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31.
This paper investigates switching of one beam by another in a Kerr type nonlinear Mach–Zehnder interferometer (NMZI) with two input ports and one output port. The present investigation has been carried out using the beam propagation method (BPM). The paper presents a detailed account on the procedures used to choose the parameters of the NMZI to make it behave like a NOT gate (inverter), an AND gate, an amplifier and a wavelength converter. The paper also gives details on the manipulation of the operating inputs of the NMZI to desired values. It is shown that the operating values of both the inputs of the NMZI can simultaneously be increased/decreased by decreasing/increasing the nonlinearity coefficient of nonlinear arm of the NMZI. Variation of NMZI length varies the operating value of only the first input, keeping the second unchanged, while variation of NMZI offset varies the operating value of only the second, keeping the first unchanged. The paper also gives a detailed account on amplification of the NMZI amplifier/wavelength converter. The present investigation is useful from the scientific as well as engineering point of view. 相似文献
32.
33.
The object of the present paper is to investigate the radial motion of a solid spherical body, assumed to be homogeneous, isotropic and elastic, in presence of a magnetic field in the azimuthal direction. The body is assumed to be in a state of initial stress which is hydrostatic in nature. This theory of radial motion of a solid spherical body in a magnetic field has been utilised to find the small radial motion of a solid Earth assumed to be homogeneous isotropic elastic sphere in presence of a magnetic field in the azimuthal direction. Considering the effect of gravity and the initial stress produced by slow process of creep due to extra masses over the surface of the Earth, the fundamental equations of motion are derived which are non-linear in character and are solved. The times of a desired radial displacement are calculated in presence of a magnetic field only and in presence of the same magnetic field, initial stress and gravitational field, which are compared and exhibited numerically. 相似文献
34.
V. Malíšek 《Czechoslovak Journal of Physics》1965,15(12):929-932
An attempt is made to derive general expressions for temperature factors to which the intensities of the absorption bands of the vibrational spectrum of molecules are directly proportional. For the sake of simplicity, the process of induced emission is neglected. The temperature factor for the line corresponding to the transition (v
1,v
2,...,v
s
) (v
1+p
1,v
2+P
2,...,v
s
+p
s
) with multiplicity 1,2, ..., is given by expression (3) and the temperature factor for the band is given by expression (4). These relations were used to calculate the ratios of the temperature factors for the case of double and triple degenerate energy levels and satisfactory agreement with the experimental results studied in paper [2] was obtained.
Abschließend möchte ich Herrn Ing. A. Vako für die Veranlassung zu dieser Arbeit bestens danken. 相似文献
Abschließend möchte ich Herrn Ing. A. Vako für die Veranlassung zu dieser Arbeit bestens danken. 相似文献
35.
36.
We analyze noise immunity of high-speed data transmission systems operated in a complex communication channel with frequency-selective
fadings and interference from the neighboring base stations. This problem is very topical for modern orthogonal frequency-division
multiple-access (OFDMA) data transmission standards. Such digital communication systems allow one to measure the noise parameters
on individual subcarriers simultaneously with reception useful signals. We perform comparative analysis of different methods
for measuring the noise characteristics and using them for demodulating the coded signal. Four processing methods with different
complexity and noise immunity degree are proposed for receiver signals. Characteristics of the considered receivers are compared
for different channel loadings and algorithms of power control by interfering stations. Practical recommendations for using
the considered receivers are given.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 50, No. 6, pp. 533–543, June 2007. 相似文献
37.
D. V. Belykh M. V. Mal’shakova M. G. Korochkina V. E. Kataev A. V. Kuchin 《Chemistry of Natural Compounds》2011,47(4):612-614
Acylation by suberic acid chloride of chlorin with two oximated isosteviol groups on its periphery produced for the first
time a macrocyclic system containing a porphyrin ring and two tetracyclic ent-beyerane frameworks. 相似文献
38.
39.
V. S. Mal’kov D. A. Kokova A. S. Knyazev T. I. Izaak D. V. Nepomnyashchikh L. N. Kurina 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2011,85(4):690-694
A procedure for the purification of aqueous glyoxal (obtained by the partial oxidation of glycol) from carboxylic acids was
described. Mono- and dibasic organic acids can be removed from solution without any substantial losses of glyoxal by using
weakly basic EDE-10P and AN-31 anionites. A mechanism of the adsorption of carboxylic acids on weak resins was suggested based
on the IR spectra recorded in a study of AN-31 anion-exchange resin. Using this method of purification also allowed the removal
of the glyoxal condensation products from solution. 相似文献
40.