{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2012:LYV4Q7EUJ5VHW2CSVL24FCIHOH","short_pith_number":"pith:LYV4Q7EU","canonical_record":{"source":{"id":"1203.4451","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.geo-ph","submitted_at":"2012-03-20T14:35:04Z","cross_cats_sorted":["math.NA","math.OC"],"title_canon_sha256":"fac92e9dc3ded3a717f457a9f088ac87151507e73e4cd79e85dfcb045add2175","abstract_canon_sha256":"a2f20637babe67e582450627fdc7e47c9f0de6a75537e9086bd515419e0922e7"},"schema_version":"1.0"},"canonical_sha256":"5e2bc87c944f6a7b6852aaf5c2890771f7a894c31f93c6c9f352346d6b99ca6a","source":{"kind":"arxiv","id":"1203.4451","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1203.4451","created_at":"2026-05-18T03:58:25Z"},{"alias_kind":"arxiv_version","alias_value":"1203.4451v2","created_at":"2026-05-18T03:58:25Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1203.4451","created_at":"2026-05-18T03:58:25Z"},{"alias_kind":"pith_short_12","alias_value":"LYV4Q7EUJ5VH","created_at":"2026-05-18T12:27:14Z"},{"alias_kind":"pith_short_16","alias_value":"LYV4Q7EUJ5VHW2CS","created_at":"2026-05-18T12:27:14Z"},{"alias_kind":"pith_short_8","alias_value":"LYV4Q7EU","created_at":"2026-05-18T12:27:14Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2012:LYV4Q7EUJ5VHW2CSVL24FCIHOH","target":"record","payload":{"canonical_record":{"source":{"id":"1203.4451","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.geo-ph","submitted_at":"2012-03-20T14:35:04Z","cross_cats_sorted":["math.NA","math.OC"],"title_canon_sha256":"fac92e9dc3ded3a717f457a9f088ac87151507e73e4cd79e85dfcb045add2175","abstract_canon_sha256":"a2f20637babe67e582450627fdc7e47c9f0de6a75537e9086bd515419e0922e7"},"schema_version":"1.0"},"canonical_sha256":"5e2bc87c944f6a7b6852aaf5c2890771f7a894c31f93c6c9f352346d6b99ca6a","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T03:58:25.960606Z","signature_b64":"B7xOZotEqQVEqXFUm4vWhzFrvGUwebSiRZIxQNgUYF/YBaDDp8du4y4kU/Y3tdC3BIEllcltY4Gb/Dk9DCDVDg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"5e2bc87c944f6a7b6852aaf5c2890771f7a894c31f93c6c9f352346d6b99ca6a","last_reissued_at":"2026-05-18T03:58:25.959827Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T03:58:25.959827Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1203.4451","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T03:58:25Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"MYwcEYmAsPKMRRJKOdiPsfIYuuGI7pkh2mtAwRvEyErptpef7vYceZ99Nsd2UBk0DpS9JimizagezMVajjrgDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T21:16:05.091745Z"},"content_sha256":"0fe54a718099222bc9f676dabf1e3b36b2fa018b9c9c09aa445bc265554a1b44","schema_version":"1.0","event_id":"sha256:0fe54a718099222bc9f676dabf1e3b36b2fa018b9c9c09aa445bc265554a1b44"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2012:LYV4Q7EUJ5VHW2CSVL24FCIHOH","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Iterative algorithms for total variation-like reconstructions in seismic tomography","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["math.NA","math.OC"],"primary_cat":"physics.geo-ph","authors_text":"Caroline Verhoeven, Ignace Loris","submitted_at":"2012-03-20T14:35:04Z","abstract_excerpt":"A qualitative comparison of total variation like penalties (total variation, Huber variant of total variation, total generalized variation, ...) is made in the context of global seismic tomography. Both penalized and constrained formulations of seismic recovery problems are treated. A number of simple iterative recovery algorithms applicable to these problems are described. The convergence speed of these algorithms is compared numerically in this setting. For the constrained formulation a new algorithm is proposed and its convergence is proven."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1203.4451","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T03:58:25Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"KTWw+ZzzJSWIvtezNJcmB0TW38tcXaQm9sHcz0OWKCbJbl79WCrAI721nyr4yE71AuFenxpomvOVus62DmfpBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T21:16:05.092458Z"},"content_sha256":"7fdaddbb526fe49ffe741946cd90860fe81c24952a04cc8a19b01fbf0aa0204a","schema_version":"1.0","event_id":"sha256:7fdaddbb526fe49ffe741946cd90860fe81c24952a04cc8a19b01fbf0aa0204a"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/LYV4Q7EUJ5VHW2CSVL24FCIHOH/bundle.json","state_url":"https://pith.science/pith/LYV4Q7EUJ5VHW2CSVL24FCIHOH/