The structure and texture of the fatigue fracture of a tubing sub made of a ferritic–pearlitic steel are studied. The microstructure is found to be characterized by a small grain size, a high ...edge-dislocation density, and a developed crystallographic rolling texture with a tension texture superposed on it. The growth of grains with the {112}〈111〉 and {114}〈221〉 orientations and the suppression of the {001}〈110〉, {112}〈110〉, and {110}〈001〉 texture components are shown to accelerate fatigue fracture.
The research, which purpose is the development of a motion control system for wheeled agricultural machines, is conducted in Polzunov Altai State Technical University. One of the most important steps ...in this case is the testing of the developed control algorithms. It is advisable to replace the field trials by real-time motion modeling, which allows to significantly reduce financial and time costs. The developed control algorithm can be conditionally divided into global and local regulation. Global regulation must determine the angle of rotation of the steered wheels (or the angle of the frame break) by a deviation from the specified trajectory, which ensures the motion along the specified trajectory. Input parameters are the specified path of motion, the current coordinates of the machine and the projection of speed on fixed axes. Local control provides the implementation of the set value of the angle of rotation of the steered wheels. To the input of the local adjustment program is given the values of the set and current angles of rotation of the wheels and the direction of rotation of the electric motor of the maneuvering device. The algorithm for determining the required angle of rotation of the wheels is based on the method of predicting the position of the wheeled vehicle through the predetermined forecast time. In real-time tests, the wheeled vehicle is replaced by its mathematical model, obtained using the differential equations of plane motion. The complex of equipment provides registration and generation of the necessary parameters for the operation of the control system in real time. The tests were carried out on the experimental stand «steering - front suspension of the vehicle». The front steerable wheels were rotated by an electromechanical maneuvering device to an angle providing movement along a given trajectory. The motion along rectilinear and curvilinear trajectories was modeled taking into account perturbations from the side of the support surface and without them. When moving along a curvilinear trajectory, the deviation from the specified trajectory does not exceed 0,3 meters at a speed of 3,33 m/s. Based on the results of the experiments, it was established that the implemented control algorithm ensures motion along a given trajectory with a sufficient degree of accuracy.
The paper presents the first data on lichen diversity in the Kenozersky National Park (Arkhangelsk Region, Northwest Russia). As a result of the study, 263 species and 1 subspecies of lichens and ...allied fungi were found in the southern part of the national park. Seventeen lichen species are reported for the first time for Arkhangelsk Region. Biatora albidula is a new species for Northwest European Russia. Two recorded species are included in the Red Data Book of Russian Federation and 7 in the Red Data Book of Arkhangelsk Region. Pycnothelia papillaria can be recommended for inclusion to the Red Data Book of Arkhangelsk Region.
The paper presents the results of continuing research of lichen diversity in rocky communities of Windy Belt Ridge (Arkhangelsk Region, NW Russia). Using the method of sample plots and linear routes, ...the communities of the mountain Vysokaya (Volda) were examined, and 270 species and 2 subspecies of lichens and allied fungi were recorded there. A total of 18 lichens are new for the mainland area of Arkhangelsk Region, 35 species are new to the Vodlozersky National Park (Arkhangelsk part) and 9 species are in the Red Data Book of Arkhangelsk Region (2020). Within sample plots (altogether 0.2 ha), 230 species were found, with 41–50% of total species number being presented within one sample plot (0.04 ha). Along the linear route (2 km), 190 taxa were recorded: 43 species were found only on the route (outside the sample plots), which is 16% of the total lichen species number in studied communities. Comparative analysis of the lichen diversity between currently studied mountains (Olovgora, Muroigora, Vysokaya) of the Windy Belt Ridge showed that the high degree of community conservation, rocky type of communities with significant rocky outcrops, as well as landscape heterogeneity determine conditions for a high species diversity of lichens. In total, 343 species of lichens and allied fungi have been found for the studied mountains of the Windy Belt Ridge.
Thirty-one lichen-forming fungi, 12 lichenicolous fungi, and 5 non-lichenized fungi are reported as new for Arkhangelsk Region; 7 species are new for its mainland area. Micarea fallax is reported for ...the first time for Russia; M. laeta and M. pusilla are new for the European part of Russia. The second finding of Nicropuncta rugulosa for Russia is recorded; microconidia are first observed in this species. The records of ten species which have been included in the new edition of the Red Data Book of the Arkhangelsk Region (2020) are presented. Nephromopsis laureri from the Red Data Book of the Russian Federation (2008) and Leptogium rivulare from the IUCN Red List are reported for the first time for Arkhangelsk Region.
A source of x-ray radiation is one of the tools to study equations of state of substances in dynamics. The mobile radiographic bench based on BIM-1500 1 was developed in RFNC-VNIIEF to increase ...output parameters of the x-ray radiation source. From automated control system side, BIM-1500 is a set of six high-voltage generators based on the capacitive energy storage, technological equipment, and elements of a blocking system. This paper considers automated control system of the mobile radiographic bench MCA BIM 1500. It consists of six high-voltage generator control circuits, synchronization subsystem, and block subsystem. The object of control has some peculiarities: high level of electromagnetic noise, remoteness of the control panel from the object of control. In connection with this, the coupling devices are arranged closer to the object of control and performed in the form of a set of galvanically insulated control units, which are combined into a net. The operator runs MCA BIM using the operator's screens on PC or by means of manual control on the equipment in the mode of debugging. The control software provides performance of the experiment in automatic regime in accordance with preset settings. The operator can stop the experiment at the stage of charging the capacitive storage.
The paper presents the results of the ongoing research of lichen diversity in Arkhangelsk Region of Russia, in Vodlozersky National Park which is the largest protected area in the territory of NW ...Russia. In total, 155 species of lichens and allied fungi are recorded for the first time for the Arkhangelsk part of the Vodlozersky National Park, and 69 species – for the whole mainland area of Arkhangelsk Region.
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