The effects of forced relocations on improvements of the housing situation: A case study in four Dutch cities (draft version)

Urban restructuring takes place in numerous cities in Western European countries, often in the form of the demolition of relatively cheap dwellings and replacement by new, more expensive dwellings. This phenomenon has been studied extensively. Especially the effects of urban restructuring on the restructured areas themselves have been examined. Much less is known about the residents that had to relocate because of urban restructuring measures like demolition and intensive renovation. This paper therefore focuses on the question whether and why residents improve their housing situation. Using data from four Dutch cities we first make clear how the old and new housing situation differ by focusing both on objective and evaluated changes. Then, explanations are offered for the extent to which residents do or do not experience changes, with respect to dwelling as well as neighbourhood aspects. We found that (a) displaced residents both experience objective and evaluated improvements of their housing situation; (b) that in contrast to objective improvements, evaluated improvements are hardly related to individual and household characteristics; (c) evaluated improvements can be attributed to improved characteristics of the dwelling and neighbourhood; and (d) that increased satisfaction with the dwelling and neighbourhood are strongly related

Observation of Landau levels at the InAs(110) surface by scanning tunneling spectroscopy

Contains fulltext : 28857.pdf (publisher's version ) (Open Access

Semiconductor band switching by charging a small grain with a single electron

Contains fulltext : 28858.pdf (publisher's version ) (Open Access

Structural Dynamic Topology Optimisation of a Direct-Drive Single Bearing Wind Turbine Generator

Reducing weight of off-shore wind turbine nacelles is currently a key driver of innovation within the wind turbine industry. Weight reduction will not only lead to smaller loads and thus smaller towers of the turbine, but also reduce logistic costs during the turbine’s installation. This holds even more so for off-shore turbines, the costs related to installing a turbine is a substantial investment compared to the operational cost. A reduced nacelle weight will, subsequently, lead to reduced cost of wind energy. For direct-drive turbines, the generator is one of the heaviest parts of the wind turbine nacelle. Due to the low rotational speed of the generator, the loads are especially high in this type of turbine, which increases the necessary structural mass of the rotor. Recently, designed flexibility has been identified as one approach to achieve weight reduction. However, reducing the weight of the support structure has proven difficult, due to the complex pattern of dynamic excitation forces. Until now, density based topology optimisation has hardly been employed for the design of wind turbine parts. This publication investigates the possible weight reduction which results from applying this method to the support structure of the generator rotor. As a first step, crucial excitation frequencies and spatial force distributions that are generated by the magnetic field are presented. Then the topology optimisation is executed using a modal and a harmonic approach, applying the identified force distributions.Precision and Microsystems EngineeringMechanical, Maritime and Materials Engineerin

Effect of topological imperfections on the electro-mechanical properties of structured piezoelectric particulate composites

A novel method based on the Virtual Particle Mori–Tanaka (VPMT) is developed to predict the effective electro-elastic properties, d33 and g33, of structured piezoelectric particulate composites with improved accuracy by means of a single parameter related to the spatial distribution of imperfectly aligned rod-like PZT particles. The VPMT method is found to have excellent prediction capabilities for idealized particle configurations. Several new correction functions are presented to capture the drop in piezoelectric composite’s electro-elastic properties as a function of topological imperfections. These imperfections are related to longitudinal and lateral inter-particle spacings and the topology of the chain like structures themselves. The functions are evaluated in detail and show physically consistent behaviour.Novel Aerospace MaterialsAerospace Structures & MaterialsSupport Aerospace Materials & Manufacturin