In this paper, we show how heterogeneous bidirectional vehicle strings can be modelled as port-Hamiltonian systems. Analysis of stability and string stability within this framework is straightforward and leads to a better understanding of the underlying problem. Nonlinear local control and additional integral action is introduced to design a suitable control law guaranteeing l2 string stability...

We derive and analyse, analytically and numerically, the equations for perturbations around the pulsating two-spin string soliton in AdS 5 × S 5. We show that the pulsation in S 5 indeed improves the stability properties of the two-spin string soliton in AdS 5 , in the sense that the more pulsation we have, the higher spin we can allow and still have stability.

We investigate the stability of the electroweak Z-string at high temperatures. Our results show that while finite temperature corrections can improve the stability of the Z-string, their effect is not strong enough to stabilize the Z-string in the standard electroweak model. Consequently, the Z-string will be unstable even under the conditions present during the electroweak phase transition. We...

We study the BPS spectrum of four dimensional N = 2 SU(2) theory with massive fundamental matters using the D3-brane probe. Since the BPS states are realized by string webs subject to the BPS conditions, we determine explicitly the configurations of such webs. It is observed that there appear BPS string webs with multiple of junctions corresponding to the fact that the curves of marginal stabil...

We give a detailed stability analysis of the Z-string in the standard electroweak model. We identify the mode that determines the stability of the string and numerically map the region of parameter space where the string is stable. For sin2 θW = 0.23, we find that the strings are unstable for a Higgs mass larger than 23GeV. Given the latest constraints on the Higgs mass from LEP, this shows tha...

One of the most important issues in longitudinal control of vehicles in automated highway systems (AHS) is string stability, that is, the attenuation of spacing errors as they propagate upstream the platoon. In this paper we use a mass-spring-damper system as a simpliied framework for string stability analysis and study the properties of several longitudinal control schemes which have been prop...

Over the last few decades, congested traffic network have become a serious problem in many countries. Congestions result in time losses, increase of fuel consumption and also raise the risk of accidents. Intelligent transportation systems may contribute to mitigate such problems. Advancement together with the reduction in cost of embedded computing, on-board vehicle sensors and wireless communi...