One of the ongoing issues with time fractional diffusion models is the design of efficient high-order numerical schemes for the solutions of limited regularity. We construct in this paper two efficient Galerkin spectral algorithms for solving multi-dimensional time fractional advection–diffusion–reaction equations with constant and variable coefficients. The model solution is discretized in time with a spectral expansion of fractional-order Jacobi orthogonal functions. For the space discretization, the proposed schemes accommodate high-order Jacobi Galerkin spectral discretization. The numerical schemes do not require imposition of artificial smoothness assumptions in time direction as is required for most methods based on polynomial interpolation. We illustrate the flexibility of the algorithms by comparing the standard Jacobi and the fractional Jacobi spectral methods for three numerical examples. The numerical results indicate that the global character of the fractional Jacobi functions makes them well-suited to time fractional diffusion equations because they naturally take the irregular behavior of the solution into account and thus preserve the singularity of the solution.
Sinusoidal magnetic fields with strengths as small as ~0.5 nT (RMS) and frequencies of 5 -100 Hz have been detected at room temperature by modulating the magneto-optical Kerr response of epitaxial rare earth-iron garnet films. Ferromagnetic nanoparticles with a mean size of 500 nm have also been detected in real time in a liquid flow stream at field strengths as low as 1 muT. 相似文献
Wireless Personal Communications - In this paper, an energy efficient precoding scheme is proposed for massive multiple-input multiple-output (MIMO) systems. The proposed precoding scheme... 相似文献
This paper presents a solution for the formation flight problem for multiple unmanned aerial vehicles (UAVs) cooperating to execute a required mission. Learning Based Model Predictive Control (LBMPC) is implemented on the team of UAVs in order to accomplish the required formation. All flight simulations respect Reynold's rules of flocking to avoid UAV collisions with nearby flockmates, match the team members velocity and stay close to each other during the formation. The main contribution of this paper lies in the application of LBMPC to solve the problem of formation for an autonomous team of UAVs. The proposed solution is theoretically, by the application of analysis to the problem, demonstrated to be stable. Moreover, simulations support the findings of the paper. The main contributions of this paper are the proposed LBMPC formulation for formation of vehicles with uncertainty in their models, and the theoretical analysis of the solution. 相似文献
Conductance measurements are reported for S-t-buisBr, S-n-buisBr, S-n-amisBr, and S-n-octisBr in pure water and in water-dioxane mixtures at 25°C in the dielectric constant range 13 < D < 78.5. The data were analyzed by the Fuoss—Onsager equation for associated electrolytes and the characteristic functions are derived. A trial to obtain the transport number of the Br? ion is described. The hydrodynamic radius is calculated for Br? ion and for each of the four cations. Finally the association constant KA is analyzed on the basis of the solvent separated-ion pair model. 相似文献