## Z94.1 - Analytical Techniques & Operations Research Terminology| A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
UNBOUNDED SOLUTION. Solution with some infinite or unbounded values, and therefore with an infinite optimum for the objective function. [19] UNIQUE OPTIMAL SOLUTION. The optimal solution in a problem which has one and only one optimal solution. [19] UNIT, NONREPAIRED. An item which is not repaired after a failure. UNIT, REPAIRABLE. A unit which can be repaired after a failure. UNIVERSE. The totality of the test of items, units, or measurements, etc., real or conceptual, that is under consideration. UPPER BOUNDED LINEAR PROGRAMMING PROBLEM. A linear programming problem in which all the variables xj are restricted by a corresponding upperbound dj, i.e., xj ≤ dj. [15] USEFUL LIFE. The period from a stated time, during which, under stated conditions, an item has an acceptable failure rate, or until an irreparable failure occurs. [20] UTILITY. A numerical index representing relative preferences assigned among a group of objects, alternatives, prospects, or choices. UTILIZATION PARAMETER. In queuing theory, is the ratio between mean arrival and mean servicing rates. |

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