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The research was carried out in order to assess the winter hardiness of apple varieties of the Oryol and Michurinsky selection, as well as the elite hybrids of the selection of the Scientific Research Institute of Horticulture and Medicinal Plants Zhigulevskie Sady in the conditions of the continental climate characteristic of the Samara region. Freezing of annual branches taken from trees of 1011 years of age was carried out in the laboratory under controlled conditions of a freezer at extreme negative temperatures for the 2nd (40C) and 4th (35C after thaw) components of winter hardiness. After freezing, their damage was assessed in April, the results were compared by years of research. Simultaneously with the assessment of winter hardiness in the laboratory, the general condition of trees of these varieties and elite hybrids was assessed in the field conditions of the experimental garden of the Scientific Research Institute of Horticulture and Medicinal Plants Zhigulevskie Sady, in August 2020 and 2021. The general condition and adaptation to low temperatures of the objects of the study were compared with dependence on the agro-climatic conditions of the growing season on the basis of meteorological data of the Samara GMC. During the study, varieties and elites of apple trees of various breeding with high winter hardiness were identified, surpassing control varieties such as Antonovka obyknovennaya, Kutuzovets, Severniy Sinap and others in this indicator. It is quite logical that winter-hardy apple trees, in the absence of winter damage, may have stronger immunity to diseases and resistance to pests. Therefore, the widespread introduction of new varieties and hybrids into industrial gardening will contribute to the creation of a more favorable agroecological environment in the gardens of the Samara region and the Middle Volga region.

The coupled-bunch instability for arbitrary multibunch configurations is investigated in its generality. The theoretical framework adopted is based on the general eigenvalue analysis based on the known formulas of the complex frequency shifts for the uniform multibunch configuration case. Closed formulas are derived for special cases. For the configuration consisting of a uniform filling pattern with a gap of missing bunches, the theoretical results are found to be in good agreement with measurements of the transverse coupled-bunch instability driven by the resistive wall impedance performed at the NSLS-II storage ring.

Impedance modeling for accelerator applications has improved over the years, largely as a result of advances in simulation capabilities. While this modeling has been successful in reproducing certain measurements, it is still a significant challenge to predict collective effects in real machines. In this paper, we review our approach to impedance modeling and the subsequent simulations of collective effects. We discuss the choice of the electrodynamics codes and the required computer power resources, modeling of the geometric, and resistive wall impedances, their comparison with analytical approaches, and their application for simulating of the collective effects with tracking and beam-induced heating.

The resonant interaction of a bunched particle beam with short-range wakefields is the cause of head-tail instability, which is a major limitation for single-bunch beam intensity in circular accelerators. There are several processes that suppress this type of instability, such as fast chromatic damping and Landau damping due to machine nonlinearity. Beam-based feedback systems (transverse dampers) provide active suppression of the beam oscillations. The combined effect of the transverse dampers and chromaticity is discussed in this article. A brief overview of theoretical and experimental studies of the head-tail instability and its mitigation is presented. Results of experimental studies of the transverse mode coupling carried out at National Synchrotron Light Source-II are compared with the theoretical model.

Transverse head-tail instability is a major limitation for the single-bunch beam current in circular accelerators. Beam-based feedback is one of the potential tools to suppress this type of instability. The feedback systems (transverse dampers) provide active suppression of the beam oscillations by electromagnetic fields, the amplitude of which is calculated in real time from the measured beam position. The effciency of the transverse dampers in combination with various chromaticity settings is discussed., CERN Yellow Reports: Conference Proceedings, Vol. 9 (2020): Proceedings of the ICFA mini-Workshop on Mitigation of Coherent Beam Instabilities in Particle Accelerators, Zermatt, Switzerland, 23–27 September 2019

The yield of grain crops by 25% depends on the quality of soil tillage. The working elements of plough-cultivators that exist today are not able to deal with solid and over-dried soil. This is because a flat ploughshare has a constant cutting angle along its entire length that spalls large pieces of soil. Therefore, to improve the crumbling of soil a wedge-shaped working element with a variable cutting angle is developed. The proposed form of ploughshares for plough-cultivators working elements with increasing cutting angles on each part activates additional forces inside the tilled soil layer. This ensures a greater interaction of soil and its better crumbling; the innovative working element with repeated variable cutting angles activates the internal potential of soil. As a result, it changes its inner structure, and its nutrients are better digestible by plants. The developed working element is 20-50 % more efficient than the series ones as it ensures better crumbling of soil. It is patented in the Russian Federation.

