A Note on Stochastic Shop Models in Which Jobs have the Same Processing Requirements on Each Machine
研究流水、作业和开放车间中，每项作业在各机器上的加工时间相同但机器速度不同的随机模型，发现当机器速度递增或递减且工作量分布满足似然比排序时，按工作量从小到大或从大到小排序可随机最小化完工时间。
We consider stochastic models for flow shops, job shops and open shops in which the work required by job j is the same at each machine, being a random variable W j . Because machines operate at different speeds, S i , the processing time of job j at machine i is W j /S i ,. It is the main result of this note that in a flow shop where the machine speeds increase (decrease) from the first to last machine and the workload distributions are ordered by a likelihood ratio criterion, then the makespan of the jobs is stochastically minimized by processing the jobs in the order of least to greatest (greatest to least) workload.