Presents a two-echelon inventory model for Air Force recoverable items in periods of dynamic change in the demand process, such as during initial provisioning or wartime. Affirms that steady-state models should be used only or mostly when flying activity is relatively stable. The report also investigates the validity of a longstanding assumption in the mathematics of inventory systems: that depot delay in the resupply of serviceable parts to a base is independent of the number of units in base resupply. Comparing the outputs of two dynamic models, one embodying the assumption and the other entailing meticulous computations, the author concludes that the assumption, although untrue, has a negligible effect on performance measurement and stockage requirements, and that logisticians therefore may freely embody it in their models because of its mathematical convenience.
Muckstadt, J. A., Comparative Adequacy of Steady-State Versus Dynamic Models for Calculating Stockage Requirements. Santa Monica, CA: RAND Corporation, 1980. https://www.rand.org/pubs/reports/R2636.html.
Muckstadt, J. A., Comparative Adequacy of Steady-State Versus Dynamic Models for Calculating Stockage Requirements, Santa Monica, Calif.: RAND Corporation, R-2636-AF, 1980. As of October 07, 2021: https://www.rand.org/pubs/reports/R2636.html