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 Old reach_heatup_pj_tight.jl and reach_heatup_pj_tight_full.jl deleted (superseded). 3.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>
code
Plant model, controllers, and reach-analysis toolchain for the HAHACS preliminary example. All Julia.
What this is
A 10-state coupled neutronics + thermal-hydraulics model (point kinetic equations + lumped thermal loop) with continuous-mode controllers for each of the DRC modes (shutdown, heatup, operation, scram), plus a hand-rolled linear reach-tube propagator, a Lyapunov-ellipsoid barrier attempt, and scaffolding for TMJets-based nonlinear reach.
Ported from MATLAB on 2026-04-20 once the reach experiments made it
clear that Julia's stack (OrdinaryDiffEq, MatrixEquations,
ReachabilityAnalysis, LazySets, @taylorize) was the right tool
for everything we need going forward. The MATLAB originals are in
the git history.
Running
First time:
cd code
julia --project=. -e 'using Pkg; Pkg.instantiate()'
Subsequent:
julia --project=. scripts/main_mode_sweep.jl # all 5 DRC modes, figures
julia --project=. scripts/reach_operation.jl # operation-mode linear reach
julia --project=. scripts/barrier_lyapunov.jl # Lyapunov barrier attempt
julia --project=. scripts/barrier_compare_OL_CL.jl # OL vs CL barrier
julia --project=. scripts/reach_heatup_nonlinear.jl # nonlinear heatup (10s cap)
Figures save to ../docs/figures/. Reach results save to
../reachability/*.mat (gitignored).
Structure
See CLAUDE.md for the architectural overview and ../journal/ for
the invention-log-style narrative of how this code got written.
Dependencies
From Project.toml:
OrdinaryDiffEq— ODE solver, Rodas5 for stiff systems.MatrixEquations—arecfor LQR Riccati,lyapcfor Lyapunov.ReachabilityAnalysis+LazySets— reach sets and set operations.Plots— figures (GR backend by default).JSON— read../reachability/predicates.json.MAT— save results.
Manifest.toml is gitignored; regenerate locally on first
Pkg.instantiate().