DYNA ® ) based on experimental tests previously conducted [2] (i.e., the appropriate impact velocities assigned to the model projectile): i) a pre-fracture event (2.1 m/s); ii) a crack event (2.7 m/s); and iii) a fracture event (3.3 m/s). Two element sets were created in the locations of the experimental strain gauges (dorsal radial styloid and do...

This paper demonstrates the application of a numerical methodology for a full-scale aircraft impact crashworthiness investigation. We studied the impact of an aircraft wing with a tree using LS-DYNA and ANSYS CFX. In particular, a detailed finite element model of the wing structure was represented as a box structure containing skin, spars and ribs, and fuel was represented as a distributed mass...

We hypothesized that elevated base deficit (BD) ≥ 4 mEq/L upon admission could be associated with an altered inflammatory response, which in turn may impact differential clinical trajectories. Using clinical and biobank data from 472 blunt trauma survivors, 154 patients were identified after excluding patients who received prehospital IV fluids or had alcohol intoxication. From this subcohort, ...

0167-6636/$ see front matter 2009 Elsevier Ltd doi:10.1016/j.mechmat.2009.09.009 * Corresponding author. Address: University of Ca Mechanical and Aerospace Engineering, 4909 Eng 9500 Gilman Drive, La Jolla, CA 92093-0416, USA. T E-mail address: [email protected] (S. Nemat-Nasser). Results of computationalmodeling and simulation of the response ofmonolithicDH-36 steel plates and bilayer steel-polyure...

During sporulation, the filamentous bacteria Streptomyces undergo a massive cell division event in which the synthesis of ladders of sporulation septa convert multigenomic hyphae into chains of unigenomic spores. This process requires cytokinetic Z-rings formed by the bacterial tubulin homolog FtsZ, and the stabilization of the newly formed Z-rings is crucial for completion of septum synthesis....

Prediction of formability for sheet metal pressings has advanced to a high state of confidence in recent years. The major challenge is now to predict springback and, moreover, to assist in the design of tooling to correctly compensate for springback. This is particularly the case for materials now being routinely considered for automotive production, such as aluminium and ultra high strength st...

In this paper, we present two software packages, HexGen and Hex2Spline, that seamlessly integrate geometry design with isogeometric analysis (IGA) in LS-DYNA. Given a boundary representation of solid model, creates hexahedral mesh by utilizing semi-automatic polycube-based generation method. Hex2Spline takes the output from as input control constructs volumetric truncated hierarchical splines. ...

We study three-dimensional finite transient deformations of transparent poly-methyl-methacrylate (PMMA)/adhesive/polycarbonate (PC) laminates impacted at low speed by a hemispherical nosed rigid cylinder using the commercial finite element (FE) software LS-DYNA. The two glassy polymers PMMA and PC are modeled as thermo-elasto-visco-plastic materials by using the constitutive relation proposed b...

Model-free and model-based reinforcement learning have provided a successful framework for understanding both human behavior and neural data. These two systems are usually thought to compete for control of behavior. However, it has also been proposed that they can be integrated in a cooperative manner. For example, the Dyna algorithm uses model-based replay of past experience to train the model...