*Editorial* **Special Issue: Novel Approaches for Nondestructive Testing and Evaluation**

**Jinyi Lee 1,2,3,\*, Hoyong Lee <sup>4</sup> and Azouaou Berkache <sup>1</sup>**


### **1. Introduction**

Nondestructive testing and evaluation (NDT&E) is one of the most important techniques for determining the quality and safety of materials, components, devices, and structures. NDT&E technologies include ultrasonic testing (UT), magnetic particle testing (MT), magnetic flux leakage testing (MFLT), eddy current testing (ECT), radiation testing (RT), penetrant testing (PT), and visual testing (VT), and these are widely used throughout modern industries. However, some NDT processes, such as cleaning specimens and removing paint, cause environmental pollution and must be inspected in limited environments (time, space, and sensor selection). Thus, NDT&E is classified as a typical 3D (dirty, dangerous, and difficult) job. In addition, the NDT operator judges the presence of damage by experience and subjective judgment, so in some cases, a flaw that exists may not be detected during the test. Therefore, to obtain clearer test results, a means for the operator to determine the flaw more easily should be provided. In addition, the test results should be organized systemically, in order to identify the cause of the abnormality in the test specimen and to identify the progress of the damage quantitatively.

Thus far, from a total of 18 submitted papers to this Special Issue, 13 have been published. The next sections provide a brief summary of each of the papers published.
