Scram PJ reach from the bounding-box union of:
- hot-standby box (mode_boundaries.q_shutdown)
- heatup-tight reach envelope (results/reach_heatup_pj_tight.mat)
- operation-LQR reach envelope (results/reach_operation_result.mat)
- LOCA operation envelope (results/reach_loca_operation.mat, 3s)
with precursor + temperature outliers clamped to physical bounds.
Results at probe horizons:
T=10s: 10890 sets in 480s wall — n ∈ [-8e-4, 0.047] T_c [231, 362]
T=30s: 16925 sets in 2892s wall — n ∈ [-4e-4, 0.021] T_c [229, 361]
T=60s: 23919 sets in 705s wall — n ∈ [-2e-4, 0.009] T_c [226, 359]
Monotone n decay, factor-of-5-per-minute even from the wide union.
This is the defensible scram-obligation version: starts from anywhere
the plant could plausibly be (including LOCA-perturbed operation
state), proves n decays. X_exit(scram)=n≤1e-4 still not reached in
60s — same T_max-vs-plant-decay mismatch previously flagged.
Fixed: missing Printf import that had failed the summary block on the
first run (results still computed correctly, just the final print
errored; the matwrite is after the print so the mat file wasn't
saved on that run).
Journal entry for 2026-04-21 extended with the fat-entry result +
the LOCA-reach 3s-horizon numerical-looseness apass. 38 pages.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Morning-review items 2 and 3.
Point 2 (scram X_entry expansion):
- reach_loca_operation.jl: LQR reach under Q_sg widened to
[0, 1.5*P_0] (steam-line break envelope) for 3 s horizon.
Longer horizons cause numerical blowup in the box-hull
reach propagator due to slow precursor modes amplifying
under large disturbance — documented in the script.
- reach_scram_pj_fat.jl: computes bounding-box union of
hot-standby + heatup-tight + operation + LOCA reach
envelopes, clamps obvious numerical outliers on precursors
and temperatures, builds a fat X_entry(scram), runs scram
PJ reach. Result pending (TMJets compiling).
Point 3 (heatup steam-dump Q_sg):
- configs/heatup/with_steam_dump.toml: Q_sg ∈ [0, 0.05·P_0]
as bounded parameter.
- reach_heatup_pj_sd.jl: 12-state RHS with x[10]=Q_sg (dx=0,
augmented bounded param) and x[11]=t. Running in
background.
Tight-entry heatup via the new TOML-config reach_heatup_pj.jl
reproduces the previous all-6-halfspaces-discharged result
(300s horizon, T_c envelope [281.05, 291.0]). Refactor
preserves semantics.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Architecture restructure from morning review:
1. code/scripts/ subdivided into sim/, reach/, barrier/, plot/.
Easier nav; `barrier/` is the natural place for SOS scale-up scripts.
2. Heatup PJ reach variants consolidated behind TOML configs.
reach_heatup_pj.jl now takes `--config path/to/config.toml`;
configs/heatup/baseline.toml (wide entry, from predicates.json) and
configs/heatup/tight.toml (narrow entry, reproduces all-6-halfspaces
discharged result). Old reach_heatup_pj_tight.jl and
reach_heatup_pj_tight_full.jl deleted (superseded).
3. Reach output .mat files moved from reachability/ to results/.
reachability/ now = specs + docs; results/ = ephemeral outputs
(gitignored *.mat). README added.
4. OVERNIGHT_NOTES.md archived to claude_memory/2026-04-20-21-overnight-
session-summary.md (date range in the filename makes the history clearer).
All include() / Pkg.activate() paths in scripts updated for the new
depth. Smoke tests pass (reach_operation.jl generates its .mat in
the new results/ location; sim_sanity.jl matches MATLAB).
Presentation outline for the 20-min prelim talk landed in
presentations/prelim-presentation/outline.md. 14-slide assertion-
evidence format targeting OT-informed cybersecurity audience. Each
slide: one declarative assertion + one figure. Outline includes
which figures already exist and which need to be created, timing
checkpoints, cybersecurity angle to emphasize, and Q&A prep.
New config configs/heatup/with_steam_dump.toml + its companion
scripts/reach/reach_heatup_pj_sd.jl (12-state RHS with Q_sg as an
augmented bounded parameter x[10] and time as x[11]). Kicks off
point 3 from morning review.
Next up: scram X_entry expansion (morning point 2) — LOCA scenario
+ union of mode reach envelopes.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Polytopic (Nagumo face-by-face LP check) and SOS polynomial
(Prajna-Jadbabaie w/ CSDP) barrier attempts on operation mode.
