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991.
P. Anselmann W. Hampel G. Heusser J. Kiko T. Kirsten E. Pernicka R. Plaga U. R?nn M. Sann C. Schlosser et al. 《Il Nuovo Cimento C》1992,15(6):917-929
Summary The GALLEX collaboration is performing an experiment for the detection of neutrinos coming principally from the p-p fusion
reaction in the Sun, via the reaction νe+71Ga→71Ge+e−. The experiment is running in the Gran Sasso Underground Laboratory of INFN, using as a target 30.3 tons of gallium in the
form of 8.13 molar aqueous GaCl3 solution.
A report is given of the status of GALLEX after the end of the operations devoted to the removal from the solution of the
cosmogenically formed Ge isotopes, completed in the middle of 1991. The experiment is now collecting data on solar neutrinos
and the data analysis is in progress. Preliminary results concerning the first year of measurement are presented.
Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990. 相似文献
992.
用线性变换方法推导了二维正方结构正n边形直柱光子晶体的带隙计算公式.采用线性变换方法可以简单地处理平面波展开方法中ε-1(r)的Fourier变换系数,使得相应的带隙计算变得简单有效.在固定填充率f=04的情况下,计算了砷化镓(ε=114)材料的正n边形直柱光子晶体带隙结构.发现随着n的增加,光子晶体的对称性相应提高,最大带隙的大小出现单调下降趋势.当n趋向于无穷大的时候,计算的正n边形直柱光子晶体的带隙趋向于零,与圆柱的情况完全相符.
关键词:
平面波展开方法
线性变换
正n边形直柱
带隙
对称性 相似文献
993.
基于联系数复运算的区间数多属性决策方法及应用 总被引:8,自引:4,他引:4
针对属性权重与属性值都为区间数的多属性决策问题,先把区间数转换成a+bi形式的联系数,再按联系数的复运算要求改写成三角函数表达式,在此基础上得到一种多属性加权决策综合主值模型.实例应用表明:该方法在一定程度上客观地反映出区间数多属性决策问题中确定性与不确定性的相互联系和相互影响,算法简便,结论可靠. 相似文献
994.
S. Li G. I. Shishkin L. P. Shishkina 《Computational Mathematics and Mathematical Physics》2007,47(3):442-462
A problem for the black-Scholes equation that arises in financial mathematics is reduced, by a transformation of variables,
to the Cauchy problem for a singularly perturbed parabolic equation with the variables x, t and a perturbation parameter ɛ, ɛ ∈ (0, 1]. This problem has several singularities such as the unbounded domain, the piecewise
smooth initial function (its first-order derivative in x has a discontinuity of the first kind at the point x = 0), an interior (moving in time) layer generated by the piecewise smooth initial function for small values of the parameter
ɛ, etc. In this paper, a grid approximation of the solution and its first-order derivative is studied in a finite domain including
the interior layer. On a uniform mesh, using the method of additive splitting of a singularity of the interior layer type,
a special difference scheme is constructed that allows us to ɛ-uniformly approximate both the solution to the boundary value
problem and its first-order derivative in x with convergence orders close to 1 and 0.5, respectively. The efficiency of the constructed scheme is illustrated by numerical
experiments.
The text was submitted by the authors in English. 相似文献
995.
Jie Sun 《Mathematical Programming》1993,60(1-3):69-79
This paper presents a theoretical result on convergence of a primal affine-scaling method for convex quadratic programs. It is shown that, as long as the stepsize is less than a threshold value which depends on the input data only, Ye and Tse's interior ellipsoid algorithm for convex quadratic programming is globally convergent without nondegeneracy assumptions. In addition, its local convergence rate is at least linear and the dual iterates have an ergodically convergent property.Research supported in part by the NSF under grant DDM-8721709. 相似文献
996.
Nobuaki Kuroki 《Fuzzy Sets and Systems》1982,8(1):71-79
In this paper we shall introduce the notion of fuzzy semiprimality in a semigroup, which is an extension of semiprimality in it, and characterize a semigroup that is a semilattice of simple semigroups in terms of fuzzy semiprimality. 相似文献
997.
Complex-valuedVector-matrixMultiplicationArchitecture¥ZHOUChanghe;LIULiren(ShanghaiInstituteofOpticsandFineMechanics,Academia... 相似文献
998.
本文考虑一类半线性椭圆型方程的边界层-角层现象,在适当的条件下,我们得到了摄动问题解的存在性及其一致有效渐近展开式. 相似文献
999.
In this paper, a new data processing and calibration method for a pronunciation system of an eye-tracking device is described. The eye-tracking device was created using both head mounted display (HMD) technology and remote operation capabilities. A pattern recognition computer program was used to distinguish the pupil position and calculate its coordinates.This system can be adapted to provide a digital speech function. A new method for processing the image of the eye in the PC-based system was also developed. With one video CCD camera and frame grabber analyzing a series of human pupil images while the subject is gazing at the screen, an auto-calibration algorithm is used to obtain the direction of the eye gaze in real time. The computers provide the speech sound according to the location where the eye gazes exceed 0.5 s. The availability of multipurpose in this eye-tracking system with very simple equipment will be reconfirmed for future advanced research. 相似文献
1000.
Kurt M. Anstreicher 《Mathematical Programming》1988,41(1-3):367-373
In this note we report a simple characteristic of linear programming central trajectories which has a surprising consequence. Specifically, we show that given a bounded polyhedral setP with nonempty interior, the logarithmic barrier function (with no objective component) induces a vector field of negative Newton directions which flows from the center ofP, along central trajectories, to solutions of every possible linear program onP. 相似文献