OPS.10.2:11 - SoTA-Echoing

For the question “Can this finite work meet its dates with shared resources?”, adopt explicit interval feasibility and sequence choices. The OR-Tools Job Shop account, variables and constraints supplies precedence and exclusive-resource alternatives; its CP-SAT result definitions distinguish a feasible answer, a proven optimum, proven infeasibility and an unresolved stop. Adapt these constructions in :4.2-4.3 to operating attendance phases and recipient deadlines. A precedence-only forward pass is cheaper and sufficient when resources do not bind. In :5.2 it cannot choose the specialist order, so explicit resource choices earn their added effort. These sources support the formulation and answer distinctions, not a claim that one solver is best for every operation. Reconsider the formulation or search method when problem size or new operating constraints make its cost or representation inadequate.

For calendar feasibility, adopt the explicit distinction between elapsed interval and working duration in IBM’s Scheduling Tutorial, chapter 4. Its example permits suspension during days off and explains separate restrictions on starts, ends and occupied extent. Adapt :4.2 and :4.4 to choose the rule from the operation: :5.4 requires a whole uninterrupted occupation. Combining open hours would answer a different permitted-work question. The extra interval check is small and decides the example; the tutorial does not establish whether a real test may pause. Reopen when interruption, attendance or calendar rules change.

For a known schedule or a named delay scenario, compare an explicit feasible plan with tested reserve against fixed critical-chain and percentage-buffer prescriptions. Herroelen and Leus, On the Merits and Pitfalls of Critical Chain Scheduling, PMI conference paper (2000), sections on critical sequences, buffers and computational experiments, supplies historical counterexample and experimental evidence. Adapt its attention to resource-dependent sequences and schedule revision; reject treating an initially selected chain or a fixed percentage as sufficient protection. This changes :4.4-4.6: preserve useful reservations, compare the delay actually being protected, and recheck resource feasibility after buffer placement. The cost is a more explicit comparison and possible coordination changes. The paper’s old software comparisons and experimental percentages are not present-day performance claims. Reopen when an applicable protection policy meets the same delivery and coordination requirements with better supported burden or outcomes; probabilistic protection requires its own uncertainty basis.