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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 aim of the study was to breed highly adaptive pear varieties that combine high ripeness, nutmeg flavor, as well as long-term fruit keeping during storage. In the Research Institute of Horticulture and Medicinal Plants «Zhigulevskie Sady», work on breeding pear varieties with nutmeg flavor was started by S. P. Kedrin in 1934 with the use of the Williams summer variety in breeding work, and later in 1985, this breeding work with the use of qualitative characteristics of the Williams red variety as a donor the work was continued by A. A. Kuznetsov in order to obtain varieties of pears with a nutmeg flavor. In addition to obtaining varieties with the desired taste qualities, the breeding work of the Institute is aimed at obtaining varieties with high adoptive qualities for use as a garden crop in the conditions of the Middle Volga region. In 2021, the Yakhontovaya variety (Volozhka x Williams red) bred at the institute is included in the State Register for the 7th region. The article also provides a brief description of 4 promising varieties of pears with nutmeg flavor well adapted to local conditions. Three varieties: Dar Zhiguley, Muskatka, Yakhontovaya were obtained as a result of distant crosses with the participation of the Ussuri pear (P. ussuriensis M.), and the fourth variety Volshebnitsa is an intervarietal hybrid. All of them belong to the group of early-fruiting varieties. A long period of fruit consumption (1.5-2 months) was observed in Muskatka and Dar Zhiguley varieties. The Yakhontovaya variety has high commodity and consumer qualities. The varieties have a complex of biologically and economically valuable traits and can be used in breeding. The creation of pear varieties with high-quality fruits capable of competing with foreign ones seems to be quite a possible task for breeders.

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.

From the beginning of the NSLS-II project, the vacuum chamber of the NSLS-II storage ring has been optimized to reduce its impedance. The optimization, performed in close collaboration with the Diagnostic, Vacuum, RF, and Mechanical Engineering groups, has been achieved via calculating the impedance of the vacuum chamber components with the use of both analytical and numerical tools, with the numerical computations carried out with the GdfidL code. For reliable NSLS-II operation with the total beam current of 500 mA, each component of the vacuum chamber has been individually optimized to minimize the beam-induced heating and to prevent single-bunch and coupled-bunch instabilities. In this article, the impedance calculation and optimization know-how are summarized for all the chamber components, and the total longitudinal impedance budget is analyzed. As a result of this extensive research and engineering effort, the design beam current of 500 mA has been recently accumulated in NSLS-II without any major problem caused by the collective effects.

A fast and precise technique of local impedance measurement has been developed and tested at NSLS-II. This technique is based on in-phase sine-wave (AC) excitation of four fast correctors adjacent to the vacuum chamber section, impedance of which is measured. The beam position is measured using synchronous detection. Use of the narrow-band sine-wave signal allows us to improve significantly the accuracy of the orbit bump method. Beam excitation by fast correctors results in elimination of the systematic error caused by hysteresis effect. The systematic error caused by orbit drift is also eliminated because the measured signal is not affected by the orbit motion outside the excitation frequency range. In this article, the measurement technique is described and the result of proof-of-principle experiment carried out at NSLS-II is presented.

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.

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.

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 (${\ensuremath{\mu}}_{r}=1$).

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 problems of the optimization of the wooden rod systems is considered. The classification of nodes and connections wooden structures is given. The types of optimization problem are also considered.

Information is given about original Russian high-productivity universal tilling-sowing units.

Consideration of transverse wakefields and impedances due to the tapered vacuum chambers for superconducting mini-gap undulators revealed the existence of trapped modes. To investigate this phenomenon, a series of analytical and numerical calculations were performed for both elliptical and rectangular chambers. A rectangular prototype was built and measured and the experimental results were found to be in very good agreement with theory. Knowledge about the impedance of tapered vacuum chambers is important for the evaluation of transverse instabilities in high-energy accelerators.

It has been established experimentally that the force of cutting feed grain with optimal sharpening angles of the cutting element and pinch angle during a change in the cutting speed from 22 to 46 m/s increases by 1.2 times and for rape seeds by 1.1 times.

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).

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.

National Synchrotron Light Source II (NSLS-II), a new state-of-the-art third-generation light source under construction at Brookhaven National Laboratory is expected to have extremely small emittance and extraordinary beam stability. The mechanical requirements for beam diagnostics and instrumentation are exceptionally challenging. Here we present an overview of the mechanical aspects of some NSLS-II diagnostics as well as the performance levels of some systems currently under development.

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 $d\ensuremath{-}bgb$.

Rectangular-waveguide devices intended for the withdrawal and absorption of high-order modes (HOMs) from the superstructure of the TESLA linear electron–positron collider are investigated. These devices, known as couplers, are set in between the subcavities of the superstructure and at its ends. The HOM couplers investigated are connected to the drift tubes via slots oriented along the tube axis (longitudinal slots), at right angles to the axis (azimuthal slots), and at an angle to the axis. In order to damp the HOMs of both polarizations, two rectangular waveguides are used for each coupler. The results of calculation and experimental investigation of two copper subcavities of the superstructure, each one consisting of seven cells, are presented. The investigations were conducted at room temperature at a frequency of 3 GHz using models.

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.

RF system requirements are derived from machine parameters and beam stability specifications. The conceptual design of the RF system for NSLS-II to meet these requirements is presented, consisting of 500 MHz superconducting main cavities, 1500 MHz pasive SCRF harmonic cavities for bunch lengthening, and the RF power and cryogenic systems..