A new base of wind turbine noise measurement data and its application for a systematic validation of sound propagation models

Extensive measurements in the area of wind turbines were performed in order to validate a sound propagation model which is based on the Crank–Nicolson parabolic equation method. The measurements were carried out over a flat grass-covered landscape and under various environmental conditions. During the measurements, meteorological and wind turbine performance data were acquired and acoustical data sets were recorded at distances of 178, 535 and 845 m from the wind turbine. By processing and analysing the measurement data, validation cases and input parameters for the sound propagation model were derived. The validation includes five groups that are characterised by different sound propagation directions, i.e. downwind, crosswind and upwind conditions in varying strength. In strong upwind situations, the sound pressure levels at larger distances are overestimated because turbulence is not considered in the modelling. In the other directions, the model reproduces the measured sound propagation losses well in the overall sound pressure level and in the third octave band spectra. As in the recorded measurements, frequency-dependent maxima and minima are identified, and losses generally increase with increasing distance and frequency. The agreement between measured and modelled sound propagation losses decreases with distance. The data sets used in the validation are freely accessible for further research

WindGISKI : Kann KI neue Flächen für Windenergieanlagen finden?

[no abstract available

Wie entsteht Lärm bei Windenergieanlagen? : Untersuchungen zu Schallausbreitung und Schallwahrnehmung

[no abstract available

A 2050 Vision for Energy-efficient and CO2-free Urban Logistics

The energy strategy 2050 of Switzerland is aiming at a substantial reduction of the consumption of not renewable energy and of energy sources, which are harmful for the climate, the environment and humans. The research project “Energy efficient and CO2-free Urban Logistics” aims at estimating and evaluating the potential of a more efficient use of energy, a reduction of CO2-emissions and the substitution of non-renewable energy resources regarding urban logistics in Switzerland. Possible developments in urban logistics and their impact on energy consumption and CO2-emission are shown in a scenario analysis. Furthermore a vision 2050 has been developed which fulfils the challenging targets for an “Energy efficient and CO2-free Urban Logistics” in Switzerland. The scenario analysis was completed in October 2016 and the vision has been carried out between November 2016 and June 2017. Based on the vision an action plan will be developed until end of 2017. Document type: Part of book or chapter of boo

A concerted action of HNF4alpha and HNF1alpha links hepatitis B virus replication to hepatocyte differentiation.

International audienceHepatitis B virus (HBV) is an important human pathogen, which targets the liver extremely efficient, gaining access to hepatocytes by a so far unknown receptor and replicating in a hepatocyte-specific fashion. Cell differentiation seems to determine HBV replication. We here show that the level of hepatocyte differentiation, as indicated by hepatocyte polarization and metabolic activity, is closely correlated to the transcription of the HBV RNA pregenome. Pregenome transcription determined the level of HBV replication in various cell lines of hepatocellular origin and in primary human hepatocytes. A variety of hepatocyte-enriched nuclear factors have been described to regulate transcription of the pregenome, but it remained unknown which factors link HBV replication to hepatocyte differentiation. We determined that high expression levels of HNF4alpha but not its potential cofactors or other hepatocyte-enriched transcription factors were essential for efficient HBV replication, and link it to hepatocyte differentiation. HNF1alpha contributed to the control of HBV replication because it regulated the expression of HNF4alpha. Thus, a concerted action of HNF4alpha and HNF1alpha, which also determines morphological and functional differentiation of hepatocytes, links HBV replication to hepatocyte differentiation