On-line Scheduling of Jobs with Order Arrival Time and Hard Deadline on Two Parallel Identical Machines

On-line scheduling of independent jobs with order arrival time and hard deadlines is an extension of traditional on-line scheduling problems.Based on real booking systems in modern service industry,on-line scheduling of independent jobs with arbitrary order arrival time,job release times and hard deadlines on two parallel identical machines is studied.The upper bound of competitive ratios of on-line algorithms for the two-machine case is analyzed.An on-line greedy algorithm with a competitive ratio of 3 is presented.