{"artifact_id":"L1-060","layer":"L1","title":"MR Fingerprinting (MRF)","domain":"Medical Imaging","sub_domain":"Pseudo-random acquisition with dictionary matching for T1/T2/rho","physics_fingerprint":{"L_DAG":4.5,"title":"MR Fingerprinting (MRF)","domain":"Medical Imaging","carrier":"radio_wave","primitives":["L.rf_excitation_pseudorandom","L.kspace_undersample","L.dict_match","int.temporal"],"sub_domain":"Pseudo-random acquisition with dictionary matching for T1/T2/rho","noise_model":"gaussian","problem_class":"nonlinear_inverse","solution_space":"4D_parameter_maps","difficulty_delta":10,"integration_axis":"temporal","sensing_mechanism":"mri_fingerprinting"},"observable_profile":{"metric":"PSNR_dB","regime":"Existence of the recovered 4D parameter maps is guaranteed within the declared Omega bounds. Uniqueness is local rather than global (non-convex landscape); convergence depends on initialisation and priors. Stability is moderately conditioned (kappa_eff ~= 25); B0_inhomogeneity dominates the stability cliff; undersampling_artifacts and the remaining mismatch parameters contribute higher-order bias terms. Additive gaussian thermal/electronic noise sets the irreducible data-fidelity floor, while TV / wavelet-sparsity / deep priors stabilise recovery at the ill-conditioned end of Omega.","secondary":"SSIM"},"size_tiers":{"center_spec":{"omega":{"H":256,"W":256,"Z":32,"SNR_dB":18,"motion":0.0,"N_frames":1000,"TR_ms_variable":true,"partial_volume":0.0,"B0_inhomogeneity":0.0,"undersampling_artifacts":0.0},"input_format":"measurement_only","problem_class":"mrf","forward_operator":"mrf_forward","epsilon_fn_center":"18.0"},"omega_bounds":{"H":64,"W":64,"Z":[4,64],"SNR_dB":[0.0,30.0],"motion":[0.0,0.3],"N_frames":[100,5000],"partial_volume":[0.0,0.3],"B0_inhomogeneity":[0.0,0.3],"undersampling_artifacts":[0.0,0.5]},"epsilon_bounds":{"psnr_db":[5.0,45.0]},"allowed_problem_classes":["mrf"],"allowed_omega_dimensions":["H","W","Z","N_frames","TR_ms_variable","SNR_dB","B0_inhomogeneity","undersampling_artifacts","partial_volume","motion","B0_inhomogeneity","undersampling_artifacts","partial_volume","motion"],"allowed_forward_operators":["mrf_forward"]},"hardness_fn":{"type":"epsilon_fn","delta":10,"kappa":500,"metric":"PSNR_dB"},"initiator_dataset":[{"name":"primary","weight":1.0,"ipfs_cid":null,"license_hash":null}],"status":"testnet","staked_pwm":0.0,"chain_hash":"0x805d539964b777fbc574e4af2e24fa558651f1481aed5d845c5509e00fccd209","chain_tx_hash":"0x6f0ed8273e59ffe3fe9d4628a7e765a2e0dd618c7a34227f3228382923983379","chain_block":41553386}