Enhancement of Dry Beneficiation of Coal by Air Distributor Design Modification in an Air-Pulsated Stratifier     

Sahoo  Monica  Kumar  Abhishek  Chalavadi  Ganesh  Gupta  Ambesh  Singh  Ranjeet K. 《Natural Resources Research》2021,30(5):3643-3658

Natural Resources Research - This study investigated the segregation of organic (maceral) and inorganic (mineral matter or ash) contents of coal in an air stratifier after design modification in...  相似文献   

The Interannual variability of rainfall over homogeneous regions of Indian summer monsoon     

Sahoo  Monalisa  Kumar Yadav  Ramesh 《Theoretical and Applied Climatology》2022,148(3-4):1303-1316

Theoretical and Applied Climatology - The Indian subcontinent, due to its enormous variety of geographical features, is associated with inhomogeneity. Hence, in the present study, we have...  相似文献   

Direct Numerical Simulation of a Turbulent Channel Flow with Forchheimer Drag     

Bhattacharjee  Soumak  Mortikov  Evgeny  Debolskiy  Andrey  Kadantsev  Evgeny  Pandit  Rahul  Vesala  Timo  Sahoo  Ganapati 《Boundary-Layer Meteorology》2022,185(2):259-276

Boundary-Layer Meteorology - We characterize the turbulent flow, using direct numerical simulations (DNS), within a closed channel between two parallel walls with a canopy of constant areal density...  相似文献   

Hydrogeochemical evolution and potability evaluation of saline contaminated coastal aquifer system of Rajnagar,Odisha, India: A geospatial perspective     

P P Das  H K Sahoo  P P Mohapatra 《Journal of Earth System Science》2016,125(6):1157-1174

The present article reports the results of a comprehensive hydrogeochemical study carried out across the coastal aquifer system of Rajnagar block, Kendrapara district, Odisha, India. The research involved collection of representative groundwater samples during the pre- and post-monsoon seasons with in situ as well as laboratory measurement of various hydrogeochemical variables. Analysis of the subsurface water samples portrays an alkali dominated water type during the pre-monsoon season whereas alkaline earth has a significantly increased influence during the post-monsoon period. However, the aquifer system displays an even distribution of strong and weak acids for both the monsoonal regimes. The hydrogeochemistry is controlled by aquifer lithology with a general occurrence of ion exchange and acid–base reaction processes across the study area. Spatial disposition of major cations indicates freshening of this coastal aquifer system in S–N and SW–NE directions. Potability analysis of the samples is suggestive of widespread unsuitability for domestic, agriculture and industrial uses. The extensive occurrence of salinity hazards, sodium hazards and magnesium hazards across the terrain makes the groundwater unsafe for domestic and agricultural utilization while industrial potability analysis suggests the aquifer system is moderately corrosive but non-incrusting. Post-monsoon however, the subsurface waters display a general decrease in hazardous nature with increased suitability for various uses.  相似文献   

Development of rational models for tunnel blast prediction based on a parametric study   总被引：2，自引：0，他引：2  

A. K. Chakraborty  A. K. Raina  M. Ramulu  P. B. Choudhury  A. Haldar  P. Sahoo  C. Bandopadhyay 《Geotechnical and Geological Engineering》2004,22(4):477-496

The empirical models available for prediction of the tunnel blast results like pull ratio, specific charge, specific drilling and overbreak have some inherent shortcoming in absence of any parametric study at the backdrop. Hence, the models use different constituting parameters and provide values which differ widely. After a thorough review of literature and field investigations in the drivages of mines and tunnels some parameters were identified. Those parameters were subjected to Multiple Linear Regression analyses to filter out the most influencing ones which represent the rockmass properties, the tunnel configurations and the blast designs. A parameter called Tunnel Blasting Index (TBI) was conceptualized and was expressed in terms of those most influencing parameters. All the blast results observed during the filed investigations could be well related to a single index TBI. Some adjustments on account of shape of the tunnel and joint orientations, which were not addressed in the available models, are suggested in the developed models.  相似文献   

Novel transformation-based response prediction of shear building using interval neural network     

S Chakraverty  Deepti Moyi Sahoo 《Journal of Earth System Science》2017,126(3):32

Present paper uses powerful technique of interval neural network (INN) to simulate and estimate structural response of multi-storey shear buildings subject to earthquake motion. The INN is first trained for a real earthquake data, viz., the ground acceleration as input and the numerically generated responses of different floors of multi-storey buildings as output. Till date, no model exists to handle positive and negative data in the INN. As such here, the bipolar data in [ ?1, 1] are converted first to unipolar form, i.e., to [0, 1] by means of a novel transformation for the first time to handle the above training patterns in normalized form. Once the training is done, again the unipolar data are converted back to its bipolar form by using the inverse transformation. The trained INN architecture is then used to simulate and test the structural response of different floors for various intensity earthquake data and it is found that the predicted responses given by INN model are good for practical purposes.  相似文献   

Geochemical appraisal of mine discharge and tailing at Malanjkhand copper mine,India     

Sk. Md. Equeenuddin  Abhijit Panda  Vishal Singh  Prafulla Kumar Sahoo  Subhashis Sahu  Sumit Kumar Basantray 《Journal of the Geological Society of India》2017,89(2):209-215

