Gain-scheduling through continuation of observer-based realizations-applications to H∞ and μ controllers

The dynamic behavior of gain scheduled controllers is highly depending on the state-space representations adopted for the family of lienar controllers designed on a set of operating conditions. In this paper, a technique for determining a set of consistent and physically motivated linear state-space transformations to be applied to the original set of linear controllers is proposed. After transformation, these controllers exhibits an-observer-based structure are therefore easily interpolted and implemented

Launcher attitude control: some additional design and optimization tools

This paper deals with the launcher attitude control during atmospheric flight. A two step approach combining an H1 control design and an optimization procedure is proposed. The first step is multi-objective stationary H1 design based on the Cross Standard Form. It provides easily a first rough solution from a few physical tuning parameters. The second step is a fine tuning using an multi-constraint satisfaction algorithm. This algorithm enables the certification criteria computed on the validation model to be met and is also used to propagate the nominal tuning to the full flight envelope

Lateral fligh control design for a highly flexible aircraft using a nonsmooth method

This paper describes a nonsmooth optimization technique for designing a lateral flight control law for a highly flexible aircraft. Flexible modes and high-dimensional models pose a major challenge to modern control design tools. We show that the nonsmooth approach offers potent and flexible alternatives in this difficult context. More specifically, the proposed technique is used to achieve a mix of frequency domain as well as time domain requirements for a set of different flight conditions

Launcher attitude control: discrete-time robust design and gain-scheduling

In this paper, a robust multi-objective design for the control of a launcher during atmospheric flight is investigated. This approach is based on the Cross Standard Form formulation which allows to incorporate the various specifications of the launcher problem in a streamlined manner. An important feature of this approach is that a non-conventional LQG/LTR approach, required to satisfy time-domain specifications, can be embedded into a more general standard problem in order to account for frequency-domain robustness constraints. The specific form of this standard problem is also very interesting for gain scheduling

A randomized placebo-controlled pilot study of the efficacy and safety of D-cycloserine in people with chronic back pain.

BACKGROUND: Few effective pharmacological treatment options exist for chronic back pain, the leading cause of disability in the US, and all are associated with significant adverse effects. OBJECTIVE: To determine the efficacy and safety of D-cycloserine, a partial agonist to the N-methyl-D-aspartate receptor, in the treatment of chronic low back pain. METHODS: A total of 41 participants with chronic back pain who met all inclusion and exclusion criteria were enrolled in a double-blind, placebo-controlled randomized pilot trial of D-cycloserine. Treatment was administered orally for six weeks at escalating daily doses of 100 mg, 200 mg, and 400 mg, each for two weeks. The primary outcome measure was back pain intensity using the Numeric Rating Scale (0-10). Secondary measures were back pain-related questionnaires: McGill Pain Questionnaire short form, painDETECT, PANAS, and BDI. The pre-specified analysis was a two-way repeated measures analysis of variance. RESULTS: A treatment difference was observed between groups treated with D-cycloserine and placebo at six weeks of 1.05 ± 3.1 units on the Numeric Rating Scale, with an effect size of 0.4 and p = 0.14. This trend of better chronic back pain relief with D-cycloserine was also observed in the secondary measures. No safety issues were seen. CONCLUSION: The difference in mean pain between the D-cycloserine and placebo groups did not reach statistical significance. However, a clinically meaningful effect size in the magnitude of pain relief was observed with a consistent pattern across multiple outcome measures with good safety, supporting further research into the effectiveness of D-cycloserine for chronic back pain

Observation and analysis of Fano-like lineshapes in the Raman spectra of molecules adsorbed at metal interfaces

Surface enhanced Raman spectra from molecules (bipyridyl ethylene) adsorbed on gold dumbells are observed to become increasingly asymmetric (Fano-like) at higher incident light intensity. The electronic temperature (inferred from the anti-Stokes (AS) electronic Raman signal increases at the same time while no vibrational AS scattering is seen. These observations are analyzed by assuming that the molecule-metal coupling contains an intensity dependent contribution (resulting from light-induced charge transfer transitions as well as renormalization of the molecule metal tunneling barrier). We find that interference between vibrational and electronic inelastic scattering routes is possible in the presence of strong enough electron-vibrational coupling and can in principle lead to the observed Fano-like feature in the Raman scattering profile. However the best fit to the observed results, including the dependence on incident light intensity and the associated thermal response is obtained from a model that disregards this coupling and accounts for the structure of the continuous electronic component of the Raman scattering signal. The temperatures inferred from the Raman signal are argued to be only of qualitative value.Comment: 20 pages, 12 figure