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71.
Thomas?Oommen Debasmita?MisraEmail author Anupma?Prakash Sukumar?Bandopadhyay Sathy?Naidu John?J.?Kelley 《Natural Resources Research》2011,20(1):11-24
Multiple Regressive Pattern Recognition Technique (MRPRT) is an adapted approach for improved geologic resource estimation.
We developed and tested this approach for the Platinum (Pt) bearing region near Goodnews Bay, Alaska, which presents an example
of a complex depositional environment. We applied geospatial and pattern recognition methods to assess the spatial distribution
of offshore Pt in the Goodnews Bay area from point data collected by various agencies. We used the coefficient of correlation
(r) and the Nash–Sutcliffe efficiency (E) to quantitatively assess the degree of accuracy of the estimated Pt distribution. We split the study area, based on trend
analysis, into two regions: inside the Bay and outside the Bay. We could not obtain appreciable estimates from the geospatial
and pattern recognition methods. Using MRPRT, we were able to improve r from 0.57 to 0.93 and the E from 28.31 to 92.91 inside the Bay. We achieved improvement in r from 0.55 to 0.61 and E from 28.46 to 34.52 outside the Bay. The reasons for a non-significant improvement outside the Bay have been discussed. The
results indicate that the proposed MRPRT has wide application potential in georesource estimation where input data is often
scarce. 相似文献
72.
N. Prakash A. Garg 《International Journal of Environmental Science and Technology》2016,13(11):2675-2688
In the present study, the effectiveness of physicochemical treatment processes (coagulation and Fenton’s oxidation) was investigated for simulated dairy wastewater (pH = 7.3, chemical oxygen demand (COD) = 3600 mg/l, 5-day biochemical oxygen demand (BOD5) = 1950 mg/l, total Kjeldahl nitrogen (TKN) = 87 mg/l, and total phosphorous (TP) = 14 mg/l). Plain and ballasted coagulation runs were carried out in a jar apparatus, while Fenton’s oxidation was performed in a three-neck glass reactor. Ballasted coagulation caused an enhancement in the settling rate of sludge though no significant enhancement in the removal of organics was observed. Individually, coagulation and Fenton’s oxidation processes resulted in ~67 and 80 % COD removals, respectively, from the wastewater. The sequential treatment exploring coagulation followed by Fenton’s oxidation showed overall COD, BOD5, TKN, and TP reductions of ~93, 97, 84, and 70 %, respectively, from the wastewater. However, a biological post-treatment would be required to achieve the effluent discharge standards. The removal of proteins, fats, and amino acids from wastewater was confirmed from Fourier transform infrared analysis of the settled sludge (obtained after coagulation process). Preliminary cost analysis suggested coagulation and the sequential treatment (i.e. coagulation followed by Fenton’s oxidation) as the preferred options. 相似文献
73.
This paper presents the effects of soil layering on the characteristics of basin-edge induced surface waves and associated
strain and aggravation factor. The simulated results revealed surface wave generation near the basin-edge. The first mode
of induced Love wave was obtained in models having increasing velocity with depth and a large impedance contrast between the
soil layers. Amplitude amplification or de-amplification of body waves was proportional to the impedance contrast between
the soil layers. The average aggravation factor was inversely proportional to the impedance contrast between the soil layers
in case of increasingvelocity models and proportional in case of decreasing-velocity basinedge models. On the other hand,
the maximum strain was inversely proportional to the impedance contrast between the soil layers in both cases. On the average,
strain was greater in case of increasing-velocity models but the average aggravation factor was greater in case of decreasingvelocity
models. 相似文献
74.
In the present paper integrated appraisals of landform evolution and their geomorphic features, drainage networks across the upper part of Yamuna river basin have been attempted by using various geomorphic indices such as watershed, drainage density (D), drainage texture, stream-gradient index (SL), hypsometric integral (HI), drainage basin asymmetry (AF), mountain front sinuosity (Smf), sinuosity index (SI), valley floor height and width ratio (Vf) and data of historical earthquakes in characterizing the basin in view of relative index of active tectonics (RIAT) on DEM in geographic information systems (GIS) environment to assess the influence of recent tectonics on geomorphologic growth of the basin.The substantiated RIAT classes through some field observations and corroborated by recent seismicity reveal the recent activation of Yamuna tear faults in the basin with delineation of four RIAT classes such as class-1 (inactive 9.8% of the area), class-2 (low active; 16.40% of the area), class-3 (moderately active; 42.38% of the area) and class-4 (very active; 31.62%). The results suggest that the Himalayan frontal thrust (HFT) and Yamuna tear (YT) located in the basin is morphogenic in nature and got activated several times as evidenced by number of seismic activities in the basin and adjoining regions. The incision, and sharp turning of rivers, crenulations and warping of cross beddings/laminations and silt/clay beds and lenses, megascopic and mesoscopic faulting in sediment sequences suggest a very active nature of the HFT and YT till date in association with three prolific microseismogenic weak zones These active discontinuities appear to support the formation and development of different deformational features in sediment sequences which may be indirectly related to subduction and underthrusting of Indian plate under Eurasian plate below the Himalayan mountain chain. 相似文献
75.
