تحقیق و تفحص در یکپارچه سازی برنامه ریزی تولید کل، کارشناسی ارشد برنامه ریزی تولید و برنامه ریزی تولید کوتاه مدت عملیات فرآیند گروهی از طریق یک مدل داده ای مشترک

A prototype system has been developed by integrating two higher-level hierarchical production planning application programs (aggregate production plan (APP), master production schedule (MPS)) using a common data model integration approach into an existing planning system for short-term scheduling and supervisory batch management which was originally proposed and developed by Richard, J. G., Macchietto, S. & Shah, N. (1999). Integrated decision support in flexible multipurpose plants. Computers & Chemical Engineering, 23, S539–S542. The hierarchical production planning system has been modelled and validated around an industrial scenario concerning multi-site, multipurpose batch process operations making household chemicals from start to transportation to regional warehouses. This preliminary work suggests that the idea of integrating software applications through a common data model, which was originally described by Stanley, G. M. (1994). The emerging trend towards knowledge-based frameworks for computer-integrated manufacturing. Advances in Instrumentation & Control, 49, 1121–1133 and further developed by Rickard, J. G., Macchietto, S. & Shah, N. (1999). Integrated decision support in flexible multipurpose plants. Computers & Chemical Engineering, 23, S539–S542 is feasible. However further research work, improvements and validations are required using varieties of industrial batch process operations and distribution problems to prove its viability.

Traditionally production plans in any manufacturing organisation are developed through three stages, aggre- gate production plan (APP); master production sched- ule (MPS); and short-term production schedule. The APP implements the long-term business policy of an organisation by allocating the type of product to be made on a monthly basis over a horizon of 1 year or more considering only the overall constraints of the business (Chase & Aquilano, 1989). It may be operated over multiple sites. The MPS develops the overall manufacturing plan of a family of products based on anticipated demand of variants and sub-variants of family of products either on a weekly or monthly basis by disaggregating the information generated by the APP. On the other hand, the short-term production sched- ule provides the feasible manufacturing plan of end items based on the information generated by the MPS over a short planning horizon such as 1 week to 1 month. These three stages of production planning are highly inter-linked within the business organisation. For exam- ple MPS provides the vital link between sales, market- ing, distribution, suppliers and the nianufacturing operations of the business. The short-term production schedule provides the link to the plant level in order to facilitate the last minutes changes to the plan as well as to absorb unforeseen events. In order to run a business organisation efficiently as well as to maintain good customer credibility, these three stages of production planning must be able to communicate to each other both at the planning stage as well as execution stages. Currently, most of the world class manufacturing or- ganisations are driving their systems towards this goal by various means. A literature review (Reklaitis, 1992) shows that for some reason or other, these three distinct stages of production planning are not very common within the chemicals processing sectors particularly within the batch processing area. Noticeably, the MPS stage is missed out or not reported. Therefore there is a need for investigating any potential benefits of including it. Further review (Saad, 1990; Pekny, Venkatasubrama- nian & Reklaitis, 1991) also suggests that most of the work relating to long-term production planning and short-term production scheduling of chemical batch process operations are based on a ‘stand alone’ ap- proach, where the two planning systems have been developed independently. There is hardly any evidence in the public domain of systems, which are developed in an integrative manner. Most of the commercial work in this area is confidential in nature and not available in the public domain except as sales brochure published by development houses. Therefore there is a need for investigation particularly on integration aspects of the three planning systems mentioned earlier. These obser- vations prompted the authors to initiate the work de- scribed in this study, particularly to explore the ways these three planning systems can be integrated for effective communications. In this study the authors have proposed a coherent integrated production planning system under a com- mon computing environment and data model taking into consideration various software packages developed by the Centre for Process Systems Engineering (CPSE) in this area. Section 2 contains a brief description of the problem, which is used for this investigative work. Section 3 briefly deals with integration approaches for software application systems. Section 4 gives brief description of the system developed using common data model ap- proach. In Section 5, the system has been validated by solving the problem described in Section 2. Finally, in Section 6, some conclusions are made highlighting the areas where further investigations are required.

It is possible to integrate enterprise-wide hierarchical planning systems through the common data model approach. The system allows to verify the feasibility of the APP and MPS at the operational plant level by presenting the relavant data