**Polytopic (barrier_polytopic.jl):** the naive check on
inv2_holds ∩ precursor_tube_bounds fails — 16 of 18 faces can be
crossed under A_cl. This is EXPECTED: safety halfspaces alone form
a set too big for LQR to contract from everywhere. The correct
approach is Blanchini's pre-image iteration (max robustly controllable
invariant set). Sketched in the script; 2-3 days to implement properly.
**SOS (barrier_sos_2d.jl):** a working proof of concept.
CSDP returns OPTIMAL on a 2-state projection of the operation mode
(dn, dT_c) with:
X_entry = |dn| ≤ 0.01, |dT_c| ≤ 0.1
X_unsafe = dn ≥ 0.15 (high-flux-trip direction)
Dynamics = reduced 2×2 A_cl after LQR.
No disturbance (B_w projects to 0 in this subset).
Global decrease condition (-(∇B·f) SOS) instead of Putinar ∂{B=0}.
Result: a degree-4 polynomial B(x) satisfying all three barrier
conditions. Coefficients printed. First non-quadratic barrier
artifact for this plant.
Caveats:
- 2D projection loses precursor coupling.
- Disturbance ignored in this projection.
- Global-decrease is stronger than the Putinar ∂{B=0} condition;
the latter requires bilinear σ_b·B formulation (BMI) and
iterative solvers. Deferred.
- Scaling to 10-state degree-4 gives SDP ~ 1000×1000; CSDP may
choke. Mosek or MOSEK-free SDP (SCS) might handle.
JuMP, HiGHS, SumOfSquares, DynamicPolynomials, CSDP all added to
Project.toml.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Following user's review feedback (point 1):
prompt_critical_margin_heatup: a new entry under safety_limits that
proves the PJ reduction's validity condition (beta - rho > 0 with
margin) rather than hand-waving it. Controller-specific
specialization for heatup: under feedback linearization,
rho_total = Kp*(T_ref - T_c), so rho ≤ 0.5*beta iff T_c ≥ T_ref -
32.5. Worst-case T_ref = T_c0 at ramp end, so T_c ≥ 275.85 is
sufficient, which our tight-entry reach clears trivially.
Conjoined into inv1_holds. Safety proofs now target BOTH the
physical bounds AND the conditions that make the PJ approximation
sound. Saves Dane's rigor-over-vibes instinct (saved to memory).
plot_reach_tubes.jl: four-panel visualization of a reach-result .mat:
(1) T_c / T_hot / T_cold envelopes overlaid
(2) ΔT_core = T_hot - T_cold (power proxy, right-axis MW)
(3) rho envelope in dollars, with ±1$ prompt lines
(4) n envelope
Operation-mode plot saved to docs/figures/reach_operation_tubes.png.
Heatup PJ version pending — needs full per-step data from the
running reach_heatup_pj_tight_full.jl.
reach_heatup_pj.jl + reach_heatup_pj_tight_full.jl now save
per-timestep envelopes (t_arr, Tc_lo_ts, Tc_hi_ts, ...) so the
plotting script can overlay tubes vs time.
Next up: polytopic / SOS barriers, Tikhonov error bound for PJ.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
- OVERNIGHT_NOTES.md: read-this-first TL;DR for morning review.
Points at journal.pdf (32 pages, latest entry has all results),
validate_pj_heatup.png, and the Pluto app. Lists priority-1 actions
(look at data, decide on refinement vs accept-300s-tube) and
priority-2 followups (scram reach ingestion, entry refinement,
saturation hybrid, SOS barriers, alpha parametric).
- reach_heatup_pj_tight.jl: script committed but not yet run tonight.
Tighter X_entry on T_c (width 6 K vs baseline 14 K) to test whether
the low-T_avg-trip tube-looseness is entry-box-width driven or
reach-growth driven.
Scram PJ still compiling as of this commit; will land separately
when it completes.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Results from the overnight TMJets run with the prompt-jump model:
T=60s: PASSES (10,044 reach-sets, 205 s wall)
T=300s: PASSES (27,375 reach-sets, 591 s wall)
T=1800s+: partial — exhausts 100k step budget past ~300s
At T=300s the envelope is:
n: [-0.00156, 0.0103] (slightly negative = sound overapprox)
T_c: [272.4, 295.0] C
T_f: [261.2, 302.7] C
T_cold: [270.0, 289.5] C
Discharges 5/6 inv1_holds safety halfspaces at 300s:
fuel_centerline: +897 K margin ✓
t_avg_high_trip: +25 K margin ✓
t_avg_low_trip: VIOLATED (tube dips to 272.4, limit 280)
n_high_trip: huge margin ✓
cold_leg_subcooled: +15 K margin ✓
The low_trip violation is TUBE looseness, not physical — nominal sim
only dips to ~280 transiently. Fixable by tighter X_entry, higher
orderQ, or refinement. Open item.
