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The work is devoted to mathematical modeling of a DC motor rotation speed control system based on the use of a PI controller. DC motors are widely used in industry for driving cyclical mechanisms where high speed response, high starting torque, linear control are required. The main methods for controlling the required characteristics of the speed of rotation of a DC motor with independent excitation are to control the parameters of the armature and excitation windings fed from different sources. The PI controller is widely used in programmable logic controllers due to the simplicity and clarity of the mathematical apparatus. The proposed mathematical model of the PI controller is based on the choice of optimal parameters that ensure that the actual speed is kept close to the set one. The optimum PI controller coefficients KP and KI have been determined to give the best result for a constant speed. The results of computer simulation in MatLab are compared with the results of simulation on a laboratory setup. The data are obtained when using the PI controller for the steady-state error and transient time look preferable to the simulation model with voltage regulation. The developed mathematical model shows the following main results: acceleration time < 0,3 s; transient process time < 0,5 s; overshoot does not exceed 0,5 %; the steady-state error does not exceed 0,1 %. As a result of the study, a mathematical model is developed and the operation of a DC motor with a PI controller is analyzed, which makes it possible to almost completely eliminate forced oscillations and a steady-state error. The advantage of the proposed method of using the PI controller is noted as a more familiar and easy-to-use control element when implemented in existing control systems without any special changes.

Abstract The CUPID-Mo experiment to search for 0 $$\nu \beta \beta $$ ν β β decay in $$^{100}$$ 100 Mo has been recently completed after about 1.5 years of operation at Laboratoire Souterrain de Modane (France). It served as a demonstrator for CUPID, a next generation 0 $$\nu \beta \beta $$ ν β β decay experiment. CUPID-Mo was comprised of 20 enriched $$\hbox {Li}_{{2}}$$ Li 2 $$^{100}$$ 100 $$\hbox {MoO}_4$$ MoO 4 scintillating calorimeters, each with a mass of $$\sim 0.2$$ ∼ 0.2 kg, operated at $$\sim 20$$ ∼ 20 mK. We present here the final analysis with the full exposure of CUPID-Mo ( $$^{100}$$ 100 Mo exposure of 1.47 $$\hbox {kg} \times \hbox {year}$$ kg × year ) used to search for lepton number violation via 0 $$\nu \beta \beta $$ ν β β decay. We report on various analysis improvements since the previous result on a subset of data, reprocessing all data with these new techniques. We observe zero events in the region of interest and set a new limit on the $$^{100}$$ 100 Mo 0 $$\nu \beta \beta $$ ν β β decay half-life of $$T_{1/2}^{0\nu }$$ T 1 / 2 0 ν $$> {1.8}\times 10^{24}$$ > 1.8 × 10 24 year (stat. + syst.) at 90% CI. Under the light Majorana neutrino exchange mechanism this corresponds to an effective Majorana neutrino mass of $$\left$$ m β β $$

Catheter ablation occupies the first place in the treatment of atrial macro reentry arrhythmias. The main controllable parameters in ablations are energy, duration of exposure and use of catheter tip cooling. With traditional ablation techniques, there is a high risk of insufficient tissue damage due to electrode instability. Regarding the issue of stability, a new technique was proposed – reducing the application time with increasing the energy. The aim of this work was to compare the results of radiofrequency catheter ablation (RFA) using an 8 mm uncooled electrode to a 4 mm cooled electrode and a 4 mm cooled electrode with increased energy. Materials and methods. The work is based on a retrospective analysis of the results of catheter ablations in patients with atrial flutter. Patients were divided into 3 groups depending on the parameters of the used radio frequency energy and the type of ablation electrode. Results. It was found that in the group with increased energy, there were the shortest time from the start of RFA to the achievement of success criteria and the lowest radiation exposure. The obtained differences were statistically significant in comparison with two groups of patients who underwent traditional methods. Such differences were associated both with a reduction in the time of the application itself due to the use of high energy as well as the need to apply a smaller number of applications owing to a lower probability of the electrode displacement from the target area. Conclusions. The use of a high-energy protocol allows to success criteria for cavo-tricuspid isthmus ablation more quickly compared to traditional techniques (by 30 % and 22 %, respectively) with less radiation exposure (by 27 % and 24 %, respectively). The use of the high-energy protocol does not lead to an increase in the frequency of complications and can be considered safe for clinical use.

