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[en] In this study, 3D shape measurement and path design methods for automatic nondestructive testing were investigated. A rotation was added to the 2D shape measurement sensor, and the point cloud data obtained from the measurements was visualized using a mesh generated in MATLAB. The visualized data was re-meshed to generate inspection points and inspection directions to produce a uniform mesh size. The inspection path obtained using the calculated data is zigzag in shape, since this path was inefficient, optimization was performed. The optimization method aims to minimize the path by maintaining the inspection direction and aligning the inspection position to the same height, thereby eliminating the problem of continuous shaking. Through this study, we have confirmed the possibility of automated, non-destructive inspection systems using shape information
[en] This paper accounts axisymmetric contact problems of interaction between rigid punch and poroelastic layer based on Cowin–Nunziato poroelastic theory. It is supposed that punch’s foundation shape is a flat or a paraboloid and there is no contact friction. Using Hankel’s integral transform the formulated contact problems are reduced to the integral equations with unknown contact stress. To solve these integral equations we used the collocation technique. In the case of parabolic punch the values of the contact stress and the contact area have been determined and discussed. The relationship between the force acting on the punch and the punch displacements is investigated, which is one of the main characteristics in determining the mechanical parameters of a material by the indentation method. A comparative analysis of the studied characteristics of the contact problem is carried out for various values of the porosity and layer’s thickness.
[en] Various tubular objects are utilized for strategic and critical applications in nuclear, aviation, space and petrochemical industries. Major tubular objects employed in these industries are tubes, pipes and vessels which are inspected for planar and volumetric defects hidden inside the material. Various Non-Destructive Testing (NDT) techniques are used for the inspection of such circular objects both during fabrication as well as during in-service stages. Non-Destructive Evaluation (NDE) of these components is carried out in conformance with various codes and standards such as ASME, ASTM and IIW etc. Ultrasonic Testing (UT) is a well-known NDT technique to perform flaw detection, sizing and characterization of tubular objects. Other than the accurate measurement of loss of wall thickness, measurement of variation in Inner Diameter (ID) and Outer Diameter (OD) is also an important requirements of tubes and pipes. Ultrasonic imaging systems are utilized for volumetric inspection of the desired region of tubes and pipes. Imaging systems provide both the gauging and imaging operations. Such a high-speed generic system capable of both, B/C-Scan imaging and high resolution gauging of tubes and pipes, is the requirement of critical applications. Ultrasonic Testing (UT) method, currently used for tube inspection, is not always adequate for flaw characterization. Utilities occasionally experience problems trying to characterize a flaw (particularly, crack or an off-axis flaw) and define its shape, orientation and size. Typically, the Normal Beam (NB) longitudinal waves and angle beam shear waves employing the Pulse-Echo (PE) or Pitch-Catch (PC) technique are used for tube/pipe testing to detect, characterize and size the flaws located within the tube wall or on the ID region or the OD region of tube/ pipe. (author)
[en] Neodymium (Nd) is one of the fission product isotopes used as an indicator of nuclear fuel burn-up because Nd isotope is a stable fission product, has a sufficiently great yield, is not volatile and has low neutron-capture cross-section. Burn-up determination using Nd can support and verify the results of the burn-up determined by using Cs, U and Pu isotopes. Destructive burn-up determination (Destructive Test, DT) is based on the determination of specific isotopes that is performed physico chemically using mass spectrometer equipment. Based on ASTM E 321-69 method for Nd isotope analysis, Nd separation from Ce is required because 142Ce isotope interferes with 142Nd measurement due to their being isobars, and this phenomenon will affect the results of the burn-up calculations. In addition, Nd isotope in U3Si2/Al fuel is present along with other fission isotopes such as 235U, 239Pu, 148Nd, 137Cs, 152Eu, 90Sr, 143Ce, 103Ru, 95Zr, and 95Nb. Therefore, to obtain an accurate value to be used as burn-up indicator, the isotopes must be separated. Before the Nd and Ce separation, several separation phases of Cs isotopes (137Cs, 134Cs) , U isotopes (234U, 235U, 236U, 238U), Pu isotopes (239Pu, 238Pu) and other isotopes (152Eu, 90Sr, 103Ru, 95Zr and 95Nb) were done. The determination of separation recovery aimed to determine the amount of Nd and Ce at each stage of the separation process of other isotopes prior to the separation stage of Nd and Ce. The determination of recovery was conducted by a simulation of fresh U3Si2/Al solution plus standard solutions of Cs, U, Nd and Ce. The recovery for Nd and Ce from Cs separation phase using zeolites were 69.91 % and 64.42 % respectively while the recovery of Nd and Ce at Pu and U separation phase were close to 100 %. The recovery values of Nd and Ce were then used as a correction in the calculation of Nd and Ce separation from the fuel solution, and the corrected values can then be used as a reference in determining the burn-up of U3Si2/Al fuel using Nd as an indicator. (author)
