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1.
P K Litoria Ajay Mathur P K Sharma Charan kamal Singh 《Journal of the Indian Society of Remote Sensing》1997,25(4):261-272
Level-II urban land use information available in this Town and Country Planning maps, Survey of India toposteets for Phillaur and Phagwara towns and the land use information generated through visual interpretation of satellite data was digitized, integrated and analysed using PAMAP GIS. The land use map of the two towns suggest that the wastelands located near the point of present disposal can be utilised for siting sewage treatment plants in both the towns. The STP sites suggested were away from the thickly habttared area. It was observed that some of the areas earmarked for locating STP’s, were partially brought under habitation before the execution of the preject. Hence, it is necessary that planning and execution of such projects should be done on a real time basis so that the sites identified for locating STP’s are not brought under other land uses. 相似文献
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Long-range precipitation forecasts are useful when managing water supplies.Oceanicatmospheric oscillations have been shown to influence precipitation.Due to a longer cycle of some of the oscillations,a short instrumental record is a limitation in using them for long-range precipitation forecasts.The influence of oscillations over precipitation is observable within paleoclimate reconstructions;however,there have been no attempts to utilize these reconstructions in precipitation forecasting.A data-driven model,KStar,is used for obtaining long-range precipitation forecasts by extending the period of record through the use of reconstructions of oscillations.KStar is a nearest neighbor algorithm with an entropy-based distance function.Oceanic-atmospheric oscillation reconstructions include the El Nino-Southern Oscillation(ENSO),the Pacific Decadal Oscillation(PDO),the North Atlantic Oscillation(NAO),and the Atlantic Multi-decadal Oscillation(AMO).Precipitation is forecasted for 20 climate divisions in the western United States.A 10-year moving average is applied to aid in the identification of oscillation phases.A lead time approach is used to simulate a one-year forecast,with a 10-fold cross-validation technique to test the models.Reconstructions are used from 1658-1899,while the observed record is used from 1900-2007.The model is evaluated using mean absolute error(MAE),root mean squared error(RMSE),RMSE-observations standard deviation ratio(RSR),Pearson’s correlation coefficient(R),NashSutcliffe coefficient of efficiency(NSE),and linear error in probability space(LEPS) skill score(SK).The role of individual and coupled oscillations is evaluated by dropping oscillations in the model.The results indicate ’good’ precipitation estimates using the KStar model.This modeling technique is expected to be useful for long-term water resources planning and management. 相似文献
4.
Mantle heat flow and thermal structure of the northern block of Southern Granulite Terrain, India 总被引：1，自引：0，他引：1
Continental shield regions are normally characterized by low-to-moderate mantle heat flow. Archaean Dharwar craton of the Indian continental shield also follows the similar global pattern. However, some recent studies have inferred significantly higher mantle heat flow for the Proterozoic northern block of Southern Granulite Terrain (SGT) in the immediate vicinity of the Dharwar craton by assuming that the radiogenic elements depleted exposed granulites constitute the 45-km-thick crust. In this study, we use four-layered model of the crustal structure revealed by integrated geophysical studies along a geo-transect in this region to estimate the mantle heat flow. The results indicate that: (i) the mantle heat flow of the northern block of SGT is 17 ± 2 mW/m2, supporting the global pattern, and (ii) the lateral variability of 10–12 mW/m2 in the surface heat flow within the block is of crustal origin. In terms of temperature, the Moho beneath the eastern Salem–Namakkal region appears to be at 80–100 °C higher temperature than that beneath the western Avinashi region. 相似文献
5.
N. K. Patel R. K. Saxena Ajay Shiwalkar 《Journal of the Indian Society of Remote Sensing》2007,35(1):73-79
A field experiment was conducted to study the effect of vegetation cover on soil spectra and relationship of spectral indices with vegetation cover. Multi-date spectral measurements were carried out on twelve wheat fields. Five sets of measurements were taken during the growth period of wheat crop. Field reflectance data were collected in the range 350 to 1800 nm using ASD spectroradiometer. Analysis of data was done to select narrow spectral bands for estimation of ground cover. The ratio of reflectance from vegetation covered soil and reflectance from bare soil indicated that spectral reflectance at 670 and 710 nm are the most sensitive bands. Two bands in visible (670 and 560 nm), three bands in near infrared (710, 870 and 1100 nm) and three bands in middle infrared (1480, 1700 and 1800 nm) were found highly correlated with fractional cover. Vegetation indices developed using narrow band spectral data have been found to be better than those developed using broad- band data for estimation of ground cover. 相似文献
6.
Ajay Paul 《Journal of the Geological Society of India》2010,76(4):414-418
The Garhwal-Kumaun region continues to accumulate the built-up of strain energy like the other regions of the Himalaya. But
this sector unlike the other sectors is yet to release this accumulated strain energy which can be in the form of great earthquake.
