Abstract: A positive air pressure system resists debris accumulation on an active surface and comprises a frustum-shaped shroud with a baffle plate therein dividing the shroud into baffles, including a positive pressure chamber and a passive back pressure chamber interconnected through an orifice in the baffle plate. An inlet opening is formed in the shroud and in fluid communication with the proximal baffle and a positive pressure air source and to receive air through the inlet opening from the positive pressure air source and create a high-pressure region, greater than a pressure region in the passive back pressure chamber, and in front of the active surface and to expel air out of the positive pressure chamber and into the passive back pressure chamber through the orifice in the baffle plate.

Abstract: A positive air pressure system resists debris accumulation on an active surface and comprises a frustum-shaped shroud with a baffle plate therein dividing the shroud into baffles, including a positive pressure chamber and a passive back pressure chamber interconnected through an orifice in the baffle plate. An inlet opening is formed in the shroud and in fluid communication with the proximal baffle and a positive pressure air source and to receive air through the inlet opening from the positive pressure air source and create a high-pressure region, greater than a pressure region in the passive back pressure chamber, and in front of the active surface and to expel air out of the positive pressure chamber and into the passive back pressure chamber through the orifice in the baffle plate.

Abstract: An enforcement transponder system includes an enforcement reader in communication with an enforcement transponder. The transponders are written to identify when and where toll has been collected from a user of a toll road. In one embodiment, the system includes one or more roadside toll collection systems. This allows enforcement/verification of toll collection from SOV traffic on HOT lanes.

Abstract: A mobile enforcement reader (MER) includes an antenna, a reader coupled to receive signals from the antenna and a control/display unit (CDU) coupled to the reader. The CDU selects a receive direction and processes signals provided thereto from the reader. When the MER and a transponder are in proximity, the MER interrogates the transponder and receives information related to toll payment. The MER allows enforcement officials to monitor payment by single occupancy vehicle (SOV) traffic for use of high occupancy traffic (HOT) lanes.

Abstract: An enforcement transponder system includes an enforcement reader in communication with an enforcement transponder. The transponders are written to identify when and where toll has been collected from a user of a toll road. In one embodiment, the system includes one or more roadside toll collection systems. This allows enforcement/verification of toll collection from SOV traffic on HOT lanes.

Abstract: A mobile enforcement reader (MER) includes an antenna, a reader coupled to receive signals from the antenna and a control/display unit (CDU) coupled to the reader. The CDU selects a receive direction and processes signals provided thereto from the reader. When the MER and a transponder are in proximity, the MER interrogates the transponder and receives information related to toll payment. The MER allows enforcement officials to monitor payment by single occupancy vehicle (SOV) traffic for use of high occupancy traffic (HOT) lanes.