{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2014:F7POWREQL6RW2CIDTCEELCNRRH","short_pith_number":"pith:F7POWREQ","canonical_record":{"source":{"id":"1403.5081","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.FL","submitted_at":"2014-03-20T09:41:33Z","cross_cats_sorted":[],"title_canon_sha256":"8f8d82fb8b9823b1438c35588030e5e15a29104fe060fc8b577545bbf758476c","abstract_canon_sha256":"17b896db7a5f2c5e5c2fa4d77e2d76726f0a0f37eab5f8734a5f788eed981a99"},"schema_version":"1.0"},"canonical_sha256":"2fdeeb44905fa36d090398884589b189ebeaf9410a563e7ac3d632a140a2468b","source":{"kind":"arxiv","id":"1403.5081","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1403.5081","created_at":"2026-05-18T02:55:56Z"},{"alias_kind":"arxiv_version","alias_value":"1403.5081v2","created_at":"2026-05-18T02:55:56Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1403.5081","created_at":"2026-05-18T02:55:56Z"},{"alias_kind":"pith_short_12","alias_value":"F7POWREQL6RW","created_at":"2026-05-18T12:28:28Z"},{"alias_kind":"pith_short_16","alias_value":"F7POWREQL6RW2CID","created_at":"2026-05-18T12:28:28Z"},{"alias_kind":"pith_short_8","alias_value":"F7POWREQ","created_at":"2026-05-18T12:28:28Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2014:F7POWREQL6RW2CIDTCEELCNRRH","target":"record","payload":{"canonical_record":{"source":{"id":"1403.5081","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.FL","submitted_at":"2014-03-20T09:41:33Z","cross_cats_sorted":[],"title_canon_sha256":"8f8d82fb8b9823b1438c35588030e5e15a29104fe060fc8b577545bbf758476c","abstract_canon_sha256":"17b896db7a5f2c5e5c2fa4d77e2d76726f0a0f37eab5f8734a5f788eed981a99"},"schema_version":"1.0"},"canonical_sha256":"2fdeeb44905fa36d090398884589b189ebeaf9410a563e7ac3d632a140a2468b","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:55:56.826906Z","signature_b64":"YqpLkQ7jbc/JmvoIfSroqXtTOozLcV0PRViQGPifo36xBgrUtVz4AuHjJANsDQghykn8TGf27pvzE3SFbLaVDg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"2fdeeb44905fa36d090398884589b189ebeaf9410a563e7ac3d632a140a2468b","last_reissued_at":"2026-05-18T02:55:56.826289Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:55:56.826289Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1403.5081","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T02:55:56Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ejZ/0Zub4PsxOtPzsawtvYaCY4XdV0x4kobIQi1Ts7qHzp221SeUsioPmnZudr1i59nmop5PthKMlsyO+8KpAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-27T02:32:10.038386Z"},"content_sha256":"1450eff10f4932dcd92bbabc741058fc485f29de131435c17f6ecb0713b49468","schema_version":"1.0","event_id":"sha256:1450eff10f4932dcd92bbabc741058fc485f29de131435c17f6ecb0713b49468"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2014:F7POWREQL6RW2CIDTCEELCNRRH","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Enforcing Operational Properties including Blockfreeness for Deterministic Pushdown Automata","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"cs.FL","authors_text":"Sven Schneider, Uwe Nestmann","submitted_at":"2014-03-20T09:41:33Z","abstract_excerpt":"We present an algorithm which modifies a deterministic pushdown automaton (DPDA) such that (i) the marked language is preserved, (ii) lifelocks are removed, (iii) deadlocks are removed, (iv) all states and edges are accessible, and (v) operational blockfreeness is established (i.e., coaccessibility in the sense that every initial derivation can be continued to a marking configuration). This problem can be trivially solved for deterministic finite automata (DFA) but is not solvable for standard petri net classes. The algorithm is required for an operational extension of the supervisory control "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1403.5081","kind":"arxiv","version":2},"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":"2026-05-18T02:55:56Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"GQ38WWfTYw++tWJo4cyABJbHSbByMS2bePLoYGktLMjNn3opIeFJfX7Wtbu/pVEMoou8Ixce4h7nb1CvrlfxCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-27T02:32:10.038735Z"},"content_sha256":"41259d0f083423a6236bcf6b90acee2297940077f0bbb2c62a89e1b5ef44e89c","schema_version":"1.0","event_id":"sha256:41259d0f083423a6236bcf6b90acee2297940077f0bbb2c62a89e1b5ef44e89c"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/F7POWREQL6RW2CIDTCEELCNRRH/bundle.json","state_url":"https://pith.science/pith/F7POWREQL6RW2CIDTCEELCNRRH/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/F7POWREQL6RW2CIDTCEELCNRRH/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":"2026-06-27T02:32:10Z","links":{"resolver":"https://pith.science/pith/F7POWREQL6RW2CIDTCEELCNRRH","bundle":"https://pith.science/pith/F7POWREQL6RW2CIDTCEELCNRRH/bundle.json","state":"https://pith.science/pith/F7POWREQL6RW2CIDTCEELCNRRH/state.json","well_known_bundle":"https://pith.science/.well-known/pith/F7POWREQL6RW2CIDTCEELCNRRH/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2014:F7POWREQL6RW2CIDTCEELCNRRH","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":"17b896db7a5f2c5e5c2fa4d77e2d76726f0a0f37eab5f8734a5f788eed981a99","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.FL","submitted_at":"2014-03-20T09:41:33Z","title_canon_sha256":"8f8d82fb8b9823b1438c35588030e5e15a29104fe060fc8b577545bbf758476c"},"schema_version":"1.0","source":{"id":"1403.5081","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1403.5081","created_at":"2026-05-18T02:55:56Z"},{"alias_kind":"arxiv_version","alias_value":"1403.5081v2","created_at":"2026-05-18T02:55:56Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1403.5081","created_at":"2026-05-18T02:55:56Z"},{"alias_kind":"pith_short_12","alias_value":"F7POWREQL6RW","created_at":"2026-05-18T12:28:28Z"},{"alias_kind":"pith_short_16","alias_value":"F7POWREQL6RW2CID","created_at":"2026-05-18T12:28:28Z"},{"alias_kind":"pith_short_8","alias_value":"F7POWREQ","created_at":"2026-05-18T12:28:28Z"}],"graph_snapshots":[{"event_id":"sha256:41259d0f083423a6236bcf6b90acee2297940077f0bbb2c62a89e1b5ef44e89c","target":"graph","created_at":"2026-05-18T02:55:56Z","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 present an algorithm which modifies a deterministic pushdown automaton (DPDA) such that (i) the marked language is preserved, (ii) lifelocks are removed, (iii) deadlocks are removed, (iv) all states and edges are accessible, and (v) operational blockfreeness is established (i.e., coaccessibility in the sense that every initial derivation can be continued to a marking configuration). This problem can be trivially solved for deterministic finite automata (DFA) but is not solvable for standard petri net classes. The algorithm is required for an operational extension of the supervisory control ","authors_text":"Sven Schneider, Uwe Nestmann","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.FL","submitted_at":"2014-03-20T09:41:33Z","title":"Enforcing Operational Properties including Blockfreeness for Deterministic Pushdown Automata"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1403.5081","kind":"arxiv","version":2},"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":"sha256:1450eff10f4932dcd92bbabc741058fc485f29de131435c17f6ecb0713b49468","target":"record","created_at":"2026-05-18T02:55:56Z","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":"17b896db7a5f2c5e5c2fa4d77e2d76726f0a0f37eab5f8734a5f788eed981a99","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.FL","submitted_at":"2014-03-20T09:41:33Z","title_canon_sha256":"8f8d82fb8b9823b1438c35588030e5e15a29104fe060fc8b577545bbf758476c"},"schema_version":"1.0","source":{"id":"1403.5081","kind":"arxiv","version":2}},"canonical_sha256":"2fdeeb44905fa36d090398884589b189ebeaf9410a563e7ac3d632a140a2468b","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"2fdeeb44905fa36d090398884589b189ebeaf9410a563e7ac3d632a140a2468b","first_computed_at":"2026-05-18T02:55:56.826289Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:55:56.826289Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"YqpLkQ7jbc/JmvoIfSroqXtTOozLcV0PRViQGPifo36xBgrUtVz4AuHjJANsDQghykn8TGf27pvzE3SFbLaVDg==","signature_status":"signed_v1","signed_at":"2026-05-18T02:55:56.826906Z","signed_message":"canonical_sha256_bytes"},"source_id":"1403.5081","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:1450eff10f4932dcd92bbabc741058fc485f29de131435c17f6ecb0713b49468","sha256:41259d0f083423a6236bcf6b90acee2297940077f0bbb2c62a89e1b5ef44e89c"],"state_sha256":"3a8a20506289377482248644824ff32c708db12f2370356579262a60f0b296ad"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"WcNvVsZxmPEJ9nAf2xEuVTnGYbvADEbiuwKNoM1UvfjY4mnCpR17/pRS1jnk1tLL+nm40opCaMvoqS3oZ668Aw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-27T02:32:10.040703Z","bundle_sha256":"46093ff4a06db4b55d05dcc72cdfab2f844b44e48c931914549cbdcb20ffa155"}}