{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:ZLAWFSXBA3B4W7EC43EU53Z5KN","short_pith_number":"pith:ZLAWFSXB","canonical_record":{"source":{"id":"1803.01805","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.NA","submitted_at":"2018-03-05T17:59:15Z","cross_cats_sorted":[],"title_canon_sha256":"0b00edf2d6476acba6fe3efc3776ef0d6675411027fad814babeae387fa3fce8","abstract_canon_sha256":"4d249528c3d0e327955d7d62f496d6049568864112611e315459821722064a5b"},"schema_version":"1.0"},"canonical_sha256":"cac162cae106c3cb7c82e6c94eef3d537f19518a6284a15e2f048ce376acc763","source":{"kind":"arxiv","id":"1803.01805","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1803.01805","created_at":"2026-05-18T00:21:59Z"},{"alias_kind":"arxiv_version","alias_value":"1803.01805v1","created_at":"2026-05-18T00:21:59Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1803.01805","created_at":"2026-05-18T00:21:59Z"},{"alias_kind":"pith_short_12","alias_value":"ZLAWFSXBA3B4","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_16","alias_value":"ZLAWFSXBA3B4W7EC","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_8","alias_value":"ZLAWFSXB","created_at":"2026-05-18T12:33:07Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:ZLAWFSXBA3B4W7EC43EU53Z5KN","target":"record","payload":{"canonical_record":{"source":{"id":"1803.01805","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.NA","submitted_at":"2018-03-05T17:59:15Z","cross_cats_sorted":[],"title_canon_sha256":"0b00edf2d6476acba6fe3efc3776ef0d6675411027fad814babeae387fa3fce8","abstract_canon_sha256":"4d249528c3d0e327955d7d62f496d6049568864112611e315459821722064a5b"},"schema_version":"1.0"},"canonical_sha256":"cac162cae106c3cb7c82e6c94eef3d537f19518a6284a15e2f048ce376acc763","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:21:59.570132Z","signature_b64":"igeEB/TTtQPLSWI0KKcScCiMjEZtwPDcom4h67a0Eho44UuY1KJNvWuik1TkoSeA7LyYwHg+2ROZExY0qvtMBA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"cac162cae106c3cb7c82e6c94eef3d537f19518a6284a15e2f048ce376acc763","last_reissued_at":"2026-05-18T00:21:59.569291Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:21:59.569291Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1803.01805","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":"2026-05-18T00:21:59Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"OrMTBOelvCKmqufjI3YwyfXQyDsUpraW/WGNkZtp3t5zX0HXCltuaqUpAqEwQQchUl1eqIlcANu6zgmldB0HBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-21T20:11:03.244644Z"},"content_sha256":"2ea78b44a257b89d62d631e3ac06ea0a86e44463549d1e8776bba7f8a504d172","schema_version":"1.0","event_id":"sha256:2ea78b44a257b89d62d631e3ac06ea0a86e44463549d1e8776bba7f8a504d172"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:ZLAWFSXBA3B4W7EC43EU53Z5KN","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Model Reduction for a Pulsed Detonation Combuster via Shifted Proper Orthogonal Decomposition","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"math.NA","authors_text":"Julius Reiss, Philipp Schulze, Volker Mehrmann","submitted_at":"2018-03-05T17:59:15Z","abstract_excerpt":"We propose a new algorithm to compute a shifted proper orthogonal decomposition (sPOD) for systems dominated by multiple transport velocities. The sPOD is a recently proposed mode decomposition technique which overcomes the poor performance of classical methods like the proper orthogonal decomposition (POD) for transport-dominated phenomena. This is achieved by identifying the transport directions and velocities and by shifting the modes in space to track the transports. Our new algorithm carries out a residual minimization in which the main computational cost arises from solving a nonlinear o"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1803.01805","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":"2026-05-18T00:21:59Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ehOSiH6mLvbUpVTwUZh4XNNS6B+I17m9wk4AcE4GGlyXCQEq0fpI4Tm+uVzAF6Hag43dkqjVAOhdpDn6NSuqCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-21T20:11:03.244987Z"},"content_sha256":"e2e91c7bc5cf664b18a150ae0631092b56cd4ad56b364645008735e31121ba93","schema_version":"1.0","event_id":"sha256:e2e91c7bc5cf664b18a150ae0631092b56cd4ad56b364645008735e31121ba93"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/ZLAWFSXBA3B4W7EC43EU53Z5KN/bundle.json","state_url":"https://pith.science/pith/ZLAWFSXBA3B4W7EC43EU53Z5KN/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/ZLAWFSXBA3B4W7EC43EU53Z5KN/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":"2026-06-21T20:11:03Z","links":{"resolver":"https://pith.science/pith/ZLAWFSXBA3B4W7EC43EU53Z5KN","bundle":"https://pith.science/pith/ZLAWFSXBA3B4W7EC43EU53Z5KN/bundle.json","state":"https://pith.science/pith/ZLAWFSXBA3B4W7EC43EU53Z5KN/state.json","well_known_bundle":"https://pith.science/.well-known/pith/ZLAWFSXBA3B4W7EC43EU53Z5KN/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:ZLAWFSXBA3B4W7EC43EU53Z5KN","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":"4d249528c3d0e327955d7d62f496d6049568864112611e315459821722064a5b","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.NA","submitted_at":"2018-03-05T17:59:15Z","title_canon_sha256":"0b00edf2d6476acba6fe3efc3776ef0d6675411027fad814babeae387fa3fce8"},"schema_version":"1.0","source":{"id":"1803.01805","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1803.01805","created_at":"2026-05-18T00:21:59Z"},{"alias_kind":"arxiv_version","alias_value":"1803.01805v1","created_at":"2026-05-18T00:21:59Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1803.01805","created_at":"2026-05-18T00:21:59Z"},{"alias_kind":"pith_short_12","alias_value":"ZLAWFSXBA3B4","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_16","alias_value":"ZLAWFSXBA3B4W7EC","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_8","alias_value":"ZLAWFSXB","created_at":"2026-05-18T12:33:07Z"}],"graph_snapshots":[{"event_id":"sha256:e2e91c7bc5cf664b18a150ae0631092b56cd4ad56b364645008735e31121ba93","target":"graph","created_at":"2026-05-18T00:21:59Z","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":"We propose a new algorithm to compute a shifted proper orthogonal decomposition (sPOD) for systems dominated by multiple transport velocities. The sPOD is a recently proposed mode decomposition technique which overcomes the poor performance of classical methods like the proper orthogonal decomposition (POD) for transport-dominated phenomena. This is achieved by identifying the transport directions and velocities and by shifting the modes in space to track the transports. Our new algorithm carries out a residual minimization in which the main computational cost arises from solving a nonlinear o","authors_text":"Julius Reiss, Philipp Schulze, Volker Mehrmann","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.NA","submitted_at":"2018-03-05T17:59:15Z","title":"Model Reduction for a Pulsed Detonation Combuster via Shifted Proper Orthogonal Decomposition"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1803.01805","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":"sha256:2ea78b44a257b89d62d631e3ac06ea0a86e44463549d1e8776bba7f8a504d172","target":"record","created_at":"2026-05-18T00:21:59Z","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":"4d249528c3d0e327955d7d62f496d6049568864112611e315459821722064a5b","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"math.NA","submitted_at":"2018-03-05T17:59:15Z","title_canon_sha256":"0b00edf2d6476acba6fe3efc3776ef0d6675411027fad814babeae387fa3fce8"},"schema_version":"1.0","source":{"id":"1803.01805","kind":"arxiv","version":1}},"canonical_sha256":"cac162cae106c3cb7c82e6c94eef3d537f19518a6284a15e2f048ce376acc763","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"cac162cae106c3cb7c82e6c94eef3d537f19518a6284a15e2f048ce376acc763","first_computed_at":"2026-05-18T00:21:59.569291Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:21:59.569291Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"igeEB/TTtQPLSWI0KKcScCiMjEZtwPDcom4h67a0Eho44UuY1KJNvWuik1TkoSeA7LyYwHg+2ROZExY0qvtMBA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:21:59.570132Z","signed_message":"canonical_sha256_bytes"},"source_id":"1803.01805","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:2ea78b44a257b89d62d631e3ac06ea0a86e44463549d1e8776bba7f8a504d172","sha256:e2e91c7bc5cf664b18a150ae0631092b56cd4ad56b364645008735e31121ba93"],"state_sha256":"4d52b3229bfdca8faa4136943dad1aa84cc241f02880b362046b87c8dbb49444"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"cEwtGH5bljW5VTe2Rl1a2pfISahJrcLlq1g4+xpOK5I7iQyVvOGwP5m1haTqOrPyMbX9l9WnaW9JgZSdxYrkBQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-21T20:11:03.246908Z","bundle_sha256":"384a3425e465a7a6e07a85c2928a92475a0ba8b16f0b51d7d2a8deaa18bb1f37"}}