Full Rotation Research Articles

Comparative analysis of electromagnetic parameters and power interactions in a large turbogenerator in asymmetric load mode

Purpose. Presentation of the results of a rotating magnetic field numerical calculation of a turbogenerator in an asymmetric load mode within its standard limitations. Methodology. The calculation of the rotating magnetic field at full rotation of the rotor is carried out by the finite element method according to the FEMM program. Calculations are automated by controlling the program using Lua script. Results. Calculations are carried out for a 325 MW turbogenerator. The temporal functions of magnetic flux linkage and the corresponding EMF of the rotor winding and phase stator windings were obtained, the power processes in the ferromagnetic core of the stator of the turbogenerator were analyzed, namely the force actions on the teeth and on the core as a whole, the pulsations of the electromagnetic moment and the time functions of its variable component. For a more detailed illustration of the results, similar calculations are performed for the symmetric load of the turbogenerator. Practical value. Analysis of the operation of the TG with an unbalanced load showed problems of power and electromagnetic nature. It is shown that the time functions of the forces acting on the teeth of the stator core are almost the same as those with a symmetrical load, but the compressive forces acting on the core have increased. It is determined that the pulsations of the electromagnetic moment reach 17% of its average value.

What influences the long-term development of mixtures in British forests?

Abstract Six experiments were established between 1955 and 1962 in different parts of northern and western Britain which used replicated randomized block designs to compare the performance of two species 50:50 mixtures with pure stands of the component species. The species involved were variously lodgepole pine (Pinus contorta Dougl.), Japanese larch (Larix kaempferi Lamb. Carr.), Scots pine (Pinus sylvestris L.), silver birch (Betula pendula Roth.), Sitka spruce (Picea sitchensis Bong. Carr.) and western hemlock (Tsuga heterophylla Raf. Sarg.). The first four species are light demanding, while Sitka spruce is of intermediate shade tolerance and western hemlock is very shade tolerant: only Scots pine and silver birch are native to Great Britain. In three experiments (Bickley, Ceannacroc, Hambleton), the mixtures were of two light-demanding species, while at the other three sites, the mixture tested contained species of different shade tolerance. The experiments were followed for around 50 years, similar to a full rotation of even-aged conifer stands in Britain. Five experiments showed a tendency for one species to dominate in mixture, possibly reflecting differences in the shade tolerance or other functional traits of the component species. In the three experiments, the basal area of the mixtures at the last assessment was significantly higher than predicted based on the performance of the pure stands (i.e. the mixture ‘overyielded’). In two of these cases, the mixture had had a higher basal area than found in the more productive pure stand indicating ‘transgressive overyielding’. Significant basal area differences were generally more evident at the later assessment date. The exception was in a Scots pine: western hemlock mixture where greater overyielding at the earlier date indicated a nursing (‘facilitation’) effect. In the remaining experiments, the performance of the mixture conformed to predictions from the growth of the component species in pure stands. Taken overall, the results suggest that functional traits can be used to interpret the performance of mixtures but prediction of the outcome will require better understanding of the interplay between species and site characteristics plus the influence of silvicultural interventions.

Modeling inner boundary values at 18 solar radii during solar quiet time for global three-dimensional time-dependent magnetohydrodynamic numerical simulation

