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The purpose of the research in this paper is to develop a promising airfield driverless tow truck to increase the economic efficiency of aircraft towing facilities, including unmanned aircrafts as well as to ensure reliable operation in various climatic conditions. The research methods include the analysis of the experience of using such driverless airfield tow trucks abroad, the theory of calculating traction and speed indicators and experimental studies conducted during the creation and study of field tests of devices used to load the driving wheels of a tractor. To achieve the goal, the configuration of the structure being designed and its intended composition are determined analytically. The operation of the designed device in the traction mode is considered, and the characteristic of calculating its indicators when moving along the support surface is presented. The presented material briefly illustrates the process from creating a model of a driverless airfield tow truck to the created design of an existing sample, which will later be used to conduct its full-scale tests and a comprehensive assessment of its strength traction and speed characteristics.

A new method of loop closure based on storage of local maps of obstacles and meant for reducing accumulated localization errors is proposed. The advantage of this method in comparison with the earlier one is in the decreased amount of RAM. Testing results for the developed system and comparisons with analogs are presented.

Rationale : Ageing of population results in an increase in number of aortocoronary bypass interventions in patients with ischemic heart disease aged 65 years and above. This patient group has an increased risk of complications related to systemic inflammatory response to surgical revascularization of the myocardium by on- pump coronary artery bypass (ONCAB). The off-pump coronary artery bypass (OPCAB) enables to avoid complications related to cardiopulmonary bypass; however, there is no consensus on this technique and no clinical guidelines have been developed. Aim : To evaluate short-term results of surgical treatment of elderly patients with ischemic heart disease after OPCAB and after ONCAB. Materials and methods : We performed a retrospective analysis of 61 patients aged above 60 years with multivessel coronary artery disease. The patients from group 1 (n = 31, mean age 72.2 ± 7.3 years) underwent OPCAB, whereas the patients from group 2 (n = 30, mean age 69.3 ± 7.7 years) underwent ONCAB and pharmaco-cold cardioplegia. Results : In the patient group who had underwent OPCAB, there was a significant decrease in the duration of the surgery (4.15 ± 1.2 vs 4.53 ± 1.3 h, p < 0.05), reduction of the duration of mechanical ventilation (11.8 ± 2.3 vs 15.3 ± 1.4 h, p < 0.05), and the number of the transfused RBC doses (0.36 ± 0.9 vs 2.5 ± 1.1 U, p < 0.05). In the early postoperative period, there was a significant difference in the blood loss volume within the 1st day (280 ± 190 mL in group 1 and 359 ± 270 mL in group 2, p < 0.05). The group 1 patients showed a reduction in frequency of heart arrhythmia (4 (12.9%) vs 11 (36.5%) patients, p < 0.05), shorter duration of stay in the resuscitation unit (1.09 ± 0.3 vs 1.46 ± 0.8 days, p < 0.05) and in the department of cardiac surgery (5.06 ± 0.8 vs 7.3 ± 1.1 days, p < 0.05). Conclusion : In the elderly patients, OPCAB could be the intervention of choice allowing for an improvement of short-term postoperative outcomes.

This paper discusses the features of training simulation for solving problems of visual and instrumental observation and observation of the Earth from the Russian Segment of the International Space Station (ISS). Approaches satisfying the requirement of real-time rendering of the digital visual Earth model with a resolution of up to 15 m/texel with viewing angles of 2 to 110° in a simulation of ISS flight are described. A solution is presented which allows simulating camera observations using a positioning system. The characteristics of the developed software and hardware are given.

Malignant tumors represent a serious problem for healthcare system. At this time, an annual incidence of cancer rate has increased both in Russia and around the world. Renal cancer has 2 % in the structure of oncological incidence. However, in many countries we can see significant increase in oncological incidence and associated mortality. Renal cell carcinoma (RCC) takes the 2nd place after prostate tumors by the growth rate of these parameters: each year more than 200 thousand people become ill with RCC all over the world. Cytokine therapy with interleukin-2 and/or interferon alpha was the standard treatment of the advanced renal cell carcinoma until 2005. However, method of the target therapy became widespread in the last decade. This method is based on the directional drug effect on tumor cells which increases efficiency and safety of the therapy. The use of targeted therapy drugs led to a significant increase in survival rate in RCC patients. In the present review we observe clinical efficacy of the drugs used in the 1st and 2nd line of RCC treatment as well as pharmacoeconomic aspects of their application.

