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The results of numerical study of accuracy of the method of azimuthal structure function for estimation of the dissipation rate of kinetic energy of turbulence from measurements by low energy coherent Doppler lidars are presented. Conical scanning of probing beam of a lidar around the vertical axis is considered. Applicability of the azimuthal structure function method depending on turbulence strength and signal-to-noise ratio is analyzed.

The results of lidar study of wind turbulence in the atmospheric boundary layer in the littoral zone of Lake Baikal are presented. 2D spatiotemporal distributions of the turbulent energy dissipation rate in the presence of atmospheric internal waves and low level jet streams are obtained for the first time.

The results of retrieval of wind speed and direction from measurements of radial velocity by a Stream Line pulsed coherent Doppler lidar using the duo-beam method and conical scanning are presented. These results are compared with data of a sonic anemometer (point sensor).

A passive optical method for measurement of the crosswind velocity averaged over an atmospheric path is developed. The crosswind velocity estimation is based on the correlation algorithm operating with the shifts of energy centroids of images of topographic objects under natural daylight. Testing results of a measurer prototype based on this algorithm are discribed. The wind velocity estimates recorded by passive optical measurer and acoustic weather station are compared. The optimal duration for averaging the mutual correlation function providing the stability of real-time wind measurements is estimated.

The results of comparative experiments on measurement of the crosswind velocity by the passive correlation optical method and with a coherent Doppler wind lidar are analyzed. A crosswind velocity meter, developed at Institute of Atmospheric Optics SB RAS, was used in the passive correlation optical measurements.

The paper presents the results of measurements of parameters of aircraft wake vortices by a Stream Line coherent Doppler lidar during the three-day experiment on the airfield of Tolmachevo Airport. We have analyzed spatial dynamics and evolution of the wake vortices generated by aircrafts of various types: from Airbus A319 passenger aircraft to heavy Boeing 747-8 cargo aircraft entering the landing at Tolmachevo airport. It is shown that Stream Line lidars may well be used to obtain reliable information about the presence and intensity of aircraft wake vortices in the vicinity of а runway.

The problem of dynamic buckling of a bar under the influence of a compressive force is solved with inclusion of inertial and elastic forces in different stages of the process. The duration of the inertial phase is determined. It is shown that in solids and gas-liquid media, the duration of the inertial stage for real parameters of structural members can be longer than the duration of impact loading.

The inverse problem of determining the inhomogeneity laws of a coating of an elastic cylinder that provide the smallest reflection of a plane acoustic wave in a certain angular sector and in a given frequency range. A functional that expresses the reflection intensity is constructed by direct solution of the direct problem, and an algorithm for minimizing it is proposed. Analytical expressions describing the mechanical parameters of the inhomogeneous coating.

The problem of stability of fluid-conveying carbon nanotubes embedded in an elastic medium is investigated in this paper. A nonlocal continuum mechanics formulation, which takes the small length scale effects into consideration, is utilized to derive the governing fourth-order partial differential equations. The Fourier series method is used for the case of the pinned-pinned boundary condition of the tube. The Galerkin technique is utilized to find a solution of the governing equation for the case of the clamped-clamped boundary. Closed-form expressions for the critical flow velocity are obtained for different values of the Winkler and Pasternak foundation stiffness parameters. Moreover, new and interesting results are also reported for varying values of the nonlocal length parameter. It is observed that the nonlocal length parameter along with the Winkler and Pasternak foundation stiffness parameters exert considerable effects on the critical velocities of the fluid flow in nanotubes.

The dynamic response of a clamped L-connected plate and an actively controlled vibratory power flow are studied. The vibratory power flow is suppressed by a piezoelectric patch, which is bonded on the L-connected plate. The electric patch is considered as an actuator. The feedforward least mean square algorithm is used to deduce the optimal piezoelectric patch control moment. Actuator operation with close-to-optimal moments is studied with allowance for the presence of in-plane waves.