We develop an empirical model of the solar wind parameters at the inner boundary (18 solar radii, Rs) of the heliosphere that can be used in our global, three-dimensional (3D) magnetohydrodynamic (MHD) model (G3DMHD) or other equivalent ones. The model takes solar magnetic field maps at 2.5 R, which is based on the Potential Field Source Surface, PFSS model and interpolates the solar wind plasma and field out to 18 Rs using the algorithm of Wang and Sheeley (1990). A formula (V18Rs = V1 + V2fsα) is used to calculate the solar wind speed at 18 Rs, where V1 is in a range of 150–350 km s−1, V2 is in the range of 250–500 km s−1, and “fs” is the magnetic flux expansion factor derived from the Wang and Sheeley (WS) algorithm at 2.5 R. To estimate the solar wind density and temperature at 18 Rs, we assume an incompressible solar wind and a constant total pressure. The three free parameters are obtained by adjusting simulation results to match in-situ observations (Wind) for more than 54 combinations of V1, V2 and α during a quiet solar wind interval, i.e., the Carrington Rotation (CR) 2082. We found that VBF = (200 ± 50) + (400 ± 100) fs−0.4 km/s is a good formula for the quiet solar wind period. The formula was also good to use for the other quiet solar periods. Comparing results between WSA (Arge et al. 2000, 2004) and our model (WSW-3DMHD), we find the following: i) The results of using VBF with the full rotation (FR) data as input to drive the 3DMHD model is better than the results of WSA using FR, or daily updated. . ii) The WSA model using the modified daily updated 4-day-advanced solar wind speed predictions is slightly better than that for WSW-3DMHD. iii) The results of using VBF as input to drive the 3DMHD model is much better than the using the WSA formula with an extra parameter for the angular width (θb) from the nearest coronal hole. The present study puts in doubt in the usefulness of θb for these purposes.

Numerical simulation of transient mixed convection of water–Cu nanofluid in a square cavity with multiple rotating cylinders having harmonic motion

Mixed convection in a lid-driven square cavity with different walls temperature in the existence of four rotating cylinders having harmonic motion is simulated numerically for various parameters such as the solid volume fraction (0 ≤ ϕ ≤ 0.03), Richardson number (0.1 ≤ Ri ≤ 10) and type of motion for each cylinder. Cu–water nanofluids are considered as fluid inside the enclosure. A comparison of full rotation and harmonic rotation in steady and transient cases was made to get a better understanding of the effect of harmonic rotation. The consequences of this study are obtainable in terms of average and local Nusselt numbers, isotherm contours, streamlines contours, velocity profiles, PEC, and entropy generation profiles. Obtained results show that the heat transfer is dependent on the angular velocity of the cylinder, type of rotation, and the nanoparticle concentration. Adding nanoparticles causes to improve the heat transfer rate. However, the effect of the nanofluids on geometry has decreased for the PEC, except for Ri = 1 and a few particular cases. Also, according to the Nusselt number graphs, we can tell that the harmonic motion in this study did not have a considerable effect on the heat transfer rate.

Farming system effects on biologically mediated plant–soil feedbacks

AbstractCropping system characteristics such as tillage intensity, crop identity, crop-livestock integration and the application of off-farm synthetic inputs influence weed abundance, plant community composition and crop-weed competition. The resulting plant community, in turn, has species-specific effects on soil microbial communities which can impact the growth and competitive ability of subsequent plants, completing a plant–soil feedback (PSF) loop. Farming systems that minimize the negative impacts of PSFs on subsequent crop growth can increase the sustainability of the farming enterprise. This study sought to assess the individual and combined impact of the cropping system (certified organic-grazed, certified organic till and conventional no-till) and crop sequence [pairwise rotations with safflower (Carthamus tinctorius), yellow sweet clover (Melilotus officinalis) and winter wheat (Triticum aestivum)] on the PSF magnitude and direction. All cropping systems followed the same 5-year rotation and had completed one full rotation before soil was sampled. In a greenhouse setting, a sterile soil mix was inoculated with field soil collected from all systems and three crops. The PSF study consisted of two stages (conditioning and response phases) that mimicked the rotation stages occurring in the field. PSFs were calculated by comparing the biomass of the response phase plants grown in inoculated and uninoculated soils. The farm management system affected PSFs, inferring that tillage reduction can encourage more positive PSFs. Crop sequence did not affect PSF but interacted strongly with the farm system. As such, the effects of the farming system on PSFs are best illustrated when taken into account with the identity of the previous and current crops of a cropping sequence.

Limited view cone-beam x-ray luminescence tomography based on depth compensation and group sparsity prior.

