{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:NJLOOWJDHBRLNJIEHQ55LLVGC3","short_pith_number":"pith:NJLOOWJD","canonical_record":{"source":{"id":"1802.00775","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-02-02T17:19:03Z","cross_cats_sorted":[],"title_canon_sha256":"03d54c0092141a0e683c06cf841206e394ae391e5378e83cc16750990e97a9d0","abstract_canon_sha256":"aabed44b3e98140c7fb5f6ed5823e95354dc2afdb5233701ec8894893806d709"},"schema_version":"1.0"},"canonical_sha256":"6a56e759233862b6a5043c3bd5aea616ca756d74afc5575808fa81d62e106cea","source":{"kind":"arxiv","id":"1802.00775","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1802.00775","created_at":"2026-05-17T23:56:58Z"},{"alias_kind":"arxiv_version","alias_value":"1802.00775v1","created_at":"2026-05-17T23:56:58Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1802.00775","created_at":"2026-05-17T23:56:58Z"},{"alias_kind":"pith_short_12","alias_value":"NJLOOWJDHBRL","created_at":"2026-05-18T12:32:40Z"},{"alias_kind":"pith_short_16","alias_value":"NJLOOWJDHBRLNJIE","created_at":"2026-05-18T12:32:40Z"},{"alias_kind":"pith_short_8","alias_value":"NJLOOWJD","created_at":"2026-05-18T12:32:40Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:NJLOOWJDHBRLNJIEHQ55LLVGC3","target":"record","payload":{"canonical_record":{"source":{"id":"1802.00775","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-02-02T17:19:03Z","cross_cats_sorted":[],"title_canon_sha256":"03d54c0092141a0e683c06cf841206e394ae391e5378e83cc16750990e97a9d0","abstract_canon_sha256":"aabed44b3e98140c7fb5f6ed5823e95354dc2afdb5233701ec8894893806d709"},"schema_version":"1.0"},"canonical_sha256":"6a56e759233862b6a5043c3bd5aea616ca756d74afc5575808fa81d62e106cea","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:56:58.695305Z","signature_b64":"a5yDnpBwbT3ixauLpFCzJq6hShCRVLO8DVL3lQXkGxMqqvzGZeR9tq7r+Om3U2GY526BC0LNF0aAi7VCDWrwDg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"6a56e759233862b6a5043c3bd5aea616ca756d74afc5575808fa81d62e106cea","last_reissued_at":"2026-05-17T23:56:58.694546Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:56:58.694546Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1802.00775","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":"2026-05-17T23:56:58Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"SwaShwJhhQbHG/9+zxGe6vw9lxdqkwWuVoIGggxU3vupu2/MZxQANfp1+Y8aZz5bIAh7ImvUEOEHBTF8bUnNAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T13:16:49.231218Z"},"content_sha256":"8f6b7e2852b1f79dc2487a5de97d45e70fb3664fa473785d7a4cdc9618ab9261","schema_version":"1.0","event_id":"sha256:8f6b7e2852b1f79dc2487a5de97d45e70fb3664fa473785d7a4cdc9618ab9261"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:NJLOOWJDHBRLNJIEHQ55LLVGC3","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Data-Driven, Physics-Based Feature Extraction from Fluid Flow Fields","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"physics.flu-dyn","authors_text":"Carlos Michel\\'en Str\\\"ofer, Eric Paterson, Heng Xiao, Jinlong Wu","submitted_at":"2018-02-02T17:19:03Z","abstract_excerpt":"Feature identification is an important task in many fluid dynamics applications and diverse methods have been developed for this purpose. These methods are based on a physical understanding of the underlying behavior of the flow in the vicinity of the feature. Particularly, they rely on definition of suitable criteria (i.e. point-based or neighborhood-based derived properties) and proper selection of thresholds. For instance, among other techniques, vortex identification can be done through computing the Q-criterion or by considering the center of looping streamlines. However, these methods re"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1802.00775","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":"2026-05-17T23:56:58Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"T5N18dv/bAJ35WwUhsX/S7smf+2Xf/azpcHJnhywkOJBeo7Ht8TuOiykVkYGBBQhub0FxIWXgK0vu78QCxNDBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T13:16:49.231930Z"},"content_sha256":"e980dd4d21abf1e6eff41edb4a5ade86a95c757bc001a202b338fd0e658281fa","schema_version":"1.0","event_id":"sha256:e980dd4d21abf1e6eff41edb4a5ade86a95c757bc001a202b338fd0e658281fa"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/NJLOOWJDHBRLNJIEHQ55LLVGC3/bundle.json","state_url":"https://pith.science/pith/NJLOOWJDHBRLNJIEHQ55LLVGC3/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/NJLOOWJDHBRLNJIEHQ55LLVGC3/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":"2026-06-07T13:16:49Z","links":{"resolver":"https://pith.science/pith/NJLOOWJDHBRLNJIEHQ55LLVGC3","bundle":"https://pith.science/pith/NJLOOWJDHBRLNJIEHQ55LLVGC3/bundle.json","state":"https://pith.science/pith/NJLOOWJDHBRLNJIEHQ55LLVGC3/state.json","well_known_bundle":"https://pith.science/.well-known/pith/NJLOOWJDHBRLNJIEHQ55LLVGC3/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:NJLOOWJDHBRLNJIEHQ55LLVGC3","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":"aabed44b3e98140c7fb5f6ed5823e95354dc2afdb5233701ec8894893806d709","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-02-02T17:19:03Z","title_canon_sha256":"03d54c0092141a0e683c06cf841206e394ae391e5378e83cc16750990e97a9d0"},"schema_version":"1.0","source":{"id":"1802.00775","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1802.00775","created_at":"2026-05-17T23:56:58Z"},{"alias_kind":"arxiv_version","alias_value":"1802.00775v1","created_at":"2026-05-17T23:56:58Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1802.00775","created_at":"2026-05-17T23:56:58Z"},{"alias_kind":"pith_short_12","alias_value":"NJLOOWJDHBRL","created_at":"2026-05-18T12:32:40Z"},{"alias_kind":"pith_short_16","alias_value":"NJLOOWJDHBRLNJIE","created_at":"2026-05-18T12:32:40Z"},{"alias_kind":"pith_short_8","alias_value":"NJLOOWJD","created_at":"2026-05-18T12:32:40Z"}],"graph_snapshots":[{"event_id":"sha256:e980dd4d21abf1e6eff41edb4a5ade86a95c757bc001a202b338fd0e658281fa","target":"graph","created_at":"2026-05-17T23:56:58Z","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":"Feature identification is an important task in many fluid dynamics applications and diverse methods have been developed for this purpose. These methods are based on a physical understanding of the underlying behavior of the flow in the vicinity of the feature. Particularly, they rely on definition of suitable criteria (i.e. point-based or neighborhood-based derived properties) and proper selection of thresholds. For instance, among other techniques, vortex identification can be done through computing the Q-criterion or by considering the center of looping streamlines. However, these methods re","authors_text":"Carlos Michel\\'en Str\\\"ofer, Eric Paterson, Heng Xiao, Jinlong Wu","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-02-02T17:19:03Z","title":"Data-Driven, Physics-Based Feature Extraction from Fluid Flow Fields"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1802.00775","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":"sha256:8f6b7e2852b1f79dc2487a5de97d45e70fb3664fa473785d7a4cdc9618ab9261","target":"record","created_at":"2026-05-17T23:56:58Z","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":"aabed44b3e98140c7fb5f6ed5823e95354dc2afdb5233701ec8894893806d709","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.flu-dyn","submitted_at":"2018-02-02T17:19:03Z","title_canon_sha256":"03d54c0092141a0e683c06cf841206e394ae391e5378e83cc16750990e97a9d0"},"schema_version":"1.0","source":{"id":"1802.00775","kind":"arxiv","version":1}},"canonical_sha256":"6a56e759233862b6a5043c3bd5aea616ca756d74afc5575808fa81d62e106cea","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"6a56e759233862b6a5043c3bd5aea616ca756d74afc5575808fa81d62e106cea","first_computed_at":"2026-05-17T23:56:58.694546Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:56:58.694546Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"a5yDnpBwbT3ixauLpFCzJq6hShCRVLO8DVL3lQXkGxMqqvzGZeR9tq7r+Om3U2GY526BC0LNF0aAi7VCDWrwDg==","signature_status":"signed_v1","signed_at":"2026-05-17T23:56:58.695305Z","signed_message":"canonical_sha256_bytes"},"source_id":"1802.00775","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:8f6b7e2852b1f79dc2487a5de97d45e70fb3664fa473785d7a4cdc9618ab9261","sha256:e980dd4d21abf1e6eff41edb4a5ade86a95c757bc001a202b338fd0e658281fa"],"state_sha256":"0a38ff54c0777e2fd579060395d0f6b6b3df26daf4c2747d68e248dfd14312fa"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"8AXu/EoNh5dMXeAK2mSgqoYc3b0bKBkYSAwQ5PNOJocbWibIfxzeknlQjtUt0T4YvgFmoe5664TYRVj9jClUCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-07T13:16:49.235702Z","bundle_sha256":"ce3cf24ec194e13efdd063131468354200768946e2137635369312aac275ab5e"}}