Using CAPE-OPEN standards in the coordinated optimization of plant production scheduling and supply-chain planning
Systematic methods and tools for managing the complexity
Software Architecture, Standards & Interfaces (T4-7)
Keywords: CAPE-OPEN; Supply Chain Management; Decision Support Systems; Planning.
Although the trend towards optimum management of single manufacturing sites has been driven by de integration of aggregate planning and detailed scheduling [1], current Advanced Planning and Scheduling (APS) systems support the decision making process at different levels through different functions, so the consideration of multi-site manufacturing networks and their co-operative supply chain (SC) systems requires a revised perspective and complementary decision making structures.
More specifically, the intrinsic dynamics and complexity of the SC systems, the special characteristics of the different manufacturing networks and the existence of other considerations (e.g. environment) which must be taken into account, are not adequately covered by current approaches.
At the top level, the currently proposed solutions to the Supply Chain Management (SCM) problem imply the use of aggregated models in which part of the information required for the detailed scheduling of the different elements of the SC cannot be considered. Then, the resulting plans must be completed when translated to these elements. The additional decisions to be taken in this process, even if they may be optimal from a local point of view (using different models, different objectives, ….) will lead to different element schedules (plant production schedules, transport schedules, distribution centres occupation schedules, etc.) that from a global SC point of view appear to be suboptimal or even, in the worst case, infeasible.
Additionally, and although this approach is applicable to the different SC layers, from the individual single sites to the global SC optimization, including multi-site (single company) competitive strategic decisions, or the independent management of a similar objective (i.e. benefits, client satisfaction, etc.) for different companies, it does not address the whole multi-enterprise SC allowing individual manufacturing components to dynamically connect and adapt according to market changes and opportunities.
In this work,
i) the natural equivalence between the plant production scheduling problem and the SC planning level is used to extend the CAPE-OPEN APS standard [2] to the SC planning problem,
ii) an equivalent reasoning is used to use also the same approach to solve the rest of elementary planning problems to be faced when addressing the short time SC coordination: transport scheduling, distribution centers occupation scheduling, etc., and
iii) the resulting equivalences are used as linking elements to drive the different local optimums (the solutions resulting from the previous elemental problems) to an integrated result that, although it cannot guarantee global optimality, is essential to the decision maker to get a not only “feasible” but “well balanced” compromise.
The use within the different modules of the basic structures defined in the CAPE-OPEN standards constitutes a “de facto” APS standard extension. Moreover, it allows to integrate different tools (now available or those that can appear in the future) to solve the APS problem, or any of the embedded optimization problems, ensuring compatibility with the CAPE-OPEN standards. In this sense, specific efforts have been devoted to develop a system architecture able to guarantee the maximum reliability in the communication among the different elements of the system.
References.
[1] Erengüç S.S., Simpson N.C., Vackaria A.J. (1999). Integrated production/distribution planning in supply chains: An invited review. European Journal of Operational Research, 115.
[2] CO-LaN consortium (2003): Open Interface Specification: Planning and Scheduling Interface, available at http://www.colan.org/Spec_10/Planning_and_Scheduling_Interface_Specification.pdf
Presented Monday 17, 16:20 to 16:40, in session Software Architecture, Standards & Interfaces (T4-7).
