Discover how longitudinal data helps analyze financial trends, business risks, and economic changes with repeated observations of the same subjects over time.

Negative refraction of elastic waves has been studied and experimentally demonstrated in three- and two-dimensional phononic crystals, but Bragg scattering is impractical for low-frequency wave ...

Waves transfer energy from one place to another. Light from the Sun travels through space and through the atmosphere, transferring energy to the Earth and other planets. Sound travels from a ...