Concept of effective atomic number and effective mass density in dual-energy X-ray computed tomography

Bonnin, Anne; Duvauchelle, Philippe; Kaftandjian, Valérie; Ponard, Pascal

doi:10.1016/j.nimb.2013.09.012

Cited by 45 publications

(40 citation statements)

References 20 publications

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“…Along with density, these two parameters are the primary features used by software algorithms to detect explosives in scanned baggage. However, effective atomic number is a (semi-) empirical parameter, and there are multiple definitions in literature [27]. In this work, we adopted a definition and algorithm for determining effective atomic number developed by the Lawrence Livermore National Laboratory [28,29].…”

Section: Selection Of Simulant Ingredientsmentioning

confidence: 99%

A Powdered Simulant of Triacetone Triperoxide (TATP) for Safe Testing of X-ray Transmission Screening Equipment

et al. 2020

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Explosives detection systems (EDS) based on X-ray are used at airports to screen baggage for the presence of explosives. Once EDS are installed in airports, however, it can be challenging to test the EDS equipment and verify that it continues to perform at the highest level, because of the impracticality of introducing bulk explosives into civil aviation airports. The problem is particularly acute for sensitive homemade explosives, such as triacetone triperoxide (TATP). This paper describes our work to develop a safe, accurate and stable simulant for TATP for EDS based on X-ray transmission. Bulk quantities of TATP were synthesised and characterised especially for this project, and we describe the unique challenges and safety considerations of collecting this data. Our calculations show that the expanded measurement uncertainty with a coverage factor of k = 2 is 5.7% for bulk density and 1.0% for Zeff at 24 months.

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Section: Selection Of Simulant Ingredientsmentioning

confidence: 99%

A Powdered Simulant of Triacetone Triperoxide (TATP) for Safe Testing of X-ray Transmission Screening Equipment

et al. 2020

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“…For example, the constants a and b are usually calibrated by scanning standard materials with known ρ e and Z eff . The values of n and y are often inferred from the literature, with n usually between 3 and 4 (Alves et al, ; Bonnin et al, ; Jussiani & Appoloni, ; Landry et al, ; Torikoshi et al, ; Van Geet et al, ; Wildenschild et al, ; Wellington & Vinegar, ), while y is often close to 3 (Haghighi et al, ; Van Geet et al, ; Wellington & Vinegar, ).…”

Section: Fundamentals Of Dectmentioning

confidence: 99%

“…Dashed lines in Figures 4b and 4c show Gaussian least squares fits to the normalized histograms, assumed as the probability density functions for the attenuation coefficients. ImageJ (Schindelin et al, 2012) plug-in is available (Behnel & Wagner, 2016). Figure 6 compares the results of noise attenuation with the NLM and the median filters.…”

Section: Preprocessing: Noise Estimationmentioning

confidence: 99%

Monte Carlo Approach for Estimating Density and Atomic Number From Dual‐Energy Computed Tomography Images of Carbonate Rocks

2017

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We develop a new Monte Carlo‐based inversion method for estimating electron density and effective atomic number from 3‐D dual‐energy computed tomography (CT) core scans. The method accounts for uncertainties in X‐ray attenuation coefficients resulting from the polychromatic nature of X‐ray beam sources of medical and industrial scanners, in addition to delivering uncertainty estimates of inversion products. Estimation of electron density and effective atomic number from CT core scans enables direct deterministic or statistical correlations with salient rock properties for improved petrophysical evaluation; this condition is specifically important in media such as vuggy carbonates where CT resolution better captures core heterogeneity that dominates fluid flow properties. Verification tests of the inversion method performed on a set of highly heterogeneous carbonate cores yield very good agreement with in situ borehole measurements of density and photoelectric factor.

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“…Several solutions to the problem of scanning plate-like objects with high aspect ratios have been explored, including dual-energy scanning [30][31][32][33], and region of interest (ROI) scanning [16,17].…”

Section: Introductionmentioning

confidence: 99%

Spatial resolution of a laboratory based X-Ray cone-beam laminography scanning system for various trajectories

Deyhle

Towsyfyan

Biguri

et al. 2020

NDT & E International

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Computed laminography (CL), a long established NDT method, is ideal for the non-destructive evaluation of plate-like structures, for which conventional computed tomography (CT) is less well suited. This paper demonstrates the feasibility of implementing raster CL on a Nikon Metrology custom build X-ray CT scanner without the need for specialised equipment. To provide a more principled way to demonstrate the widespread adoption of CL for defect characterization in plate-like structures, a test specimen was designed and manufactured from Polyoxymethylene (Delrin) that allows well defined features of different size and orientation to be characterized. The study highlights the relation between direction-dependent spatial resolution, feature geometry and scan trajectory. It demonstrates that high-resolution and highspeed in situ volume-imaging of plate-like structures with large aspect ratios is viable at levels that would be challenging via CT or alternative three-dimensional NDT methods.

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Concept of effective atomic number and effective mass density in dual-energy X-ray computed tomography

Cited by 45 publications

References 20 publications

A Powdered Simulant of Triacetone Triperoxide (TATP) for Safe Testing of X-ray Transmission Screening Equipment

A Powdered Simulant of Triacetone Triperoxide (TATP) for Safe Testing of X-ray Transmission Screening Equipment

Monte Carlo Approach for Estimating Density and Atomic Number From Dual‐Energy Computed Tomography Images of Carbonate Rocks

Spatial resolution of a laboratory based X-Ray cone-beam laminography scanning system for various trajectories

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