A case study in the future challenges in electricity grid infrastructure

The generation by renewables and the loading by electrical vehicle charging imposes severe challenges in the redesign of today's power supply systems. Indeed, accomodating these emerg- ing power sources and sinks requires traditional power systems to evolve from rigid centralized unidirectional architectures to intelligent decentralized entities...

A hybrid-optimization method for large-scale non-negative full regualarization in image restoration

We describe a new hybrid-optimization method for solving the full-regularization problem of comput- ing both the regularization parameter and the corresponding regularized solution in 1-norm and 2-norm Tikhonov regularization with additional non-negativity constraints. The approach combines the simu- lated annealing technique for global...

Evaluation MUMIE - Online math education aerospace engineering 2010-2011

This report gives an overview of the development and experiences of using Mumie [1] at TU Delft during the academic year 2010-2011. Mumie is an e-learning platform that can be used for mathematical courses and acquired the interest of TU Delft at the beginning of 2009 in order to be used in their first years mathematical courses, in particular...

Flexible and multi-shift induced dimension reduction algorithms for solving large sparse linear systems

We give two important generalizations of the Induced Dimension Reduction (IDR) approach for the solution of linear systems. We derive a flexible and a multi-shift Quasi-Minimal Residual IDR (QMRIDR) variant. Numerical examples are presented to show the effectiveness of these new IDR variants compared to existing ones and to other Krylov subspace...

Computational and sensitivity aspects of eigenvalue-based methods for the large-scale trust-region subproblem

The trust-region subproblem of minimizing a quadratic function subject to a norm constraint arises in the context of trust-region methods in optimization and in the regularization of discrete forms of ill-posed problems, including non-negative regularization by means of interior-point methods. A class of efficient methods and software for...

Optimal configuration of future electricity grid

This paper considers the scenario of a big new energy source connecting to an existing network of generators and loads. To be able to maintain such a network at the correct settings, the well known load flow equations have to be solved. Since existing software has trouble with solving the load flow equations in the scenario of a very large...

Counteracting ring formation in rotary kilns

Avoiding the formation of rings in rotary kilns is an issue of primary concern to the cement production industry. We developed a numerical combustion model that revealed that in our case study rings are typically formed in zones of maximal radiative heat transfer. This local overheating causes the overproduction of the liquid phase of the...