Pith Number

pith:M6LXMGGU

pith:2026:M6LXMGGUKLVCKQ5PGKQRVBOXC2

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Shift- and stretch-invariant non-negative matrix factorization with an application to brain tissue delineation in emission tomography data

Anders S. Olsen, Claus Svarer, Gitte M. Knudsen, Jesper L. Hinrich, Miriam L. Navarro, Morten M{\o}rup

A frequency-domain non-negative matrix factorization accounts for temporal shifts and stretching to better delineate brain tissue in emission tomography.

arxiv:2604.08161 v1 · 2026-04-09 · cs.LG

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\pithnumber{M6LXMGGUKLVCKQ5PGKQRVBOXC2}

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Claims

C1strongest claim

We demonstrate on synthetic data and brain emission tomography data that the model is able to account for stretching to provide more detailed characterization of brain tissue structure.

C2weakest assumption

That frequency-domain phase modifications and zero-padding/truncation can accurately recover non-integer shifts and stretches without introducing significant artifacts or violating non-negativity in real emission tomography data.

C3one line summary

A new NMF variant estimates integer and non-integer temporal shifts plus stretching in the frequency domain to improve brain tissue delineation in emission tomography data.

References

20 extracted · 20 resolved · 0 Pith anchors

[1] Partial volume effect in SPECT & PET imaging and impact on radionuclide dosimetry es- timates 2023 · doi:10.22038/aojnmb.2022.63827.1448

[2] Automatic seg- mentation of dynamic neuroreceptor single-photon emission tomog- raphy images using fuzzy clustering 1999 · doi:10.1007/s002590050425

[3] CHAPTER 59 - A Cluster Analysis Approach for the Characteriza- tion of Dynamic PET Data 1996 · doi:10.1016/b978-012389760-2/50061-

[4] Delineation and quantitation of brain lesions by fuzzy clustering in Positron Emission Tomography, 1996

[5] Segmentation of Dynamic Total-Body [18F]-FDG PET Images Using Unsupervised Cluster- ing, 2023

Receipt and verification

First computed	2026-06-02T02:04:52.882910Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

67977618d452ea2543af32a11a85d716ba48a14fd0d677830c2a5343bc2e028c

Aliases

arxiv: 2604.08161 · arxiv_version: 2604.08161v1 · doi: 10.48550/arxiv.2604.08161 · pith_short_12: M6LXMGGUKLVC · pith_short_16: M6LXMGGUKLVCKQ5P · pith_short_8: M6LXMGGU

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Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/M6LXMGGUKLVCKQ5PGKQRVBOXC2 \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 67977618d452ea2543af32a11a85d716ba48a14fd0d677830c2a5343bc2e028c

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "b501ecf4501f23e14138a5f3797d2ed5cc7135681b9d3323a62a2c14c985eb62",
    "cross_cats_sorted": [],
    "license": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
    "primary_cat": "cs.LG",
    "submitted_at": "2026-04-09T12:22:04Z",
    "title_canon_sha256": "729f7bba459cc98088b403a546e85c92e6e9eb7ca734d1603b6da7ce19fe2c7b"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2604.08161",
    "kind": "arxiv",
    "version": 1
  }
}