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51.
Jasleen Kaur Dhillon A. K. Mishra 《Journal of the Indian Society of Remote Sensing》2014,42(2):469-474
The present study is focussing on that how Landsat 7 ETM+ can be effectively used for estimation of Trophic State Index for Sukhna Lake. Sukhna Lake in Chandigarh has undergone lot of changes in last few decades. The depth and area both reduced tremendously. The shrinkage of the lake is due to the siltation and inadequate water volumes flowing to it. The Trophic State Index has been estimated by using secchi disk transparency and Landsat 7 ETM+ data. The in situ observations for parameters like pH, DO were measured by using multiparameter water quality instrument TROLL 9500. The best tested interpolation technique has been used to generate in situ images. The results have shown that the lake is in Hypereutrophic condition since 2000. 相似文献
52.
This paper presents the method proposed to calculate the bearing capacity of a square footing under oblique and eccentric oblique loading condition (satisfying both shear failure and settlement criteria) resting on fiber reinforced sand layer underlain by sand with geosynthetic/fabric sheet at the interface. Large direct shear tests were carried out to investigate the shear strength parameters of sand and randomly distributed fiber reinforced sand (RDFS) and soil-plastic fabric sheet bond. The ultimate bearing capacity of RDFS was determined using direct shear results. Non-dimensional charts proposed by Kumar (Behaviour of eccentrically–obliquely loaded footing on reinforced earth slab. Ph.D. thesis, University of Roorkee, Roorkee, India, 2002) were used to consider the contribution of plastic fabric sheet in increasing the bearing capacity. Also, for calculating the settlement, horizontal deformation and tilt at a given pressure the regression analysis of plate load test data have been carried out. The predicted values of ultimate bearing capacity, settlement, horizontal deformation and tilt are compared with the experimental values which are in good agreement with each other. There appeared to be an increase in the residual shear strength and angle of internal friction of RDFS. 相似文献
53.
54.
In this problem, one of the primaries of mass \(m^{*}_{1}\) is a rigid spherical shell filled with a homogeneous incompressible fluid of density ρ 1. The smaller primary of mass m 2 is an oblate body outside the shell. The third and the fourth bodies (of mass m 3 and m 4 respectively) are small solid spheres of density ρ 3 and ρ 4 respectively inside the shell, with the assumption that the mass and the radius of the third and the fourth body are infinitesimal. We assume that m 2 is describing a circle around \(m^{*}_{1}\) . The masses m 3 and m 4 mutually attract each other, do not influence the motions of \(m^{*}_{1}\) and m 2 but are influenced by them. We also assume that masses m 3 and m 4 are moving in the plane of motion of mass m 2. In the paper, equilibrium solutions of m 3 and m 4 and their linear stability are analyzed. There are two collinear equilibrium solutions for the system. The non collinear equilibrium solutions exist only when ρ 3=ρ 4. There exist an infinite number of non collinear equilibrium solutions of the system, provided they lie inside the spherical shell. In a system where the primaries are considered as earth-moon and m 3,m 4 as submarines, the collinear equilibrium solutions thus obtained are unstable for the mass parameters μ,μ 3,μ 4 and oblateness factor A. In this particular case there are no non-collinear equilibrium solutions of the system. 相似文献
55.
Ramanpreet Kaur Biswajit Paul Brijesh Kumar Ram Sagar 《Monthly notices of the Royal Astronomical Society》2008,386(4):2253-2261
We have investigated multiband optical photometric variability and stability of the Hα line profile of the transient X-ray binary IGR J01583+6713. We set an upper limit of 0.05 mag on photometric variations in the V band over a time-scale of three months. The Hα line is found to consist of non-Gaussian profile and quite stable for a duration of two months. We have identified the spectral type of the companion star to be B2 IVe while the distance to the source is estimated to be ∼4.0 kpc. Along with the optical observations, we have also carried out analysis of X-ray data from three short observations of the source, two with the Swift –XRT and one with the RXTE –PCA. We have detected a variation in the absorption column density, from a value of 22.0 × 1022 cm−2 immediately after the outburst down to 2.6 × 1022 cm−2 four months afterwards. In the quiescent state, the X-ray absorption is consistent with the optical reddening measurement of E ( B − V ) = 1.46 mag. From one of the Swift observations, during which the X-ray intensity was higher, we have a possible pulse detection with a period of 469.2 s. For a Be X-ray binary, this indicates an orbital period in the range of 216–561 d for this binary system. 相似文献
56.
