Abstract: An air sampling system and method are provided to collect air samples from a plurality of air sample inlets. Before or after transmitting an air sample originating from one of the sample inlets, a signal gas is transmitted via the sample line in accordance with one of a plurality of predefined burp patterns, each of which uniquely corresponds to a different one of the sample inlets. The sample line is monitored for the signal gas in accordance with the predefined burp patterns. Based on detection of the signal gas in the sample line in accordance with one of the predefined burp patterns, a related action is taken. The related action can be identifying the sample inlet from which the air sample originated, or further transmitting the air sample via the sample line.

Abstract: An LED illumination system includes control circuitry and first, second and third colored LEDs. The control circuitry sequentially drives the first, second and third colored LEDs in a color cycle frame with relative duty cycles having a known relationship that achieves a color balance. The control circuitry also operates to introduce at least one spoke period in the color cycle frame, during which the first, second and third LEDs are driven in a manner that is controlled to provide brightness adjusting light that matches the color balance achieved by the relative duty cycles of the first, second and third LEDs during sequential driving thereof.

Abstract: The present invention relates to the monitoring of gas concentrations possible in very low ranges (i.e. low ppb and even ppt ranges) and especially use thereof in environmental monitoring, exposure assessment, bomb detection, and health studies. The invention can use a spatial and temporal assessment of gas concentrations that enables the sources of the gas in question to be located and identified which is useful in environmental and health field but can also be applied to other fields an example of which is detecting and locating explosives. This technology can uses small, light weight, and low power components that allow for the monitor to be portable and even worn on a person as a personal monitor. This technology can be used in stationary monitors as well.

Abstract: A field sequential color display system (10) employs a liquid crystal device operating as a variable optical retarder (12) which is positioned in front of the screen (40) of a raster scanned cathode ray tube (38) to develop a high quality multicolored image. The liquid crystal device is divided into upper and lower cell segments (34 and 36) to decrease the time between successive color fields. Each cell segment has a separate electrode structure (30 and 32) and a common electrode structure (22) and is separately commanded by a switching circuit (46) to a predetermined optical retardation state when the electron beam scans the portion of the screen covered by the cell segment. The switching circuit provides signals in a predetermined time sequence to the cell segments to minimize the optical cross talk between them and thereby minimize the spurious transmission of colored light from the display system.

Abstract: A supporting assembly includes a base member having a spherical depression and a supporting platform having a hemispherical projection. The projection is mounted in the depression and a pillar projects through the two members, the pillar being rotatable in the base member and extending through a slot in the hemispherical projection. The top of the pillar is square in section and co-operates with a channel of similar width formed in the hemispherical projection having the same axis as the slot. The arrangement permits a VDU to pivot in one plane only relative to the pillar (so that the edge of the screen remains parallel to a desk top) and to swivel on the base member.