19-1: Define detailed scheduling.

Scheduling involves allocating specific resources such as labor, equipment, and facilities to produce a product or deliver a service. As scheduling is constrained by the higher level planning decisions, it is typically narrow in scope and has short-term time horizons. Scheduling requires operations managers to balance several conflicting goals so that resources are used effectively, productivity is increased, and overall costs are minimized through reductions in customer waiting time, work-in-process inventories, and processing times.

19-2: Demonstrate the main types of scheduling and show when each type should be employed.

Manufacturers use different methods for scheduling, depending on their specific types of operations. Line process scheduling is used for high-volume production processes that typically produce standardized products and require identical or similar operations. Because of the highly repetitive nature of production in these systems, many scheduling decisions are predetermined when these production systems are designed. In intermittent process scheduling, a firm produces a variety of products in relatively low volumes. Products are made to order, and each order has its unique material and processing requirements, processing sequence, and processing time. Because of these varying product requirements and because the firm’s schedules cannot be established before the receipt of actual job orders, job-shop scheduling is considerably more complex than line process scheduling is. The primary problem in intermittent process scheduling is how to manage the queues of work-in-process inventories that build up at each work center as jobs wait for these work centers to become available. The challenges of line process scheduling and intermittent process scheduling require the application of various scheduling tools for the most efficient application of resources.

19-3: Explain why scheduling is complex.

Scheduling is complex because setup and processing times and job priorities vary frequently, and machines setup times depend on the order of job processing. Furthermore, in job-shop scheduling, schedule changes and disruptions occur frequently as a result of the high variety and low volume of jobs that require processing through shared resources. Given the innumerable alternatives and job permutations, it is impossible to analyze all of them in real time to arrive at an optimal schedule. Fortunately, the availability of many computer programs that provide interactive computing and graphic output, the ability to monitor events, and the collection of real-time information makes real-time scheduling possible.

19-4: Describe the scheduling methods used in service organizations.

Scheduling for services poses different challenges than does scheduling for processes in manufacturing firms, and it requires different techniques. For example, appointment systems and reservation systems are all methods for scheduling services. Finally, workforce scheduling represents a significant challenge in applying a supply (or a capacity) side approach to the scheduling problem.

19-5: Describe supply chain scheduling.

Supply chain scheduling depends on the scheduling decisions made by upstream and downstream partners in the supply chain, making it highly complex and subject to both expected and unexpected constraints from supply chain partners. Supply chain scheduling is the process of coordinating scheduling decisions made by any member of the supply chain with the decisions of the other supply chain partners. Such coordination achieved through information sharing and cooperation among supply chain members can improve overall supply chain performance.

19-6: Explain how companies can make scheduling decisions to promote sustainability.

A component of scheduling that is rarely considered is the manner in which sustainability plays a part in the scheduling decision; that is, how can an organization develop schedules that are efficient but also maximize sustainability goals? Manufacturing companies, for example, can reduce energy consumption by using state-of-the-art production equipment and by limiting peak electric power consumption to specific hours of the day or seasons of the year. Similarly, transportation companies can reduce the emission of greenhouse gases and other air pollutants by introducing alternative fuel vehicles such as hybrids or electric transports. To promote sustainability, service organizations such as hospitals and restaurants should develop employee schedules that ensure that employees are not overworked and that they are able to balance their work hours and personal life.

› Chapter Outline