We study comprehensively using numerical simulations a new class of resonators, based on a circular photonic crystal reflector. The dependence of the resonator characteristics on the reflector design and parameters is studied in detail. The numerical results are compared to analytic results based on coupled mode theory. High quality factors and small modal volumes are found for a wide variety o...

This paper presents the control approach for single inverter dual coupled brushless DC motors (DCBLDC) drive system. One of the basic requirements of such systems, is the power balance between two motors and on the other hand, minimizing mechanical fluctuations in order to avoid mechanical equipment damage especially in the state of mechanical resonance. This paper also presents an improved for...

We report the operation of an optical in-well-pumped vertical-external-cavity surface-emitting laser. The laser delivers 1 W at 855 nm and is pumped with a cost-effective fiber-coupled laser diode emitting at 806 nm. The laser modal gain is examined and ways of optimizing the system are investigated and discussed.

Differential mode delay (DMD) modelling and measurements provide a means to characterise the modal structure of graded-index multimode fibres. In order to compute DMD output time pulses, we need to solve the modal propagation coefficients, modal group velocities and modal chromatic dispersion, compute the weighted modal amplitudes which are dependent on the excitation, and construct time pulses...

This paper presents an approach to extract implicit interpretations from modal constructions. Importantly, our approach uses a deterministic procedure to normalize eventualities and generate potential interpretations. An annotation effort demonstrates that these interpretations are intuitive to humans and most modal constructions convey at least one interpretation. Experimental results show tha...

This study addresses recent developments on the evaluation of multimode coupled bridge response and modeling of equivalent static wind loading on bridges when subjected to strong winds. First, the coupled bridge flutter is studied with an emphasis placed on the participation of structural modes in flutter, not only based on their amplitudes in flutter motion, but more importantly, by delving in...

In the present work, reformulation of dynamics a planar two-link manipulator has been presented in form joint errors and their derivatives. The linear second-order differential equations with time-varying coefficients represent Coupled Error Dynamics system. these equations, non-linear centrifugal Coriolis terms are expressed as functions error rates gravity function coefficients. After inclusi...

We analyze the coupling between the fundamental vector modal fields of two parallel polarization-maintaining fibers. An improved coupled-mode theory is employed, which also applies to anisotropic materials. Results for the array-mode-propagation constants are presented as a function of the relative tilt angle between the principal axes of the two fibers.

Rigorous coupled-wave analysis (also called the Fourier-modal method) is an efficient tool for the numerical analysis of grating diffraction problems. We show that, with only a few modifications, this method can be used efficiently for the numerical analysis of aperiodic diffraction problems, including photonic crystal waveguides, Bragg mirrors, and grating couplers. We thus extend the domain o...