Supply production scheduling

Requirements for labelling of containers for supply may differ from those for conveyance. Key features of a supply label are to identify the substance (the chemical name in most cases) and any hazards and safety precuations. In Europe the classification, packaging and labelling of dangerous substances is covered by Directive 67/548/EEC as amended. This requires labels to identify appropriate risk and safety phrases (Tables 12.2 and 12.3) depending upon product properties. A substance is considered dangerous if in Part lA of an approved list or if it exhibits hazardous properties as defined in Schedule 1 for supply, or Schedule 2 for conveyance as shown in Tables 12.4 and 12.5. Substances not tested should be labelled Caution — substance not yet fully tested . Criteria for risk phrases are provided, e.g. as in Table 12.6 for toxic compounds. 

Confirmation/revision of the offer for industrial-scale supplies Conclusion of supply contract Plant adaptation Production scheduling, operator instruction CD <3 CD n >-5 -5... 

Supporting IT systems Finally, the accuracy and speed of an integrated process is heavily influenced by the availability of IT systems, which provide a common database, automated functions like Materials Requirements Planning (MRP), and opportunities for simulation and optimization (for instance, real time finite capacity production scheduling, or on-line customer order confirmation based on existing overall supply chain inventory or capacity). 

To ease production schedules, key intermediates may be outsourced from vendors. Reliable delivery of outsourced materials is crucial to making key production goals. By requesting that materials arrive some weeks before they are needed, the company can build a hedge into a campaign schedule. As the success of and demand for the product rises, a company may qualify several suppliers to ensure continued supply of key intermediates. 

For cellular high-throughput screens, a cell production schedule needs to provide a continuous supply of cells for the duration of the screen. It is critical to ensure that cells that have gone through multiple and differing numbers of passages to maintain their pharmacological responsiveness profile. 

Quality control of material, to be effective, must be close to the point of manufacture. Hence the emphasis on the supplier controlling its process while the material is being produced, backed-up by separate batch testing. The delivery that reaches the customer and is then found to be defective has far-reaching implications on product scheduling, market supply and, eventually, customer confidence. 

Production-inventory systems are one of the most established subjects in industrial engineering. The focus is on studying inventory dynamics, with inventory viewed as a buffer between supply (production/replenishment) and customer demand. Hence the emphasis is really more on inventory than on production, the latter being the primary focus of other IE subjects, such as scheduling and production planning. 

The manufacturing process in make-to-stock firms traditionally produced and supplied product to the distribution channel based on historical forecasts. Products were pushed through the plant to meet a schedule. Often the wrong mix of products was produced, resulting in unneeded inventories, excessive inventory carrying costs, mark-downs, and transshipments of product. 

As inventory is maintained at various warehouses as well as the manufacturer, a large amount of material can be sitting in inventory in the supply chain. As replacement orders pass down the supply chain, the orders are pulled from the inventory that is available. If we look at a simple example of a retail store to a warehouse to the manufacturer, the order quantities will be smaller from the retail store to the warehouse, which will try to cover the orders quickly with inventory. When the inventory reaches a low level at the warehouse, a larger replacement order is placed with the manufacturer. The retail store may order 10 items per week, and the warehouse has an inventory of 100 items. For nine weeks there are no orders placed to the manufacturer and in the tenth week an order for 100 items is placed. If the manufacturer had 100 items in inventory they would have been held for more than nine weeks before they could be shipped to the customer. This adds storage costs to the manufacturer and can disrupt the production schedule when the large order arrives. This reaction in the supply chain is called the bullwhip effect. ... 

Eisenstein and Iyer [33] provide a description of a project to improve supply availability in the Chicago Public School System. The supply chain consisted of a warehouse that supplied products to 600 public schools. The products included engineering and educational supplies. Engineering supplies, also called Class A, included toilet paper, paper towels, rock salt, and so on, and accounted for about 50% of dollar value of the warehouse shipments but 1% of the items and 70% of the shipment volume. Educational supplies, also called Class B, accounted for 99% of the items, 50% of the dollar volume, and 30% of the physical volume. In the original system, all items shared a common truck capacity to minimize waste shipment space. Each school had a scheduled delivery once every two weeks. 

It is critical that firms be able to plan and schedule production in their own firms accurately for supply chain integration to work. The master production schedule is the outcome of all of the planning. It is the contract between one firm and its marketing department and hence the remainder of the supply chain. If one member of the supply chain cannot create a valid master production scheule and adhere to the schedule, then there is a large amount of variance within the chain and all remaining members of the supply chain must include a large amount of either spare capacity or lead time to ensure that they deliver when they agreed to. 

According to APICS, the input is a five- to ten-year business plan and the output is a 12- to 18-month master production schedule. The product of the S OP process produces tactical plans to balance supply and demand. ... 

PLAN processes have an operational focus, such as generating production schedules. They also cover periodic replanning project efforts, such as evaluating assets and supply chain partners. These are neglected in many companies, with replanning done only in response to a crisis of some kind. The effectiveness of PLAN processes is measured by supply chain response time and flexibility to react to supply and demand changes. 

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