Entity Lifetime

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An Entity Lifetime is the Time Interval during which an Entity existed.



References

  • wordnet.princeton.edu/perl/webwn
    • # S: (n) life, lifetime, life-time, lifespan (the period during which something is functional (as between birth and death)) "the battery had a short life"; "he lived a long and happy life"
  • (Wikipedia, 2009) ⇒ http://en.wikipedia.org/wiki/Lifetime_(physics)#Mean_lifetime
    • Mean lifetime: If the decaying quantity is the number of discrete elements of a set, it is possible to compute the average length of time for which an element remains in the set. This is called the mean lifetime (or simply the lifetime) and it can be shown that it relates to the decay rate,
      • \tau = \frac{1}{\lambda}.
    • The mean lifetime (also called the exponential time constant) is thus seen to be a simple "scaling time":
      • N(t) = N_0 e^{-t/\tau}. \,
    • Thus, it is the time needed for the assembly to be reduced by a factor of e.