In this paper we study analytically the viscous ‘sabra’ shell model of energy turbulent cascade. We prove the global regularity of solutions and show that the shell model has finitely many asymptotic degrees of freedom, specifically: a finite dimensional global attractor and globally invariant inertial manifolds. Moreover, we establish the existence of exponentially decaying energy dissipation ...

Terminal vascular beds continually adapt to changing demands. A theoretical model is used to simulate structural diameter changes in response to hemodynamic and metabolic stimuli in microvascular networks. Increased wall shear stress and decreased intravascular pressure are assumed to stimulate diameter increase. Intravascular partial pressure of oxygen (PO(2)) is estimated for each segment. De...

Microscopic robots could perform tasks with high spatial precision, such as acting on preciselytargeted cells in biological tissues. Some tasks may benefit from robots that change shape, such as elongating to improve chemical gradient sensing or contracting to squeeze through narrow channels. This paper evaluates the energy dissipation for shape-changing (i.e., metamorphic) robots whose size is...

Context. Visco-resistive damping in line-tied magnetic X-points is examined. Aims. The goal is to determine whether fast, Alfvénic energy dissipation is possible for X-point disturbances damped by the plasma resistivity and non-isotropic viscosity. Methods. The response of X-points to planar and axial perturbations is explored numerically by solving the linearized compressible MHD equations in ...

We present three-dimensional simulations of viscous dissipation of AGN induced gas motions and waves in clusters of galaxies. These simulations are motivated by recent detections of ripples in the Perseus and Virgo clusters. Although the sound waves generated by buoyant bubbles decay with distance from the cluster center, we show that these waves can contribute substantially to offsetting the r...

Shake table testing of a 1/5 scale model of a slender bridge steel truss pier that uses a controlled rocking approach as a means of seismic protection was conducted. The controlled rocking approach allows the pier to uplift from its base while passive energy dissipation devices steel yielding devices or fluid viscous dampers are implemented across the uplifting location to control the response....

The system of equations describing a nonstationary ow of a quasi-newtonian uid, with temperature dependent viscosity and with the viscous heating, is considered. Existence of at least one weak solution is proved, i.e. we get existence of at least one velocity eld having nite energy and existence of a nonnegative temperature eld. Its regularity is a consequence of the L 1-forcing term generated ...

Recently, we have reported use of Optical Coherence Tomography (OCT) and vibrational analysis to determine the resonant frequency of a material from which the moduli of decellularized dermis, pig skin, silicone rubber and chemically modified dermis were calculated. In this paper, we present data on viscoelastic mechanical properties of extracellular matrices and silicone rubber at frequencies a...

The paper numerically presents laminar forced convection of a nanofluid flowing in a duct at microscale. Results were compared with both analytical and experimental data and observed good concordance with previous studies available in the literature. Influences of Brinkman and Reynolds number on thermal and hydrodynamic indexes have been investigated. For a given nanofluid, no change in efficie...

The non-linear fluid dynamics of a warped accretion disc was investigated in an earlier paper by developing a theory of fully non-linear bending waves in a thin, viscous disc. That analysis is here extended to take proper account of thermal and radiative effects by solving an energy equation that includes viscous dissipation and radiative transport. The problem is reduced to simple one-dimensio...