Now showing items 15-34 of 1050

    • Biomechanical properties of composite compact-porous titanium produced by electric discharge sintering 

      Minko, D.; Belyavin, K.; Sheleg, V. (2017)
      The main disadvantage of currently used endosteal implants is their unsatisfactory biostable performance. Under action of functional stress caused by flaws of the design or lower mechanical characteristics the areas of stresses extreme concentration exceeding strength limits of bone tissue appears in the bone surrounding the implant that leads to the tearing away the implant. The ...
      2018-03-15
    • Bristlebots in swarm robotics - new approaches in modeling and agent development 

      Becker, F.; Zeidis, I.; Zimmermann, K.; Cuellar, F.; Pozo Fortunić, J. E.; Lysenko, V.; Minchenya, V. T. (2016)
      Bristlebots are vibration-driven mobile robots. They are characterized by small size, high speed, simple design and low costs of production and application, which are ad- vantageous qualities for agents of swarm robotic systems. In this paper, new ap- proaches in modeling and development of swarm agents are given. It is shown that a simple mass point model can be used to simulate ...
      2019-12-19
    • Broadly tunable femtosecond mode-locking in a Tm:KYW laser near 2 μm 

      Lagatsky, A. A.; Calvez, S.; Gupta, J. A.; Kisel, V. E.; Kuleshov, N. V.; Brown, C. T. A.; Dawson, M. D.; Sibbett, W. (Optical Society of America, 2011)
      Efficient mode-locking in a Tm:KY(WO4)(2) laser is demonstrated by using InGaAsSb quantum-well SESAMs. Self-starting ultrashort pulse generation was realized in the 1979-2074 nm spectral region. Maximum average output power up to 411 mW was produced around 1986 nm with the corresponding pulse duration and repetition rate of 549 fs and 105 MHz respectively. Optimised pulse durations ...
      2018-03-15
    • Business valuation in emerging markets 

      Trifonov, N. (TAF, 2008)
      Problems of peculiarities of business valuation techniques in emerging markets are discussed in the paper.
      2014-02-05
    • Calculation of Residual Magnetic-Field Distributions upon Hysteretic Interference of a Pulsed Magnetic Field 

      Pavlyuchenko, V. V.; Doroshevich, E. S.; Pivovarov, V. L. (2015)
      Equations that are used for the calculation and distributions of the electrical voltage U(t) output from a magnetic-field transducer as it scans a discrete magnetic medium with recorded residual magnetic fields, which were produced in it by acting individual magnetic-field pulses with opposite-polarity surges, are reported. The distributions were obtained via the Delphi programming ...
      2017-11-23
    • Central and Eastern European Countries 

      Trifonov, N. (Kluwer academic publishers, 2002)
      Trifonov, N. Central and Eastern European Countries / N. Trifonov // Real estate education throughout the world: past, present and future. – Kluwer academic publishers: 2002. – Chapter 5. – Р. 61-88.
      2014-01-28
    • Changing of technical and operational road parameters caused by traffic load and climatic factors 

      Leonovich, I.; Melnikova, I. (2014)
      Climatic factors and car wheels are the reasons of changes in road condition: deformations of subgrade, cracks, potholes and rut appear, roughness and safety are deteriorating, and the strength of the road structure reduces. In our opinion, cracks in the road structure are of particular importance. The appearance of cracks causes the destruction of the whole road structure during ...
      2018-03-10
    • Choosing The Risk Curve Type 

      Vlasenko, O.; Kozlov, S. (2009)
      Dialectics of categories of risk and return are becoming increasingly important in business process. The knowledge of risk indices allows to shape the judgement and make a decision. The provided risk-management method lets to make more reasonable and adequate managing decisions. The paper provides the substantiation of necessity of the enterprise risk level integral estimation. ...
      2018-03-15
    • Collisional self-broadening coefficients and probabilities of spontaneous emission of the CO2 1000–0001 transition lines 

      Arshinov, K. I.; Krapivnaya, O. N.; Nevdakh, V. V. (Pleiades Publishing, 2017)
      Using a tunable frequency-stabilized CO2 laser, the pressure dependences of unsaturated absorption coefficients (AC) are measured in pure carbon dioxide in the pressure range from 5 to 30 Torr, where the spectral line shape is described by the Voigt profile. The absorption coefficients are measured in the centers of R(8), R(22), R(34), P(22), and P(36) spectral lines of the ...
      2022-07-29
    • Compact 0.7 mJ/11 ns eye-safe erbium laser 

      Vitkin, V. V.; Polyakov, V. M.; Kharitonov, A. A.; Buchenkov, V. A.; Rodionov, A. Yu.; Zhilin, A. A.; Dymshits, O. S.; Loiko, P. A. (2016)
      We report on the development of a compact diode-end-pumped eye-safe (similar to 1.54 mu m) passively-cooled Er, Yb:glass laser. The design of this laser is facilitated by the use of a double-pass pumping scheme and a special ZrO2 diffuse reflector for a uniform pump distribution. In the free-running mode, this laser generates 8.2 mJ/3 ms pulses with a slope efficiency of 15%. ...
      2018-02-27
    • Compact passively Q-switched diode-pumped Tm:KY(WO4)2 laser with 8 ns/30 μJ pulses 

      Gaponenko, M. S.; Onushchenko, A. A.; Kisel, V. E.; Malyarevich, A. M.; Yumashev, K. V. (2012)
      A compact diode-pumped solid-state Tm:KY(WO4)2 laser with cavity length of 1 cm passively Q-switched with a PbS-quantum-dot-based saturable absorber is presented. The laser operates at the wavelength of 1.94 ¹m and produces pulses with duration of 8 ns and energy of 30 ¹J at the repetition rate up to 4.2 kHz. The maximum output power of 120 mW is achieved at incident pump power ...
      2018-03-18
    • Competition between electron transfer and energy migration in self-assembled porphyrin triads 