.Significance: As a promising hybrid imaging technique with x-ray excitable nanophosphors, cone-beam x-ray luminescence computed tomography (CB-XLCT) has been proposed for in-depth biological imaging applications. In situations in which the full rotation of the imaging object (or x-ray source) is inapplicable, the x-ray excitation is limited by geometry, or a lower x-ray excitation dose is mandatory, limited view CB-XLCT reconstruction would be essential. However, this will result in severe ill-posedness and poor image quality.Aim: The aim is to develop a limited view CB-XLCT imaging strategy to reduce the scanning span and a corresponding reconstruction method to achieve robust imaging performance.Approach: In this study, a group sparsity-based reconstruction method is proposed with the consideration that nanophosphors usually cluster in certain regions, such as tumors or major organs such as the liver. In addition, depth compensation (DC) is adopted to avoid the depth inconsistency caused by a limited view strategy.Results: Experiments using numerical simulations and physical phantoms with different edge-to-edge distances were carried out to illustrate the validity of the proposed method. The reconstruction results showed that the proposed method outperforms conventional methods in terms of localization accuracy, target shape, image contrast, and spatial resolution with two perpendicular projections.Conclusions: A limited view CB-XLCT imaging strategy with two perpendicular projections and a reconstruction method based on DC and group sparsity, which is essential for fast CB-XLCT imaging and for some practical imaging applications, such as imaging-guided surgery, is proposed.

Rapid Cellular Perception of Gravitational Forces in Human Jurkat T Cells and Transduction into Gene Expression Regulation.

Cellular processes are influenced in many ways by changes in gravitational force. In previous studies, we were able to demonstrate, in various cellular systems and research platforms that reactions and adaptation processes occur very rapidly after the onset of altered gravity. In this study we systematically compared differentially expressed gene transcript clusters (TCs) in human Jurkat T cells in microgravity provided by a suborbital ballistic rocket with vector-averaged gravity (vag) provided by a 2D clinostat. Additionally, we included 9× g centrifuge experiments and rigorous controls for excluding other factors of influence than gravity. We found that 11 TCs were significantly altered in 5 min of flight-induced and vector-averaged gravity. Among the annotated clusters were G3BP1, KPNB1, NUDT3, SFT2D2, and POMK. Our results revealed that less than 1% of all examined TCs show the same response in vag and flight-induced microgravity, while 38% of differentially regulated TCs identified during the hypergravity phase of the suborbital ballistic rocket flight could be verified with a 9× g ground centrifuge. In the 2D clinostat system, doing one full rotation per second, vector effects of the gravitational force are only nullified if the sensing mechanism requires 1 s or longer. Due to the fact that vag with an integration period of 1 s was not able to reproduce the results obtained in flight-induced microgravity, we conclude that the initial trigger of gene expression response to microgravity requires less than 1 s reaction time. Additionally, we discovered extensive gene expression differences caused by simple handling of the cell suspension in control experiments, which underlines the need for rigorous standardization regarding mechanical forces during cell culture experiments in general.

Photoresponsive N,N′-disubstituted indigo derivatives

The synthesis and a comprehensive characterization of the excited state properties of five N,N′-substituted indigo (Ind) derivatives (acetyl-, benzoyl-, methoxybenzoyl-, nitrobenzoyl- and chlorobenzoyl-) was undertaken in various solvents and temperatures. In the excited state, rotation around the central double bond was found with N,N′-diacetylindigo (DAI) and N,N′-dibenzoilindigo (DBI) derivatives. Both DAI and DBI acyl derivatives show rotation in the excited state around the central C–C bond, leading to a conical intersection (CI). Steric hindrance prevents DBI from accomplishing full rotation (which consequently does not fully isomerize) with two conformers being experimentally found from both fs-transient absorption and time-resolved emission measurements. For DAI, the fluorescence decays are single exponential (varying from 2790 ps in 2MeTHF to 7520 ps in MCH), while fs-TA indicates the presence of two species, with lifetimes, in 2MeTHF, of 33 ps and 2790 ps. All the acyl derivatives show blue shifted absorption and emission from the parent indigo dye due to stabilization of the π HOMO orbital in the S1 π*←π transition by delocalization to the acyl carbonyl. The extent of blue shift among the different acyl derivatives is found to depend on the geometric constraints imposed on the dihedral angle between indigo and the acyl group. With the DBI derivatives, interconversion between the two conformers in the excited state leads to rate constant values ranging from 1.3 × 1010 s−1 (in MeTHF) to 3.6 × 109 s−1 for the nitrobenzoyl-DBI derivative (in dioxane).

