Contents

Preface

Associate Editors

Website

PART 1. LINEAR SYSTEMS

Problem 1.1. Stability and composition of transfer functions

Problem 1.2. The realization problem for Herglotz-Nevanlinna functions

Problem 1.3. Does any analytic contractive operator function on the polydisk have a dissipative scattering nD realization?

Problem 1.4. Partial disturbance decoupling with stability

Problem 1.5. Is Monopoli’s model reference adaptive controller correct?

Problem 1.6. Model reduction of delay systems

Problem 1.7. Schur extremal problems

Problem 1.8. The elusive iff test for time-controllability of behaviors

Problem 1.9. A Farkas lemma for behavioral inequalities

Problem 1.10. Regular feedback implementability of linear differential behaviors

Problem 1.11. Riccati stability

Problem 1.12. State and first order representations

Problem 1.13. Projection of state space realizations

PART 2. STOCHASTIC SYSTEMS

Problem 2.1. On error of estimation and minimum of cost for wide band noise driven systems

Problem 2.2. On the stability of random matrices

Problem 2.3. Aspects of Fisher geometry for stochastic linear systems

Problem 2.4. On the convergence of normal forms for analytic control systems

PART 3. NONLINEAR SYSTEMS

Problem 3.1. Minimum time control of the Kepler equation

Problem 3.2. Linearization of linearly controllable systems

Problem 3.3. Bases for Lie algebras and a continuous CBH formula

Problem 3.4. An extended gradient conjecture

Problem 3.5. Optimal transaction costs from a Stackelberg perspective

Problem 3.6. Does cheap control solve a singular nonlinear quadratic problem?

Problem 3.7. Delta-Sigma modulator synthesis

Problem 3.8. Determining of various asymptotics of solutions of nonlinear timeoptimal problems via right ideals in the moment algebra

Problem 3.9. Dynamics of principal and minor component flows

PART 4. DISCRETE EVENT, HYBRID SYSTEMS

Problem 4.1. L2-induced gains of switched linear systems

Problem 4.2 The state partitioning problem of quantised systems

Problem 4.3. Feedback control in flowshops

Problem 4.4. Decentralized control with communication between controllers

PART 5. DISTRIBUTED PARAMETER SYSTEMS

Problem 5.1. Infinite dimensional backstepping for nonlinear parabolic PDEs

Problem 5.2. The dynamical Lame system with boundary control: on the structure of reachable sets

Problem 5.3. Null-controllability of the heat equation in unbounded domains

Problem 5.4. Is the conservative wave equation regular?

Problem 5.5. Exact controllability of the semilinear wave equation

Problem 5.6. Some control problems in electromagnetics and fluid dynamics

PART 6. STABILITY, STABILIZATION

Problem 6.1. Copositive Lyapunov functions

Problem 6.2. The strong stabilization problem for linear time-varying systems

Problem 6.3. Robustness of transient behavior

Problem 6.4. Lie algebras and stability of switched nonlinear systems

Problem 6.5. Robust stability test for interval fractional order linear systems

Problem 6.6. Delay-independent and delay-dependent Aizerman problem

Problem 6.7. Open problems in control of linear discrete multidimensional systems

Problem 6.8. An open problem in adaptative nonlinear control theory

Problem 6.9. Generalized Lyapunov theory and its omega-transformable regions

Problem 6.10. Smooth Lyapunov characterization of measurement to error stability

PART 7. CONTROLLABILITY, OBSERVABILITY

Problem 7.1. Time for local controllability of a 1-D tank containing a fluid modeled by the shallow water equations

Problem 7.2. A Hautus test for infinite-dimensional systems

Problem 7.3. Three problems in the field of observability

Problem 7.4. Control of the KdV equation

PART 8. ROBUSTNESS, ROBUST CONTROL

Problem 8.1 H∞ - norm apporoximation

Problem 8.2. Noniterative computation of optimal value in H∞ control

Problem 8.3. Determining the least upper bound on the achievable delay margin

Problem 8.4. Stable controller coefficient perturbation in floating point implementation

PART 9. IDENTIFICATION, SIGNAL PROCESSING

Problem 9.1. A conjecture on Lyapunov equations and principal angles in subspace identification

Problem 9.2. Stability of a nonlinear adaptive system for filtering and parameter estimation

PART 10. ALGORITHMS, COMPUTATION

Problem 10.1 Root-dusting for multivariate polynomials and robust stability analysis

Problem 10.2. When is a pair of matrices stable?

Problem 10.3. Freeness of multiplicative matrix semigroups

Problem 10.4. Vector-valued quadratic forms in control theory

Problem 10.5. Nilpotent bases of distributions

Problem 10.6. What is the characteristic polynomial of a signal flow graph?

Problem 10.7. Open problems in randomized μ analysis