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1.
In this paper, we introduce new sets of 2D and 3D rotation, scaling and translation invariants based on orthogonal radial Racah moments. We also provide theoretical mathematics to derive them. Thus, this work proposes in the first case a new 2D radial Racah moments based on polar representation of an object by one-dimensional orthogonal discrete Racah polynomials on non-uniform lattice, and a circular function. In the second case, we present new 3D radial Racah moments using a spherical representation of volumetric image by one-dimensional orthogonal discrete Racah polynomials and a spherical function. Further 2D and 3D invariants are extracted from the proposed 2D and 3D radial Racah moments respectively will appear in the third case. To validate the proposed approach, we have resolved three problems. The 2D/ 3D image reconstruction, the invariance of 2D/3D rotation, scaling and translation, and the pattern recognition. The result of experiments show that the Racah moments have done better than the Krawtchouk moments, with and without noise. Simultaneously, the mentioned reconstruction converges rapidly to the original image using 2D and 3D radial Racah moments, and the test 2D/3D images are clearly recognized from a set of images that are available in COIL-20 database for 2D image, and PSB database for 3D image.  相似文献   
2.
In this study, the DASTI method was used to evaluate vulnerability to groundwater pollution in the vicinity of Rabat, western Morocco. The model is based on the characterization of five intrinsic parameters: unsaturated zone thickness, saturated zone thickness and lithology, soil texture, topography and hydraulic gradient. A system of classes of the hydrogeological characteristics was applied to evaluate relative vulnerability to groundwater contamination and a susceptibility map was prepared based on land use and the vulnerability index map. The study showed the DASTI method (applied using IDRISI software) can serve as a tool to evaluate vulnerability to pollution and thus facilitate programs to protect groundwater resources. An erratum to this article can be found at  相似文献   
3.
The Kettara site (Morocco) is an abandoned pyrrhotite ore mine in a semi-arid environment. The site contains more than 3 million tons of mine waste that were deposited on the surface without concern for environmental consequences. Tailings were stockpiled in a pond, in a dyke, and in piles over an area of approximately 16?ha and have generated acid mine drainage (AMD) for more than 29?years. Geophysical methods have been used at the Kettara mine site to determine the nature of the geological substrate of the tailings pond, the internal structure of the mine wastes, and to investigate the pollution zones associated with sulphide waste dumps. Electrical resistivity tomography (ERT) and seismic refraction data were acquired, processed, and interpreted; the results from ERT and seismic refraction were complementary. A topographical survey of the tailings disposal area was also undertaken to estimate the volume of wastes and quantify the AMD process. Two-dimensional inverse models were used to investigate the geophysical data and indicated alteration zones at depth. It was determined that the material could be classified into three categories: tailings, with low resistivity (5?C15??? m) and low velocity (500?C1,800?m/s); altered, black shales, with intermediate resistivity (20?C60??? m) and velocity (2,000?C3,500?m/s), and; materials with high resistivity and velocity (>60????m and >4,000?m/s, respectively), including unaltered shales associated with quartzite seams. The low-resistivity zone generates AMD, which migrates downward through fractures and micro-fractures. The substrate is composed of broken and altered shale, which facilitates AMD infiltration.  相似文献   
4.
The heterogeneous Plio-Quaternary coastal aquifer of the Mamora Basin is the most significant reservoir of Morocco. It is composed of sandstones, conglomerates, limestones and more or less argillaceous sands. The increase in the requirements for water in this area requires further information on the relations between the geometry of the aquifer and the salinity of the water. A hydrochemical analysis was undertaken and highlighted three zones of high mineralization. A geophysical approach allowed the determination of the principal aquifer levels, the localization of the various types of water (fresh, brackish and salt) and the geometry of the aquifer base. The results obtained by these two approaches provide a better image of the phenomena governing the groundwater flows and their interactions   相似文献   
5.