Design of rotating table control for acquiring an image in industrial gamma-ray CT prototype using Raspberry Pi 3B+ module

The rotating table on an industrial gamma-ray CT device is used to rotate the detector consisting of a line scanner and a gamma-ray source around the test object. The process of acquiring the image is done by rotating the detector and the source 360 degrees around the object, and at a certain angle, the object projection image is captured through the line scanner. A stepper motor is used to rotate the rotating table. The rotary motion of the stepper motor is controlled using the Raspberry Pi 3B+ control module which can be accessed remotely using the TCP/IP communication protocol. As an interface to control the motion of the rotating table, a software that is created using the python programming language is used. The gear ratio between the motor and the rotating table is 23 : 161 which takes 7 full rotations on the stepper motor to produce one full rotation on the rotating table. Based on the test results, 25200 pulses input is needed to rotate the rotating table 360 degrees, while one pulse is able to move the rotating table by 0.0143 degrees.

Human motion tracking under indoor and outdoor surveillance system

This paper gives an overview of the various potential applications involved in human motion tracking. Also, a review of some relevant algorithms in this area are summarised based on three main components: the human target extraction, the features extraction, and the motion model. In addition, a proposed generative and discriminative human tracking method is presented. This proposed method is based on the hybridisation of Kalman filter (KF) and the support vector machines (SVMs). Numerous experiments illustrate the effectiveness of the proposed method against several state of the art trackers. These experiments are applied on several real world image sequences with various challenges that make the tracker vulnerable which are: partial and full occlusions, illumination changes, scale variation, out-of-plane, rotation, motion blur, low resolution, deformation, fast motion and background clutter.

Optimized stereotactic volumetric modulated arc therapy as an alternative to brachytherapy for vaginal cuff boost. A dosimetric study

We evaluate the role of stereotactic body radiotherapy using volumetric modulated arc therapy (VMAT) technique as an alternative to high-dose rate brachytherapy (HDR-BT) in the treatment of vaginal cuff in postoperative endometrial cancer. CT scans of 8 patients were used in this study. The clinical target volume (CTV) was defined as the 0.5 cm tissue around the applicator (then subtracting the applicator). Total dose was 30Gy delivered in 5 fractions. In HDR-BT, dose was prescribed at a distance of 0.5 cm from the surface applicator. For VMAT irradiation, a planning target volume (PTV) was obtained from CTV by an expansion of 3 mm. Two VMAT plans were generated using a full arc rotation. The first plan was optimized with an anatomy-based optimization module (PO-VMAT) using a 1mm multileaf collimator beam margin to enhance dose heterogeneity and dose fallout outside the target. The second plan was generated with a full-inverse planning module (FI-VMAT). Conformity (CI100, CI50, CI25), gradient (GI) indexes, and integral doses were calculated. To account for various dose heterogeneity distributions we calculated the equivalent uniform dose (EUD) using the Niemerko model. A Kruskal-Wallis analysis of variance followed by Dunn’s-type multiple comparisons was performed. Dose distributions were more heterogeneous with HDR-BT: Dmean was 144.2% of prescription dose for CTV in HDR-BT and 118.5 and 108.6% for PTV in PO-VMAT and FI-VMAT, respectively. The mean values of EUD for CTV were 136.9%, 130.0 %, and 111.0% of prescription dose in HDR-BT, PO-VMAT, and FI-VMAT plans, respectively. GI indexes were 2.81, 3.41, and 4.14 for HDR-BT, PO-VMAT, and FI-VMAT, respectively. Near-maximal doses (D0.1cc) for rectum and bladder were significantly higher in HDR-BT plans compared to PO-VMAT and FI-VMAT plans (rectum: 131.2% vs112.8% vs 112.0%, respectively; bladder: 129.2% vs 108.7%, and 109.8%, respectively). PO-VMAT plans were able to mimic the HDR-BT dose distribution, showing a successful capability of highly conformal dose distribution, EUD values similar to HDR-BT, and steep dose-gradient outside PTV, then providing a reasonable alternative to brachytherapy.

