{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:P7KY276LGHJJVKWW4OXDCWGOMR","short_pith_number":"pith:P7KY276L","canonical_record":{"source":{"id":"1903.08912","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2019-03-21T10:30:47Z","cross_cats_sorted":["eess.SP","stat.ML"],"title_canon_sha256":"f953a714849933ab71dd34ee3ec07a50b7f335598a4945602d1b2643a2d1fa74","abstract_canon_sha256":"ab221eff012c0c230aee561fb6e2feedea9ba8aac2010b76f01a8d1f1b683ee0"},"schema_version":"1.0"},"canonical_sha256":"7fd58d7fcb31d29aaad6e3ae3158ce6440460a5bdd7e04290eb9c89851076eb1","source":{"kind":"arxiv","id":"1903.08912","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1903.08912","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"arxiv_version","alias_value":"1903.08912v1","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1903.08912","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"pith_short_12","alias_value":"P7KY276LGHJJ","created_at":"2026-05-18T12:33:24Z"},{"alias_kind":"pith_short_16","alias_value":"P7KY276LGHJJVKWW","created_at":"2026-05-18T12:33:24Z"},{"alias_kind":"pith_short_8","alias_value":"P7KY276L","created_at":"2026-05-18T12:33:24Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:P7KY276LGHJJVKWW4OXDCWGOMR","target":"record","payload":{"canonical_record":{"source":{"id":"1903.08912","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2019-03-21T10:30:47Z","cross_cats_sorted":["eess.SP","stat.ML"],"title_canon_sha256":"f953a714849933ab71dd34ee3ec07a50b7f335598a4945602d1b2643a2d1fa74","abstract_canon_sha256":"ab221eff012c0c230aee561fb6e2feedea9ba8aac2010b76f01a8d1f1b683ee0"},"schema_version":"1.0"},"canonical_sha256":"7fd58d7fcb31d29aaad6e3ae3158ce6440460a5bdd7e04290eb9c89851076eb1","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:50:43.596121Z","signature_b64":"gWU5vExKv2O1yz8DcbW23KVDdGVbB3UhfDaY7d3Xd5YJBOWWQTSZ6NNECJboFldD2cWHwxjx9hDown2mIZJtBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"7fd58d7fcb31d29aaad6e3ae3158ce6440460a5bdd7e04290eb9c89851076eb1","last_reissued_at":"2026-05-17T23:50:43.595729Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:50:43.595729Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1903.08912","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":"2026-05-17T23:50:43Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"wxO9NlIxj2Uf7UlrycpnpZ9mlfkB4/cdi5Gz4YVvHYuZwOtDdCMg/RTExAq3bm5grJpbiBA105WjjHDxJ46MAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T08:50:49.835936Z"},"content_sha256":"51ef83ad0f0dbd85af87aa00361f7d9aaefc84d88d189566ca8de26a547e6dde","schema_version":"1.0","event_id":"sha256:51ef83ad0f0dbd85af87aa00361f7d9aaefc84d88d189566ca8de26a547e6dde"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:P7KY276LGHJJVKWW4OXDCWGOMR","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"PPGnet: Deep Network for Device Independent Heart Rate Estimation from Photoplethysmogram","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["eess.SP","stat.ML"],"primary_cat":"cs.LG","authors_text":"Jayaraj Joseph, Mohanasankar Sivaprakasam, Preejith S.P, Shyam A, Vignesh Ravichandran","submitted_at":"2019-03-21T10:30:47Z","abstract_excerpt":"Photoplethysmogram (PPG) is increasingly used to provide monitoring of the cardiovascular system under ambulatory conditions. Wearable devices like smartwatches use PPG to allow long term unobtrusive monitoring of heart rate in free living conditions. PPG based heart rate measurement is unfortunately highly susceptible to motion artifacts, particularly when measured from the wrist. Traditional machine learning and deep learning approaches rely on tri-axial accelerometer data along with PPG to perform heart rate estimation. The conventional learning based approaches have not addressed the need "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1903.08912","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":"2026-05-17T23:50:43Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"qx+c8XLyBMEXKLnJdKrkRfE1cf9eMNBMBPYqL/ebUutZ9dDd2K0d0GWo0i4qwsP4fNJbfj8BnU++juBntCIgBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T08:50:49.836284Z"},"content_sha256":"429da3dbc965db06328116aa912d4eb8a8b84e8a2192d583c6bd8f9d88d79887","schema_version":"1.0","event_id":"sha256:429da3dbc965db06328116aa912d4eb8a8b84e8a2192d583c6bd8f9d88d79887"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/P7KY276LGHJJVKWW4OXDCWGOMR/bundle.json","state_url":"https://pith.science/pith/P7KY276LGHJJVKWW4OXDCWGOMR/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/P7KY276LGHJJVKWW4OXDCWGOMR/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":"2026-05-28T08:50:49Z","links":{"resolver":"https://pith.science/pith/P7KY276LGHJJVKWW4OXDCWGOMR","bundle":"https://pith.science/pith/P7KY276LGHJJVKWW4OXDCWGOMR/bundle.json","state":"https://pith.science/pith/P7KY276LGHJJVKWW4OXDCWGOMR/state.json","well_known_bundle":"https://pith.science/.well-known/pith/P7KY276LGHJJVKWW4OXDCWGOMR/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:P7KY276LGHJJVKWW4OXDCWGOMR","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":"ab221eff012c0c230aee561fb6e2feedea9ba8aac2010b76f01a8d1f1b683ee0","cross_cats_sorted":["eess.SP","stat.ML"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2019-03-21T10:30:47Z","title_canon_sha256":"f953a714849933ab71dd34ee3ec07a50b7f335598a4945602d1b2643a2d1fa74"},"schema_version":"1.0","source":{"id":"1903.08912","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1903.08912","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"arxiv_version","alias_value":"1903.08912v1","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1903.08912","created_at":"2026-05-17T23:50:43Z"},{"alias_kind":"pith_short_12","alias_value":"P7KY276LGHJJ","created_at":"2026-05-18T12:33:24Z"},{"alias_kind":"pith_short_16","alias_value":"P7KY276LGHJJVKWW","created_at":"2026-05-18T12:33:24Z"},{"alias_kind":"pith_short_8","alias_value":"P7KY276L","created_at":"2026-05-18T12:33:24Z"}],"graph_snapshots":[{"event_id":"sha256:429da3dbc965db06328116aa912d4eb8a8b84e8a2192d583c6bd8f9d88d79887","target":"graph","created_at":"2026-05-17T23:50:43Z","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":"Photoplethysmogram (PPG) is increasingly used to provide monitoring of the cardiovascular system under ambulatory conditions. Wearable devices like smartwatches use PPG to allow long term unobtrusive monitoring of heart rate in free living conditions. PPG based heart rate measurement is unfortunately highly susceptible to motion artifacts, particularly when measured from the wrist. Traditional machine learning and deep learning approaches rely on tri-axial accelerometer data along with PPG to perform heart rate estimation. The conventional learning based approaches have not addressed the need ","authors_text":"Jayaraj Joseph, Mohanasankar Sivaprakasam, Preejith S.P, Shyam A, Vignesh Ravichandran","cross_cats":["eess.SP","stat.ML"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2019-03-21T10:30:47Z","title":"PPGnet: Deep Network for Device Independent Heart Rate Estimation from Photoplethysmogram"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1903.08912","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":"sha256:51ef83ad0f0dbd85af87aa00361f7d9aaefc84d88d189566ca8de26a547e6dde","target":"record","created_at":"2026-05-17T23:50:43Z","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":"ab221eff012c0c230aee561fb6e2feedea9ba8aac2010b76f01a8d1f1b683ee0","cross_cats_sorted":["eess.SP","stat.ML"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.LG","submitted_at":"2019-03-21T10:30:47Z","title_canon_sha256":"f953a714849933ab71dd34ee3ec07a50b7f335598a4945602d1b2643a2d1fa74"},"schema_version":"1.0","source":{"id":"1903.08912","kind":"arxiv","version":1}},"canonical_sha256":"7fd58d7fcb31d29aaad6e3ae3158ce6440460a5bdd7e04290eb9c89851076eb1","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"7fd58d7fcb31d29aaad6e3ae3158ce6440460a5bdd7e04290eb9c89851076eb1","first_computed_at":"2026-05-17T23:50:43.595729Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:50:43.595729Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"gWU5vExKv2O1yz8DcbW23KVDdGVbB3UhfDaY7d3Xd5YJBOWWQTSZ6NNECJboFldD2cWHwxjx9hDown2mIZJtBg==","signature_status":"signed_v1","signed_at":"2026-05-17T23:50:43.596121Z","signed_message":"canonical_sha256_bytes"},"source_id":"1903.08912","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:51ef83ad0f0dbd85af87aa00361f7d9aaefc84d88d189566ca8de26a547e6dde","sha256:429da3dbc965db06328116aa912d4eb8a8b84e8a2192d583c6bd8f9d88d79887"],"state_sha256":"266d33328cd6348386fd3ae369e9725f56e28a201f2c6b347002c538c39d33da"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"w0CVidnVxYmxLXqFPBPDmbdl/FhI5pnh8AMFlrKxXc/33gUALqgMl4NLTGrE/ScknFDuOkFHOXgaXpqQYMG6DQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-28T08:50:49.838404Z","bundle_sha256":"c430fcac2e9703c3f4ca988f47f6dcd69e0ebd466e88d392dc2e809b821fef51"}}