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11.
Electron energy distribution functions (EEDF) and related properties in the bulk region of the rf CO plasma at the reduced rf field frequency /p0=×107 sec–1 torr–1 have been calculated by solving the time-dependent spatially homogeneous Boltzmann equation in the presence of second-kind collisions and have been interpreted on a microphysical basis. The results show that second-kind collisions (vibrational and electronic) strongly affect the temporal evolution of EEDF, of the mean energy, and of the mean collision frequencies for vibrational and electronic excitation processes, as well as for ionization. In particular, second-kind collisions in the CO rf bulk plasma strongly decrease the modulation of the mean ionization frequency during its periodical alteration in the rf field. Furthermore, the effect of second-kind collisions on an approximate determination of the time-averaged EEDF in the rf bulk plasma using the so-called effective-field appriximation has been estimated.  相似文献   
12.
Experimental measurements of dew points for four methane + water mixtures between 2.6 2 10 5 Pa and 100.4 2 10 5 Pa and the temperature range from 225.5 K to 272.7 K were carried out. The experimental results were analysed in terms of both an equation of state model and an excess function-equation of state method, which reproduced the experimental data within AAD from 1.8 to 3.1 K and from 0.9 to 1.8 K, respectively.  相似文献   
13.
本文介绍了以X-射线衍射法测定非品区结构的径向分市函数RDF方法,并将其应用于聚苯乙烯(PS)非晶区的结构研究.  相似文献   
14.
Abstract

Programming environments such as S and Lisp-Stat have languages for performing computations, data storage mechanisms, and a graphical interface. These languages provide an interactive interface to data analysis that is invaluable. To take full advantage of these programming environments, statisticians must understand the differences between them. Ihaka and Gentleman introduced R, a version of S which uses a different scoping regimen. In some ways this makes R behave more like Lisp-Stat. This article discusses the concept of scoping rules and shows how lexical scope can enhance the functionality of a language.  相似文献   
15.
用伴随的方式给出了拟连续domain以及其Scott闭集格(又叫广义完全分配格)的等价刻画。此外,本文证明了拟连续格关于函数空间是不封闭的,从而不能构成cartesian闭范畴。  相似文献   
16.
We develop a simple theory of André-Quillen cohomology for commutative differential graded algebras over a field of characteristic zero. We then relate it to the homotopy groups of function spaces and spaces of homotopy self-equivalences of rational nilpotent CW-complexes. This puts certain results of Sullivan in a more conceptual framework.  相似文献   
17.
《Optimization》2012,61(4):335-350
We provide a theoretical basis for approximating the sensitivity of a perturbed solution and the local optimalvalue function, using information generated by a sequential unconstrained minimization technique in the normal course of solving a mathematical program. We show that various algorithmic sensitivity results can be obtained without other assumptions than those needed for the corresponding nonalgorithmic results. Our results extend the algorithmic calculation of sensitivity information introduced by Fiacco, utilizing the logarithmic barrier function and quadratic penalty function  相似文献   
18.

Spectrum problem with Riemann-Hilbert-Poincaré boundary condition is studied. This problem will lead to inhomogeneous Fuchsian differential equations with its right hand side depending on some constants to be determined simultaneously. We find out that the multiplicities of eigenfunctions for different eigenvalues are not necessary the same, which are in sharp contrast to the known results of Riemann-Hilbert problem for analytic functions.  相似文献   
19.

This paper studies the effectiveness of another kind of transposed sets of polynomials of one complex variable in closed regions, open discs, at the origin and for all entire functions. In addition, an upper bound for the order of these sets in this case is obtained.  相似文献   
20.
This note presents an efficient method for the routine solution of the subproblem associated with the Lagrangian dual of discrete programming problems having separable non-linear objective function and linear constraints. An additional advantage for subgradient methods is described.  相似文献   
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