Comparative analysis of the energies of needle bar mechanisms of the sewing machines

Introduction: Sewing machines a set of mechanisms that work together, of which the most dynamic mechanism is the one that drives the needle. Stitch quality, the stitch strength and the productivity of the sewing machine largely depend on the work of the needle bar mechanism. The main task during the study dynamics of the sewing machine mechanisms is to determine the energy balance. Purpose: The aim is to determine the total energy consumed by the mechanisms per one full rotation of the main shaft of each machine; the share of energy consumed by each unit of the needle bar mechanism for one turnover; the ratio of the energy of each of the links of the mechanism both during the working motion and during the free motion of the needle. Materials and Methods: The object of the study is the energies of the needle bar mechanisms of the sewing machines Juki DDL5550 and Textima 8332. An energy distribution analysis was performed during the working process and the free stroke of the sewing needle. The energies of the mechanisms of the two sewing machines were compared. Results: Were calculated maximum energy values are as follows: of the rocker: for Juki DDL5530 Ek = 2,8051 kg.m2/s2 and for Textima 8332 Ek = 1,3864 kg.m2/s2; of the executive links - the needle bars: for Juki DDL5530 Ek = 5,9507 kg.m2/s2 and for Textima 8332 Ek = 4,3696 kg.m2/s2; general energy of needle bar mechanism: for Juki DDL5530 Ek = 8,7487 kg.m2/s2 and for Textima 8332 Ek = 5,7416 kg.m2/s2. Conclusion: The comparative analysis reveals that the energy consumption of the needle bar mechanism of Juki DDL5530 is significantly higher. Consequently, the energy consumption indicator of the Textima 8332, which is directly driven without a clamp, is more efficient.

Characterization and Performance Evaluation of the First-Proton Therapy Facility in India.

Purpose:The purpose of this study is to evaluate the performance characteristic of volumetric image-guided dedicated-nozzle pencil beam-scanning proton therapy (PT) system.Materials and Methods:PT system was characterized for electromechanical, image quality, and registration accuracy. Proton beam of 70.2–226.2 MeV was characterized for short- and long-term reproducibility in integrated depth dose; spot profile characteristics at different air gap and gantry angle; positioning accuracy of single and pattern of spot; dose linearity, reproducibility and consistency. All measurements were carried out using various X-ray and proton-beam specific detectors following standard protocols.Results:All electro-mechanical, imaging, and safety parameters performed well within the specified tolerance limit. The image registration errors along three translation and three rotational axes were ≤0.5 mm and ≤0.2° for both point-based and intensity-based auto-registration. Distal range (R90) and distal dose fall-off (DDF) of 70.2–226.2 MeV proton beams were within 1 mm of calculated values based on the international commission on radiation units and measurements 49 and 0.0156× R90, respectively. The R90 and DDF were reproducible within a standard deviation of 0.05 g/cm2 during the first 8 months. Dose were linear from 18.5 (0.011 MU/spot) to 8405 (5 MU/spot) MU, reproducible within 0.5% in 5 consecutive days and consistent within 0.8% for full rotation. The cGy/MU for 70.2–226.2MeV was consistent within 0.5%. In-air X(Y) spot-sigma at isocenter varies from 2.96 (3.00) mm to 6.68 (6.52) mm for 70.2–226.2 MeV. Maximum variation of spot-sigma with air-gap of ±20 cm was ±0.36 mm (5.28%) and ±0.82 mm (±12.5%) along X- and Y-direction and 3.56% for full rotation. Relative spot positions were accurate within ±0.6 mm. The planned and delivered spot pattern of known complex geometry agreed with (γ%≤1) for 1% @ 1 mm >98% for representative five-proton energies at four gantry angle.Conclusion:The PT-system performed well within the expected accuracy level and consistent over a period of 8 months. The methodology and data presented here may help upcoming modern PT center during their crucial phase of commissioning.

