Analysis Phase. Assemble, review and present information relevant to the design and development of the Project, including but not limited to the following:
Analysis Phase. Perform a functional analysis review of the 90% design documents to determine if the Project components achieve the design objectives and identify any high cost and/or low value functions.
Analysis Phase. In the final phase, the synthesised system fault trees are analysed, both qualitatively and quantitatively, and from these results the FMEA is created. Firstly, the fault trees undergo qualitative analysis to obtain their minimal cut sets, which reduces them in size and complexity. This is typically done using a mixture of classical logical reduction techniques, which usually means applying logical rules to reduce complex expressions, and more modern techniques developed specifically for HiP-HOPS. Once the minimal cut sets have been obtained, they are analysed quantitatively, which produces unavailability values for the top events of each fault tree. The last step is to combine all of the data produced into an FMEA, which is a table that concisely illustrates the results. The FMEA shows the direct relationships between component failures and system failures, and so it is possible to see both how a failure for a given component affects everything else in the system and also how likely that failure is. However, a classical FMEA only shows the direct effects of single failure modes on the system, but because of the way this FMEA is generated from a series of fault trees, the HiP-HOPS is not restricted in the same way, and the FMEAs produced also show what the further effects of a failure mode are; these are the effects that the failure has on the system when it occurs in conjunction with other failure modes. Figure 18 shows this concept.
Analysis Phase. In the final phase, the synthesised system fault trees are analysed, both qualitatively and quantitatively, and from these results the FMEA is created. Firstly, the fault trees undergo qualitative analysis to obtain their minimal cut sets, which reduces them in size and complexity. This is typically done using a mixture of classical logical reduction techniques, which usually means applying logical rules to reduce complex expressions, and more modern techniques developed specifically for HiP-HOPS. Once the minimal cut sets have been obtained, they are analysed quantitatively, which produces unavailability values for the top events of each fault tree. The last step is to combine all of the data produced into an FMEA, which is a table that concisely illustrates the results. The FMEA shows the direct relationships between component failures and system failures, and so it is possible to see both how a failure for a given component affects everything else in the system and also how likely that failure is. However, a classical FMEA only shows the direct effects of single failure modes on the system, but because of the way this FMEA is generated from a series of fault trees, the HiP-HOPS is not restricted in the same way, and the FMEAs produced also show what the further effects of a failure mode are; these are the effects that the failure has on the system when it occurs in conjunction with other failure modes. Figure 19 shows this concept. Figure 19 - The conversion of fault trees to FMEA In Figure 19, F1 and F2 are system failures, and C1 – C9 are component failures. For C3, C4, C6 and C7, there are no direct effects on the system – that is, if only one of these components fail, nothing happens. However, they do have further effects; for example, C3 and C4 both occurring in conjunction will cause F1 to occur. The FMEAs produced, then, show all of the effects on the system, either singly or in combination, of a particular component failure mode. This is especially useful because it allows the designer to identify failure modes that contribute to multiple system failures (e.g. C5 in the example). These common cause failures represent especially vulnerable points in the system, and are prime candidates for redundancy or extra reliable components.
Analysis Phase. E.2.1.1 Develop the analysis schedule, describe each session’s objectives and determine participants X
