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61.
In the present work we show that the local generalized monotonicity of a lower semicontinuous set-valued operator on some certain type of dense sets ensures the global generalized monotonicity of that operator. We achieve this goal gradually by showing at first that the lower semicontinuous set-valued functions of one real variable, which are locally generalized monotone on a dense subsets of their domain are globally generalized monotone. Then, these results are extended to the case of set-valued operators on arbitrary Banach spaces. We close this work with a section on the global generalized convexity of a real valued function, which is obtained out of its local counterpart on some dense sets.  相似文献   
62.
We investigate a general control problem for a class of nonlinear parabolic evolution equations. Applications are related to solid-solid and solid-liquid phase transitions.

We prove compactness of the solution operators, existence of optimal controls and show convergence of the finite-dimensional approximate control problem to the original one.  相似文献   
63.
We give a formula for the one-parameter strongly continuous semigroups ${e^{-tL^{\lambda}}}We give a formula for the one-parameter strongly continuous semigroups e-tLl{e^{-tL^{\lambda}}} and e-t [(A)\tilde]{e^{-t \tilde{A}}}, t > 0 generated by the generalized Hermite operator Ll, l ? R\{0}{L^{\lambda}, \lambda \in {\bf R}\backslash \{0\}} respectively by the generalized Landau operator ?. These formula are derived by means of pseudo-differential operators of the Weyl type, i.e. Weyl transforms, Fourier-Wigner transforms and Wigner transforms of some orthonormal basis for L 2(R 2n ) which consist of the eigenfunctions of the generalized Hermite operator and of the generalized Landau operator. Applications to an L 2 estimate for the solutions of initial value problems for the heat equations governed by L λ respectively ?, in terms of L p norm, 1 ≤ p ≤ ∞ of the initial data are given.  相似文献   
64.
Reactions of [MCl2(L-L)], M = Pt, Pd; L-L = bis(diphenylphosphino)methane (dppm) or bis(diphenylphosphino)ethane (dppe), with NaC5H4SN in a 1 : 2 molar ratio lead to mononuclear species [M(S-C5H4SN)2(P-P)], M = Pt; L-L = dppm (1) or dppe (2) and M = Pd; L-L = dppe (3), as well as to the dinuclear [Pd2(micro2-S,N-C5H4SN)(micro2-kappa2S-C5H4SN)(micro2-dppm)(S-C5H4SN)2] (4). In contrast, reaction of [MCl2(dppm)] with NaC5H4SN in a 1 : 1 molar ratio leads to [Pd2(micro2-S,N-C5H4SN)3(micro2-dppm)]Cl (5) and trans-[Pt(S-C5H4SN)2(PPh2Me)2] (6) respectively. The latter is formed in low yield by cleavage of the dppm ligand. The dinuclear derivatives 4 and 5 present an A-frame and lantern structure, respectively. The former showing three different co-ordination modes in the same molecule with a short Pd-Pd distance of 2.9583 (9) A and the latter with three bridging S,N thionate ligands showing a shorter Pd-Pd distance of 2.7291 (13) A. Both distances could be imposed by the bridging ligands or point to some sort of metal-metal interaction.  相似文献   
65.
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   
66.
We generalize the so-called wavelet transform modulus maxima (WTMM) method to multifractal image analysis. We show that the implementation of this method provides very efficient numerical techniques to characterize statistically the roughness fluctuations of fractal surfaces. We emphasize the wide range of potential applications of this wavelet-based image processing method in fundamental as well as applied sciences. This paper is the first one of a series of three articles. It is mainly devoted to the methodology and to test applications on random self-affine surfaces (e.g., isotropic fractional Brownian surfaces and anisotropic monofractal rough surfaces). Besides its ability to characterize point-wise regularity, the WTMM method is definitely a multiscale edge detection method which can be equally used for pattern recognition, detection of contours and image denoising. Paper II (N. Decoster, S.G. Roux, A. Arnéodo, to be published in Eur. Phys. J. B 15 (2000)) will be devoted to some applications of the WTMM method to synthetic multifractal rough surfaces. In paper III (S.G. Roux, A. Arnéodo, N. Decoster, to be published in Eur. Phys. J. 15 (2000)), we will report the results of a comparative experimental analysis of high-resolution satellite images of cloudy scenes. Received 8 July 1999  相似文献   
67.
New measurements of the (N(CH3 )4 )2 MnBr4 specific heat by adiabatic calorimetry around the ferro- paraelastic phase transition shown by the crystal around 276 K are compared with previous calorimetric studies on similar tetramethylammonium bromide compounds. The thermodynamic behaviour of the tribromides and tetrabromides derivatives together with the influence on the phase transition parameters of the cation and halogen molecular substitutions are examined. The thermal relaxation experiments permit to study the behaviour of the crystals thermal conduction as a function of the temperature. Finally, the Landau theory for second order phase transitions is used to describe the thermodynamic behaviour of some of these crystals. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
68.
69.
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   
70.
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   
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