In this paper we study the ultrasensitive behavior of multisite phosphorylation or ligand binding systems, under site-to-site variations in the modification rates. Using computational methods and mathematical analysis, we prove that the Hill coefficient reaches its maximum value when all sites are identical to each other. This is shown for a non-cooperative multisite system with arbitrary activ...

this paper presents approximate analytical solutions for nonlinear oscillators using the multi-step homotopy analysis method (msham). the proposed scheme is only a simple modification of the homotopy analysis method, in which it is treated as an algorithm in a sequence of small intervals (i.e. time step) for finding accurate approximate solutions to the corresponding problems. several illustrat...

Abstract This study presents the impact of near-field and far-field earthquakes on seismic design Intermediate Moment Resisting Frame (IMRF) Special (SMRF) structures through FEMA (Federal Emergency Management Agency) P695 methodology to highlight importance probabilistic collapse as well performance factors these structures. The purpose this is investigate steel intermediate special moment res...

In this paper, an experiment study with aspect ratio 100 of a circular cylinder was conducted in wave-current channel. The FBG sensors were attached on the which are used to capture vibration signal, two high-precision bellows type monitor fluctuant support force, and dynamic response finally calculated by modal analysis method. effect flow velocity, mass top tension amplitude ratio, frequency ...

The nonlinear dynamic response of atomic force microscopy cantilevers tapping on a sample is discussed through theoretical, computational, and experimental analysis. Experimental measurements are presented for the frequency response of a specific microcantilever-sample system to demonstrate the nonlinear features, including multiple jump phenomena leading to reproducible hysteresis. We show tha...

Hexagrid structural system is an innovated system with structural behavior which is similar to a tubular system. In this paper, a numerical study is conducted to estimate the seismic performance of horizontal hexagrid concerning the combined horizontal and vertical hexagrid, tubular and diagrid structural systems. First 30 and 50 story buildings are modeled using ETABS, then pushover and nonlin...

many of nonlinear systems in the field of engineering such as nano-resonator and atomic force microscope can be modeled based on duffing equation. analytical frequency response of this system helps us analyze different interesting nonlinear behaviors appearing in its response due to its rich dynamics. in this paper, the general form of duffing equation with cubic nonlinearity as well as paramet...

In Iran and some other countries, elastomer bearings in seat-type bridges are used with no sole/masonry plates and there is no positive connection between superstructure and substructure. Different codes have diverse provisions regarding the coefficient of friction (μ) between elastomer bearing and superstructure/substructure and also the design strength of shear keys (Vsk). Developing a finite...