In this paper we shall study vector cascade algorithms and refinable function vectors with a general isotropic dilation matrix in Sobolev spaces. By investigating several properties of the initial function vectors in a vector cascade algorithm, we are able to take a relatively unified approach to study several questions such as convergence, rate of convergence and error estimate for a perturbed...

Terahertz (1−10 THz, 30−300 μm) frequencies are among the least developed electromagnetic spectra even though they have wide ranging applications in spectroscopy, imaging, and remote sensing [1]. Since the report of quantum-cascade-lasers (QCLs) operating in the terahertz spectral region by Köhler et al. [2] there has been significant progress concerning the available frequencies, the temperatu...

A systematic optimization study of quantum cascade lasers with integrated nonlinearity for third-harmonic generation is performed. To model current transport the Pauli master equation is solved using a Monte Carlo approach. A multi-objective particle swarm optimization algorithm is applied to obtain the Pareto front. Our theoretical analysis indicates an optimized structure with five orders of ...

Training has increasingly turned into an important NGO tool for rural development in Asia and Africa. Such a use has made it essential to assess the impact of these training sessions. Again a good portion of these sessions are offered through cascades. There has been skepticism on the effectiveness of this mechanism. In response to the above need and skepticism, the paper assessed the effective...