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21.
SVM and SAM classifiers for the lithological mapping using Hyperion data in parts of Gadag schist belt of western Dharwar craton, Karnataka, India were used. The main objective of the present study is to assess and compare the potential use of Hyperion data set for lithological mapping. Accuracy assessment of the derived thematic maps was based on the analysis of the confusion matrix statistics computed for each classification map. For consistency, the same set of validation points were used in evaluating the accuracy of the lithological thematic maps produced. On the basis of the accuracy assessment results, it appears that SVM generally outperformed the SAM classifier in both OA accuracy and individual classes’ accuracies. OA accuracy and Kc for SVM is 96.93% and 0.9655, whereas for SAM it is 74.02% and 0.7085 respectively. SVM classification is the best in describing the spatial distribution and the cover density of each lithology, as was also indicated from the statistics of the individual class results. The individual class accuracy were also analyzed for the SVM and the result show that PA ranges from 87% to 100% and UA ranges from 91% to 100%, whereas for SAM ranges from 15% to 95%, and from 31% to 100% respectively. The SVM method could effectively classify and improve on the existing geological map for the Gadag schist belt (GSB) using hyperspectral data. The results could be validated through field visits. Therefore, it is concluded that hyperspectral remote sensing data can be efficiently used to improve existing maps, especially in areas where same rock types show variable degree of alteration over smaller spatial scales.  相似文献   
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In this article, we describe a simple yet effective method for insertion of observational datasets in a mesoscale atmospheric model used in one-dimensional configuration through Nudging. To demonstrate the effectiveness of this technique, vertical profiles of meteorological parameters obtained from GLASS Sonde launches from a tiny island of Kaashidhoo in the Republic of Maldives are injected in a mesoscale atmospheric model — Advanced Regional Prediction System (ARPS), and model simulated parameters are compared with the available observational datasets. Analysis of one-time nudging in the model simulations over Kaashidhoo show that incorporation of this technique reasonably improves the model simulations within a time domain of +6 to +12 Hrs, while its impact on +18 Hrs simulations and beyond becomes literally null.  相似文献   
24.

The potassium supplying capacity of the waste mica powder (WMP) was evaluated through chemical and biological means. Four different size fractions of the WMP were studied in laboratory by different chemical extractants. At the same time, experiment of the plant growth was conducted in pot using K-deficient soil. The K release from the WMP by different extractants followed an increasing trend with an increase in the fineness of the particles. The highest K release was recorded by boiling 1 M HNO3 (376.4–1726.4 mg kg?1) followed by 1 M ammonium acetate (33.5–226.5 mg kg?1), 0.01 M citric acid (31.6–158.3 mg kg?1) and water (12.0–112.0 mg kg?1) irrespective of the various size fractions. Significantly, higher cumulative K release from the WMP in successive extraction was recorded with 1 M boiling HNO3 that predicts its slow-release property. The K release by different extractants was correlated significantly and positively with the biomass yield and K uptake by plants. 1 M boiling HNO3 extractable K showed higher correlation values with the biomass yield and K uptake. Therefore, it suggests that the extractant might be a better indicator of K supplying capacity of the WMP. The plant intervention was able to extract 32.8% of total K from the WMP simultaneously improving the exchangeable and non-exchangeable K pool in soil. These above-mentioned results conclude that plants can get access to a significant amount of K from the WMP and it could be an effective source of K in highly weathered tropical soils under K deficiency.

  相似文献   
25.
GeoJournal - Urban expansion of the Indian metropolitan cities has reached the rural peripheries. There have been social, economic, and environmental consequences of this process of...  相似文献   
26.