Results of dabigatrana etexilat (Pradaxa) use for venous thrombosis prevention after anterior cruciate ligament arthroscopic reconstruction are presented. It is shown that after this type of surgical intervention patients are at risk of thromboembolic complications development. Intake if Pradaxa tablets in dose 220 mg daily for 10 days after surgery enables to avoid thrombosis of lower extremity veins.

The history of the development of the first domestic high-temperature gas-cooled reactor — a unique experimental reactor for testing the core of reactors for nuclear-powered rocket motors — is briefly reviewed. The extraordinary requirements which were imposed on the reactor made it necessary to search for and implement many physical, structural, and technological innovations and to solve complicated scientific-engineering problems during development and startup. Data on the construction and characteristics of the reactor, the arrangement of the bench systems for servicing the reactor, and the results of the first startup and operation over a period of many years are presented.

The history and basic results of work on nuclear rocket motors (NRMs) in Russia are presented. S.P. Korolev, I.V. Kurchatov, M. V. Keldysh, A. P. Aleksandrov et al. stood at the source of the work in this direction. Our NRM reactors used a heterogeneous scheme with a modular core. This enable component-by-component debugging of the reactor experimentally to the required degree of reliability. Ultimately, the costs of the complex tests were minimized, and technical characteristics obtained exceeded those obtained abroad. The energy-release density in the fuel elements reached 30 kW/cm3, and the temperature and rate of heating of the working body (hydrogen) reached 3100 K and 1000 K/sec, respectively.

During a class-II overhaul of its 1719-m3 blast furnace, the blast-furnace shop at ISPAT-Karmet installed a system to continuously monitor the composition of the gases and their distribution over the top of the furnace. The information is sent to a computer monitor. A stationary gas-sampling beam was installed to sample the gas at the neutral line. The beam is connected to an EMG-20-1 gas analyzer by heated pulse lines. The data that is obtained makes it possible to correct the operation of the furnace in real time, which is particularly important when a multi-component charge is being used. Use of the system for continuous monitoring of gas composition has improved smelting conditions and increased furnace productivity by 263 tons/day while saving 5.0 kg of coke per ton of pig iron.

The propagation of a nonmonochromatic wave beam through a lossless dispersive medium is treated in the paraxial approximation. The frequency spectrum of the beam changes in the process because of the finite dimensions and the imperfect spatial coherence of the source. These changes are analyzed. A physical model is offered to explain the basic features of this effect. Methods for compensating for it are discussed. Possibilities for utilizing it are also discussed. The physical meaning of the "scaling law" is discussed.

We have investigated backward stimulated diffusive scattering of light with a time-varying speckle structure by photorefractive crystals in which the nonlinearity mechanism is diffusion-driven. We show that the efficiency and conjugated fraction for this process depend on the ratio of the coherence time to the dielectric relaxation time of the medium.

Numerical ray tracing analysis of slow mode lower hybrid (LH) waves is used to obtain a qualitative description of LH heating in l = 2 torsatrons. The dependences of LH wave propagation and absorption on the plasma density and temperature, the frequency, the parallel wave number spectrum, and the antenna location are determined. The results obtained using a single harmonic model torsatron magnetic field are in qualitative agreement with those obtained for a more realistic field calculated using the Biot-Savart law.

Optical and nonlinear optical properties of LiNaCO3 single crystals in triclinic and hexagonal phases have been investigated. The refractive indexes were measured for triclinic phase by means of prism method. Sellmeier equations and constants were determined.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The team of Aerojet, Energopool and Babcock & Wilcox has prepared a near‐term Nuclear Thermal Rocket Engine (NTRE) concept that takes advantage of mature fuel technology developed in the former Soviet Union. This proven, advanced fuel appreciably shortens the development schedule of this engine for Moon and Mars exploration. Our near term engine has a number of features that provide safety, mission performance, cost and risk benefits, including: (1) High temperature, long life CIS fuel, (2) high pressure, recuperated topping cycle, (3) assured restart, (4) long life, cooled nozzle with thin inner wall, (5) long life turbopumps, (6) heat radiation and electrical power generation, and (7) component integration energy.

