Rietveld originals: Handle with care!

The work of architect Gerrit Th. Rietveld (1888 – 1964) is appreciated throughout the world. Many of the well-known buildings he designed have survived to the present. Some have been restored or refurbished, depending on the condition of the building, current needs of the building users, etc. Rietveld himself had a very clear vision about...

Public space: Open to everybody – but how? Street art as a threat or a prospect

Workshop 2. Public space interventions Abstract Street art, a form of local urban intervention, encounters strong oppositions from many planners. Making an imprint in public space is, for the most part, only legal if you advertise or if the municipality commissions you. By unlawfully taking up space in the city, streets artists challenge the...

Towards an algebraic multigrid method for tomographic image reconstruction -- improving convergence of ART

In this paper we introduce a multigrid method for sparse, possibly rank-deficient and inconsistent least squares problems arising in the context of tomographic image reconstruction. The key idea is to construct a suitable AMG method using the Kaczmarz algorithm as smoother. We first present some theoretical results about the correction step and...

Artful Judgements: A psychological inquiry into aesthetic preference for visual patterns