物流管理

Lean Supply Chain鲍梦可A lean supply chain is one in which all participants perform according to lean principles, including level schedule loading using pull-based demand, deployment of continuous improvement activities, maintenance of sufficient (even excess) all participants across the supply chain, and establishing of long-term reciprocal relationships among all participants. Establishing a lean supply chain is important for organization. This is because the supply chain will eventually become noncompetitive if it fails to systematically improve its supply chain performance. This is an important goal because supply chain costs often range between 50%-80% of all money spent by an organization. Another reason to improve operational performance with a high sense of urgency is the fact that customers demand cost reductions, on-time delivery, and higher quality based on the competitive environment. Organizations should also develop internal competencies that competitors cannot easily emulate to remain competitive over time. The 10-step Solution Process can be applied very effectively to improve supply chain performance using Lean Six Sigma and operations research tools and methods.At an operational level, lean supply chain are characterized by rate-based demand and production smoothing through strict take time adherence. Take time is defined as the ratio of time available per day to produce the required schedule, that is, time per unit. As an example, if there are 480 minutes per day and the required manufacturing schedule is 48 units, the take time is 10 minutes per unit. This means the system is configured to produce exactly one unit every 10 minutes. A second characteristic of a lean supply chain is use of a mixed-model production schedule. A mixed-model production schedule minimizes process waste by reducing variations in lead-time and demand through changes to manufacturing schedules. These scheduling changes are enabled through modifications in product and process design. In mixed-model scheduling, the level of design commonality and modularity is significantly increased, insuring that products are scheduled in groups having similar process and design features. A third characteristic of a lean supply chain is use of “demand pull” rather than “demand push” scheduling systems. Demand pull scheduling directly aligns the productive capacity of the supply chain to external customer demand patterns. In these systems, products are built based only on customer orders in real time, that is, up-front forecasting does not drive the schedule except at a high capacity allocation level. Unfortunately, not every organization has been able to fully implement lean supply chain concepts due to infrastructure issue related to IT systems and constraints in product and process designs. In these systems, organizations must rely on the master production scheduling (MPS) and material requirement planning (MRP II) systems to build components and products, however, these situations make control of the system in real time difficult. To improve the local shop-floor control of orders, hybrid Kanban systems have been developed to integrate MPS/MRPII and Kanban systems.Lean supply chains are characterized by the ability to respond dynamically tochanging customer demand as well as efficient asset utilization. These characteristics translate into high profitability and customer service for the organizations making up the lean supply chain. The effectiveness and maturity of a lean supply chain can be measured using the 20 important supply chain metrics. The first 12 key metrics are operational in nature and useful in identification and deployment of Lean Six Sigma projects at a tactical level. The 12 key supply chain metrics should be systematically improved at an operational level by the Lean Six Sigma projects at a tactical level. The 12 key supply chain metrics should be systematically improved at an operational level by the Lean Six Sigma improvement team to drive overall supply chain financial performance and achieve customer service targets. The last 8 metrics are financial in nature and measure the overall financial effectiveness of a Lean supply chain. In particular, they measure the efficiency of asset utilization, including inventory and its impact on profitability. Using these 20 metrics, the degree of “Leanness” of a supply chain can be measured and benchmarked that operational improvements are aligned with business goals and objectives. As an example, in best-in-class originations. The ROA ratio is in the double-digit range for such best-in-class lean supply chains as 3M, Intel, the Home Depot, Johnson and Johnson, Wal-Mart, and Dell. Along this line of though, may studies have shown that the key differentiators for superior supply chain performance include proper metric definition, metric linkage, and sustained operational performance to ensure strategic execution. Lean Six Sigma deployments have enabled many supply chains to improve operational performance as measured by one or more of the 20 important supply chain metrics.Superior supply chain performance is based on specific core competencies inherent within an organization’s supply chain. Core competencies may include improved product development, implementation of Lean Six Sigma practices, elimination of promotional activity to smooth demand, and simplification of product and process designs as well other systems. Some supply chains achieve superior performance by excelling in one more or more of these core competencies. In addition to the competencies already listed, lean supply chains execute strategy will at an operational level. This ensures that sufficient capacity is available for the system to absorb demand variation in real time. These systems are also systematically improved to increase system flexibility. However, lean supply chains do not arbitrarily increase asset levels to achieve system flexibility. This is especially true for inventory investment levels. On the contrary, products and processes are designed, using lean methods, to ensure quick changeovers from one product to another using a variety of methods including, for example, mixed-model production, transfer batches, and system-constraint identification and management.In these planning and control systems, customer demand is forecast at a strategic level, but operations are controlled at a local work-cell level using visual in real time. Supply chain panning and control are enhanced through linkage to external demand using advanced technology. The resultant operational efficiencies are seen in the form of superior return-on-asset (ROA) utilization efficiencies. In addition to ROA, gross margin return-assets (GMROI), calculated by dividing gross margin by average inventory investment, it a good indicator of the efficiency of inventory utilization.精细供应链在精细供应链中，所有参与者都遵从精细原则，包括使用拉式需求的水平卸载计划安排、持续改进活动的部署、维持足够的（甚至过度的）能力去满足外部的需求，严格的计划安排使得整个供应链中的参与者的利润最大化，以及在所有参与者中建立一个长久的互相合作的关系。