Inversion of basement relief of sedimentary basins is an important application among the non-linear modeling techniques. Particularly in sedimentary basins with hydrocarbon source potential, the thickness of sediments is one of the primary factors in determining the thermal maturation of these basins. GRAVITY methods have been vastly used to estimate the base of sedimentary basins. The aim of this research is two-dimensional modeling of the basement geometry of a sedimentary basin using the inversion of the gravimetry data. A common way to approach this problem is discretizing the basin using polygons (or other geometries), and solving the non-linear inverse problem by local optimization iteratively. This procedure provides a solution which highly depends on the initial model and the used prior information. Besides, due to the non-linearity of this inverse problem, local optimization methods will fail whenever there is no reliable initial model. The global optimization method is a promising alternative to classical inversion methods because the quality of their solutions does not depend on the initial model. Also, they do not use the derivatives of the objective function. Ant colony algorithm (ACO) is one of the kinds of important swarm intelligence algorithms which have been successfully applied in many fields such as inversion of geophysical data. This research, in two separate stages, investigates the design and implementation of the ACO as a powerful tool for two-dimensional non-linear modeling of GRAVITY data. ACO can be a substitution for the local response methods such as Marquardt-Levenberg and Gauss-Newton. To apply this algorithm in the problem under consideration, it was validated with the data obtained from a synthetic model and then, reverse modeling of the real data was performed. For evaluating the validation of this developed algorithm, it was tested by the synthetic model. Data from the synthetic models were modeled by using the developed algorithm, and acceptable results were obtained. By using this approach, the topography of the basement in the synthetic model was obtained with acceptable accuracy. In this study, the effect of ACO algorithm on different values of probable noises was investigated. The results indicate that this algorithm is suitably stable against the Gaussian white noise with relatively high amplitudes. In modeling for high noise percentage, the root mean square error of the data calculated with the original data didn't exceed 1. 64 mGal and that obtained with the original model at most was 131. 4 m. The results of modeling show acceptable agreement with the original model even in the case of data contaminated with 10% Gaussian white noise. The reliability of the proposed method to the inversion of a real GRAVITY data was confirmed by applying it on a real GRAVITY profile in the Moghan sedimentary basin. The results of this modeling are compatible with previously published works in this area.

Enhancement on the edges of the causative source is a tool in the interpretation of potential field data. There are many methods for recognizing the edges, most of which involve high pass filters based on derivatives of potential field data. In this paper, a new edge detection method is introduce, called the enhanced mathematical morphology (EMM) filter for interpretation of field data. The EMM filter uses the ratio of the erosion of the total horizontal derivative to the dilation of the total horizontal derivative to recognize the edges of the sources, and can display the edges of the bodies simultaneously. Edge detection of the potential eld data has been widely used as a signi cant tool for geophysical exploration technologies, which can delineate the horizontal locations of causative sources. Normally, various high-pass lters are used to recognize the edges of the potential eld data (Evjen 1936; Fedi and Florio 2001; Verduzco et al. 2004; Cooper and Cowan 2006; Cooper and Cowan 2011; Ma and Li 2012; Ma 2013). The EMM lter uses the ratio of the erosion of THD to the dilation of THD to recognize the edges of the source. Mathematical morphology was developed by Matheron and Serra in 1964 (SERRA, 1983); which is an image analysis and recognition tool. The structuring element (SE) is a basic operator in mathematical morphology, used to interact with an image and to draw conclusions about how a shape ts or misses the shapes in the image. SE consists of a matrix of 0s and 1s that can have any arbitrary shape and size. The basic operations of mathematical morphology are dilation and erosion. Dilation is de ned as the maximum value in the window ascertained by the SE. Erosion is de ned as the minimum value in the window ascertained by the SE. The EMM filter is expressed as (Lili et al., 2013): (, ) (, ) EMM Erosion F SE Dilation F SE  where imerode (F, SE) and imdilate (F, SE) represent the erosion and dilation of the THD, respectively. In this paper, a new relationship is presented for EMM filter that is tested on synthetic data with and without noise as well as the real potential field data in Qom salt dome. The EMM method successfully delineates the edges of the causative sources, which gives better resolution of the deeper source than other lters, and can display the edges of the bodies in a more centralized way. In this article, a new relationship is defined for the EMM filter as: (, ), ( ), ( ) 2 Dilation F SE Erosion F SE Dilation F SE EMM   The EMM filter was used to recognize the edges of the sources. It can display the edges of the shallow and deep bodies simultaneously. The EMM filter does not require the computation of vertical derivatives, which makes this method computationally stable. The EMM filter is tested on synthetic, and real potential field data in Qom salt dome and the edge detection was done with reasonable results.

