Resonant thermal transport in semiconductor barrier structures

I report that thermal single-barrier (TSB) and thermal double-barrier (TDB) structures (formed, for example, by inserting one or two regions of a few Ge monolayers in Si) provide both a suppression of the phonon transport as well as a resonant-thermal-transport effect. I show that high-frequency phonons can experience a traditional double-barrier resonant tunneling in the TDB structures while the formation of Fabry-Perot resonances (at lower frequencies) causes quantum oscillations in the temperature variation of both the TSB and TDB thermal conductances $\sigma_{\text{TSB}}$ and $\sigma_{\text{TDB}}$.Comment: 4 pages. 4 figure.

The implications of service quality gaps for strategy implementation

This article addresses the problem of service quality strategy implementation and proposes three interrelated models: a static model of the organisation; a comprehensive dynamic model of the implementation process, both synthesised from the literature; and a mixed model, which integrates static and dynamic models. The mixed model is combined with the service quality gaps (SQGs) model, drawn at a previous congress paper, to propose a map of the pattern of SQGs occurring at each implementation stage; the organisational variables that can be manipulated to eliminate SQGs; and several implications to practising managers

Liapunov reachability and optimization in control

In this paper, we find sufficient conditions that do not rely upon any Liapunov stability results for the reachability of the target set by an admissible control from an a priori specified set of states. The conditions found are less restrictive than those obtained by Sticht, Vincent, and Schultz in Ref. 1. For control problems with specific integral performance index, we also show that, if a quantitative Liapunov function for optimization exists, then it may also serve as a qualitative Liapunov function ensuring the reachability of the target. The results are illustrated by examples