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Nagpal Anushree Hassan Mohammad Siddiqui Masood Ahsan Tajdar Atiqua Hashim Mohammad Singh Abhra Gaur Suman 《GeoJournal》2021,86(2):649-661
GeoJournal - Sanitation is a multidimensional concept alluding primarily to provision of services for safe disposal of human excreta, provision of clean potable water as well as maintenance of... 相似文献
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Ring foundation on elastic subgrade: an analytical solution for computer modelling using the Lagrangian multiplier method 
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下载免费PDF全文 In the practice of geotechnical engineering, the case of a ring footing carrying a set of concentrated point loads is a common problem. At times, the induced vertical and angular displacements for the ring footing need to be evaluated at a relatively precise level. By making use of the governing set of equations derived for the case of a general curved beam, expressions that can be easily implemented in modern computing software are derived for the vertical and angular displacements of a ring footing of rectangular cross section as functions of the radial position. The loading case considered is a vertical point load, and the soil is modelled as elastic. Estimates of the displacements have been shown for a common range of practical applications. The behaviour for a set of concentrated loads may be evaluated using the derived equations through direct superposition. Nonlinear finite element analysis is used to evaluate the vertical deflection and angular twist of the ring foundation. Numerical analysis performed for three ring foundations with different radii and cross sections is reported to validate the accuracy of the derived analytical solution. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
3.
Naseer Iqbal Tabasum Masood Mubashir Hamid Naveel Ahmad Bari Maqbool 《Astrophysics and Space Science》2014,353(2):621-624
The correlation function theory on the basis of prescribed boundary conditions provides a deeper understanding in studying the dynamical parameters of galaxy clusters. The approach approximates that the moderate dense systems discussed by a two point correlation function is helpful for describing the dynamical nature of galaxy clusters. The projected theory of two point correlation function for point mass and extended mass structures can be used an alternative tool in measuring the average peculiar motion and temperature profile of galaxy clusters. 相似文献
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The coupling of Shukla-Varma (SV) and convective cell modes is discussed in the presence of non-Boltzmannian electron response and parallel equilibrium shear flow. In the linear case, a new dispersion relation is derived and analyzed. It is found that the coupled SV and convective cell modes destabilize in the presence of electron shear flow. On the other hand, in the nonlinear regime, it is shown that Shukla-Varma mode driven counter rotating vortices can be formed for the system under consideration. It is found that these vortices move slowly by comparison with the ion acoustic or electron drift-wave driven counter rotating vortices. The relevance of the present investigation with regard to space plasmas is also pointed out. 相似文献
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Hydrochemical investigation and quality assessment of ground water in rural areas of Delhi,India 总被引：1，自引：0，他引：1
The suitability of groundwater quality for drinking and agricultural purposes was assessed in the rural areas of Delhi based
on the various water quality parameters. A total of 50 ground water samples were collected randomly from different sources
viz. hand pump, tube well, boring and analyzed for major ion chemistry to understand the operating mechanism of geochemical
processes for ground water quality. The quality analysis is performed through the estimation of pH, EC, TDS, total hardness,
total alkalinity, Na, K, Cl, NO3, SO4, DO, BOD, Cu, Cr, Cd, Ni, Zn and Pb. Hydrochemical facies were identified using Piper, Durov and Chadha diagram. Chemical
data were also used for mathematical calculations (SAR, %Na, RSC, PI, KI, and chloroalkaline indices) for better understanding
the suitability of ground water for irrigation purposes. The results of saturation index shows that all the water samples
were supersaturated to undersaturated with respect to carbonate minerals and undersaturated with respect to sulphate and chloride
minerals. According to USSL diagram, most of the samples fall in the field of C3S1, indicating medium salinity and low sodium water which can be used for almost all types of soil with little danger of exchangeable
sodium. Assessment of water samples from various methods indicated that majority of the ground water in the study area is
chemically suitable for drinking and agricultural uses. 相似文献
7.
Nonlinear properties of the quantum magnetoacoustic wave are studied in electron-ion magnetoplasmas. In this regard, cylindrical Korteweg deVries (CKdV) equation is derived for small amplitude perturbations. The solution of the planar KdV equation is obtained using the tanh method and is subsequently used as an initial profile to solve the CKdV equation. It is found that the system under consideration admits compressive solitary structures. Finally, it is found that the amplitude as well as the width of the nonplanar magnetosonic solitary structure increases with the increase in the magnetic field whereas a decrease is observed with the increase in number density of the system. The present study may be beneficial to understand the nonlinear wave propagation in nonplanar geometries in dense plasmas. 相似文献
8.
Linear and nonlinear propagation of dust drift waves are investigated in the presence of Cairns and Kappa distributed ion population and Boltzmannian electrons. It is found the frequency of the dust drift wave is greatest for the Cairns, intermediate for Kappa and the least for the Maxwellian distributed ions. Using the drift approximation, a nonlinear equation is derived for the dust drift shock waves which reduces to a Korteweg-de Vries-Burgers (KdVB)-like equation in the comoving frame of reference. The solution of the KdVB-like equation is obtained using the tanh method. It is found that the non-Maxwellian ion population, dust neutral collision frequency as well as the inverse dust density scale length inhomogeneity alter the propagation characteristics of the nonlinear dust drift shock waves. Interestingly, it is found that the non-Maxwellian ion population modifies the scale lengths over which the nonlinear structures are formed. The work presented here may be useful to understand the low frequency electrostatic shock waves in inhomogeneous dusty plasmas such as those found in planetary environments. 相似文献
9.
The impact of Southern Oscillation on thecyclogenesis over the Bay of Bengal duringthe summer monsoon has been investigated.The analysis of correlation coefficients(CCs) between the frequency of monsoondepressions and the Southern OscillationIndex (SOI) reveals that more depressionsform during July and August of El Niñoyears. Due to this, the seasonal frequencyof monsoon depressions remains little higherduring El Niño epochs even though thecorrelations for June and September are notsignificant. The CCs for July and August aresignificant at the 99% level.The El Niño-Southern Oscillation (ENSO)is known to affect Indian MonsoonRainfall (IMR) adversely. The enhancedcyclogenesis over the Bay of Bengal duringJuly and August is an impact of ENSO whichneeds to be examined closely. Increasedcyclogenesis over the Bay of Bengal may bereducing the deficiency in IMR duringEl Niño years by producing more rainfallover the eastern parts of India duringJuly and August. Thus there is a considerablespatial variation in the impact of ENSOon the monsoon rainfall over India and El Niñoneed not necessarily imply a monsoonfailure everywhere in India.The area of formation of monsoon depressionsshifts eastward during El Niño years.Warmer sea surface temperature (SST) anomaliesprevail over northwest and adjoiningwestcentral Bay of Bengal during premonsoon andmonsoon seasons of El Niño years.May minus March SOI can provide useful predictionsof monsoon depression frequencyduring July and August. 相似文献
10.
Obliquely propagating nonlinear structures in dense dissipative electron positron ion magnetoplasmas
Nonlinear electrostatic waves in dense dissipative magnetized electron-positron-ion (e-p-i) plasmas are investigated employing
the quantum hydrodynamic model. In this regard, Zakharov Kuznetsov Burgers (ZKB) equation is derived in dense plasmas using
the small amplitude perturbation expansion method. It is observed that obliqueness, positron concentration, kinematic viscosity,
and the ambient magnetic field significantly alter the structure of nonlinear quantum ion acoustic waves in dense dissipative
e-p-i magnetoplasmas. The present study may be useful to understand the nonlinear propagation characteristics of electrostatic
shock structures in dense astrophysical systems where the quantum effects are expected to dominate. 相似文献