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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.

The National Synchrotron Light Source II at Brookhaven National Lab is a third-generation synchrotron radiation facility that has been commissioned in 2014. The facility is based on a 3 GeV electron storage ring, which will circulate 500 mA of beam current at 1 nm rad horizontal emittance. The storage ring is 792 meters in circumference and will accommodate more than 60 beamlines in the final built-out. The beamline sources range from insertion-devices located in straight sections, bending magnets or three-pole-wigglers configured in multiple branches. The NSLS-II storage ring commissioning was successfully completed in July 2014 and the facility delivered the first user light on October 23, 2014. Currently the storage ring reached 300 mA beam current and achieved 1 nm rad of horizontal emittance with 3 sets of Damping Wigglers. At this point six NSLS-II project beamlines are routinely taking photons with beam current at 150 mA. This paper reviews the NSLS-II accelerator design and commissioning experience.

The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source at Brookhaven National Laboratory. During spring/ summer of 2014, the storage ring was commissioned up to 50 mA without insertion devices. In the fall of 2014, we began commissioning of the project beamlines, which included seven insertion devices on six ID ports. Beamlines IXS, HXN, CSX-1, CSX-2, CHX, SRX, and XPD-1 consist of elliptically polarized undulator (EPU), damping wigglers (DW) and in-vacuum undulators (IVU) covering from VUV to hard x-ray range. In this paper, experience with commissioning and operation is discussed. We focus on reaching storage ring performance with IDs, including injection, design emittance, compensation of orbit distortions caused by ID residual field, source point stability, beam alignment and tools for control, monitoring and protection of the ring chambers from ID radiation.

The optimal values for tillage quality are proved to be highly dependent on harvest prices and inputs to obtain the required tillage quality, with an abstract model of the tillage quality being elaborated to establish the existing levels of optimal tillage quality that is highly dependent on harvest prices and the inputs to prepare the soil.

We consider the longitudinal point-charge wakefield, w(s), for an axisymmetric collimator having inner radius b, outer radius d, inner length g, and taper length L. The taper angle {alpha} is defined by tan {alpha} = (d-b)/L. Using the electromagnetic simulation code ECHO, we explore the dependence of the wakefield on a collimator's geometric parameters over a wide range of profiles: from small-angle tapers to step-function transitions. The point-charge wakefield is determined using an approximation introduced by Podobedov and Stupakov. We have found it useful to exhibit the wakefield as a function of the scaled variable s/d{alpha}. For small taper angles, our results illustrate the satisfaction of the longitudinal scaling found by Stupakov, Bane, and Zagorodnov; and for larger taper angles, the breaking of this longitudinal scaling is clearly depicted. The use of the scaled variable s/d{alpha} turns out to be especially well suited to describing the wakefield for a collimator with step-function profile ({alpha} = {pi}/2).

В работе рассмотрена инвариантность моделей механизма управления научно-техническими и социально-организационными системами в проблемных ситуациях на базе прототипов и предложенных решений. Предлагаются блок-схемы функционирования системы анализа ситуации и проектирования ее решения, функционирования системы управления и интеграционной поддержки. Разработана методика оценки инвариантности развитого и базового механизма управления научно-техническими и социально-организационными системами в проблемных ситуациях. Invariance of the models of science-and-technical and social-organizational systems management mechanism in problem situations on the basis of prototypes and ready-made solutions is under the authors attention. Block-schemes of functioning of the system of situation analysis and its decision, and functioning of management and integration support system are put forward. The methodology of invariance assessment of developed and basic mechanisms of science-and-technical and social-organizational systems in problem situations is worked out.

Examples of determination of optimal soil cultivation depth during grain production are considered. Obtained mathematical model permits to determine optimal soil cultivation depth in specific environmental and economic conditions.

We use the program ECHO to study numerically the loss factor of axisymmetric cavities and collimators with and without tapering. We consider a Gaussian driving bunch of length $\ensuremath{\sigma}$, and structures with inner radius $b$, outer radius $d$, cavity gap (or collimator inner length) $g$, and taper length $L$. In all cases we consider a short bunch with $\ensuremath{\sigma}\ensuremath{\ll}b$. For the untapered structures ($L=0$), in certain regimes, we describe our numerical results using the known expressions for a step transition and for the diffraction model. In addition, we identify new regimes where $gl\ensuremath{\sigma}$ and/or $d\ensuremath{-}bl\ensuremath{\sigma}$, for which the data must be described by new phenomenological expressions. For a tapered collimator with $d\ensuremath{-}bgb$, we present a phenomenological formula which accurately describes the dependence of the loss factor on the parameters $\ensuremath{\sigma}$, $b$, $d$, and $L$. This formula also holds for a tapered cavity with $gg{d}^{2}/\ensuremath{\sigma}$ and $d\ensuremath{-}bgb$.

The wakefield and impedance produced by the components of the NSLS-II storage ring have been computed for an electron bunch length of 3 mm rms. The results are summarized in a table giving for each component, the loss factor (kappapar ), the imaginary part of the longitudinal impedance at low frequency divided by the revolution harmonic (ImZpar/n), and the transverse kick factors (kappax,kappay).

