We have developed open-source finite-element software for 2-D and 3-D dynamic and quasi-static modeling of crustal deformation. This software, PyLith 1.0, combines the quasi-static modeling functionality of PyLith 0.8 and its predecessors (LithoMop and Tecton) and the dynamic modeling functionality of EqSim. The target applications contain spatial scales ranging from tens of meters to hundreds ...

A new approach to gain scheduling linear dynamic controllers is illustrated on a pitch-axis autopilot design problem. In this application the linear controllers are designed at distinct operating conditions by H-Innnity methods. The gain scheduling procedure uses particular features of both the linear dynamic controllers and the controller connguration to remove so-called hidden coupling terms ...

In this paper, we discuss the scalability tuning of the HPC software framework FD4. The framework provides dynamic load balancing and model coupling for multiphase and multiphysics simulations. We first investigate scalability bottlenecks using the Vampir performance analysis tool-set on the BlueGene/Q system at JSC. Then, we describe and evaluate our optimized algorithms: A new hierarchical 1D...

The dynamic Stark effect due to a strong nonresonant but nonionizing laser field provides a route to quantum control via the creation of novel superposition states. We consider the creation of a field-free "switched" wave packet through adiabatic turn-on and sudden turn-off of a strong dynamic Stark interaction. There are two limiting cases for such wave packets. The first is a Raman-type coupl...

A numerical investigation on the dynamic large-signal analysis using a time-domain traveling wave model of quarter wave-shifted distributed feedback semiconductor lasers diode with a Gaussian distribution of the coupling coefficient (GDCC) is presented. It is found that the single-mode behavior and the more hole-burning effect corrections of quarter wave-shifted distributed feedback laser with ...

Abstract: The governing equations of motion for a drill string considering coupling between axial, lateral and torsional vibrations are obtained using a Lagrangian approach. The result leads to a set of non-linear equations with time varying coefficients. A fully coupled model for axial, lateral, and torsional vibrations of drill strings is presented. The bit/formation interactions are assumed ...

In this paper, we suggest a coupling of the description model of an embedded real-time multitasking application with a timed automata based model. The coupling purposes consists of providing the description model with operational semantic which uses communication channels and waiting point notions. In order to allow static verification of such kind of applications, we simulate its dynamic behav...

In an axisymmetric CO2-N2-H2O gas dynamic laser, let ? denote the intersection of the vertical plane of symmetry with the upper part of the (supersonic) nozzle. To obtain a maximal small signal gain, some authors have tested several families of curves for ?. To find the most general solution for ?, an application of Pontryagin’s principle led to the conjuncture that the optimal ? must consist o...

Atomic force microscope (AFM) has been developed at first for topography imaging; in addition, it is used for characterization of mechanical properties. Most researches have been primarily focused on rectangular single-beam probes to make vibration models simple. Recently, the U-shaped AFM probe is employed to determine sample elastic properties and has been developed to heat samples locally. I...

In this paper our objectives were to present the methodology and results for the experimental identification of two performance-limiting phenomena in a differential-based dual-input actuator testbed: (i) velocityand position-dependent friction and (ii) dynamic coupling between the dual inputs. The contributions of this paper are as follows: (i) experimental methodology to characterize the dynam...