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Conditions for Carbonation of Silica Fume Concretes

This article outlines an experimental and numerical study on the pozzolanic interaction limits for carbonation of silica fume concretes. For this purpose cylinders of 8 types of High-Performance Concrete were cast. Carbonation and weight losses were studied parallel. An indirect method was used to measure carbonation; i.e. carbonation shrinkage was observed. The age of concrete at start of carbona

Evaluation of an Outdoor-to-In-Car Radio Channel with a Four-Antenna Handset and a User Phantom

Based on static outdoor channel measurements we evaluate the influence of a vehicle on the MIMO radio channel, from a base station antenna array, to a multiple antenna handset in the hand of a user placed inside a test car. The measurement scenario is chosen to mimic a 2.6 GHz (LTE) macro-cell urban or rural scenario with two locations and orientations of the car, one at an open parking lot with a

Molecular Mapping of Movement-Associated Areas in the Avian Brain: A Motor Theory for Vocal Learning Origin

Vocal learning is a critical behavioral substrate for spoken human language. It is a rare trait found in three distantly related groups of birds-songbirds, hummingbirds, and parrots. These avian groups have remarkably similar systems of cerebral vocal nuclei for the control of learned vocalizations that are not found in their more closely related vocal non-learning relatives. These findings led to