Journal updated with full results table + limitation box. scram PJ
reach ready to run but not yet executed (structure similar, simpler).
Fix: siunitx \degreeFahrenheit, \degree, \microsecond now work via
\DeclareSIUnit in preamble. UTF-8 passthrough in listings via
literate= map for Δ, λ, μ, α, β, ρ, Σ, Λ, ≤, ≥, →, ±, °, ×, ε.
Journal now compiles clean: 32 pages, 0 errors.
App v2 Pluto cells land under §§9b–9d: live reach-result ingestion
with computed per-halfspace margins, 2D projection chooser, PJ-reach
overlay placeholder.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Singular-perturbation reduction of the PKE+T/H system: set dn/dt=0,
solve algebraically n = Λ·Σλ_i·C_i / (β-ρ). State drops 10 -> 9 (no
n), removes Λ⁻¹ stiffness. Validated against full state on the heatup
scenario:
t [s] |Δn|/n_full T_c err [K]
60 3.7e-5 4e-6
300 3.8e-4 1.9e-4
1200 1.0e-3 2.2e-3
3000 5.0e-4 7.2e-3
Maximum relative error 0.1% on n, peak 7 mK on temperatures over
50 minutes. PJ approximation is excellent for slow heatup transients
(sub-prompt-critical regime).
Files:
- code/src/pke_th_rhs_pj.jl: reduced 9-state RHS
- code/scripts/validate_pj.jl: side-by-side sim
- code/scripts/reach_heatup_pj.jl: TMJets reach with PJ model
(probing T = 60, 300, 1800, 5400 s)
App v2 (Pluto):
- §9b: live ingestion of reach_operation_result.mat with per-
halfspace margins computed from JSON-defined inv2_holds.
- §9c: 2D projection chooser (n, T_f, T_c, T_cold) with reach
tube envelope overlay.
- §9d: PJ heatup reach summary (placeholder until first run lands).
Journal:
- Added 2026-04-20-overnight-prompt-jump.tex with PJ derivation,
validation table, soundness ledger update. apass markers for
the in-progress reach results.
This commit captures state mid-run; next commit will add the
populated reach results once TMJets returns.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Records the journal scaffold + retroactive-entries + Julia migration
+ Pluto app work, with \apass{} markers for content that should be
expanded in a later A-pass. Keeps the discipline going from the
night the journal stood up.
Easter eggs:
- ASCII reactor + primary loop in journal/README.md (subtle, shows
where Q_sg flows in as a disturbance).
- Garden-lyric reference embedded in pke_params.jl docstring
("looks ordinary on the surface but is something else underneath")
— same lyric as the preamble.tex comment, referencing the name
behind Split. Hacker-Split's signature.
- 🦎 in the Pluto notebook header + closer.
Nothing functional, nothing that clutters the substance.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Full toolchain port. Numerical equivalence verified against MATLAB:
- main_mode_sweep.jl: every mode's final state matches MATLAB to 3-4 dp
- reach_operation.jl: per-halfspace margins match MATLAB exactly
- barrier_lyapunov.jl: per-halfspace bounds match (best Qbar from sweep
yields max|dT_c| = 33.228 K either side)
- barrier_compare_OL_CL.jl: OL gamma 1.038e13, CL gamma 1.848e4
matching the MATLAB result; LQR helps by ~20,000x on every halfspace.
Phase summary:
Phase 1: pke_solver.jl, plot_pke_results.jl (Plots.jl), main_mode_sweep.jl
Phase 2: reach_linear.jl, reach_operation.jl, barrier_lyapunov.jl,
barrier_compare_OL_CL.jl, load_predicates.jl
Phase 3 (this commit): delete plant-model/ entirely, delete reach
code from reachability/ keeping predicates.json + docs,
git mv julia-port/ -> code/, update root README + CLAUDE,
write code/CLAUDE.md and code/README.md, update reach
README + WALKTHROUGH file paths, journal preamble note
that pre-port entries reference MATLAB paths.
Why now: prompt-neutron stiffness in nonlinear reach made it clear we
need TMJets, which is Julia. Already had the Julia plant model
working and matching MATLAB. Two languages = two sources of truth =
two places to drift. One language, one truth.
Manifest.toml gitignored. .mat results gitignored.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
