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41.
Virgiliu Craciun Ghiorghe Calugaru Vasile Badescu 《Czechoslovak Journal of Physics》2002,52(5):725-728
We have created a fast algorithm for calculating the temperature profile in a living tissue treated by magnetic fluid hyperthermia.
Our algorithm solves an equation by the finite difference method. This equation includes the “heat sink” and “K-effective”
effects. The algorithm need not an initial solution and it has the peculiarity that it makes a recursive division of the network,
reducing thus the calculation period 5–9 times. 相似文献
42.
Vasile Brînzânescu 《manuscripta mathematica》1993,79(1):187-195
Research supported by Alexander von Humboldt-Stiftung 相似文献
43.
Holomorphic vector bundles on primary Kodaira surfaces 总被引:2,自引:0,他引:2
44.
Dr. Vasile I. Istrătescu 《Mathematische Zeitschrift》1972,124(3):199-202
45.
Vasile Dragan Aristide Halanay Vlad Ionescu 《Integral Equations and Operator Theory》1994,19(2):153-215
It is proved that for the discrete-time linear systems with time-varying coefficients the existence of a controller which simultaneously stabilizes and provides prescribed disturbance attenuation for the resultant closed-loop system, implies the existence of global solutions to several Kalman-Szegö-Popov-Yakubovich systems. It is also proved that this fact is equivalent to the existence of the positive semidefinite stabilizing solutions to corresponding game-theoretic Riccati equations. The family of all controllers with the above mentioned properties is constructed in terms of the solutions to the cited Kalman-Szegö-Popov-Yakubovich systems. The main tool is the generalized Popov-Yakubovich theory which is essentially developed in an operator-theoretic framework. 相似文献
46.
In this paper we present some new and pertinent connections between the Strong Optimization and the Approximate Pareto type
Efficiency, in particular, with the usual Vector Optimization, at first in the Ordered Vector Spaces by the natural Convex
Cones and, afterwards, in the Ordered Hausdorff Locally Convex Spaces. The main result is obtained considering the notion
of full nuclear cone. Our results, is related to an appropriate scalarization method
Mathematics Subject Classification (2000). 90C29 相似文献
47.
This paper reports the mass spectrum of vinyltrimethylsilane over the range of electron-impact energy of 9 to 70 eV as determined with a quadrupole mass spectrometer. Less extensive data obtained with magnetic spectrometers are included for comparison as well as the spectrum of vinyl-tri(methyl-d3)silane. Plots of ion intensity as a function of electron energy, nominal appearance potentials and metastable ion transitions are given. The primary ionization results in an electron deficiency on the silicon atom, followed by loss of either ·CH3, C2H4 or ·C2H3 to give fragments of mass 85, 73 or 72, respectively. The primary fragment of mass 85 loses C2H2 to give the mass 59 ion. The primary fragment of mass 73 loses successively C2H4 and H2 to give first the mass 45 ion and then the mass 43 ion. At 15 eV, the relative intensities of the ions are 85 > 72 > 100 > 59 > 73. At 70 eV, the relative intensities are 59 > 85 > 43 > 45 > 73 > 72 > 100. 相似文献
48.
Nicolae Leopold Simona CîntÎ‐Pînzaru Lszl Szab Daniela Ilean Vasile Chi Onuc Cozar Wolfgang Kiefer 《Journal of Raman spectroscopy : JRS》2010,41(3):248-255
Conjugate acid–base forms of the drug metoclopramide were investigated by Raman spectroscopy in aqueous solutions and by surface‐enhanced Raman scattering (SERS), when the molecules were adsorbed on colloidal silver surfaces. Raman spectra were recorded at pH values below 8, metoclopramide being poorly water soluble at higher pH values. The SERS spectra of metoclopramide were recorded in the 3–11 pH range, even in spite of its low solubility at basic pH values. The Raman and SERS spectra were assigned by means of density functional theory (DFT) calculations. By monitoring several SERS marker bands, the protonated, neutral or the coexistence of both molecular species adsorbed on the colloidal silver particles could be evidenced. The adsorbate orientation was deduced to be perpendicular to the metal surface for the protonated molecular species and tilted for the neutral metoclopramide molecular species. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
49.
Vasile Mioc Daniel Paşca Cristina Stoica 《Nonlinear Analysis: Real World Applications》2010,11(2):920-931
The motion of a material point of unit mass in a field determined by a generalized Hénon–Heiles potential , with standard Cartesian coordinates and , is addressed for two limit situations: collision and escape. Using McGehee-type transformations, the corresponding collision and infinity boundary manifolds pasted on the phase space are determined. These are fictitious manifolds, but, due to the continuity with respect to initial data, their flow determines the near by orbit behaviour.The dynamics on the collision and infinity manifolds is fully described. The topology of the flow on the collision manifold is independent of the parameters. In the full phase space, while spiraling collision orbits are present, most of the orbits avoid collision. The topology of the flow on the infinity manifold changes as the ratio between and varies. More precisely, there are two symmetric pitchfork bifurcations along the line , due to the reshaping of the potential along the bifurcation line. Besides rectilinear and spiraling orbits, the near-escape dynamics includes oscillatory orbits, for which angular momentum alternates sign. 相似文献
50.
Manuela Iftime Carmen Racles Vasile Cozan Maria Bruma Alexander L'Vovich Rusanov 《Journal of Macromolecular Science: Physics》2013,52(8):1668-1680
Three poly(arylene ether sulfone)s (two polymers and one copolymer) containing diphenylfluorene, phenolphthalein and 2,4-bis[(4-chlorophenyl)sulfonyl]-1-(phenyltio) benzene)] units were synthesized by the classical Williamson polyetherification reaction. The association phenomenon in N,N-dimethylformamide (DMF) was investigated by different methods: gel permeation chromatography (GPC), viscosity, atomic force microscopy (AFM), fluorescence spectroscopy and dynamic light scattering (DLS). Both AFM and DLS measurements evidenced the formation of aggregates with spherical or ellipsoidal shape at a concentration around 0.05 wt.%. This behavior could be explained by dipole-dipole interactions between macromolecular chains, probably with the participation of solvent molecules, and by H-bonds involving hydroxyl end groups. 相似文献