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Field electron emission from “polymer-carbon nanotubes” composites as revealed by mass spectrometry

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Field electron emission from “polymer-carbon nanotubes” co...

Usage of global navigation systems for detection of dangerous meteorological phenomena

第18届国际真空大会

作者： o.F. Pozdnyakov E.o. popov A.o. Pozdnyakov Ioffe Physico-Technical Institute 26 PolytekhnicheskayaSt. Petersburg194021Russia Institute of Problems of Mechanical Engineering Bol’shoi pr. 61V/OSt. Petersburg199178Russia

＜正＞The compositions of the polymer–carbon nanotube （PCNT） type have proven to be promising nanostructured materials for FE cathodes characterized by high values of the field electron current.

关键词： polymer-nanotube composites field electron emission mass-spectrometry

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Journal of Measurement Science and Instrumentation 2015年第1期6卷 68-74页

作者： V F Kravchenko o V Kravchenko V I Lutsenko I V Lutsenko D o popov Kotel'nikov Institute of Radio Engineering and Electronics Russian Academy of Sciences Usikov Institute of Radiophysics and Electronics National Academy of Sciences of Ukraine

The method of dangerous meteorological phenomenon detection using the data of coordinate measurement by receivers of global navigation satellite system （GLoNASS） and global positioning system （GPS） is proposed. The possibility of thunderstorm courses and strong clouds detection on data of pseudo-distances and altitudes is shown theoretically and confirmed experimentally.

关键词： dangerous meteorological phenomenon radio-raying global navigation system pseudo-range altitude

Description and analysis of non-stationary signals by nested semi-Markov processes

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Journal of Measurement Science and Instrumentation 2014年第3期5卷 25-32页

作者： V F Kravchenko V I Lutsenko I V Lutsenko D o popov Kotel'nikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences Usikov Institute of Radiophysics and Electronics of National Academy of Sciences of Ukraine

The possibility of describing the time-dependent processes of scattering by underlying surfaces and the clear sky, as well as the seasonal behaviour of the refractive index of troposphere by using nested semi-Markov processes has been consid- ered. Local Gaussian models can be used to describe the process inside each phase state. The possibility of describing the sta- tistics of reflections from the sea and the refractive index by using Kravchenko finite functions has been shown for the first time.

关键词： semi-Markov processes Kravchenko functions atomic functions scattered signal

Empirical model of correction for zenith tropospheric delay

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Journal of Measurement Science and Instrumentation 2014年第4期5卷 20-28页

作者： V F Kravchenko V I Lutsenko I V Lutsenko D o popov A G Laush V N Gudkov Kotel'nikov Institute of Radio Engineering and Electronics Russian Academy of Sciences Usikov Institute of Radiophysics and Electronics of National Academy of Sciences of Ukraine Co Ltd. Navis-Ukraine

The paper considers the possibility of correction of zenith tropospheric delays, and calculates it with the standard model, which takes into account the values of the refractive index of the troposphere at the time of measurement. Based on the experimental research, this empirical model of correction for zenith tropospheric delays can reduce the measurement er- ror of coordinates to about 30 % and altitude to about 40 %.

关键词： zenith tropospheric delays satellite navigation signal global positioning system (GPS) global navigation satel-lite system (GLoNASS)

Three-point method of differential correction of coordinates and pseudo-range in GPS

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Journal of Measurement Science and Instrumentation 2014年第1期5卷 41-45页

作者： V F Kravchenko A G Laush V I Lutsenko I V Lutsenko D o popov 王建园 Kotelnikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences Co Ltd Navis-Ukraine Usikov Institute of Radiophysics and Electronics of National Academy of Sciences of Ukraine 南京航空航天大学(NUAA) 南京210016

This paper presents the interpolation method of generating the differential correction to coordinates and *** a consequence,to improve the quality and stability of the generated correction of amendments,it is advisable to use a system of three reference *** demonstrates the advantages of the interpolation method in comparison with the standard method of differential correction.

关键词： refraction troposphere differential correction satellite navigation systems

Simulator of GNSS signals for testing of space objects receivers in the earth conditions

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Journal of Measurement Science and Instrumentation 2018年第3期9卷 249-256页

作者： Yu Khomenko V F Kravchenko A G Laush V I Lutsenko I V Lutsenkoa Do popova Limited Liability Company ＂NaviS-Ukraine＂ Cherkasy 20708Ukraine Kotel＇ nikov Institute of Raclio Engineering and Electronics of Russian Acaclemy of Sciences Moscow 125009Russia Usikov Institute of Raclioph ysics and Electronics of National Academy of Sciences of Ukraine Kharkiv 61085Ukraine