Geophysical investigation using Vertical Electrical Sounding (VES), Electrical Resistivity Tomography (ERT) and Seismic Refraction at a proposed conference center site along Ajibode-Labani road, Ibadan, southwestern Nigeria has been carried out. The investigation aims at characterizing and delineating the subsurface strata to understand the weathered profile at the site. Understanding the weathered profile is essential in determining the suitability of the site for engineering construction of the future conference center. A total of 25 VES and 10 ERT profiles were acquired in a systematic grid pattern using both Schlumberger andWenner configurations with Allied omega terrameter. TheVES data were processed and analyzed using WinResist and the ERT data were inverted using RES2DINV. The data were combined to form a 3-D data set of the site and RES3DINV was used to produce the depth slices. Seismic refraction data were also acquired with an ABEM seismograph and processed using SeisImager and Fajseis software. Seismic data were used in understanding the velocity distribution and thickness. The results of VES, ERT and seismic refraction show good correlation. Four sub-surface layers were delineated: top layer of reworked sand, clayey sand/ lateritic hard pan, clay/ sandy clay and fracture/ fresh basement. The 3-D model permits a pictorial view of the sub-surface in relation to materials that overlie the basement. The thickness of unconsolidated materials to bedrock varies from 2.7 m to 12.2 m which revealed inhomogeneity in weathering under the shallow sub-surface. It is found that the integrated geophysical tool is well suited to characterize and delineate sub-surface structure (weathered profile) for engineering site characterization.  相似文献   

Pattern recognition in lithology classification: modeling using neural networks,self-organizing maps and genetic algorithms     

Sasmita Sahoo  Madan K. Jha 《Hydrogeology Journal》2017,25(2):311-330

Effective characterization of lithology is vital for the conceptualization of complex aquifer systems, which is a prerequisite for the development of reliable groundwater-flow and contaminant-transport models. However, such information is often limited for most groundwater basins. This study explores the usefulness and potential of a hybrid soft-computing framework; a traditional artificial neural network with gradient descent-momentum training (ANN-GDM) and a traditional genetic algorithm (GA) based ANN (ANN-GA) approach were developed and compared with a novel hybrid self-organizing map (SOM) based ANN (SOM-ANN-GA) method for the prediction of lithology at a basin scale. This framework is demonstrated through a case study involving a complex multi-layered aquifer system in India, where well-log sites were clustered on the basis of sand-layer frequencies; within each cluster, subsurface layers were reclassified into four depth classes based on the maximum drilling depth. ANN models for each depth class were developed using each of the three approaches. Of the three, the hybrid SOM-ANN-GA models were able to recognize incomplete geologic pattern more reasonably, followed by ANN-GA and ANN-GDM models. It is concluded that the hybrid soft-computing framework can serve as a promising tool for characterizing lithology in groundwater basins with missing lithologic patterns.  相似文献   

Morphological and microstructural characteristics of bauxite developed over a part of Precambrian Iron Ore Group of rocks,Sundergarh District,Eastern India     

Sudakshina Sahoo  Patitapaban Mishra  Birendra K. Mohapatra 《Arabian Journal of Geosciences》2017,10(1):12

Bauxite occurring as a blanket over volcanics of Precambrian Iron Ore Group in Kusumdih and Jaldih of Sundergarh district, Odisha, Eastern India exhibits four types of morphology viz. pisolitic, disseminated, spotted and massive. The volcanics/tuffs are altered to shale and is predominantly constituted of kaolinite. Microstructures documented in different morphologies of bauxite are collomorphous, framework, chain, stalactitic, reticulate, vesicle filled and foliated-platy types. Gibbsite, diaspore and kaolinite exhibit the abovementioned morphological and microstructural features. The morphological and microstructural characteristics are interpreted in terms of genetic evolution of aluminous minerals of bauxite in such a setup. Gibbsite and diaspore are formed through solution and precipitation/recrystallisation from kaolinite booklets present in parent tuffaceous shales. Some diaspores were formed at the expense of gibbsites. Small well-ordered kaolinites are of authigenic nature. Kaolinite formed inside a localized closed system containing supersaturated solution exhibits growth spirals. The textural and morphological diversities of the bauxite, abundance of well-ordered bauxite minerals and the absence of any iron/silica phase along with limited occurrence of primary kaolinite together suggest that the deposit has attained a high degree of bauxitisation in weathering environment at surface temperature.  相似文献   

Seismic strengthening of RC columns using external steel cage     

Pasala Nagaprasad  Dipti Ranjan Sahoo  Durgesh C. Rai 《地震工程与结构动力学》2009,38(14):1563-1586

Steel caging technique is commonly used for the seismic strengthening of reinforced concrete (RC) columns of rectangular cross‐section. The steel cage consists of angle sections placed at corners and held together by battens at intervals along the height. In the present study, a rational design method is developed to proportion the steel cage considering its confinement effect on the column concrete. An experimental study was carried out to verify the effectiveness of the proposed design method and detailing of steel cage battens within potential plastic hinge regions. One ordinary RC column and two strengthened columns were investigated experimentally under constant axial compressive load and gradually increasing reversed cyclic lateral displacements. Both strengthened columns showed excellent behavior in terms of flexural strength, lateral stiffness, energy dissipation and ductility due to the external confinement of the column concrete. The proposed model for confinement effect due to steel cage reasonably predicted moment capacities of the strengthened sections, which matched with the observed experimental values. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献