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Source changed 2026-10-03 02:22:15 UTC · snapshot created 2026-10-03 03:38:22 UTC · last check 2026-10-03 05:10:10 UTC

SYSE-CARD-02 — Develop a problem portfolio and System family without freezing either

  • Situation: A prototype or operating observation changes which problem is worth solving, while an attractive system option may be difficult to realize with the available means.
  • Question: Should the next change concern the problem, the system option, its builder arrangement, or a combination?
  • First useful result or blocker: Comparable options and a choice, a worthwhile probe, rejection of the set, or the missing question or authority.
  • Start with: SYSE.22 when project focus and use are understood. Resolve an ambiguous system through SYSE.1 and incomparable configurations through SYSE.13.
  • Stop or return: Stop at a useful option decision if realization does not change it. Use SYSE.23 when the relation between the option and its builder changes the next investment or reconfiguration choice.

APP-SYSE-02 considers inspection systems whose relevant problems include early damage, false alarms, inaccessible locations and interruption of operation. SYSE.22 keeps the problem formulations connected to, but distinct from, the system-family options. SYSE.2 supplies their intended uses; SYSE.5 and SYSE.6 supply materially different arrangements; SYSE.7 and SYSE.13 keep descriptions and configurations comparable. SYSE.10 interprets what a prototype or trial actually supports.

These contributions allow SYSE.22 to choose among surviving options, reject them, or select a feasible probe whose result could change the choice enough to justify its cost. For example, a trial revealing inaccessible locations can change the use question and the relevant sensing options. Repeating the old ranking with unchanged acceptance conditions would miss that change. The new question returns to the linked use and system concepts before their architectures are compared again.

A surviving option can instead be blocked by the arrangement that builds or supports it. SYSE.3 makes that dependency explicit; SYSE.12 identifies the platform contribution. SYSE.23 then compares changing the option, changing the builder arrangement, changing both, and retaining the present arrangement. The next result is an investment or reconfiguration choice. SYSE.20 distinguishes work that can overlap from contributions that must be available first. Developing a problem, a system and its builder therefore need not become three consecutive project stages.

A source change returns through SYSE.19 to the decisions that relied on it.