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41.
Gheorghe Atanasiu 《manuscripta mathematica》1981,35(1-2):165-171
Ohne Zusammenfassung 相似文献
42.
43.
Petru Jebelean Gheorghe Moro?anu 《Journal of Mathematical Analysis and Applications》2006,313(2):738-753
This paper is concerned with the existence of solutions for the boundary value problem
44.
Given any maximal monotone operator ${A: D(A)\subset H \rightarrow 2^H}$ in a real Hilbert space H with ${A^{-1}(0) \ne \emptyset}$ , it is shown that the sequence of proximal iterates ${x_{n+1}=(I+\gamma_n A)^{-1}(\lambda_n u+(1-\lambda_n)(x_n+e_n))}$ converges strongly to the metric projection of u on A ?1(0) for (e n ) bounded, ${\lambda_n \in (0,1)}$ with ${\lambda_n \to 1}$ and γ n > 0 with ${\gamma_n \to\infty}$ as ${n \to \infty}$ . In comparison with our previous paper (Boikanyo and Moro?anu in Optim Lett 4(4):635–641, 2010), where the error sequence was supposed to converge to zero, here we consider the classical condition that errors be bounded. In the case when A is the subdifferential of a proper convex lower semicontinuous function ${\varphi :H \to (-\infty,+ \infty]}$ , the algorithm can be used to approximate the minimizer of φ which is nearest to u. 相似文献
45.
Mihai Mihăilescu Gheorghe Moroşanu 《Nonlinear Analysis: Real World Applications》2013,14(3):1466-1476
This paper investigates a nonlinear and non-homogeneous system of partial differential equations. The motivation comes from the fact that in a particular case the problem discussed here can be used in modeling the behavior of nonlinear Hencky-type materials. The main result of the paper establishes the existence of a nontrivial solution in an adequate functional space of Orlicz–Sobolev type by using Schauder’s fixed point theorem combined with adequate variational techniques. 相似文献
46.
In this paper we give a generalized form of the Schrödinger equation in the relativistic case, which contains a generalization of the Klein-Gordon equation. By complex Legendre transformation, the complex Lagrangian of electrodynamics produces a complex relativistic Hamiltonian H of electrodynamics, on the holomorphic cotangent bundle T′* M. By a special quantization process, a relativistic time dependent Schrödinger equation, in the adapted frames of (T′* M, H) is obtained. This generalized Schrödinger equation can be expressed with respect to the Laplace operator of the complex Hamilton space (T′*M, H). Finally, under some additional conditions on the proper time s of the complex space-time M and the time parameter t along the quantum state, by the method of separation of variables, we obtain two classes of solutions for the Schrödinger equation, one for the weakly gravitational complex curved space M, and the second in the complex space-time with Schwarzschild metric. 相似文献
47.
Gheorghe Daniela Neacsu Ana Contineanu Iulia Anghel Elena Maria Teodorescu Florina Chican Irina Elena Perisanu Stefan Tanasescu Speranta 《Journal of Thermal Analysis and Calorimetry》2019,138(2):1233-1242
Journal of Thermal Analysis and Calorimetry - A systematic thermodynamic study has been performed for a series of nitrates having cations derived from the α-amino acids glycine (Gly),... 相似文献
48.
The spectroscopic investigation of Tm3+ or (Nd, Yb, Tm)-doped Sc2O3 transparent ceramics, as laser-active media for visible and IR emission, was performed. The spectra are dominated by Tm3+ ions in sites of C2 symmetry and an energy level scheme and other spectral parameters were determined. The strong concentration quenching of 3H4 level emission in Tm:Sc2O3 at 300 K is discussed by considering the resonant cross-relaxation (3H4→3F4)?(3H6→3F4) process and multipolar interactions of various orders. The main energy-transfer processes leading to the blue upconversion emission from the 1G4 Tm3+ level in (Tm, Nd, Yb):Sc2O3 ceramic, under pulsed pumping at 808.3 nm were evidenced. 相似文献
49.
When a current is applied to a type-I superconducting strip containing a narrow channel across its width, magnetic flux spots nucleate at the edge and are then driven along the channel by the current. These flux "drops" are reminiscent of water drops dripping from a faucet, a model system for studying low-dimensional chaos. We use a novel high-bandwidth Hall probe to detect in real time the motion of individual flux spots moving along the channel. Analyzing the time series consisting of the intervals between successive flux drops, we find distinct regions of chaotic behavior characterized by positive Lyapunov exponents, indicating that there is a close analogy between the dynamics of the superconducting and water drop systems. 相似文献
50.
We present a model of gauge theory based on the symmetry group G×SU(2) where G is the gravitational gauge group and SU(2) is the internal group of symmetry. We employ the spacetime of four-dimensional Minkowski, endowed with spherical coordinates, and describe the gauge fields by gauge potentials. The corresponding strength field tensors are calculated and the field equations are written. A solution of these equations is obtained for the case that the gauge potentials have a particular form potentials induces a metric of Schwarzschild type on with spherical symmetry. The solution for the gravitational the gravitational gauge group space. 相似文献