Liang-gang Liu

Learn More
We study the steady state properties of an insect (spruce budworm) outbreak model in the presence of Gaussian white noise. Based on the corresponding Fokker-Planck equation the steady state solution of the probability distribution function and its extrema have been investigated. It was found that fluctuations of the insect birth rate reduces the population(More)
Numerical simulations of pulsating blood flow through models of stenotic and tapered arteries have been performed to investigate the distributions of the wall shear stress. In this paper, a mathematical model of a rigid tapered artery with axially symmetric stenosis is established. The incompressible Navier-Stokes equations are solved numerically by using(More)
The logistic differential equation is used to analyze cancer cell population, in the presence of a correlated Gaussian white noise. We study the steady state properties of tumor cell growth and discuss the effects of the correlated noise. It is found that the degree of correlation of the noise can cause tumor cell extinction.
Transport of a Brownian particle moving along the axis of a three-dimensional asymmetric periodic tube is investigated in the presence of asymmetric unbiased forces. The reduction of the coordinates may involve not only the appearance of entropic barrier but also the effective diffusion coefficient. It is found that in the presence of entropic barrier, the(More)
In this paper, a previous coarse-grain model [J. T. Padding and W. J. Briels, J. Chem. Phys. 117, 925 (2002)] to simulate melts of linear polymers has been adapted to simulate polymers with more complex hierarchies. Bond crossings between highly coarse-grained soft particles are prevented by applying an entanglement algorithm. We first test our method on a(More)
This paper investigates a three-dimensional periodic tube driven by spatially modulated Gaussian white noise. We derive an analytical expression for the net current by introducing entropic barriers. It is found that the phase shift between the entirely symmetric tube and noise modulation can break the symmetry of the generalized potential and induce(More)
An analysis is presented of forces acting on the centers of mass of three-armed star polymers in the molten state. The arms consist of 35 Kremer-Grest beads, which is slightly larger than needed for one entanglement mass. For a given configuration of the centers of mass, instantaneous forces fluctuate wildly around averages which are two orders of magnitude(More)
The efficiency of a Brownian particle moving in a periodic potential in the presence of asymmetric unbiased fluctuations is investigated. We found that even on the quasistatic limit there is a regime where the efficiency can be a peaked function of temperature, which proves that thermal fluctuations facilitate the efficiency of energy transformation,(More)
In 1991, we proposed a model in which nucleus is=20 treated as a spherical symmetric MIT bag and nucleon satisfies the MIT bag model boundary condition. The model was employed to calculate=20 nuclear magnetic moments. The results are in good agreement with=20 experiment data. Now, we found this model is still interesting and=20 illuminating.(More)
A Brownian pump of particles in an asymmetric finite tube is investigated in the presence of an unbiased external force. The pumping system is bounded by two particle reservoirs. It is found that the particles can be pumped through the tube from a reservoir at low concentration to one at the same or higher concentration. There exists an optimized value of(More)