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Queueing systems: queue variables
  Computes characteristic queue variables from other quantities.
2024.May.16 12:16:40
. s No. of servers.
α, μ, ψ   {A} Arrival rate, service rate, utilization factor  [ψ = α ⁄ ()].
. Lq, Wq   {B} No. of customers and time 'in the queue' (mean values).
  Computes characteristic queue variables from other given quantities in an M/M/s (steady state). A variable is considered input if given as positive, output if null. (Invalid combinations are discarded.)
  Accepted cases (data combinations) are: (1) 2 from group {A}; (2|3) α | μ with Lq or (4) α with Wq; and (5) group {B}.

  Examples [Bronson, 1982]: 23.3 s = 1, α = 24 h−1, μ = 30 h−1L = 4, W = 1 ⁄ 6, p0 = 0.2; 23.14 s = 1, α = 30 h−1, μ−1 = 1.5 min → Lq = 2.25, Wq = 4.5 min, p0 = 0.25; 23.16 s = 1, α = 1 min−1, μ−1 = 45 s → Lq = 2.25, Wq = 2.25 min, W = 3 min, p0 = 0.178; 24.6 s = 3, α = 300 yr−1, μ−1 = 2 d (μ = 182.5 yr−1) → Lq = 0.352, L = 1.996, Wq = 0.001175 yr = 0.43 d, W = 0.006654 yr = 2.429 d, p0 = 0.17754.

References: Plate QUE98303

• [Bronson, 1982]

• Hillier, Frederick, S., Gerald J. Lieberman: 2005, "Introduction to Operations Research", 8.th ed., McGraw-Hill, New York, NY (USA), ISBN 007-123828-X, Ch. 17, "Queueing theory"; 1995, 6.th ed., ISBN 0-07-113989-3, Ch. 16, "The application of queueing theory".

• Waiting line models (=.pdf), Patricia Nemetz-Mills (Eastern Washington Univ.).

• Baker, Samuel L. (Univ. of South Carolina).

• "Dracula" [manual.pdf, (T-)junction], Institute for Transportation Studies, Fac. of Environment, Univ. of Leeds (UK).

 
 
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Created: 2008-03-03 — Last modified: 2008-03-08