the post office where the carrier racks and ties the mail before delivering it.
Delivery routes are executed according to a preferred (but not fixed) order.
For each route the average delivery time is known. This information
allows the distribution clerk at the post office to sort mail for each carrier at
the right time. Since the mail sorting process is complex and time con-
suming, it is important to schedule the delivery activities appropriately. The
goal is to minimize delays and to avoid confusion at the post office.
The delivery time plan defines for each carrier the start time of each
delivery route. Since delivery times depend on variable parameters (traffic
conditions, quantity of mail, etc.), each carrier revises the time plan before
starting any new delivery route.
A fitness club organizes training courses for its member athletes. The fitness
room is equipped with a comprehensive range of training machines including
bikes, leg extension machines, rowing machines and weight machines. The
fitness club employs a qualified trainer who designs personalized routines
suited for the club members according to their problems and needs, their
goals (losing weight, strengthening muscles, etc.), and current condition. For
example, three athletes repeat the following routine programmes:
Athlete, A1: 15 min. bike, 15 min. leg extension, 10 min. rowing.
Athlete, A2: 20 min. bike, 15 min. leg extension, 10 min. weight.
Athlete, A3: 20 min. bike, 15 min. leg extension, 10 min. rowing, 10 min.
Exercises are executed according to a preferred (but not fixed) order. The
workout of an athlete consists of a temporal sequence of exercises each one
requiring the exclusive use of a training machine for the entire duration of
his or her exercise. The daily plan defines the usage constraints of each
training machine: the sequence of athletes using a given machine and the
start and end time of each exercise on that machine.
The fitness plan should take into account the individual routines of each
athlete and the duration and sequence of their exercises. The trainer must pay
special attention to minimize the delay between two consecutive exercises
performed by the same athlete in order to prevent his or her muscles from
getting cold. In any case, a minimum delay is recommended for the athlete to
rest (this delay might be accounted for in the duration of the exercise).
During the execution of their training workouts the athletes can revise the
time plan to update the actual duration of each exercise: sometimes athletes
may need additional time to rest or feel able to carry on an exercise (beyond
the time specified by the trainer).
The scheduling tool
The project manager uses the scheduling tool to formulate the time plan for
the project at hand. The tool should provide the user with three fundamental