A new high-brightness synchrotron light source (NSLS-II) is under design at BNL. The 3-GeV NSLS-II storage ring has a double-bend achromatic lattice with damping wigglers installed in zero-dispersion straights to reduce the emittance below 1 nm. In this paper, we present an overview of the impact of collective effects upon the performance of the storage ring. Subjects discussed include instability thresholds, Touschek lifetime and intra-beam scattering.

CESR-B type superconducting cavities are under consideration for acceleration of the electron beam in the 3 GeV NSLS-II storage ring. In this paper we present detailed investigation of longitudinal and transverse impedance of CESR-B cavity and transitions. Ferrite material is included in impedance analysis. Its effect on short range wakepotential has been studied using GdfidL code. The summary results of loss factors and kick factors are presented for a 3 mm rms bunch length.

In this paper we discuss computation of the coupling impedance of the vacuum chambers for the NSLS-II storage ring using the electromagnetic simulator GdfidL [1]. The impedance of the vacuum chambers depends on the geometric dimensions of the cross-section and height of the slot in the chamber wall. Of particular concern is the complex geometry of the infrared extraction chambers to be installed in special large-gap dipole magnets. In this case, wakefields are generated due to tapered transitions and large vertical-aperture ports with mirrors near the electron beam.

This paper describes plans to upgrade insertion devices (IDs) at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, U.S.A. The aging wiggler (W120) at X25 is being replaced by a 1 m long in-vacuum mini-gap undulator (MGU-X25) optimized for a dedicated macromolecular crystallography program. A new, 1/3 m long, undulator (MGU or SCU-X9), will be installed between a pair of RF cavities at X9, and will serve a new beamline dedicated for small angle x-ray scattering (SAXS). Both IDs will have provision for cryocooling the NdFeB hybrid arrays to 150K to raise the field and K-value and to obtain better spectral coverage. Design issues of the devices and other considerations, especially magnetic measurement at low temperature, will be discussed.

The vertical impedances of the preliminary designs of National Synchrotron Light Source II (NSLS-II) Mini Gap Undulators (MGU) are calculated by means of GdfidL code. The Transverse Mode Coupling Instability (TMCI) thresholds corresponding to these impedances are estimated using an analytically solvable model.

NSLS-II is a 3 GeV ultra-high brightness storage ring planned to succeed the present NSLS rings at BNL. Ultra-low emittance combined with short bunch length means that it is critical to minimize the effects of Touschek scattering and coherent instabilities. Improved lifetime and stability can be achieved by including a third-harmonic RF cavity in the baseline design. This paper describes the required harmonic RF parameters and the expected system performance.

Die Arbeit behandelt eine planare 30 GHz Beschleunigerstruktur als neue Alternative zu einer Struktur, die im Compact Linear Collider (CLIC) beim Forschungszentrum CERN in Genf angewendet wird. Die Anforderungen an die planare Beschleunigerstruktur entsprechen dabei den Anforderungen an die CLIC-Struktur. Zur Verbesserung ihrer HF-Eigenschaften mussten zwei wichtige Aufgaben gelöst werden: 1) Die Dämpfung von höheren Moden und 2) die Steigerung der Durchschlagsfestigkeit auf der Irisoberfläche der Resonator. Zur Feststellung des Einflusses der höheren Moden wurde das transversale Wakepotential berechnet. Entsprechend den Anforderungen muss es für einen zeitlichen Abstand zwischen den Ladungspaketen von 0.67 ns um den Faktor 100 unterdrückt werden. Für die numerischen Simulationen wurde das 3-dimensionale Feldberechnungsprogramm GdfidL verwendet. Zur Unterdrückung der höheren Moden wurden zwei Strukturvarianten entwickelt, die den obigen Forderung entsprechen, erstens eine Struktur bestehend aus einer Kombination von Dämpfungshohlleitern zweitens eine verstimmte Struktur. Zur Verminderung der hohen Feldstärke auf der Irisoberfläche der Koppelzellen wurde eine symmetrische Ein- und Auskoppeleinrichtung verwendet, bei welcher die HF-Leistung symmetrisch eingespeist wird. Zur Steigerung der Duchschlagsfestigkeit der Struktur wurde eine abgerundete Irisform vorgeschlagen. Zur messtechnischen Überprüfung im Laboratorium wurde ein auf 10 GHz skaliertes Modell der Struktur mit konstanter Impedanz hergestellt. Die Messergebnisse stimmten hierbei mit den numerischen Simulationen sehr gut überein.

Some modifications of a Rectangular Waveguide HOM couplers for TESLA superstructure have been investigated. These RWG HOM couplers are to be installed between the cavities of the superstructure and also at the both ends of it. We investigated a RWG HOM coupler attached to the beam pipe through the slots orientated along beam pipe axis (longitudinal slots), perpendicular to it (azimutal slots) and at some angle to this axis. For dipole modes of both polarizations damping two RWG in every design were used. This paper presents the results obtained for scaled-up setup at 3 GHz at room temperature. The advantages of HOM coupler with longitudinal slots for damping dipole modes and compact HOM coupler with slots at some angle to the axis are shown. Arrangement of HOM coupler in cryostat and heating due to HOM and FM losses are presented. Calculations and design of the feeding RWG coupler for superstructure are also presented., LINAC2000 TUA13, 3 pages, 4 figures, 3 tables