Harjeet Kaur Srimanta Gupta Surya Parkash Raju Thapa Rumpa Mandal 《Environmental Earth Sciences》2017,76(9):339
Flood hazards are the most destructive among all natural disasters and are a constant threat to human’s life and property. Effective disaster risk reduction strategies can be improved by geospatial approach in the way of producing information and knowledge that are useful to plan truly effective actions for the protection from floods. This research aims to develop a quantified predictive model of flood susceptibility in the Ghatal and Tamluk subdivision of Medinipur district of West Bengal, India, by means of empirically selected and weighted spatial predictors of flood. The weighted prediction model is used to quantify the spatial associations between individual geospatial factors within the flood inundated study area. Yule’s coefficient and distance distribution analysis are used to assign weights to individual geo-factors, and finally weighted spatial predictors are integrated to a multi-class index overlay analysis to derive the spatially explicit predictive model of flood susceptibility. The resultant susceptibility model reveals that approximately 32.35 and 52.99% of the total study areas (3261.45 km2) are under the category of high-to-moderate flood susceptible zone. Quantitative results of this study could be integrated into the policy process in the formulation of local and national government plans for the future flood mitigation management and also to develop appropriate infrastructure in order to protect the lives and properties of the common people of the Medinipur district. 相似文献
57.
Karanjot Kaur Brar Vishwa Bandhu Singh Chandel 《Journal of the Indian Society of Remote Sensing》2012,40(1):97-107
Wetlands play a vital role in maintaining groundwater levels in an area. This is true for Punjab that was bestowed with several
natural wetlands in the flood plains of its rivers. These natural wetlands have never been mapped and their existence has
not been acknowledged. The large scale agricultural development in the state has made it India's leading food producing state.
This development was done at the cost of certain ecologically sensitive parts, mainly the flood plains thus leading to the
demise of wetlands. This paper is an attempt to retrace the lost wetlands that were existed in the flood plains of the three
major rivers: Satluj, Beas and Ravi in the present day Punjab at the beginning of 20th century. A majority of these wetlands
have not been documented so far and do not even have names. The purpose is to emphasize their elimination in addition to establishing
a baseline dataset that can be a tool for wetland planning and management. 相似文献
58.
T.K. Rout D.K. Sengupta G. Kaur Surender Kumar 《International Journal of Mineral Processing》2006,80(2-4):215-222
Decontamination of radioactive effluents of low or intermediate level of radioactivity generated from different nuclear industries is done through the chemical precipitation route. The precipitates thus formed are of very fine sizes thereby requiring flocculation for faster settlement. The presence of polyacrylamide-based polymer not only enhances settling velocity but also increases removal of dissolved non-radioactive as well as radioactive metal ions from the liquid. About 99.5% of Cu2+ and Fe3+ ions are removed due to the presence of cationic Rishabh 611. Flocculation by either cationic or anionic flocculant has shown improvement in removal of radioactive strontium while turbidity of the liquid is reduced to a very low value (0.8 NTU). Decontamination factors (DF) of the effluents from different plants are improved by 3–5 times. 相似文献
59.
The in-plane motion of a Geosynchronous satellite under the gravitational effects of the sun, the moon and the oblate earth
has been studied. The radial deviation (Δr) and the tangential deviation (r
cΔθ) have been determined. Herer
c represents the synchronous altitude. It has been seen that the sum of the oscillatory terms in Δr for different inclinations is a small finite quantity whereas the sum of the oscillatory terms inr
cΔθ for different inclinations is quite large due to the presence of the low-frequency terms in the denominator 相似文献
60.
ABSTRACTGlobalisation, supply–demand dynamics, uneven development, enhanced connectivity including the better flow of information, communication and the reduced cost of travel have encouraged the global integration of nursing labour markets. Developed regions of the world have attracted internationally educated nurses (IENs) because of growing healthcare needs. India, along with the Philippines, has become a key supplier of nurses in the global economy. Traditionally the supply of nurses was heavily regionalised in south India, especially Kerala, but of late Punjab, in north India, has played an increasing role in nurse training and migration as the profession has become more respected and more international. This paper uses survey and interview data to detail the recent interest in nursing as a channel for independent female international migration from Punjab, and to examine how migratory ambitions have developed over the last decade in parallel with the changing status of nursing as an internationally respected profession. We identify growing interest in international migration for nursing students and their increased intention to pursue employment opportunities in Australia and New Zealand. This research highlights how nursing and care migration are increasingly structured by international circuits of training and employment, and how such circuits alter migrant and occupational geographies on the ground in sending regions. 相似文献