A technique for testing space object receivers using global navigation satellite system （GNSS） signal simulator of the navigation field is proposed. Its structure consists of two blocks which allow synthesizing the scenario of reciprocal displacement of the receiver relative to navigation satellites and their signals. In the first block, according to the known coordinates of the receiver which are specified in tabular form or analytically, the distances between the receiver and the navigation satellites are calculated as well as their relative velocities. According to these data, the second block synthesizes the signals of navigational travelers with the specified characteristics which are transmitted via the air or cable with a given attenuation to the receiver. This allows testing on the earth receivers for airplanes and space objects under different scenarios of their movement, which not only reduces the risk of problems during the flight, but also avoids significant economic costs. Based on real data obtained by approaching two spacecraft using a simulator, the receiver was tested, which shows the promise of the proposed technology.

关键词： global positioning system GPS) global navigation satellite system (GLoNASS) global navigation satellite system (GNSS) simulator satellite navigation systems (SNS)

Gazeau–Klauder coherent states examined from the viewpoint of diagonal ordering operation technique

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Chinese Physics B 2016年第7期25卷 114-123页

作者： Dusan popov Romeo Negrea Miodrag popov Politehnica University Timisoara Department of Physical Foundations of Engineering 300223 Timisoara Romania Politehnica University of Timisoara Department of Mathematics 300006 Timisoara Romania politehnica University Timisoara Department of Architecture and Urban Planning 300223 Timisoara Romania

In this paper we investigate the Gazeau–Klauder coherent states using a newly introduced diagonal ordering operation technique, in order to examine some of the properties of these coherent states. The results coincide with those obtained from other purely algebraic methods, but the calculations are greatly simplified. We apply the general theory to two cases of Gazeau–Klauder coherent states： pseudoharmonic as well as the Morse oscillators.

关键词： coherent states operator technique density operator

Reduction of friction by normal *** of contact stiffness

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Friction 2017年第1期5卷 45-55页

作者： M.popov V.L.popov N.V.popov Berlin University of Technology Berlin 10623 GermanyTomsk Polytechnic University Tomsk 634050 RussiaTomsk State University Tomsk 634050 Russia Berlin University of Technology Berlin 10623 Germany

The present paper is devoted to a theoretical analysis of sliding friction under the influence of oscillations perpendicular to the sliding *** contrast to previous works we analyze the influence of the stiffness of the tribological contact in detail and also consider the case of large oscillation amplitudes at which the contact is lost during a part of the oscillation period,so that the sample starts to 'jump'.It is shown that the macroscopic coefficient of friction is a function of only two dimensionless parameters-a dimensionless sliding velocity and dimensionless oscillation *** function in turn depends on the shape of the contacting *** the present paper,analysis is carried out for two shapes:a flat cylindrical punch and a parabolic *** we consider 'stiff systems',where the contact stiffness is small compared with the stiffness of the *** role of the system stiffness will be studied in more detail in a separate paper.

关键词： sliding friction out-of-plane oscillation contact stiffness coefficient of friction active control of friction

Reduction of friction by normal oscillations.Ⅱ.In-plane system dynamics

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Friction 2017年第2期5卷 534-535,536页

作者： Xinyu MAo Valentin L.popov Jasminka STARCEVIC Mikhail popov Technische Universit(a)t Berlin Berlin 10623 GermanyTsinghua University Beijing 100084 China Technische Universit(a)t Berlin Berlin 10623 GermanyTomsk Polytechnic University Tomsk 634050 RussiaTomsk State University Tomsk 634050 Russia Technische Universit(a)t Berlin Berlin 10623 GermanyTomsk State University Tomsk 634050 Russia

The influence of out-of-plane oscillations on friction is a well-known phenomenon that has been studied extensively with various experimental methods,e.g.,pin-on-disk ***,existing theoretical models have yet achieved only qualitative correspondence with *** we argue that this may be due to the system dynamics (mass and tangential stiffness) of the pin or other system components being *** paper builds on the results of a previous study [19] by taking the stiffness and resulting dynamics of the system into *** main governing parameters determining macroscopic friction,including a dimensionless oscillation amplitude,a dimensionless sliding velocity and the relation between three characteristic frequencies (that of externally excited oscillation and two natural oscillation frequencies associated with the contact stiffness and the system stiffness) are *** the limiting cases of a very soft system and a very stiff system,our results reproduce the results of previous *** between these two limiting cases there is also a resonant case,which is studied here for the first *** resonant case is notable in that it lacks a critical sliding velocity,above which oscillations no longer reduce *** obtained for the resonant case are qualitatively supported by experiments.

关键词： sliding friction out-of-plane oscillation stiffness system dynamics macroscopic friction coefficient