This paper presents a sliding mode controller for a “Soft” 2-DOF Planar Pneumatic Manipulator actuated by pleated pneumatic
artificial muscle actuators. Since actuator dynamics is not negligible, an approximate model for pressure dynamics was taken
into account, which made it necessary to perform full input-output feedback linearization in order to design a sliding mode
controller. The design of the controller is presented in detail, and experimental results obtained by implementing the controller
are discussed
Published in Prikladnaya Mekhanika, Vol. 44, No. 10, pp. 135–144, October 2008. 相似文献
The European Commission produced and certified uranium glass for fission-track dating in 1996 (Reference Material IRMM-540). This material is now out of stock and a project for the preparation of two new reference glasses is underway. The new glasses, containing nominally 15 and 55 mgkg−1 uranium, were prepared from blended oxide powder, and cast using an improved method, which minimised micro-scale defects and optimised the yield. Glass rods were produced which were then cut into discs of 2 mm thickness and 15 mm diameter and subsequently polished.
Uranium homogeneity and fission-track stability are critical properties of the glass. An extensive study was carried out to verify the homogeneity by fission-track counting, investigating both within-disc and between disc effects, and to investigate potential track fading due to thermal annealing. No evidence of uranium heterogeneity was detected. The stability study, using an “isochronous” method, in which all measurements are made at the end of exposure to artificial ageing, is still underway.
The reference material will be certified for isotopic composition (natural), uranium mass fraction and neutron fluence (one disc out of each set of three will be irradiated, together with a mica foil, to induce fission tracks in a certified fluence). The reference materials will be released as IRMM-540R (15 mgkg−1 U) and IRMM-541 (55 mgkg−1 U). 相似文献
We report the development of an atomic decomposition method of the protein solvation free energy in water, which ascribes global change in the solvation free energy to local changes in protein conformation as well as in hydration structure. So far, empirical decomposition analyses based on simple continuum solvation models have prevailed in the study of protein-protein interactions, protein-ligand interactions, as well as in developing scoring functions for computer-aided drug design. However, the use of continuum solvation model suffers serious drawbacks since it yields the protein free energy landscape which is quite different from that of the explicit solvent model and since it does not properly account for the non-polar hydrophobic effects which play a crucial role in biological processes in water. Herein, we develop an exact and general decomposition method of the solvation free energy that overcomes these hindrances. We then apply this method to elucidate the molecular origin for the solvation free energy change upon the conformational transitions of 42-residue amyloid-beta protein (Aβ42) in water, whose aggregation has been implicated as a primary cause of Alzheimer's disease. We address why Aβ42 protein exhibits a great propensity to aggregate when transferred from organic phase to aqueous phase. 相似文献
Abstract A number of polyurethanes were synthesized by reacting castor oil with isophorone diisocyanate while varying the NCO/OH ratio. All these polyurethanes were reacted with such acrylic monomers as acrylamide and methacrylamide by using ethylene glycol dimethacrylate as a crosslinker and benzoyl peroxide as the initiator. The physicochemical properties of interpenetrating polymer networks (IPNs) are reported. The durability, solvent absorption, outdoor weathering, and aging properties of IPNs have been studied. Thermogravimetric analysis was used to study the thermal behavior of IPNs and the evaluation of kinetic parameters. A number of equations, such as those of Freeman-Anderson, Broido, Piloyan-Novikova, Horowitz-Mitzger, and Coats-Redfern, have been used to determine the kinetic parameters. The degradation mechanism is discussed. 相似文献
Photoelectron spectra obtained by He(I) and He(II) excitation of glycine, sarcosine and glycine methyl ester are presented. The p-type bands in the He(I) spectrum of glycine are interpreted in terms of localized molecular orbitals; the C 2s bands are identified in the He(II) spectrum. He(I) spectra of some N-acetylamino acids and of a variety of α-and ω-substituted amino acids are also reported. 相似文献
Variations in the ratio of monomer/excimer emissions from pyrenyl groups bound to a calix[4]arene through facing carboxamidomethyl substituents have been investigated in H2O/CH3CN mixtures. Above a level of 50% H2O, monomer emission declines and the excimer emission concomitantly increases. DFT calculations support the argument that disruption of intramolecular NHO bonds by water results in a geometry, which favors contact of the pyrene units and thus a strong excimer emission. Addition of Fe(III) to a H2O/CH3CN (4:1, v/v) solution of 1 at pH 6.1 quenches both monomer and excimer emissions through electron transfer (eT) from excited pyrene to the metal ion. 相似文献
Transition metal phosphides (TMPs) as ever-evolving electrocatalytic materials have attracted increasing attention in water splitting reactions owing to their cost-effective, highly active and stable catalytic properties. This work presents a facile synthetic route to NiCoP nanoparticles with Ru dopants which function as highly efficient electrocatalysts for oxygen evolution reaction (OER) in alkaline media. The Ru dopants induced a high content of Ni and Co vacancies in NiCoP nanoparticles, and the more defective Ru doped NiCoP phase than undoped NiCoP ones led to a greater number of catalytically active sites and improved electrical conductivity after undergoing electrochemical activation. The Ru doped NiCoP catalyst exhibited high OER catalytic performance in alkaline media with a low overpotential of 281 mV at 10 mA cm−2 and a Tafel slope of 42.7 mV dec−1. 相似文献