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101.
S. S. Ray Anil Sood Gargi Das Sushma Panigrahy P. K. Sharma J. S. Parihar 《Journal of the Indian Society of Remote Sensing》2005,33(2):181-188
In this study, an attempt has been made to suggest crop diversification based on soil and weather requirements of different
crops. State level spatial databases of various agro-physical parameters such as rainfall, soil texture, physiography and
problem soil along with the agricultural area derived from remote sensing data were integrated using GIS. A raster based modelling
approach was followed to arrive at suitable zones for practicing different cropping systems. The results showed that the south-western
Punjab is suitable for low water requiring crops such as desi cotton, pearl millet, gram etc., where as north-eastern Punjab
with high rainfall and excess drainage should practice maize based cropping system. Rice can be substituted by maize and other
crops in Central Punjab, where water table is going down fast. Using this approach the area of rice based cropping system
can be reduced from present 24.7 lakh ha to 19.6 lakh ha, thereby reducing the degradation of valuable land and water resources. 相似文献
102.
103.
Seismic reliability analysis of structures 总被引:1,自引:0,他引:1
104.
Anil V. Kulkarni Sunil Dhar B. P. Rathore Babu Govindha Raj K. Rajeev Kalia 《Journal of the Indian Society of Remote Sensing》2006,34(1):39-46
Himalayas possess one of the largest resources of snow, ice and glaciers that act as a huge freshwater reservoir. Monitoring
the glaciers is important to assess the overall reservoir health of the Himalayas. Samudra Tapu is one of the largest glaciers
in Chandra basin of district Lahaul and Spiti, Himachal Pradesh. Based on the field investigations and the remote sensing
techniques. features such as accumulation area, ablation area snowline/equilibrium line, moraine-dammed lakes and permanent
snowfields were mapped. The glacial terminus was identified using moraine-dammed lake, as lake is located at down streamside
of the terminus. The total recession of glacier during the period of 38 years (1962–2000) is about 742 m with an average rate
of 19.5 m/yr. In addition, glacial extent is reduced from 73 to 65 km2 between 1962 and 2000. suggesting overall deglaciation of 11%. During field investigation. three stages of glaciation using
terminal moraine were identified. These moraines were mapped by merging LISS-II1 and PAN data. At the peak of glaciation.
the glacial terminus was extended 3.18 km downstream of terminus position in year 2000. Total area during peak of glaciation
period has been observed to be 77.67 km2, which is 12.67 km2 higher than the present glacier extent. 相似文献
105.
Singular spectrum isolates significant principal components in a time series from the embedded noise. This tool-kit is used
to reconstruct trend-free individual time series, formed by restricting the mean monthly hourly values of geomagnetic field
to one hour at a time at a low latitude station Alibag (dipole latitude 9.5°N). Each reconstructed component is extrapolated
over the next 12 values using an autoregressive model based on Burg’s maximum entropy algorithm. Details of a numerical approach
to increase the reliability of extrapolation are highlighted. The extrapolated reconstructed components are then combined
to generate predicted monthly values for each hour. The mean diurnal variation for any month obtained from the extrapolated
individual hourly time series compares favorably with the observations. This approach to Sq(H) modelling incorporating both
long and short term variations will be beneficial in the derivation of Dst index. 相似文献
106.
Anil Kumar Y J Bhaskar Rao V M Padma Kumari A M Dayal K Gopalan 《Journal of Earth System Science》1988,97(1):107-114
Palaeomagnetic, geochemical and geochronological studies have been conducted on a set of dolerite dykes intruding the Peninsular
gneisses near Huliyurdurga town, Karnataka, as a reconnaissance survey indicated a Cretaceous age for them. The dykes are
mainly tholeiitic in composition with their 87Sr/86Sr ratios tightly clustered around 0·7045. Their palaeomagnetic data (D
m
=329°,I
m
=−55°) and the corresponding palaeopole coordinates (λ
p
= 34°S,L
p
=108°E) are strikingly close to those of the Deccan Traps to the north. Whole rock K-Ar ages of these dykes ranging between
69 and 84 Ma are also similar to the range of K-Ar ages of the Deccan basalts. The chemical, palaeomagnetic and temporal coherence
between the dykes and the Deccan basalts indicate that they may indeed be tectonically related events. 相似文献
107.
