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331.
G. P. OBI Reddy K.Chandra Mouli S. K. Srivastav C. V. Srinivas A. K. Maji 《Journal of the Indian Society of Remote Sensing》2000,28(1):19-32
In the present study efforts have been made to evaluate ground water potential zones for ground water targeting using IRS-IC LISS-II1 geo-coded data on 1:50,000 scale. The drainage, geology, geomorpholgoy and lineament information has been generated and integrated to evaluate hydro-geomorphological characteristics of the Gairnukh watershed, Bhandara district, Maharashtra for delineation of ground water potential zones. The analysis reveals that the deep valley fills with thick alluvium have excellent, shallow valley tills and deeply weathered pediplains with thin alluvium have very good and moderately weathered pediplains in the geological formations of Tirodi Gneiss and Sausar Groups have god ground water potential and these units are highly favourable for ground water exploration and development. Shallow weathered pediments in geological formations of Tirodi Gnesis and Sausar Groups are marked under moderate ground water potential zone. Shallow weathered pediplains in geological formations of Tiridi Gneiss and Sausor Groups are grouped under limited ground water potential category, except along the fractures/lineaments. Structural hills in geological formations of Tirodi Gneiss and Sausar Groups have poor ground water prospects. Inselbergs and Linear ridges in geological formations of Tirodi Gneiss are grouped under very poor ground water prospects zone. The good inter-relationship was found among the geological units, geomorphological units, lineament density, hydro-geomorphological zones and ground water yield data. 相似文献
332.
The analysis of two-parameter families of triple close approaches occurring in stellar systems is studied in a series of three
papers. This paper deals with the role of triple encounters with low initial velocities and equal masses in the evolution
of stellar systems. It shows how a condition of complete collapse may be perturbed to obtain well-established two-parameter
families of asymmetric triple close approaches with the formation of a binary and with systematic regularity of escape of
the third body. Our results also indicate that the conjecture of Szebehely viz., `The measure of escaping orbits is significantly
higher than the measure of stable orbits' is likely to be true. Further our results differ from that of Agekian's escape probability
criterian. The second paper deals with the role of triple encounters with low initial velocities and equal masses in the evolution
of stellar systems in 3D space. The third and last paper offers applications in stellar systems.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
333.
This is the third and last of a series of papers dedicated to the effect of triple encounters with the formation of a binary
and escape of the third body on the evolution of stellar systems. Previously obtained results are applied to several astronomical
models of triplets formed by sun-like stars, white dwarfs and neutron stars.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
334.
Astrophysics - Aminomethanol (NH2CH2OH) and N-Methylhydroxylamine (CH3NHOH) are isomers of each other, and have astrochemical importance. To our knowledge, they have not been analyzed so far in any... 相似文献
335.
The National Research Council has estimated that over 126,000 contaminated groundwater sites are unlikely to achieve low ug/L clean‐up goals in the foreseeable future. At these sites, cost‐effective, long‐term monitoring schemes are needed in order to understand the long‐term changes in contaminant concentrations. Current monitoring optimization schemes rely on site‐specific evaluations to optimize groundwater monitoring frequency. However, when using linear regression to estimate the long‐term zero‐order or first‐order contaminant attenuation rate, the effect of monitoring frequency and monitoring duration on the accuracy and confidence for the estimated attenuation rate is not site‐specific. For a fixed number of monitoring events, doubling the time between monitoring events (e.g., changing from quarterly monitoring to semi‐annual monitoring) will double the accuracy of estimated attenuation rate. For a fixed monitoring frequency (e.g., semi‐annual monitoring), increasing the number of monitoring events by 60% will double the accuracy of the estimated attenuation rate. Combining these two factors, doubling the time between monitoring events (e.g., quarterly monitoring to semi‐annual monitoring) while decreasing the total number of monitoring events by 38% will result in no change in the accuracy of the estimated attenuation rate. However, the time required to collect this dataset will increase by 25%. Understanding that the trade‐off between monitoring frequency and monitoring duration is not site‐specific should simplify the process of optimizing groundwater monitoring frequency at contaminated groundwater sites. 相似文献
336.
Tourism industry has become an important part of Indian economy, and tourism development has been, however, concentrated to a few areas. Accumulation of tourism activities has reached the critical stage in most of the tourism centers, which pose serious threats to the natural environment. The Bhyundar Valley of Nanda Devi Biosphere Reserve (NDBR) in Uttarakhand State of the Indian Himalaya is a burning example of such problems. Land use/cover changes, deforestation and accumulation of garbage are some of the negative impacts of unregulated tourism in the valley. Unsustainable activities of tourists and villagers in the valley make such problems very severe. To deal with the ongoing problems and ensure community involvement in tourism management and environmental conservation, the Biosphere Reserve Authority introduced ecotourism in the form of Eco Development Committees (EDCs) in the Bhyundar Valley. Study reveals that many problems associated with tourism have been minimized to some extent with the help of EDCs but few are still prevailing in valley. However, the existing attempts to conserve the valley from the negative effects of tourism are inadequate and modifications are needed in the current initiatives. 相似文献
337.
