Task Force Data Analysis provides input to the Editing Task Force on three items. For vehicles with single gear ratios, remove brackets from text restricting acceleration to no more than 2.0 m/s and continue with adopted text for UN R51.04. Restructure Annex 7 paragraph 4.4. into subparagraphs for clarity. Rework paragraph 3.6.1. to define reference acceleration with v-t-e ratio and specify procedures for determining maximum reference acceleration. Add specification to factor x determination to prevent extreme results and harmonize its representation as either percentage or decimal value.

Overview of rounding principles for calculations in models where results are used for further calculation. Recommends carrying full precision until the end and applying rounding only to final output. Identifies Round Half to Even as standard for modeling and statistics, and Round Half Up as used in UN Regulations. Advises matching output precision to input data uncertainty and not reporting more precision than input data warrants.

Report from the Task Force Data Analysis to the Informal Working Group on Real Driving Sound Emissions and Performance (IWG RD-ASEP) covering several technical matters: clarification on restrictions in UN R51 supplement 11 to avoid high noise levels for single-gear vehicles; restructuring of control range specifications in Annex 7; redefinition of maximum reference acceleration for the sound emission model; discretization of factor x determination with consideration of rounding procedures; clarification of AVAS sound level requirements distinguishing between whole-vehicle and component-level interpretations; and temperature correction application for the sound emission model. Further work topics include indoor testing, EV model simplification, and slope considerations.

Agenda for the 18th meeting of the Task Force Data Analysis, a sub-group to IWG RD-ASEP. The meeting will review and adopt the agenda, discuss the meeting schedule for November and December 2026, continue discussion on necessary amendments to RD-ASEP including LDYN definition, AVAS term alignment with UN R138, temperature correction, indoor testing, simplified EV model with integrated AVAS approach and Supplement 11 amendments, and slopes and parameter table settings. The meeting will review proposals to the TF-Editing and decisions for the next meeting.

Proposal to replace the current logarithmic function with a segmented function that linearizes the curve in the unstable area near the clipping boundary. The new formulation uses a tangent line to the logarithmic curve below the tangency point and clips to a minimum value of 10 dB. Two parameters define the tangency and clipping conditions: clipping value of 10 dB and slope of 5 dB per unit. The detailed formulation provides the mathematical definitions of the logarithmic function, the linearized segment, helper variables, and constraints including tangency and asymptote conditions.