In this paper, a combination of the braneworld scenario and covariant de Rham-Gabadadze-Tolley (dRGT) massive GRAVITY theory is proposed. In this setup, the Five-dimensional bulk graviton is considered to be massive. The Five dimensional nonlinear ghost-free massive GRAVITY theory affects the 3-brane dynamics and the gravitational potential on the brane. Following the solutions with spherical symmetry on the brane, the full Field equations together with the generalized Israel-Darmois junction conditions on the brane and their weak field limits are presented in details. Generally, the theory has four Stuckelberg fields along with the components of physical metric. Although analytical solutions of these equations are impossible in general, by considering some simplifying assumptions, two classes of four-dimensional spherically symmetric solutions on the brane with different background Stuckelberg fields are obtained.

Today, along with globalization, we observe economic convergence in different parts of the world. In fact, closeness of culture, race, language, religion and etc. in countries of one region, along with shorter distances and less transportation costs, have led to greater will for more cooperation among these countries. In this paper, using a GRAVITY model, the trend of bilateral trade between Iran and ECO countries is examined, and present convergence between Iran and these countries, both on the aggregate level and on the segregated sectors of different goods, is evaluated. Then, this convergence is compared with that of Iran and EURO countries. Empirical evidence shows that the bilateral trade pattern between Iran and its trade partners in ECO is a traditional one (traditional model) with an inter-industry trade structure. In addition, comparing the results of the convergence level between ECO and EURO countries shows that the rate between Iran and ECO countries is greater than that of Iran and EURO countries. The reasons can be attributed to the similar economic, social and religious structures of these countries. In addition, the results obtained from ten separated sectors show that Iran, due to superior quality of its goods, has a vertical intra- industrial trade with ECO countries in the 3 rd ,4th, 5th, 6th, 7th, 8th, 9th, and 10th groups of goods.

Distribution of thermal stresses in dams, especially concrete GRAVITY dams is a complex and significant subject in designing the dams. Although by the use of a simplified assumption, the temperature distribution along the cross section of a dam can be considered linearly, because of the low thermal diffusion coefficient for concrete and variance of atmospheric conditions with time, temperature distribution along the dam cross section is nonlinear. So, the assumption of linear distribution of temperature will not be an accurate one. A number of factors influence the temperature distribution along the dam cross section that can be divided into two groups internal factors due to hydration of cement and external factors due to atmospheric variation. The temperature distribution along the dam cross section has a significant effect on the thermal stresses.In the present paper a concrete GRAVITY dam by the use of 2D finite element analysis in a climate condition similar to Mashhad were analyzed. In this analysis concreting in hot and cold weather with different types of cements (type I and type IV) were investigated. At the first step, the results of thermal analysis were obtained and then normal stresses and displacements at different nodes were extracted. The results show that the critical stresses are produced in the case of hot weather; with high thermal hydration for cement and high expansion coefficient for the materials. These stresses in the core of a dam cross-section and away from the drainage gallery and also adjacent to the toe and heel of the dam are maximum.

The importance of the seismic behavior of concrete GRAVITY dams in their safety evaluation and stability is inevitable. Many factors affect the prediction of the behavior of concrete dams such as dam-foundation-reservoir interaction, dam and foundation cracking and also displacement due to fault movement that could causes nonlinear behavior. The aim of this study is nonlinear analysis of concrete GRAVITY dams, including displacement caused by normal fault movement in the dam foundation. For this purpose, dam-foundation-reservoir system is modeled using Lagrangian method and analysis of system is done by finite element method. The coordinate smeared crack model based on the nonlinear fracture mechanics is used for crack modeling in the dam body and foundation. Using two separate method including split node technique and contact element, the fault movement are modeled and the position and angle of fault has been studied. To verify the results, dam crest displacement and crack profile in the body of a concrete GRAVITY dam is presented as an example. The results show that low fault movement causes the cracks in the dam body and could be jeopardizes the stability and safety of concrete dam.