Atrial macro reentry tachycardias are the most common tachyarrhythmias in the structure of cardiac arrhythmias in the elderly. Catheter ablations are the gold standard for the treatment of atrial macro reentry arrhythmias, but in the elderly group, the risks of complex ablations often outweigh the benefits. Aim: to determine the optimal volume of catheter ablation in atrial tachyarrhythmia using an implanted pacemaker in elderly patients. Materials and methods. The work is based on a retrospective analysis of the results of surgical treatment of (n = 45) elderly patients (75–90 years) with atrial macro reentry tachycardia, who were previously identified as an artificial pacemaker at the National M. Amosov Institute of Cardiovascular Surgery Affiliated to National Academy of Medical Sciences of Ukraine. Patients were divided into 3 groups depending on the response of the reentry tachycardia to electrical pacing (assessed by the difference between postpacing interval (PPI) and tachycardia cycle lens (CL): group І – PPI-CL 20–40 ms; group ІІ – PPI–CL 20–40 ms; group ІІІ – PPI-CL 60 ms and more. Results. In the group I (n = 20) in 100 % of the patients isthmus-dependent reentry tachyarrhythmia was diagnosed and cava-tricuspid isthmus was ablated. In the group ІІ (n = 12) 4 (33 %) patients were diagnosed with reentry tachycardia around the right pulmonary veins, in 8 (67 %) patients – reentrant tachycardia around the mitral valve. In the group ІІІ (n = 13) in 8 (62 %) patients macro reentry around the mitral valve was found, in 3 (23 %) – reentry around the left pulmonary veins, in another 2 (15 %) of the patients – reentry of the left atrial roof. Conclusions. Non-invasive electrophysiological study with pacemaker can be an effective way to study atrial macro reentry tachyarrhythmias. Electrophysiological PPI-SI criteria less than 20 ms can be used as an additional diagnostic criterion for the selection of patients for surgical treatment. Catheter ablation is recommended for elderly patients when the reentry circle is located in the right atrium.

Atrial tachyarrhythmias are becoming more common in the population. The prevalence increases with age. Often, these arrhythmias lead to disability and reduced life expectancy (indirectly through strokes). Drug therapy of atrial tachyarrhythmias reduces symptoms but does not completely resolve issue of treatment. In this regard, surgical treatment (catheter ablation) is preferable. One of the methods of catheter ablation is ablation using radio frequency energy. The key parameters of radiofrequency catheter ablation are the energy delivered to the endocardium and the time of this energy delivery. According to the traditional method, it is customary to use energy of 30 Watts for 30 s at one point. This technique has a disadvantage – in 30 s the electrode can be displaced, and the application of energy has to be repeated. A new strategy was proposed – reducing the application time by increasing the energy to respond to the challenge of high probability of electrode displacement. The aim of this work was to determine the effectiveness of the рhigh-power short-duration protocol. Materials and methods. To carry out this work, we analyzed the surgical treatment of atrial fibrillation with the help of radiofrequency catheter ablation – isolation of the pulmonary veins. In patient group 1, ablation was performed using an irrigated ablation electrode with an energy of 30 Watts and an application time of 30 s, in group 2 – using the irrigated electrode with the energy of 70 Watts and the application time of 5 s. Ablations were performed under the control of radiography and electroanatomical mapping system. Full electrical isolation of the four pulmonary veins with confirmation of the entrance and exit block were considered as the criteria of efficiency. Results. When comparing the groups by the number of required application cycles during the procedure needed to achieve the clinical effect and time to the first recurrence in all positions of the electrode, group 2 showed a lower number of applications and shorter time to the first recurrence. Reducing the time to pulmonary vein isolation, the number of relapses and restarting the control time, as well as shortening the time spent on the need to rebuild the electroanatomical map have resulted in a significant decrease in the duration of the radiofrequency ablation procedure. Conclusions. The work has shown that the use of the new protocol is more effective and allows to achieve the criteria of success faster than the traditional technique; the number of the procedure complications was not higher compared to traditional methods. When using the ablation protocol with higher energy, a lower incidence of atrial fibrillation recurrence was recorded.