An effective procedure is summarized without derivation for estimating the maximum response of a class of torsionally-coupled, multi-storey buildings due to earthquake ground motion characterized by response spectra. The analysis procedure is shown to be efficient and to provide insight into torsional coupling effects because the maximum response of such a torsionally-coupled, N-storey building in its njth mode of vibration is determined exactly by analysing (i) the response in the jth vibration mode (j = 1,2, N) of the corresponding torsionally-uncoupled, N-storey system; and (ii) the response in the nth vibration mode (n = 1, 2 for a one-way symmetric plan) of an associated torsionally-coupled, one-storey system. It is also demonstrated that an earlier, simpler approach in which the total (considering all vibration modes) response of the building is determined from the total response of the two simpler systems is strictly valid only under restrictive conditions, which are identified, but the simpler approach leads to results that are accurate to a useful degree. 相似文献
108.
Man has had to live with floods since the very inception of his existence. Fury of flood causes heavy damages to both life and property. Accurate flood inundation data is one of the essential requirements for effective management of flood problem. Remote Sensing methods are well suited for acquiring flood inundation data because of synoptic, repetitive coverage of the satellite data. This paper briefs on an attempt to map flood inundated areas in a part of Mahanadi river basin using remote sensing data. 相似文献
109.
The mechanical properties of particulate systems are studied from a micromechanics point of view. Two approaches, namely, computer simulation and micro-structural continuum modelling are used. The computer simulation method is used to study the uniformity of the strain field and effect of particle rotations. These results are then used to evaluate the applicability of the micro-structural continuum model. Potential applications of the micro-structural continuum model in the study of mechanical properties of soils are discussed. 相似文献
110.
A study on the bulk distributions and molecular structures of n-alkanes and polycyclic aromatic hydrocarbons (PAH) in organic matter of the sediments from the Bay of Bengal and the Eastern and Central Indian Basins was undertaken. The former two regions represent areas characterised by “normal” sedimentation while the third one mainly represents a region of “active tectonism”. Content of the hydrocarbons in the sediments of “normal” sedimentation ranges between 4.6 and 10.5 μg/g and aromatic hydrocarbons ranges between 0 and 0.38 μg/g. n-Alkanes in the sediments of the northern deep part of the Bay of Bengal consist mostly of long-chain structures (total C25–C33 up to 70%) with a high carbon preference index (CPI=3.01–3.43), indicating a large contribution of organic matter from terrigenous sources. The sediments from the Eastern Indian Basin have n-alkane distributions in which the long-chain components did not exceed 52.5% and the CPI was 1.7–1.90, indicating that the hydrocarbons are mostly derived from marine sources. Sharp increases of hydrocarbons are found in the vicinity of the tectonically active region of the Central Indian Basin, particularly in the sediments collected from the fracture zone. The total concentration of hydrocarbons increase to 170 μg/g and the aromatic hydrocarbons fraction to 156.3 μg/g. The proportion of short-chain n-alkanes increases up to 70%, CPI decreases to 0.76–1.12, and high concentrations of n-C16 (16–40%) occur, all of which are absent in the other samples. The molecular content of PAH includes the unsubstituted individual structures: biphenyl, fluorene, pyrene, perylene, benzo(ghi)perylene, and the groups of homologues of naphthalene, benzofluorene, phenanthrene and chrysene. The association of the PAH and composition of paraffin hydrocarbons in the surficial sediments of deformation zone indicate that these are the resultant products of hydrothermal processes. It is, therefore, suggested that the association and composition of the hydrocarbons in sediments can be utilised as a paleoceanographic parameter to decipher the history of tectonism of an area. 相似文献