Data set on the effectiveness of flip teaching on engineering students' performance in the physics lab compared to Traditional Methodology.

This paper shows the data of the Flip Teaching and Traditional Methodology on the laboratory practice in two subjects, Physics and Electricity, of a technical degree. The laboratory and final grades of these subjects were shown in four consecutive years. The characteristics of all four years were quite similar, except that the Traditional teaching Methodology (TM) was used in two, while Flip Teaching methodology (FT) was applied in the other two.

Large two-dimensional sonic band gaps.

We show that absolute sonic band gaps produced by two-dimensional square and triangular lattices of rigid cylinders in air can be increased by reducing the structure symmetry. In the case of square lattices, symmetry reduction is achieved by a smaller diameter cylinder placed at the center of each unit cell. For triangular lattices the reduction is achieved by decreasing the diameter of the cylinder at the center of the hexagons in the lattice.

Refractive acoustic devices for airborne sound.

We show that a sonic crystal made of periodic distributions of rigid cylinders in air acts as a new material which allows the construction of refractive acoustic devices for airborne sound. It is demonstrated that, in the long-wave regime, the crystal has low impedance and the sound is transmitted at subsonic velocities. Here, the fabrication and characterization of a convergent lens are presented.

Reflectance properties of two-dimensional sonic band-gap crystals.

An analysis of the reflectance of sonic band-gap crystals consisting of square arrays of rigid cylinders in air is presented. The standing wave formed in front of the structures is studied both experimentally and theoretically. Experiments have been performed with a mobile robotized microphone that obtains pressure maps on the plane perpendicular to the axes of the cylinders.