GRAVITY multiphase separators are one of the most important equipment in different industries. Due to the limitations related to semi-empirical models and the high-performance cost of experimental tests in finding the optimized design, computational fluid dynamics (CFD) has been widely used recently. In this research, after a total review on GRAVITY separators, a review of CFD studies on these apparatuses, to find the appropriate model for simulation and optimization, are considered. Results show that, although CFD is a powerful technique for modeling and improving the separator design, some disadvantages like using incorrect models, simplified assumptions and inappropriate optimization methods lead to inaccurate simulation and optimization results, which should be considered in future works.

The frontal of GRAVITY current is most important section of the seflow types. The advance force in front is pressure gradient due to density differences between front flow and ambient fluid. In order to find the roughness effects as a resistor on frontal velocity, a series experiment of saline GRAVITY currents were performed on rough beds with size of 0, 4, 7.5, 12 and 15 (mm). The saline GRAVITY current with three inflow discharges of 0.7, 1 and 1.3 (lit/s) and three concentrations of 10, 16, 20 (g/lit) was flowed on slope beds from 0.05 to 2.2 steep percentage. For estimation of frontal velocity and assessing effects of parameters, a linear model by correlation coefficient of 0.9 and RMSE of 0.037and mean ratio deficit of less than 10% was derived. By applying of linear modeling and linear standardization data, the efficiency index of slop, relative roughness and non-dimensional discharge (Richardson number) on prediction of non-dimension frontal velocity was estimated as 0.17, -0.50 and -0.35.

In the present study, seismic analysis of concrete GRAVITY dams strengthened by asphalt buttressing is presented for improving the seismic behavior of the Koyna dam in India subjected to Koyna ground motion. Fluid-Structure interaction is modeled including water compressibility and reservoir bottom absorption. The foundation is considered as rigid. A three-dimensional fixed smeared crack model is used to consider the nonlinear behavior of mass concrete. The analysis is carried out in the time domain by Newmark time integration scheme. Linear and nonlinear behavior of dam models subjected to horizontal and vertical components of selected record have been analysed. In order to investigate the effects of asphalt buttressing on the interface of dam and asphalt, the contact surface is defined using joint elements with a thickness of zero. The results of the analyzes confirm that the asphalt buttressing can improve the stability of the dam due to the pressure applied to the dam in counteracting the hydrostatic and hydrodynamic forces, Also the significant effect of asphalt Buttressing on the optimal distribution of stresses in the entire body of the dam as well as the prevention of stress concentration and reduction of fracture in the upper body near the dam crest show so that the crack at the lower section of the dam and at the interface of the dam and foundation is partially developed with a slower rate, and the cracking at the upper part near the crown of the dam does not spread to the upstream body of the dam and does not cause a total failure. Overall, it can be said that asphalt buttressing can improve the seismic stability of GRAVITY dams by exerting pressure on the dam in opposition to hydrostatic and hydrodynamic loads.

Inversion of GRAVITY data is one of the most interesting numerical tools for obtaining 3-D images of geological structure. In this study, modeling of GRAVITY anomalies is performed by new linear modeling Method (Compact Inversion). The principle used is to minimize the volume of causative body which is equivalent to maximizing its compactness. The anomalous density distribution is obtained using an iterative technique which is numerically stable and rapidly convergent. The principle can also be adapted to include modeling of GRAVITY anomalies by single density sources. The treatment of noise in data fits naturally into formulations of the inversion procedure. The method is illustrated by inversion of noise-free data and noisy data. The practical effectiveness of these methods is demonstrated by inversion of synthetic and real example. The real data is acquired over chromite ore in Hormozgan province of Iran. The results obtained are compared with existing outcrop and available superficial drilling.