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This research addresses the single machine scheduling problems with controllable processing times. In this area, it is often assumed that the possible processing time of a job can be continuously controlled, i.e. it can be any number in a given interval. When the processing times of jobs are controllable, selected processing times affect both the manufacturing cost and the scheduling performance. In this study, our objective is determining a set of compression/expansion of processing times as well as a sequence of jobs simultaneously, so that total tardiness and earliness on a single machine are minimized. In this way, we first propose a mathematical model for the considered problem and then a net benefit compression-net benefit expansion (NBC-NBE) heuristic is presented for obtaining a set of amounts of compression and expansion of jobs processing times in a given sequence. Also, a simulated annealing approach is used to solve medium to large size problems as an effective local search method. The addressed problem is NP-hard since the single machine total tardiness problem (SMTTP) is already NP-hard. The computational results show that our proposed heuristic is an efficient solution method for such Just-In-Time (JIT) problem.