Publications by Jean-Hubert Hours

An Alternating Trust Region Algorithm for Distributed Linearly Constrained Nonlinear Programs, Application to the Optimal Power Flow Problem

A novel trust region method for solving linearly constrained nonlinear programs is presented. The proposed technique is amenable to a distributed implementation, as its salient ingredient is an alternating projected gradient sweep in place of the Cauchy po ...

2017

Real-Time Distributed Algorithms for Nonconvex Optimal Power Flow

Colin Neil Jones, Georgios Stathopoulos, Jean-Hubert Hours, Yuejiang Liu

The optimal power flow (OPF) problem, a fundamental problem in power systems, is generally nonconvex and computationally challenging for networks with an increasing number of smart devices and real-time control requirements. In this paper, we first investi ...

2017

A Parametric Nonconvex Decomposition Algorithm for Real-Time and Distributed NMPC

Colin Neil Jones, Jean-Hubert Hours

A novel decomposition scheme to solve parametric nonconvex programs as they arise in Nonlinear Model Predictive Control (NMPC) is presented. It consists of a fixed number of alternating proximal gradient steps and a dual update per time step. Hence, the pr ...

2016

A parametric augmented Lagrangian algorithm for real-time economic NMPC

Colin Neil Jones, Jean-Hubert Hours, Harsh Ambarishkumar Shukla

In this paper, a novel optimality-tracking algorithm for solving Economic Nonlinear Model Predictive Control (ENMPC) problems in real-time is presented. Developing online schemes for ENMPC is challenging, since it is unclear how convexity of the Quadratic ...

IEEE2016

Decomposition Strategies for Nonconvex Problems, a Parametric Approach

Jean-Hubert Hours

This thesis deals with the development of numerical methods for solving nonconvex optimisation problems by means of decomposition and continuation techniques. We first introduce a novel decomposition algorithm based on alternating gradient projections and ...

EPFL2016

Constrained Spectrum Control

Colin Neil Jones, Melanie Nicole Zeilinger, Jean-Hubert Hours

A novel Nonlinear Model Predictive Control (NMPC) scheme is proposed in order to shape the harmonic response of constrained nonlinear systems. The salient ingredient is the short-time Fourier transform (STFT) of the system's output signal, which is constra ...

Institute of Electrical and Electronics Engineers2015

Parametric Polytope Reconstruction, an Application to Crystal Shape Estimation

Colin Neil Jones, Jean-Hubert Hours

In situ imaging techniques are a promising direction for monitoring the distribution of crystal sizes and shapes during a crystallization process. Nevertheless, no tractable method yet exists for estimating complex crystal shapes. In this paper, an in situ ...

Institute of Electrical and Electronics Engineers2014

An Augmented Lagrangian Coordination-Decomposition Algorithm for Solving Distributed Non-Convex Programs

Colin Neil Jones, Jean-Hubert Hours

A novel augmented Lagrangian method for solving non-convex programs with nonlinear cost and constraint couplings in a distributed framework is presented. The proposed decomposition algorithm is made of two layers: The outer level is a standard multiplier m ...

2014

A parametric multi-convex splitting technique with application to real-time NMPC

Colin Neil Jones, Jean-Hubert Hours

A novel splitting scheme to solve parametric multi-convex programs is presented. It consists of a fixed number of proximal alternating minimisations and a dual update per time step, which makes it attractive in a real-time Nonlinear Model Predictive Contro ...

2014

Spectrogram MPC: Enforcing hard constraints on system's output spectra

Colin Neil Jones, Melanie Nicole Zeilinger, Jean-Hubert Hours

A novel model predictive control (MPC) scheme that allows one to enforce hard constraints on the spectrum of a constrained system’s output signal is presented. The approach is based on a time-local analysis of the spectrum of output signals by means of the ...

Ieee Computer Soc2012