1 Introduction The scheduling of production and transport processes in manufacturing supply chains is currently done separately. Thus, these schedules might lead to a local optimum of an objective pursued by the supply chain. Improvements of the operational supply chain performance might be achieved by an integrated consideration of operations [1]. The integrated production and transport scheduling problem (PTSP) can be formulated as a mixed-integer program (MIP) [3, 6]. The MIP comprises binary optimization variables that represent assignments, e.g. jobs to machines or transport devices, as well as continuous optimization variables like time and costs [2]. Since it belongs to the class of NP-hard problems, exact solutions are limited to small problem instances [7]. In particular, the considered production scheduling is based on a heterogeneous open flow-shop with several consecutive production levels [5]. Each production level n consists of several machines r, which feature a job-class specific processing time and cost. All jobs j have to be processed on one machine at each production level, which is denoted by X_(j,n,r). The processing sequence of assigned jobs is given by Y_(j,j',n,r). The jobs can be stored before the first production level. between production levels and before the assigned tour A_(i,V) departs. Furthermore, jobs can be processed externally (E_j) in a very short time, but causing a comparatively high cost. The transport of jobs from the production facility to their destination is performed by a homogeneous fleet of vehicles v, featuring a limited transport capacity. All considered tours start and terminate at the production facility. If at least one job is assigned to a tour, this tour is conducted (O_v). The tour can depart as soon as the processing of all assigned jobs is finalized. The routing of a tour v between the locations i is given by Z_(v,i,i'). A performed tour involves fixed and variable costs. The variable costs depend on the duration of the tour. In addition, costs for an unpunctual delivery of orders occur. Furthermore, jobs can be shipped directly to their destination in time by a costly third party logistics provider (3PL), denoted by L_j. External processing and 3PL transport ensure the feasibility of the problem.
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