Abstract: Systems and methods for detecting a subsurface cavity. A source applies a force to ground under inspection and a plurality of sensors coupled to the ground detect resulting surface waves. A processor is configured to extract phase and frequency components of the acquired seismic data, identify a phase shift in surface waves in the ground under inspection based on the extracted phase and frequency components, and determine one or more physical characteristics of a subsurface cavity based on the identified phase shift.

Abstract: The vacuum-formed plastic lid for a large disposable container of liquids includes a pouring spout formed into the rim of the lid. A portion of the lid can be torn out, and the liquid poured through the hole. A well in the lid constitutes a receptacle for storing and carrying a number of empty, smaller, drinking cups. The lid includes a ridge, and two cuts, one either side of the ridge. When a person squeezes the ridge, the cuts spread over the ridge, until they meet. The ridge constitutes also a handle, by which the person can manipulate and remove the tear-out portion.