Prakash Abhishek Piazolo Sandra Saha Lopamudra Bhattacharya Abhijit Pal Durgesh Kumar Sarkar Saheli 《International Journal of Earth Sciences》2018,107(6):2265-2292
International Journal of Earth Sciences - In the present study we investigate the microstructural development in mullite, quartz and garnet in an anatectic migmatite hosted within a Grenvillian-age... 相似文献
76.
J. Singh A. Ali V. Prakash 《International Journal of Environmental Science and Technology》2014,11(6):1759-1770
The present article explores the ability of five different combinations of two adsorbents (Arachis hypogea shell powder and Eucalyptus cameldulensis saw dust) to remove Pb(II) from synthetic and lead acid batteries wastewater through batch and column mode. The effects of solution pH, adsorbent dose, initial Pb(II) concentration and contact time were investigated with synthetic solutions in batch mode. The Fourier transform infrared spectroscopy study revealed that carboxyl and hydroxyl functional groups were mostly responsible for the removal of Pb(II) ions from test solutions. The kinetic data were found to follow pseudo-second-order model with correlation coefficient of 0.99. Among Freundlich and Langmuir adsorption models, the Langmuir model provided the best fit to the equilibrium data with maximum adsorption capacity of 270.2 mg g?1. Column studies were carried out using lead battery wastewater at different flow rates and bed depths. Two kinetic models, viz. Thomas and Bed depth service time model, were applied to predict the breakthrough curves and breakthrough service time. The Pb(II) uptake capacity (q e = 540.41 mg g?1) was obtained using bed depth of 35 cm and a flow rate of 1.0 mL min?1 at 6.0 pH. The results from this study showed that adsorption capacity of agricultural residues in different combinations is much better than reported by other authors, authenticating that the prepared biosorbents have potential in remediation of Pb-contaminated waters. 相似文献
77.
This study investigates the decrease in the frequency of onset vortex of summer monsoon during recent decades using the National Center for Environmental Prediction–National Center for Atmospheric Research reanalysis (1982–2011) data. Onset vortices are known to occur over the Arabian Sea mini warm pool where the sea surface temperature peaks just before the onset of monsoon. Even though the Arabian Sea mini warm pool intensifies during the recent decades, they are not seen as a regular feature. It is found from the analysis of irrotational and non-divergent wind component at 850 and 200 hPa that during the recent decades, convergent winds dominate at upper levels and divergent winds at lower levels which inhibits convection. Moreover, the cyclonic shear vorticity shows a decrease in the recent decades which tend to reduce the boundary layer moisture convergence and lower tropospheric humidity which is an important component for the initiation of a cyclonic system. The recent decades are characterized by weak convection due to the presence of strong northerlies and descending motion at lower levels in the southeast Arabian Sea. The response of atmospheric circulation to the interdecadal variations in the warm pool and the corresponding decrease in the frequency of onset vortex formation is analyzed in detail. 相似文献
78.
Vibrational transition probabilities namely Franck-Condon factors and r-centroids have been evaluated using an approximate analytical method for theC-X system of V0. Morse potential energy curves forX
4 – andC
4 – states of V0 have been constructed using the latest spectroscopic data. The value of r-centroids for the band have been found to increase linearly with the corresponding wavelength. We show results for new transition and ten new bands in the umbral spectrum of the Sun. 相似文献
79.
Sushma Panigrahy Shibendu Shankar Ray K. R. Manjunath P. S. Pandey S. K. Sharma Anil Sood Manoj Yadav P. C. Gupta N. Kundu Jai Singh Parihar 《Journal of the Indian Society of Remote Sensing》2011,39(3):355-364
Cropping system study is not only useful to understand the overall sustainability of agricultural system, but also it helps
in generating many important parameters which are useful in climate change impact assessment. Considering its importance,
Space Applications Centre, took up a project for mapping and characterizing major cropping systems of Indo-Gangetic Plains
of India. The study area included the five states of Indo-Gangetic Plains (IGP) of India, i.e. Punjab, Haryana, Uttar Pradesh,
Bihar and West Bengal. There were two aspects of the study. The first aspect included state and district level cropping system
mapping using multi-date remote sensing (IRS-AWiFS and Radarsat ScanSAR) data. The second part was to characterize the cropping
system using moderate spatial resolution multi-date remote sensing data (SPOT VGT NDVI) and ground survey. The remote sensing
data was used to compute three cropping system performance indices (Multiple Cropping Index, Area Diversity Index and Cultivated
Land Utilization Index). Ground survey was conducted using questionnaires filled up by 1,000 farmers selected from 103 villages
based on the cropping systems map. Apart from ground survey, soil and water sampling and quality analysis were carried out
to understand the effect of different cropping systems and their management practices. The results showed that, rice-wheat
was the major cropping system of the IGP, followed by Rice-Fallow-Fallow and Maize-Wheat. Other major cropping systems of
IGP included Sugarcane based, Pearl millet-Wheat, Rice-Fallow-Rice, Cotton-Wheat. The ground survey could identify 77 cropping
systems, out of which 38 are rice-based systems. Out of these 77 cropping systems, there were 5 single crop systems, occupying
6.5% coverage (of all cropping system area), 56 double crop systems with 72.7% coverage, and 16 triple crop systems with 20.8%
coverage. The cropping system performance analysis showed that the crop diversity was found to be highest in Haryana, while
the cropping intensity was highest in Punjab state. 相似文献
80.