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Urban public transit system is a typical mixed complex network with dynamic flow, and its evolution should be a process coupling topological structure with flow dynamics, which has received little attention. This paper presents the R-space to make a comparative empirical analysis on Beijing’s flow-weighted transit route network (TRN) and we found that both the Beijing’s TRNs in the year of 2011 and 2015 exhibit the scale-free properties. As such, we propose an evolution model driven by flow to simulate the development of TRNs with consideration of the passengers’ dynamical behaviors triggered by topological change. The model simulates that the evolution of TRN is an iterative process. At each time step, a certain number of new routes are generated driven by travel demands, which leads to dynamical evolution of new routes’ flow and triggers perturbation in nearby routes that will further impact the next round of opening new routes. We present the theoretical analysis based on the mean-field theory, as well as the numerical simulation for this model. The results obtained agree well with our empirical analysis results, which indicate that our model can simulate the TRN evolution with scale-free properties for distributions of node’s strength and degree. The purpose of this paper is to illustrate the global evolutional mechanism of transit network that will be used to exploit planning and design strategies for real TRNs.

Forward blowing from a pair of plasma actuators on the leeward surface and near the apex is used to switch the asymmetric vortex pair over a cone of semi-apex angle 10° at high angles of attack. Wind tunnel pressure measurements show that by appropriate design of the actuators and appropriate choice of the AC voltage and frequency, side forces and yawing moments of opposite signs can be obtained at a given angle of attack by activating one of the plasma actuators. Further work is suggested.

Unlike earlier academic endeavors on a single fluid, liquid metals are found to be uniquely important when used along with other solutions which are especially critical in many applications. In this sense, the hydrodynamic properties of liquid metal and allied fluids made of liquid metal/aqueous solution are elementary in the design and operation of various functional devices or systems involved. In terms of the general physical and chemical properties, such as density, thermal conductivity, and electrical conductivity, the huge differences between the two fluidic phases of liquid metal and conventional fluid raise a big challenge for quantifying the hybrid flow behaviors [1]. Interesting enough, the liquid metal immersed in the solution would easily move and deform when administrated with external non-contact electromagnetic force, or even induced by redox reaction, which is entirely different from the cases of a single fluid or conventional contacting force. Owing to its remarkable capability for flow and deformation, liquid metal immersed in the solution is apt to deform on an extremely large scale, resulting in marked changes on its boundary and interface. However, until now, the working mechanisms of the movement and deformation of liquid metal in the allied solution environment still lack appropriate models to describe such scientific issues via a set of well-established unified theories. To promote deep understanding of liquid metal in future biomedical applications where hybrid or even multiple phase fluids are often involved, this chapter is dedicated to illustrate the unconventional hydrodynamics from experiment, theory, and simulation aspects. Typical phenomena and basic working mechanisms are explained. Some representative simulation methods are incorporated to tackle the governing functions of the electrohydrodynamics. Further, prospects and challenges are raised, which is to offer a startup insight into the new physics of hybrid fluids under applied fields.