The accuracy of simulations of the plastic deformation of sheet metal depend to a large extend on the description of the yield surface, the hardening and the friction. In this paper simulations of deep drawing of an AlMg alloy with a shell model are presented. The yield surface is described by a Von Mises, a Hill ’48 and a Vegter yield function. The parameters for the model are based on biaxial...

The high cost of transportation fuels and the environmental risks associated with acquiring and using nonrenewable energy sources have created a demand for developing renewable bioenergy crops. Switchgrass ( L.), a warm-season perennial grass, is a promising feedstock due to its high biomass production under a wide range of growing conditions and its satisfactory forage quality and chemical com...

Secondary electron emission yield values for rare-gas particles (He, Ne, Ar, Kr, and Xe ions of atoms and molecules, metastable atoms, and excimers) of MgO deposited under optimum conditions for the highest values were calculated assuming the Auger transitions between the valence band, and the (oxygen ion vacancy + two electrons) and + (oxygen ion vacancy + one electron) centers in the MgO surf...

We report on a study of the light yield and surface treatment of barium fluoride (BaF2) scintillation crystals. Using a bialkali photocathode the photoelectron (p.e.) yield of BaF, crystals was measured to be 130 p.e./MeV for the fast components and 700 p.e./MeV for the slow component. A somewhat hygroscopic nature for the BaF, is found. Teflon film was found to be the best wrapping material fo...

This article presents a numerical technique for computing the biaxial yield surface of polymer-matrix composites with a given microstructure. Generalized Method of Cells in combination with an Improved Bodner-Partom Viscoplastic model is used to compute the inelastic deformation. The validation of presented model is proved by a fiber Bragg gratings (FBGs) strain test system through uniaxial tes...

For projector-based augmented reality systems, geometric correction is a crucial function. There have been many researches on the geometric correction in the literature. However, most of them focused only on static projection surfaces and could not give us a solution for dynamic surfaces (with varying geometry in time). In this paper, we aim at providing a simple and robust framework for projec...

This paper presents a physics-based approach to anatomical surface segmentation, reconstruction, and tracking in multidimensional medical images. The approach makes use of a dynamic \balloon" model|a spherical thin-plate under tension surface spline which deforms elastically to t the image data. The tting process is mediated by internal forces stemming from the elastic properties of the spline ...

Liquid wetting of a surface is omnipresent in nature and the advance of micro-fabrication and assembly techniques in recent years offers increasing ability to control this phenomenon. Here, we identify how surface roughness influences the initial dynamic spreading of a partially wetting droplet by studying the spreading on a solid substrate patterned with microstructures just a few micrometers ...

Submitted for the DFD05 Meeting of The American Physical Society Controlling the motion of vesicles along compliant substrates ROLF VERBERG, ALEXANDER ALEXEEV, ANNA BALAZS, University of Pittsburgh — To perform various biological assays and tissue engineering studies, it is vital to control the dynamic behavior of in vitro cells. In particular, there is a need for “smart” surfaces that can effe...