Проведення емпіричного дослідження різного впливу міжнародної торгівлі в періоди стабільної світової економіки, кризових явищ та посткризового відновлення вможливлює формування узагальнених засад зовнішньоторговельної політики, спрямованої на підвищення темпів економічного зростання. Метою роботи є визначення впливу факторів міжнародної торгівлі на економічне зростання за кожним із періодів економічного стану та обґрунтування гіпотези щодо доцільності адаптації міжнародної торгівлі до економічної ситуації в країні. У роботі використано інструмент нечітких нейронних мереж щодо просторових даних 82 країн світу за часовими інтервалами стабільності, кризи та посткризового відновлення, що дозволило знайти раціональний підхід до формування орієнтирів міжнародної торгівлі за різних макроекономічних умов. Результати дослідження показали, що в періоди стабільної економіки максимізація реально досяжних темпів економічного зростання (близько 10-20%) відбувається при середніх і порівняно однакових рівнях експорту та імпорту (від 30% до 60%). При цьому потенційний сплеск темпів економічного зростання може буде досягнутий шляхом скорочення рівня експорту при збереженні середнього рівня імпорту. Під час кризових явищ найбільш стабільними є країни, що обмежили імпорт і зберегли середній рівень експорту своєї продукції, а потенційні можливості нарощення темпів економічного зростання вбачаються в підвищенні імпорту до докризового рівня. У часи посткризового відновлення найбільші потенційні темпи економічного зростання досягаються при максимально можливому нарощенні експорту та скороченні рівня імпорту. Констатовано, що експорт високотехнологічної продукції є впливовим фактором економічного зростання. Проте його рівень доцільно адаптувати до макроекономічних умов і структури міжнародної торгівлі, орієнтуючись на теорію меркантилізму.

Measured binary quasifission mass spectra in reactions with actinide nuclides show a large peak in yield near the doubly-magic 208Pb, generally attributed to enhanced binding energy causing a valley in the potential energy surface, which attracts quasifission trajectories. Measurements of binary quasifission mass spectra and cross-sections have been made for reactions of 50Ti with actinide nuclides from 232Th to 249Cf. Cross-sections have also been deduced for sequential fission (a projectile-like nucleus and two fragments from fission of the complementary target-like nucleus). Binary cross-sections fall from 70% of calculated capture cross-sections for 232Th to only 40% for 249Cf, with a compensating increase in sequential fission cross-sections. The data are consistent with the peak in yield near 208Pb originating largely from sequential fission of heavier fragments produced in more mass-asymmetric primary quasifission events. These are increasingly suppressed as the heavy quasifission fragment mass increases above 208Pb. The important role of sequential fission calls for re-interpretation of quasifission observables and dynamics in superheavy element synthesis reactions.

This paper presents the results of studies on the examination of rural areas in the regions of the Siberian Federal District (SFD) regarding the organization and expansion of organic agricultural production. For the socio-economic characterization and compilation of the rating potential of the SFD subjects, demographic, infrastructure, and territorial groups of factors were identified. The main competitive advantages of production and implementation of organic products were identified for each region. The rating compiled by the authors identifies the Novosibirsk region as the most promising for the development of various forms of organic agriculture. Krasnoyarsk, Irkutsk, and Tomsk regions also have high potential. The Republic of Altai and the Omsk region can be considered as regions of medium prospects due to limitations imposed by the weak development of some of the factors considered. The Republics of Tuva and Khakassia, as well as Altai and Kemerovo regions, are limitedly suitable for the development of the organic sector. A clear definition of the priorities of agricultural producers, the choice of a suitable strategy, and the presence of state support at all stages of the organization of organic production will be a necessary condition for the successful development of the sector.

It is noted in the work that the increase in the efficiency of agricultural production in our time is not possible without reducing energy costs. At the same time, the technical means of mechanization of the tillage process have a high material consumption, which leads to an increase in energy consumption, indicating energy and environmental problems. In an effort to improve the quality of soil preparation, expand the functionality of the unit, reduce energy consumption, simplify design and import substitution, the use of known tillage tools has been studied and analyzed. As a result, on the basis of exploratory research, a modernized tillage unit has been developed. The new elements of which are that a chopper module is mounted behind the disk module, consisting of staggered chopper rollers in two rows. The modernized tillage unit considered in the article, developed on the basis of KubGAU, improves the quality indicators of soil cultivation, on which the effective accumulation and consumption of soil moisture depends, reduces energy consumption by increasing the functionality of the unit.

