Abstract: A damper for controlling fluid flow may include a main body, a stator that includes a plurality of stator blades, and a rotor moveably connected to the stator and including a plurality of rotor blades. The damper may also include a rotation mechanism mounted to the main body to move the rotor between an opened position and a closed position. The shape of each of the plurality of stator blades and rotor blades may combine to form a shape such that the velocity of the fluid is increased thereby reducing or eliminating back pressure when the rotor is in the opened position.

Abstract: A damper for controlling fluid flow includes a main body, a stator and a rotor. The stator may be carried by the main body and include at least one blade having a predetermined shape. The rotor may be moveably connected to the stator and carried by the main body. The rotor may include at least one blade having a predetermined shape and may be moveable between an opened position and a closed position. The predetermined shape of the at least one stator blade and the at least one rotor blade may form a converging-diverging nozzle, and the stator and the rotor may be carried by the main body so that fluid flows through the main body substantially perpendicular thereto. The opened position may be defined as the at least one stator blade being aligned with the at least one rotor blade, and the closed position may be defined as the at least one stator blade being offset from the at least one rotor blade.

Abstract: A damper for controlling fluid flow includes a main body, a stator and a rotor. The stator may be carried by the main body and include at least one blade having a predetermined shape. The rotor may be moveably connected to the stator and carried by the main body. The rotor may include at least one blade having a predetermined shape and may be moveable between an opened position and a closed position. The predetermined shape of the at least one stator blade and the at least one rotor blade may form a converging-diverging nozzle, and the stator and the rotor may be carried by the main body so that fluid flows through the main body substantially perpendicular thereto. The opened position may be defined as the at least one stator blade being aligned with the at least one rotor blade, and the closed position may be defined as the at least one stator blade being offset from the at least one rotor blade.

Abstract: Telecommunication carriers that provide collect and bill-to-third-party calls face considerable revenue losses due to unbillable, uncollectible, and fraudulent calls. This real-time call validation system reduces the number of unbillable calls by determining when the dialed number has been ported, the originating carrier has no billing relationship with the terminating carrier, or the dialed number belongs to a customer of a switchless reseller, all events that in today's environment would result in an unbillable call. This system also decreases subscriber fraud by identifying in real-time a dialed number's listed name and address and determining whether there are other numbers associated with said name and address and, if so, whether they are associated with a history of fraud, bad debt, or unbillability. Finally, this system provides a real-time method for applying industry-standard credit assessment tools to the management of collect and bill-to-third-party accounts.

Abstract: Call forwarding can be used to commit fraud or to evade security controls in inmate calling systems. Information from the Common Channel Signaling (CCS) network can be used to detect when a dialed number has been call forwarded and furthermore prevent the call forwarding event from occurring. It is possible to determine whether a dialed number has been call forwarded by setting up a call to that number with the Redirection Counter in the Initial Address Message set to the maximum value allowed in the signaling system being utilized (e.g., CCS7). If the terminating switch fails to set up the call even though the trunk is available, the assumption is made that the call is call forwarded. A second attempt is then made to set up the call a second time setting the Redirection Counter in the Initial Address Message to zero. If the terminating switch returns an Answer Complete Message indicating that the call has been successfully set up, then it has been demonstrated that the dialed number is call forwarded.