NSLS-II is now one of the brightest synchrotron light sources worldwide, in user operations since 2014. Currently, 20 light-generating insertion devices (IDs) are installed: 3 damping wigglers and 17 undulators of various types. These devices introduce significant distortions into the magnet lattice of the storage ring. For each ID, the distortions have been locally corrected using quadrupole magnets located nearby the ID. The insertion devices have also a significant impact on the electron beam emittance. Precise measurements of the emittance were carried out at the Coherent Hard X-ray beamline for three different lattices: without IDs, with 3 pairs of damping wigglers only, and with all IDs. A minimum horizontal emittance of 0.76 nm was achieved. The radiation energy loss and relative energy spread were also measured using a streak-camera. The measured data show good agreement with analytical formulas and numerical simulations.

в статье рассматриваются существующие проблемы налогового администрирования в условиях цифровизации экономики. Предлагаются стратегические направления развития налоговых органов для решения данных проблем.

Economical cultivation of different soils on different speeds requires working organs with different parameters. Using plows with optimal parameters of plow-bottom surface will allow to minimize the cost of tillage with no loss in quality. Such parameters of working surfaces as setting angles of plowshare, bend of mouldboard and others are considered. Adjustment of working organ of a plow by rotating and offsetting will provide the most useful type of plow-bottom surface and better quality of tillage with the use of a single working organ for different soils and speeds. The paper presents a newly developed way to compare the topology of two plow-bottom surfaces with the use of criterial filter-function, as well as original methods to input the data on the topology of plow-bottom surfaces and to approximate these data by polynomial dependencies for smoothing and providing the unimodality of objective function of optimization when using the Hooke and Jeeves method. The optimal angles of rotation (12 degrees) are obtained whereby the deviations of a comparison plow-bottom surface and a basic one are minimal. According to the agrotechnical and technological requirements on the overlap of operating widths between the working organs, the first working organ of plow should be attached without offset, the second one depending on the realized speed should have an offset of 70 mm, the third - of 140 mm, the fourth - of 210 mm. The practical results of using the developed method for universalization of plow-bottom surface are presented.

Working organs being used currently for subsurface tillage do not comply with agrotechnical requirements. In particular, the crumbling of soil layer is unequal across the width of cutting plane of working organ. The scientific hypothesis is that variable cutting angle along the length of blade improves the crumbling of soil layer. The mathematical model of interaction between the soil and a wedge is proposed. As the result, the theoretical dependencies of resistance force of soil to destruction and of thickness of shear layer on the setting angle of tillage tool are obtained. A set of dihedral wedges with different angles of inclination has been used in experimental studies. The tests have been performed in media with a wide range of physical and mechanical properties (ordinary humus, sand, clay). It is determined experimentally that all media interacting with the wedge have some common characteristics depending on the parameters of wedge, in spite of differences of physical and mechanical properties and the appearance of layer formation. The experimental dependence of equivalent stresses on cutting angle of the wedge is obtained. Experimental and theoretical results agree well with each other. On the basis of these studies, the working organs with variable cutting angle are developed. It is revealed that the blade with variable cutting angle creates more tension in the soil layer than a blade with constant cutting angle. It is experimentally confirmed that the working organs with variable cutting angle along the length of the coulter crumble the layer by 20-50% better than serial working organs. The economic effect of the introduction of working organs with variable cutting angle is 200-1300 rubles per hectare of cultivated area.

The NSLS-II storage ring is designed to operate with superconducting RF-cavities with the aim to store an average current of 500 mA distributed in 1080 bunches, with a gap in the uniform filling for ion clearing. At the early stage of the commissioning (phase 1), characterized by a bare lattice without damping wigglers and without Landau cavities, a normal conducting 7-cell PETRA-III RF-cavity structure has been installed with the goal to store an average current of 25 mA. In this paper we discuss our analysis of coupled-bunch instabilities driven by the Higher Order Modes (HOMs) of the 7-cell PETRA-III RF-cavity. As a cure of the instabilities, we apply a well-known scheme based on a proper detuning of the HOMs frequencies based upon cavity temperature change, and the use of the beneficial effect of the slow head–tail damping at positive chromaticity to increase the transverse coupled-bunch instability thresholds. In addition, we discuss measurements of coupled-bunch instabilities observed during the phase 1 commissioning of the NSLS-II storage ring. In our analysis we rely, in the longitudinal case, on the theory of coupled-bunch instability for uniform fillings, while in the transverse case we complement our studies with numerical simulations with OASIS , a novel parallel particle tracking code for self-consistent simulations of collective effects driven by short and long-range wakefields.

