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51.
Balraj Sudhakar Leelasankar Kavisankar Ayyanar Ayyasamy Yesudhas Harold Robinson Kumar Raghvendra Long Hoang Viet Hoang Son Le 《Wireless Personal Communications》2021,118(2):1675-1696
Wireless Personal Communications - The Internet is being extensively used in various fields to serve billions of users, which leads to the number of network security issues. Here, Internet Protocol... 相似文献
52.
Graft copolymers of carboxymethyl cellulose and starch with polyacrylamide have been synthesized by grafting acrylamide onto carboxymethyl cellulose and starch, respectively, using a ceric-ion-initiated solution polymerization technique. These graft copolymers have been tested for their drag-reduction effectiveness, shear stability, and biodegradability. It has been shown that grafting enhances the drag-reduction effectiveness and shear stability and also that these factors are very much dependent on the length and number of grafts in the molecule. None of the graft copolymer solutions shows any microbial degradation up to 10 days. 相似文献
53.
Sudhakar Shanbhag M. P. Steinberg A. I. Nelson 《Journal of the American Oil Chemists' Society》1971,48(1):11-14
The radio frequency (r-f) saturation method was shown valid for determination of four edible oils in aqueous emulsions but
not in commercial margarine. The interference in case of margarine was shown to be due to nonfat solids. The signal from water
at low RF level was eliminated by converting to water of crystallization. Of three anhydrous salts studied for this purpose,
only magnesium perchlorate was satisfactory. The method could be made quantitative for oil in margarine only by addition of
carbon tetrachloride to the margarine before addition of magnesium perchlorate.
One of 10 papers to be published from the Symposium “Wide Line Nuclear Magnetic Resonance,” presented at the AOCS Meeting,
Minneapolis, October 1969. 相似文献
54.
Mishra Pavan Kumar Kumar Amitesh Pandey Sudhakar Singh Vinay Pratap 《Wireless Personal Communications》2018,103(3):2553-2573
Wireless Personal Communications - The 5G communication paradigm provides architecture of coexistence of device-to-device (D2D) communication with the current cellular communication. Direct D2D... 相似文献
55.
In general, solar radiations are the combination of beam plus diffuse and ground-reflected radiation. The availability of recorded data on a tilted surface is very rare due to lack of measuring equipment and techniques involved. In this study, a standard procedure is adopted for estimation of solar radiation on a tilted surface for a location in Central region of India. Solar radiation is estimated for three tilted positions: First, solar collector tilt equal to latitude angle, second, solar collector tilt equal to latitude angle +15° and third, solar collector tilt at latitude ?15°. Total global solar radiation estimated on the inclined surface for various photovoltaic (PV) modules was used to obtain the annual energy yield based on the estimated value. It was found that on an average, 14?kWh/m2 of annual energy output can be obtained for monocrystalline solar PV module corresponding to the inclination of 23.26° latitude at Bhopal. 相似文献
56.
Codeposited gadolinia silica composite films have been probed for their growth-dependent optical and microstructural properties using phase-modulated spectroscopic ellipsometry and scanning probe microscopy. The mean refractive indices were computed using an effective ellipsometric multilayer modeling approach. Most of the composite films have shown growth-induced nonlinear refractive indices to some extent. However, the mean optical properties have depicted interesting trends in the microstructural evolutions. Gadolinia silica composite films in the composition ratio ranging from 90:10 to 70:30 have depicted superior optical as well as morphological properties. Unlike conventional oxide films, these composite films displayed microstructural, spectral refractive index, and bandgap supremacy over the pure films. Such an observation cannot be explained by the empirical Moss law. Atomic force microscopy also revealed a superior morphology in the composite films. The autocorrelation and height-height correlation functional analysis have distinctly supported such superior microstructural features in the composite films, which justifies the supremacy of the optical properties. Such an observation has opened up possibilities to utilize such composite films toward deep-and extreme-ultraviolet spectral regions of the electromagnetic spectrum. 相似文献
57.
S. Sailaja S. J. Dhoble Nameeta Brahme B. Sudhakar Reddy 《Journal of Materials Science》2012,47(5):2359-2364
Novel green nanophosphors Ca2Gd2W3O14: Tb3+ were synthesized by solid state reaction method. From the X-ray diffraction profiles it is observed that Tb3+: Ca2Gd2W3O14 phosphors were crystallized in the form of tetragonal structure. The scanning electron microscopy (SEM) image shows that
the particle size is at around 300 nm. In addition to these the prepared powder phosphors were also examined by the energy
dispersive X-ray analysis (EDAX), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL) and mechanoluminescence
(ML) spectra. Emission spectra of Tb3+: Ca2Gd2W3O14 nanophosphors have shown bright green emission at 545 nm (5D4 → 7F5) with an excitation wavelength λexci = 374 nm (7F6 → 5G6). ML spectra shows the radiation effect on the Ca2Gd2W3O14: Tb3+ nanophosphors and from that it was observed that these phosphors are very less sensitive for lower exposure. 相似文献
58.
Prasad S 《Journal of the Optical Society of America. A, Optics, image science, and vision》2012,29(3):354-366
I present new lower and upper bounds on the minimum probability of error (MPE) in Bayesian multihypothesis testing that follow from an exact integral of a version of the statistical entropy of the posterior distribution, or equivocation. I also show that these bounds are exponentially tight and thus achievable in the asymptotic limit of many conditionally independent and identically distributed measurements. I then relate the minimum mean-squared error (MMSE) and the MPE by means of certain elementary error probability integrals. In the second half of the paper, I compare the MPE and MMSE for the problem of locating a single point source with subdiffractive uncertainty. The source-strength threshold needed to achieve a desired degree of source localization seems to be far more modest than the well established threshold for the different optical super-resolution problem of disambiguating two point sources with subdiffractive separation. 相似文献
59.
A linear stability analysis of two-layer fluid flows in an inclined channel geometry has been carried out. The onset of flow transitions and the spatio-temporal characteristics of secondary flows produced by the flow instabilities have been examined. The effects of density and viscosity stratifications and surface tension on flow structures also have been investigated at various values of Froude numbers (channel inclinations). Multi-domain Chebyshev–Tau spectral methods along with MATLAB QZ eigenvalue solver are used to determine the whole spectrum of the eigenvalues and associated eigenfunctions. The neutral stability diagrams and stability boundaries are constructed for various values of flow parameters. The onset of flow transitions and flow structures predicted by linear stability analysis are compared against experimental results and they agree reasonably well. The results presented in the present paper imply that the shear mode of flow transitions is the one likely to be identified in experiments. 相似文献
60.
Bhadraiah Vempati Mahesh V. Panchagnula Alparslan Öztekin Sudhakar Neti 《Acta Mechanica》2010,210(1-2):1-12
This paper presents experimental and numerical results of interfacial dynamics of liquid–liquid flows when an immiscible core liquid is introduced into a continuous liquid flow. The fully developed flow model predicts multiple solutions of the jet diameter over a range of dimensionless numbers: flow rate ratio, viscosity ratio, Bond and Capillary numbers. Experiments have been carried out using Polyethylene Glycol (PEG) and Canola oil to investigate the realizability of the three possible solutions predicted by the fully developed flow model. The measured values of inner fluid radii agree very well with the lower branch of the three branched solution while deviating from the top branch beyond a critical flow ratio value. This deviation is attributed to the fact that the flow develops a non-axisymmetric solution at this critical point. Computational fluid dynamics simulations have also been performed to examine the developing core annular flow and to compare the analytical solution results of liquid jet radius. The results predicted by numerical simulations agree very well with both the lower and upper branches of solution predicted by the analytical theory. 相似文献