ABSTRACT
This chapter presents an illustrative application of the Second-order adjoint sensitivity analysis methodology (2nd-ASAM) to a paradigm particle diffusion problem that admits an exact solution. In this problem, all of the first-order relative response sensitivities to the model parameters will be shown to have significantly large values, of order unity. The parameters in this problem are determined from experiments afflicted by uncertainties; in particular, the uncertainties for the basic neutron cross sections are provided in centrally deposited "covariance files." One of the main uses of sensitivities is for ranking the relative importance of parameter variations in influencing variations in responses. The chapter illustrates the use and influence of sensitivities for performing "predictive modeling," combines computational and experimental information to obtain optimally predicted "best-estimate" nominal values for the model responses and parameters while reducing their respective predicted uncertainties.
