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* [[Polynomial-time approximation scheme|Polynomial-time approximation schemes]], which for any ''ε''>0, attain at most (1+ε)OPT. For minimizing the ''maximum'' completion time on two ''uniform'' machines, their algorithm runs in time <math>O(10^{2l} n)</math>, where <math>l</math> is the smallest integer for which <math>\epsilon \geq 2\cdot 10^{-l}</math>. Therefore, the run-time is in <math>O( n / \epsilon^2)</math>, so it is an [[FPTAS]]. For minimizing the ''maximum'' completion time on two ''unrelated'' machines, the run-time is <math>O(10^{l} n^2)</math> = <math>O( n^2 / \epsilon)</math>. They claim that their algorithms can be easily extended for any number of uniform machines, but do not analyze the run-time in this case.
'''Glass, Potts and Shade'''<ref>{{Cite journal|date=1994-07-01|title=Unrelated parallel machine scheduling using local search|url=https://www.sciencedirect.com/science/article/pii/0895717794902054|journal=Mathematical and Computer Modelling|language=en|volume=20|issue=2|pages=41–52|doi=10.1016/0895-7177(94)90205-4|issn=0895-7177}}</ref> compare various [[Local search (optimization)|local search]] techniques for minimizing the makespan on unrelated machines. Using computerized simulations, they find that [[tabu search]] and [[simulated annealing]] perform much better than [[Genetic algorithm|genetic algorithms]].
== Extensions ==
'''Kim, Kim, Jang and Chen'''<ref>{{Cite journal|date=2002-06-01|title=Unrelated parallel machine scheduling with setup times using simulated annealing|url=https://www.sciencedirect.com/science/article/abs/pii/S0736584502000133|journal=Robotics and Computer-Integrated Manufacturing|language=en|volume=18|issue=3-4|pages=223–231|doi=10.1016/S0736-5845(02)00013-3|issn=0736-5845}}</ref> extend the problem by allowing each job to have a setup time, which depends on the job but not on the machine. They present a solution using [[simulated annealing]]. '''Vallada and Ruiz''' present a solution using a [[genetic algorithm]].<ref>{{Cite journal|date=2011-06-16|title=A genetic algorithm for the unrelated parallel machine scheduling problem with sequence dependent setup times|url=https://www.sciencedirect.com/science/article/abs/pii/S0377221711000142|journal=European Journal of Operational Research|language=en|volume=211|issue=3|pages=612–622|doi=10.1016/j.ejor.2011.01.011|issn=0377-2217}}</ref>
== External links ==
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