Robustness of Network Controllability with Respect to Node Removals Based on In-Degree and Out-Degree

Network controllability and its robustness have been widely studied. However, analytical methods to calculate network controllability with respect to node in- and out-degree targeted removals are currently lacking. This paper develops methods, based on generating functions for the in- and out-degree distributions, to approximate the minimum...

The Recoverability of Network Controllability

Network recoverability refers to the ability of a network to recover to a desired performance level after suffering topological perturbations such as link failures. The minimum number of driver nodes is a typical metric to denote the network controllability. In this paper, we propose closed-form analytic approximations for the minimum number of...

The effect of landing gear implementation on Flying V aerodynamics, stability and controllability

Initially conceptualised by Benad in 2015 as a highly swept flying wing aircraft to replace the A350-900, the Flying V design has since been refined in several later studies at both Airbus and TU Delft. The initial aerodynamic efficiency gain estimation was refined by Faggiano and Rubio-Pascual, confirming the interest of the solution. To...

Structural Controllability of Switching Max-Plus Linear Systems

We introduce a framework for studying controllability properties of discrete-event systems modelled as switching max-plus linear systems. In this framework, we generalise the notion of structural controllability to include the switching phenomenon. Such models provide an additional discrete input to change the synchronisation and/or ordering...

Equivalence in Experimental Source Characterisation

Transfer Path Analysis methods allow to describe the propagation of vibrations from an active source to a passive receiving structure. These methods are based in the experimental modelling domain, where the dynamics of the problem are described based on empirical observations from an experiment, as opposed to a numerical model based on natural...

On the use of equivalent forces for structural health monitoring based on joint input-state estimation algorithms

For the monitoring of large structures where the loading is typically characterized by large uncertainties in temporal and/or spatial evolution, algorithms capable of estimating a set of response driving equivalent forces are strongly desired. In this context, several Kalman-type coupled input-state and coupled input-state-parameter filters...

A Controllability Approach for Resonant Compliant Systems: Applied to a Flapping Wing Micro Air Vehicle

This thesis studies a controllability approach for general resonant compliant systems. These systems exploit resonance to obtain a specific dynamic response at relatively low actuation power. This type of systems is often lightweight, is scalable and minimizes frictional losses through the use of compliant hinges. Some insect-inspired Flapping...

Use of reduced-order models in well control optimization

Many aspects of reservoir management can be expected to benefit from the application of computational optimization procedures. The focus of this review paper is on well control optimization, which entails the determination of well settings, such as flow rates or bottom hole pressures, that maximize a particular objective function. As is the case...

Controllability and observability in two-phase porous media flow

Reservoir simulation models are frequently used to make decisions on well locations, recovery optimization strategies etc. The success of these applications is, among other aspects, determined by the controllability and observability properties of the reservoir model. In this paper it is shown how the controllability and observability of two...

A system-theoretical approach to selective grid coarsening of reservoir models

From a system-theoretical point of view and for a given configuration of wells, there are only a limited number of degrees of freedom in the input–output dynamics of a reservoir system. This means that a large number of combinations of the state variables (pressure and saturation values) are not actually controllable and observable from the...

Model Structure Analysis of Model-based Operation of Petroleum Reservoirs

The demand for petroleum is expected to increase in the coming decades, while the production of petroleum from subsurface reservoirs is becoming increasingly complex. To meet the demand petroleum reservoirs should be operated more efficiently. Physics-based petroleum reservoir models that describe the flow in subsurface porous media can play an...

Controllability, observability and identifiability in single-phase porous media flow

Over the past few years, more and more systems and control concepts have been applied in reservoir engineering, such as optimal control, Kalman filtering, and model reduction. The success of these applications is determined by the controllability, observability, and identifiability properties of the reservoir at hand. The first contribution of...

Dynamics of flexible spacecraft: the internal balancing approach towards mathematical model order reduction

Mathematical models of the dynamics of spacecraft are needed to carry out numerical simulations, to gain insight into the characteristics of the spacecraft dynamics, and to synthesize control algorithms suitable for online system Identification, estimation, and control. Increases in size and mechanical complexity of spacecraft result in...

Failures in advanced flight control systems of future transport aircraft

Future transport aircraft will be different from to-day's in that they will be designed to be statically neutrally stable or even unstable to improve economics, while the stability will be provided by means of a fly-by-wire flight control system. Since this system will be flight critical it is necessary to develop a philosophy on the treatment...