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GGMCalc a software for calculation of the geoid undulation and the height anomaly using the iteration method, and classical gravity anomaly 总被引：1，自引：0，他引：1
The Global Geopotential Models (GGMs) are very significant because of their usefulness in determination of the parameters like geoidal undulations, height anomalies, gravity anomalies, and so on. In this paper, first, we review the calculation of such parameters and then present the GGMCalc software, which is prepared in Fortran 95 under GNU/Linux Operating System. This software is capable of using the files presented by the International Center for Global Earth Models (ICGEM) directly without need to apply any changes on them. The software is completely structural and user friendly and could be used conveniently for academic purposes. 相似文献
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A transversely isotropic material in the sense of Green is considered. Using a series of potential functions proposed in [Eskandari-Ghadi M. A complete solution of the wave equations for transversely isotropic media. J Elasticity 2005; 81:1–19], the solutions of the transient wave equations within a half-space under surface load are obtained in the Laplace–Hankel domain for axisymmetric problems. The solutions are investigated in detail in the special case of a surface point force pulse varying with time as Heaviside function. Using Cagniard–De Hoop method, the inverse Laplace transform and inverse Hankel transform of the solutions are then obtained in the form of integrals with finite limits. For validity of the analytical results, the final formulations for surface waves are degenerated for an isotropic material and compared with the existing formulation obtained by Pekeris [The seismic surface pulse. Proc Natl Acad Sci USA 1955;41:469–80], to show that they are exactly the same. The numerical evaluations of the integrals for some transversely isotropic materials as well as an isotropic one are obtained. The present approach is then numerically verified by comparing a particular case of displacements for the surface of an isotropic half-space subjected to a point load of Heaviside function with the solutions obtained by Pekeris [The seismic surface pulse. Proc Natl Acad Sci USA 1955;41:469–80]. In addition, the wave equations for the mentioned medium are obtained on the vertical line directly under the applied surface load. The final formulations are degenerated for an isotropic material and compared with the existing formulation given in Graff [Wave motion in elastic solids. New York: Dover Publications Inc; 1975 [New Ed edition, November 1991]], to show that they are also exactly the same. Then equations are presented in graphical forms using an appropriate numerical evaluation. 相似文献
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A Study on the Surface Wettability of Clastic Rocks with Potential Application for CO2 Storage Sites
Umar Bappah Adamu Gholami Raoof Raza Arshad Downey William Samuel Sarmadivaleh Mohammad Shah Afroz A. Nayak Prasanta 《Natural Resources Research》2020,29(3):2051-2061
Natural Resources Research - There have been many studies carried out in the past decades attempting to develop strategies for a safe injection of CO2 into storage sites without leakage and... 相似文献
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Leila Gholami Abdulvahed Khaledi Darvishan Ataollah Kavian 《Arabian Journal of Geosciences》2016,9(19):729
The soil conditioner in processes of soil conservation is important especially in heavily eroded areas. Because in this study done in Educational and Research Forest Watershed of Tarbiat Modares University, north of Iran, the experiments created four treatments of control and different wood chips with rates of 0.5, 1, and 1.5 kg m?2, by rainfall simulation in rainfall intensity of 60 mm h?1, and plot scale of 1 m2 on changing ponding time, runoff coefficient, sediment concentration, and soil loss. The results showed that the average change ponding time in control treatment and wood chip treatments with rates of 0.5, 1, and 1.5 kg m?2 were 4.25, 7.48, 11.63, and 12.45 min. Also, the average change runoff coefficient in control treatment and wood chip treatments with rates of 0.5, 1, and 1.5 kg m?2 were 50.03, 26.27, 15.28, and 13.17 %. The results also indicated that the wood chips could decrease average soil loss with the rates of ?52.15, ?82.18, and ?89.35 % compared with control treatment for 0.5, 1, and 1.5 kg m?2 of wood chips, respectively. The one-way ANOVA results showed that the runoff coefficient, sediment concentration, and soil loss decreased with increasing wood chip amount, and the effect of conservation treatment was significant on study variables (R 2 = 0.99). But, the ponding time increased with increasing wood chip amount, and this effect was significant on study variables (R 2 = 0.99). 相似文献
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Specification and prediction of nickel mobilization using artificial intelligence methods 总被引：1，自引：0，他引：1
Raoof Gholami Mansour Ziaii Faramarz Doulati Ardejani Shahoo Maleki 《Central European Journal of Geosciences》2011,3(4):375-384
Groundwater and soil pollution from pyrite oxidation, acid mine drainage generation, and release and transport of toxic metals are common environmental problems associated with the mining industry. Nickel is one toxic metal considered to be a key pollutant in some mining setting; to date, its formation mechanism has not yet been fully evaluated. The goals of this study are 1) to describe the process of nickel mobilization in waste dumps by introducing a novel conceptual model, and 2) to predict nickel concentration using two algorithms, namely the support vector machine (SVM) and the general regression neural network (GRNN). The results obtained from this study have shown that considerable amount of nickel concentration can be arrived into the water flow system during the oxidation of pyrite and subsequent Acid Drainage (AMD) generation. It was concluded that pyrite, water, and oxygen are the most important factors for nickel pollution generation while pH condition, SO4, HCO3, TDS, EC, Mg, Fe, Zn, and Cu are measured quantities playing significant role in nickel mobilization. SVM and GRNN have predicted nickel concentration with a high degree of accuracy. Hence, SVM and GRNN can be considered as appropriate tools for environmental risk assessment. 相似文献
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Landsat Thematic Mapper (TM) digital data acquired in the fall of 1988 and digital elevation model (DEM) data were evaluated for use in characterizing the spatial distribution of defoliation conditions within the boreal montane spruce‐fir ecosystem in the Black Mountains (Mtns.) of North Carolina. Correlation coefficients between the TM waveband data and field estimates of defoliation taken from 22 one hectare field plots were low (0.10 to ‐0.54). TM band four (near infrared) was the only waveband found to be significantly correlated with needle loss. Defoliation was also shown to be significantly correlated with digital elevation and aspect data. A multivariate linear regression model predicting percent defoliation was developed from the TM, elevation, and aspect data for the 21 field plots. In addition to having a high R2(0.85) the model was shown to reliably predict defoliation conditions throughout the ecosystem. A color‐coded classified image depicting the spatial distribution of defoliation conditions within the study site was generated by applying the model to the TM and DEM data. 相似文献
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Raoof Gholami Vamegh Rasouli Andisheh Alimoradi 《Rock Mechanics and Rock Engineering》2013,46(5):1199-1209
Rock mass classification systems such as rock mass rating (RMR) are very reliable means to provide information about the quality of rocks surrounding a structure as well as to propose suitable support systems for unstable regions. Many correlations have been proposed to relate measured quantities such as wave velocity to rock mass classification systems to limit the associated time and cost of conducting the sampling and mechanical tests conventionally used to calculate RMR values. However, these empirical correlations have been found to be unreliable, as they usually overestimate or underestimate the RMR value. The aim of this paper is to compare the results of RMR classification obtained from the use of empirical correlations versus machine-learning methodologies based on artificial intelligence algorithms. The proposed methods were verified based on two case studies located in northern Iran. Relevance vector regression (RVR) and support vector regression (SVR), as two robust machine-learning methodologies, were used to predict the RMR for tunnel host rocks. RMR values already obtained by sampling and site investigation at one tunnel were taken into account as the output of the artificial networks during training and testing phases. The results reveal that use of empirical correlations overestimates the predicted RMR values. RVR and SVR, however, showed more reliable results, and are therefore suggested for use in RMR classification for design purposes of rock structures. 相似文献