This paper deals with a way of universalizing of ploughshare-moldboard surfaces (PMS) due to spatial rotation to work on different soil types and at various speeds. The paper presents a newly developed way to compare the topology of two ploughshare-moldboard surfaces (PMS) using the filter-function criterion and original methods to input data on the PMS topology and to approximate these data with polynomial dependencies for smoothing and providing the unimodality of the objective function of optimization when using the Hooke-Jeeves method. Thus, the optimal angles of rotation and movement to obtain the minimum deviation of the PMS for comparison and the basic one are found, with the practical results of using the method developed for PMS universalization being presented.

The heat transfer analysis has been performed for the stripline kicker, design of which is used at many accelerator facilities as a part of the transverse bunch-by-bunch feed-back system, including NSLS-II. The experimental data of the electrode temperature have been collected from a special diagnostic stripline designed with six infrared view ports. The temperature analysis is based on the power loss calculations and the loss factor computed by the 3-D electromagnetic simulation code GdfidL. To estimate the power loss, we analyze the real part of the longitudinal impedance and the loss factor for two different regimes. We use the ANSYS finite element code to correlate the temperature with the power loss. Lambertson and Shafer formalisms of the longitudinal and transverse beam impedances are discussed for the simplified stripline geometries. The required characteristic impedances and the geometric factors are determined analytically for the simplified geometries and compared with the results for the designed stripline geometry using the 2-D POISSON code by solving the Laplace’s equation in two dimensions. Lambertson’s equations are compared with numerical results. We introduce the frequency range, within which we can apply the analytical approach.

Novel features of the longitudinal instability of a single electron bunch circulating in a low-emittance electron storage ring are discussed. Measurements and numerical simulations, performed both in time and frequency domain, show a non-monotonic increase of the electron beam energy spread as a function of single bunch current, characterized by the presence of local minima and maxima, where a local minimum of the energy spread is interpreted as a higher-order microwave instability threshold. It is also shown that thresholds related to the same zero-intensity bunch length depend linearly on the accelerating radio frequency voltage. The observed intensity-dependent features of the energy spread, confirmed by measurements with two independent diagnostics methods, i.e. horizontal beam profile measurements by a synchrotron light monitor and photon energy spectrum measurements of undulator radiation, are given a theoretical interpretation by applying a novel eigenvalue analysis based on the linearized Vlasov equation.

В статье рассмотрены показатели психологического благополучия и особенности субъективного неблагополучия молодежи на выборке 167 студентов второго курса Санкт-Петербургского госуниверситета. Выделены метакогнитивные стратегии преодоления субъективного неблагополучия. В качестве мишеней психопрофилактики и коррекции неблагополучия в процессе психолого-педагогического сопровождения студентов могут выступать низкие навыки эмоциональной саморегуляции и низкие коммуникативные навыки. Методики исследования: шкалы психологического благополучия К. Рифф в адаптации Т.Д. Шевеленковой и П.П. Фесенко, авторская анкета, интервью.

Obtained equations allow to determine the influence of soil cultivation depth, characteristics of working organs and used structural materials on the productivity of unit. Optimal values of grasp width and unit motion speed providing maximum performance are defined. Expediency of using units with low power tractors and automatic control, or units in which tractors are not used as means of traction is proved.

An analytical expression of the low-frequency quadrupole impedance for undulators and wigglers is derived and benchmarked against beam-based impedance measurements done at the 3 GeV NSLS-II storage ring. The adopted theoretical model, valid for an arbitrary number of electromagnetic layers with parallel geometry, allows to calculate the quadrupole impedance for arbitrary values of the magnetic permeability ${\ensuremath{\mu}}_{r}$. In the comparison of the analytical results with the measurements for variable magnet gaps, two limit cases of the permeability have been studied: the case of perfect magnets (${\ensuremath{\mu}}_{r}\ensuremath{\rightarrow}\ensuremath{\infty}$), and the case in which the magnets are fully saturated (${\ensuremath{\mu}}_{r}=1$).

One of the important issues of the in-vacuum undulator design is the coupling impedance of the vacuum chamber, which includes tapered transitions with variable gap size. To get complete and reliable information on the impedance, analytical estimate, numerical simulations and beam-based measurements have been performed at Diamond Light Source, a forthcoming upgrade of which includes introducing additional insertion device (ID) straights. The impedance of an already existing ID vessel geometrically similar to the new one has been measured using the orbit bump method. The measurement results in comparison with analytical estimations and numerical simulations are discussed in this paper. © 2014 Published by the American Physical Society.