Metod za samokalibraciju magnetno-rezistivnog senzora ugaone pozicije u servo sistemima

Magneto-resistive and Hall angular position sensors are frequently used in servo systems, due to their reliability, longevity, and tolerance to environmental conditions. In this paper, a measurement error compensation is integrated into the servo system control structure. The compensation consists of two steps: a linear compensation of the magnetic field vector measurement error, and harmonic compensation of the angular position measurement error. The selfcalibration method uses data collected during rotation with maximal speed to identify parameters of the measurement process model. Identification is executed periodically, each time when the shaft makes a full rotation. The least squares method is utilized for identification of the linear compensation parameters, while the average rotational speed is used as an internal reference for the harmonic compensation parameters identification. The method, together with a fast convergence, increases the measurement accuracy by an order of magnitude. Experimentally achieved measurement error is below 0.7°, with residual variance below 0.05°, comparable with sensor differentiability.

A rationale of broach-plow’s parameters of the ridge-stepped ploughing of slopes

The aim of this study was to develop an improved technology for ridge-stepped ploughing of slopes and plow, which protects the soil from water erosion, improves the accumulation and preservation of soil moisture. The paper proposes an effective method for ridge-stepped ploughing of slopes, including the alternation of layer’s incomplete rotation with its full rotation within its furrow by 1800 in combination with the band subsoil loosening. A technological model of a ridge-stepped ploughing with simultaneous subarable strip loosening was developed. The design of the developed plow for ridge-stepped ploughing is highlighted. During the study the followings were theoretically and experimentally established: with a longitudinal distance between the hulls of 50 cm, the required qualitative incomplete turnover of the layers with the lowest energy costs is provided with the following plow’s parameters of the odd hulls: plow length is 75 cm, plow width is 25 cm, stabilizing plate height is 15 cm, and the minimum distance from the ploughshare toe to the stabilizing plate is 25 cm.

Characterization of Rotating Objects With Tomographic Reconstruction of Multiaspect Scattered Signals

The backscattered signals of objects under spinning motion or with rotating parts provide very rich information that can be used for classification tasks, parameter extraction, etc. Obtaining such information from noncooperative objects with an unknown target-aspect is often a complicated task with a monostatic configuration. A multistatic radar on the other hand, can exploit the spatial diversity to extract the information from the time–frequency representations obtained from multiple aspect-angles. In this paper, we propose a tomographic approach for characterizing spinning objects in terms of their shape, size, and rotation parameters using a narrow-band multistatic radar. A two-dimensional image is reconstructed after a full rotation period using tomographic methods that allows not only to estimate the shape of the target but also the rotation parameters and the dimensions of the object. This is done very efficiently by combining the tomographic images from different aspect-angles on the transformed log-polar space, instead of the time–frequency representations. Simulations and measurements were conducted for the proof of concept. The measurement results with a simple target and a continuous wave K-band radar show errors below 3 $^{\circ }$ for the orientation estimation and below 5% for the estimation of the object's diameter.

Computational method to determine the pitch length in cholesteric liquid crystals

Cholesteric liquid crystals are consisted of nematic layers, with a small rotation of the director as we pass from one to the other. This rotation produces a helical structure and the distance to perform one full rotation of the director is known as the pitch length. The pitch length characterizes the cholesteric mesophase and, for this reason, in the present article, we propose a computational method to determinate this parameter with high precision. We use the texture of the cholesteric phases obtained via polarizing light microscopy and an Object Pascal language to write our program.