The conducted research is devoted to the analysis of the wear resistance of materials used in reinforcing coatings of working bodies of agricultural machines subjected to friction under abrasive action in soil conditions. The aim of the study was to determine the degree of wear of the hardened teeth of the disc under the load of their impact on the soil in real operating conditions. The disk of a toothed harrow, which is a hardened working body of agricultural machinery, was used as an object of research. The individual teeth of this disc were the test samples. To increase the wear resistance of the teeth, a variety of reinforcing coatings were applied. The results of the study made it possible to comparatively evaluate the effectiveness of various reinforcing coatings and identify their effect on the wear resistance of the teeth of the disc. This study provides important data for further improvement of materials and technologies in agricultural engineering in order to increase the durability and efficiency of working bodies.

One of the characteristic properties of organofluorine compounds is their low surface energy. In this regard, surfactants containing perfluoroalkyl groups, as a rule, are much more effective than their nonfluorinated analogues. The unique character of fluorinated surfactants is also determined by their pronounced oleophobic properties. Surfaces treated with fluorinated surfactants are not only water-repellent, as in the case of their hydrocarbon analogues, but also benzo- and oil-repellent. Fluorotensides are highly resistant to oxidants and aggressive substances (acids, alkalis, chlorine, etc.). They also have high temperature resistance, withstand oxygen shock, have a solidification temperature of up to -160 °C, do not change properties at a dose rate of up to 108 rad. The applications of surfactants are extremely diverse. One of the methods of increasing the wear resistance of friction pairs is the method of surface treatment of friction pairs with fluorotensides. Fluorotensides are multicomponent systems that include organofluorine surfactants in various solvents and regulatory additives. In Russia, brands of fluorotensides have been created that surpass foreign samples in many respects, which has significantly expanded the scope of their application.

The material of the scientific article represents a separate stage of research on a topical topic dedicated to increasing the economic efficiency of feed mills. The solution to this problem significantly depends on the technical condition and quality of the work process carried out by technological equipment. Based on an analysis of the state of the issue on the topic under consideration, it was established that the most important and energy-intensive operation of the feed preparation process is grinding, performed in feed crushers. A study of the operating conditions of hammer crushers revealed the least reliable working element - the grinding rotor, the technical condition of which is determined by wear of the support bearings, increased vibration and imbalance. In order to substantiate the method of automated diagnostics of rotor malfunctions during operation, determine the accuracy of manufacturing crushers at factories, and assess the quality of service and repair at service enterprises, a scheme for static and dynamic loading of the rotor has been developed.

The paper examines the issues of providing electrical energy to tractors operating on electric traction. Problems associated with the lack of infrastructure necessary for charging and recharging traction batteries are described. The rationale for the operation of electric tractors in agriculture is given. The article provides an overview of the available types of charging stations, their advantages and disadvantages, as well as some technical characteristics. The development and use of mobile charging stations for charging and recharging traction batteries of electric tractors directly in the field is substantiated. The main results provide information about the designed mobile charging station. The article contains a description of the design and composition of a mobile charging station, through which traction batteries are charged directly in the field. The rationale for choosing the type of charging station and the method of supplying it with electrical energy is presented. Particular attention is paid to the rational choice of storage batteries that will be located in the charging station. An assessment of the used rechargeable batteries is carried out, their main advantages and disadvantages are given, as well as the type of batteries chosen for use is justified.

The article considers the prospect of using technologies for processing low-quality, damaged wood and wood waste by grinding in the interests of energy use. The data on the dynamics of the increase in the areas of plantations with impaired and lost stability, the causes of these phenomena on the example of the Krasnoyarsk Territory are presented. Various options for the disposal and use of wood waste, including from logging activities, are described. The main advantages and possible disadvantages of the introduction of technological processes for grinding wood raw materials are also given. The analysis of trends in the production of wood pellets in Russia and the world is carried out. Attention is paid to minimizing the impact of existing wood processing technologies on environmental safety and improving the efficiency of business activities based on the involvement of wood waste in the production process as raw materials for the fuel and energy sector, as well as obtaining new, highly liquid products and materials. The materials of the work can be used in making decisions related to the involvement in industrial production or disposal of low-quality, damaged wood and wood waste.

