This paper investigates the problem of output feedback attitude control for rigid spacecraft subject to inertia matrix uncertainty, space disturbance, and input saturation. Firstly, a model transformation is adopted convert an system with immeasurable angular velocity into new system. All states converted are measurable available feedback; however, contains mismatched uncertainty resulting from...

This paper presents studies on applying the novel weak Galerkin finite element method (WGFEM) to a two-phase model for subsurface flow, which couples the Darcy equation for pressure and a transport equation for saturation in a nonlinear manner. The coupled problem is solved in the framework of operator decomposition. Specifically, the Darcy equation is solved by theWGFEM, whereas the saturation...

We present results on the eeect of geometrical boundary conditions on the stress distribution at the tip of cracks in mode I fracture. We have made molecular dynamics simulations on a 2-D triangular lattice of point masses connected by brittle Hookean springs. We study the connguration of the stress eld in rectangular shape lattices of diierent aspect ratios and with initial notches of varying ...

It is shown that current saturation in semiconducting carbon nanotubes is indistinguishable from metallic nanotubes if the carrier density is above a critical value determined by the bandgap and the optical phonon energy. This feature stems from the higher number of current-carrying states in the semiconducting tubes due to the van Hove singularity at the band edge. Above this critical carrier ...

In this letter, we propose a passivity-based control technique, where the resulting controllers can be interpreted as lag-compensators for nonlinear mechanical systems described in port-Hamiltonian framework. The proposed methodology considers dynamic controller such that relationship between input and error signal of interest expressed terms transfer function. Accordingly, gains tuned through ...

A brief review of the main physical results about the low temperature characterization and modeIing of Si CMOS devices is presented. More specifically, the carrier mobility law. the saturation velocity, the short channel effects, the impact ionization phenomenon. the hot carrier effects or the parasitic leakage current are physically discussed.

Three models for compositional ow in porous media, varying in physical and mathematical complexity, are considered. Various formulations of the governing equations that describe these models, including phase and global pressure-saturation formulations with the total velocity and ux, are presented. Finite element methods for solving these diierential formulations are identiied.

Seismic velocities in rocks at ultrasonic frequencies depend not only on the degree of saturation but also on the distribution of the fluid phase at various scales within the pore space. Two scales of saturation heterogeneity are important: (1) saturation differences between thin compliant pores and larger stiffer pores, and (2) differences between saturated patches and undersaturated patches a...

Ac-driven asymmetric pulses can be used to control the Fermi acceleration between three different motions, A: the accelerated mode, D: the decelerated mode, and H: the hyperaccelerated mode. In this paper we show that dissipation strongly affects the particles velocity, reducing the possibility for an accurate control of the dynamics. The saturation time, where the mean velocity starts to be co...