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91.
The total and differential cross sections for the electron and positron impact excitation of hydrogen from its initially excited metastable 22S state to 32S and 32P states are reported. A distorted-wave approximation theory is used for the calculation. The angular correlation parameters, Ly and alignment angle are also reported for 22S-32P excitation. For comparison, similar first Born results are also obtained. Interesting features are noted on comparing our distorted wave results with the first Born results as well as with the other available results forn
2S andn
2P (n=2,3) excitations from the ground 12S state of hydrogen. 相似文献
92.
When sound waves of high amplitude propagate, several non-linear effects occur. Ultrasonic studies in liquid mixtures provide
valuable information about structure and interaction in such systems. The present investigation comprises of theoretical evaluation
of the acoustic non-linearity parameter B/A of four binary liquid mixtures using Tong and Dong equation at high pressures and T=303.15 K. Thermodynamic method has also been used to calculate the non-linearity parameter after making certain approximations. 相似文献
93.
Amit Verma 《Physics letters. A》2009,373(16):1421-1428
Recently we have shown that the reduction of the Carruthers-Nieto symmetric quantum phase fluctuation parameter (U) with respect to its coherent state value corresponds to an antibunched state, but the converse is not true. Consequently reduction of U is a stronger criterion of nonclassicality than the lowest order antibunching. Here we have studied the possibilities of reduction of U in intermediate states by using the Barnett-Pegg formalism. We have shown that the reduction of phase fluctuation parameter U can be seen in different intermediate states, such as binomial state, generalized binomial state, hypergeometric state, negative binomial state, and photon added coherent state. It is also shown that the depth of nonclassicality can be controlled by various parameters related to intermediate states. Further, we have provided specific examples of antibunched states, for which U is greater than its Poissonian state value. 相似文献
94.
In this paper we study properties of numerical solutions of Burger’s equation. Burgers’ equation is reduced to the heat equation on which we apply the Douglas finite difference scheme. The method is shown to be unconditionally stable, fourth order accurate in space and second order accurate in time. Two test problems are used to validate the algorithm. Numerical solutions for various values of viscosity are calculated and it is concluded that the proposed method performs well. 相似文献
95.
Kaushal Verma 《Mathematische Annalen》2009,344(3):645-701
Let D be a bounded domain in C
2 with a non-compact group of holomorphic automorphisms. Model domains for D are obtained under the hypotheses that at least one orbit accumulates at a boundary point near which the boundary is smooth,
real analytic and of finite type.
The author was supported by DST (India) Grant No.: SR/S4/MS-283/05 and in part by a grant from UGC under DSA-SAP, Phase IV. 相似文献
96.
Ram U. Verma 《Rendiconti del Circolo Matematico di Palermo》1999,48(2):201-208
The solvability of a class of generalized strongly nonlinear variational inequality problems on nonempty closed convex sets
in Hilbert spaces is presented. 相似文献
97.
Jyoti Bhawan Singh Shakti Pratap Gupta Mohit Tripathi Sudhanshu Verma Alok Kumar Singh Devraj Yadav R. R. 《Acoustical Physics》2021,67(6):584-589
Acoustical Physics - We have estimated elastic, mechanical, thermal and ultrasonic properties, in high temperature regime, of cobalt nanowires (Co-NWs) having a hexagonal close-packed (HCP)... 相似文献
98.
In this paper, we introduce fuzzy mathematical programming (FMP) for decision-making related to software creation by selecting
optimal commercial-off-the-shelf (COTS) products in a modular software system. Each module in such software systems have different
alternatives with variations in their properties, for example, quality, reliability, execution time, size and cost. Due to
these variations, component-based software developers generally deals with the problem of selecting appropriate COTS products.
The development of COTS-based systems largely depends on the success of the selection process. Various crisp optimization
models of COTS products selection have been proposed in literature. However, in real COTS products selection problem, it is
difficult to estimate precisely the values of various model parameters due to lack of sufficient data and also because of
measurement errors. Hence, instead of crisp optimization model, if we use flexible optimization model then we might obtain
results which are more preferred by the decision maker. In this study, we use multiple methodologies such as quality model,
analytical hierarchy process and FMP to develop fuzzy multiobjective optimization model of the COTS products selection. To
determine a preferred compromise solution for the multiobjective optimization problem, an interactive fuzzy approach is used. 相似文献
99.
In this paper we present an expression relating the lattice thermal expansion coefficient αL (10−6 K−1) for the AIIIBV and AIIBVI semiconductors with the product of ionic charges (Z1Z2), melting temperature (Tm) and nearest neighbor distance d (Å). The lattice thermal expansion coefficient of these compounds exhibit a linear relationship when plotted on a log–log scale against the melting temperature (Tm), but fall on different straight lines according to the ionic charge product of the compounds. A good agreement has been found between the experimental and calculated values of the lattice thermal expansion coefficient for AIIIBV and AIIBVI semiconductors. 相似文献
100.
On the basis of the general framework of H-maximal monotonicity (also referred to as H-monotonicity in the literature), a generalization to Rockafellar’s theorem in the context of solving a general inclusion problem involving a set-valued maximal monotone operator using the proximal point algorithm in a Hilbert space setting is explored. As a matter of fact, this class of inclusion problems reduces to a class of variational inequalities as well as to a class of complementarity problems. This proximal point algorithm turns out to be of interest in the sense that it plays a significant role in certain computational methods of multipliers in nonlinear programming. The notion of H-maximal monotonicity generalizes the general theory of set-valued maximal monotone mappings to a new level. Furthermore, some results on general firm nonexpansiveness and resolvent mapping corresponding to H-monotonicity are also given. 相似文献