In this work, we propose new sets of 2D and 3D rotation invariants based on orthogonal radial dual Hahn moments, which are orthogonal on a non-uniform lattice. We also present theoretical mathematics to derive them. Thus, this paper presents in the first case new 2D radial dual Hahn moments based on polar representation of an image by one-dimensional orthogonal discrete dual Hahn polynomials and a circular function. The dual Hahn polynomials are general case of Tchebichef and Krawtchouk polynomials. In the second case, we introduce new 3D radial dual Hahn moments employing a spherical representation of volumetric image by one-dimensional orthogonal discrete dual Hahn polynomials and a spherical function, which are orthogonal on a non-uniform lattice. The 2D and 3D rotational invariants are extracts from the proposed 2D and 3D radial dual Hahn moments respectively. In order to test the proposed approach, three problems namely image reconstruction, rotational invariance and pattern recognition are attempted using the proposed moments. The result of experiments shows that the radial dual Hahn moments have performed better than the radial Tchebichef and Krawtchouk moments, with and without noise. Simultaneously, the mentioned reconstruction converges quickly to the original image using 2D and 3D radial dual Hahn moments, and the test images are clearly recognized from a set of images that are available in COIL-20 database for 2D image and PSB database for 3D image.

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6.
In this paper, we propose a new set of 2D and 3D rotation invariants based on orthogonal radial Meixner moments. We also present a theoretical mathematics to derive them. Hence, this paper introduces in the first case a new 2D radial Meixner moments based on polar representation of an object by a one-dimensional orthogonal discrete Meixner polynomials and a circular function. In the second case, we present a new 3D radial Meixner moments using a spherical representation of volumetric image by a one-dimensional orthogonal discrete Meixner polynomials and a spherical function. Further 2D and 3D rotational invariants are derived from the proposed 2D and 3D radial Meixner moments respectively. In order to prove the proposed approach, three issues are resolved mainly image reconstruction, rotational invariance and pattern recognition. The result of experiments prove that the Meixner moments have done better than the Krawtchouk moments with and without nose. Simultaneously, the reconstructed volumetric image converges quickly to the original image using 2D and 3D radial Meixner moments and the test images are clearly recognized from a set of images that are available in a PSB database.  相似文献   
7.
Multimedia Tools and Applications - This study focuses on the question of the stability analysis of complex interconnected nonlinear systems using the property of Lyapunov and Finsler. The main...  相似文献   
8.
9.
The dye‐sensitized solar cell (DSSC) provides a clean, renewable, and cheap energy source. Since the beginning of the 1990s, DSSC has seen enormous development because of an increase in world energy consumption and the concerns about the environmental impact associated with combustion of fossil fuels. However, the efficiency of the DSSC to be a competitive energy source has not been achieved. In this work, we analyzed the effect of various materials parameters and environmental conditions on the performance of DSSC. To maintain the optimum performance for DSSCs and to enhance the energy and exergy efficiency in practical application environments, it is recommended to have the porous thin film TiO2 at porosity of 0.40, thin film thickness of porous TiO2 at 0.0005 cm, thickness of redox electrolyte at 0.0002 cm, diffusion coefficient of 0.0002 cm2 s?1, electron diffusion length of 0.0013 cm, and operating temperature of 300 K with light intensity of 100 mW cm?2. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
10.
The property of rotation, scaling and translation invariant has a great important in 3D image classification and recognition. Tchebichef moments as a classical orthogonal moment have been widely used in image analysis and recognition. Since Tchebichef moments are represented in Cartesian coordinate, the rotation invariance can’t easy to realize. In this paper, we propose a new set of 3D rotation scaling and translation invariance of radial Tchebichef moments. We also present a theoretical mathematics to derive them. Hence, this paper we present a new 3D radial Tchebichef moments using a spherical representation of volumetric image by a one-dimensional orthogonal discrete Tchebichef polynomials and a spherical function. They have better image reconstruction performance, lower information redundancy and higher noise robustness than the existing radial orthogonal moments. At last, a mathematical framework for obtaining the rotation, scaling and translation invariants of these two types of Tchebichef moments is provided. Theoretical and experimental results show the superiority of the proposed methods in terms of image reconstruction capability and invariant recognition accuracy under both noisy and noise-free conditions. The result of experiments prove that the Tchebichef moments have done better than the Krawtchouk moments with and without noise. Simultaneously, the reconstructed 3D image converges quickly to the original image using 3D radial Tchebichef moments and the test images are clearly recognized from a set of images that are available in a PSB database.  相似文献   
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