Estimating boundary currents from satellite altimetry: A case study for the east coast of India 总被引:1,自引:0,他引:1
Fabien Durand Doraiswamy Shankar Florence Birol S. Satheesh Chandra Shenoi 《Journal of Oceanography》2008,64(6):831-845
We present a methodology to derive surface geostrophic current from a newly released altimetric sea-level data set. TOPEX/Poseidon
data were first completely reprocessed from Geophysical Data Records using new algorithms accommodating marginal seas and
coastal conditions. The methodology applied to the reprocessed data essentially consists of a smoothing of the raw along-track
coastal altimetric data at scales at which the geostrophic equilibrium holds. This was reduced to a computational procedure
using a set of objective criteria. We have applied the method to the East India Coastal Current (EICC) at the western boundary
of the Bay of Bengal. This paper first examines the quality of the new data set, which compares well with tide-gauge data;
the current we derived is consistent with independent estimates. Our methodology reveals the full spectrum of the along-shore
current, ranging from intra-seasonal to inter-annual time scales, from the deep ocean to the shelf-break area where the EICC
exists. The algorithm can be applied to any coastal region where an order of the Rossby radius can be defined, and it therefore
opens up bright prospects for mapping the variability of other boundary-current systems in the world ocean from altimetry. 相似文献
338.
The present study was carried out in Tungnath alpine meadows of Kedarnath Wild Life Sanctuary, Western Himalaya from subalpine to upper alpine zone. A total of four summits were selected along an altitudinal gradient and sampled for detailed vegetation analysis using multi summit approach as per Global observation research initiative in alpine environments(GLORIA). Species richness, diversity, and evenness among four summits as well as the interaction between environmental variables with plant communities were assessed. Monthly mean soil temperature was calculated using data retrieved from geo-precision temperature logger in order to identify the trend of soil temperature among different season and altitudinal gradient and its implications to plant communities. Soil samples were analyzed fromeach summit by collecting randomized composite soil samples. The indirect non-metric multidimensional scaling(NMDS) and direct canonical correspondence analysis(CCA) tools of ordination techniques to determine the linkage between plant species from various sample summits and biotic/abiotic environmental gradients were used in the present study. The results of the study demonstrated increase in species richness as soil temperature increases, the ecotone representing summits were found most warm summits followed by highest species richness. Annual soil temperature increased by 1.43°C at timberline ecotone. Whereas, at upper alpine zone the soil temperature increased by 0.810 C from year 2015 to 2016. S?rensen's similarity index was found to be increased between subalpine and upper alpine zone with increase in the presence of subalpine plant species at upper alpine zone. Both the ordination tools separate the subalpine summit and their respective vegetation from summits representingtimberline ecotone and upper alpine zone. Soil p H, altitude, soil cation exchange capacity were found as the key abiotic drivers for distribution of plant species. 相似文献
339.
K. P. Singh G. C. Stewart N. J. Westergaard S. Bhattacharayya S. Chandra V. R. Chitnis G. C. Dewangan A. T. Kothare I. M. Mirza K. Mukerjee V. Navalkar H. Shah A. F. Abbey A. P. Beardmore S. Kotak N. Kamble S. Vishwakarama D. P. Pathare V. M. Risbud J. P. Koyande T. Stevenson C. Bicknell T. Crawford G. Hansford G. Peters J. Sykes P. Agarwal M. Sebastian A. Rajarajan G. Nagesh S. Narendra M. Ramesh R. Rai K. H. Navalgund K. S. Sarma R. Pandiyan K. Subbarao T. Gupta N. Thakkar A. K. Singh A. Bajpai 《Journal of Astrophysics and Astronomy》2017,38(2):29
The Soft X-ray focusing Telescope (SXT), India’s first X-ray telescope based on the principle of grazing incidence, was launched aboard the AstroSat and made operational on October 26, 2015. X-rays in the energy band of 0.3–8.0 keV are focussed on to a cooled charge coupled device thus providing medium resolution X-ray spectroscopy of cosmic X-ray sources of various types. It is the most sensitive X-ray instrument aboard the AstroSat. In its first year of operation, SXT has been used to observe objects ranging from active stars, compact binaries, supernova remnants, active galactic nuclei and clusters of galaxies in order to study its performance and quantify its characteriztics. Here, we present an overview of its design, mechanical hardware, electronics, data modes, observational constraints, pipeline processing and its in-orbit performance based on preliminary results from its characterization during the performance verification phase. 相似文献
340.
We have calculated Einstein A-coefficients for electric dipole transitions in the ground vibrational state of the moleculesH
2
D
+ andD
2
H
+, between the rotational levels up to 2200 and 2000 cm–1, respectively. These A-coefficients are used for computing the mean radiative life-times of the levels. These data play an important role in analysing the spectra from astronomical objects. 相似文献