background and objective: sleepiness is one of the important factors in motor vehicle accidents, especially in commercial drivers (cds). obstructive sleep apnea (osa) has an important role in developing sleepiness. the stop-bang questionnaire is used in medical examinations of commercial drivers in iran by law. this study aimed to investigate the judgment that drivers prefer not to report their...

classical control methods such as pontryagin maximum principle and bang-bang principle and other methods are not usually useful for solving opti-mal control systems (ocs) specially optimal control of nonlinear systems (ocns). in this paper, we introduce a new approach for solving ocns by using some combination of atomic measures. we define a criterion for controllability of lumped nonlinear con...

We study numerically the inhomogeneous pre-big-bang inflation in a spherically symmetric space-time. We find that a large initial inhomogeneity suppresses the onset of the pre-big-bang inflation. We also find that even if the pre-big-bang inflationary stage is realized, the initial inhomogeneities are not homogenized. Namely, during the pre-big-bang inflation “hairs”(irregularities) do not fall...

Discontinuous dynamical systems arise in a large number of applications. In optimal control problems, open-loop bang-bang controllers switch discontinuously between extremum values of the bounded inputs to generate minimum-time trajectories from one state to another. Thermostats implement closed-loop bang-bang controllers to regulate room temperature. In nonsmooth mechanics, the evolution of ri...

A discrete-time periodic model with bang-bang feedback control is investigated. It is shown that each solution tends to one of four different types of limit 2-cycles. Furthermore, the accompanying initial regions for each type of solutions can be determined. When a threshold parameter is introduced in the bang-bang function, our results form a complete bifurcation analysis of our control model....