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Highly transparent ytterbium doped yttrium lanthanum oxide ceramics

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Journal of Rare Earths 2014年第3期32卷 254-258页

作者： M.Ivanov Yu.Kopylov v.kravchenko 李江 A.Medvedev 潘裕柏 Institute of Electrophysics UrB of RAS 106Amundsena 620016 Ekaterinburg Russia Institute of Radioengineering and Electronics named after v.A. Kotelnikov RAS Vvedensky Sq. 1 Fryazino Moscow region 141120 Russia Shanghai Institute of Ceramics Chinese Academy of Science Ural Federal University 19 Mira 620002 Ekaterinburg Russia

To prepare ytterbium doped lanthania yttria nanopowder a method of laser evaporation of mixed oxides was used. After calcinations of the powder at 1200 ℃ a pure single-phase solid solution yb3＋：（LaxY1-x）2O3 was formed in the nanoparticles. Influence of lanthanum oxide as an isovalent additive on the yttria structure was investigated. The lanthanium ions were proved to be a good aid to sinter yttria ceramics doped with Yb3＋ at moderate temperatures about 1650 ℃. The ceramics with relative density higher than 99.99% and grain size about 40 μm were fabricated. Full transmittance of 1.8 mm thick Yb0.11 La0.23Y1.66O3 ceramics reached 82.5% at 800 nm. This material could be a good gain medium for ytterbium high power pulse lasers.

关键词： RE-doped ceramics nanopowders ytterbium oxide transparency

Usage of global navigation systems for detection of dangerous meteorological phenomena

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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

Prouhet-Thue-Morse sequence and atomic functions in applications of physics and techniques

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Journal of Measurement Science and Instrumentation 2015年第2期6卷 128-141页

作者： victor F kravchenko Oleg v kravchenko Yaroslav Y Konovalov Kotelnikov Institute of Radio-engineering and Electronics Russian Academy of Sciences Bauman Moscow State Technical University Scientific and Technological Center of Unique Instrumentation

In present article a number of results are described in a systematic way concerning both signal and image processing problems with respect to atomic functions theory and Prouhet-Tbue-Morse sequence.

关键词： atomic functions Prouhet-Thue-Morse sequence digital signal processing image processing

ON THE EXPERIMENTAL INvESTIGATION OF AIR—BREATHING ENGINE OF NEW SCHEMES

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Chinese Journal of Aeronautics 1992年第1期 1-4页

作者： Bakulev v I kravchenko I v Moscow Aviation Institute

The use of hydrogen as the fuel of hybrid engine has a high value of specificparameters and wide prospect in the future in aerospace field. Three schemes of this kindof engine are proposed in this paper: （1）《The First-borne》 turbo-rocket engine withgasified and pre—heated （in heat exchanger） hydrogen as a working fluid of turbine. （2）The gas generator hydrogen bypass turbo-jet engine with an afterburner. （3） The enginewith the same above scheme but having an additional heat exchanger behind *** throttle characteristic of 《First-borne》 scheme of engine has been tested by usinga small-size engine on a special test rig and equipment. The investigation results showthat the performance of this engine under F= const, Tc（?）ch= Const, FThroat= var programeof regulation is most *** addition, the variation of specific thrust Pspec, specific fuel consumption Cspecandthrust P are shown and explained.

关键词： area BREATHING ENGINE OF NEW SCHEMES ON THE EXPERIMENTAL INvESTIGATION OF AIR line

Sensors for control of water transparency in optical and microwave ranges

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Journal of Measurement Science and Instrumentation 2018年第4期9卷 354-359页

作者： v F kravchenko E v Krivenko v I Lutsenko I v Popov Kotel’nikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences Moscow 125009 Russia Bauman Moscow State Technical University Moscow 105005 Russia Scientific and Technological Center of Unique Instrumentation of Russian Academy of Sciences Moscow 119992 Russia Usikov Institute of Radiophysics and Electronics of National Academy of Sciences of Ukraine Kharkiv 61085 Ukraine

In the face of deteriorating environmental conditions in the world,water quality control is an urgent *** can be solved by creating sensors with high accuracy and low cost,which requires the development of fundamentally new radiophysical methods that take advantage of the optical,microwave and millimeter wavelengths that have a significantly greater sensitivity to low concentrations of pollutants and a lower *** article presents prototypes of measuring cells of the microwave and optical ranges as well as the results of an experimental study of water of various degrees of pollution with their *** results show that the use of the highly sensitive method of capillary-waveguide resonance makes it possible to detect the presence of micro impurities in water with concentrations up to0.1%and to identify water even from sources of various natural *** addition,the use of measurements at several frequencies in the optical range will make it possible to solve the problem of creating water control sensors with high sensitivity to pollution and low *** can be concluded that the possibility of complex use of multiwave sensors(optical,infrared and microwave ranges)allows to increase the sensitivity and reliability of water quality assessment.

