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CHAPTER 10: CONCLUSION AND FUTURE WORK
Non Destructive Testing (NDT) is a technique for damage
assessment, disaster prediction and quality control, to detect the defects
without affecting the internal structure. This thesis presents and
proposes some novel techniques for weld flaw classification from
industrial radiography for improving the safety of nuclear power plant,
petrochemical industries etc using image processing and clustering
techniques. Six different novel approaches are conducted and
documented in this thesis for the classification of the weld defect along
with a broad literature survey of various techniques conducted by
numerous researchers in this field. Weld defect classification in
radiographic images using Fuzzy C-Means clustering and Zernike
moments, PCA and K-Means clustering based weld defect identification
from radiographic images, Weld defect recognition in radiography based
on Projection Profile and RST invariant by using LVQ, Detection using
Image reconstruction by Simultaneous Algebraic Reconstruction
Technique (SART), An efficient fast processing Adaptive Median filter
based on enhanced Dijkstras 3-way partitioning is developed in this
thesis, Weld flaw identification from radiographic weld images using
Radon Transform and improved Fuzzy C-Means clustering. This thesis
presents novel approaches for the improvement of automatic
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classification and judgement of discontinuities or defects in welding. The
result shows that these above techniques are robust and provide a good
detection rate for different types of weld flaws. The future scope of this
research work lies in the field of pre-processing, segmentation and
feature extraction. The segmentation and feature extraction techniques
like Watershed, Hough Transform and Zernike Moments respectively are
mathematically and computationally complex due to the morphological
operations, parametric plane conversions and orthogonal projections
respectively, thereby consuming more execution time. So there is always
a future scope for making the image enhancement, segmentation and
feature extraction techniques simpler and more effective by reducing
computational complexity which will help in faster and more accurate
recognition of weld defects from radiographic images.