      Zenkevich, E. I.; Willert, A.; Bachilo, S. M.; Rempel, U.; Kilin, D. S.; Shulga, A. M.; Borczyskowski, C. von (2001)
      The photoinduced electron transfer (ET) and the energy migration (EM) processes have been studied in liquid solutions and polymeric (PMMA) films for the triads consisting of the Zn-octaethylporphyrin chemical dimer (the energy and electron donor, D) and dipyridyl substituted tetrapyrrole extra-ligands (porphyrins, chlorin, tetrahydroporphyrin) as the acceptors, A. On the basis ...
      2017-05-26
    • Complexation and interchromophoric interactions in self-organized porphyrin and chlorin triads 

      Chernook, A. V.; Shulga, A. M.; Zenkevich, E. I.; Rempel, U.; Borczyskowski, C. von (1996)
      Spectral properties and equilibrium constants of multimolecular complexes (triads) formed by 2-fold coordination of dipyridyl-substituted free bases of porphyrin, chlorin, or tetrahydroporphyrin with Zn-porphyrin and Zn-chlorin dimers bridged by either of two different spacers between the monomeric entities have been studied in methylcyclohexane at room temperature. The ability ...
      2017-05-18
    • Composite Materials for Steel Cutting and Concrete Crushing 

      Usherenko, Y.; Usherenko, S.; Yazdani, J. (2017)
      The steel based on composite material, created by the stitching of steel matrix by a flow of powder particles. Stitching process implemented in conditions of super deep penetration (SDP) which provides a penetration of the powder particles at speed 1000 m/s on depth up to hundred millimeters. Due to the interaction between the particles and the steel matrix at pulsating pressureabove ...
      2018-03-10
    • Concentration effects in pigment solutions 

      Gurinovich, G. P.; Losev, A. P.; Zenkevich, E. I. (1978)
      Gurinovich, G. P. Concentration effects in pigment solutions / G. P. Gurinovich, A. P. Losev, E. I. Zenkevich // Spectroscopy Letters. – 1978. – Vol. 11, № 7. – P. 493-511.
      2017-05-18
    • Constructive Theory of Scalar Characteristic Equations of the Theory of Radiation Transport: II. Algorithms for Finding Solutions and Their Analytic Representations 

      Rogovtsov, N. N. (2015)
      We present methods for finding discrete spectra and derive analytic expressions for the eigenfunctions of scalar characteristic equations of the theory of radiation transport. We obtain new two-term recursion formulas and analytic representations for solutions of infinite tridiagonal systems of linear algebraic equations. We obtain analytic forms of the resolvents of scalar ...
      2017-11-23
    • Continuous-wave and Q-switched operation of a compact, diode-pumped Yb3+:KY(WO4)2 planar waveguide laser 

      Bain, F. M.; Lagatsky, A. A.; Kurilchick, S. V.; Kisel, V. E.; Guretsky, S. A.; Luginets, A. M.; Kalanda, N. A.; Kolesova, I. M.; Kuleshov, N. V.; Sibbett, W.; Brown, C. T. A. (Optical Society of America, 2009)
      A diode-pumped LPE-grown Yb:KYW planar waveguide laser is demonstrated in a microchip monolithic cavity configuration. Output powers as high as 148mW and thresholds as low as 40mW were demonstrated during continuous-wave operation. Pulses of 170ns duration with maximum pulse energy of 44nJ at a 722kHz repetition rate were generated when Q-switched using a semiconductor saturable ...
      2012-01-23
    • Controlling the characteristics of photovoltaic cells based on their own semiconductors 

      Vorobey, R. I.; Gusev, O. K.; Tyavlovsky, K. L.; Svistun, A. I.; Shadurskaya, L. I.; Yarzhembitskaya, N. V.; Kierczynski, K. (Wydawnictwo SIGMA, 2015)
      The features of photovoltaic cells with their own photoconductivity in semiconductors with deep-level multiply-charge impurity have been considered. The use of such structures can significantly extend the dynamic range of sensitivity and gain new functional properties of single-element photoelectric receivers. Photovoltaic converters based on semiconductors with deep-level ...
      2022-07-13
    • Cooperative up-conversion in Eu3+,Yb3+-doped SiO2–PbO–PbF2–CdF2 oxyfluoride glass 

      Loiko, P. A.; Rachkovskaya, G. E.; Zakharevich, G. B.; Kornienko, A. A.; Dunina, E. B.; Yasukevich, A. S.; Yumashev, K. V. (Elsevier, 2014)
      Novel oxy fluoride glass doped with YbF3 and Eu2O3 is synthesized in the SiO2–PbO–PbF2–CdF2 system by melt quenching technique. Its physical properties, as well as the optical absorption of Eu3+ and Yb3+ ions are studied. Spectroscopic properties of Eu3+ ions are modeled within modified Judd–Ofelt theory, yielding absorption oscillator strength, luminescence branching ratios and ...
      2016-01-05
    • CW and Q-switched diode-pumped laser operation of Yb 3+:NaLa(MoO4)2 

      Mandrik, A. V.; Troshin, A. E.; Kisel, V. E.; Yasukevich, A. S.; Klavsut, G. N.; Kuleshov, N. V.; Pavlyuk, A. A. (Springer, 2005)
      Continuous wave (CW) and Q-switched diode-pumped laser operation of Yb3+:NaLa(MoO4)2 single crystal was to our knowledge, demonstrated for the first time. A CW output power of 220 mW and slope efficiency of 46% were obtained. Q-switched laser operation was achieved with a pulse duration of 60 ns average output power of 70mW and slope efficiency of 22%.
      2016-03-24