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201.
In this paper we show that delay embedding produces spurious structures in a recurrence plot (RP) that are not present in
the real attractor. We analyze typical sets of simulated data, such as white noise and data from the chaotic R?ssler system
to show the relevance of this effect.
In the second part of the paper we show that the second order Rényi entropy and the correlation dimension are dynamical invariants
that can be estimated from Recurrence Plots with arbitrary embedding dimension and delay. 相似文献
202.
Alberto Calabri Ciro Ciliberto Flaminio Flamini Rick Miranda 《Rendiconti del Circolo Matematico di Palermo》2008,57(1):1-31
Abstract In this paper we study smooth, non-special scrolls S of degree d, genus g ≥ 0, with general moduli. In particular, we study the scheme of unisecant curves of a given degree on S. Our approach is mostly based on degeneration techniques.
Keywords Ruled surfaces, Hilbert schemes of scrolls, Moduli, Embedded degenerations
Mathematics Subject Classification (2000) 14J26, 14D06, 14C20, (Secondary) 14H60, 14N10 相似文献
203.
The immersion in HF solutions of silicon containing nanocavities (produced by the annealing at high temperature, 950 °C, of silicon implanted with helium at high fluence, 2 × 1016 cm−2) results in the injection of hydrogen in an infrared-mute state (most likely H2) into the nanocavities. The pressure achieved in the cavities is sufficiently high to stabilize the hydrogen coverage of the inner surfaces at temperatures exceeding by 200 °C the one of complete desorption from the outer surface. 相似文献
204.
205.
Femtosecond ablation of ultrahard materials 总被引:4,自引:0,他引:4
G. Dumitru V. Romano H.P. Weber M. Sentis W. Marine 《Applied Physics A: Materials Science & Processing》2002,74(6):729-739
Several ultrahard materials and coatings of definite interest for tribological applications were tested with respect to their
response when irradiated with fs laser pulses. Results on cemented tungsten carbide and on titanium carbonitride are reported
for the first time and compared with outcomes of investigations on diamond and titanium nitride. The experiments were carried
out in air, in a regime of 5–8 J/cm2 fluences, using the beam of a commercial Ti:sapphire laser. The changes induced in the surface morphology were analysed with
a Nomarski optical microscope, and with SEM and AFM techniques. From the experimental data and from the calculated incident
energy density distributions, the damage and ablation threshold values were determined. As expected, the diamond showed the
highest threshold, while the cemented tungsten carbide exhibited typical values for metallic surfaces. The ablation rates
determined (under the above-mentioned experimental conditions) were in the range 0.1–0.2 μm per pulse for all the materials
investigated.
Received: 31 August 2001 / Accepted: 3 December 2001 / Published online: 20 March 2002 相似文献
206.
T. Spillane F. Raiola F. Zeng H. W. Becker L. Gialanella K. U. Kettner R. Kunze C. Rolfs M. Romano D. Schürmann F. Strieder 《The European Physical Journal A - Hadrons and Nuclei》2007,31(2):203-205
For the β--decay of 198Au in a Au metallic environment the half-life was observed to be longer by 0.4±0.7% at room temperature (T = 293K) and by 4.0±0.7% when the metal was cooled to T = 12K, both compared to the literature value of T
1/2 = 2.6943±0.0008d. 相似文献
207.
Caramella P Quadrelli P Toma L Romano S Khuong KS Northrop B Houk KN 《The Journal of organic chemistry》2005,70(8):2994-3008
The three potential energy surfaces of the trans-trans, cis-trans, and cis-cis divinyltetramethylene diradicals have been located with DFT calculations at the BPW91/6-311+G levels. The three surfaces account well for the experimental results reported for the thermolysis of optically active trans-1,2-divinylcyclobutane and optically active and deuterated 4-vinylcyclohexene. The surfaces account also for the outcome of the dimerization of butadiene and the thermolysis of cis,cis-1,5-cyclooctadiene. The three diradical intermediates are connected to the cyclization and dissociation products through conformations that are explored fully here. 相似文献
208.
T.V. Kononenko S.M. Pimenov V.V. Kononenko E.V. Zavedeev V.I. Konov G. Dumitru V. Romano 《Applied Physics A: Materials Science & Processing》2004,79(3):543-549
Laser-induced multilevel spallation in diamond-like carbon films is observed and studied for a wide range of laser parameters (=539, 800, 1064, and 1078 nm; =100 fs, 300 ps, 10 ns, and 150 ns; E>0.1 J/cm2). Laser irradiation causes the detachment and removal of material layers, whose lateral size is comparable with the irradiated area and whose thickness of 10–200 nm is much less than the DLC film thickness. The influence of the laser parameters on the thickness, size, and number of removed layers is examined. A qualitative explanation of laser-induced spallation in DLC films is proposed, which is based on the fact that the absorbed laser pulse produces a rapidly expanding surface layer of modified structure and reduced density. PACS 42.62.Cf; 61.80.Ba; 81.40.Wx 相似文献
209.
210.
R. Russo M. Malinconico L. Petti G. Romano 《Journal of Polymer Science.Polymer Physics》2005,43(10):1205-1213
Films of biodegradable blends based on sodium alginate for applications in agriculture, as films for the solarization of soils, were prepared and characterized in terms of the mechanical parameters and optical properties. The films analyzed in this study were transparent in the visible region and opaque in the infrared region. This ensured a micro greenhouse effect on the soil. One of the films was also characterized optically in the ultraviolet–visible–infrared region. The optical data were analyzed with a theoretical model, which was able to predict the temperature of the soil at different depths and at different times of the day. The susceptibility time of the film was compatible with its use in agriculture as a film for solarization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1205–1213, 2005 相似文献