Abstract: System and method for automatically broadcasting voice-based prompt warnings toward an embarkation and/or disembarkation location at which passengers such as students and others may or will be present. The method is multi-model providing voice messages during an approach mode, a stop mode and a standby mode. Recorded human voice messages are employed for the prompt and are the recorded voices of one or more people having voice characteristics generally recognizable by the passengers to an extent effective to supplement the function of the immature prefrontal cortex.

Abstract: A method is presented to allow a quick, positive attachment of a fastener to a module body. The module body and the fastener each have interrupted screw sections to connect with a partial turn. A latching mechanism, such as a pawl and cog arrangement, can provide a positive lock when the interrupted screw threads are fully engaged. A mechanism such as tab lever can be used to disengage the positive lock to easily remove the module. The controlled traverse over a known thread pitch allows the use of a compressible face on the fastener with a fixed compression and a repeatable, tight connection.

Abstract: A controller, either a microprocessor or finite state machine, is used to generate a pulse train whose frequency and duty cycle can be varied to alter the frequency and amplitude of the output of a driven audio transducer. The ability to control both frequency and amplitude allows programmatic synthesis of many audio effects such as steady tones, warbles, beeps, sirens and chimes with no hardware or circuit changes. The transducer can be a piezoelectric bender or a speaker. The output of the controller controls a switch that builds current in an inductor when the switch is on. When the switch is turned off, the energy stored in the inductor is dumped into the audio transducer, either directly or through intermediate capacitor storage. This allows the generation of voltages across the transducer many times the supply voltage.

Abstract: An apparatus for creating a framework for the creation, editing, signing and signature verification of multiple documents includes a master, or cover, document as a holder and display source for the subdocuments created within the cover document. The cover document is protected against direct modification with the possible exception of the addition of comments that do not affect digital signatures in the cover document. Access to the subdocuments for editing, signature generation and signature verification is through a menu associated with the cover document. A method of creating a hierarchy of approval signatures on the cover document encompassing subdocuments and nested approval signatures is described.