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/LYV4Q7EUJ5VHW2CSVL24FCIHOH/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-05-28T21:16:05Z","links":{"resolver":"https://pith.science/pith/LYV4Q7EUJ5VHW2CSVL24FCIHOH","bundle":"https://pith.science/pith/LYV4Q7EUJ5VHW2CSVL24FCIHOH/bundle.json","state":"https://pith.science/pith/LYV4Q7EUJ5VHW2CSVL24FCIHOH/state.json","well_known_bundle":"https://pith.science/.well-known/pith/LYV4Q7EUJ5VHW2CSVL24FCIHOH/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2012:LYV4Q7EUJ5VHW2CSVL24FCIHOH","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"a2f20637babe67e582450627fdc7e47c9f0de6a75537e9086bd515419e0922e7","cross_cats_sorted":["math.NA","math.OC"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.geo-ph","submitted_at":"2012-03-20T14:35:04Z","title_canon_sha256":"fac92e9dc3ded3a717f457a9f088ac87151507e73e4cd79e85dfcb045add2175"},"schema_version":"1.0","source":{"id":"1203.4451","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1203.4451","created_at":"2026-05-18T03:58:25Z"},{"alias_kind":"arxiv_version","alias_value":"1203.4451v2","created_at":"2026-05-18T03:58:25Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1203.4451","created_at":"2026-05-18T03:58:25Z"},{"alias_kind":"pith_short_12","alias_value":"LYV4Q7EUJ5VH","created_at":"2026-05-18T12:27:14Z"},{"alias_kind":"pith_short_16","alias_value":"LYV4Q7EUJ5VHW2CS","created_at":"2026-05-18T12:27:14Z"},{"alias_kind":"pith_short_8","alias_value":"LYV4Q7EU","created_at":"2026-05-18T12:27:14Z"}],"graph_snapshots":[{"event_id":"sha256:7fdaddbb526fe49ffe741946cd90860fe81c24952a04cc8a19b01fbf0aa0204a","target":"graph","created_at":"2026-05-18T03:58:25Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"A qualitative comparison of total variation like penalties (total variation, Huber variant of total variation, total generalized variation, ...) is made in the context of global seismic tomography. Both penalized and constrained formulations of seismic recovery problems are treated. A number of simple iterative recovery algorithms applicable to these problems are described. The convergence speed of these algorithms is compared numerically in this setting. For the constrained formulation a new algorithm is proposed and its convergence is proven.","authors_text":"Caroline Verhoeven, Ignace Loris","cross_cats":["math.NA","math.OC"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.geo-ph","submitted_at":"2012-03-20T14:35:04Z","title":"Iterative algorithms for total variation-like reconstructions in seismic tomography"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1203.4451","kind":"arxiv","version":2},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:0fe54a718099222bc9f676dabf1e3b36b2fa018b9c9c09aa445bc265554a1b44","target":"record","created_at":"2026-05-18T03:58:25Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"a2f20637babe67e582450627fdc7e47c9f0de6a75537e9086bd515419e0922e7","cross_cats_sorted":["math.NA","math.OC"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.geo-ph","submitted_at":"2012-03-20T14:35:04Z","title_canon_sha256":"fac92e9dc3ded3a717f457a9f088ac87151507e73e4cd79e85dfcb045add2175"},"schema_version":"1.0","source":{"id":"1203.4451","kind":"arxiv","version":2}},"canonical_sha256":"5e2bc87c944f6a7b6852aaf5c2890771f7a894c31f93c6c9f352346d6b99ca6a","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"5e2bc87c944f6a7b6852aaf5c2890771f7a894c31f93c6c9f352346d6b99ca6a","first_computed_at":"2026-05-18T03:58:25.959827Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:58:25.959827Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"B7xOZotEqQVEqXFUm4vWhzFrvGUwebSiRZIxQNgUYF/YBaDDp8du4y4kU/Y3tdC3BIEllcltY4Gb/Dk9DCDVDg==","signature_status":"signed_v1","signed_at":"2026-05-18T03:58:25.960606Z","signed_message":"canonical_sha256_bytes"},"source_id":"1203.4451","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:0fe54a718099222bc9f676dabf1e3b36b2fa018b9c9c09aa445bc265554a1b44","sha256:7fdaddbb526fe49ffe741946cd90860fe81c24952a04cc8a19b01fbf0aa0204a"],"state_sha256":"5ec5f0911cc1e576a7258996c2f0a5053a7b558f438d912047d92ee4a4a26387"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"WcwteCd1CMGHwhcEp65ff7mj2BzJ38/WZHby65VFbw1peyJD0YVFydEVAnCrjCykGQujvlwZ2ZjUaNn1Ip4NDg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-28T21:16:05.097296Z","bundle_sha256":"7cd86a10908bede09f5d12aa31c88022a17dec7f6a06aa0a898adead5b940a30"}}