&lt;title&gt;X-ray and gamma-ray computed tomography for industrial nondestructive testing and evaluation&lt;/title&gt;

Costello, Ian; Wells, P.N.T.; Davis, John R.; Benci, N.; Skerrett, David; Davies, D.R.

doi:10.1117/12.171265

Cited by 3 publications

(3 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To address these weaknesses in the bubble observation techniques, researchers need to investigate the noncontact ''tomography'' observation methods, including Optical Coherence Tomography (OCT), and X-ray and the gamma-ray computed tomographies, which traditionally have been used as nondestructive evaluation techniques [72,73]. X-raycomputed tomography is a particularly appealing candidate for a real-time measurement of bubbles (or moving ''porosities'') because it has been used successfully to measure porosities in other manufacturing processes [74][75][76].…”

Section: A Need For Accurate Experimental Observation Of Partial Saturation and Bubble Motionmentioning

confidence: 99%

Modeling the Unsaturated Flow in Liquid Composite Molding Processes: A Review and Some Thoughts

Pillai

2004

Journal of Composite Materials

122

View full text Add to dashboard Cite

The liquid composite molding (LCM) processes for manufacturing polymer composites involve injecting a thermoset resin into a fiber-packed mold cavity. Very often, the fiber preform behind the resin front is partially saturated during the mold-filling process in LCM, giving rise to an unsaturated flow in that region. This paper first discusses the role of dual-scale porous media in inducing unsaturated flow in certain directional (woven, stitched, or braided) mats due to the delayed impregnation of tows. The approach of using a sink term in the mass balance equation is compared with the traditional approach of using unsaturated permeability for modeling unsaturated flow in dual-scale directional mats. Later, the relation of unsaturated flow with the phenomenon of bubble formation and migration is discussed. The lack of connection between the unsaturated flow research on the one hand, and the bubble creation and migration research on the other, is highlighted next. A few suggestions are offered on related topics, including the modeling of bubble motion, and the need for accurate experiments in unsaturated flow.

show abstract

Section: A Need For Accurate Experimental Observation Of Partial Saturation and Bubble Motionmentioning

confidence: 99%

Modeling the Unsaturated Flow in Liquid Composite Molding Processes: A Review and Some Thoughts

Pillai

2004

Journal of Composite Materials

122

View full text Add to dashboard Cite

show abstract

“…Since the introduction of computed tomography (CT) in 1972, CT became one of the most effective non-invasive imaging techniques used in not only medical applications such as diagnostic imaging and interventional imaging, but also industrial nondestructive testing and evaluation (NDT/NDE) applications such as mechanical part manufacturing, composite material production, oil and gas pipeline evaluation, electronic circuit board inspection, and even archeological artifacts investigation [7,13].…”

Section: Introductionmentioning

confidence: 99%

Parametric boundary reconstruction algorithm for industrial CT metrology application

Yin

Khare

Man

2009

Journal of X-Ray Science and Technology

View full text Add to dashboard Cite

High-energy X-ray computed tomography (CT) systems have been recently used to produce high-resolution images in various nondestructive testing and evaluation (NDT/NDE) applications. The accuracy of the dimensional information extracted from CT images is rapidly approaching the accuracy achieved with a coordinate measuring machine (CMM), the conventional approach to acquire the metrology information directly. On the other hand, CT systems generate the sinogram which is transformed mathematically to the pixel-based images. The dimensional information of the scanned object is extracted later by performing edge detection on reconstructed CT images. The dimensional accuracy of this approach is limited by the grid size of the pixel-based representation of CT images since the edge detection is performed on the pixel grid. Moreover, reconstructed CT images usually display various artifacts due to the underlying physical process and resulting object boundaries from the edge detection fail to represent the true boundaries of the scanned object.In this paper, a novel algorithm to reconstruct the boundaries of an object with uniform material composition and uniform density is presented. There are three major benefits in the proposed approach. First, since the boundary parameters are reconstructed instead of image pixels, the complexity of the reconstruction algorithm is significantly reduced. The iterative approach, which can be computationally intensive, will be practical with the parametric boundary reconstruction. Second, the object of interest in metrology can be represented more directly and accurately by the boundary parameters instead of the image pixels. By eliminating the extra edge detection step, the overall dimensional accuracy and process time can be improved. Third, since the parametric reconstruction approach shares the boundary representation with other conventional metrology modalities such as CMM, boundary information from other modalities can be directly incorporated as prior knowledge to improve the convergence of an iterative approach. In this paper, the feasibility of parametric boundary reconstruction algorithm is demonstrated with both simple and complex simulated objects. Finally, the proposed algorithm is applied to the experimental industrial CT system data.

show abstract

“…INTRODUCTION T here are many scan modes in industrial computed tomography(also called ICT) [1], [2], [3], [4]. Therefore it is very necessary to study the related reconstruction algorithms [5] in ICT.…”

mentioning

confidence: 99%

The convolution back projection algorithm based on windows function

2005

2005 IEEE International Conference on Granular Computing

View full text Add to dashboard Cite

In this paper, some efficient image reconstruction algorithms in industrial computed tomography with the fanbeam projection based on windows function was discussed in detail. In order to improve the quality of image reconstruction, windows functions of image reconstruction of convolution back projection was proposed. The windows functions method ameliorates the process of image reconstruction. The efficiency of windows function is evaluated in contrast to that of its traditional serial counterpart. Experiment results clearly demonstrate that windows function can efficiently improve quality of images reconstruction.Index Terms-windows function, convolution back projection, fan-beam scan mode, interpolation.

show abstract

<title>X-ray and gamma-ray computed tomography for industrial nondestructive testing and evaluation</title>

Cited by 3 publications

References 5 publications

Modeling the Unsaturated Flow in Liquid Composite Molding Processes: A Review and Some Thoughts

Modeling the Unsaturated Flow in Liquid Composite Molding Processes: A Review and Some Thoughts

Parametric boundary reconstruction algorithm for industrial CT metrology application

The convolution back projection algorithm based on windows function

Contact Info

Product

Resources

About