Cooperative adaptive cruise control (CACC) allows for short-distance automatic vehicle following using intervehicle wireless communication in addition to onboard sensors, thereby potentially improving road throughput. In order to fulfill performance, safety, and comfort requirements, a CACC-equipped vehicle platoon should be string stable, attenuating the effect of disturbances along the vehicl...

A framework for string-stability analysis is formulated in this paper. First, uniform string will be analyzed. We will then present analysis results on strings of mixed vehicles. A String-Stability Margin (SSM) index is defined in this paper to give a quantitative measurement of any ACC design. Simulation results using MATLAB and a microscopic traffic simulator will also be given to demonstrate...

Network systems and their control are highly important and appear in a variety of applications, including vehicle platooning and formation control. Especially vehicle platoons are highly investigated and an interesting problem that arises in this area is string stability, which broadly spoken means that a input signal amplifies unbounded as it travels through the vehicle string. However, variou...

Recent development in wireless technology enables communication between vehicles. The concept of cooperative adaptive cruise control (CACC)–which uses wireless communication between vehicles–aims at string stable behavior in a platoon of vehicles. “String stability” means any non-zero position, speed, and acceleration errors of an individual vehicle in a string do not amplify when they propagat...

Vacuum compactifications may suffer from instabilities under small perturbations or tunnel effects; both are difficult to analyze. In this paper we consider the issue a higher-dimensional perspective. We first look at how stability works for supersymmetric vacua, where it is widely expected hold. show that nucleation of brane bubbles in type II AdS forbidden probe approximation by simple argume...

We review the main results of our investigations motivated by tadpole potentials ten--dimensional strings with broken supersymmetry. While these are at best partial indications, it is hard to resist feeling that they do capture some lessons String Theory. For example, very lead weak-string-coupling cosmologies appear provide clues on onset inflation from an initial fast roll. The transition, if...

We review some aspects of the dramatic consequences supersymmetry breaking on string vacua. In particular, we focus issue vacuum stability in ten-dimensional models with broken, or without, supersymmetry, whose perturbative spectra are free tachyons. After formulating at stake, introduce their unified low-energy effective description and present a number solutions to classical equations motion....