Dynamic rotational alteration in positional relationship of neurovascular structures and distal biceps tendon insertion: a cadaveric study

ObjectivesThis study analysed the change in positional relationship of major neurovascular (NV) structures with the distal biceps tendon (DBT) insertion with dynamic rotation.MethodsFresh frozen cadaveric upper extremities (n=10) were dissected to expose DBT and five major NV structures (ulnar artery (UA), radial artery (RA), median nerve (MN), superficial radial nerve (SRN) and posterior interosseous nerve (PIN)). The distance between each NV structure and the DBT insertion was measured with the elbow in (a) full supination (90°), (b) neutral rotation (0°) and (c) full pronation (80°). Statistical analysis was performed to determine significant changes in rotational NV excursion in relation to DBT insertion.ResultsRA and UA were in contact with DBT just distal to the bifurcation of brachial artery. RA was closest to DBT insertion in supination (5 mm), and MN (7 mm) and UA (9 mm) were further away. UA was in close proximity in neutral (4 mm) and pronated (6 mm) positions. UA moved significantly closer to DBT insertion when rotated from supination to neutral (p<0.0001) and pronated (p<0.0018) positions. RA and MN moved significantly further from DBT in these positions (p<0.05). SRN and PIN were the farthest structures from DBT insertion in supination and neutral positions.ConclusionNV structures in the cubital fossa are in close proximity to DBT and its tuberosity insertion and dynamic rotation significantly changes their positional relation with DBT insertion.Level of evidenceBasic science study

CONCENTRATION OF NITRATE NITROGEN IN THE SOIL AND PRODUCTIVITY OF CROPS WHEN LONG-TERM MINIMIZING OF TILLAGE ACCORDING TO VARIOUS FORECROPS

In a multifactor stationary field experiment on the area of the Elitnoye Holding in the Novosibirsk region (central forest-steppe subzone) in 2002-2018 the seasonal dynamics of nitrate nitrogen in the fields of four full grain-steam crop rotation by steam and grain predecessors against an extensive background (without chemical means) in four versions of the main mechanical treatment of leached black soil was investigated. Along with this, the productivity of grain crops was studied with long-term minimization of the main tillage on extensive and intensive backgrounds. The authors found out that in the central forest-steppe of the Ob river region before sowing grain crops according to the various methods of steam preparation most of all in the meter layer of nitrate soil was found in black steam with plowing (150 kg / ha) and less in variants with soil-protective treatments (132-141 kg / ha ). The lowest level of this element in the soil (124 kg / ha) in spring was noted by the early minimum steam. Before sowing the second wheat after steam, the nitrate nitrogen content in the meter soil layer for plowing (79 kg / ha) was slightly higher than in the options with soil treatment (61-64 kg / ha). In the final field of crop rotation, regardless of the studied soil cultivation systems, the minimum initial amount of nitrogen (56-57 kg / ha) was noted. By the end of the growing season of crops, the nitrate content in the soil was sharply reduced. Before harvesting wheat by steam, the nitrogen content in the upper meter profile was 41-55 kg / ha, for grain precursors even less - 27-33 kg / ha. The steam yield of grain crops on extensive and intensive backgrounds was 3.09-3.21 and 3.96-4.02 t / ha, respectively, and practically did not depend on the methods of its preparation. On repeated sowing the wheat yield in comparison with an extensive background in plowing (1.26-1.79 t / ha) was significantly higher than in the studied options for minimizing the main tillage (1.02-1.55 t / ha). When optimizing the mineral nutrition of plants and the phytosanitary situation of crops, wheat productivity by grain predecessors in crop rotation fields increased 2.0-2.9 times without significant differences in soil treatment options.

Controlling collective rotational patterns of magnetic rotors

Magnetic actuation is widely used in engineering specific forms of controlled motion in microfluidic applications. A challenge, however, is how to extract different desired responses from different components in the system using the same external magnetic drive. Using experiments, simulations, and theoretical arguments, we present emergent rotational patterns in an array of identical magnetic rotors under an uniform, oscillating magnetic field. By changing the relative strength of the external field strength versus the dipolar interactions between the rotors, different collective modes are selected by the rotors. When the dipole interaction is dominant the rotors swing upwards or downwards in alternating stripes, reflecting the spin-ice symmetry of the static configuration. For larger spacings, when the external field dominates over the dipolar interactions, the rotors undergo full rotations, with different quarters of the array turning in different directions. Our work sheds light on how collective behaviour can be engineered in magnetic systems.