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Recently, groundwater vulnerability assessment of coastal aquifers using the GALDIT framework has been widely used to investigate the process of groundwater contamination. This study proposes multi-attribute decision-making (MADM) entropy and Wilcoxon non-parametric statistical test methods to improve the vulnerability index of coastal aquifers. The rates and weights of this framework were modified using Wilcoxon non-parametric and entropy methods, respectively, and a combined framework of GALDIT-entropy, Wilcoxon-GALDIT, and Wilcoxon-entropy was obtained. Pearson correlation coefficients between the mentioned vulnerability indices and total-dissolved solids (TDS) of 0.51, 0.66 and 0.75, respectively, were obtained. According to the results, the Wilcoxon-entropy index had the highest correlation with TDS. Generally, it can be concluded that the proposed frameworks provide a more accurate estimation of vulnerability distribution in coastal aquifers. 相似文献
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Mechanical Behavior of a Clay Soil Reinforced with Nylon Fibers 总被引：2，自引：1，他引：1
A. R. Estabragh A. T. Bordbar A. A. Javadi 《Geotechnical and Geological Engineering》2011,29(5):899-908
Soft soils are well known for their low strength and high compressibility. Several techniques, including reinforcement, are
commonly used to increase the strength and decrease the deformation of this kind of soil. This paper presents the results
of an investigation into the effects of fiber on the consolidation and shear strength behavior of a clay soil reinforced with
nylon fibers. A series of one dimensional consolidation and triaxial tests were conducted on samples of unreinforced and reinforced
clay with different percentages of randomly distributed nylon fibers. The results show that the preconsolidation pressure
decreases and the coefficient of swelling and compression generally increase with increasing the fiber content. Furthermore,
the addition of the fiber leads to a significant increase in shear strength and friction angle of the natural soil. 相似文献
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Finite temperature calculations for the bulk properties of a strange star using a many-body approach
We have considered a hot strange star matter, just after the collapse of a supernova, as a composition of strange, up and
down quarks to calculate the bulk properties of this system at finite temperature with the density dependent bag constant.
To parameterize the density dependent bag constant, we use our results for the lowest-order constrained variational (LOCV)
calculations of asymmetric nuclear matter. Our calculations for the structure properties of the strange star at different
temperatures indicate that its maximum mass decreases by increasing the temperature. We have also compared our results with
those of a fixed value of the bag constant. It can be seen that the density-dependent bag constant leads to higher values
of the maximum mass and radius for the strange star. 相似文献
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We have considered a hot neutron star with a quark core,a mixed phase of quark-hadron matter,and a hadronic matter crust and have determined the equation of state of the hadronic phase and the quark phase.We have then found the equation of state of the mixed phase under the Gibbs conditions.Finally,we have computed the structure of a hot neutron star with a quark core and compared our results with those of the neutron star without a quark core.For the quark matter calculations,we have used the MIT bag model... 相似文献
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A. R. Estabragh A. T. Bordbar A. A. Javadi 《Geotechnical and Geological Engineering》2013,31(2):501-510
This paper presents the results of an experimental investigation into the effects of discrete palm fibers on the consolidation and shear behavior of a randomly reinforced clay soil. Three groups of reinforced soil samples were prepared at three different fiber contents (10, 20 and 30 %). Consolidation and triaxial tests were carried out on the samples. The results indicate that the inclusion of the fiber reinforcement within the soil causes decrease in preconsolidation pressure and increase in compressibility and swelling indices. In addition, the strength and friction angle increase considerably in terms of total and effective stresses. The results also show that the increase in the slope of the critical state line in $ q :p^{\prime } $ space is a function of fiber content. 相似文献
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We have calculated some properties of spin polarized strange quark matter(SQM) in a strong magnetic field at zero temperature using the MIT bag model.We showed that the equation of state of spin polarized SQM is stiffer than that for unpolarized cases.We have also computed the structural properties of a spin polarized strange quark star(SQS) and found that the presence of a magnetic field leads to a more stable SQS when compared to the structural properties of an unpolarized SQS. 相似文献
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We have calculated the equation of state of the neutron star matter and some of its properties for a wide range of nucleon-nucleon
potentials using the lowest order constrained variational (LOCV) method. It turns out that for the UV
14+TNI potential, the proton fraction exhibits a peak and falls off at high densities. The equation of state with the UV
14+TNI potential is seen to be much harder than those with other potentials. The polytropic behaviour of the neutron star matter
with various potentials are discussed. Compared with the other methods, the LOCV results show good agreement for densities
below 0.7 fm
-3. Above this density, however, the differences with other methods are appreciable. 相似文献