Supply chain networks

Such a supply chain network easily adds up to tens of thousands of nodes and edges with which the product relations are described, whereby a node can represent raw material, an intermediary product or a final product. An edge represents the relationship between two products. As there are usually predecessor/successor relations, the relation network can be interpreted as a directed graph. The material flow is modelled in form of an edge, material factors and offset times are stored as attributes [3,10, 23, 25, 33]. 

The network aspect in supply chains is illustrated by Shapiro where supply chain networks are composed by notes connected by transportation networks (Shapiro 2001, p. 6). Compared to Corsten, Shapiro extends the supply chain including many-to-many-relations between vendors, plants, distribution centers and markets. 

Chopra and Meindl support the aspect of many-to-many relations and a supply chain network. Additionally, they add the aspect of direct relations between partners in the supply chain across several supply chain steps. The primary purpose of the supply chain is to satisfy customer needs, in the process generating profit for itself (Chopra/Meindl 2004, p. 5). 

Concluding, the supply chain and supply chain network concept extends Porter s value chain concept towards cross-company networks in order to improve efficiency and delivery service, minimize costs and inventories... 

The value chain network combines illustrations of the different supply chain network (see fig. 7). 

Several simulation-based optimization models in the context of supply chain management can be found e.g. in the area of supply chain network optimization (Preusser et al. 2005) or to simulate rescheduling of production facing demand uncertainty or unplanned shut-downs (Tang/Grubbstrom 2002 Neuhaus/Giinther 2006). A basic approach of simulation-based optimization is presented by Preusser et al. 2005, p. 98 illustrated in fig. 24. 

In literature simulation and simulation-based optimization is focused on supply chain management areas such as production (Smith 2003 Wullink et al. 2004), inventory (Siprelle et al. 2003), transportation or integrated supply chain networks (Preusser et al. 2005). 

Chen C, Lee W (2004) Multi-objective optimization of multi-echelon supply chain networks with uncertain product demands and prices. Computers Chemical Engineering 28 (6-7) 1131-1144... 

Chen C, Wang B, Lee W (2003) Multiobjective Optimization for a Multienterprise Supply Chain Network. Industrial Engineering Chemistry Research 42 1879-1889... 

Lakhal S, Martel A, Kettani O, Oral M (2001) On the optimizaton of supply chain networking decisions. European Journal of Operational Research 2 259-270 Large R (2000) Strategisches Beschalfungsmanagement. Gabler, Wiesbaden Laudicina PA (2004) World out of Balance. McGraw-Hill, Boston et al. 

Preusser M, Almeder C, Hartl RF, Klug M (2005) LP Modeling and Simulation of Supply Chain Networks, In Gunther HO, Mattfeld DC, Suhl L (eds) Supply Chain Management und Logistik Optimierung, Simulation, Decision Support. Physica, Heidelberg, pp 95-114... 

Tsiakis, P., Shah, N., and Pantelides, C.C. (2001) Design of multiechelon supply chain networks under demand uncertainty. 

Tsiakis P, Shah N, Pantelides CC (2001) Design of Multi-echelon Supply Chain Networks under Demand Uncertainty. Industrial Engineering Chemistry Research 40 3585-3604... 

C.L. Chen, B.W. Wang, W.C. Lee, Multi-objective Optimization for Multi-enterprise Supply Chain Networks, Ind. Eng. Chem. Res. 42 (2003) 1879-1889. 

A. Nagurney, J. Dong, and D. Zhang, A Supply Chain Network Equilibrium Model, Transportation Research Part E, 38, 281-303 (2002). 

L. Benyoucef, H. Ding, C. Hans, and X. Xie, On a New Tool for Supply Chain Network Optimization and Simulation, Proceedings of the 2004 Winter Simulation Conference, 2004. 

Supply chain networks Simultaneous maximization of (1) participants expected profits, (2) average safe inventory level (for plants, distribution centers and retailers), (3) average customer service levels (for retailers), (4) robustness of selected objectives to demand uncertainties and fair profit distribution. A two-phase fuzzy decisionmaking method Chen and Lee (2004) extended the smdy of Chen et al. (2003) by including uncertainty in product demands and prices. Cheu et al. (2003b) Cheu and Lee (2004)... 

Hugo, A. and Pistikopoulos, E. N. (2005). Environmentally conscious long-range planning and design of supply chain networks, J. Clean. Prod, 13, pp. 1471-1491. 

Step 3—Select Route or Movement for Evaluation Depending upon the complexity of the supply chain network, it may first be desirable to divide the transportation activities into more manageable gronps. These may include specific chemicals or chemical classes, modes of transportation, movements, regions, in-transit storage (yard or warehonse), etc. 

Supply chain network Warehouses will not be viewed as independent operations but as an element of the overall, well-planned supply chain. 

Depending on the type of analysis, a DSS may require collecting information from various parts of the company. For example, supply chain network design requires both static and dynamic information from different parts of the company. The static data include plant production rates, locations of the plants, warehouses, and customers as well as warehousing costs and transportation costs, and the dynamic data involve forecasts, orders, and current deliveries. This type of information will not usually be found in one database or one department in a company. 

Uncertainty breeds inventory. Managers involved in transportation often have to make planning decisions, like routing, that directly affect the movement of raw materials or finished goods. These decisions often affect other components in the supply chain network, in which case the transportation management team cannot afford to make an incorrect decision. Consequently, any mistakes not only jeopardize other elements within the system but also lead to customer dissatisfaction created by the delay in the delivery times (Quirm 1998). 

Typical TRPM systems perform some of the same operational tasks as transportation administration and management systems but have the ability to plan and execute enterprise-wide pians rather than single business unit plans. Such systems, therefore, must consider inbound, outbound, and replenishment demands throughout a global supply chain network. 

Figure 2 Supply Chain Network Structure. (From D. M. Lambert, M. C. Cooper, and J. D. Pagh, Supply Chain Management Implementation Issues and Research Opportunities, IntemationalJour-nal of Logistics Management, Vol. 9, No. 2, 1998, pp. 1-19. Reprinted with permission)...

One key element of managing the supply chain is to have an explicit knowledge and understanding of how the supply chain network stmcture is configured. The three primary structural aspects of a... 

Supply chains look different from each company s perspective because management of each company sees its firm as the focal company and views membership and network stmcture differently. Thus, the perceived supply chain network stmcture is arbitrary. However, because each firm is a member of the other s supply chain, it is important for management of each firm to understand its interrelated roles and perspectives. This is because the integration and management of business processes across company boundaries wfil be successful only if it makes sense from each company s perspective (Cooper et al. 1997b). 

The mapping of the supply chain for a focal company is an important step in understanding the interrelationships that impact the success of the business. Several important points need to be kept in mind before proceeding with the mapping of the supply chain network ... 

---