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71.
The solution of a generalized non-relativistic Schrödinger equation with radial potential energy V(r)=V 0(r/a 0)2–2 is presented. After reviewing the general properties of the radial ordinary differential equation, power series solutions are developed. The Green's function is constructed, its trace and the trace of its first iteration are calculated, and the ability of the traces to provide upper and lower bounds for the ground eigenvalue is examined. In addition, WKB-like solutions for the eigenvalues and eigenfunctions are derived. The approximation method yields valid eigenvalues for large quantum numbers (Rydberg states).  相似文献   
72.
Binary excess molar volumes, V m E, have been evaluated from density measurements, using a vibrating tube densimeter over the entire composition range for binary liquid mixtures of ionic liquids 1-ethyl-3-methyl-imidazolium diethyleneglycol monomethylethersulphate [EMIM]+[CH3(OCH2CH2)2OSO3] or 1-butyl-3-methyl-imidazolium diethyleneglycol monomethylethersulphate [BMIM]+[CH3(OCH2CH2)2OSO3] or 1-methyl-3-octyl-imidazolium diethyleneglycol monomethylethersulphate [MOIM]+[CH3(OCH2CH2)2OSO3]+methanol and [EMIM]+[CH3(OCH2CH2)2OSO3]+water at 298.15, 303.15 and 313.15 K. The V m E values were found to be negative for all systems studied. The V m E results are explained in terms of intermolecular interactions and packing effects. The experimental data were fitted by the Redlich-Kister polynomial.  相似文献   
73.
We adapt a construction due to Troesch to the category of strict polynomial superfunctors in order to construct complexes of injective objects whose cohomology is isomorphic to Frobenius twists of the (super)symmetric power functors. We apply these complexes to construct injective resolutions of the even and odd Frobenius twist functors, to investigate the structure of the Yoneda algebra of the Frobenius twist functor, and to compute other extension groups between strict polynomial superfunctors. By an equivalence of categories, this also provides cohomology calculations in the category of left modules over Schur superalgebras.  相似文献   
74.
《Discrete Mathematics》2022,345(7):112796
We introduce the active partition of the ground set of an oriented matroid perspective (or morphism, or quotient, or strong map) on a linearly ordered ground set. The reorientations obtained by arbitrarily reorienting parts of the active partition share the same active partition. This yields an equivalence relation for the set of reorientations of an oriented matroid perspective, whose classes are enumerated by coefficients of the Tutte polynomial, and a remarkable partition of the set of reorientations into Boolean lattices, from which we get a short direct proof of a 4-variable expansion formula for the Tutte polynomial in terms of orientation activities. This formula was given in the last unpublished preprint by Michel Las Vergnas; the above equivalence relation and notion of active partition generalize a former construction in oriented matroids by Michel Las Vergnas and the author; and the possibility of such a proof technique in perspectives was announced in the aforementioned preprint. We also briefly highlight how the 5-variable expansion of the Tutte polynomial in terms of subset activities in matroid perspectives comes in a similar way from the known partition of the power set of the ground set into Boolean lattices related to subset activities (and we complete the proof with a property which was missing in the literature). In particular, the paper applies to matroids and oriented matroids on a linearly ordered ground set, and applies to graph and directed graph homomorphisms on a linearly ordered edge-set.  相似文献   
75.
Burgers方程是一类应用广泛的非线性偏微分方程,方程中的非线性项难以处理。该文提出一种新的时空多项式配点法——多项式特解法求解三维Burgers方程。求解过程分为两步:第一步,对三维Burgers方程中的线性导数项(包括时间导数项),求出相应的多项式特解。第二步,将求出的多项式特解作为基函数,对三维Burgers方程中剩余的非线性项进行迭代求解。与时空多项式函数作为基函数对三维Burgers方程进行直接求解相比,该算法简单易行,得到的近似解精度非常高,算法极其稳定,对于教学过程中提高学生的编程能力,加深对高维Burgers方程的理解能力以及Burgers方程的实际应用具有重要意义。  相似文献   
76.
令X=(n1,n2,…,nt),Y=(m1,m2,…,mt)是两个t维递减序列.如果对所有的j,1≤j≤t,都有∑i=1~j、ni≥∑i=1~j mi以及∑i=1~t ni=∑i=1~t mi,则称X可盖Y,记作X■Y.如果X≠Y,则记作X■Y.本文考虑联图G(n1,n2,…,nt;a)=(Kn1n2∪…∪Knt)∨Ka的谱半径,这里n1+n2+…+nt+a=n,(n1,n  相似文献   
77.
In this paper, we consider the weighted local polynomial calibration estimation and imputation estimation of a non-parametric function when the data are right censored and the censoring indicators are missing at random, and establish the asymptotic normality of these estimators. As their applications, we derive the weighted local linear calibration estimators and imputation estimations of the conditional distribution function, the conditional density function and the conditional quantile function, and investigate the asymptotic normality of these estimators. Finally, the simulation studies are conducted to illustrate the finite sample performance of the estimators.  相似文献   
78.
Slowly time-varying delays are seldom, but do need to be, considered in the context of discrete-time systems. This paper addresses the exponential stability issue of discrete-time systems with slowly time-varying delays. The basic idea is to transform, by utilizing the switching transformation approach, the original system with slowly time-varying delays into an equivalent switched system with special switching signal. Different types of delays correspond to different types of switching signals, and the stability issue of the original system is converted into that of a switched system. It is the first time that the method of switched homogeneous polynomial Lyapunov function is applied to general delayed systems. Some sufficient exponential stability conditions for the original system are proposed in several situations. It is numerically shown that the conservativeness of the proposed conditions reduces as the degree of the switched homogeneous polynomial Lyapunov function increases.  相似文献   
79.
A necessary condition for the asymptotic normality of the sample quantile estimator isf(Q(p))=F(Q(p))>0, whereQ(p) is thep-th quantile of the distribution functionF(x). In this paper, we estimate a quantile by a kernel quantile estimator when this condition is violated. We have shown that the kernel quantile estimator is asymptotically normal in some nonstandard cases. The optimal convergence rate of the mean squared error for the kernel estimator is obtained with respect to the asymptotically optimal bandwidth. A law of the iterated logarithm is also established.This research was partially supported by the new faculty award from the University of Oregon.  相似文献   
80.
ONBAHADURASYMPTOTICEFFICIENCYINASEMIPARAMETRICREGRESSIONMODELLIANGHUA(梁华);CHENGPING(成平)(InstituteofSystemsScience,theChineseA...  相似文献   
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