Lattice Boltzmann Simulation for Complex Flow in a Solar Wall

In this letter,we present a lattice Boltzmann simulation for complex flow in a solar wall system which includes porous media flow and heat transfer,specifically for solar energy utilization through an unglazed transpired solar air collector(UTC).Besides the lattice Boltzmann equation(LBE) for time evolution of particle distribution function for fluid field,we introduce an analogy,LBE for time evolution of distribution function for temperature.Both temperature fields of fluid(air) and solid(porous media) are modeled.We study the effects of fan velocity,solar radiation intensity,porosity,etc.on the thermal performance of the UTC.In general,our simulation results are in good agreement with what in literature.With the current system setting,both fan velocity and solar radiation intensity have significant effect on the thermal performance of the UTC.However,it is shown that the porosity has negligible effect on the heat collector indicating the current system setting might not be realistic.Further examinations of thermal performance in different UTC systems are ongoing.The results are expected to present in near future.     

代数次数为3的6元3维Bent函数的结构分析

Rothaus在其文章《On Bent Functions》中指出代数次数为3的6元Bent函数只有3个等价类．本文则推导出代数次数为3的6元Bent函数各等价类中函数的具体结构形式,并由此给出了以任意一个代数次数是3的6元Bent函数为分量的多维Bent函数的构造法．     

Random-phase-induced chaos in power systems

This paper studies how random phase (namely, noise-perturbed phase) effects the dynamical behaviours of a simple model of power system which operates in a stable regime far away from chaotic behaviour in the absence of noise. It finds that when the phase perturbation is weak, chaos is absent in power systems. With the increase of disturbed intensity $\sigma$, power systems become unstable and fall into chaos as $\sigma$ further increases. These phenomena imply that random phase can induce and enhance chaos in power systems. Furthermore, the possible mechanism behind the action of random phase is addressed.     

分布式发电系统感性负载的远程混沌同步

对含有大规模感性负载分布式发电系统（DG）的远程同步进行研究.以风力发电机作为DG发电节点,以永磁同步电机作为实际感性负载,建立一个具有网络耦合作用的DG数学模型,分析不同拓扑网络结构（包括星型、多层网络结构型、随机网络结构型、实际电网IEEE39系统）DG系统感性负载的远程同步特性,进行数值仿真.研究表明：感性负载通过发电机组的中继作用可实现远程混沌同步.研究结果对保证分布式发电系统的同步稳定运行具有意义.     

温度对吡啶离子液体性质影响的分子动力学模拟研究

运用分子动力学模拟方法研究了温度对三种吡啶离子液体[BPy][BF4]、[HPy][BF4]、[OPy][BF4]热力学性质的影响, 得到了每个体系的密度、自扩散系数、电导率和黏度等. 研究结果表明: 随着温度升高, 同一种离子液体的密度减小, 阴阳离子的自扩散系数明显增大, 电导率升高, 而黏度降低. 在同一温度下, 随着阳离子上烷基链的增长, 离子液体的密度减小, 但热力学性质的变化规律并不完全同步. 烷基链长最短的[BPy][BF4]的自扩散系数和电导率在每个温度下均为最大, 而黏度最小; 但烷基碳链更长的[OPy][BF4]和[HPy][BF4]的各种性质相差不大,甚至当温度大于323K时, 烷基链较长的[OPy][BF4]的自扩散系数比[HPy][BF4]的大.     

Passive adaptive control of chaos in synchronous reluctance motor

The performance of synchronous reluctance motor (SynRM) degrades due to chaos when its systemic parameters fall into a certain area. To control the undesirable chaos in SynRM, a passive control law is presented in this paper, which transforms the chaotic SynRM into an equivalent passive system. It is proved that the equivalent system can be asymptotically stabilized at the set equilibrium point, namely, chaos in SynRM can be controlled. Moreover, in order to eliminate the influence of undeterministic parameters, an adaptive law is introduced into the designed controller. Computer simulation results show that the proposed controller is very effective and robust against the uncertainties in systemic parameters. The present study may help to maintain the secure operation of industrial servo drive system.     

一类非线性弹性函数的构造

In this paper the decomposition formula of Walsh spectrum of boolean functions is used to construct a class of nonlinear resilient functions.     

电磁场耦合忆阻Izhikevich神经网络电活动研究

考虑到电磁场的影响,在Izhikevich神经元模型中引入电场变量和磁通变量,利用电突触耦合构建神经网络,研究电磁场耦合忆阻Izhikevich神经网络集体动力学行为。数值仿真发现：随着电突触耦合强度的增大,神经网络逐渐达到同步状态,并且神经元的放电模式也会随之改变。增大磁场耦合值可以提高神经元的放电活性,并且对网络同步也有一定的促进作用,而增大电场则会抑制神经元的放电活动。另外,当电突触与磁场耦合共同作用时,磁场耦合值越小,电突触耦合更能有效促进网络同步;在电突触耦合强度的作用下,电场抑制电活动的效果更明显。研究结果可望为理解神经系统中的信号编码和传递提供新的见解。