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1.
Subramaniam S. Ravindra Babu Y. Rabindranath Bera Basheerullah Baig G. Viswanath P. V. Bajpai O. P. 《Journal of the Indian Society of Remote Sensing》2003,31(3):187-196
Journal of the Indian Society of Remote Sensing - A stationary, compact, spatially modulated Fourier Transform spectro-radiometer based on triangular, common path Sagnac interferometer has been... 相似文献
2.
For a pure phase at equilibrium with a polycomponent melt, two sets of expressions can be derived; one expressing its activity as a function of enthalpy, entropy, heat capacity and temperature, and the other by coupling a Flory-Huggins' polymerisation model with the van Laar heat of mixing term. Interaction parameters for binary and ternary systems have been computed at 1 bar by equating these two expressions. Assuming the interaction parameter to be independent of temperature, equilibrium temperatures at higher pressures can be calculated by an iterative procedure. Such retrieval calculations were carried out in simple eutectic, volatile-free systems like CaAl2Si2O8-CaMgSi2O6, Mg2SiO4-TiO2, MgSiO3-TiO2, Mg2SiO4-CaMgSi2O6, NaAlSi3O8-SiO2 and CaAl2Si2O8-CaMgSi2O6-Mg2SiO4. The close agreement between the theoretically retrieved and the experimentally determined equilibrium temperatures testifies to the validity of the model at higher pressures. The successful application of the model to simple eutectic, binary and ternary systems involving vastly dissimilar phases without imposing added constraints implies that it can be possibly extended to hitherto unknown systems provided the thermodynamic parameters of the phases involved are known. 相似文献
3.
D. Viswanath 《Celestial Mechanics and Dynamical Astronomy》2006,94(2):213-235
The restricted three-body problem describes the motion of a massless particle under the influence of two primaries of masses
1− μ and μ that circle each other with period equal to 2π. For small μ, a resonant periodic motion of the massless particle
in the rotating frame can be described by relatively prime integers p and q, if its period around the heavier primary is approximately 2π p/q, and by its approximate eccentricity e. We give a method for the formal development of the stable and unstable manifolds associated with these resonant motions.
We prove the validity of this formal development and the existence of homoclinic points in the resonant region. In the study
of the Kirkwood gaps in the asteroid belt, the separatrices of the averaged equations of the restricted three-body problem
are commonly used to derive analytical approximations to the boundaries of the resonances. We use the unaveraged equations
to find values of asteroid eccentricity below which these approximations will not hold for the Kirkwood gaps with q/p equal to 2/1, 7/3, 5/2, 3/1, and 4/1. Another application is to the existence of asymmetric librations in the exterior resonances.
We give values of asteroid eccentricity below which asymmetric librations will not exist for the 1/7, 1/6, 1/5, 1/4, 1/3,
and 1/2 resonances for any μ however small. But if the eccentricity exceeds these thresholds, asymmetric librations will exist
for μ small enough in the unaveraged restricted three-body problem. 相似文献
4.
Ther-centroids and Franck-Condon factors for the bands of theA
2 –X
2+ of CP,C
3 –X
3 of SiC, andB
2+ –X
2+ of CO+ molecules have been determined. The Franck-Condon factors are evaluated by the approximate analytical method of Jarmain and Fraser. The absence of the bands in these systems is explained. 相似文献
5.
The RKRV turning points for the ground states of NH and PH have been calculated, and the dissociation energies have been obtained by the curve-fitting procedure using empirical potential functions with the RKRV potential energy curves. The estimated values of dissociation energies are 3.45 ± 0.14 and 3.16 ± 0.12 eV for NH and PH, respectively. 相似文献
6.
Substructure hybrid simulation has been actively investigated and applied to evaluate the seismic performance of structural systems in recent years. The method allows simulation of structures by representing critical components with physically tested specimens and the rest of the structure with numerical models. However, the number of physical specimens is limited by available experimental equipment. Hence, the benefit of the hybrid simulation diminishes when only a few components in a large system can be realistically represented. The objective of the paper is to overcome the limitation through a novel model updating method. The model updating is carried out by applying calibrated weighting factors at each time step to the alternative numerical models, which encompasses the possible variation in the experimental specimen properties. The concept is proposed and implemented in the hybrid simulation framework, UI‐SimCor. Numerical verification is carried out using two‐DOF systems. The method is also applied to an experimental testing, which proves the concept of the proposed model updating method. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
7.