Individual housing construction in the Krasnoyarsk Territory is actively developing. Rising housing prices in multi-storey buildings, increasing building density, and socio-demographic factors are increasing the popularity of individual construction. Technologies for such construction imply the widespread use of available local building materials, in particular wood. During the study, the designs of private houses in the settlement - the regional center of the Krasnoyarsk Territory - were analyzed. It was found that 90% of the sample examined were houses built from timber. Using simulation modeling methods, the actual thermal resistance of the enclosing structure made of timber with a cross-section of 0.15×0.15 m was determined. The calculated value was compared with the standard resistance indicator of the enclosing structure, taking into account energy saving standards. The Elcut solid modeling system was used in the work. The required heat flow power to maintain stationary heat transfer conditions was determined. It has been established that the design enclosing structure does not provide the required thermal resistance taking into account energy saving standards. It is necessary to consider a multilayer enclosing structure and increase the design resistance by insulating the outer surface of the wall with heat-insulating materials.

The article proposes a method for calculating the static position of the machine body. The mathematical model of the running gear is given. The dependence of the position of the center of mass in height relative to the ground on the pre-tension forces, as well as the angular deviation of the longitudinal axis of the hull from the horizontal position, is shown. A control calculation was performed, the results of which are presented in the form of graphical dependencies. The numerical experiment was carried out on the example of a tracked vehicle of a light category with a rear drive wheel.

The relevance of the article is due to the need to replace petroleum diesel fuel with fuels obtained from alternative raw materials. Rapeseed oil is considered as an alternative motor fuel. The properties of petroleum diesel fuel and rapeseed oil are analyzed. The influence of these properties of fuels on the characteristics of their injection and spraying is investigated. The deterioration of the quality of the injection and spraying processes was noted when the engine was switched from petroleum diesel fuel to rapeseed oil. When replacing diesel fuel with rapeseed oil, a slight increase in the maximum injection pressure and the duration of fuel supply was noted. Other parameters of fuel injection and atomization processes practically did not change. To achieve the required performance indicators of the diesel engine, it is necessary to implement measures that improve the quality of the workflow. These measures include the regulation of the fuel injection advance angle, optimization of the geometry of the flow part of the nozzle sprayer, two-phase fuel supply. It is advisable to switch from rapeseed oil to mixed biofuels and optimize their composition.

The Majorana Demonstrator is searching for neutrinoless double-beta decay in 76Ge with two modular arrays of natural and 76Ge-enriched germanium detectors. It is located at the 4850' level of Sanford Underground Research Facility in Lead, South Dakota, USA, and its total mass of germanium detectors is 44.1 kg, of which 29.7 kg is enriched. The analysis of the first 26 kg-yr of data provides an unprecedented energy resolution of 0.13% in the region of interest at 2039 keV and a background level of 15.4 ±2.0 counts/(FWHM t yr). It establishes the lower limit of the half-life of neutrinoless double beta decay as 2.7 1025 yr in 76Ge at 90% CL. This analysis will be summarized here with an emphasis on the energy determination.

The half-life of 100Mo relatively to the 2ν2β decay to the ground state of 100Ru was measured as T1/2 = (6.99±0.15) × 1018 yr with the help of enriched in 100Mo lithium molybdate scintillating bolometers in the EDELWEISS-III low background set-up at the Modane underground laboratory. This is the most accurate value of the 2ν2β half-life of 100Mo.

The half-life of 100Mo relatively to the 2ν2β decay to the ground state of 100Ru was measured as T1/2 = (6.99±0.15) × 1018 yr with the help of enriched in 100Mo lithium molybdate scintillating bolometers in the EDELWEISS-III low background set-up at the Modane underground laboratory. This is the most accurate value of the 2ν2β half-life of 100Mo.

