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排序方式: 共有6721条查询结果,搜索用时 15 毫秒
991.
In this paper the existence, regularity and sharp estimates for the solutions of an abstract second order evolution equation are proved and applications to models of a (possibly non homogeneous) elastic beam with a frequency-proportional damping are given. 相似文献
992.
In this paper Tikhonov regularization for nonlinear illposed problems is investigated. The regularization term is characterized by a closed linear operator, permitting seminorm regularization in applications. Results for existence, stability, convergence and con- vergence rates of the solution of the regularized problem in terms of the noise level are given. An illustrating example involving parameter estimation for a one dimensional stationary heat equation is given. 相似文献
993.
AbstractWe provide a modified augmented Lagrange method coupled with a Tikhonov regularization for solving ill-posed state constrained elliptic optimal control problems with sparse controls. We consider a linear quadratic optimal control problem without any additional L2 regularization terms. The sparsity is guaranteed by an additional L1 term. Here, the modification of the classical augmented Lagrange method guarantees us uniform boundedness of the multiplier that corresponds to the state constraints. We present a coupling between the regularization parameter introduced by the Tikhonov regularization and the penalty parameter from the augmented Lagrange method, which allows us to prove strong convergence of the controls and their corresponding states. Moreover, convergence results proving the weak convergence of the adjoint state and weak*-convergence of the multiplier are provided. Finally, we demonstrate our method in several numerical examples. 相似文献
994.
Karl Michael Ortmann 《Central European Journal of Operations Research》2013,21(3):561-583
In this study, we consider positive cooperative TU games with finitely many players. We assume that all agents use the same scale. Furthermore, the worth that a coalition of players can achieve by cooperation is measured as a multiple of a defined standard base. In this multiplicative setting we characterise and analyse a solution concept which is related to the well known Shapley value. From a statistical point of view, the methodology allows computing relative importance of individual factors on the expected value. In particular, we present a specific application to general insurance pricing. As a result, the value may be used to analyse the business mix of an insurance portfolio by measuring exposure to risk factors. Similar applications refer to credit scoring and customer relationship management. In this sense, the modelling approach may be embedded as a risk analysis technique within a risk management framework. 相似文献
995.
996.
997.
In this paper, we prove both weak and strong convergence theorems for finding a common element of the solution set for a generalized equilibrium problem, the fixed point set of an asymptotically k-strict pseudo-contraction mapping in the intermediate sense, and the solution set of the variational inequality for a monotone and Lipschitz-continuous mapping by using a new hybrid extragradient method. Our results generalize and improve related results in the literatures. 相似文献
998.
In this paper, we presented new and important existence theorems of solution for quasi-equilibrium problems, and we show the uniqueness of its solution which is also a fixed point of some mapping. We also show that this unique solution can be obtained by Picard’s iteration method. We also get new minimax theorem, and existence theorems for common solution of fixed point and optimization problem on complete metric spaces. Our results are different from any existence theorems for quasi-equilibrium problems and minimax theorems in the literatures. 相似文献
999.
The current and the voltage of an X-pinch were measured. The inductance of the X-pinch was assumed to be a constant and estimated by the calculation of the magnetic field based on the well-known Biot-Savart's Law. The voltage of the inductance was calculated with L · di/dt and subtracted from the measured voltage of the X-pinch. Then, the resistance of the X-pinch was determined and the following results were obtained. At the start of the current flow the resistance of the exploding wires is several tens of Ohms, one order of magnitude, higher than the metallic resistance of the wires at room temperature, and then it falls quickly to about 1 , which reflects the physical processes occurring in the electrically exploding wires, i.e., a current transition from the highly resistive wire core to the highly conductive plasma. It was shown that the inductive contribution to the voltage of the X-pinch is less than the resistive contribution. For the wires we used, the wires' material and diameter have no strong influence on the resistance of the X-pinch, which may be explained by the fact that the current flows through the plasma rather than through the metallic wire itself. As a result, the current is almost equally divided between two parallel X-pinches even though the diameter and material of the wires used for these two X-pinches are significantly different. 相似文献
1000.
Mid-IR dual-wavelength difference frequency generation in uniform grating PPLN using index dispersion control 下载免费PDF全文
A novel widely tunable dual-wavelength mid-IR difference frequency generation (DFG) scheme with uniform grating periodically poled lithium niobate (PPLN) is presented in this paper. By using the temperature-dependent dispersion property of PPLN, the quasi-phase matching (QPM) peak for the pump may evolve into two separate ones and the wavelength spacing between them increases with the decrease of the crystal temperature. Such two pump QPM peaks may allow simultaneous dual-wavelength mid-IR laser radiations while properly setting the two fundamental pump wavelengths. With this scheme, mid-IR dual-wavelength laser radiations at around 3.228 and 3.548, 3.114 and 3.661, and 3.019 and 3.76 μm, are experimentally achieved for the crystal temperatures of 90, 65, and 30 ℃, respectively, based on the fiber laser fundamental lights. 相似文献