Describing Processes, Blackboard Flashcards
What is a process?
A simple way of getting things done.
To decide where a process begins or ends…
We must first determine the reason for looking at the process.
What does mapping a process do?
Mapping a process helps to understand it and to identify potential problems in the product or service delivery process.
Operations steps are denoted by…
A circle or square.
Queues or inventories are denoted by…
An inverted triangle.
What is lead time?
When the customer can expect delivery. Also referred to as response time.
What are the three stages of inventory?
Raw materials, work in progress, and finished goods.
What is capacity?
Capacity is the ability to perform work and is typically measured as the number of customers that can be served or the number of products/tasks that can be completed in a certain time period.
If a bank teller can serve 12 customers an hour and there are 5 tellers on duty, what is the total teller capacity per hour?
60 customers per hour.
Many operations do not operate at their full capacity, because…
Demand is less than capacity.
Since assets often work at less than capacity, accounting systems often…
Create a measure to determine how much of their capacity is actually used. This is an asset’s utilization level.
Utilization is…
Work performed/Work that could have been performed
Time worked/Time available for work
If a process is seen as a series of individual operations all dedicated to making a particular product…
Then the individual operation with the least amount of capacity would set the overall capacity (or maximum output rate) for the process as a whole.
What is the bottleneck?
The slowest step. Sets the capacity for everything even if other steps have higher capacity.
Conceptually, in manufacturing systems the planning process should intervene to ensure that…
Flows are balanced - not capacities.
What is the time between batches?
Set-up time. This covers clearing the finished job from the system and setting up for the new one.
What is static capacity?
Example: 300 seats in a cinema is the static capacity.
What is flow capacity?
Example: Six movies shown in one day, so flow capacity of the 300 seat cinema is 1,800 people per day.
Lead times are defined as…
The time from the receipt of a customer order to the delivery of that order.
An example of throughput times?
A restaurant - throughput time is started when the customer joins the line and lasts until the customer has eaten the meal.
How are throughput times most easily calculated?
By assessing the amount of work in process and then using the output rate (or the system cycle time) to arrive at the approximate time.
Throughput time equation?
WIP/output rate
WIP x System cycle time
WIP equation?
Physical inventory + virtual inventory
