Design considerations reliability factor

HMI is the human to machine interface in a system. It is the operator interface or UI, which in modern systems is typically a computer screen with computer input-output controls for the operator. HMI is also the application of human factors and human engineering to system design to ensure the safe and reliable operation of the system throughout its life cycle. Since personnel are a major component of any system, special design consideration must be given to human performance. HMI is also sometimes referred to as MMI. HMI is identical to the more recent term HSI. 

There are many other factors that can affect the performance and on-vehicle reliability of activated carbon canisters. The following items shown in Table 6 represent some of the more important factors that must be taken into consideration when designing an evaporative emission canister. 

Consider a task analysis for Do-ability. Can the operators do what we have asked them to do Tasks and facilities should be designed with knowledge of ergonomic considerations and performance shaping factors (PSF) so that operator reliability can be designed into the task. 

Because of liquid-dispersion difficulties in packed towers, the design of plate towers is considerably more reliable and requires less safety factor when the ratio of liquid mass velocity to gas mass velocity is low. 

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