Publications related to A Sparsity Measure For Echo Density Growth In General Environments

Achieving Optimal Performance With Data-Driven Frequency-Based Control Synthesis Methods

Alireza Karimi, Philippe Louis Schuchert

Frequency Response Function (FRF)-based control synthesis methods for Linear Time-Invariant (LTI) systems have been widely used in control theory and industry. Recently, there has been renewed interest in these methods, employing numerical optimization too ...

Ieee-Inst Electrical Electronics Engineers Inc2023

Data-driven IQC-Based Robust Control Design for Hybrid Micro-disturbance Isolation Platform

Alireza Karimi, Elias Sebastian Klauser, Vaibhav Gupta

A novel approach for robust controller synthesis, which models uncertainty as an elliptical set, is proposed in the paper. Given a set of frequency response functions of linear time-invariant (LTI) multiple-input multiple-output (MIMO) systems, the approac ...

IEEE2023

Systematic extraction of a control-oriented model from perturbative experiments and SOLPS-ITER for emission front control in TCV

Mirko Wensing, Olivier Claude Martin Février, Artur Perek

Systematic extraction of locally valid dynamic models from experiments is necessary for controller design and the validation of high fidelity models. This paper describes the extraction of a dynamic model in the form of a transfer function, giving the dyna ...

IOP Publishing Ltd2022

HP - A code for the calculation of Hubbard parameters using density-functional perturbation theory

Nicola Marzari, Matteo Cococcioni, Iurii Timrov

We introduce HP, an implementation of density-functional perturbation theory, designed to compute Hubbard parameters (on-site U and inter-site V ) in the framework of DFT+U and DFT+U+V. The code does not require the use of computationally expensive superce ...

ELSEVIER2022

Self-consistent Hubbard parameters from density-functional perturbation theory in the ultrasoft and projector-augmented wave formulations

Nicola Marzari, Matteo Cococcioni, Iurii Timrov

The self-consistent evaluation of Hubbard parameters using linear-response theory is crucial for quantitatively predictive calculations based on Hubbard-corrected density-functional theory. Here, we extend a recently introduced approach based on density-fu ...

AMER PHYSICAL SOC2021

A Vibrational Technique for in vitro Intraoperative Prosthesis Fixation Monitoring

Kamiar Aminian, Hooman Dejnabadi, Seyed Abdolmajid Yousefsani

Objective: In this paper, a new vibrational modal analysis technique was developed for intraoperative cementless prosthesis fixation evaluation upon hammering. Methods: An artificial bone (Sawbones)-prosthesis system was excited by sweeping of a sine signa ...

2020

A Note on BIBO Stability

Michaël Unser

The statements on the BIBO stability of continuoustime convolution systems found in engineering textbooks are often either too vague (because of lack of hypotheses) or mathematically incorrect. What is more troubling is that they usually exclude the identi ...

2020

Instability of a thin viscous film flowing under an inclined substrate: the emergence and stability of rivulets

Gioele Mariano Nicolò Balestra, François Gallaire, Gaëtan Pierre Clément Lerisson, Pier Giuseppe Ledda

We study the pattern formation of a thin film flowing under an inclined planar substrate. The phenomenon is studied in the context of the Rayleigh-Taylor instability using the lubrication equation. Inspired by experimental observations, we numerically stud ...

Cambridge University Press2020

Frequency fluctuations in nanomechanical silicon nitride string resonators

Luis Guillermo Villanueva Torrijo, Alper Demir

High quality factor (Q) nanomechanical resonators have received a lot of attention for sensor applications with unprecedented sensitivity. Despite the large interest, few investigations into the frequency stability of high-Q resonators have been reported. ...

AMER PHYSICAL SOC2020

Seek and learn: Automated identification of microevents in animal behaviour using envelopes of acceleration data and machine learning

Kamiar Aminian, Hooman Dejnabadi, Pritish Chakravarty

Animal‐borne accelerometers have been used across more than 120 species to infer biologically significant information such as energy expenditure and broad behavioural categories. While the accelerometer’s high sensitivity to movement and fast response time ...

2020

Linear Response Theory and Green-Kubo Relations for Active Matter

Ignacio Pagonabarraga Mora, Sara Dal Cengio

We address the question of how interacting active systems in a nonequilibrium steady state respond to an external perturbation. We establish an extended fluctuation-dissipation theorem for active Brownian particles (ABP), which highlights the role played b ...

2019

A Robust Data-Driven Controller Design Methodology With Applications to Particle Accelerator Power Converters

Alireza Karimi, Achille Nicoletti, Michele Martino

A new data-driven approach using the frequency response function (FRF) of a system is proposed for designing robust-fixed structure digital controllers for particle accelerators' power converters. This design method ensures that the dynamics of a system ar ...

2019

Design and Validation of a Compact Embedded Photometric Device for Real-time Daylighting Computing in Office Buildings

Jean-Louis Scartezzini, Jérôme Henri Kämpf, Yujie Wu

Studies have shown that the exposure to daylight can have substantial visual/non-visual benefits for building occupants. To optimise daylighting provision while maintaining a comfortable visual environment, daylighting control systems have been investigate ...

2019

Imitation, Proximity, and Growth - A Collective Swarm Dynamics Approach

Max-Olivier Hongler, Fariba Hashemi, Olivier Gallay

This paper is based on the premise that economic growth is driven by an interplay between innovation and imitation in an economy composed of interacting ̄rms operating in a stochastic environment. A novel approach to modeling imitation is presented based o ...

2019

Non-linear transfer function identification of pressure probes using Siren Disks

Jürg Alexander Schiffmann, Karim Magdi Zakaria Abdelrahman Shalash, Fatma Ceyhun Sahin

This article presents a Siren Disk proof of concept for the dynamic excitation of pressure probes, and a method to reconstruct distorted signals due to pneumatic channels. Constraints in sensor installation require placing a pressure transducer distant fro ...

2018

A Data-Driven Frequency-Domain Approach for Robust Controller Design via Convex Optimization

Achille Nicoletti

The objective of this dissertation is to develop data-driven frequency-domain methods for designing robust controllers through the use of convex optimization algorithms. Many of today's industrial processes are becoming more complex, and modeling accurate ...

EPFL2018

A Data-Driven Fixed-Structure Control Design Method with Application to a 2-DOF Gyroscope

Alireza Karimi, Christoph Manuel Kammer

This paper presents the practical aspects and application of a novel data-driven, fixed-structure, robust control design method. Only the frequency response data of the system is needed for the design, and no parametric model is required. The method can be ...

IEEE2018

Absolute/convective secondary instabilities and the role of confinement in free shear layers

François Gallaire, Saviz Mowlavi, Cristobal Manuel Arratia Martinez

We study the linear spatiotemporal stability of an infinite row of equal point vortices under symmetric confinement between parallel walls. These rows of vortices serve to model the secondary instability leading to the merging of consecutive (Kelvin-Helmho ...

2018

Reliability Mechanisms for Controllers in Real-Time Cyber-Physical Systems

Maaz Mashood Mohiuddin

Cyber-physical systems (CPSs) are real-world processes that are controlled by computer algorithms. We consider CPSs where a centralized, software-based controller maintains the process in a desired state by exchanging measurements and setpoints with proces ...

EPFL2018

Rise time reduction of thermal actuators operated in air and water through optimized pre-shaped open-loop driving

Georg Fantner, Nahid Hosseini, Tom Larsen

Electrothermal actuators have many advantages compared to other actuators used in micro-electro-mechanical systems (MEMS). They are simple to design, easy to fabricate and provide large displacements at low voltages. Low voltages enable less stringent pass ...

2017