Abstract: A method, system and computer program product is disclosed for using a constrained pressure residual (CPR) preconditioner to solve adjoint models. A linear system of fluid flow equations comprising a plurality of variables that represent fluid flow properties in a geological formation of a subterranean reservoir is provided. Matrix (Ã)T, which comprises a transpose of a Jacobian matrix associated with the linear system of fluid flow equations, is constructed. A constrained pressure residual preconditioner MCPRA?1 is constructed responsive to the matrix (Ã)T. Matrix equation (Ã)Ty=d is then solved using the constrained pressure residual preconditioner MCPRA?1.

Abstract: A method, system and computer program product is disclosed for using a constrained pressure residual (CPR) preconditioner to solve adjoint models. A linear system of fluid flow equations comprising a plurality of variables that represent fluid flow properties in a geological formation of a subterranean reservoir is provided. Matrix (Ã)T, which comprises a transpose of a Jacobian matrix associated with the linear system of fluid flow equations, is constructed. A constrained pressure residual preconditioner MCPRA?1 is constructed responsive to the matrix (Ã)T. Matrix equation (Ã)Ty=d is then solved using the constrained pressure residual preconditioner MCPRA?1.

Abstract: A method of distributed control of a wireless mesh network without knowledge of global topology. The method includes: a station joining the network with any current member by propagating the join-request, or two meshes merging using the steps of: one mesh joining the other as a whole and then re-synchronizing its timing. The method further includes: first, each station periodically transmits a beacon; second, in response to a beacon being no longer detected, a station transmitting a bitmap of stations that it can still receive; third, each station responds by adding stations that it can receive with all of the bitmaps received from other members, and retransmitting the updated bitmap; fourth, after time for all stations to respond, all stations base current membership on the bitmap. The method further includes: determining sharable time slots that will not interfere with neighbors or other slot sharers, using and then releasing those slots.

Abstract: A method of controlling and sharing access to a wireless network wherein some stations of the network may be out of range of other stations of the network. The method includes the steps of: first, each station periodically transmits a beacon containing a bit map having a bit location for every station on the network and monitoring the beacons of stations within its range; second, in response to a beacon being no longer detected, each station transmits a bit map containing an indication of only the stations that it can still receive; third, on receiving a bit map with not all stations indicated, each station responds by adding stations that it can receive to the received bit map and transmitting the updated bit map; fourth, each station repeats the third step until the updated bit map indicates that all stations are still in the network or that a station is missing from the network; and finally, if a station is indicated to be missing from the network, each station updates the bit map.