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Cryptosystem for Meshed 3D through Cellular Automata
Published in Ali Ahmadian, Soheil Salahshour, Soft Computing Approach for Mathematical Modeling of Engineering Problems, 2021
R. Sulaiman, M.A. Al-Jabbar, A. Ahmadian, A.M.A. Abdalla
A texture map is a bitmap image or a procedural design mapped to the surface of a shape or polygon and can be stored in common image file formats. It was pioneered by Edwin Catmull in 1974. A textured object needs to include a texture map (also known as texture coordinates, UV map or UV coordinates) to lay a 2D image on the 3D surface effectively. The locations of vertices and faces of the 3D object are defined with 3D-coordinates, where a UV map projects the locations of those vertices and faces onto the 2D plane. UV-axes are used to express the vertical and horizontal axes of the texture space, and to reduce opacity along the x-axis and y-axis, which correspond to the geometry coordinates of the 3D object. Therefore, working with UV-coordinates allows automatic or manual adjustment of the mapping coordinates without changing the 3D object. The UV map must be taken into consideration when performing encryption because it must be transmitted with the encrypted object and its textured image, and this may undermine its security (Segal et al. 1992; Malzbender et al. 2001).
R
Published in Phillip A. Laplante, Dictionary of Computer Science, Engineering, and Technology, 2017
raster an array of scanlines, painted across a CRT screen, which taken together form a rectangular 2D image. Often the term raster is used to refer to the 2D array of pixel values stored digitally in a frame buffer.
Blasting damage of double cylindrical charges based on fractal theory
Published in Mechanics of Advanced Materials and Structures, 2023
Chenglong Xiao, Renshu Yang, Chenxi Ding, Yuanyuan You, Zhen Liu, Feixiang Lu
After the experiment, the images are imported into the VIC-2D digital image processing software. The image before detonation is used as the reference image for data processing, and the area on the cylindrical charge’s right side is chosen as the calculation area. Figure 7 shows the evolvement of the horizontal strain εx on the specimen’s surface after explosive initiation. In this image, the horizontal direction to the right corresponds to the positive x-axis direction, while the vertical direction up corresponds to the positive y-axis direction. Red and orange represent the specimen surface tension, whereas blue and purple represent the specimen surface compression. The time t of explosive initiation is set to 0 μs. The cylindrical charge’s right side is compressed following detonation. The compressive strain zone expands to the specimen’s upper right with explosive detonation. At t = 46.67 μs, the compressive strain zone on the explosive’s right side transforms gradually into a tensile strain zone.
Evaluation of the airport runway flexible pavement macro-texture using digital image processing technique (DIPT)
Published in International Journal of Pavement Engineering, 2022
Omid Ghaderi, Mohammad Abedini
Due to the importance of adequate macro-texture of pavement's surfaces for maintaining key parameters of safety such as friction and skid resistance especially in high-speed conditions of vehicle braking, it is important to monitor and evaluate the macro-texture condition in proper time intervals for making a decision in the pavement management system (PMS) and preventing possible crashes. Non-contact devices for texture evaluation are often heavy, small scanned area, more sensitive to inhomogeneity and cracks in surface pavement and more importantly they cannot capture the concave recesses of the pavement surface (ASTM International 2015c, 2015a). We chose sand patch test that is more suitable for a big field study with various pavement mixtures. In this study, the main goal is to compare different 2D digital image processing techniques for finding feasible and reliable methods for the evaluation of pavement surface macro-texture instead of the accurate but time-consuming and sensitive conventional sand patch test (SPT). For this reason, three different digital image processing was utilised on 2D images of pavement surfaces. First, these three methods were compared visually for sample texture images. The obtained results from each method were compared with Mean Texture Depth (MTD) data derived from the sand patch test that was conducted on the same points using statistical analysis. Regression models for each method were presented as well, and methods with high accuracy and precision for pavement macro-texture evaluation were suggested.
Extraction and analysis of microscopic traffic data in disordered heterogeneous traffic conditions
Published in Transportation Letters, 2021
R. B. Amrutsamanvar, B. R. Muthurajan, L. D. Vanajakshi
where and , are the non-square pixel scaling factor in and -direction, respectively. and are the offset between the 2D points of the image plane and the 2D points of the digital image in the and direction, respectively. is the focal length of the camera, and are the parameters in pixel/m units. The distance of the point from the center of aperture is denoted by . This process of projective transformation is nonlinear in the Euclidean reference system . In order to obtain a linear equation for projective transformation, the Euclidean reference system needs to be changed to a homogeneous reference system . The transformation from Euclidean to a Homogeneous reference system () is applied to obtain the equation of projective transform (Hartley and Zisserman 2003; The OpenCV Reference Manual, 2014) as shown in Equation (2).