Improving System Safety Levels at the Defense Logistics Agency

Abstract

In a deterministic inventory system charged with providing spares and repair parts, the right number of spares to carry would be exactly equal to the number of spares the customer would demand during the time it takes to obtain replacements from the relevant resupply process (i.e., procurement, repair, or the order-and-shipping process). Unfortunately, customer demands and resupply process times are not precisely predictable, and thus we need 'safety levels.' The safety level for an item is the extra stock carried above the average number of demands expected over a resupply time for the item. (We occasionally use the term pipeline to refer to the average number of demands over a resupply time - so safety levels represent the extra stock carried above the pipeline. Negative safety levels occur when the number of spares carried is less than the pipeline. ) Safety levels protect us against the statistical fluctuations that occur in most demand-and-resupply processes.

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1993
Accession Number
ADA286037

Entities

People

  • Christopher H. Hanks
  • Tovey C. Bachman

Organizations

  • LMI

Tags

Communities of Interest

  • Materials and Manufacturing Processes
  • Weapons Technologies

DTIC Thesaurus Topics

  • Abstracts
  • Availability
  • Classification
  • Inventory
  • Logistics
  • Pipelines
  • Plastic Explosives
  • Procurement
  • Safety
  • Security
  • Shipping
  • System Safety
  • Weapon Systems

Readers

  • Aviation Safety Risk Assessment.
  • Mathematical Modeling and Probability Theory.
  • Naval Architecture and Marine Engineering.