Abstract: Use of the conditioning number k(F) = ∥ F ∥ • ∥ F−1 ∥ where F is a symmetric matrix related to the controllability (observability) matrix is suggested as basis for index of controllability ...

Abstract: To find the optimum control law u = u(x) for the process ẋ = f(x, u), the Hamiltonian H = p′ f is formed. The optimum control law can be expressed as u = u* = σ(p, x), where u* ...

Abstract: The problem of minimizing both the in-flight bending moments as well as the terminal drift of a flexible vehicle is considered. The performance criterion V(T) = 12y2(T)+k2 tT M2(ξ)dξ, where ...

Abstract: Two new models for “slip-stick” friction are presented. One, called the “bristle model,” is an approximation designed to capture the physical phenomenon of sticking. This model is relatively ...