Micromechanics models for the stiffness of aligned short-fiber composites are reviewed and evaluated. These include the dilute model based on Eshelby’s equivalent inclusion, the self-consistent model for finite-length fibers, Mori-Tanaka type models, bounding models, the Halpin-Tsai equation and its extensions, and shear lag models. Several models are found to be equivalent to the Mori-Tanaka a...

In this work, we use the rule of mixtures to develop an equivalent material model in which the total strain energy density is split into the isotropic part related to the matrix component and the anisotropic energy contribution related to the fiber effects. For the isotropic energy part, we select the amended non-Gaussian strain energy density model, while the energy fiber effects are added by ...

A carbon/glass hybrid fiber continuous sucker rod (CR) with lower specific gravity, better corrosion resistance and higher strength was developed to replace the steel in application of underground oil extraction. To meet actual needs fields, computer-aided design techniques based on mathematical optimization model are used help engineers optimizing CR pumping system. Because performance system,...

We study the existence and properties of birationally equivalent models for elliptically fibered varieties. In particular these have either structure Mori fiber spaces or, assuming some standard conjectures, minimal with a Zariski decomposition compatible elliptic fibration. prove relations between birational invariants variety, base fibration its Jacobian.

in this survey, asbestos fiber levels within the breathing zone of employers and in the environment of an asbestos-cement factory were monitored on membrane filter and counted by phase contrast optical microscope considering length/diameter>3:i (asbestos international associational method). the plant was fairly old and utilized both white (chrysotile) and blue (chrocidolite) asbestos. in each w...

during the last decades a new class of materials named fiber/metal laminates (fmls) was introduced. it is a hybrid composite consisting of alternating thin layers of metal sheets and fiber-reinforced composite material. fmls have both low weight and good mechanical properties. in this study, the impact behavior of this attractive material is investigated. the effect of fiber angle, stacking seq...

OBJECTIVE To examine if reductions in added sugar intake or increases in fiber intake in response to a 16-week intervention were related to improvements in metabolic outcomes related to type 2 diabetes mellitus risk. DESIGN Secondary analysis of a randomized control trial. SETTING Intervention classes at a lifestyle laboratory and metabolic measures at the General Clinical Research Center. ...

In many countries worldwide access networks are in the transition from copper to fiber access. During the transition phase copper and fiber networks are operated in parallel. All regulators facing this situation of technological change have to decide how to price unbundled access to the copper loop in this transition phase. Should they keep the usual forward looking long-run incremental cost st...