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71.
72.
Artificial neural networks have a wide application in many areas of science and engineering and, particularly, in geotechnical
problems with some degree of success due to the fact that the mechanical behavior of rocks are not salient. They are highly
nonlinear, quite complex and complicated. While applying neural network in such complicated problems, epoch determination
is based on hit-and-trail basis mainly. In this paper, the effect of different number of epochs is shown on the network and
a method is proposed to determine the optimum number of epoch with the help of self-organized map (SOM) to avoid overtraining
of the network. Data distribution is also done with the help of SOM and a statistical analysis is made to show consistency
between training and testing dataset for ensuring the optimal model performance. 相似文献
73.
A. M. Swinbank A. C. Edge Ian Smail J. P. Stott M. Bremer Y. Sato C. van Breukelen M. Jarvis I. Waddington L. Clewley J. Bergeron G. Cotter S. Dye J. E. Geach E. Gonzalez-Solares P. Hirst R. J. Ivison S. Rawlings C. Simpson G. P. Smith A. Verma T. Yamada 《Monthly notices of the Royal Astronomical Society》2007,379(4):1343-1351
74.
75.
Sardana Sahil Sinha Rabindra Kumar Verma A. K. Jaswal Mamta Singh T. N. 《Geotechnical and Geological Engineering》2022,40(11):5507-5525
Geotechnical and Geological Engineering - The Lengpui-Aizawl highway in the Northeastern part of India has witnessed several rockfall events in the past decades. This is the only highway that... 相似文献
76.
Ankam Durga Prasad Lori Rastogi Vinod Kumar Verma Vasudevan Krishna Kumari Sudhakar Yadlapalli Kulamani Dash 《Geostandards and Geoanalytical Research》2023,47(3):629-636
The National Centre for Compositional Characterisation of Materials (NCCCM) / Bhabha Atomic Research Centre (BARC) and National Aluminium Company Limited (NALCO), India have produced an Indian origin bauxite certified reference material (CRM), referred to as BARC-B1201, certified for major (Al2O3, Fe2O3, SiO2, TiO2, loss on ignition - LOI) and trace contents (V2O5, MnO, Cr2O3, MgO). Characterisation was undertaken by strict adherence to ISO Guides. A method previously developed and validated in our laboratory, using single step bauxite dissolution and subsequent quantitation (of Al2O3, Fe2O3, SiO2, TiO2, V2O5, MnO, Cr2O3 and MgO) by ICP-AES (SSBD ICP-AES) was used for homogeneity studies and an inter-laboratory comparison exercise (ILCE) of the candidate CRM. LOI was determined by thermo-gravimetric analysis. Property values were assigned after an ILCE with participation from seventeen reputed government and private sector laboratories in India. The CRM was certified for nine property values: Al2O3, Fe2O3, SiO2, TiO2, V2O5, MnO, Cr2O3, MgO and LOI, which are traceable to SI units. 相似文献
77.
Assessment of tunnel instability—a numerical approach 总被引:2,自引:1,他引:1
This paper outlines the application of numerical modeling to predict deformation and stability of tunnel to be excavated in Bansagar, M.P., India. To meet the ever-increasing demand of transportation, energy, and other infrastructure projects, a large volume of rock tunneling is being carried out throughout the world. The geotechnical properties along the route of the 1,800-m long tunnel in the Bansagar region of India have been studied. The rock mass rating and rock mass quality systems were employed for empirical rock mass quality determination. Numerical analysis for the stress–strain distribution of the tunnel excavation and support systems was also carried out. In order to simulate the excavation of tunnel (NATM) at a depth of 150 m below the ground , a series of finite element analyses using Mohr-coulomb elasto-plastic constitutive model has been carried out using PLAXIS 2D. The stability of tunnel has been analyzed, and stress pattern have been discussed. 相似文献
78.
The Aravalli mountain range (AMR) in the northwestern part of the Indian Peninsula consists of two main Proterozoic metasedimentary and metaigneous sequences, the Aravalli and Delhi Supergroups, respectively, which rest over the Archaean gneissic basement. A synthesis and reinterpretation of the available geological, geochronological and geophysical data, including results of own field work and geophysical interpretations pertaining to the AMR, indicate its origin as an inverted basin: rifting into granitoid basement began ca. 2.5; Ga ago with Aravalli passive rifting (ca. 2.5–2.0 Ga) and Delhi active rifting (ca. 1.9–1.6 Ga). Associated mafic igneous rocks show both continental and oceanic tholeiitic geochemistry and are comparable with Phanerozoic, rift-related magmatic products. Available data showed no conclusive evidence for oceanic lithoshere and island-arc/active margin magmatic activity in the AMR. Subsequent inversion and orogeny (Delhi orogeny, ca. 1.5-1.4 Ga) lead to complex deformation and metamorphism. Only in the western and central zones has the basement been involved in this mid-Proterozoic (Delhi) deformation, whereas it is unaffected in the eastern part, except for local shear zones mainly along the basement/cover interface. The grade of metamorphism increases from the greenschist facies in the east to the amphibolite facies in the west with local HP assemblages. These latter are explained by rapid burial and exhumation of thin and cool continental lithosphere. Subsequently, during a final, mild phase of inversion, the Vindhyan basins consisting mainly of sandstones, limestones and shales, flanking the AMR formed which are comparable to foreland basins. The tectonic evolution of the AMR is therefore interpreted as an example of a major inverted continental rift and of a Proterozoic intra-continental orogen. 相似文献
79.
Summary The object of the present paper is to investigate the propagation of surface waves on a non-homogeneous aeolotropic cylindrical shell surrounded by vacuum. The elastic constantsc
ij
(i, j=1,2...) and density of the material of the shell are assumed to be of the form
and
respectively, where ij, 0 are constants andk
1,k
2 are any integers. 相似文献
80.