CT Data of a Pen-Spring: Application to Under-Sampled Dynamic X-ray Tomography

Juliaana Juurakko; Simo S\"arkk\"a; Zenith Purisha

arxiv: 1907.01871 · v1 · pith:ZH4P4L3Lnew · submitted 2019-07-03 · ⚛️ physics.med-ph · eess.IV

CT Data of a Pen-Spring: Application to Under-Sampled Dynamic X-ray Tomography

Juliaana Juurakko , Zenith Purisha , Simo S\"arkk\"a This is my paper

Pith reviewed 2026-05-25 09:48 UTC · model grok-4.3

classification ⚛️ physics.med-ph eess.IV

keywords computed tomographypen-springsinogramsunder-sampledfan-beamX-rayopen datadynamic tomography

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The pith

The paper releases an open CT dataset of a pen-spring consisting of under-sampled sinograms from fan-beam X-ray measurements for use in dynamic tomography research.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

This paper provides documentation for a publicly available dataset of computed tomography data from a pen-spring. The dataset features X-ray sinograms of a 2D slice obtained by down-sampling measured sinograms with 10 or 100 projections in fan-beam geometry and applying logarithms. It also supplies the original measured sinograms and the corresponding measurement matrices. The data is made available on Zenodo for free scientific use, with a request to cite both the data and the document.

Core claim

The paper establishes a reusable CT dataset for a pen-spring that includes processed sinograms (finalSino) derived from limited-projection fan-beam measurements, enabling applications in under-sampled dynamic X-ray tomography.

What carries the argument

The finalSino, which is the processed X-ray sinogram data from the pen-spring slice obtained via down-sampling and logarithm from 10-projection or 100-projection measurements.

If this is right

The dataset supports development of algorithms for reconstructing images from under-sampled data.
It allows comparison between reconstructions from 10 and 100 projections.
Provides real measurement matrices for accurate modeling in tomography simulations.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

This data could serve as a benchmark for various dynamic tomography methods not mentioned in the paper.
Researchers might explore its use in other imaging modalities or with different noise models.
It highlights the potential for open data in advancing under-sampled imaging techniques.

Load-bearing premise

The original measured sinograms accurately capture the pen-spring geometry under the stated fan-beam setup and the processing steps preserve information relevant to tomography tasks.

What would settle it

Performing a tomography reconstruction on the provided finalSino data and finding that the resulting image does not match the known structure of a pen-spring would indicate issues with the dataset.

read the original abstract

This is the documentation of Computed Tomography (CT) data of a pen-spring. The open data set is available at https://zenodo.org/record/3266936#.XRyMdCZS9oA and can be freely used for scientific purposes with appropriate references to the data and to this document in arxiv.org. The provided data set includes the X-ray sinograms ({\tt finalSino}) of a single 2D slice from a different height of the spring. The {\tt finalSino} was obtained from a measured 10-projection or 100-projection {\tt sinogram} using fan-beam geometry by down-sampling and taking logarithms. The data set includes also those original measured {\tt sinogram}s and corresponding measurement matrices.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Desk Editor's Note private letter to a colleague

This is a clean data-release paper documenting measured fan-beam sinograms of a pen-spring with the processing steps spelled out.

read the letter

This paper releases measured X-ray sinograms of a pen spring, both the original 10-projection and 100-projection versions under fan-beam geometry and the down-sampled logged versions, plus the measurement matrices. The main contribution is making those files public on Zenodo with a short description of how the finalSino files were created from the raw measurements by down-sampling and taking logarithms. That is the whole paper. It does the documentation part clearly and without overclaiming. The abstract and text state exactly what is included and how it was derived, which is the right level for a data note. No derivations or predictions are attempted, so there is nothing to check for circularity or fitting issues. The soft spot is that the work stops at release. There are no reconstruction results, no tests of algorithms on the data, and no discussion of what information might be lost in the down-sampling step. That is not a flaw in a data paper, but it does mean the value is entirely in whether other people find the measurements useful for under-sampled tomography work. The assumption that the original scans accurately reflect the spring geometry is standard and not load-bearing here because no claims are made about reconstruction quality. This is for algorithm developers who want real measured sinograms rather than simulations. A reader looking for new methods or findings will not get much, but someone needing open fan-beam data at low projection counts might. It is honest documentation of existing measurements, so it deserves a serious referee rather than a desk reject. I would send it out for review.

Referee Report

0 major / 2 minor

Summary. The manuscript documents the public release of CT data for a pen-spring, consisting of measured sinograms (10- or 100-projection, fan-beam geometry), the processed finalSino obtained via down-sampling and logarithm, and the associated measurement matrices. The data set is hosted on Zenodo and intended for use in under-sampled dynamic X-ray tomography research.

Significance. If the data files match the described acquisition and processing steps, the release supplies a real measured benchmark with both raw and processed sinograms plus explicit measurement matrices, which is useful for testing limited-projection reconstruction methods.

minor comments (2)

[Abstract] Abstract: the phrase 'a single 2D slice from a different height of the spring' is ambiguous; the reference height or the relation to any other slices should be stated explicitly.
The exact numerical parameters of the fan-beam geometry (source-to-detector distance, fan angle, etc.) and the precise down-sampling rule used to produce finalSino from the measured sinogram should be given in the main text or a methods section.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for their positive review and recommendation to accept the manuscript.

Circularity Check

0 steps flagged

No significant circularity

full rationale

This is a pure data-release and documentation paper. The abstract and full text describe measured sinograms, down-sampling, and logarithm processing under fan-beam geometry, but contain no derivations, predictions, fitted parameters, or load-bearing claims that reduce to self-citation or definition. The contribution is the public availability of the data set itself; no modeling chain exists to inspect for circularity.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

No free parameters, axioms, or invented entities are introduced because the paper contains no theoretical claims or derivations.

pith-pipeline@v0.9.0 · 5671 in / 962 out tokens · 29538 ms · 2026-05-25T09:48:14.445141+00:00 · methodology

CT Data of a Pen-Spring: Application to Under-Sampled Dynamic X-ray Tomography

Core claim

What carries the argument

If this is right

Where Pith is reading between the lines

Load-bearing premise

What would settle it

discussion (0)