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101.
Atul Jain 《Applied Physics A: Materials Science & Processing》1978,15(3):323-333
We derive the properties of the image obtained for an ocean wave whose cross-section may be given byσ
w(x,y,y) and surface profile byh(x,y,t).σ
w andh are functions representing the wave phenomena, but whose exact properties are determined by the ocean wave surface properties,
for an ocean wavelength ofλ
w, heightH, and orbital frequency ω. We calculate the effect of defocusing of the wave image due to its temporal motion, and derive
both the resolution of the radar system if no focus compensation is provided in the processor and the necessary distance the
azimuth telescope has to be moved to provide diffraction-limited imaging. We illustrate these results for data taken by the
JPL synthetic aperture radar over Hurricane Gloria on September 30, 1976, and the ERIM radar over Marineland, Florida, on
December 15, 1975.
This paper presents the results of one phase of research carried out at the Jet Propulsion Laboratory, California Institute
of Technology, under Contract NAS 7-100, sponsored by the special programs office and the Seesat program office under Mr.
F.C. Williams and Mr. S.W. McCandless of the National Aeronautics and Space Administration. 相似文献
102.
Atul D. Sontakke Kaushik Biswas Ashis K. Mandal Kalyandurg Annapurna 《Journal of fluorescence》2010,20(1):425-434
This paper reports on the preparation and systematic analysis of energy transfer mechanisms in Nd3+–Yb3+–Er3+ co-doped new series of barium-alumino-metaphosphate glasses. The time resolved fluorescence of Nd3+ in triply doped Ba–Al-metaphosphate glasses have revealed that, Yb3+ ions could function as quite efficient bridge for an energy transfer between Nd3+ and Er3+ ions. As a result, a fourfold emission enhancement at 1.54 μm of Er3+ ions has been achieved through an excitation of 4F5/2 level of Nd3+ at 806 nm for the glass having 3 mol% Yb3+ with an energy transfer efficiency reaching up to 94%. Decay of donor (Nd3+) ion fluorescence has been analyzed based on theoretical models such as direct energy transfer model (Inokuti–Hirayama) and
migration assisted energy transfer models (Burshtein’s hopping and Yokota–Tanimoto’s diffusion). The corresponding energy
transfer parameters have been evaluated and discussed. Primarily, electrostatic dipole–dipole (s ~ 6) interactions are found
to be responsible for the occurrence of energy transfer process in theses glasses. 相似文献
103.
Bianchi Type-V Magnetized String Cosmological Model with Variable Magnetic Permeability for Viscous Fluid distribution 下载免费PDF全文
We investigate the Bianchi type-V magnetized string cosmological model with variable magnetic permeability for viscous fluid distribution. The magnetic field is due to an electric current produced along the x-axis. Thus the magnetic field is in yz-plane and F23 is the only non-vanishing component of electromagnetic field tensor Fij. To obtain the deterministic model in terms of cosmic time t, we assume the condition ξθ const where ξ is the coefficient of bulk viscosity and θ the expansion in the model. 相似文献
104.
We used variationally improved perturbation theory (VIPT) in calculating the slope and curvature of Isgur-Wise (I-W) function
with the Cornell potential −$
\frac{{4\alpha _s }}
{{3r}}
$
\frac{{4\alpha _s }}
{{3r}}
+br + c instead of the usual stationary state perturbation theory as done earlier. We used −(4α
s
/3r), i.e. the Coulombic potential, as the parent and the linear one, i.e. br+c as the perturbed potential in the theory and calculated the slope and curvature of Isgur-Wise function including three states
in the summation involved in the first-order correction to wave function in the method. 相似文献
105.
The generalized Stokes parameters, which are two-point extensions of conventional Stokes parameters, are determined for a pair of points in the cross-section of a partially coherent broadband light beam. For this purpose, using a two-mirror and two-beam-splitter assembly, unpolarized, linearly polarized and partially polarized electromagnetic beams are generated. This simple experimental method for determining generalized Stokes parameters establishes an analogy with the experimental scheme of determining conventional Stokes parameters, which in succession contributes to appreciable reduction in uncertainty in the measurements. 相似文献
106.
Colloidal thin films of varying rigidity detaching from a substrate under an electric field induced stress are studied by video microscopy. For soft films, the process of detachment shows single-particle dynamics, analogous to desorption. For rigid films, a collective delamination spanning hundreds of particles occurs. A competition among the rigidity of the film, the interaction with the substrate, and the external stress leads to a correlation length over which the film delaminates at a critical stress. The phenomenon is described as a dynamical transition in a disordered elastic medium. 相似文献
107.
108.
Abstract The range and energy-loss of 16.34 MeV/u 238U in Kapton-polyamide plastic have been measured by the nuclear track technique. The experimental ranges are compared with two sets of theoretical values. It has been observed that ranges obtained from the computer code ‘DEDXT’ are found to be 5–8% lower as compared to measured ones whereas those from Northcliffe and Schilling are about 10–15% overestimated above 8 MeV/u. 相似文献
109.
110.
In this paper, an approach to achieve fault diagnosis and Fault Tolerant Control in a typical bottle-filling plant using event based techniques is discussed. For this purpose, the plant is modeled using Hybrid Petri nets which enable study and analysis with regard to the working of the plant. Once effective modeling is done based on two different case studies considered, new algorithms are proposed to achieve fault diagnosis and Fault Tolerant Control on the models developed. Finally, performance measures with regard to the models proposed are evaluated to check the correctness of the models developed. Both analytical and numerical results are obtained which are highly useful to understand plant behavior. 相似文献