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31.
Pamela Woo Arun K. Misra Mehdi Keshmiri 《Celestial Mechanics and Dynamical Astronomy》2013,117(3):263-277
Relative motion of binary asteroids, modeled as the full two-body planar problem, is studied, taking into account the shape and mass distribution of the bodies. Using the Lagrangian approach, the equations governing the motion are derived. The resulting system of four equations is nonlinear and coupled. These equations are solved numerically. In the particular case where the bodies have inertial symmetry, these equations can be reduced to a single equation, with small nonlinearity. The method of multiple scales is used to obtain a first-order solution for the reduced nonlinear equation. The solution is shown to be sufficient when compared with the numerical solution. Numerical results are provided for different example cases, including truncated-cone-shaped and peanut-shaped bodies. 相似文献
32.
A. Banerjee M. Jha A. K. Mittal N. J. Thomas K. N. Misra 《Marine and Petroleum Geology》2000,17(10):7
Source rock screening reveals five laterally extending potential sources (PS) in the Paleogene. The PSs are SR5 and SR6 in dominantly marine early Eocene to late Paleocene Cambay Shale formation, and SR7, SR8/9, and SR11/12 in dominantly freshwater early Paleocene Olpad formation. Only 3 PSs, SR11/12, SR8/9, and SR7 have attained vitrinite reflectance of 0.75% at 45, 7, and 2 mybp, respectively. Chromatographic and isotope data of oils and PS samples suggest that mainly the Olpad source rocks: SR7 and SR8/9 contributed to the discovered oils. The Cambay Shale source rocks, SR5 and SR6, contrary to the prevalent view, possibly have no significant contribution towards the accumulated oils. 相似文献
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34.
Haiqin Li Masao Kanamitsu Song-You Hong Kei Yoshimura Daniel R. Cayan Vasubandhu Misra Liqiang Sun 《Climatic change》2014,122(4):609-619
This study examines a future climate change scenario over California in a 10-km coupled regional downscaling system of the Regional Spectral Model for the atmosphere and the Regional Ocean Modeling System for the ocean forced by the global Community Climate System Model version 3.0 (CCSM3). In summer, the coupled and uncoupled downscaled experiments capture the warming trend of surface air temperature, consistent with the driving CCSM3 forcing. However, the surface warming change along the California coast is weaker in the coupled downscaled experiment than it is in the uncoupled downscaling. Atmospheric cooling due to upwelling along the coast commonly appears in both the present and future climates, but the effect of upwelling is not fully compensated for by the projected large-scale warming in the coupled downscaling experiment. The projected change of extreme warm events is quite different between the coupled and uncoupled downscaling experiments, with the former projecting a more moderate change. The projected future change in precipitation is not significantly different between coupled and uncoupled downscaling. Both the coupled and uncoupled downscaling integrations predict increased onshore sea breeze change in summer daytime and reduced offshore land breeze change in summer nighttime along the coast from the Bay area to Point Conception. Compared to the simulation of present climate, the coupled and uncoupled downscaling experiments predict 17.5 % and 27.5 % fewer Catalina eddy hours in future climate respectively. 相似文献
35.
A new method of analysis of piles in multi‐layered elastic soil subjected to a torque at the head is developed. The differential equation governing the angle of twist in the pile is derived using the variational principles of mechanics. The method of initial parameters is used to obtain closed‐form solutions of the angle of twist and torque in the pile as a function of depth. The inputs required for the analysis are shear moduli of pile and soil, pile geometry and thickness of soil layers. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
36.
The gravitational instability of an infinite homogeneous self-gravitating and infinitely conducting gas-particle medium is considered in the presence of suspended particles and a variable horizontal magnetic field varying in vertical direction. It is found that the Jeans's criterion of instability remains unaffected even if the effects due to suspended particles and variable horizontal magnetic field are included. 相似文献
37.
Thermosolutal-convective instability of a stellar atmosphere is considered. The criteria for monotonic instability are derived. The effects of a variable horizontal magnetic field and the simultaneous presence of a uniform rotation and a uniform horizontal magnetic field have been considered on the thermosolutal-convective instability. The criteria derived for monotonic instability are found to hold good in the presence of a variable horizontal magnetic field as well as in the presence of a uniform rotation and a uniform horizontal magnetic field. 相似文献
38.
Unit regional value (URV) and unit regional weight (URW) are relatively new concepts which are used to measure the intensity of the development of the mineral resources of any particular region. URV and URW of the mineral resources of India have been evaluated by sector, by commodity, as well as by state. The results are compared with values for the U.S.A. established by earlier workers and which can be taken as a standard for comparison with the mineral resources of other regions. URV of India, evaluated through the years 1898–1985, shows that the total mineral resources produced stands at $24.4 billion U.S. (deflated to 1967 value). Log URV of India lies below one standard deviation of the value for the states of the U.S. Like the U.S. India's major contribution to its URV is from fuels, but it is much less compared to that of the U.S. Next to fuels, metals, nonmetals, construction materials, and precious materials follow in that order. Except for two states, viz. Bihar and West Bengal, all other states are just below two standard deviations of the states of the U.S. The state of J&K is even much lower than the two standard deviations mark. It is concluded that India has a high potential for undiscovered mineral resources. However, this will require a large investment in exploration, on the order of Rs. 7760 crores, in the next few years. 相似文献
39.
Variously shaped discrete bodies with reflectance higher than the associated vitrinite occur in Permian coals in India, Australia and Africa and the Carboniferous coals of the United States, Canada and Europe. These bodies have been variously named by different authors. In the present paper they are described as ‘resino-inertinites’ as suggested by Lyons et al. (1982).Based on available information and our observations on Carboniferous and Permian coals, it is presumed that resino-inertinites were formed mainly from the resinous (resinite) and to some extent from the phlobaphinitic or corpocollinitic substances. Various morphological patterns developed on resino-inertinites have been interpreted to be governed by the chemical composition of their precursors and the degree of oxidation or fusinization during coalification. Influences of other vvariables viz., paleoenvironmental, paleodepositional, tectonic set up etc. on resino-inertinites are not clearly recognizable probably because all the previous effects were masked by subsequent fusinization.Different morphological features of resino-inertinites associated with early diagenetic and secondary mineralization have caused much confusion in their proper identification and classification. In order to resolve this problem, an attempt has been made to ascertain the source of resins in Indian Permian coals and their subsequent mode of transformation into resino-inertinites during coalification.Further, by critically evaluating morphological features of resino-inertinites and keeping the chemical nature of their precursors in view, a classification scheme has been proposed categorizing them into 3 types. The classification proposed may prove as a useful means for coal-seam correlation. 相似文献
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