预先的计划和安排.docx

Is logistics everything?A research on the use(fulness) of advanced planning and scheduling systems.Marjolein van Eck BWI paper, April 2003Is logistics everything?A research on the use(fulness) of advanced planning and scheduling systems.Marjolein van Eck BWI paper, April 2003Vrije Universiteit AmsterdamFaculty of SciencesMathematics and Computer science departments Paper for Business mathematics and Informatics De Boelelaan 1801a1081 HV AmsterdamPrefacePrefaceThis paper is part of the doctoral programme of the study Business mathematics and Informatics (BWI) at the vrije Universiteit Amsterdam. This paper is based on a literature research into advanced planning and scheduling.This research is subtitled: 'Is logistics everything?, which refers to a headline in the NRC Handelsblad on the 29th OfNovember 1997: uLogistiek is alles. (Logistics is everything). An article with the retiring chairman of the EVO, the organisation for logistics and transport.Since a decade the accent in the logistics sector has moved from inside the factories and warehouses to the outside world. The Supply-Chain paradigm has lead to new research areas and technologies in the search for an increased control of the total logistics chain of companies who co-operate to produce and sell products.One of the most remarkable results of the Supply Chain concept is the increase in the use of formal, scientific methods to support the logistical decision-making. With this research I hope to have given a critical and objective view on this new development.I would like to thank my supervisor Ger Koole for his critical view.Marjolein van EckAmsterdam, The Netherlands, April 2(X)3-11 -Executive summarySupply chain management (SCM) is defined as a process for designing, developing, optimising and managing the internal and external components of the supply system, including material supply, the transformation of material and distribution of finished products or services to customers, that is consistent with overall objectives and strategies (Spekman, 1998).The essence of SCM is a strategic weapon to develop a sustainable competitive advantage by reducing investments without sacrificing customer satisfaction (Lee and Billington, 1992). Since each level of the supply chain focuses on a compatible set of objectives, redundant activities and duplicated efforts can be reduced (Spekman, 1998).All companies function as links in chains of entities that produce and distribute products. Many companies have viewed their participation in the supply chain from an independent perspective, and focused on the maximisation of its own profitability. In the traditional view each organisation aims to maximise its own profit, while in the new integrated view each organisation aims to maximise total supply chain success. Therefore a supply chain company in the new view must lose its external boundaries.Four forms of supply chain integration can be distinguished: Physical integration Information integration Management control integration Organisational integrationMaterials requirements planning (MRP) and capacity requirement planning (CRP) systems have been gradually developed towards closed loop systems entitled Manufacturing Resource Planning (MRP II), which integrate both materials and capacity requirements. Latest, Enterprise Resource Planning (ERP) and Advanced Planning and Scheduling (APS) systems have improved the integration of materials and capacity planning by use of constraint-based planning and optimisation. Further many ERP en APS systems make it possible to include supplier and customer in the planning procedure and thereby optimise a whole supply chain on a real-time basis.Instead of an ERP system that focuses on each individual link in the chain, an APS system is a system that suits like an umbrella over the entire chain, thus enabling it to extract real-time information from that chain, with which to calculate a feasible schedule, resulting in a fast, reliable response to the customer.APS is a new revolutionary step in enterprise and inter-enterprise planning. It is revolutionary, due to the technology and because APS utilises planning and scheduling techniques that consider a wide range of constraints to produce an optimised plan: Material availability Machine and labour capacity Customer service level requirements (due dates) Inventory safety stock levels Cost Distribution requirements Sequencing for set-up efficiencyThis paper also discusses the basic functionality of planning and scheduling in Advanced Planning and Scheduling systems (APS). Three basic planning options - concurrent planning (or unconstrained planning), constrained planning and optimisation - are analysed. The planning functionality is radically improved compared to MRP and MRP II.APS is relevant for production-organisations. Also distribution-organisations can benefit from implementing APS fo