The Majorana Collaboration is operating an array of high-purity Ge detectors to search for the neutrinoless double-β decay of Ge76. The Majorana Demonstrator consists of 44.1 kg of Ge detectors (29.7 kg enriched to 88% in Ge76) split between two modules constructed from ultraclean materials. Both modules are contained in a low-background shield at the Sanford Underground Research Facility in Lead, South Dakota. We present updated results on the search for neutrinoless double-β decay in Ge76 with 26.0±0.5 kg yr of enriched exposure. With the Demonstrator's energy resolution of 2.53 keV FWHM at Qββ, which is the best among all neutrinoless double-β decay experiments, we observe one event in the region of interest with 0.65 events expected from the estimated background, resulting in a lower limit on the Ge76 neutrinoless double-β decay half-life of 2.7×1025 yr [90% confidence level (CL)] with a median sensitivity of 4.8×1025 yr (90% CL). Depending on the matrix elements used, a 90% CL upper limit on the effective Majorana neutrino mass in the range of 200-433 meV is obtained. The measured background in the configurations with full shielding and optimized grounding is 11.9±2.0 counts/(FWHM t yr).

The MAJORANA DEMONSTRATOR is an experiment constructed to search for neutrinoless double-beta decay in 76Ge and to demonstrate the feasibility to deploy a large-scale experiment in a phased and modular fashion. It consists of two modules of natural and 76Ge-enriched germanium detectors totalling 44.1 kg, operating at the 4850' level of the Sanford Underground Research Facility in Lead, South Dakota, USA. Commissioning of the experiment began in June 2015, followed by data production with the full detector array in August 2016. The ultra-low background and record energy resolution achieved by the MAJORANA DEMONSTRATOR enable a sensitive neutrinoless double-beta decay search, as well as additional searches for physics beyond the Standard Model. I will discuss the design elements that enable these searches, along with the latest results, focusing on the neutrinoless double-beta decay search. I will also discuss the current status and the future plans of the MAJORANA DEMONSTRATOR, as well as the plans for a future tonne-scale 76Ge experiment.

The Majorana Collaboration is operating an array of high-purity Ge detectors to search for the neutrinoless double-β decay of Ge76. The Majorana Demonstrator consists of 44.1 kg of Ge detectors (29.7 kg enriched to 88% in Ge76) split between two modules constructed from ultraclean materials. Both modules are contained in a low-background shield at the Sanford Underground Research Facility in Lead, South Dakota. We present updated results on the search for neutrinoless double-β decay in Ge76 with 26.0±0.5 kg yr of enriched exposure. With the Demonstrator's energy resolution of 2.53 keV FWHM at Qββ, which is the best among all neutrinoless double-β decay experiments, we observe one event in the region of interest with 0.65 events expected from the estimated background, resulting in a lower limit on the Ge76 neutrinoless double-β decay half-life of 2.7×1025 yr [90% confidence level (CL)] with a median sensitivity of 4.8×1025 yr (90% CL). Depending on the matrix elements used, a 90% CL upper limit on the effective Majorana neutrino mass in the range of 200-433 meV is obtained. The measured background in the configurations with full shielding and optimized grounding is 11.9±2.0 counts/(FWHM t yr).

Functional connectivity of blood oxygenation level dependent signal fluctuations (BOLD-FC) is decreased in Alzheimer's disease (AD), and suggested to reflect reduced coherence in neural population activity; however, as both neuronal and vascular-hemodynamic processes underlie BOLD signals, impaired perfusion might also contribute to reduced BOLD-FC; 42 AD patients and 27 controls underwent simultaneous PET/MR imaging. Resting-state functional MRI assessed BOLD co-activity to quantify BOLD-FC, pulsed arterial spin labeling (pASL) assessed cerebral blood flow (CBF) as proxy for vascular hemodynamics, and 18F-fluorodeoxyglucose PET assessed glucose metabolism (GluMet) to index neuronal activity. Patients' BOLD-FC, CBF, and GluMet were reduced within the same precuneal parietal regions. BOLD-FC was positively associated with mean CBF, specifically in patients and controlled for GluMet levels, suggesting that BOLD-FC reductions correlate with pASL-derived hypoperfusion in AD, independently from 18F-fluorodeoxyglucose PET-derived hypometabolism. Data indicate that impaired vascular hemodynamic processes contribute to reduced BOLD connectivity in AD.