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171.
Sacha Bernet Christophe Cudel Damien Lefloch Michel Basset 《Machine Vision and Applications》2013,24(2):393-406
This paper presents new methods to calibrate a head-mounted Eye Tracker (ET) automatically, as well as a new way to obtain an estimated point of regard (POR), taking account of the parallax. Calibration is performed in real time; it is easy for the user who just needs to look at one calibration pattern for a few seconds before starting. This method provides a very important couple of points which helps to use a local relationship to compute the POR instead of a global one. This approach significantly improves the precision of the points of regard when the scene camera is mounted with a short focal lens. An estimation of POR when the user looks somewhere outside the calibration distance is also proposed. This estimation is based on an ET modelling such as a stereovision system, to take account of the parallax effect. The aim of this study is to simplify the use of ET techniques for “non-initiated” people, especially here learner drivers. 相似文献
172.
Franois‐Xavier Legrand Natacha Six Christian Slomianny Herv Bricout Sbastien Tilloy Eric Monflier 《Advanced Synthesis \u0026amp; Catalysis》2011,353(8):1325-1334
A new triphenylphosphane based on a β‐cyclodextrin skeleton (PM‐β‐CD‐OTPP) was synthesized. This ligand can be dispersed in water by using the nanoprecipitation method. Transmission electron microscopy and NMR spectroscopy showed that PM‐β‐CD‐OTPP is aggregated in water and forms a stable dispersion. Its aqueous solubility can be dramatically increased in the presence of selected water‐soluble guests by formation of inclusion complexes. Associated to a rhodium precursor, PM‐β‐CD‐OTPP is able to generate soluble rhodium species in water. In addition, NMR experiments showed that the cyclodextrin cavity remains accessible for a guest even when PM‐β‐CD‐OTPP is coordinated to rhodium. Finally, this ligand was efficient for rhodium‐catalyzed hydrogenation and hydroformylation performed in aqueous medium. 相似文献
173.
Multilayer woven reinforcements are increasingly employed in the domain of composite materials. Delamination occurrence and resultant failure of a laminated composite piece subjected to high vibrations, is an issue of much concern in aeronautics. The situation becomes more complex in case of bended/curved pieces. In order to improve through the thickness mechanical properties, 3D-woven multilayer interlock fabric is used as composite reinforcement. Structural changes, i.e. thickness change, relative slippage of layers, change in tow aspect ratio and change of orientation of the tows columns, etc. occur in such fabrics during the forming process. These changes may lead to the gradient of the resin amount in composite, internal stresses and variations of mechanical properties in the piece. No significant research has been conducted on this aspect. Lack of knowledge or neglecting these changes may lead to prejudicial estimations of ultimate mechanical properties and fracture analysis. In the present article, the changes that occurred in 5-layer and 13-layer 3D-woven multilayer interlock fabrics have been studied, when moulded at five different angles and two different bending radii. A significant change in thickness, tow aspect ratio, tow orientation and relative layer slippage is observed. 相似文献
174.
A. Kahouli A. Sylvestre F. JomniE. André J.-L. GardenB.Yangui B. BergeJ. Legrand 《Thin solid films》2012,520(7):2493-2497
Using dielectric spectroscopy analysis, three relaxation mechanisms have been identified in 60% semi-crystalline parylene AF4 ([-F2C-C6H4-CF2-]n) fluoropolymers. At high temperature, fluorine species located at the electrode/polymer interface involve a space-charge polarization. β-Process assigned to local molecular motions of the C-F dipoles and the γ-relaxation due to local fluctuations of the F2C-C6H4 groups are also evidenced at intermediate and cryogenic temperatures respectively. Space-charge fluorine F−, β and γ relaxations obey an Arrhenius law against temperature with activation energy Ea (F−) = 1.26 eV, Ea (β) = 0.59 eV and Ea (γ) = 0.29 eV. 相似文献
175.
176.
177.
C. Legrand T. Haccart G. Velu D. Chambonnet D. Remiens L. Burgnies F. Mehri J. C. Carru 《Microelectronics Reliability》1999,39(2):251
This paper describes some experimental results concerning the dielectric characterizations of PZT, PT and BT ferroelectric thin films deposited on silicon. Firstly, the ferroelectric properties of these films are checked, notably the high dielectric constant values. Secondly, assuming a simple electrical model, we derive from impedance measurements the conductivity of the platinum deposited as a bottom electrode. 相似文献
178.
A. Sibai S. Lhostis Y. Rozier O. Salicio S. Amtablian C. Dubois J. Legrand J.P. Snateur M. Audier L. Hubert-Pfalzgraff C. Dubourdieu F. Ducroquet 《Microelectronics Reliability》2005,45(5-6):941
SrTiO3 thin films (STO), were deposited on Si(100) covered by 2 nm of SiO2, at different temperatures from 450 °C to 850 °C using liquid injection MOCVD, the bimetallic precursor being Sr2Ti2(OiPr)8(tmhd)4. The STO films were analysed by XRD, FTIR, SIMS and TEM. An amorphous layer was observed between STO and SiO2/Si. The nature and thickness of the interlayer were determined, as well as the most favourable conditions for a good quality crystalline STO film, and a reduced interlayer. 相似文献
179.
Philippe Basset Andreas Kaiser Bernard Legrand Dominique Collard Lionel Buchaillot 《Mechatronics, IEEE/ASME Transactions on》2007,12(1):23-31
This paper proposes a successful asynchronous remote powering and control of electrostatic microactuators, organized in two distributed micro motion systems (DMMS) with the aim of realizing a wireless microrobot. Remote powering of the integrated circuit (IC) and the microelectromechanical systems (MEMS) components is obtained by inductive coupling at 13.56 MHz, and the digital transmission is created by modulating the carrier amplitude by 25%. The system includes a high-voltage controller IC. It provides a link between the power and data on the receiver antenna on one side, and the actuators of the microrobot on the other. The micromachined antenna is designed to optimize the inductive coupling. The main IC building blocks, such as the received signal rectifier/amplifier, the integrated digital processing and the DMMS actuation voltage generation are given in detail. The demonstrator has successfully achieved the remote control and asynchronous operation under 100 V of two arrays of 1700 electrostatic actuators, having a capacity of 2 nF each 相似文献
180.
In(1LR)pn2a is a pericentric inversion with a euchromatic breakpoint in the 2E polytene region and a heterochromatic breakpoint in the right arm of the X chromosome. It is associated with position-effect variegation (PEV) of the pn, wapl, Pgd and other vital loci of the 2E region, which are relocated near the bulk of the X heterochromatin. Cytological analysis showed that the rearrangement brings the 1A-2E euchromatic segment directly into contact with a major portion of the h34 block, a heterochromatic region that is positively stained by the N-banding technique and contains the AAGAG satellite sequences. Molecular cloning revealed the presence of a new junction between euchromatin and AAGAG satellite sequences and demonstrated that the euchromatic breakpoint of In(1LR)pn2a lies in the vinculin gene. In the X ray-induced secondary rearrangement In(1LR)r30, consisting of a pericentric inversion superimposed on In(1LR)pn2a, the h34 material remains associated with the 2E region but is separated from the rest of the X heterochromatin. In this case, the pn, wapl and Pgd loci no longer variegate, suggesting that the satellite-containing h34 region is not able per se to induce detectable PEV on the adjacent euchromatic genes. 相似文献