1. A method for formulating a signal to interference plus noise (SINR) ratio for a plurality of eNodeBs comprising:
receiving a reference symbol receive power (RSRP) value for each of the plurality of eNodeBs;
receiving a reference symbol receive quality (RSRQ) value for each of the plurality of nodes;
exchanging side information between the plurality of eNodeBs, the side information including average transmit power level of data resource elements normalized to average power level of reference signal resource elements for each of the plurality of eNodeBs, wherein the normalization is performed based on a maximum output power of the eNobeB, a resource block size, and a downlink bandwidth;
calculating a SINR ratio based upon the side information, the RSRP value and the RSRQ for each of the plurality of eNodeBs;
determining a target eNodeB based on the calculated SINR ratio for each of the plurality of eNodeBs; and
transmitting, to a mobile device, a handover message indicating the target eNodeB.
2. The method of claim 1 wherein:
the exchanging side information is via an X2 interface application protocol (X2AP).
3. The method of claim 1 wherein:
the exchanging side information via the X2 interface application protocol (X2AP) is via new X2AP messages.
4. The method of claim 1 wherein:
the exchanging side information via the X2 interface application protocol (X2AP) is via modification of existing X2AP messages.
5. An apparatus for formulating a signal to interference plus noise (SINR) ratio for a plurality of eNodeBs comprising:
a memory,
at least one hardware processor, processing instructions stored in the memory, configured to:
receive a reference symbol receive power (RSRP) value for each of the plurality of eNodeBs;
receive a reference symbol receive quality (RSRQ) value for each of the plurality of eNodeBs;
exchange side information between the plurality of eNodeBs, the side information including average transmit power level of data resource elements normalized to average power level of reference signal resource elements for each of the plurality of eNodeBs, wherein the normalization is performed based on a maximum output power of the eNobeB, a resource block size, and a downlink bandwidth;
calculate a SINR ratio based upon the side information, the RSRP value and the RSRQ for each of the plurality of eNodeBs;
determine a target eNodeB based on the calculated SINR ratio for each of the plurality nodes; and
transmit, to a mobile device, a handover message indicating the target eNodeB.
6. The apparatus of claim 5 wherein:
the exchanging side information is via an X2 interface application protocol (X2AP).
7. The apparatus of claim 5 wherein:
the exchanging side information via the X2 interface application protocol (X2AP) is via new X2AP messages.
8. The apparatus of claim 5 wherein:
the exchanging side information via the X2 interface application protocol (X2AP) is via modification of existing X2AP messages.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A valve for selectively closing a flow path through a wellbore in a first direction, the valve comprising:
a body;
a piston surface formable across the flow path in the first direction, the piston surface formed at an end of a shiftable member annularly disposed in the body; and
a flapper member, the flapper member closable to seal the flow path when the shiftable member moves from a first position to a second position due to fluid flow acting on the piston surface.
2. The valve of claim 1, wherein the piston surface includes a plurality of members.
3. The valve of claim 2, wherein each member is annularly disposed within the shiftable member.
4. The valve of claim 2, wherein each member is biased inward toward a centerline of the body.
5. The valve of claim 1, wherein the piston surface is formable across the flow path upon fluid flow in a second direction.
6. The valve of claim 1, wherein the flapper member is movable between an open position and a closed position.
7. The valve of claim 6, wherein the flow tube retains the flapper member in the open position when the flow tube is in the first position.
8. The valve of claim 1, wherein the piston surface is coated with an abrasion resistant material.
9. The valve of claim 1, wherein the shiftable member is biased in the first position by a biasing member.
10. A valve for selectively closing a flow path through a wellbore in a single direction, the valve comprising:
a housing;
a variable piston surface area formable across the flow path in the single direction;
a flow tube axially movable within the housing between a first and a second position due to fluid flow acting on the variable piston surface; and
a flapper for closing the flow path through the valve upon movement of the flow tube to the second position.
11. The valve of claim 10, wherein the variable piston surface includes a plurality of members.
12. The valve of claim 11, wherein each member is movable between a smaller surface area position and a larger surface area position.
13. The valve of claim 12, wherein each member is biased in the larger surface area position.
14. The valve of claim 10, wherein the variable piston surface area is formable across the flow path upon fluid flow in a direction opposite the single direction.
15. A method for selectively closing a flow path through a wellbore in a first direction, the method comprising:
positioning a valve in the wellbore, the valve having a body, a formable piston surface at an end of a shiftable member, and a flapper member;
reducing the flow in the first direction, thereby forming the piston surface;
commencing a flow in a second direction against the piston surface to move the shiftable member away from a position adjacent the flapper member; and
closing the flapper member to seal the flow path through the wellbore.
16. The method of claim 15, wherein the piston surface includes a plurality of members.
17. The method of claim 16, further including moving the plurality of members from an open position to a closed position to form the piston surface.
18. The method of claim 17, further including biasing the plurality of members in the closed position.
19. The method of claim 15, further including reducing the flow in the second direction to move the shiftable member adjacent the flapper, thereby opening the flow path in the first direction.
20. The method of claim 19, further including locking the valve in an open position to maintain the flow path through the wellbore.
21. A method of operating a gas lift well, comprising:
pressurising an annular area with gas, the annular area being formed between a production tubing string and a wellbore;
opening a gas lift valve located in the annulus, the gas lift valve permitting the flow of gas from the annulus to an interior of the production tubing;
closing the gas lift valve;
closing a second valve, the second valve having:
a body;
a piston surface formable across the flow path in the first direction, the piston surface formed at an end of a shiftable member annularly disposed in the body; and
a flapper member, the flapper member closable to seal the flow path when the shiftable member moves from a first position to a second position due to fluid flow acting on the piston surface.
22. The method of claim 21 further including re-opening the second valve.
23. The method of claim 21 further including a plurality of gas lift valves and a plurality of second valves disposed axially along the annulus.
24. The method of claim 21, wherein the gas lift valve is opened due to a predetermined pressure differential between the annulus and the interior of the production tubing.
25. The method of claim 21, wherein the piston surface is formable due to a change in flow between the annulus and the production tubing.
26. An assembly for selectively closing in a single direction a flow path between an annular area and the inside of a production tubing string, wherein the annular area is formed between the production tubing string and a wellbore, the assembly comprising:
a mandrel provided with at least one bore communicating at one end with the outside of the tubing string and at another end with the inside of the tubing string;
a valve for selectively closing a flow path in a single direction, the valve comprising an housing connected to the mandrel, a variable piston surface area formable across the flow path in the single direction, a flow tube axially movable within the housing between a first and a second position due to fluid flow acting on the variable piston surface, and a flapper for closing the flow path through the valve upon movement of the flow tube to the second position; and
a gas lift valve, wherein the gas lift valve communicates with the flow tube through the flapper.
27. The assembly of claim 26, wherein the mandrel is a sidepocket mandrel.