The region has sufficient strain energy to generate earthquake of M>8. The analysis of seven hundred ten local events recorded
by ten station broad band network between August’07 to February’10 shows that most of the seismic events recorded in this
region continue to occur from shallow depths (< 25 km). The evaluation of source parameters from p-wave spectral analysis
indicates that the events have low stress drop values. The region continues to release energy in the form of smaller magnitude
earthquakes. The epicentral location map indicates that Munsiari Thrust, which is located south of the Main Central Thrust
is more active. 相似文献
7.
K. K. Ajay A. K. Chaubey K. S. Krishna D. Gopala Rao D. Sar 《Journal of Earth System Science》2010,119(6):803-813
Multi-channel seismic reflection profiles across the southwest continental margin of India (SWCMI) show presence of westerly
dipping seismic reflectors beneath sedimentary strata along the western flank of the Laccadive Ridge — northernmost part of
the Chagos-Laccadive Ridge system. Velocity structure, seismic character, 2D gravity model and geographic locations of the
dipping reflectors suggest that these reflectors are volcanic in origin, which are interpreted as Seaward Dipping Reflectors
(SDRs). 相似文献
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This paper presents the computation of time series of the 22 July 2007 M 4.9 Kharsali earthquake. It occurred close to the Main Central Thrust (MCT) where seismic gap exists. The main shock and
17 aftershocks were located by closely spaced eleven seismograph stations in a network that involved VSAT based real-time
seismic monitoring. The largest aftershock of M 3.5 and other aftershocks occurred within a small volume of 4 × 4 km horizontal extent and between depths of 10 and 14 km.
The values of seismic moment (M
∘) determined using P-wave spectra and Brune’s model based on f
2 spectral shape ranges from 1018 to 1023 dyne-cm. The initial aftershocks occurred at greater depth compared to the later aftershocks. The time series of ground motion
have been computed for recording sites using geometric ray theory and Green’s function approach. The method for computing
time series consists in integrating the far-field contributions of Green’s function for a number of distributed point source.
The generated waveforms have been compared with the observed ones. It has been inferred that the Kharsali earthquake occurred
due to a northerly dipping low angle thrust fault at a depth of 14 km taking strike N279°E, dip 14° and rake 117°. There are
two regions on the fault surface which have larger slip amplitudes (asperities) and the rupture which has been considered
as circular in nature initiated from the asperity at a greater depth shifting gradually upwards. The two asperities cover
only 10% of the total area of the causative fault plane. However, detailed seismic imaging of these two asperities can be
corroborated with structural heterogeneities associated with causative fault to understand how seismogenesis is influenced
by strong or weak structural barriers in the region. 相似文献
9.
Dynamic Subsidence Characteristics in Jharia Coalfield,India 总被引：1，自引：0，他引：1
Amar Prakash Ajay Kumar Kalendra Bahadur Singh 《Geotechnical and Geological Engineering》2014,32(3):627-635
Surface ground movements are usually described by a number of characteristic indices such as vertical displacement, horizontal strain and slope, which are an inevitable consequence of underground mining. Every point at the surface over a panel is subjected to strain and slope during mining and its investigation is essential to assess the safety of surface structures. Therefore, the behaviour of dynamic active and residual subsidence was studied for a few panels of Jharia coalfield. The subsidence and slope were linearly related to time. Compressive and tensile strains showed typical fluctuating characteristic behaviour. The rate of mining being a key and controlling parameter for rate of subsidence their inter-relationship was developed, which showed a rational trend. Compressive and tensile strains and slope showed poor correlation with rate of face advance. 相似文献
10.
In a warming climate, atmospheric wave activity and associated weather patterns may change, although conflicting results have been reported on this topic. Additionally, atmospheric wave changes in a future climate have mainly focused on waves of a specified spatial scale, rather than a particular spatiotemporal scale. Here, changes in the variability of Rossby waves of multiple spatiotemporal scales are analyzed using the wavenumber-frequency power spectrum, a tool commonly applied to analyze atmospheric equatorial waves. Daily 500 hPa geopotential height data over 40°–60°N from historical (1950–2005) and future (2006–2099) simulations from 20 models in the Coupled Model Intercomparison Project Phase 5 (CMIP5) under the RCP8.5 scenario were analyzed. When compared to the historical period, the late 21st century climate projections showed a decline in spectral power for both eastward and westward propagating waves with wavenumbers greater than 8 that spanned over all frequencies in all seasons, but an increase in mean power for eastward propagating waves with wavenumbers 1–7 over all frequencies was shown in winter and spring. This increase in power was accompanied by increased variance, i.e., an increased meridional extent of 500 hPa ridges and troughs, and was the result of increases in the mean number of high amplitude events and duration of activity within this wave band. These results indicate that large-scale (~ 104 km) eastward propagating weather systems may intensify with higher amplitudes for ridges and troughs, while short-scale (102–103 km) weather systems may decrease in their intensity due to reduced variability in the late 21st century under the high emissions scenario. Potential mechanisms for these changes are discussed, including enhanced Arctic warming and midlatitude-tropical interactions. 相似文献