Fractures and damages can be resulted from physical stresses in the flawed parts of an aircraft. The exact detection of internal defects is possible by radiography testing. The determination of the defects locations by the experts depends on the accuracy, skill and quality of the radiographs. Many of the produced images by industrial radiography are not clear, and it is difficult to accurately detect their defects; hence, the processing methods can help to better investigation of the defects. These images suffer from some opaqueness due to the inherent dispersion of X-rays. In this study, a NON-LOCAL mean method based on the detection of similar pixels in a neighboring area is used to identify corrosion areas. In the method, the image is split into smaller windows and the similar pixel is found on these parts. The results of the method show that, due to the lack of noise function in radiographic images, the background elimination method is more suitable for this algorithm. In this research, the large amount of standard deviation of the noise is considered and background is extracted, the obtained image was reduced from the original radiographic image. The reconstructed image has sharp edges that more clearly indicates the defect area. The evaluation of the results by radiography experts showed that this method has the efficiency to detect defects.

In this paper, a nonlocal foundation model is proposed to analyze the vibration and instability of a Y-shaped single-walled carbon nanotube (Y-SWCNT) conveying fluid. In order to achieve more accurate results, fourth order beam theory is utilized to obtain strain-displacement relations. For the first time, a nonlocal model is presented based on nonlocal elasticity and the effects of nonlocal forces from adjacent and non-adjacent elements on deflection are considered. The Eringen’s theory is utilized due to its capability to consider the size effect. Based on Hamilton’s principle, motion equations as well as boundary conditions are derived and solved by MEANS of hybrid analytical-numerical method. It is believed that the presented general foundation model offers an exact and effective new approach to investigate vibration characteristics of this kind of structures embedded in an elastic medium. The results of this investigation may provide a useful reference in controlling systems in nano-scale.

Given the importance of the rock mass rating classification system in rock engineering, the aim of this paper is to improve final classes of this classification system using k-MEANS and fuzzy c-MEANS clustering algorithms. The data classification in the rock mass rating classification system were allocated to certain classes via a set of initial information based on the opinions and judgments of experience, which the use of clustering algorithms in this system of classification, dataset were divided into specific classes after going through the stages of clustering analysis, therefore resulting in clarification of the final rock mass rating classification systems and removal of uncertainties from the linguistic criteria. Silhouette coefficient (SC) method was used for validation k-MEANS clustering algorithm. Furthermore, for validation of FCM clustering algorithm, four validation methods including partition distribution coefficient (PC), clustering entropy (CE), Fukuyama and Sugeno (FS) and Xie and Beni index (XB) were used. It becomes clear that due to uncertainty condition on determination of rock mass rating clustering system classes, FCM clustering algorithms yields better results than k-MEANS clustering algorithm. Results of data extracted from Anomaly B of Sangan iron mines indicated that the technique used in this paper is of high importance in rock mass quality.

This paper investigates the distributed controllability of nonlocal Rayleigh beam. The mathematical problem is formulated as an abstract di, erential equation. It is shown that a sequence of eigenfunction of nonlocal Rayleigh beam forms Riesz basis. Based on Riesz basis properties and theory of abstract di, erential equation, it is proved that a vibrating nonlocal Rayleigh beam is approximately controllable under suitable distributed control force while it is not exponentially stable.

In this paper, the interaction of light with coupled metallic nanoparticles by different models are studied. To investigate nonlocal effects simple suggested model and hydrodynamic model are utilized. Metalic nanoparticles are simulated, by taking account nonlocal effects in a simple model. Therefore metal is replaced by a thin composite layer on the metal-dielectric interface. The simulation is done by finite element method. The extinction-cross section spectra of the desired structure comparison are calculated by a local, nonlocal and simple model. Nonlocal models have blue shift regarding local model, for desired structure the blue shift of the first peak in the extinction cross section spectra is 0. 19 eV. The extinction-cross section spectra of various separation distance of nanoparticles are shown. Furthermore, the influence of increasing nanoparticles radius on extinctioncross section is analyzed in details. The results reveal that by reducing nanoparticles radius or gap, surface plasmon peaks are increased, due to the stronger nonlocal response. In a smaller radius, the blue shift is significantly larger by the nonlocal model relative to the local model.