The motion of particles in different channel Brownian pumps can be described by Langevin equations,and the pumping capacity is a useful indicator to demonstrate the strength of a pump’s transportation ability.Via the...The motion of particles in different channel Brownian pumps can be described by Langevin equations,and the pumping capacity is a useful indicator to demonstrate the strength of a pump’s transportation ability.Via the simulation,there is always an optimal value of temperature and unbiased external force for different pumps which make the concentration ratio between the right tube and left tube derive its maximum and minimum in two asymmetric tubes respectively.Besides,the concentration ratio will keep 1 regardless of radius,temperature or magnitude of force in the tube in a symmetric tube.To obtain more information about pumping capacity,exploring the average probability current(APC) of tubes in different conditions is necessary.Results indicate that as the concentration ratio is 1,the change of the APC when x_(0)=0 is similar to that when x_(0)=π.Also,when the concentration ratio is more than 1,there are optimal values of temperature,radius and magnitude of force where the APC gains a maximum,and the maximum decreases as the concentration in the right tube increases when x_(0)=0.展开更多
The Louvre is a famous French building and a tourist attraction.It is of great significance to make an emergency evacuation plan for tourists.A social force model and cellular automata were established to simulate the...The Louvre is a famous French building and a tourist attraction.It is of great significance to make an emergency evacuation plan for tourists.A social force model and cellular automata were established to simulate the crowd evacuation in unidimensional plane,and then the downstairs model was considered to simulate three-dimensional evacuation.Finally the real evacuation situation was simulated,considering the hazard source as well as other factors.The study found that the exit was closer to the corner,and the evacuation distance of descending stairs could be controlled between 0.3 and 0.6 m to maximize evacuation efficiency.The influence of the hazard at the edge of the channel was greater than that at the center of the channel.Therefore,in the process of evacuation,the staff should be guided to the nearest exit,to maintain the optimal distance,the staff to eliminate the danger source in the center of the passage.展开更多
基金National Natural Science Foundation of China (No. 61975058)Blue Shield Technology Project,China (No. LD20170209)。
文摘The motion of particles in different channel Brownian pumps can be described by Langevin equations,and the pumping capacity is a useful indicator to demonstrate the strength of a pump’s transportation ability.Via the simulation,there is always an optimal value of temperature and unbiased external force for different pumps which make the concentration ratio between the right tube and left tube derive its maximum and minimum in two asymmetric tubes respectively.Besides,the concentration ratio will keep 1 regardless of radius,temperature or magnitude of force in the tube in a symmetric tube.To obtain more information about pumping capacity,exploring the average probability current(APC) of tubes in different conditions is necessary.Results indicate that as the concentration ratio is 1,the change of the APC when x_(0)=0 is similar to that when x_(0)=π.Also,when the concentration ratio is more than 1,there are optimal values of temperature,radius and magnitude of force where the APC gains a maximum,and the maximum decreases as the concentration in the right tube increases when x_(0)=0.
基金National Natural Science Foundation of China(No.61975058)Blue Shield Technology Project,China(No.LD20170209)。
文摘The Louvre is a famous French building and a tourist attraction.It is of great significance to make an emergency evacuation plan for tourists.A social force model and cellular automata were established to simulate the crowd evacuation in unidimensional plane,and then the downstairs model was considered to simulate three-dimensional evacuation.Finally the real evacuation situation was simulated,considering the hazard source as well as other factors.The study found that the exit was closer to the corner,and the evacuation distance of descending stairs could be controlled between 0.3 and 0.6 m to maximize evacuation efficiency.The influence of the hazard at the edge of the channel was greater than that at the center of the channel.Therefore,in the process of evacuation,the staff should be guided to the nearest exit,to maintain the optimal distance,the staff to eliminate the danger source in the center of the passage.
