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71.
Leonid G. Kazovsky Eli Turgeman 《International Journal of Circuit Theory and Applications》1982,10(3):231-242
A non-recursive adaptive impulse noise canceller (AINC) is investigated. The AINC is designed to suppress long impulsive interferences which are a primary source of errors in many communication systems. Performance of the AINC depends upon the input filter of the receiver. It is shown that the optimum input filter is LPF; the optimum LPF bandwidth exists which provides the minimum error rate of the receiver. The system error rate is studied by means of a computer simulation. Simulation results indicate that the AINC provides a very effective suppression of impulse noise. However, conditions in a real communication channel may be quite different from those chosen for simulation. Therefore, further research remains to be done before the AINC can be recommended for practical applications. 相似文献
72.
73.
Olga P. Tkachenko Alexander Yu. Stakheev Leonid M. Kustov Igor V. Mashkovsky Maurits van den Berg Wolfgang Grünert Natalya Yu. Kozitsyna Zhanna V. Dobrokhotova Valery I. Zhilov Sergei E. Nefedov Michael N. Vargaftik Ilya I. Moiseev 《Catalysis Letters》2006,112(3-4):155-161
The heterobimetallic lantern complex Pd(μ-OOCMe)4Zn(OH2) was found to be readily reduced with H2 under fairly mild conditions (150–250 °C, 5–10% H2/He) both in the carbon-supported and crystalline states to afford a Pd–Zn nanoalloy as evidenced by the ICP elemental analysis,
EXAFS, XANES and XRD data.
相似文献
74.
Pedro X. La Hera Leonid B. Freidovich Anton S. Shiriaev Uwe Mettin 《Mechatronics》2009,19(8):1240-1250
The problem of swinging up inverted pendulums has often been solved by stabilizing a particular class of homoclinic structures present in the dynamics of a physical pendulum. Here, new arguments are suggested to show how other homoclinic curves can be preplanned for dynamics of the passive-link of the robot. This is done by reparameterizing the motions according to geometrical relations among the generalized coordinates, which are known as virtual holonomic constraints. After that, conditions that guarantee the existence of periodic solutions surrounding the planned homoclinic orbits are derived. The corresponding trajectories, in contrast to homoclinic curves, admit efficient design of feedback control laws ensuring exponential orbital stabilization. The method is illustrated by simulations and supported by experimental studies on the Furuta pendulum. The implementation issues are discussed in detail. 相似文献
75.
刘庆备 《高科技纤维与应用》2009,34(3):31-36
通过调节高分子体系的结构,可以有目的性地设计含有固化药物成分(如生物酶和/或抗菌剂)的高分子基体结构,生物活性的高低主要由固化的药物成分决定。 相似文献
76.
Valentina Matveeva Alexey Bykov Valentin Doluda Mikhail Sulman Narendra Kumar Stanislaw Dzwigaj Eric Marceau Leonid Kustov Olga Tkachenko Esther Sulman 《Topics in Catalysis》2009,52(4):387-393
In the present work, nanocatalysts prepared on inorganic supports (zeolites) were investigated in d-glucose oxidation and compared to systems supported on polymer (hypercrosslinked polystyrene (HPS)) previously described.
Catalytic activities and selectivities were measured under various reaction conditions. The selectivity of d-glucose oxidation and activity of both Pd-containing zeolites and HPS-Ru were similar (99.7% and TOF 0.013–0.014 mol/(mol Me s)).
Physicochemical analysis X-ray photoelectron spectroscopy, liquid nitrogen physisorption, diffuse reflectance infrared Fourier
transform spectroscopy of adsorbed CO for metal sites evaluation, CD3CN for acid sites evaluation showed that Pd species were in oxidic form, while Ru species were in oxidic and reduced form.
The catalytic activity decreased when acidic sites were present in Pd-containing zeolites. 相似文献
77.
Leonid Belostotski James W. Haslett 《Analog Integrated Circuits and Signal Processing》2008,55(2):125-137
This paper presents a noise figure optimization technique for source-degenerated cascode CMOS LNAs with lossy gate inductors. The optimization technique, based on two-port theory, takes into account second order parasitic components. The effect of inductive source degeneration on LNA noise parameters is discussed. Measured noise figures agree well with the simulations confirming the accuracy of the noise model and allowing us to investigate the contributions of various components to the overall noise figure. A 0.18-μm CMOS LNA with an integrated inductor (Q = 7.5) achieves a noise figure of 1.16 dB and a return loss of 20 dB at 1.4 GHz, drawing 39 mA from a 1.8-V voltage supply, having gain (S 21) of 14.5 dB, input P1dB of ?17.5 dBm, and input IP3 of ?13 dBm. LNAs with external inductors having quality factor of Q = 170 and Q = 40 achieve noise figures of 0.65 dB and 0.68 dB and a return loss of 20 dB at 1.4 GHz, drawing 37 mA from a 1.8-V voltage supply, having gain (S 21) of 17 dB, input P1dB of ?22 dBm, and input IP3 of ?14 dBm. The large power consumption of the presented designs was intentionally selected in order to reduce the noise figure, an acceptable trade-off for LNA’s targeted for radio telescope applications, and to assess the impact of the large currents flowing through interconnect metals on the noise figure 相似文献
78.
Professor Utkin proposed an example showing that the amplitude of chattering caused by the presence of parasitic dynamics (stable actuators) in some systems governed by the First‐Order Sliding‐Mode Controller is lower than that produced by the Super‐Twisting Algorithm. This example served to motivate this paper reconsidering the problem of comparison of chattering in systems with stable actuators, and driven by Discontinuous Sliding‐Mode Controllers (DSMCs) and Continuous Sliding‐Mode Controllers (CSMCs). Comparison of chattering produced by DSMC and CSMC taking into account their amplitudes, frequencies, and average power (AP) needed to maintain the system into real‐sliding modes, allowing to conclude the following: (i) for systems with slow actuators, the amplitude of oscillations and AP produced by DSMC be smaller than those caused by CSMC; (ii) for bounded disturbances with fixed Lipschitz constant, there exist sufficiently fast actuators for which the amplitude of oscillations and AP produced by CSMC be smaller than those caused by DSMC. 相似文献
79.
Alexander S. Goryashchenko Maria G. Khrenova Anna A. Bochkova Tatiana V. Ivashina Leonid M. Vinokurov Alexander P. Savitsky 《International journal of molecular sciences》2015,16(7):16642-16654
This article describes the genetically encoded caspase-3 FRET-sensor based on the terbium-binding peptide, cleavable linker with caspase-3 recognition site, and red fluorescent protein TagRFP. The engineered construction performs two induction-resonance energy transfer processes: from tryptophan of the terbium-binding peptide to Tb3+ and from sensitized Tb3+ to acceptor—the chromophore of TagRFP. Long-lived terbium-sensitized emission (microseconds), pulse excitation source, and time-resolved detection were utilized to eliminate directly excited TagRFP fluorescence and background cellular autofluorescence, which lasts a fraction of nanosecond, and thus to improve sensitivity of analyses. Furthermore the technique facilitates selective detection of fluorescence, induced by uncleaved acceptor emission. For the first time it was shown that fluorescence resonance energy transfer between sensitized terbium and TagRFP in the engineered construction can be studied via detection of microsecond TagRFP fluorescence intensities. The lifetime and distance distribution between donor and acceptor were calculated using molecular dynamics simulation. Using this data, quantum yield of terbium ions with binding peptide was estimated. 相似文献
80.