Papers by Author: Hu Chen

Abstract: Under the condition that the increasing number of devices and invariable server hardware facilities in intelligent substation control system, an optimization algorithm of equipment polling strategy in intelligent substation control system is proposed in this paper. This paper proposes an equipment polling mechanism based on time slice scheduling, which is used to solve the problem that the entire network equipment need to detect at the same time on the hour, making the tremendous pressure to the control system. By using the proposed algorithm, it can effectively balance the load in the control system.

Abstract: In this paper, the effects of Na+ concentration on the overstretching transition of B-DNA molecule at physiological temperature are studied by both experimental and numerical methods. Using optical tweezers, the relationship of external force and relative extension is obtained by stretching single B-DNA molecule at 37°C. As the concentration increases from 0.909mM to 909mM, the overstretching transition force increases from 65.65 ± 1.2pN to 43.07 ± 1.2pN. An analytical expression is derived, which shows that overstretching transition force is linear with the natural logarithm of salt concentration. Based on a previous model, a three-dimensional model is proposed herein and solved by Metropolis Monte Carlo method. The bending deformation of DNA backbones, cooperativity of base-stacking interactions, electrostatic interactions, and spatial effects of DNA double helix structure are taken into account. Our key contribution is that the electrostatic energy is explicitly given as a function of folding angle and Na+ concentration. A new parameter is also introduced to account for the cooperativity of base-stacking interactions. The numerical results of this model are in good agreement with our experimental results.