A low-profile speaker assembly comprises a substrate and a substantially plan piezoelectric element disposed in a plane substantially parallel to the substrate and mechanically connected to the substrate at one or more edges. Along these lines, when an IT professional monitors a computing environment through the device monitoring system, the device monitoring system stores alerting rules sets for that computing environment in a database. The detected coherent emissions are processed with a matched filter to determine presence of a target object within the portal. A display section is provided on the case for transmitting the light, radiated from the light source, to be visually checked on the external side. A dielectric layer and a conductive capacitor electrode layer are disposed operably proximate the first and second containers.