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171.
172.
A simple and efficient methodology for Markovnikov addition of azoles with vinyl acetate catalyzed by potassium tert-butoxide is described.N-heterocyclic compounds are synthesized from simple and commercially available starting materials under mild conditions in high yields. 相似文献
173.
This note reports the dependence of shape factor corresponding to the portion of wall behind a berm and above the ground on the angle of berm; the results have been obtained by thermal simulation of heat transfer between the ground and the wall through the berming. 相似文献
174.
Shalini Bagchi Kasturi Roychowdhury A.P. Mishra A. Roy Chowdhury 《Communications in Nonlinear Science & Numerical Simulation》2010,15(2):275-280
Excitation of nonlinear waves in a quantum dusty plasma with various effects is analyzed when the geometry is cylindrical.This introduces the effect of finite boundary conditions on the solitary waves so generated. it is observed that the nonlinear equation deduced is cylindrical KP–Burger type leading to the generation of Shock Wave. Different situations which arises in various parameter regions are considered separately and the form of the nonlinear excitations are obtained explicitly. 相似文献
175.
Anamika Mishra Karel Matou? Kumud B. Mishra Ladislav Nedbal 《Journal of fluorescence》2009,19(5):905-913
Automatic discrimination of plant species is required for precision farming and for advanced environmental protection. For
this task, reflected sunlight has already been tested whereas fluorescence emission has been only scarcely considered. Here,
we investigated the discriminative potential of chlorophyll fluorescence imaging in a case study using three closely related
plant species of the family Lamiaceae. We compared discriminative potential of eight classifiers and four feature selection methods to identify the fluorescence
parameters that can yield the highest contrast between the species. Three plant species: Ocimum basilicum, Origanum majorana and Origanum vulgare were grown separately as well as in pots where all three species were mixed. First, eight statistical classifiers were applied
and tested in simulated species discrimination. The performance of the Quadratic Discriminant Classifier was found to be the
most efficient. This classifier was further applied in combination with four different methods of feature selection. The Sequential
Forward Floating Selection was found as the most efficient method for selecting the best performing subset of fluorescence
images. The ability of the combinatorial statistical techniques for discriminating the species was also compared to the resolving
power of conventional fluorescence parameters and found to be more efficient. 相似文献
176.
R. Neugart E. W. Otten K. Wendt S. Ahmad N. Panigrahy R. W. Dougherty K. C. Mishra T. P. Das J. Andriessen 《Hyperfine Interactions》1990,59(1-4):145-148
Using the relativistic linked cluster many-body perturbation procedure we have obtained the hyperfine field at the nucleus
of the Ra+ ion in the2S1/2 ground state. There is good agreement between the calculated magnetic moment of213Ra and the results of a recent Zeeman measurement by the collinear laser beam technique. Detailed comparison is carried out
between our result and earlier ones. 相似文献
177.
Chandreshwar Thakur Ram Babu Mishra 《International Journal of Theoretical Physics》1990,29(9):1029-1037
Steady flow of an inviscid, incompressible two-phase magnetofluid with infinite electrical conductivity is treated. With one ignorable coordinate in a general orthogonal curvilinear system, general solutions of the equations, considering number densityN constant throughout the motion, are obtained. 相似文献
178.
We consider a setting where there is a manufacturer who wants to procure multiple items from a set of suppliers each of whom can supply one or more of these items (bundles). We design an ascending price auction for such a setting which implements the Vickrey–Clarke–Groves outcome and truthful bidding is an ex post Nash equilibrium. Our auction maintains non-linear and non-anonymous prices throughout the auction. This auction has a simple price adjustment step and is easy to implement in practice. As offshoots of this auction, we also suggest other simple auctions (in which truthful bidding is not an equilibrium by suppliers) which may be suitable where incentives to suppliers are not a big concern. Computer simulations of our auction show that it is scalable for the multi-unit case, and has better information revelation properties than its descending auction counterpart. 相似文献
179.
An attempt has been taken to study the feasibility of scale-invariant theory in Bianchi type VI
h
space-time with a time dependent gauge function (Dirac gauge) and a matter field in the form of a perfect fluid with isotropic matter pressure. It is found that Bianchi type VI
h
(h = 1) space-time is feasible in this theory whereas Bianchi type VI
h
(h = -1) and VI
h
(h = 0) space-times are not feasible. In the feasible case a non-singular model for the universe filled with disorder radiation is constructed and some of its physical behaviors are studied. 相似文献
180.
We discuss the production of particles via interaction with the earth’s gravitational field. Explicit calculations are done
for high energy scalars passing through earth’s gravitational field. We show for example, that the width for the scalar processφ→3φ can become comparable with a typical weak decay width at an energy scale of a few TeV. (Similar conclusions can be drawn about
particles that ultimately couple to some scalar field.) We speculate that similar processes may be responsible for many of
the anomalies in the 10–104 TeV experimental data. 相似文献