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International audienceThe work describes an automatically on-line self-tunable fuzzy inference system (STFIS) of a new configuration of mini-flying called XSF (X4 Stationnary Flyer) drone. A fuzzy controller based on on-line optimization of a zero order Takagi-Sugeno fuzzy inference system (FIS) by a back propagation-like algorithm is successfully applied. It is used to minimize a cost function that is made up of a quadratic error term and a weight decay term that prevents an excessive growth of parameters. Thus, we carried out control for the continuation of simple trajectories such as the follow-up of straight lines, and complex (half circle, corner, and helicoidal) by using the STFIS technique. This permits to prove the effectiveness of the proposed control law. Simulation results and a comparison with a static feedback linearization controller (SFL) are presented and discussed. We studied the robustness of the two controllers used in the presence of disturbances. We presented two types of disturbances, the case of a breakdown of an engine as well as a gust of wind

In this work, we present the temperature-dependence and time-resolved photoluminescence (PL) of CdS nanoparticles capped independently with three different ligands thiophenol, thioglycerol, and l-cysteine over a broad temperature range from 10 to 300 K. The respective nanoparticles sizes in the three systems studied in this work are 1.5, 4, and 2 nm as determined from X-ray diffraction (XRD). From the analysis of AFM images, it was found that the lateral particle sizes of capped CdS nanoparticles are greater than those deduced from XRD or optical absorption measurements. The aim of this study is the investigation of the impact of the organic ligands on the radiative recombination dynamics in organically capped CdS nanoparticles. From the PL study and based on the temperature-dependence and time-resolved emission spectroscopy, we conclude that the emission of CdS QDs film originates from recombination of the delocalized carriers in the internal core states with a small contribution of the localized carriers at the interface. The PL decay reveals a biexponential behavior for the entire three samples at all temperatures. One of the two exponential components decays rapidly with a time τ1 in the range 0.5–0.8 ns, whereas the other decays much more slowly, with a time τ2 in the range 1–3 ns. The weak activation energy (32–37 meV) deduced from the temperature dependence of the PL intensity suggests the involvement of shallow traps. The analysis of the experimental results reveals a relatively narrow size distribution, an efficient surface passivation, and a satisfactory thermal stability of CdS nanocrystals.

The radiative recombination of free excitons in diamond has been previously reported by Dean et al. /l/. They showed that the valence band splitting due to spin-orbit interaction must be taken into account for a good understanding of their line shape. Their experiments were performed a t high temperature (T > 77 K) and with a relatively low resolution.In our experiments we used a cathodoluminescence apparatus, working in pulsed mode, described in preceding publications /2, 3/. The main characteristics are briefly recalled: 2 z < 1 n s for 0 < I < 2 A/cm , rise time: pulse length 8 : 10 n s < 8 < 1000 ns, acceleration voltage U: 20 kV < U < 100 kV.We worked generally with the following experimental conditions: 2 I * 1.6 A/cm , U = 50 kV, repetition rate f = 800 Hz.High injection r a t e s can be reached, so that we could observe the free exciton luminescence a t low temperature, down to about 4.2 K. The intensity of this line decreases very quickly below 77 K. We worked with a sample of "natural diamond", type I1 b.On Fig, 1 is reported the main emission line of free excitons a t 80 K. The maximum is situated a t 5.275 eV, as previously observed by Dean et al. /l/.The width a t half height is much l a r g e r than predicted when the valence band split off by the spin-orbit interaction is neglected.