3.ANALYSIS OF RESULTSU.K.
3.1.Determination of the anchor point for each gear ratioU.K.
For measurements in gear i and lower, the anchor point consists of the maximum sound level Lwoti, the reported engine speed nwoti and vehicle speed vwoti at BB' of gear ratio i of the acceleration test in Annex II.
=
Lwoti,Annex II
=
nBB,woti,Annex II
=
vBB,woti,Annex II
For measurements in gear i+1 the anchor point consists of the maximum sound level Lwoti+1, the reported engine speed nwoti+1 and vehicle speed vwoti+1 at BB' of gear ratio i+1 of the acceleration test in Annex II.
=
Lwoti+1,Annex II
=
nBB,woti+1,Annex II
=
vBB,woti+1,Annex II
3.2.Slope of the regression line for each gearU.K.
The sound measurements shall be evaluated as a function of engine speed in accordance with point 3.2.1.
3.2.1.Calculation of the slope of the regression line for each gearU.K.
The linear regression line is calculated using the anchor point and the four correlated additional measurements.
where nj = engine speed measured at line BB'
3.2.2.Slope of the regression line for each gearU.K.
The Slopek of a particular gear for the further calculation is the derived result of the calculation in point 3.2.1 rounded to the first decimal place, but not higher than 5 dB/1 000 min–1.
3.3.Calculation of the linear sound level increase expected for each measurementU.K.
The sound level LASEP,kj for measurement point j and gear k shall be calculated using the engine speeds measured for each measurement point, using the slope specified in point 3.2 to the specific anchor point for each gear ratio.
For nBB_k,j ≤ nanchor,k:
LASEP_k,j = Lanchor_k + (Slopek – Y) * (nBB_k,j – nanchor,k)/1 000
For nBB_k,j > nanchor,k:
LASEP_k,j = Lanchor_k + (Slopek + Y) * (nBB_k,j – nanchor,k)/1 000
Where Y = 1
3.4.SamplesU.K.
On request of the approval authority two additional runs within the boundary conditions in accordance with point 2.3 shall be carried out.