1. A method of estimating leak flow in a gas delivery system, comprising:
determining a total flow value (Qtotv) of the gas delivery system for each of N breaths, wherein Qtotv is one of average total flow Qtot, summation of total flow or integral of total flow;
determining a P\u03b31 value (P\u03b31v) and a P\u03b32 value (P\u03b32v) for each of the N breaths, wherein P is a leak pressure of the gas delivery system, \u03b31 is a first predetermined value, \u03b32 is a second predetermined value, and wherein P\u03b31v and P\u03b32v are one of averages P\u03b31 and P\u03b32 for the breath, summations of P\u03b31 and P\u03b32 for the breath or integrals of P\u03b31 and P\u03b32 for the breath;
setting up a system of N equations, one for each of the N breaths, wherein each of the equations has the form Qtotv=Gorf\xb7P\u03b31v+Gvg\xb7P\u03b32v and uses the determined Qtotv, P\u03b31v and P\u03b32v for the associated breath;
solving the system of N equations for Gorf and Gvg; and
using Gorf and Gvg to calculate instantaneous leak Qleak using Qleak=Gorf\xb7P\u03b31+Gvg\xb7P\u03b32.
2. The method according to claim 1, wherein the determining the total flow value comprises determining an average total flow Qtot of the gas delivery system for each of N breaths, wherein the determining the P\u03b31 value (P\u03b31v) and the P\u03b32 value (P\u03b32v) comprises determining P\u03b31 and P\u03b32 for each of the N breaths, wherein P\u03b31 and P\u03b32 are averages for the breath, and wherein the setting up the system of N equations comprises setting up a system of N equations, one for each of the N breaths, wherein each of the equations has the form Qtot=Gorf\xb7 P\u03b31+Gvg\xb7 P\u03b32 and uses the determined Qtot, P\u03b31 and P\u03b32 for the associated breath.
3. The method according to claim 1, wherein and \u03b31 is between 0.0 and 0.7.
4. The method according to claim 1, wherein and \u03b32 is between 1 and 1.5.
5. The method according to claim 1, wherein \u03b31 is between 0.0 and 0.7 and \u03b32 is between 1 and 1.5.
6. The method according to claim 5, wherein and \u03b31 is 0.6.
7. The method according to claim 6, wherein and \u03b32 is 1.2.
8. The method according to claim 2, wherein the system of N equations is written in matrix form as Q=P\xb7G, where:
Q
=
Q
tot
\ue89e
\ue89e
1
_
Q
tot
\ue89e
\ue89e
n
_
\ue89e
P
=
P
1
\u03b3
\ue89e
\ue89e
1
_
P
1
\u03b3
\ue89e
\ue89e
2
_
P
n
\u03b3
\ue89e
\ue89e
1
_
P
n
\u03b3
\ue89e
\ue89e
2
_
\ue89e
\ue89e
G
=
G
orf
G
vg
.
9. The method according to claim 8, wherein the solving the system of N equations for Gorf and Gvg comprises using the least-mean-squares (LMS) adaptive algorithm to solve the system of N equations for Gorf and Gvg.
10. The method according to claim 9, wherein the solving the system of N equations for Gorf and Gvg comprises performing Gram-Schmidt orthogonalization to P order to produce an orthogonal matrix U and using the orthogonal matrix U in the least-mean-squares (LMS) adaptive algorithm.
11. The method according to claim 8, wherein the solving the system of N equations for Gorf and Gvg comprises using the least squares to solve the system of N equations for Gorf and Gvg.
12. The method according to claim 2, wherein the determining Qtot and P\u03b31 and P\u03b32 for each of the N breaths requires summations of Qtot, P\u03b31 and P\u03b32 to be performed for each of the N breaths, and wherein a starting point for each summation in each breath is during an end of the expiratory phase of a preceding breath immediately prior to the breath a stopping point for each summation in each breath is during an end of the expiratory phase of the breath.
13. The method according to claim 12, wherein for each summation in each breath the Qtot associated with the starting point of the summation and the Qtot associated with the stopping point of the summation are substantially equal to one another.