[en] In the present study, the partial loss and distortion of turbine blades were acoustically detected while the turbine was rotating. An ultrasonic signal of a specific frequency (300 kHz) was transmitted in the form of continuous sine waves to the rotating turbine model. The signal was reflected on the turbine blade and received by a receiver. The amplitude of the given frequency component in the received signal was analyzed by signal processing. Because ultrasounds are attenuated easily when propagated into air and have a straight characteristic like light, the characteristics of the signals were examined by a quantitative test. The signal attenuation with respect to distance and the signal reduction by eccentricity were observed and compared with the experimental results. Partial loss decreased the sound reflection area; thus, the signal amplitude was reduced. The signal amplitude was inversely proportional to the size of the defect. Distortion caused larger eccentricity between the transmitter and the receiver. Weaker signals were detected with the more distorted blade. When the blade was distorted by more than 20 dg, the amplitude of the signal decreased significantly. In short, defects of turbine blades cause a reduction in the acoustic signal. It was verified that acoustic diagnosis can be applied to detect the partial loss and distortion of turbine blades.
[en] Segmented Gamma Scanner (SGS) is a commonly used nondestructive testing (Non-Destructive Assay NDA) method. SGS uses radial rotation, axial segmentation, segmented scanning of the non-uniform sample of the "homogenization", making it possible to accurately measure the radioactivity on each segment and is currently widely used in the field of arms control. This paper introduces a self-designed SGS measuring device and uses this device to perform a large number of sub-scanning experiments on different measurement objects in the laboratory. It also studied the detection performance, stability and SGS method of different objects the accuracy of the measurement results.
[en] The goal of the present work is to show the results of the thermal modelling of a transport container of irradiated targets. The particularity of the current modelling is the use of critical variables obtained from a model adjustment. This adjustment is possible thanks to a special tool of the Thermal Desktop code  which allows to adjust such critical variables through the temperature measurements obtained from a real thermal test and used as input data. (author)
[en] Active infrared thermography has been proved as a reliable method for nondestructive testing of various materials and structures. However, limitations such as uneven heating, low spatial resolution, environmental noise and low resolution of infrared cameras, and low number of acquired images make it difficult to quantify defects. Signal processing techniques are required to improve defect quantification. In this paper, a wavelet transform method for defect quantification is studied. Square defects of various sizes and diameters were considered for aluminum specimens. Phase angle data were collected by applying wavelet transform to the thermal image sequence obtained using pulsed thermography. Conclusively, defect detection was evaluated by the phase contrast between sound and defect region, and then the effects of wavelet parameters scale and shift were studied
[en] Neutron imaging offers unique capabilities not limited to the structural characterisation of materials, components and processes at a large variety of neutron sources and thus is highly qualified to be a prime candidate for instrumentation at compact neutron sources. The peculiar characteristics of neutrons, and in particular the cross sections for their interaction with matter enable imaging results that are directly comparable but, most notably, are effectively complementary to those of wide spread X-ray imaging characterisation. Here, it is highlighted how neutron imaging can significantly add to the value and the versatility of basically all and especially future compact neutron sources. Diverse advantages are identified at all possible sizes and levels of sophistication of compact sources. These areas range from source characterisation and students training to state of the art neutron imaging in 3D to applications and method development, which are possible at compact sources and some of which can take particular advantage of advanced source characteristics such as e.g. several target stations at a single accelerator. (authors)
[en] The purpose of this study was to develop radiation safety education (RSE) contents for the radiographic test (RT) using a 3D-simulator base on the on Unreal Engine. Based systematic approach to training (SAT), the RSE contents development was divided into analysis of training needs, design of training program, development of training materials, implementation of training, and evaluation of training effectiveness. The satisfaction research of education contents targeting expert advisory committee and trainees was very high. Therefore, RSE contents were decide to facilitate visualizing and synchronizing the 3D rendering images in real time by providing practical-centered education of RT working environment, and be able to do realistic onsite education through indirect experience of virtual reality (VR) by using observer sight application technique