Publicly available schedules Certain kinds of schedules reflect information that is generally made available to the public, so that members of the public can plan certain activities around them. These may include things like: • Hours of operation of businesses, tourist attractions, and government offices, which allow consumers of these services to know when they can obtain them. • Transportation schedules, such as
airline timetables,
train schedules,
bus schedules, and various
public transport timetables are published to allow commuters to plan their travels. From the perspective of the organization responsible for making transportation available, schedules must provide for the possibility of
schedule delay, a term in transport modeling which refers to a difference between a desired time of arrival or departure and the actual time. Despite the use of "delay", it can refer to a difference in either the early or late direction. • In
broadcast programming, the minute planning of the content of a radio or television broadcast channel, the result of that activity is the generation of a list of shows to be broadcast at regular times or at specific times, which is then distributed to the public so that the potential audience for the show will know when it will be available to them. •
Concerts and
sporting events are typically scheduled so that fans can plan to buy tickets and attend the events.
Internal schedules An internal schedule is a schedule that is only of importance to the people who must directly abide by it. It has been noted that "groups often begin with a schedule imposed from the outside, but effective groups also develop an internal schedule that sets goals for the completion of micro-tasks". Unlike schedules for public events or publicly available amenities, there is no need to go to the time and effort of publicizing the internal schedule. To the contrary, an internal schedule may be kept confidential as a matter of security or propriety. An example of an internal schedule is a
workplace schedule, which lists the hours that specific employees are expected to be in a workplace, ensure sufficient staffing at all times while in some instances avoiding overstaffing. A work schedule for a business that is open to the public must correspond to the hours of operation of the business, so that employees are available at times when customers are able to use the services of the business. One common method of scheduling employees to ensure the availability of appropriate resources is a
Gantt chart. Another example of an internal schedule is the class schedule of an individual student, indicating what days and times their classes will be held.
Project management scheduling A schedule may also involve the completion of a project with which the public has no interaction public prior to its completion. In
project management, a formal schedule will often be created as an initial step in carrying out a specific project, such as the construction of a building, development of a product, or launch of a program. Establishing a
project management schedule involves listing milestones, activities, and deliverables with intended start and finish dates, of which the scheduling of employees may be an element. A
production process schedule is used for the planning of the production or the operation, while a
resource schedule aids in the logistical planning for sharing resources among several entities. In such cases, a schedule "is obtained by estimating the duration of each task and noting any dependencies amongst those tasks". or
float, and is a core concept for the
critical path method.
In computing Scheduling is important as an internal process in
computer science, wherein a
database transaction schedule is a list of actions from a set of transactions in databases, and
scheduling is the way various processes are assigned in
computer multitasking and multiprocessing operating system design. This kind of scheduling is incorporated into the computer program, and the user may be completely unaware of what tasks are being carried out and when. Scheduling operations and issues in computing may include: • The operation of a
network scheduler or packet scheduler, an arbiter program that manages the movement of certain pieces of information in the computer. •
Open-shop scheduling,
Job Shop Scheduling,
Flow Shop Scheduling Problem, optimization problems in computer science. •
I/O scheduling, the order in which I/O requests are submitted to a block device in operating systems. •
Job scheduler, an enterprise software application in charge of unattended background executions.
In wireless communications Wireless networks should have a flexible service architecture to integrate different types of services on a single
air-interface because
terminals have different service requirements. On top of the flexible service architecture, effective
quality of service (QoS) management schemes are also needed. Therefore, wireless resources need to be shared among all terminals carefully and it is desirable to schedule the usage of wireless resources as efficiently as possible, while maximizing the overall network performance.
In operations research The scheduling of resources, usually subject to constraints, is the subject of several problems that are in the area of research known as
operations research, usually in terms of finding an optimal solution or method for solving. For example, the
nurse scheduling problem is concerned with scheduling a number of employees with typical constraints such as rotation of shifts, limits on overtime, etc. The
travelling salesman problem is concerned with scheduling a series of journeys to minimize time or distance. Some of these problems may be solved efficiently with
linear programming, but many scheduling problems require integer variables. Although efficient algorithms exist to give integer solutions in some situations (see
network flow models), most problems that require integer solutions cannot yet be solved efficiently.
In transportation planning Scheduling is useful in
transportation planning. The important components of transportation improvement proposals include (a) comprehensive evaluations of the scope of work to be completed, (b) reasonably accurate cost estimates for finishing the task, and (c) a feasible project schedule. If any of these factors are not accurately defined, then there is a strong possibility of unexpected difficulties. Poor scoping and/or scheduling may result in serious budget problems, delays and cancellations of transportation improvements, and sometimes even a
domino effect that can negatively impact the entire area's transportation planning.
In education In an educational institution, a timetable must be established that refers students and teachers to classrooms each hour. The challenge of constructing this schedule for larger institutions was addressed by
Gunther Schmidt and Thomas Ströhlein in 1976. They formalized the timetable construction problem, and indicated an iterative process using
logical matrices and
hypergraphs to obtain a solution. ==See also==