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81.
Alain Bensoussan Yiqun Li Sheung Chi Phillip Yam 《Stochastic Processes and their Applications》2018,128(2):644-688
In this article, we provide the first systematic study on the unique existence of the solution of backward stochastic dynamical variational inequalities on a general complete filtered probability space. We also build up a comprehensive analysis of the correspondence between these stochastic variational inequalities (resp. backward stochastic dynamics) and the weak solutions (instead of viscosity ones due to the intrinsic non-local nature of the integral of the gradient involved) of a class of non-local parabolic variational inequalities (resp. parabolic partial differential equations), which is barely touched in the existing literature due to its unconventional setting. 相似文献
82.
An edge cut X of a connected graph G is a k-restricted edge cut if G-X is disconnected and every component of G-X has at least k vertices. Additionally, if the deletion of a minimum k-restricted edge cut isolates a connected component of k vertices, then the graph is said to be super-λk. In this paper, several sufficient conditions yielding super-λk graphs are given in terms of the girth and the diameter. 相似文献
83.
Yves Renard 《Journal of Computational and Applied Mathematics》2010,234(3):906-923
The purpose of this paper is to present a new family of numerical methods for the approximation of second order hyperbolic partial differential equations submitted to a convex constraint on the solution. The main application is dynamic contact problems. The principle consists in the use of a singular mass matrix obtained by the mean of different discretizations of the solution and of its time derivative. We prove that the semi-discretized problem is well-posed and energy conserving. Numerical experiments show that this is a crucial property to build stable numerical schemes. 相似文献
84.
O. Moreno P. Sarriguren E. Moya de Guerra J.M. Udias T.W. Donnelly I. Sick 《Nuclear Physics A》2009,828(3-4):306-332
The influence of nuclear isospin mixing on parity-violating elastic electron scattering is studied for the even–even, N=Z nuclei 12C, 24Mg, 28Si, and 32S. Their ground-state wave functions have been obtained using a self-consistent axially-symmetric mean-field approximation with density-dependent effective two-body Skyrme interactions. Some differences from previous shell-model calculations appear for the isovector Coulomb form factors which play a role in determining the parity-violating asymmetry. To gain an understanding of how these differences arise, the results have been expanded in a spherical harmonic oscillator basis. Results are obtained not only within the plane-wave Born approximation, but also using the distorted-wave Born approximation for comparison with potential future experimental studies of parity-violating electron scattering. To this end, for each nucleus the focus is placed on kinematic ranges where the signal (isospin-mixing effects on the parity-violating asymmetry) and the experimental figure-of-merit are maximized. Strangeness contributions to the asymmetry are also briefly discussed, since they and the isospin mixing contributions may play comparable roles for the nuclei being studied at the low momentum transfers of interest in the present work. 相似文献
85.
The highly polar, nonvolatile N-nitrosamines, N-nitrosoproline and N-nitrosodiethanolamine, are determined by high-performance liquid Chromatographic separation with electrochemical detection using d.c. voltammetry, normal pulse voltammetry, and differential pulse voltammetry. The influence of flow rate and pulse time are determined, and detection limits on the order of 10-7 M are obtained. 相似文献
86.
We show that several terminating summation and transformation formulas for basic hypergeometric series can be proved in a straightforward way. Along the same line, new finite forms of Jacobi's triple product identity and Watson's quintuple product identity are also proved. 相似文献
87.
Wolf-Dieter Richter 《Journal of Mathematical Analysis and Applications》2007,336(2):1187-1202
Elementary trigonometric quantities are defined in l2,p analogously to that in l2,2, the sine and cosine functions are generalized for each p>0 as functions sinp and cosp such that they satisfy the basic equation p|cosp(φ)|+p|sinp(φ)|=1. The p-generalized radius coordinate of a point ξ∈Rn is defined for each p>0 as . On combining these quantities, ln,p-spherical coordinates are defined. It is shown that these coordinates are nearly related to ln,p-simplicial coordinates. The Jacobians of these generalized coordinate transformations are derived. Applications and interpretations from analysis deal especially with the definition of a generalized surface content on ln,p-spheres which is nearly related to a modified co-area formula and an extension of Cavalieri's and Torricelli's indivisibeln method, and with differential equations. Applications from probability theory deal especially with a geometric interpretation of the uniform probability distribution on the ln,p-sphere and with the derivation of certain generalized statistical distributions. 相似文献
88.
César Augusto Sangaletti Terçariol Rodrigo Silva González Alexandre Souto Martinez 《Physica A》2007,386(2):678-680
Consider a set of N cities randomly distributed in the bulk of a hypercube with d dimensions. A walker, with memory μ, begins his route from a given city of this map and moves, at each discrete time step, to the nearest point, which has not been visited in the preceding μ steps. After reviewing the more interesting general results, we consider one-dimensional disordered media and show that the walker needs not to have full memory of its trajectory to explore the whole system, it suffices to have memory of order lnN/ln2. 相似文献
89.
90.
T. I. Karu P. G. Kryukov V. S. Letokhov Yu. A. Matveetz V. A. Semchishen 《Applied Physics A: Materials Science & Processing》1981,24(3):245-247
The action of powerful pulsed picosecond radiation from a Nd: YAG laser (λ=530 nm, pulse energy: 0.01 J, intensity: 2GW/cm2) and an argon laser (λ=515 nm, power: 50 mW) on protoporphyrin-IX dimethylether in three solvents (trichlormethane, carbon
tetrachloride, dioxane) has been studied. Under continuous irradiation the quantum yield and resulting products do not differ
materially from the ones produced under mercury lamp irradiation. When irradiation is performed by powerful laser pulses of
picosecond duration the quantum yield of photodecomposition of protoporphyrin-IX dimethylether inereases substantially: by
10 in dioxane, by 4 in carbon tetrachloride and by 100 in trichlormethane. It is assumed that a quite different mechanism
of multistep excitation is responsible for photodecomposition under powerful picosecond pulses. 相似文献