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31.
In this paper, we consider self-mappings defined on a metric space endowed with a finite number of graphs. Under certain conditions imposed on the graphs, we establish a new fixed point theorem for such mappings. The obtained result extends, generalizes and improves many existing contributions in the literature including standard fixed point theorems, fixed point theorems on a metric space endowed with a partial order and fixed point theorems for cyclic mappings. 相似文献
32.
Ciprian Dragan Adrian Samuila Subhankar Das Dan Iancu Mihai Bilici Lucian Dascalescu 《Journal of Electrostatics》2009,67(2-3):184-188
The aim of this study is to refine the understanding of the tribo-electrostatic phenomena that can affect the efficiency of suction-type dilute-phase transport systems. The study was conducted with mm-size ABS-PC particles, a granular material originating from genuine information technology wastes. The tribo-charging process was modelled using the response surface method of experimental design. The controlled variables were the granular material feed rate and the aspirating air speed rate. The monitored variable was the charge imparted to a well-defined section of the duct and which is equal to the charge transferred to the particles passing through that section of the pneumatic transport system. An induction type sensor connected to an electrometer has been employed for the measurements. The data were processed by a virtual instrument developed in LabView. A commercial software package was employed for estimating the effects of the various factors and predicting the optimum operating conditions, which were then confirmed by a final experiment. 相似文献
33.
Mihai Mari 《Journal de Mathématiques Pures et Appliquées》2002,81(12):109-1239
We are interested in the existence of travelling-waves for the nonlinear Schrödinger equation in RN with “ψ3−ψ5”-type nonlinearity. First, we prove an abstract result in critical point theory (a local variant of the classical saddle-point theorem). Using this result, we get the existence of travelling-waves moving with sufficiently small velocity in space dimension N4. 相似文献
34.
M. Petrascu A. Isbasescu I. Lazar I. Mihai H. Petrascu A. T. Rudchik V. A. Chernievski O. A. Ponkratenko V. A. Ziman 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(4):395-399
The energy spectra and angular distributions of products in the reaction27Al(14N,X) have been measured at 116 MeV bombarding energy. It is shown that the energy spectra of the products lighter than the projectile, are well described by a three-body breakup calculation. The experimental total breakup cross-section estimated in the present work, together with Glas-Mosel calculation of the fusion cross-section, are in a reasonable agreement with the optical model total reaction cross-section. 相似文献
35.
Mariana Ciureanu Victor E. Sahini Felicia Cornea Cornelia Cercasov Mihai Contineanu 《Magnetic resonance in chemistry : MRC》1981,15(2):148-151
The barriers to internal rotation about the C? N bond in several thiopiperidides have been determined by the NMR technique. It was found that the barrier height (ΔG?) increases in the series cinnamoylthiopiperidide<thiobenzoylpiperidide<phenylthioacetylpiperidide. This trend was discussed in terms of the electronic structure, using HMO calculations. For m-and p-substituted cinnamoylthiopiperidides the barriers were shown to increase with the electron withdrawing character of the substituent in the aromatic ring. 相似文献
36.
We deal with a Riemannian manifoldM carrying a pair of skew symmetric conformal vector fields (X, Y). The existence of such a pairing is determined by an exterior differential system in involution (in the sense of Cartan).
In this case,M is foliated by 3-dimensional totally geodesic submanifolds. Additional geometric properties are proved.
Supported by a JSPS postdoctoral fellowship. 相似文献
37.
A new route for higher valency ion substitution into the manganese oxide (OMS-2) framework is reported. Isomorphously substituted vanadium and niobium OMS-2 were hydrothermally synthesized at 200 degrees C for a period of 2 days. Characterization by XRD, elemental analysis, Raman spectroscopy, and resistivity studies proved that vanadium was incorporated into the manganese oxide structure. The presence of vanadium in the framework changes the electrical properties, making the material very attractive for water sensing applications. 相似文献
38.
In this paper, te edge mode variation is studied with three different methods: the reciprocal work method, already used by Torvik [J. Acoust. Soc. Am. 41 (1967) 346] to model this phenomenon, the S-parameter method and a finite element model that are applied for the first time to the study of the edge resonance. Moreover, laser probe measurements of the edge mode have also been performed and compared to the numerical predictions. The good agreement between the numerical predictions and the experimental data allows full understanding of the resonant phenomenon. The edge resonance is linked to the strong increase in amplitude of two complex Lamb waves, and the edge mode is proved to radiate into the plate as the first symmetrical Lamb mode S(0). Displacements at the edge and away from the edge have been computed and measured to evaluate the spatial and temporal behaviour of the edge mode. The dependence of the edge resonance frequency and amplitude on the Poisson coefficient has also been studied. 相似文献
39.
We demonstrate the feasibility of optical bistability in an axially modulated nonlinear OmniGuide fiber through analytical theory and detailed numerical experiments. At 1.55-microm carrier wavelength, the in-fiber devices that we propose can operate with only a few tens of milliwatts of power, can have a nearly instantaneous response and recovery time, and can be shorter than 100 microm. 相似文献
40.
In the present paper we want to develop an analytical model to study the thermal behavior of multi-layered solid media in interaction with a laser beam. We suppose that each layer has a constant thermal conductivity. We consider that the laser beam is formed by decoupled [Phys Rev A 1996; 53: 4435] multi-modes Hermite–Gauss beams. The model is applied using the classical heat equation which was solved using the integral transform method [Infrared Phys Technol 2002; 42: 31; Optics Laser Technol 2004; 36: 219–22; Optics Laser Technol 2004; 36: 677–9; Proc SPIE 2003; 5227: 323]. 相似文献