14. A gas delivery system, comprising:
a pressure generating system adapted to produce a first flow of gas;
a patient circuit operatively coupled to the pressure generating system; and
a controller operatively coupled to the pressure generating system, the controller being programmed to estimate leak flow in the gas delivery system by:
determining a total flow value (Qtotv) of the gas delivery system for each of N breaths, wherein Qtotv is one of average total flow Qtot, summation of total flow or integral of total flow;
determining a P\u03b31 value (P\u03b31v) and a P\u03b32 value (P\u03b32v) for each of the N breaths, wherein P is a leak pressure of the gas delivery system, \u03b31 is a first predetermined value, \u03b32 is a second predetermined value, wherein P\u03b31v and P\u03b32v are one of averages P\u03b31 and P\u03b32 for the breath, summations of P\u03b31 and P\u03b32 for the breath or integrals of P\u03b31 and P\u03b32 for the breath;
setting up a system of N equations, one for each of the N breaths, wherein each of the equations has the form Qtotv=Gorf\xb7P\u03b31v+Gvg\xb7P\u03b32v and uses the determined Qtotv, P\u03b31v and P\u03b32v for the associated breath;
solving the system of N equations for Gorf and Gvg; and
using Gorf and Gvg to calculate instantaneous leak Qleak using Qleak=Gorf\xb7P\u03b31+Gvg\xb7P\u03b32.
15. The gas delivery system according to claim 14, wherein:
the determining the total flow value comprises determining an average total flow Qtot of the gas delivery system for each of N breaths;
the determining the P\u03b31 value (P\u03b31v) and the P\u03b32 value (P\u03b32v) comprises determining P\u03b31 and P\u03b32 for each of the N breaths, wherein P\u03b31 and P\u03b32 are averages for the breath;
the setting up the system of N equations comprises setting up a system of N equations, one for each of the N breaths, wherein each of the equations has the form Qtot=Gorf\xb7 P\u03b31+Gvg\xb7 P\u03b32 and uses the determined Qtot, P\u03b31 and P\u03b32 for the associated breath.
16. The gas delivery system according to claim 14, wherein and \u03b31 is between 0.0 and 0.7.
17. The gas delivery system according to claim 14, wherein and \u03b32 is between 1 and 1.5.
18. The gas delivery system according to claim 14, wherein \u03b31 is between 0.0 and 0.7 and \u03b32 is between 1 and 1.5.
19. The gas delivery according to claim 18, wherein and \u03b31 is 0.6.
20. The gas delivery system according to claim 19, wherein and \u03b32 is 1.2.
21. The gas delivery system according to claim 15, wherein the system of N equations is written in matrix form as Q=P\xb7G, where:
Q
=
Q
tot
\ue89e
\ue89e
1
_
Q
tot
\ue89e
\ue89e
n
_
\ue89e
P
=
P
1
\u03b3
\ue89e
\ue89e
1
_
P
1
\u03b3
\ue89e
\ue89e
2
_
P
n
\u03b3
\ue89e
\ue89e
1
_
P
n
\u03b3
\ue89e
\ue89e
2
_
\ue89e
\ue89e
G
=
G
orf
G
vg
.
22. The gas delivery system according to claim 21, wherein the solving the system of N equations for Gorf and Gvg comprises using the least-mean-squares (LMS) adaptive algorithm to solve the system of N equations for Gorf and Gvg.
23. The gas delivery system according to claim 22, wherein the solving the system of N equations for Gorf and Gvg comprises performing Gram-Schmidt orthogonalization to P order to produce an orthogonal matrix U and using the orthogonal matrix U in the least-mean-squares (LMS) adaptive algorithm.
24. The gas delivery system according to claim 21, wherein the solving the system of N equations for Gorf and Gvg comprises using the least squares to solve the system of N equations for Gorf and Gvg.
25. The gas delivery system according to claim 15, wherein the determining Qtot and P\u03b31 and P\u03b32 for each of the N breaths requires summations of Qtot, P\u03b31 and P\u03b32 to be performed for each of the N breaths, and wherein a starting point for each summation in each breath is during an end of the expiratory phase of a preceding breath immediately prior to the breath a stopping point for each summation in each breath is during an end of the expiratory phase of the breath.
26. The gas delivery system according to claim 25, wherein for each summation in each breath the Qtot associated with the starting point of the summation and the Qtot associated with the stopping point of the summation are substantially equal to one another.
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 one-piece, screw-receiving abutment for use with an endosseous dental implant, comprising, at its proximal end, an unthreaded cylindrical portion, and proximal to said unthreaded cylindrical portion, a frusto-conical portion with an unthreaded external surface and a retentive, circumferential groove for engaging a transfer component or a comfort cap, and a distal, partly-threaded shank of a size and shape appropriate to engage internal threads of an implant, said shank extending distally from beneath said unthreaded cylindrical portion, and said abutment including an internal passage extending distally into an opening at the proximal end of said implant, said internal passage including multi-sided, wrench-engaging surfaces and a threaded region.