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Invariant Manifold Approach for the Stabilization of Nonholonomic Chained Systems: Application to a Mobile Robot 总被引:1,自引:0,他引:1
In this paper it is shown that a class ofn-dimensional nonholonomic chained systems can bestabilized using the invariant manifold approach. First, we derive aninvariant manifold for this class of systems and we show that, once onit, all the closed-loop trajectories tend to the origin under a linearsmooth time-invariant state feedback. Thereafter, it is shown that thismanifold can be made attractive by means of a discontinuoustime-invariant state feedback. Finally, a mobile robot is taken as anexample demonstrating the effectiveness of our study. 相似文献
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Benkhedda Mohammed Boufendi Toufik Tayebi Tahar Chamkha Ali J. 《Journal of Thermal Analysis and Calorimetry》2020,139(1):411-426
Journal of Thermal Analysis and Calorimetry - In the present paper, the first and second laws of thermodynamics are utilized to select the optimized position of porous insert to achieve maximum... 相似文献
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Determination of acesulfame and sucralose in oral electrolyte maintenance solution by liquid chromatography 总被引:3,自引:0,他引:3
A method was developed for the direct, simultaneous determination of acesulfame and sucralose in oral electrolyte maintenance solution (OEMS). Analyte separation and quantitation were achieved by gradient reversed-phase liquid chromatography (LC) and UV absorbance at 192 nm, respectively. Detection at a second wavelength, 214 nm, was used to check sucralose peak purity; 20 microL OEMS was injected without preparation or dilution. System linearity was demonstrated as 192 nm peak area versus analyte concentration at 80-120% OEMS sweetener fortification (r > 0.999, and all residuals < 0.5%, for both acesulfame and sucralose). Spike recoveries for OEMS samples prepared at 3 spiking levels (80, 100, and 120% sweetener fortification) ranged from 100.3 to 102.0% for acesulfame, and from 97.9 to 102.3% for sucralose. In a second assessment of method accuracy, the same spiked OEMS samples were tested by 2 alternative methods: acesulfame (LC/UV at 230 nm) and sucralose (anion exchange-pulsed amperometric detection). Results for the alternative acesulfame method were within 1.2%, and for the alternative sucralose method within 6.0%, of the corresponding results obtained by the 192 nm method. Repeatability and intermediate precision RSD values were < 1 % for acesulfame and < 3% for sucralose. The limits of quantitation were 1.6 and 32 mg/L for acesulfame potassium and sucralose, respectively. Despite the weak UV absorptivity of sucralose and the consequent small size of its LC peak, no evidence was found for sucralose interference in any of the commercial OEMS flavors. 相似文献
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Faezeh Farzaneh Leila Tayebi Mehdi Ghandi 《Reaction Kinetics and Catalysis Letters》2007,91(2):333-340
Vit-B12/ Al-MCM-41 catalyzed successfully the epoxidation either of cis or trans — stilbene with O2 as oxidant and isobutyraldehyde as co-reductant with 86–98% reactivity and 97–100% selectivity. Other olefins such as norbornene
and styrene undergo epoxidation reaction under similar conditions with good to fair selectivity. Details of the reactions
will be presented in this article. 相似文献
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Josefa Gomez Abdelhamid Tayebi Antonio del Corte Oscar Gutierrez Jose Manuel Gomez Francisco Saez de Adana 《Wireless Personal Communications》2013,72(4):2931-2944
A comparative study, based on three different measurements (direction of ray arrival, time difference of arrival and received signal strength), to compute the unknown position of mobile stations in indoor environments is presented in this paper. The comparison is carried out considering the results of analyses in a real building in Madrid. To overcome the problems that arise in indoor areas due to the presence of non line of sight conditions, the fingerprinting technique is applied in each of the cases. Data for computations are provided by a simulation tool based on the uniform theory of diffraction and ray-tracing techniques. This information is stored in the fingerprinting database and contains information related to every mobile station, every reference node and every access point located inside the environment under analysis. Experimental results compare the mean error when localizing several mobile stations by using the three different approaches. The goal is to obtain high precision in the localization by means of alternative methods to the received signal strength classical measurement. These techniques will be useful in critical environments where high operational security requirement are demanded. 相似文献
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E. Peyghan A. Tayebi A. Ahmadi 《Journal of Mathematical Analysis and Applications》2012,391(1):159-169
The Cauchy problem of the Landau equation with potential forces on torus is investigated. The global existence of solutions with the symmetry of origin and the exponential convergence rate in time to the steady state are obtained for any initially smooth, periodic, origin symmetric small perturbation. 相似文献
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In this Note, we prove that every m-th root Finsler metric with isotropic Landsberg curvature reduces to a Landsberg metric. Then, we show that every m-th root metric with almost vanishing H-curvature has vanishing H-curvature. 相似文献
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A. Tayebi A. Nankali E. Peyghan 《Journal of Contemporary Mathematical Analysis (Armenian Academy of Sciences)》2014,49(4):184-193
We prove that every m-th root metric with isotropic mean Berwald curvature reduces to a weakly Berwald metric. Then we show that an m-th root metric with isotropic mean Landsberg curvature is a weakly Landsberg metric. We find necessary and sufficient condition under which conformal β-change of anm-th root metric is locally dually flat. Finally, we prove that the conformal β-change of locally projectively flat m-th root metrics are locally Minkowskian. 相似文献
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Lobat Tayebi Masoud Mozafari Rita El‐khouri Parvaneh Rouhani Daryoosh Vashaee 《Photochemistry and photobiology》2014,90(3):517-521
Light induced cis/trans isomerization in the family of merocyanine (MC) dyes offers a recyclable proton pumping ability which can potentially be used in hybrid bio‐electronic devices. In this article, a hexadecyl MC dye is embedded in lipid molecules to make a macromolecular configuration of a lipid/hexadecyl MC membrane. Lipid molecules play a critical role in stabilizing the dye in a membrane structure for practical use in energy devices. In this study, we first examined the proton pumping characteristic of the lipid/hexadecyl MC membrane in a conventional photoelectrochemical cell. Next, a major modification in the cell was introduced by eliminating I2/I‐electrolyte which resulted in a two‐fold increase in the open circuit voltage compared with that of the conventional cell. In addition, the charging time in the new cell was reduced approximately four orders of magnitude. This research demonstrated that the newly designed lipid‐ MC cell can act as a promising bioelectronic device based on the green energy of photoinduced MC dye proton pumping. 相似文献