Interrupts

Interrupts (or failures/stops) help the user model real-world behavior as closely as possible in a Discrete Rate Simulation. Interrupts are directly related to reliability, which is the probability that a system will perform its intended function for a specified period of time. For example, a reliability of 0.8 at 100 hours indicates that after 100 hours, there is an 80% chance that the system is still functioning.

Interrupts can be imported or added directly in the Constraints pane.

Each Interrupt has the following parameters:

• Name

• Interrupt Type

• Uptime Distribution

• Uptime Parameter 1

• Uptime Parameter 2

• Downtime Distribution

• Downtime Parameter 1

• Downtime Parameter 2

Interrupts are often classified using a failure rate graph often referred to as a 'bathtub curve'. This graph is used in reliability engineering and deterioration modeling to characterize the times between failures. The 'bathtub' refers to the shape of a line that curves up at both ends, similar in shape to a bathtub. The curve has 3 regions:

1. The first region has a decreasing failure rate due to early failures.

2. The middle region has a constant failure rate due to random failures.

3. The last region has an increasing failure rate due to wear-out failures.

Bathtub curve

See the Distributions section for more information on various types of distributions that can be used to characterize interrupts.