Narrow Results

Connected vehicles are expected to become commercially available by the next decade, while traffic interruption is not uncommon in the real traffic environment. In this paper, we propose a feedback control method for lattice hydrodynamic model considering the traffic interruption probability effect. The stability criterion of the new model is explored through linear stability analysis of transfer function. When the stability conditions are not satisfied, a delay feedback controller is used to control the discharging flow to suppress traffic congestion. The impact of gain coefficient and delay time on the performance is discussed. We verify the effectiveness of the devised delay feedback controller by simulations. Results show that the traffic interruption probability effect has a considerable impact on the stability of traffic flow, while the controller is effective in suppressing traffic congestion.

A new method of projective synchronization of unidentical chaotic systems is proposed in this letter. This method is based on the stability criterion of linear systems. The response of two unidentical chaotic systems can synchronize up to any desired scaling factor by a suitable separation of the systems. The new method of projective synchronization is suitable not only for the three-dimensional coupled partially linear systems, but also for higher dimensional even hyperchaotic systems. The simplicity and effectiveness of the proposed method are illustrated by the Lorenz system, the four-dimensional partially linear system, the four-dimensional hyperchaotic Rösser system and Chua's circuit system as four numerical examples.

We present a family of relativistic fluid spheres using the Karmarkar criterion along with the Pandey–Sharma condition. Ranges of $n$ and $m$ for well-behaved solutions depend on the mass and radius of the compact star model. As an example, we have chosen Vela X-1 ($M=1.77{\mathrm{\text{M}}}_{\odot },R=9.56\mathrm{\text{km}}$) for complete analysis of the solutions. For the same star, the well-behaved ranges are $1<n<5$ and $3<m<13$. However, beyond these limits, either the transversal sound speed becomes imaginary or violates the causality principle. Further, the critical part of our solution is that corresponding to every nonzero positive even value of $m$ yields zero values of all the physical quantities.