abstract: Innovative composite structures have been intensively studied towards meeting the demands of civil construction. An example such is slim floor, comprised concrete or slabs positioned at height steel beams, reducing total floor. In Brazil, studies on this system are still in early stages, and due to lack both experience national normative codes, it hardly used Given possible combinatio...

in this work a new resistance model has been presented based on that of henis-tripodi which can be used for interpretation of gas permeation data in composite and asymmetric membranes. in contrast to the previous works, in this model the fraction of the support layer surface that includes the pores filled with coating material has been taken into account. the influences of the filled pores on s...

trifluoromethylated organic compounds, especially chiral quaternary alcohols bearing trifluoromethyl group are of important intermediates in drugs, agrochemicals and etc.an efficient epoxidation of β-cf3-β,β-disubstituted unsaturated ketones (6) has been developed with environmental benign hydrogen peroxide as the oxidant and f5-substituted chiral quaternary ammonium salt (1g or 5) derived from...

background: existence or non-existence of adverse selection in insurance market is one of the important cases that have always been considered by insurers. adverse selection is one of the consequences of asymmetric information. theory of adverse selection states that high-risk individuals demand the insurance service more than low risk individuals do. methods: the presence of adverse selection ...

This paper presents a plausible reformulation and extension to the Bouc-Wen hysteresis model and gives an excellent summary and comparison of various theories of deteriorating constitutive models of hysteresis. A preliminary study on the effect of using overly simple hysteresis models (e.g., the bilinear model) when actual behavior includes strength degradation, stiffness degradation, and/or pi...

We present an active, purely mechanical stress wave isolator that consists of short cylindrical particles arranged in a helical architecture. This phononic structure allows us to change inter-particle stiffness dynamically by controlling the contact angles of the cylinders. We use torsional travelling waves to control the contact angles, thereby imposing a desired spatio-temporal stiffness vari...

Article history: In Caenorhabditis elegans, W Received for publication 28 July 2008 Revised 14 January 2009 Accepted 17 January 2009 Available online 29 January 2009

We wish to understand the role of electrostatics in DNA stiffness and bending. The DNA charge collapse model suggests that mutual electrostatic repulsions between neighboring phosphates significantly contribute to DNA stiffness. According to this model, placement of fixed charges near the negatively charged DNA surface should induce bending through asymmetric reduction or enhancement of these i...

BACKGROUND Polycystic ovary syndrome (PCOS) is associated with increased risk of cardiovascular disease (CVD). However, it is unknown whether CVD risk is equivalent across the different diagnostic categories or phenotypes of PCOS, particularly in the new phenotypes that affect up to 50% of women with PCOS. Surrogate markers of CVD include endothelial function and arterial stiffness that are ind...

This paper investigates the on-line estimation of parameters and the determination of the significance of several nonlinear and time varying linear effects in rotor dynamic systems. These effects include nonlinear spring restoring forces, nonlinear structural damping, and the asymmetric stiffness of the shaft. Since these effects are all linear in the parameter, a linear regression scheme can b...