Contribution	Distribution	Uncertainty	Std. Deviation	Notes
Oscilloscope's time measurement accuracy	Rectangular	50 ps	=50/ps	From manufacturer's data sheet
Repeatability of simulator	Standard deviation	30.9 ps	30.9 ps	Calculated from a series of tests
System rise time (caused by estimated system rise time)	Rectangular	27 ps	=27/	Estimated measured rise time is corrected for nominal system rise time
Combined uncertainty, u_c(y)	Normal	45.1 ps	45.1 ps	Combining the standard deviation values above
Expanded uncertainty	Normal	93.4 ps=2.07x45.1 ps	N/A	(k=2) if ^uc^(y)/s(q)>3, since ^uc^(y)/s(q)=1.49, must calculate v_eff
Table V. Simulator rise-time uncertainty.

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