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Planar X-ray Radiography L1-031

Medical ImagingProjection X-ray diagnostic imagingδ=3 · standardL_DAG = 2.5📋 Stub — not mineable
📋

Unclaimed Principle — open for contribution

This Principle is declared in the catalog but has no reference solver, no pinned dataset, and is not registered on-chain. There is no reward pool. Submitting a cert against this Principle today will record the cert for reproducibility but pay zero PWM.

To claim it as a Bounty #7 contribution: open a PR adding (1) a reference solver, (2) ≥1 dataset pinned to IPFS, (3) updates to the L3 manifest with dataset CIDs. After verifier-agent triple-review, the founders' 3-of-5 multisig signs PWMRegistry.register() and the Principle becomes mineable.

Forward model E

Planar X-ray Radiography: xray projection produces the measurement through a 3-node primitive DAG L.xray_source -> L.beer_lambert -> int.spatial, with spatially-projected accumulation and photon-shot-noise-limited (Poisson counting). Recovery is posed as a linear inverse problem that inverts the forward operator to estimate the scene-side 2D attenuation projection. Difficulty tier delta=3 with effective condition number kappa_eff~8; calibration-level mismatch (scatter, patient_motion, anti_scatter_grid) sets the accuracy floor at the Omega boundary. See the forward_model field for the closed-form imaging equation.

L-DAG

L.xray_source -> L.beer_lambert -> int.spatial
L.xray_sourceL.beer_lambertint.spatial

Well-posedness W

Existence:
true
Uniqueness:
true
Stability:
conditional
κ:
160

Existence of the recovered 2D attenuation projection is guaranteed within the declared Omega bounds. Uniqueness holds on the measurement-supported subspace; out-of-support modes are controlled by the declared priors. Stability is well-conditioned (kappa_eff ~= 8); scatter dominates the stability cliff; patient_motion and the remaining mismatch parameters contribute higher-order bias terms. Photon-shot-noise-limited (poisson counting) sets the irreducible data-fidelity floor, while mild Tikhonov or analytic inversion is sufficient at the nominal Omega point.

Solvability C

Solver class:
analytic / closed-form + post-processing [LogTransform] | linear-operator + convex optimisation [Scatter-Correct] | linear-operator + deep neural prior [XR-Net]
Convergence rate q:
2
Complexity:
O(H * W * log(...)) per iteration; learned variants: O(H W Z * F_theta_cost) per forward pass

Specs (0)

No L2 specs registered yet for this principle.