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Many cryospheric formations on Earth have an inaccessible location. For example, when studying ice sheets located on the water surface, at the initial moment of ice formation, it becomes difficult to take samples. Remote monitoring methods in the microwave range can be used to study such objects. For example, install a microwave radiometer on an unmanned aerial vehicle and use its own thermal radiation from a cryogenic object to record various kinds of features. For radiometric measurements using microwave radiometers, it is necessary to calibrate the measuring device. In this paper, the radiometer calibration method is considered. For these purposes, two objects with known radiative characteristics were measured. The first is fresh open water with a known surface area and thermodynamic temperature against the background of a frozen cloudless atmosphere. The second is a section of the sky reflected from a metal sheet, with the same area. As an example, radiometric measurements of the ice cover of the Ingoda River, located in the Transbaikal Territory (Russia) at a frequency of 34 GHz, were performed. This measurement technique will be useful to specialists in the field of environmental monitoring of cryospheric formations by microwave remote methods in winter.

Remote radiophysical methods using artificial satellites of the Earth allow to determine physical and chemical parameters of the atmosphere. For this purpose, calibration subsatellite measurements are necessary. One of the natural phenomena to be studied is precipitation in the form of snow. This paper presents the results of ground-based measurements of radio-thermal radiation of snow cover at two wavelengths 0.88 cm and 1.35 cm, as well as the results of measurements of the variation of the vertical component of the surface atmospheric electric field strength during snowfall. The measurements were made near the ice-water phase transition temperature. The research site is located in the city of Chita (Russian Federation). A strong influence of air temperature on the measured values, especially at the ice-water phase transition temperature, was found.

The paper presents the results of a study of the own thermal radiation in the infrared range of the Ingoda River, flowing within the city limits of Chita (Russia) A track was built along the river runoff to determine the surface temperature of the object, with a length of 155 km. Space images obtained from Landsat-8 and Landsat-9 Earth remote sensing satellites in channel 10 were used for analysis. In this channel, its own thermal radiation is accepted at wavelengths lying in the range of 10.60…11.19 microns. As a result of the study, it was shown that the optimal time for observing thermal pollution of a river flow is winter time. It is shown that the increase in brightness temperature of the river surface due to the influence of the city in January is on average 6…8 K. This value is not registered in summer. The thermal trace along the Ingoda River from the city is observed over a distance of 7…10 km. Also, one of the results is that not only cities but also settlements with a population of no more than 5000 people affect thermal pollution of water bodies.

The article is devoted to the interpretation of parody, satire, and caricature within the framework of premodern, modern, and postmodern societies. Considering mainly Western European and Russian cases, the researchers conclude that system of regulations and conventions linked the addressee and the addresser. The article compares some of the strategies and reputational capabilities of the satirical weeklies "Charivari", "Punch", "Spark", "Alarm clock" and "Dragonfly", an attempt is made to rank these publications according to the degree of public consent and disturbance of the public peace. Finally, conclusions are drawn about taboos and topics prohibited by the legal or moral law, the appeal to which has a clearly conflicting potential.

La2O3 nanoparticles stabilized on carbon nanoflake (CNF) matrix were synthesized and graphitized to produce core-shell structures La2O3/CNFs@C. Further oxidation of these structures by nitric acid vapors for 1, 3 or 6 h was performed, and surface-oxidized particles La2O3/CNFs@C_x (x = 1, 3, 6) were produced. Bulk and surface compositions of La2O3/CNFs@C and La2O3/CNFs@C_x were investigated by thermogravimetric analysis and X-ray photoelectron spectroscopy. With increasing the duration of oxidation, the oxygen and La2O3 content in the La2O3/CNFs@C_x samples increased. The electronic structures of samples were assessed by electron paramagnetic resonance. Two paramagnetic centers were associated with unpaired localized and mobile electrons and were registered in all samples. The correlation between bulk and surface compositions of the samples and their electronic structures was investigated for the first time. The impact of the ratio between sp2- and sp3-hybridized C atoms, the number and nature of oxygen-containing groups on the surface and the presence and proportion of coordinated La atoms on the EPR spectra was demonstrated. [ABSTRACT FROM AUTHOR]

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The article shows the results of calculations necessary for testing to approve the space qualified electric field probe used in outer space. A special electric field probe calibration setup was developed and manufactured, which allows testing a space qualified electric field probe in the entire measurement range (from ± 0.1 to ± 200 kV/m) under low (-80 °C) and high (+72 °C) temperatures and at reduced pressure of 1.3 · 10-3 Pa (10-5 torr). Metrological tests of the probes batch, calibrated by the space qualified electric field probe calibrator, performed at the verification equipment under normal conditions, showed that the maximum error of the electric field probe does not exceed 15% in the entire measurements range which will increase the accuracy of determining the satellite surface charging parameters and help in designing modern spacecrafts.

This paper presents the results of a parametric experimental investigation aimed at optimizing the body force produced by single dielectric barrier discharge plasma actuators used for aerodynamic flow control. A primary goal of the study is the improvement of actuator authority for flow control applications at higher Reynolds number than previously possible. The study examines the effects of dielectric material and thickness, applied voltage amplitude and frequency, voltage waveform, exposed electrode geometry, covered electrode width, and multiple actuator arrays. The metric used to evaluate the performance of the actuator in each case is the measured actuator-induced thrust which is proportional to the total body force. It is demonstrated that actuators constructed with thick dielectric material of low dielectric constant produce a body force that is an order of magnitude larger than that obtained by the Kapton-based actuators used in many previous plasma flow control studies. These actuators allow operation at much higher applied voltages without the formation of discrete streamers which lead to body force saturation. DOI: 10.2514/1.41588

The article is devoted to determination of roof bolt parameters in coal mine excavations when there is rather high tectonic stress. The work was complicated by the presence of considerable number of fractures in the adjacent rock of seam V-12 in “Severnaya” mine (JSC “Urgalugol”) as well as variable stress field, low roof rock strength and heterogeneity, considerable rock shift during excavations development and maintenance. The article presents the results of horizontal and vertical stress measurements in the rock mass, physical and mechanical properties, roof rock structure and fracturing. According to the results of boreholes study by means of borehole endoscope the authors fully confirmed the forecasted parameters of areas with roof rock discontinuity, the boundaries of unstable rock. The article presents the measurement results of roof rock shift during development face advance. Based on the research, recommendations on excavations development and proper support using were given under conditions of seam V-12 in “Severnaya” mine (JSC “Urgalugol”).

In this paper, the results of flow-control experiments using single dielectric barrier discharge plasma actuators to control flow separation and unsteady vortex shedding from a circular cylinder in crossflow are reported. This work is motivated by the need to reduce landing gear noise for commercial transport aircraft via an effective streamlining created by the actuators. The experiments are performed at [Re.sub.D] = 3.3 x [10.sup.4]. Using either steady or unsteady actuation, Karman shedding is totally eliminated, turbulence levels in the wake decrease significantly, and near-field sound pressure levels associated with shedding are reduced by 13.3 dB. In the case of unsteady plasma actuation, an actuation frequency of [St.sub.D] = 1 is found to be most effective. The unsteady actuation has the advantage that total suppression of shedding is achieved for a duty cycle of only 25%. However, because unsteady actuation is associated with an unsteady body force and produces a tone at the actuation frequency, steady actuation is more suitable for noise-control applications.