System

{{entity:Fusion Reactor Control System}} — interim QC pass on a 239-requirement, 8-subsystem project (baseline BL-25). The project was previously marked qc-reviewed at session 393 but a follow-on decomposition run introduced ghost trace links and spray patterns that the quality tools surfaced on re-lint.

Findings

Ghost trace links (21 removed). The trace graph contained 21 links pointing to requirement IDs in the REQ-SEFUSIONREACTORCONTROLSYSTEM-030 through -104 range that do not exist in the project. These were silently carried as dangling pointers across several sessions. The airgen trace linksets list command exposed them because the targets appeared in the linkset JSON but could not be resolved to actual requirements. All 21 were deleted.

Spray patterns (4 SYS requirements flagged, 67 links missing rationale). Four system requirements — {{sys:SYS-REQ-001}} (plasma equilibrium), {{sys:SYS-REQ-002}} (disruption detection), {{sys:SYS-REQ-003}} (power regulation), and {{sys:SYS-REQ-004}} (SCRAM) — each had 8–34 subsystem derivation links with no rationale text. {{sys:SYS-REQ-004}}‘s 34-link fan-out was the most severe. After removing 1 spurious link (ICRH VSWR protection, derived from its own heating SYS requirement) and the 14 ghost links, 19 genuine SCRAM derivations remained; all received rationale documenting the specific SCRAM budget allocation, SIL-3 independence requirement, or safe-state contribution driving each link. The remaining 27 links across SYS-REQ-001/002/003 were similarly annotated. Total: 37 rationales written.

Ontological mismatch: Biological/Biomimetic on {{entity:disruption prediction engine}}. The {{entity:disruption prediction engine}} carried hex {{hex:51F77B19}} with {{trait:Biological/Biomimetic}} active — a clearly wrong classification for an FPGA-based LSTM inference engine. Reclassification with full context (FPGA deterministic inference, 128-element MHD sensor array, 3ms latency bound, no biological components) produced new hex {{hex:50F77319}} with the trait cleared. The lint engine’s concept cache still shows the pre-session hex; this resolves on next cache refresh.

Coverage gaps (4 concepts undecomposed at subsystem level).

• Safe state: {{sys:SYS-REQ-004}} mandated reaching safe state in ≤5 s but no SUB requirement defined the safe-state condition with measurable criteria. REQ-107 created for the {{entity:emergency shutdown system}}, specifying six concrete state variables (plasma current ≤10 kA, NBI beam-off, ICRH/ECRH at 0 W, coil currents ≤10% operating, fuelling locked-closed) and a 10-second confirmation signal.
• Heating systems EMI: {{sys:SYS-REQ-010}} (immunity to ICRH/NBI RF fields) had no SUB implementation. REQ-108 created requiring IEC 61000-4-3 Class 3 shielding with ≥40 dB SNR for Plant I&C cable runs.
• Maintenance bus: {{sys:SYS-REQ-011}} referenced a qualified maintenance bus with no SUB decomposition. REQ-109 created specifying IEC 61784-3 functional safety communications, ≤10 s end-to-end latency, and a five-field message structure for fault reports.
• Pellet injection redundancy: The {{entity:pellet injection controller}} carries the {{trait:System-Essential}} trait (hex {{hex:55F53218}}) but had no redundancy or failover requirement. REQ-110 created requiring dual-redundant warm standby with 2-second switchover, ±1 K cryostat state retention, and ≥50% injection rate in degraded mode.

Standards reference gap: {{entity:fuel inventory controller}}. UHT {{trait:Institutionally Defined}} trait signals regulated institutional context. REQ-111 created requiring compliance with IAEA SSG-52, ITER PDDS-11, IEC 62645, and IAEA INFCIRC/153 tritium accountancy with ≤0.5% inventory uncertainty.

Statistical parameters: {{entity:disruption prediction}}. {{sub:SUB-REQ-010}} stated a 95% true positive rate but lacked confidence interval and sample size. Updated to: 95% CI lower bound at n≥500 disruption events, spanning plasma current 8–15 MA, q95 = 2.5–5.0, and at least 3 MHD stability regimes.

Decomposition

flowchart TB
  n0["Fusion Reactor Control System"]
  n1["Plasma Control System"]
  n2["Disruption Prediction and Mitigation System"]
  n3["Heating and Current Drive Control"]
  n4["Magnet Safety and Protection System"]
  n5["Fuel Injection and Burn Control"]
  n6["Plasma Diagnostics Integration System"]
  n7["Plant Control and I&C System"]
  n8["Interlock and Emergency Shutdown System"]
  n0 -->|contains| n1
  n0 -->|contains| n2
  n0 -->|contains| n3
  n0 -->|contains| n4
  n0 -->|contains| n5
  n0 -->|contains| n6
  n0 -->|contains| n7
  n0 -->|contains| n8

Corrections

Action	Detail
21 ghost links deleted	REQ-SEFUSIONREACTORCONTROLSYSTEM-030 through -104 targets; links created by prior sessions pointing to requirements that were never persisted
1 spurious link removed	{{sys:SYS-REQ-004}} → {{sub:SUB-REQ-029}} (ICRH VSWR protection derives from heating SYS, not SCRAM)
37 link rationales written	All remaining SYS-REQ-001/002/003/004 → SUB derivation links annotated
REQ-107 created	IESS safe-state definition: six measurable state variables + 10s confirmation signal
REQ-108 created	Plant I&C EMI shielding for ICRH/NBI fields (IEC 61000-4-3 Class 3)
REQ-109 created	Qualified maintenance bus (IEC 61784-3, ≤10s, five-field message structure)
REQ-110 created	Pellet injection dual-redundant warm standby (2s switchover, ≥50% degraded rate)
REQ-111 created	Fuel inventory controller regulatory compliance (IAEA SSG-52, INFCIRC/153)
SUB-REQ-010 updated	Disruption prediction statistical test conditions added (n≥500, CI, q-profile range)
DPE reclassified	{{hex:51F77B19}} → {{hex:50F77319}}: Biological/Biomimetic trait removed

Residual

The lint findings for {{trait:Ethically Significant}} on the fusion reactor control system, emergency shutdown system, and safety arbiter remain open. These entities have substantial safety requirements; the lint flag appears because the UHT {{trait:Ethically Significant}} trait triggers on a separate “ethical/rules-of-engagement” check that maps to military-domain concepts not applicable here. No action taken — flagging as informational in next validation.

Next

The Biological/Biomimetic cache refresh will clear on next lint run. The project has 239 requirements, all with rationale and verification, ghost links cleared, and 4 coverage gaps now closed. Ready for SE_VALIDATION.