Lesson

C1 Distinguish Facts, Constraints and Preferences

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One Shop-Floor Request Can Contain Several Decisions

“Give this machine less work today and prioritize a key customer” combines potentially different meanings. The first part may reflect maintenance or a risk preference. The second may mean a firm delivery commitment or a sequencing preference. Clarifying the reason prevents every judgment from becoming a permanent restriction.

Use six statements from a teaching workshop.

Statement	Initial classification	Clarify
WC-1 can only process A	Resource and routing fact	Approved alternative routes
WC-1 has two hours of maintenance today	Calendar fact	Whether capacity already reflects it
Schedule at most 300 units of A today	Management rule or model constraint	Reason, object and effective period
Prefer fewer color changes	Objective preference	Color mapping, changeover measure and optimization direction
Keep started tasks unchanged	Execution-stability rule	Frozen fields and duration
Approve overtime when overloaded	Operational action	Approver and additional availability

Map the Meaning to the Toolkit

The standardized interface represents processes, resources, calendars, quantities and materials. objective_system organizes objective direction, weights and scope. marginal_control handles explicit rules, allowances and operational control information. A rule also needs appropriate adaptation and execution checks to affect solving.

Classify by meaning, not wording. A 300-unit limit caused by physical capability belongs in resource data. The same limit arising from a current allocation agreement needs a scope and expiry. Its origin determines how it should be maintained.

Separate Hard Conditions from Costs

A hard condition must hold for every accepted plan. A soft condition allows deviation and represents its cost through defined penalties or objective measures. Soft capacity can produce an overloaded candidate; the user needs to see the affected resource and period and decide how it could be handled.

Objective weights do not automatically enlarge the feasible set. If every commitment has a hard deadline and resources are insufficient, increasing a delivery weight cannot resolve the conflict.

Prepare a Configuration Record

For each requirement, record the original statement, confirmed meaning, data or configuration location, scope, owner and review method. Keep the business rationale readable while retaining exact field and interface names.

After changing a rule, check whether the same limit remains in data, a recipe or the application. Duplicated restrictions can explain why relaxing one setting appears to have no effect.

Exercise and Suggested Answer

Split “prioritize the urgent order without changing started work” into two requirements. Specify the urgent order and its deadline, then define what remains frozen. If they conflict, show the resource and period conflict and ask the responsible person which commitment can change.

Produce a requirements classification table. A reader should understand why each item belongs where it does and who updates it when the business changes.

One Shop-Floor Request Can Contain Several Decisions

Map the Meaning to the Toolkit

Separate Hard Conditions from Costs

Prepare a Configuration Record

Exercise and Suggested Answer

Further Reading