In this paper, we study theoretically and experimentally the friction between a rough parabolic or conical profile and a flat elastomer beyond the validity region of Amontons' law. The roughness is assumed to be randomly self-affine with a Hurst exponent H in the range from 0 to 1. We first consider a simple Kelvin body and then generalize the results to media with arbitrary linear rheology. Th...

In this paper, we investigated the temperature-dependent viscoelastic behavior of dielectric elastomers (DEs) and the effects of viscoelasticity on the electro-actuation behavior. We performed dynamic thermomechanical analysis to measure the master curve of the stress relaxation function and the temperature dependence of the relaxation time of VHB 4905, a commonly used DE. The master curve was ...

—Aimed at the path coverage problem for wireless multimedia sensor networks, MTPCA (Moving Target based Path Coverage-enhancing Algorithm) algorithm is proposed. This algorithm introduces the improved probabilistic model into the virtual potential field based directional sensor network coverage. In order to correct the centroid position of sector area covered by sensor node in traditional prob...

Gaining fundamental knowledge about diffusion in crowded environments is of great relevance in a variety of research fields, including reaction engineering, biology, pharmacy and colloid science. In this work, we determine the effective viscosity experienced by a spherical tracer particle immersed in a concentrated colloidal dispersion by means of Brownian dynamics simulations. We characterize ...

We describe a method for quantifying the mechanical properties of cells in suspension with a microfluidic device consisting of a parallel array of micron-sized constrictions. Using a high-speed charge-coupled device camera, we measure the flow speed, cell deformation, and entry time into the constrictions of several hundred cells per minute during their passage through the device. From the flow...

Gene expression is intrinsically a stochastic (noisy) process with important implications for cellular functions. Deciphering the underlying mechanisms of gene expression noise remains one of the key challenges of regulatory biology. Theoretical models of transcription often incorporate the kinetics of how transcription factors (TFs) interact with a single promoter to impact gene expression noi...

Xerogels and porous materials for specific applications such as catalyst supports, CO2 capture, pollutant adsorption and selective membrane design require fine control of pore structure, which in turn requires improved understanding of the chemistry and physics of growth, aggregation and gelation processes governing nanostructure formation in these materials. We used time-resolved dynamic light...

To get rid of the heavy burden of aspect ratio tuning, bias adjustment and porting problem among processes in full-custom or mixed-mode design, a fully digital smart temperature sensor realizable with 140 field programmable gate array (FPGA) logic elements was proposed for painless VLSI on-chip integrations. By simply replacing the cyclic delay line with a retriggerable ring oscillator for accu...

Studies of DNA molecule behavior in aqueous solutions performed through different approaches allow assessment of the solute-solvent interactions and examination of the strong influence of conformation on its physicochemical properties, in the presence of different ionic species and ionic concentrations. Firstly, the conformational behavior of calf-thymus DNA molecules in TE buffer solution is p...

In this article we study a simple, purely topological, cellular model which is allowed to evolve through a Glauber process. We find a non-thermodynamic transition to a glassy phase in which the energy (defined as the square of the local cell topological charge) fails to reach the equilibrium value below a critical temperature Tc, and depends strongly on cooling rate. We investigate a correlatio...