{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:4DPR7YBMOFVK5DI6HIA5F2LMNC","short_pith_number":"pith:4DPR7YBM","canonical_record":{"source":{"id":"1906.01132","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.comp-ph","submitted_at":"2019-06-03T23:53:41Z","cross_cats_sorted":["physics.geo-ph"],"title_canon_sha256":"8e48c8e5d40ceb4a7a98333e1a53e3fb49d558f63710dcb5e65a8e625b8dc48b","abstract_canon_sha256":"c2a9666d586c18b353e834712694625b7d220c4da79acdb4e2ad10017272e4eb"},"schema_version":"1.0"},"canonical_sha256":"e0df1fe02c716aae8d1e3a01d2e96c68a40518956c1ea6376cd55e8c5b102257","source":{"kind":"arxiv","id":"1906.01132","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1906.01132","created_at":"2026-05-17T23:44:17Z"},{"alias_kind":"arxiv_version","alias_value":"1906.01132v1","created_at":"2026-05-17T23:44:17Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1906.01132","created_at":"2026-05-17T23:44:17Z"},{"alias_kind":"pith_short_12","alias_value":"4DPR7YBMOFVK","created_at":"2026-05-18T12:33:10Z"},{"alias_kind":"pith_short_16","alias_value":"4DPR7YBMOFVK5DI6","created_at":"2026-05-18T12:33:10Z"},{"alias_kind":"pith_short_8","alias_value":"4DPR7YBM","created_at":"2026-05-18T12:33:10Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:4DPR7YBMOFVK5DI6HIA5F2LMNC","target":"record","payload":{"canonical_record":{"source":{"id":"1906.01132","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.comp-ph","submitted_at":"2019-06-03T23:53:41Z","cross_cats_sorted":["physics.geo-ph"],"title_canon_sha256":"8e48c8e5d40ceb4a7a98333e1a53e3fb49d558f63710dcb5e65a8e625b8dc48b","abstract_canon_sha256":"c2a9666d586c18b353e834712694625b7d220c4da79acdb4e2ad10017272e4eb"},"schema_version":"1.0"},"canonical_sha256":"e0df1fe02c716aae8d1e3a01d2e96c68a40518956c1ea6376cd55e8c5b102257","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:44:17.751679Z","signature_b64":"rRqNEGa/9cAE4INUI1z3ReCtB0U0qV8V/9AoDqWAxTRhmCw0ZBturnHYpBwWlYNfc4X1gbxL0FE0VT9blOc5Bw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"e0df1fe02c716aae8d1e3a01d2e96c68a40518956c1ea6376cd55e8c5b102257","last_reissued_at":"2026-05-17T23:44:17.751023Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:44:17.751023Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1906.01132","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-17T23:44:17Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"R0WYFr7V1gX8ssH0ZHHJNcj8kmyJZKjwOjS4/3M7r6eYqxrx2+5xY/U2z4aKY2hInqsgJsgl8C9fjVci3THGAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T02:27:56.599655Z"},"content_sha256":"043272e6b673d2e79923e7ce60aa0e831c58bcba440a4e7720527a0711cfe1b4","schema_version":"1.0","event_id":"sha256:043272e6b673d2e79923e7ce60aa0e831c58bcba440a4e7720527a0711cfe1b4"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:4DPR7YBMOFVK5DI6HIA5F2LMNC","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Large-scale Inversion of Subsurface Flow Using Discrete Adjoint Method","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["physics.geo-ph"],"primary_cat":"physics.comp-ph","authors_text":"Daniel O'Malley, Satish Karra, Shu Wang","submitted_at":"2019-06-03T23:53:41Z","abstract_excerpt":"Sensitivity analysis plays an important role in searching for constitutive parameters (e.g. permeability) subsurface flow simulations. The mathematics behind is to solve a dynamic constrained optimization problem. Traditional methods like finite difference and forward sensitivity analysis require computational cost that increases linearly with the number of parameters times number of cost functions. Discrete adjoint sensitivity analysis (SA) is gaining popularity due to its computational efficiency. This algorithm requires a forward run followed by a backward run who involves integrating adjoi"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1906.01132","kind":"arxiv","version":1},"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":"2026-05-17T23:44:17Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"AoAZdedHwVVrp9B0rS6/24X5tOlyGsSRA6SK7rENd2FWbEb5Lyf/2TcZezMd81PCFdZLXF82ILgg0ZL2MLp7BA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T02:27:56.600306Z"},"content_sha256":"44c77f8b9ddcf285524d7091fec9934cce17e461e2ec924ef53ca76687149029","schema_version":"1.0","event_id":"sha256:44c77f8b9ddcf285524d7091fec9934cce17e461e2ec924ef53ca76687149029"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/4DPR7YBMOFVK5DI6HIA5F2LMNC/bundle.json","state_url":"https://pith.science/pith/4DPR7YBMOFVK5DI6HIA5F2LMNC/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/4DPR7YBMOFVK5DI6HIA5F2LMNC/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":"2026-05-31T02:27:56Z","links":{"resolver":"https://pith.science/pith/4DPR7YBMOFVK5DI6HIA5F2LMNC","bundle":"https://pith.science/pith/4DPR7YBMOFVK5DI6HIA5F2LMNC/bundle.json","state":"https://pith.science/pith/4DPR7YBMOFVK5DI6HIA5F2LMNC/state.json","well_known_bundle":"https://pith.science/.well-known/pith/4DPR7YBMOFVK5DI6HIA5F2LMNC/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:4DPR7YBMOFVK5DI6HIA5F2LMNC","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":"c2a9666d586c18b353e834712694625b7d220c4da79acdb4e2ad10017272e4eb","cross_cats_sorted":["physics.geo-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.comp-ph","submitted_at":"2019-06-03T23:53:41Z","title_canon_sha256":"8e48c8e5d40ceb4a7a98333e1a53e3fb49d558f63710dcb5e65a8e625b8dc48b"},"schema_version":"1.0","source":{"id":"1906.01132","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1906.01132","created_at":"2026-05-17T23:44:17Z"},{"alias_kind":"arxiv_version","alias_value":"1906.01132v1","created_at":"2026-05-17T23:44:17Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1906.01132","created_at":"2026-05-17T23:44:17Z"},{"alias_kind":"pith_short_12","alias_value":"4DPR7YBMOFVK","created_at":"2026-05-18T12:33:10Z"},{"alias_kind":"pith_short_16","alias_value":"4DPR7YBMOFVK5DI6","created_at":"2026-05-18T12:33:10Z"},{"alias_kind":"pith_short_8","alias_value":"4DPR7YBM","created_at":"2026-05-18T12:33:10Z"}],"graph_snapshots":[{"event_id":"sha256:44c77f8b9ddcf285524d7091fec9934cce17e461e2ec924ef53ca76687149029","target":"graph","created_at":"2026-05-17T23:44:17Z","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":"Sensitivity analysis plays an important role in searching for constitutive parameters (e.g. permeability) subsurface flow simulations. The mathematics behind is to solve a dynamic constrained optimization problem. Traditional methods like finite difference and forward sensitivity analysis require computational cost that increases linearly with the number of parameters times number of cost functions. Discrete adjoint sensitivity analysis (SA) is gaining popularity due to its computational efficiency. This algorithm requires a forward run followed by a backward run who involves integrating adjoi","authors_text":"Daniel O'Malley, Satish Karra, Shu Wang","cross_cats":["physics.geo-ph"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.comp-ph","submitted_at":"2019-06-03T23:53:41Z","title":"Large-scale Inversion of Subsurface Flow Using Discrete Adjoint Method"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1906.01132","kind":"arxiv","version":1},"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":"sha256:043272e6b673d2e79923e7ce60aa0e831c58bcba440a4e7720527a0711cfe1b4","target":"record","created_at":"2026-05-17T23:44:17Z","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":"c2a9666d586c18b353e834712694625b7d220c4da79acdb4e2ad10017272e4eb","cross_cats_sorted":["physics.geo-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.comp-ph","submitted_at":"2019-06-03T23:53:41Z","title_canon_sha256":"8e48c8e5d40ceb4a7a98333e1a53e3fb49d558f63710dcb5e65a8e625b8dc48b"},"schema_version":"1.0","source":{"id":"1906.01132","kind":"arxiv","version":1}},"canonical_sha256":"e0df1fe02c716aae8d1e3a01d2e96c68a40518956c1ea6376cd55e8c5b102257","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e0df1fe02c716aae8d1e3a01d2e96c68a40518956c1ea6376cd55e8c5b102257","first_computed_at":"2026-05-17T23:44:17.751023Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:44:17.751023Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"rRqNEGa/9cAE4INUI1z3ReCtB0U0qV8V/9AoDqWAxTRhmCw0ZBturnHYpBwWlYNfc4X1gbxL0FE0VT9blOc5Bw==","signature_status":"signed_v1","signed_at":"2026-05-17T23:44:17.751679Z","signed_message":"canonical_sha256_bytes"},"source_id":"1906.01132","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:043272e6b673d2e79923e7ce60aa0e831c58bcba440a4e7720527a0711cfe1b4","sha256:44c77f8b9ddcf285524d7091fec9934cce17e461e2ec924ef53ca76687149029"],"state_sha256":"e168ffb75449d85a26dc53612c47570c42a6849eb456743d42761eb63d216e86"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"4LTRmTHfqASX4soTuklDvgRG35VD9lxCogqerZyywdPJvFkkwWGLV1cj3K4tkeYXlM2p1ZwWIk244UQAZC55Ag==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-31T02:27:56.603427Z","bundle_sha256":"3719188e7c2d2107bbaa39ede74405ab6f6ed08b3fd804a6b828e6933e332e0d"}}