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+--- Thread: I/E Ratio (?) (/Thread-I-E-Ratio)
I/E Ratio (?) - zzzZorro - 02-12-2019
"Inspiratory/Expiatory Ratio Time"
Have thought long and hard to figure out how this whole number of 60. is arrived at when the INSP. Time=1.50 and the EXP. Time=2.56 ?
All express time and the designation [1.50/2.56] is the expressed I/E comparative air exchange ratio (time), is it not?
(I know this is going to be an "AH-SO" revelation, but 'rekon it is time to ask)
Thanks!
[attachment=10191]
RE: I/E Ratio (?) - pholynyk - 02-12-2019
The calculator on my phone tells me that 1.50 over 2.56 is 0.5859...
so round it off and make it a percentage, and you get 60%
It probably should show as 0.59 though...
RE: I/E Ratio (?) - zzzZorro - 02-12-2019
(02-12-2019, 05:30 PM)pholynyk Wrote: The calculator on my phone tells me that 1.50 over 2.56 is 0.5859...
so round it off and make it a percentage, and you get 60%
It probably should show as 0.59 though...
Thank You pholynyk!
It is the same on my calculator. I was trying to find the whole number of six- zero.
RE: I/E Ratio (?) - Sleeprider - 02-12-2019
(02-12-2019, 05:15 PM)zzzZorro Wrote: "Inspiratory/Expiatory Ratio Time"
Have thought long and hard to figure out how this whole number of 60. is arrived at when the INSP. Time=1.50 and the EXP. Time=2.56 ?
All express time and the designation [1.50/2.56] is the expressed I/E comparative air exchange ratio (time), is it not?
(I know this is going to be an "AH-SO" revelation, but 'rekon it is time to ask)
Thanks!
I:E ratio is improperly calculated for the Aircurve 10 by a factor of 100. The ratio is not included in all machines in Sleepyhead. In your case 1.5/2.56 is 0.58 or rounds out to 0.6. The correct way to express this is as a ratio of 1:1.7. Very simply, inspiration and expiration is divided by inspiration time to normalize inspiration to 1.0, and expiration is the second value. It is read as one to one point seven. If we divide 1 by 1.7 we end up back to our ratio of 0.58. So we can correctly express this as either inspiration is 0.58 (58%) of expiration, or 1:1.7.
The math in Sleepyhead is off by a factor of 100 and JediMark and I actually worked through this last May. He made the corrections in code, but the error persists for some machines and some SH versions. The machine actually outputs the I:E ratio to the SD card, but for display purposes, the value returned needs to be divided by 100.
RE: I/E Ratio (?) - zzzZorro - 02-13-2019
(02-12-2019, 06:49 PM)Sleeprider Wrote:(02-12-2019, 05:15 PM)zzzZorro Wrote: "Inspiratory/Expiatory Ratio Time"
Have thought long and hard to figure out how this whole number of 60. is arrived at when the INSP. Time=1.50 and the EXP. Time=2.56 ?
All express time and the designation [1.50/2.56] is the expressed I/E comparative air exchange ratio (time), is it not?
(I know this is going to be an "AH-SO" revelation, but 'rekon it is time to ask)
Thanks!
I:E ratio is improperly calculated for the Aircurve 10 by a factor of 100. The ratio is not included in all machines in Sleepyhead. In your case 1.5/2.56 is 0.58 or rounds out to 0.6. The correct way to express this is as a ratio of 1:1.7. Very simply, inspiration and expiration is divided by inspiration time to normalize inspiration to 1.0, and expiration is the second value. It is read as one to one point seven. If we divide 1 by 1.7 we end up back to our ratio of 0.58. So we can correctly express this as either inspiration is 0.58 (58%) of expiration, or 1:1.7.
The math in Sleepyhead is off by a factor of 100 and JediMark and I actually worked through this last May. He made the corrections in code, but the error persists for some machines and some SH versions. The machine actually outputs the I:E ratio to the SD card, but for display purposes, the value returned needs to be divided by 100.
Thanks so much SR. I keep a running daily tally sheet on specific items to try to filter good/bad results resulting from my tweeking. For a long time I have been ruminating over this figure and figured it was explainable but it was apparently too deep for my shallow mind. So I asked..
Now I know
RE: I/E Ratio (?) - yankees123 - 02-13-2019
Sorry for the silly question but how do you come with the 1.7.
I understand dividing I/e gives you 0.58 but how exactly do you get 1:1.7
Thanks
RE: I/E Ratio (?) - Sleeprider - 02-13-2019
(02-13-2019, 06:05 PM)yankees123 Wrote: Sorry for the silly question but how do you come with the 1.7.
I understand dividing I/e gives you 0.58 but how exactly do you get 1:1.7
Thanks
Divide both inspiration and expiration by inspiration. I/I : E/I = I:E
RE: I/E Ratio (?) - yankees123 - 02-13-2019
Thanks SR, I knew you would explain it so easily!