Characteristics of stimulated scattering and parametric amplification of light are investigated in the case of nonmonochromatic pumping on the basis of exact analytical solution of some problems. Part I provides a review of publications devoted to stimulated Raman scattering (SRS). Some new results related to backward SRS are presented as well as the theory of SRS in the pump field of random telegraph signal type. Results of theoretical calculations are compared with the existing experimental data.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Experimental study of stimulated diffusion backscattering in photorefractive crystals demonstrates that the phase conjugate component grows faster than other components of the scattered field in the case of pump radiation with a moving speckle structure.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper presents a theory for parametric amplification of light in the case of non- monochromatic pumping. A possibility of conversion of the optical noise into a quasiharmonic signal as a result of Raman scattering in a selective resonator is discussed for the first time.

Theoretical research on acoustic wave generation by the absorption of laser radiation is reviewed. Relations between acoustic fields generated by laser beams in the air and intensity and energy distributions in cross-sections of laser beams are described for the case of finite thermalization time. It is concluded that acoustic methods might be used for the energy and power restoration of spatial distributions in the laser beams, restoration of laser radiation absorption parameters, and testing of absorption kinetic models.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A reflection-grating self-pumped passive ring mirror is experimentally fabricated in a photorefractive KNbO(3) crystal. The observed values of nonlinear reflectivity are as much as 50%, and the response time of the mirror is several milliseconds.

The process flow diagrams presently used for lowand medium-level liquid waste disposal produce large volumes of secondary waste that must be solidified and later buried. The cost of the expensive processes of solidification and burial must be reduced by perfecting precipitation, ion-exchange, evaporation, and other methods of treating liquid radioactive waste. The technical and economic indices of the operation of treatment facilities could be substantially improved if certain engineering procedures and process flow diagrams were employed: elimination of coagulation, breakdown of organic matter using ozone, preliminary desalination of waste by electrodialysis, and extraction of valuable components during waste concentration, and also if the technologies of continuous ion exchange and ultrafiltration were implemented.

The case of pump pulses with Gaussian space-time intensity distributions is considered in the quasistatic approximation. Expressions are obtained for the power, energy, efficiency, and duration of pulses of the nth Stokes component of the stimulated Raman scattering (n = I, 2 ...). Similar calculations are also made for the stimulated Brillouin scattering. Theoretical estimates are obtained of the maximum conversion efficiency in the stimulated Raman scattering; it is shown that the power efficiency is higher than the energy efficiency. The influence of the attenuation of light in matter, length of the scattering region, and spatial profile of the pump beam on the structure of the stimulated Raman spectrum is considered. The computer-calculated dependences of the energy characteristics of the stimulated Raman scattering in the liquid nitrogen on the pump wavelength (1.06, 0.69, and 0.53 μ) are given. It is shown that some of the theoretical estimates obtained are in good agreement with the experimental results.

Transformation of the energy of spatially noncoherent laser radiation into the energy of a diffraction-limited light beam by stimulated Raman scattering (STRS) is considered. The physical mechanism of the effect is analyzed, the conditions for its realization are formulated, and the results are given of experimental investigations and numerical simulation of STRS correction of wavefronts.

Experimental and theoretical investigations were made of the operation of a singly resonant optical parametric oscillator made of a lithium niobate crystal and pumped by the fundamental-frequency radiation from a YAG:Nd laser. An external signal was injected into the oscillator. When the source of this signal was another optical parametric oscillator utilizing a crystal of barium sodium niobate, it was possible to generate narrow-band radiation throughout the tuning range of the singly resonant lithium niobate oscillator: the output power obtained in this case was several times higher than that in the absence of injection and the spectral brightness of the radiation was 103 times higher. This was achieved at the expense of a slight loss (< 10%) of the fundamental-frequency radiation used to pump the barium sodium niobate oscillator.

