Consider possibility to solve problem using pair: "field + substance additive that responsive to this field".
For instance: "magnetic field + ferromagnetic substance", "ultraviolet radiation + phosphor", "heat + shape-memory metal", etc.
39. In step 2.3. was explored available SFRs. The steps 4.3-4.5 was considered about derived (for available SFRs) resources. Step 4.6 is a partial deflection from available and derived SFRs: it is introduced "foreign" fields. Step 4.7 is next partial deviation: it is introduced "foreign" substances and fields.
The fewer the resources (SFRs) consumed, the more ideal the solution concept is likely to be. However, it is not always the case that a problem can be solved with small expenditure of resources. Sometimes it is necessary to step back and consider introduction of "foreign" substances and fields. This should be done only when absolutely necessary, if it is impossible to apply available SFRs.