{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2017:5IJSBW7ITJAFW2XMLXTHPTGL44","short_pith_number":"pith:5IJSBW7I","canonical_record":{"source":{"id":"1710.05244","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SY","submitted_at":"2017-10-14T22:44:22Z","cross_cats_sorted":[],"title_canon_sha256":"b0d2e4764a12e6b598aac9d3993df3141edefe92a3ce0dc5426e58e9b207b5cf","abstract_canon_sha256":"68dbbfa5a66b1eee4ac6cefc383754f65e990524a07288324027fabd9c3e170c"},"schema_version":"1.0"},"canonical_sha256":"ea1320dbe89a405b6aec5de677cccbe7100826b7ea3a4b513c7a57ffad42c7c1","source":{"kind":"arxiv","id":"1710.05244","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1710.05244","created_at":"2026-05-18T00:32:53Z"},{"alias_kind":"arxiv_version","alias_value":"1710.05244v1","created_at":"2026-05-18T00:32:53Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1710.05244","created_at":"2026-05-18T00:32:53Z"},{"alias_kind":"pith_short_12","alias_value":"5IJSBW7ITJAF","created_at":"2026-05-18T12:31:00Z"},{"alias_kind":"pith_short_16","alias_value":"5IJSBW7ITJAFW2XM","created_at":"2026-05-18T12:31:00Z"},{"alias_kind":"pith_short_8","alias_value":"5IJSBW7I","created_at":"2026-05-18T12:31:00Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2017:5IJSBW7ITJAFW2XMLXTHPTGL44","target":"record","payload":{"canonical_record":{"source":{"id":"1710.05244","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SY","submitted_at":"2017-10-14T22:44:22Z","cross_cats_sorted":[],"title_canon_sha256":"b0d2e4764a12e6b598aac9d3993df3141edefe92a3ce0dc5426e58e9b207b5cf","abstract_canon_sha256":"68dbbfa5a66b1eee4ac6cefc383754f65e990524a07288324027fabd9c3e170c"},"schema_version":"1.0"},"canonical_sha256":"ea1320dbe89a405b6aec5de677cccbe7100826b7ea3a4b513c7a57ffad42c7c1","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:32:53.894671Z","signature_b64":"nFFiyJJ/htcmYVxhotImLbSNLbwDuVT95y25rIcFoemEO6l+Ys0TMOy59gUj0AIFado9kSTT7uIImsdlTT97Dw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"ea1320dbe89a405b6aec5de677cccbe7100826b7ea3a4b513c7a57ffad42c7c1","last_reissued_at":"2026-05-18T00:32:53.893997Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:32:53.893997Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1710.05244","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":"2026-05-18T00:32:53Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ffGnHSCVOuCnCq9ihhxyvaWarWGKe1Eu1gAzFoDwkQ65gKZf8jyf4BDBzJlvWeH2Kiq/YG1dkdsbuo6o5dzlAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-23T17:05:11.856588Z"},"content_sha256":"e5e2fb9502c45648a9bebe804d300d2551e034490722410f08dc82ee23a343ff","schema_version":"1.0","event_id":"sha256:e5e2fb9502c45648a9bebe804d300d2551e034490722410f08dc82ee23a343ff"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2017:5IJSBW7ITJAFW2XMLXTHPTGL44","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Ensemble Kalman Filters (EnKF) for State Estimation and Prediction of Two-time Scale Nonlinear Systems with Application to Gas Turbine Engines","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.SY","authors_text":"Khashayar Khorasani, Nader Meskin, Najmeh Daroogheh","submitted_at":"2017-10-14T22:44:22Z","abstract_excerpt":"In this paper, we propose and develop a methodology for nonlinear systems health monitoring by modeling the damage and degradation mechanism dynamics as \"slow\" states that are augmented with the system \"fast\" dynamical states. This augmentation results in a two-time scale nonlinear system that is utilized for development of health estimation and prediction modules within a health monitoring framework. Towards this end, a two-time scale filtering approach is developed based on the ensemble Kalman filtering (EnKF) approach by taking advantage of the model reduction concept. The performance of ou"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1710.05244","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":"2026-05-18T00:32:53Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"EFS3yq8yXJHy5K0fL+ft+eSaRWXhtS9Ogeu7KYAcAfd8cgMXy9IApIl98J52NNZm9dwBOdjv9lfVi9SfX6iJAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-23T17:05:11.856939Z"},"content_sha256":"db771aee56eccb8e53717f3e1620968f4a95e088f17f26e3fbb61ec75717e9ec","schema_version":"1.0","event_id":"sha256:db771aee56eccb8e53717f3e1620968f4a95e088f17f26e3fbb61ec75717e9ec"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/5IJSBW7ITJAFW2XMLXTHPTGL44/bundle.json","state_url":"https://pith.science