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171.
V. I. Kusov A. K. Gruznov V. I. Kulichkov N. P. Kusova A. V. Dyubchenko 《Metallurgist》1989,33(11):224-225
Institute of Ferrous Metallurgy. Novolipetsk Metallurgical Combine. Translated from Metallurg, No. 11, pp. 32–33, November, 1989. 相似文献
172.
173.
174.
Hayashi M. Tanaka H. Ohara K. Otani T. Suzuki M. 《Lightwave Technology, Journal of》2002,20(2):236-242
An all-optical multiplexing technique using wavelength division multiplexing (WDM)-time division multiplexing (TDM) conversion with an electroabsorption wavelength converter has been proposed and demonstrated. The effectiveness of this WDM-TDM conversion technique for various pulsewidth settings was experimentally investigated. The fluctuation of the signal performance, which was inevitably caused by the coherent crosstalk between adjacent pulses in the conventional optical time division multiplexing (OTDM) technique, were successfully suppressed, even in the case of wide pulse duration. High Q-factor performance has been maintained for a wide range of duty ration from 36% to 74%. By introducing this technique to the optical time division multiplexer, a highly stable and high-quality 40-Gb/s optical signal can be effectively produced without generating the short pulse or setting two tributaries at orthogonal polarization states, and without introducing high-speed electronics for signal multiplexing. The WDM-TDM conversion with an electroabsorption wavelength converter was extended to 60-Gb/s operation by using three 20-Gb/s tributaries. A clear eye opening was confirmed for a waveform after the WDM-TDM conversion of the 60-Gb/s signal 相似文献
175.
M. Liess R. Hua K. Elsenaar 《The International Journal of Advanced Manufacturing Technology》2002,20(1):58-62
Cables to moving parts on a linear actuator in production machines, such as pick-and-place machines, are a source of unreliability
owing to the possible breaking of a cable. They further reduce the positioning precision of the actuator owing to additional
forces. Slotted waveguide systems for rail vehicles based on 2.4 GHz transmission frequency are well known, but transmitters/receivers
and waveguides are bulky. The paper reports on the reduction in size of the equipment, adapted to 5.8 GHz using a commercial
off-the-shelf RadioLan communication module. Further, the efficient termination of the wave-guide and a new way to reduce
standing-wave effects is also discussed. 相似文献
176.
J. Suutarinen K. Honkapää R.-L. Heiniö A. Mustranta H. Liukkonen-Lilja M. Mokkila 《Journal of food science》2002,67(3):1240-1248
ABSTRACT: :
Different calcium chloride (CaCl2 ) and pectin methylesterase (PME) prefreezing treatments in a vacuum were used to clarify the most effective prefreezing factors for strawberries and traditional jams. Fractional factorial design and modeling were used. CaCl2 had the greatest effect on the majority of the 15 studied responses ( p < 0.001). The pretreatment time should be short (about 5 to 10 min), the temperature low (less than 20 °C), the vacuum level high (pressure less than 10 kPa), the CaCl2 concentration moderate (about 1%) and the dosage of PME comparatively low (about 50 to 100 nkat/g) in order to yield high quality frozen strawberries for jam making. 相似文献
Different calcium chloride (CaCl
177.
K. A. Abdikalikov V. K. Zadiraka O. S. Kondratenko S. S. Mel'nikova 《Cybernetics and Systems Analysis》1991,27(3):414-419
A fast algorithm is proposed for estimating the auto- and cross-correlation functions of a large signal. The algorithm is based on the sectioning method by the fast Fourier transform. We determine the optimal length of the portion of data read from external memory into RAM which achieves Tmin—a minimum processing time. An estimate of Tmin is obtained.Translated from Kibernetika, No. 3, pp. 78–81, May–June, 1991. 相似文献
178.
179.
Statistics on the backscatter coefficient σ0 from the Ku -band Seasat-A Satellite Scatterometer (SASS) collected over the world's land surfaces are presented. This spaceborne scatterometer provided data on σ0 between latitude 80° S and 80° N at incidence angles up to 70°. The global statistics of vertical (V ) and horizontal (H ) polarization backscatter coefficients for 10° bands in latitude are presented for incidence angles between 20° and 70° and compared with the Skylab and ground spectrometer results. Global images of the time-averaged V polarization σ0 at a 45° incidence angle and its dependence on the incidence angle are presented and compared to a generalized map of the terrain type. Global images of the differences between the V an H polarization backscatter coefficients are presented and discussed. The most inhomogeneous region, which contains the deserts of North Africa and the Arabian Peninsula, is studied in greater detail and compared with the terrain type 相似文献
180.
Shamansky H.T. Dominek A.K. Peters L. Jr. 《Antennas and Propagation, IEEE Transactions on》1989,37(8):1019-1025
The traveling-wave energy, which multiply diffracts on a straight thin wire, is represented as a sum of terms, each with a distinct physical meaning, that can be individually examined in the time domain. Expressions for each scattering mechanism on a straight thin wire are cast in the form of four basic electromagnetic wave concepts: diffraction, attachment, launch, and reflection. Using the basic mechanisms from P.Ya. Ufimtsev (1962), each of the scattering mechanisms is included into the total scattered field for the straight thin wire. Scattering as a function of angle and frequency is then compared to the moment-method solution. These analytic expressions are then extended to a lossy wire with a simple approximate modification using the propagation velocity on the wire as derived from the Sommerfeld wave on a straight lossy wire. Both the perfectly conducting and lossy wire solutions are compared to moment-method results, and excellent agreement is found. As is common with asymptotic solutions, when the electrical length of wire is smaller than 0.2 λ the results lose accuracy. The expressions modified to approximate the scattering for the lossy thin wire yield excellent agreement even for lossy wires where the wire radius is on the order of skin depth 相似文献