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51.
The paper studies the motion laws influence over the VIPAS1 industrial robot working. The motion differential equations, that govern the motion robot were established. Using them we can study the direct problem for the robot dynamics. There are the given motion laws for the accelerated and decreasing motion having triangular, trapezoidal and parabolic forms. The graphics of the forces and moments give us the possibility to make some recommandations under energetic aspects, for the optimal solutions about the VIPAS1 industrial robot. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
52.
Viorel Cîrcu Mihaela Ilie Monica Iliş Florea Dumitraşcu Ionela Neagoe Simona Păsculescu 《Polyhedron》2009,28(17):3739-3746
A series of cyclometallated 2-phenylpyridine Pt(II) complexes having N-benzoyl thiourea derivatives as ancillary ligands were prepared and characterised by elemental analysis, IR and UV–Vis spectroscopy, 1H and 13C NMR spectroscopy as well as by X-ray diffraction on single-crystal. All complexes were obtained as a single isomer with N atom of the 2-phenylpyridine ligand and S atom of the N-benzoyl thiourea derivatives coordinated in trans positions to the platinum metal as evidenced by using X-ray crystallography and NMR spectroscopy. All Pt(II) complexes show good luminescence properties at room temperature, both in dichloromethane solution and in solid state. 相似文献
53.
Viorel P. Paun 《Central European Journal of Physics》2009,7(2):264-269
The SEM microfractographies of Zircaloy-4 are studied by the time-series method. We first develop a computer application which
associates a time series to each SEM micrograph. Furthermore, we will apply the phase space embedding technique to reconstruct
the attractor and to compute the autocorrelation dimension. Using the fractal analysis technique, the SEM microfractographies
of the fracture surface of the Zircaloy-4 samples have been analyzed.
相似文献
54.
55.
Viorel Barbu Irena Lasiecka Mohammad A. Rammaha 《Transactions of the American Mathematical Society》2005,357(7):2571-2611
In this article we focus on the global well-posedness of the differential equation , where is a sub-differential of a continuous convex function . Under some conditions on and the parameters in the equations, we obtain several results on the existence of global solutions, uniqueness, nonexistence and propagation of regularity. Under nominal assumptions on the parameters we establish the existence of global generalized solutions. With further restrictions on the parameters we prove the existence and uniqueness of a global weak solution. In addition, we obtain a result on the nonexistence of global weak solutions to the equation whenever the exponent is greater than the critical value , and the initial energy is negative. We also address the issue of propagation of regularity. Specifically, under some restriction on the parameters, we prove that solutions that correspond to any regular initial data such that , are indeed strong solutions.
56.
Let
be the restriction to a hyperbolic basic set of a smooth diffeomorphism. We find several criteria for transitivity of noncompact connected Lie group extensions. As a consequence, we find transitive extensions for any finite-dimensional connected Lie group extension. If, in addition, the group is perfect and has an open set of elements that generate a compact subgroup, we find open sets of stably transitive extensions. In particular, we find stably transitive
-extensions. More generally, we find stably transitive
-extensions for all n ≥ 1. For the Euclidean groups SE(n) with n ≥ 4 even, we obtain a new proof of a result of Melbourne and Nicol stating that there is an open and dense set of extensions that are transitive.For groups of the form
where K is compact, a separation condition is necessary for transitivity. Provided X is a hyperbolic attractor, we show that an open and dense set of extensions satisfying the separation condition are transitive. This generalizes a result of Niţică and Pollicott for
-extensions.Communicated by Viviane Baladisubmitted 24/05/04, accepted 11/10/04 相似文献
57.
Viorel?BadescuEmail author Peter T.?LandsbergEmail author 《Foundations of Physics Letters》2005,18(3):205-226
Ideal Bose and Fermi systems are studied on the basis of a canonical ensemble, subject to the condition that their temperature is less than a given temperature Tmax. A single new parameter (the tau-parameter, τ) is needed to keep account of the new constraint. The parameter τ is shown to be the exponential of a pseudo-chemical potential that is linearly dependent on temperature. The inclusion of the τ- parameter leads to generalizations of usual thermodynamic quantities (internal energy, heat capacity and entropy) and various particular cases are discussed. The heat capacity of a Bose system can exhibit a maximum at a temperature less than the maximum temperature Tmax. The number of micro-states in the canonical ensemble is found to increase with τ. The heat capacity cV of a Fermi system of non-interacting spins exhibits a Schottky anomaly. The peak depends on τ, and for some cases cV/k can significantly exceed unity. The influence of τ on the entropy of the Fermi system and on the number of micro-states in the canonical ensemble is significant but not spectacular. 相似文献
58.
59.
Gini G Craciun MV König C Benfenati E 《Journal of chemical information and computer sciences》2004,44(6):1897-1902
Most quantitative structure-activity relationship (QSAR) models are linear relationships and significant for only a limited domain of compounds. Here we propose a data-driven approach with a flexible combination of unsupervised and supervised neural networks able to predict the toxicity of a large set of different chemicals while still respecting the QSAR postulates. Since QSAR is applicable only to similar compounds, which have similar biological and physicochemical properties, large numbers of compounds are clustered before building local models, and local models are ensembled to obtain the final result. The approach has been used to develop models to predict the fish toxicity of Pimephales promelas and Tetrahymena pyriformis, a protozoan. 相似文献
60.
S. L. Neave G. G. Longinescu Margareta N. Badescu und Th. I. Pirtea 《Fresenius' Journal of Analytical Chemistry》1931,86(5-6):255-257
Ohne Zusammenfassung 相似文献