Measurements of total ozone column and solar UV radiation under different atmospheric conditions are needed to define variations of both UV and ozone and to study the impact of ozone depletion at the Earth’s surface. In this study, spectral and broadband measurements of UV-B irradiance were obtained along with total ozone observations and aerosol optical depth measurements in the tropical urban region of Hyderabad, south India. We specifically used an Ultra-Violet Multifilter Rotating Shadow band Radiometer (UVMFR-SR), to measure UV irradiance in time and space. To assess the aerosol and O3 effects on ground-reaching UV irradiance, we used measurements from a Microtops II sun photometer in addition to the Tropospheric Ultraviolet Visible radiation (TUV) model. We also assessed the Defense Meteorological Satellite Program – Operational Line Scanner (DMSP-OLS) night time satellite data for inferring biomass burning fires during the study period. Results clearly suggested a negative correlation between the DMSP-OLS satellite derived fire count data and UVMFR-SR data suggesting that aerosols from biomass burning are directly attenuating UV irradiance in the study region. Also, correlation analysis between UV index and ozone measurements from sun photometer and TOMS-Ozone Mapping Instrument (OMI) indicated a clear decrease in ground reaching UV-B irradiance during higher ozone conditions. The higher levels are attributed to photochemical production of O3 during the oxidation of trace gases emitted from biomass burning. Results also suggested a relatively high attenuation in UV irradiance (~6% higher) from smoke particles than dust. We also found a relatively good agreement between the modeled (TUV) and measured UV irradiance spectra for different atmospheric conditions. Our results highlight the factors affecting UV irradiance in a tropical urban environment, south India.  相似文献   
27.
Carbon monoxide (CO), Ozone (O3) and Black Carbon (BC) aerosol mass concentrations in relation to planetary boundary layer (PBL) height measurements were analyzed from January–December, 2008 over tropical urban environment of Hyderabad, India. DMSP-OLS night-time satellite data were analyzed for fire occurrence over the region and its correlation with pollution concentrations over the urban region. Results of the study suggested considerable increase in CO and BC concentrations during early morning hours. Higher concentration of BC, CO and ozone was observed during pre-monsoon, post-monsoon and winter and lowest concentrations exhibited during monsoon season. NCEP/NCAR reanalysis winds suggested long range transport of aerosols and trace gases from forest fires are enhancing the pollutant concentrations over the study area.  相似文献   
28.
  • The present investigation was undertaken to evaluate the effects of three sublethal concentrations (1/10th, 1/15th and 1/20th fractions of 96 h LC50) of phenol (P), dinitrophenol (DNP), pentachlorophenol (PCP) and their antagonistic [(PCP + DNP)/P], additive [(DNP + P)/PCP] and synergistic [(P + DNP)/PCP] combinations, on several organic and inorganic components of haemopoetic systems of Notopterus notopterus after 30 d of exposure.
  • Glucose, lactate, total phosphorus, non-protein nitrogen, sodium, potassium, magnesium, calcium, iron and chloride were found to be increased in most cases while protein and cholesterol were found to be decreased.
  • It has been concluded that these alterations in blood parameters might be due to a damage or hyperactivity of liver, kidney and endocrine glands, the main centres for controlling the tissue metabolism.
  相似文献   
29.
Groundwater is important for managing the water supply in agricultural countries like Bangladesh. Therefore, the ability to predict the changes of groundwater level is necessary for jointly planning the uses of groundwater resources. In this study, a new nonlinear autoregressive with exogenous inputs(NARX) network has been applied to simulate monthly groundwater levels in a well of Sylhet Sadar at a local scale. The Levenberg-Marquardt(LM) and Bayesian Regularization(BR) algorithms were used to train the NARX network, and the results were compared to determine the best architecture for predicting monthly groundwater levels over time. The comparison between LM and BR showed that NARX-BR has advantages over predicting monthly levels based on the Mean Squared Error(MSE), coefficient of determination(R~2), and Nash-Sutcliffe coefficient of efficiency(NSE). The results show that BR is the most accurate method for predicting groundwater levels with an error of ± 0.35 m. This method is applied to the management of irrigation water source, which provides important information for the prediction of local groundwater fluctuation at local level during a short period.  相似文献   
30.
The Biot linearized quasi-static theory of fluid-infiltrated porous materials is used to formulate the problem of the two-dimensional plane strain deformation of a multi-layered poroelastic half-space by surface loads. The Fourier-Laplace transforms of the stresses, displacements, pore pressure and fluid flux in each homogeneous layer of the multi-layered half-space are expressed in terms of six arbitrary constants. Generalized Thomson-Haskell matrix method is used to obtain the deformation field. Simplified explicit expressions for the elements of the 6 × 6 propagator matrix for the poroelastic medium are obtained. As an example of the possible applications of the analytical formulation developed, formal solution is given for normal strip loading, normal line loading and shear line loading.  相似文献   
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