Abstract: A system for synchronizing the audio or video and visual components of a presentation through a web-based application. The user listens to an audio or video recording file while viewing a series of visual presentation components, such as individual slides, and clicking on or otherwise indicating when a particular component of the visual presentation should start corresponding with the audio or video recording. The system keeps track of the timing of the user clicks or actions, and saves the presentation as a synchronized audio/video and visual presentation available for viewing and listening.

Abstract: A user interface system for allowing users to initiate events comprises: a plurality of markers each having a marker identity; a plurality of portable readers each having a reader identity and arranged to read said marker identities from adjacent markers, and at least one base station arranged to communicate with said readers in a wireless manner, wherein at least one reader is provided with actuation means which when actuated by a user causes the reader identity of the reader and the marker identity of an adjacent marker to be transmitted by the reader to said base station, so as to cause, for at least one of said markers, said base station to initiate, directly or indirectly, an action which is at least partly determined by the reader identity of said reader.

Abstract: A system for monitoring the presence of persons within a zone, the system comprising: one or more remotely detectable markers, each capable of being carried by a person; a first sensor arrangement capable of identifying the presence of the body of at least one person within the zone; a second sensor arrangement capable of identifying the presence of at least one marker within the zone; and a processing arrangement responsive to the first sensor arrangement and the second sensor arrangement to generate an alarm signal if the first sensor arrangement identifies the presence of a body without the second sensor arrangement identifying a marker corresponding in a first predetermined manner to that body.

Abstract: A technique is provided for providing total flexibility of control of any desired operation within an environment where personnel work, such as an office suite. The location of transponders is determined by a location system. A user arbitrarily selects a convenient region for controlling an operation and the location system registers this in a memory. The location system then determines the position of each transducer and, when a transducer is within one of the selected regions, the location system responds by controlling the operation. For example, a region may be selected entirely arbitrarily so as to control room lighting.

Abstract: A location system comprises a plurality of transponders whose locations are detectable by a base system. The base system interrogates (51-55) the transponders one at a time in accordance with a schedule of consecutive time slots. In response to a priority request received (53) from one of the transponders, the base system interrupts the schedule and interrogates substantially immediately (56,57,55) the signalling transponder so as to determine its location with minimal latency.