{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:VYYA5CUNA7I4QONNWNRT7S5GGU","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":"5f490afc1ba7dab32986cb4a1a8e1aa573dfed6b778f26b490518119ab8947f6","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2018-07-18T06:51:16Z","title_canon_sha256":"272d672b768ceb84abd4f799a1ccf94578ca77adbb85d37884efcb4abf44df0c"},"schema_version":"1.0","source":{"id":"1807.07405","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1807.07405","created_at":"2026-05-18T00:10:20Z"},{"alias_kind":"arxiv_version","alias_value":"1807.07405v1","created_at":"2026-05-18T00:10:20Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1807.07405","created_at":"2026-05-18T00:10:20Z"},{"alias_kind":"pith_short_12","alias_value":"VYYA5CUNA7I4","created_at":"2026-05-18T12:32:59Z"},{"alias_kind":"pith_short_16","alias_value":"VYYA5CUNA7I4QONN","created_at":"2026-05-18T12:32:59Z"},{"alias_kind":"pith_short_8","alias_value":"VYYA5CUN","created_at":"2026-05-18T12:32:59Z"}],"graph_snapshots":[{"event_id":"sha256:46c291a18a413e119ee0dc7c5d2daa43487e527c7d4118d8defc5e755c22d6db","target":"graph","created_at":"2026-05-18T00:10:20Z","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 Photoacoustic imaging, Delay-and-Sum (DAS) algorithm is the most commonly used beamformer. However, it leads to a low resolution and high level of sidelobes. Delay-Multiply-and-Sum (DMAS) was introduced to provide lower sidelobes compared to DAS. In this paper, to improve the resolution and sidelobes of DMAS, a novel beamformer is introduced using Eigenspace-Based Minimum Variance (EIBMV) method combined with DMAS, namely EIBMV-DMAS. It is shown that expanding the DMAS algebra leads to several terms which can be interpreted as DAS. Using the EIBMV adaptive beamforming instead of the existin","authors_text":"Ali Mahloojifar, Mahdi Orooji, Manojit Pramanik, Moein Mozaffarzadeh, Vijitha Periyasamy","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2018-07-18T06:51:16Z","title":"Eigenspace-Based Minimum Variance Combined with Delay Multiply and Sum Beamformer: Application to Linear-Array Photoacoustic Imaging"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1807.07405","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:e78facfa509fcd23aeacfae7fbb38c8b8954056554fa976773558c84538201fa","target":"record","created_at":"2026-05-18T00:10:20Z","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":"5f490afc1ba7dab32986cb4a1a8e1aa573dfed6b778f26b490518119ab8947f6","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"eess.SP","submitted_at":"2018-07-18T06:51:16Z","title_canon_sha256":"272d672b768ceb84abd4f799a1ccf94578ca77adbb85d37884efcb4abf44df0c"},"schema_version":"1.0","source":{"id":"1807.07405","kind":"arxiv","version":1}},"canonical_sha256":"ae300e8a8d07d1c839adb3633fcba635276b8a52f40d0e8b1cf022017ec7a04a","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"ae300e8a8d07d1c839adb3633fcba635276b8a52f40d0e8b1cf022017ec7a04a","first_computed_at":"2026-05-18T00:10:20.230515Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:10:20.230515Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"8o0PCl28zUsGTpOdYqvJS3ytdMeP7sl7/tWKRBE0l2eW73z4eFwRKmQMZ23An8YGv0AH8k7zy7PL2Gv0SvZZBw==","signature_status":"signed_v1","signed_at":"2026-05-18T00:10:20.231309Z","signed_message":"canonical_sha256_bytes"},"source_id":"1807.07405","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:e78facfa509fcd23aeacfae7fbb38c8b8954056554fa976773558c84538201fa","sha256:46c291a18a413e119ee0dc7c5d2daa43487e527c7d4118d8defc5e755c22d6db"],"state_sha256":"b364b95d4c38de2783c6d45096e7a99dc7c24fd8a9fd394ad9037f5f6b51fe16"}