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排序方式: 共有1236条查询结果,搜索用时 234 毫秒
1.
In this paper, we consider linear combinations of modified Baskakov operators. By use of several lemmas, we obtain the inverse
theorem (Theorem 1.1) and the saturation (Theorem 1.2) for those linear combinations. 相似文献
2.
The stereoselective intramolecular cyclizations of bis(cinnamyl)tosylamides and dimethyl bis(cinnamyl)malonates mediated by cerium(IV) ammonium nitrate leading to the synthesis of 3,4-trans-disubstituted pyrrolidines and cyclopentanes are described. 相似文献
3.
An efficient synthesis of isothiazolidines in good yields is described. 相似文献
4.
5.
Absolute total electron scattering cross sections for carbon dioxide have been measured at low electron energies using a photoelectron
source. The measurements have been carried out at 27 electron energies varying from 0.91–9.14 eV with an accuracy of ±3%.
The cross sections obtained in the present experiment have been compared with other measurements and theoretical computations. 相似文献
6.
Vijay Balasubramanian Donald Marolf Moshe Rozali 《General Relativity and Gravitation》2006,38(11):1529-1536
We argue that if black hole entropy arises from a finite number of underlying quantum states, then any particular such state
can be identified from infinity. The finite density of states implies a discrete energy spectrum, and, in general, such spectra
are non-degenerate except as determined by symmetries. Therefore, knowledge of the precise energy, and of other commuting
conserved charges, determines the quantum state. In a gravitating theory, all conserved charges including the energy are given
by boundary terms that can be measured at infinity. Thus, within any theory of quantum gravity, no information can be lost
in black holes with a finite number of states. However, identifying the state of a black hole from infinity requires measurements
with Planck scale precision. Hence observers with insufficient resolution will experience information loss.
First Award in the 2006 Essay Competition of the Gravity Research Foundation. 相似文献
7.
M.K. Gupta Vijay Gupta Manoj Kumar 《Journal of Mathematical Analysis and Applications》2007,330(2):799-816
In the present paper we introduce a new family of linear positive operators and study some direct and inverse results in simultaneous approximation. 相似文献
8.
In this paper, we suggest and analyze a new two-step predictor–corrector type iterative method free from second derivatives for solving nonlinear equations of the type f(x)=0. This new method includes the two-step Newton method as a special case. We prove that the new iterative method is of fourth-order. Several examples are given to illustrate the efficiency of this new method and its comparison with other iterative methods. This method can be considered as a significant improvement of the Newton method and its variant forms. 相似文献
9.
The present paper deals with the study of a Durrmeyer-type integral modification of certain modified Baskakov operators. Here
we study simultaneous approximation properties for these operators by using the iterative combinations. We obtain an asymptotic
formula and an error estimation in terms of higher order modulus of continuity for these operators.
相似文献
10.
In the present paper, we study the rate of convergence in simultaneous approximation for the Bézier variant of the Baskakov-Beta operators by using the decomposition technique of functions of bounded variation. 相似文献