关键词： optical sensor light attenuation in the medium optical transparency capillary-waveguide resonator dielectric characteristics Q-factor and depths of resonance absorption

Nonequidistant two-dimensional antenna arrays based on Latin squares

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Journal of Measurement Science and Instrumentation 2019年第1期10卷 38-48页

作者： v F kravchenko v I Lutsenko I v Popov LUO Yi-yang Kotel’nikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences Moscow 125009Russia Usikov Institute of Radiophysics and Electronics of National Academy of Sciences of Ukraine Kharkiv 61085Ukraine v.N.Karazin Kharkiv National University Kharkiv 61022Ukraine

Non-equidistant sparse antenna arrays constructed on the basis of Latin squares are considered. A method for their construction and a synthesis algorithm are proposed,and the properties of two-dimensional antennas based on them,which ensure,at a high degree of rarefaction,a sufficiently small lateral radiation are studied. The features and main characteristics of such antennas are studied.

关键词： non-equidistant antenna array Latin square compound squares covered frequencies

On the realization of seismic microzonation of Almaty (Kazakhstan) in ground accelerations based on the “continual” approach

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Geodesy and Geodynamics 2020年第1期11卷 56-63页

作者： N.v.Silacheva U.K.Kulbayeva N.A.kravchenko Institute of Seismology AlmatyKazakhstan

Seismic microzonation for Almaty city for the first time use probabilistic approach and hazard is expressed in terms of not only macroseismic intensity,but also Peak Ground Acceleration(PGA).To account for the effects of local soil conditions,the continual approach proposed by ***[1,2]was used,in which soil coefficients are a function of the continuously changing seismic *** coefficients were calculated using the new data of geological and geophysical surveys and findings of previous geotechnical *** used approach made it possible to avoid using soil categories and a jump change in characteristics of soil conditions and seismic *** developed seismic microzonation maps are prepared for further introduction into the normative documents of the Republic of Kazakhstan.

关键词： Seismic microzonation maps Peak ground acceleration Soil conditions Seismic rigidity Continual theory

Probabilistic seismic hazard assessment of Kazakhstan and Almaty city in peak ground accelerations

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Geodesy and Geodynamics 2018年第2期9卷 131-141页

作者： N.v.Silacheva U.K.Kulbayeva N.A.kravchenko Institute of Seismology National Center for Seismological Observations and Research

As for many post-soviet countries, Kazakhstan’s building code for seismic design was based on a deterministic approach. Recently, Kazakhstan seismologists are engaged to adapt the PSHA(probabilistic hazard assessment) procedure to the large amount of available geological, geophysical and tectonic Kazakh data and to meet standard requirements for the Eurocode 8. The new procedure has been used within National projects to develop the Probabilistic GSZ(General Seismic Zoning) maps of the Kazakhstan territory and the SMZ(Probabilistic Seismic Microzoning) maps of Almaty city. They agree with the seismic design principles of Eurocode 8 and are expressed in terms of not only seismic intensity,but also engineering parameters(peak ground acceleration PGA). The whole packet of maps has been developed by the Institute of Seismology, together with other Kazakhstan Institutions. Our group was responsible for making analysis in PGA. The GSZ maps and hazard assessment maps for SMZ in terms of PGA for return periods 475 and 2475 years are considered in the article.

关键词： Probabilistic seismic hazard assessment Seismic zoning map Peak ground acceleration Seismic sources Seismotectonic setting Seismic regime Ground motion prediction equations

Nonequidistant two-dimensional antenna arrays based on magic squares

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Journal of Measurement Science and Instrumentation 2017年第3期8卷 244-253页

作者： v F kravchenko v I Lutsenko I v Lutsenko I v Popov LUO Yi-yang A v Mazurenko Kotel’nikov Institute of Radio Engineering and Electronics of Russian Academy of Sciences Moscow 125009Russia Usikov Institute of Radio Physics and Electronics of Natioanl Academy of Sciences of Ukraine Kharkiv 61085 Ukraine Zhukovsky National Aerospace University-Kharkiv Aviation Institute Kharkiv 61070Ukraine

New methods of synthetizing nonequidistant sparse antenna arrays based on the properties of magic squares are *** methods of construction and algorithms of synthesis of two-dimensional antennas based on them providing a high degreeof dilution and sufficiently small side radiation are *** methods for construction of such antennas and their maincharacteristics are considered.

关键词： magic squares nonequidistant sparse antenna arrays two-dimensional antenna arrays