A theoretical investigation is made of a doubly resonant multimode-pumped optical parametric oscillator (OPO) in both the cw and pulsed stimulated emission regimes. The conditions for efficient conversion of a broad-band pump wave into a narrow-band signal wave are discussed. Allowance for saturation effects is made in the analysis.

A report is given of the observation of stimulated Raman scattering inside the resonator of an optical parametric oscillator with an LiIO3 nonlinear element. It is shown that, under certain conditions, the pump energy can be converted efficiently into the Stokes component of the signal wave in the oscillator. The principal relationships governing the efficiency of this process are found in the quasistatic approximation. An analysis of a simultaneous system of approximate transient equations describing parametric oscillation and stimulated Raman scattering shows that spiky emission is possible. The investigated system is a new and promising modification of a Raman laser with a double optical resonator and a tunable excitation source.

The authors consider the absorption of electromagnetic waves incident on the plasma surface in an electromagnetic trap. The electromagnetic waves are transformed in the plasma resonance region in the transition layer between the plasma and the magnetic field into Langmuir oscillations travelling in this layer towards decreasing densities. The absorption coefficient for waves of frequencies of the order of (but lower than) the maximum Langmuir frequency is of the order of unity. This ensures, in the presence of a metal chamber, effective absorption of the entire super-high-frequency power supplied.

An experimental and theoretical study was made of the maximum efficiency of second harmonic generation in the presence of diffraction effects and stimulated Brillouin scattering.

A theoretical analysis is made of stimulated Raman scattering in which the pump wave is preferentially backscattered due to the influence of the axial anti-Stokes component. The feasibility of achieving this regime is discussed.

A theory is developed of a multimode-pumped optical parametric oscillator emitting a narrow line. It is shown that the efficiency of conversion to parametric frequencies may be close to the efficiency under single-mode pumping conditions. Saturation effects and the shape of the pump pulses are allowed for in the theoretical analysis.

Properties of a niobium-niobium Josephson superconducting point contact (SPC) used as a mixer-multiplier have been investigated experimentally. Conversion of a microwave signal with frequency fs= 127 GHz into a signal with the intermediate frequency fif= 8.6 GHz has been obtained using heterodyne generators with frequencies fh= 136.68, 45, and 6.8 GHz, so that fif= nfh1,2,3 ....20- fswhere n = 1.2, 3.20 are heterodyne harmonics produced in the SPC. Dependences of the conversion efficiency (η n ) on the bias voltage, the heterodyne power and the heterodyne harmonics have been measured. In the case of the second and the twentieth harmonics, the best value of η 20 /η 2 was 0.25. This value is essentially higher than that obtained for the usual (conventional) semiconducting mixer. Performed experiments have demonstrated the perspective of utilization of SPC as a mixer-multiplier in millimeter and submillimeter wavebands.

A theory of transient processes in a parametric light source is developed. Explicit analytic expressions are obtained for the intensities of interacting waves in one- and two-resonator oscillators. These expressions are applicable to pumping pulses of any shape.

An investigation is made of fluctuations of the intensities of optical harmonics generated under resonant conditions by the field of randomly modulated pump radiation. An experimental study is reported of the dependence of the relative variance of the intensity of the third harmonic on the average pump radiation intensity under conditions of a three-photon resonance involving the 3s –5p transition in sodium vapor. The results indicated the possibility of suppressing fluctuations of the harmonic intensity under saturation conditions. A theory explaining this suppression effect is put forward.

An optoacoustic method was used to detect kinetic cooling of air due to absorption of CO2 laser radiation pulses. An increase in the degree of cooling was observed on reduction in the absolute humidity of air. The conditions for detection of this effect in a real atmosphere were formulated.

industrial conditions with unlimited hydrogen sulfide cont/nts and chloride mixtures with (or without) condensed water at temperatures up to 500" C, equipment for production of intermediate products from sulfurous and highly sulfurous stocks; thermal, catalytic and hydrocracking in addition to all the above conditions for loop expansion pieces of other metals (.primary petroleum processing equipment EIX)U, AVT, EIDU+ AVT, AT, GFU, TsFGU)