Technical data

Understanding Your Agilent ChemStation 85

Integration

Peak Recognition

t6 • Peak valley found and upslope counter is greater than or equal to 2 or

• Downslope sigma is greater than twice peak end sigma or

• Baseline reset now or

• Baseline reset next valley and peak valley found

t7 Downslope criterion is no longer met

t8 Downslope criterion is met again

t9 • Peak valley found and upslope counter is greater than or equal to 2 or

• Downslope counter equals zero or

• Downslope sigma is greater than peak end sigma or

• Baseline reset now or

• Baseline reset next valley

t10 Upslope counter is greater than or equal to 2

t11 Upslope counter is less than or equal to 1

Peak Start

In Table 9 on page 85 the expected peak width determines which filter’s slope

and curvature values are compared with the Slope Sensitivity. For example,

when the expected peak width is small, Filter 1 numbers are added to the

up-slope accumulator. If the expected peak width increases, then the numbers

for Filter 2 and, eventually, Filter 3 are used.

When the value of the up-slope accumulator is

¡15, the algorithm recognizes

that a peak may be starting.

Table 9 Incremental Values to Upslope Accumulator

Derivative Filter 1 - 3 Outputs against Slope Sensitivity Filter 1 Filter 2 Filter 3

Slope > Slope Sensitivity +8 +5 +3

Curvature > Slope Sensitivity +0 +2 +1

Slope < (-) Slope Sensitivity -8 -5 -3

Slope > |Slope Sensitivity| -4 -2 -1

Curvature < (-) Slope Sensitivity -0 -2 -1