{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:W43R6XBN6GULZUU3LN7VMUSM5L","short_pith_number":"pith:W43R6XBN","canonical_record":{"source":{"id":"1902.01962","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T22:38:40Z","cross_cats_sorted":["physics.app-ph"],"title_canon_sha256":"a1aa6fcf7b5158d962d9f0760ff6659793a838e419873f19947741c7857ac21d","abstract_canon_sha256":"8970d22832caacf094e8be1b2176ff631797b1188158a0c0b4b6604979b21a97"},"schema_version":"1.0"},"canonical_sha256":"b7371f5c2df1a8bcd29b5b7f56524ceae682d9772b90cfd5054e60adb46aafee","source":{"kind":"arxiv","id":"1902.01962","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1902.01962","created_at":"2026-05-17T23:54:38Z"},{"alias_kind":"arxiv_version","alias_value":"1902.01962v1","created_at":"2026-05-17T23:54:38Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1902.01962","created_at":"2026-05-17T23:54:38Z"},{"alias_kind":"pith_short_12","alias_value":"W43R6XBN6GUL","created_at":"2026-05-18T12:33:30Z"},{"alias_kind":"pith_short_16","alias_value":"W43R6XBN6GULZUU3","created_at":"2026-05-18T12:33:30Z"},{"alias_kind":"pith_short_8","alias_value":"W43R6XBN","created_at":"2026-05-18T12:33:30Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:W43R6XBN6GULZUU3LN7VMUSM5L","target":"record","payload":{"canonical_record":{"source":{"id":"1902.01962","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T22:38:40Z","cross_cats_sorted":["physics.app-ph"],"title_canon_sha256":"a1aa6fcf7b5158d962d9f0760ff6659793a838e419873f19947741c7857ac21d","abstract_canon_sha256":"8970d22832caacf094e8be1b2176ff631797b1188158a0c0b4b6604979b21a97"},"schema_version":"1.0"},"canonical_sha256":"b7371f5c2df1a8bcd29b5b7f56524ceae682d9772b90cfd5054e60adb46aafee","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:54:38.208743Z","signature_b64":"uZol9Um6y20UtqQhWz1cmsukfqJZ8WBQtU357UfS6lUxwM5Zif/dkuujX/FGy8DGcAg8j/fypb0hDXYSVXTHCg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"b7371f5c2df1a8bcd29b5b7f56524ceae682d9772b90cfd5054e60adb46aafee","last_reissued_at":"2026-05-17T23:54:38.208177Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:54:38.208177Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1902.01962","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":"2026-05-17T23:54:38Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"1BPf+YikXthw/IVd8ayOZ1L7djaV3tKeXJ/Wtx/MV6jKQHDOgu4qJP14GxtGCUxCEg708DOxlsgbiiXEAq37Bw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T10:24:52.247349Z"},"content_sha256":"42b718915fb2bbd95b798ff5f418ccc80aab5cb19bc39a75183027e08828c233","schema_version":"1.0","event_id":"sha256:42b718915fb2bbd95b798ff5f418ccc80aab5cb19bc39a75183027e08828c233"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:W43R6XBN6GULZUU3LN7VMUSM5L","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Coupling of Wideband Impulses Generated by Granular Chains into Liquids","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["physics.app-ph"],"primary_cat":"physics.med-ph","authors_text":"D.A. Hutchins, J. Yang, N. Saffari, O. Akanji, P. Gelat, P.J. Thomas, S. Freear, S. Harput","submitted_at":"2019-02-05T22:38:40Z","abstract_excerpt":"An ultrasonic transducer technology to generate wideband impulses using a one-dimensional chain of spheres was previously presented. The Hertzian contact between the spheres causes the nonlinearity of the system to increase, which transforms high amplitude narrowband sinusoidal input into a train of wideband impulses. Generation of short duration ultrasonic pulses is desirable both in diagnostic and therapeutic ultrasound. Nevertheless, the biggest challenge in terms of adaptation to biomedical ultrasound is the coupling of the ultrasonic energy into biological tissue.\n  An analytical model wa"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1902.01962","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":"2026-05-17T23:54:38Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"NQb+F2oeyacF5N9b45Ci1UvoC8lT9xPmGc3NMTG7lqnHoDD1rw2Ec5e2u0bzavARH5DTldMeVr4zOFJfJzJqDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T10:24:52.247700Z"},"content_sha256":"c21f1c9474e77c11dfaf54b8877c69a875f066b0d5a58f1fd6f378d14e1a4718","schema_version":"1.0","event_id":"sha256:c21f1c9474e77c11dfaf54b8877c69a875f066b0d5a58f1fd6f378d14e1a4718"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/W43R6XBN6GULZUU3LN7VMUSM5L/bundle.json","state_url":"https://pith.science/pith/W43R6XBN6GULZUU3LN7VMUSM5L/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/W43R6XBN6GULZUU3LN7VMUSM5L/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":"2026-06-07T10:24:52Z","links":{"resolver":"https://pith.science/pith/W43R6XBN6GULZUU3LN7VMUSM5L","bundle":"https://pith.science/pith/W43R6XBN6GULZUU3LN7VMUSM5L/bundle.json","state":"https://pith.science/pith/W43R6XBN6GULZUU3LN7VMUSM5L/state.json","well_known_bundle":"https://pith.science/.well-known/pith/W43R6XBN6GULZUU3LN7VMUSM5L/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:W43R6XBN6GULZUU3LN7VMUSM5L","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":"8970d22832caacf094e8be1b2176ff631797b1188158a0c0b4b6604979b21a97","cross_cats_sorted":["physics.app-ph"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T22:38:40Z","title_canon_sha256":"a1aa6fcf7b5158d962d9f0760ff6659793a838e419873f19947741c7857ac21d"},"schema_version":"1.0","source":{"id":"1902.01962","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1902.01962","created_at":"2026-05-17T23:54:38Z"},{"alias_kind":"arxiv_version","alias_value":"1902.01962v1","created_at":"2026-05-17T23:54:38Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1902.01962","created_at":"2026-05-17T23:54:38Z"},{"alias_kind":"pith_short_12","alias_value":"W43R6XBN6GUL","created_at":"2026-05-18T12:33:30Z"},{"alias_kind":"pith_short_16","alias_value":"W43R6XBN6GULZUU3","created_at":"2026-05-18T12:33:30Z"},{"alias_kind":"pith_short_8","alias_value":"W43R6XBN","created_at":"2026-05-18T12:33:30Z"}],"graph_snapshots":[{"event_id":"sha256:c21f1c9474e77c11dfaf54b8877c69a875f066b0d5a58f1fd6f378d14e1a4718","target":"graph","created_at":"2026-05-17T23:54:38Z","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":"An ultrasonic transducer technology to generate wideband impulses using a one-dimensional chain of spheres was previously presented. The Hertzian contact between the spheres causes the nonlinearity of the system to increase, which transforms high amplitude narrowband sinusoidal input into a train of wideband impulses. Generation of short duration ultrasonic pulses is desirable both in diagnostic and therapeutic ultrasound. Nevertheless, the biggest challenge in terms of adaptation to biomedical ultrasound is the coupling of the ultrasonic energy into biological tissue.\n  An analytical model wa","authors_text":"D.A. Hutchins, J. Yang, N. Saffari, O. Akanji, P. Gelat, P.J. Thomas, S. Freear, S. Harput","cross_cats":["physics.app-ph"],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T22:38:40Z","title":"Coupling of Wideband Impulses Generated by Granular Chains into Liquids"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1902.01962","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":"sha256:42b718915fb2bbd95b798ff5f418ccc80aab5cb19bc39a75183027e08828c233","target":"record","created_at":"2026-05-17T23:54:38Z","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":"8970d22832caacf094e8be1b2176ff631797b1188158a0c0b4b6604979b21a97","cross_cats_sorted":["physics.app-ph"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.med-ph","submitted_at":"2019-02-05T22:38:40Z","title_canon_sha256":"a1aa6fcf7b5158d962d9f0760ff6659793a838e419873f19947741c7857ac21d"},"schema_version":"1.0","source":{"id":"1902.01962","kind":"arxiv","version":1}},"canonical_sha256":"b7371f5c2df1a8bcd29b5b7f56524ceae682d9772b90cfd5054e60adb46aafee","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"b7371f5c2df1a8bcd29b5b7f56524ceae682d9772b90cfd5054e60adb46aafee","first_computed_at":"2026-05-17T23:54:38.208177Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:54:38.208177Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"uZol9Um6y20UtqQhWz1cmsukfqJZ8WBQtU357UfS6lUxwM5Zif/dkuujX/FGy8DGcAg8j/fypb0hDXYSVXTHCg==","signature_status":"signed_v1","signed_at":"2026-05-17T23:54:38.208743Z","signed_message":"canonical_sha256_bytes"},"source_id":"1902.01962","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:42b718915fb2bbd95b798ff5f418ccc80aab5cb19bc39a75183027e08828c233","sha256:c21f1c9474e77c11dfaf54b8877c69a875f066b0d5a58f1fd6f378d14e1a4718"],"state_sha256":"810295056fb55057c2250d11e515dded9ec1e20ee571cd8cce1d74afc06e5333"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"F3rEw7027MpR5GFbYkGp/V0sQ3X1Ph/wBzzgh7mKqPK10jxtQMnaHe6xphX9ssOaeaxjodAIkMOR8x6yI+uNAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-07T10:24:52.249668Z","bundle_sha256":"8edc1932888f96fe4827aa30598323a283691ed7a795268aaa3f1384100022df"}}