Application of hybrid‐simulation to fragility assessment of the telescoping self‐centering energy dissipative bracing system 下载免费PDF全文
Viswanath Kammula Jeffrey Erochko Oh‐Sung Kwon Constantin Christopoulos 《地震工程与结构动力学》2014,43(6):811-830
Substructure hybrid simulation has been the subject of numerous investigations in recent years. The simulation method allows for the assessment of the seismic performance of structures by representing critical components with physical specimens and the rest of the structure with numerical models. In this study the system level performance of a six‐storey structure with telescoping self‐centering energy dissipative (T‐SCED) braces is validated through pseudo‐dynamic (PsD) hybrid simulation. Fragility curves are derived for the T‐SCED system. This paper presents the configuration of the hybrid simulation, the newly developed control software for PsD hybrid simulation, which can integrate generic hydraulic actuators into PsD hybrid simulation, and the seismic performance of a structure equipped with T‐SCED braces. The experimental results show that the six‐storey structure with T‐SCED braces satisfies performance limits specified in ASCE 41. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
8.
A. G. Dessai D. B. Arolkar D. French A. Viegas T. A. Viswanath 《Journal of the Geological Society of India》2009,73(5):697-714
The Bondla mafic-ultramafic complex is a layered intrusion that consists predominantly of peridotites and gabbronorites. A
chromitite-pyroxenite-troctolite horizon serves as a marker to subdivide the intrusion into two zones. The Lower Zone displays
gravity stratified layers of chromite that alternate with those of olivine, which up-section are followed by olivine+pyroxene-chromite
cumulates. The Upper Zone comprises gabbroic rocks that exhibit uniform layering. On the basis of modal and cryptic variation
exhibited by the minerals this zone can be subdivided in to several lithohorizons starting from the troctolites at the base
to gabbronorites and leucogabbros at the top. The junction between the two zones is marked by the distinct reversal in cryptic
variation exhibited by the chromites and pyroxenes.
The peridotite chromites contain higher Al2O3 and lower Cr2O3 than those from the chromitite above. Similarly clinopyroxenes from pyroxenite and troctolites are more magnesian that those
from the peridotites stratigraphically below them. The complex in general is characterized by a gabbroic mineral assemblage
in which both Ca-rich and Capoor pyroxenes coexist and displays a Fe-enrichment trend providing evidence of evolution from
a contaminated tholeiitic magma. The rocks are characterized by low-TiO2; Ni, Cr and V, show negative correlation with Zr whereas the large ion lithophile elements (LILE) are positively correlated
and the Nb/La ratio varies from 0.4–0.6. These characteristics are consistent with a low-TiO2 sub-alkaline tholeiitic magma that may have been modified by fractional crystallization and successive injections of more
primitive melts in the magma chamber. The complex evolved in a periodically replenished magma chamber that consisted of two
separate but interconnected sub-chambers. 相似文献
9.
S. Kasi Viswanath N. K. Tripathi K. R. Salin 《Journal of the Indian Society of Remote Sensing》2018,46(4):675-685
Chlorophyll-a (Chl-a) and Suspended Solid Concentration (SSC) shows the productivity of water and their surrounding environment. These parameters can be effectively estimated through several remote sensing techniques. From the recent reports on the Gulf of Thailand, it is found that Chl-a and SSC are increasing in coastal areas due to changing environment caused by variations in the global carbon cycle, climate change and water pollution linking to anthropogenic conditions such as high population density and rapid urbanization in neighbouring coastal areas deteriorating the coastal and marine environment. Various models are evaluated in this study for estimation of marine Chl-a and SSC by employing Ocean Colour Monitor-2 sensor of Oceansat-2 satellite for Northern Gulf of Thailand. The retrieval of Chl-a and SSC by the atmospheric correction of visible bands from 400 to 700 nm to attain normalized water-leaving radiances and then a suitable algorithm is applied. The In-situ reflectance values of sea waters are measured using the ASD spectroradiometer. The reflectance values of the spectroradiometer are correlated for the same day atmospherically corrected satellite reflectance and the analysis offers high correlation R2 0.73. Satellite derived, Chl-a and SSC are correlated with observed in situ Chl-a and SSC. This analysis offered better correlation of R2 0.86 and 0.85 respectively with the algorithms of Chl-a and SSC. 相似文献
10.
Amish B. Shah N. M. Vadher Rajmal Jain Hemant Dave Vishal Shah K. S. B. Manian Satish Kayasth Vinod Patel Girish Ubale Kirit Shah Chirag Solanki M. R. Deshpande Ramkrishna Sharma C. N. Umapathy N. Viswanath Ravi Kulkarni P. S. Kumar 《Journal of Astrophysics and Astronomy》2006,27(2-3):299-304
The Solar X-ray Spectrometer (SOXS) mission onboard GSAT-2 Indian Spacecraft was launched on 08 May 2003 using GSLV-D2 rocket
by Indian Space Research Organization (ISRO). SOXS aims to study solar flares, which are the most violent and energetic phenomena
in the solar system, in the energy range of 4–56 keV with high spectral and temporal resolution. SOXS employs state-of-the-art
semiconductor devices, viz., Si-Pin and CZT detectors to achieve sub-keV energy resolution requirements. In this paper, we
present an overview of data acquisition, control, communication and computation of low energy payload of the SOXS mission. 相似文献