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This paper describes the benefits of integrating optimization formulations within simulation models. Two different case studies in mining are presented, both requiring a blending optimization. The primary problem at hand is to model a complex supply chain involving blending of multiple inputs to produce a number of potential products for customers. The first approach involves solving an optimization model to produce a long term plan, then simulating this plan over time without the ability to change the plan as time progresses. The second approach involves a more integrated system where multiple instances of an optimization model are run throughout the simulation using updated inputs. A description of the problem is supplied, providing the need for both optimization and simulation, and then the two case studies are compared to show the benefits of integrating the optimization within the simulation model. 1898 978-1-4244-9865-9/10/$26.00 ©2010 IEEE

Early-type galaxies (ETGs) possess total density profiles close to isothermal, which can lead to non-Gaussian line-of-sight velocity dispersion (LOSVD) under anisotropic stellar orbits. However, recent observations of local ETGs in the MASSIVE Survey reveal outer kinematic structures at 1.5Reff (effective radius) that are inconsistent with fixed isothermal density profiles; the authors proposed varying density profiles as an explanation. We aim to verify this conjecture and understand the influence of stellar assembly on these kinematic features through mock ETGs in IllustrisTNG. We create mock Integral-Field-Unit observations to extract projected stellar kinematic features for 207 ETGs with stellar mass M* ≥ 1011 M⊙ in TNG100-1. The mock observations reproduce the key outer (1.5Reff) kinematic structures in the MASSIVE ETGs, including the puzzling positive correlation between velocity dispersion profile outer slope γouter and the kurtosis h4’s gradient. We find that h4 is uncorrelated with stellar orbital anisotropy beyond Reff; instead we find that the variations in γouter and outer h4 (a good proxy for h4 gradient) are both driven by variations of the density profile at the outskirts across different ETGs. These findings corroborate the proposed conjecture and rule out velocity anisotropy as the origin of non-Gaussian outer kinematic structure in ETGs. We also find that the outer kurtosis and anisotropy correlate with different stellar assembly components, with the former related to minor mergers or flyby interactions while the latter is mainly driven by major mergers, suggesting distinct stellar assembly origins that decorrelates the two quantities.

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