/pith/5IJSBW7ITJAFW2XMLXTHPTGL44/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/5IJSBW7ITJAFW2XMLXTHPTGL44/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":"2026-06-23T17:05:11Z","links":{"resolver":"https://pith.science/pith/5IJSBW7ITJAFW2XMLXTHPTGL44","bundle":"https://pith.science/pith/5IJSBW7ITJAFW2XMLXTHPTGL44/bundle.json","state":"https://pith.science/pith/5IJSBW7ITJAFW2XMLXTHPTGL44/state.json","well_known_bundle":"https://pith.science/.well-known/pith/5IJSBW7ITJAFW2XMLXTHPTGL44/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:5IJSBW7ITJAFW2XMLXTHPTGL44","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":"68dbbfa5a66b1eee4ac6cefc383754f65e990524a07288324027fabd9c3e170c","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SY","submitted_at":"2017-10-14T22:44:22Z","title_canon_sha256":"b0d2e4764a12e6b598aac9d3993df3141edefe92a3ce0dc5426e58e9b207b5cf"},"schema_version":"1.0","source":{"id":"1710.05244","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1710.05244","created_at":"2026-05-18T00:32:53Z"},{"alias_kind":"arxiv_version","alias_value":"1710.05244v1","created_at":"2026-05-18T00:32:53Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1710.05244","created_at":"2026-05-18T00:32:53Z"},{"alias_kind":"pith_short_12","alias_value":"5IJSBW7ITJAF","created_at":"2026-05-18T12:31:00Z"},{"alias_kind":"pith_short_16","alias_value":"5IJSBW7ITJAFW2XM","created_at":"2026-05-18T12:31:00Z"},{"alias_kind":"pith_short_8","alias_value":"5IJSBW7I","created_at":"2026-05-18T12:31:00Z"}],"graph_snapshots":[{"event_id":"sha256:db771aee56eccb8e53717f3e1620968f4a95e088f17f26e3fbb61ec75717e9ec","target":"graph","created_at":"2026-05-18T00:32:53Z","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":"In this paper, we propose and develop a methodology for nonlinear systems health monitoring by modeling the damage and degradation mechanism dynamics as \"slow\" states that are augmented with the system \"fast\" dynamical states. This augmentation results in a two-time scale nonlinear system that is utilized for development of health estimation and prediction modules within a health monitoring framework. Towards this end, a two-time scale filtering approach is developed based on the ensemble Kalman filtering (EnKF) approach by taking advantage of the model reduction concept. The performance of ou","authors_text":"Khashayar Khorasani, Nader Meskin, Najmeh Daroogheh","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SY","submitted_at":"2017-10-14T22:44:22Z","title":"Ensemble Kalman Filters (EnKF) for State Estimation and Prediction of Two-time Scale Nonlinear Systems with Application to Gas Turbine Engines"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1710.05244","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:e5e2fb9502c45648a9bebe804d300d2551e034490722410f08dc82ee23a343ff","target":"record","created_at":"2026-05-18T00:32:53Z","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":"68dbbfa5a66b1eee4ac6cefc383754f65e990524a07288324027fabd9c3e170c","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SY","submitted_at":"2017-10-14T22:44:22Z","title_canon_sha256":"b0d2e4764a12e6b598aac9d3993df3141edefe92a3ce0dc5426e58e9b207b5cf"},"schema_version":"1.0","source":{"id":"1710.05244","kind":"arxiv","version":1}},"canonical_sha256":"ea1320dbe89a405b6aec5de677cccbe7100826b7ea3a4b513c7a57ffad42c7c1","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"ea1320dbe89a405b6aec5de677cccbe7100826b7ea3a4b513c7a57ffad42c7c1","first_computed_at":"2026-05-18T00:32:53.893997Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:32:53.893997Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"nFFiyJJ/htcmYVxhotImLbSNLbwDuVT95y25rIcFoemEO6l+Ys0TMOy59gUj0AIFado9kSTT7uIImsdlTT97Dw==","signature_status":"signed_v1","signed_at":"2026-05-18T00:32:53.894671Z","signed_message":"canonical_sha256_bytes"},"source_id":"1710.05244","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:e5e2fb9502c45648a9bebe804d300d2551e034490722410f08dc82ee23a343ff","sha256:db771aee56eccb8e53717f3e1620968f4a95e088f17f26e3fbb61ec75717e9ec"],"state_sha256":"a89a59610bd466eca496f98bb082501b7649a83afc98494743f063d8fd7c07a5"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"JLtTKMA/tjRFCrr2l8OYo+wwANVC+0yr+ZdX5Bx+wlmCxqSKoLcTc0pl/IwfTo8NPD11L7UOmQZRQaFZrZaFAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-23T17:05:11.858949Z","bundle_sha256":"c232514f87c4199cd24152ed7b36633d4e24d790443fe2488b831825fffb4a7d"}}