bluuebunny/crossref_metadata_2025 huggingface dataset:
Combined Deletion of Free Fatty-Acid Receptors 1 and 4 Minimally Impacts Glucose Homeostasis in Mice
Authors: Croze Marine L , Guillaume Arthur , Ethier Mélanie , Fergusson Grace , Tremblay Caroline , Campbell Scott A , Maachi Hasna , Ghislain Julien , Poitout Vincent
Published: January 2021

The free fatty-acid receptors FFAR1 (GPR40) and FFAR4 (GPR120) are implicated in the regulation of insulin secretion and insulin sensitivity, respectively. Although GPR120 and GPR40 share similar ligands, few studies have addressed possible interactions between these 2 receptors in the control of glucose homeostasis. Here we generated mice deficient in gpr120 (Gpr120KO) or gpr40 (Gpr40KO), alone or in combination (Gpr120/40KO), and metabolically phenotyped male and female mice fed a normal chow or high-fat diet. We assessed insulin secretion in isolated mouse islets exposed to selective GPR120 and GPR40 agonists singly or in combination. Following normal chow feeding, body weight and energy intake were unaffected by deletion of either receptor, although fat mass increased in Gpr120KO females. Fasting blood glucose levels were mildly increased in Gpr120/40KO mice and in a sex-dependent manner in Gpr120KO and Gpr40KO animals. Oral glucose tolerance was slightly reduced in male Gpr120/40KO mice and in Gpr120KO females, whereas insulin secretion and insulin sensitivity were unaffected. In hyperglycemic clamps, the glucose infusion rate was lower in male Gpr120/40KO mice, but insulin and c-peptide levels were unaffected. No changes in glucose tolerance were observed in either single or double knock-out animals under high-fat feeding. In isolated islets from wild-type mice, the combination of selective GPR120 and GPR40 agonists additively increased insulin secretion. We conclude that while simultaneous activation of GPR120 and GPR40 enhances insulin secretion ex vivo, combined deletion of these 2 receptors only minimally affects glucose homeostasis in vivo in mice.
Parents Matter: Associations Between Parent Connectedness and Sexual Health Indicators Among Transgender and Gender‐Diverse Adolescents
Authors: Brown Camille , Eisenberg Marla E. , McMorris Barbara J. , Sieving Renee E.
Published: January 2021

CONTEXT

Transgender and gender‐diverse youth experience significant health disparities across numerous domains of health, including sexual health. Among general populations, parent connectedness has been strongly associated with youth sexual health.

METHODS

The relationships between parent connectedness and sexual health indicators were investigated among 2,168 transgender and gender‐diverse youth who participated in the 2016 Minnesota Student Survey, a statewide population‐based survey of ninth‐ and 11th‐grade students. Multivariate logistic regression models, stratified by sex assigned at birth, tested associations between parent connectedness—youth's perceptions of parent caring and parent–youth communication—and eight sexual health indicators: ever having had sex, having multiple sexual partners in the past year, pregnancy involvement, substance use at last sex, partner communication about STI prevention, partner communication about pregnancy prevention, condom use at last sex and pregnancy prevention methods at last sex.

RESULTS

The level of parent connectedness was inversely associated with ever having had sex, regardless of sex assigned at birth (odds ratios, 0.6–0.8). Although level of connectedness was inversely associated with having multiple sexual partners in the past year and pregnancy involvement among transgender and gender‐diverse youth assigned male at birth (0.6–0.7), these relationships were nonsignificant among transgender and gender‐diverse youth assigned female at birth. Further differences in associations between parent connectedness and four sexual risk–reduction behaviors were found between youth assigned male at birth and those assigned female.

CONCLUSIONS

As with other populations, parent connectedness promotes sexual health among transgender and gender‐diverse youth and may provide a point of intervention.
Injection locking and pulling phenomena in an optoelectronic oscillator
Authors: Fan Zhiqiang , Su Jun , Lin Yue , Jiang Di , Chen Yuan , Li Xiang , Qiu Qi
Published: January 2021

Injection locking and pulling characteristics of a long-loop optoelectronic oscillator (OEO) that has a large number of closely-spaced longitudinal modes are theoretically analyzed and experimentally evaluated. A differential phase equation that relates the phase difference between the OEO and the injected microwave signal to its instantaneous beat angular frequency is derived in the time domain. Based on the differential phase equation, both the locking and pulling characteristics of an injection-locked OEO are studied, and the phase noise performance is analyzed. It is found that the locking and pulling performance depends upon three parameters, the initial frequency difference between the frequency of the signal generated by the free-running OEO and frequency of the injected microwave signal, the voltage ratio between the signal generated by the free-running OEO and the injected microwave signal, and the Q factor of the free-running OEO. The phase noise performance depends upon the locking range, the phase noise performance of the free-running OEO as well as that of the injected microwave signal. The analysis is validated experimentally. Excellent agreement is found between the theoretical analysis and the experimental demonstration.
Ultrasensitive enhanced fabrication-tolerance refractometer based on PANDA-air-hole microfiber at the birefringent dispersion turning point
Authors: Xu Shengyao , Chang Weijie , Zhang Yang’an , Yuan Xueguang , Huang Yongqing , Ren Xiaomin
Published: January 2021

We present an ultrasensitive enhanced fabrication-tolerance refractometer utilizing the polarimetric interference of a tapered PANDA-air-hole fiber (PAHF). To obtain high birefringence and unique group birefringence, the PAHF is specially designed by introducing double air holes into the cladding. Ultrahigh sensitivity can be achieved by reducing the group birefringence difference to zero, defined as birefringent dispersion turning point (BDTP). By modifying the diameter of PAHF, the birefringent dispersion can be effectively manipulated to reduce the group birefringence difference. In this way, the workable diameter range for realizing the ultrahigh sensitivity is twice as large as that of conventional microfibers. Additionally, the ultrasensitive wavelength band is dramatically expanded by at least 600 nm, enabling a compact structure and a flexible fiber-length design. Due to the tunable dispersion optimization, the distinctive properties of ultrahigh sensitivity, enhanced fabrication tolerance, and broadband operation can be achieved. We experimentally verified the ultrahigh refractive index sensitivity of 47223 nm/RIU around the BDTP, and the experimental results matched well with the simulations.
Phase sensitive optical rotation measurement using the common-path heterodyne interferometry and a half-wave plate at a specific azimuth angle
Authors: Chiu Ming-Hung , Tan Chen-Tai , Wang Chun , He Jia-Nong
Published: January 2021

We proposed a new method for small optical rotation measurement. The method is based on the use of a half-wave plate and the high-stability common-path heterodyne interferometry. When the azimuth angle is at 22.5° of a half-wave plate, the phase has a distinct change caused by the small polarization rotation of the test beam. The optical rotation can be obtained from the relationship between the phase and the azimuth angle of the wave plate. The resolution of polarization rotation measurement can achieve 1.6 × 10−5 degree/mm and the detection sensitivity on circular birefringence of glucose-water solution can be up to δ|nr − nl | = 5.6 × 10−11.
The Lexeme «World» in the Modern Ergonomic Space (Based on the Names of Commercial Organizations in the Krasnodar Region)
Authors:   Краснодарское высшее военное авиационное училище летчиков имени Героя Советского Союза А.К. Серова, Дробан Виктория Владиславовна , Исаева Лидия Алексеевна ,   Кубанский государственный университет (Краснодар)
Published: January 2021

Статья посвящена выявлению формального, семантического и прагматического потенциала лексемы «мир» в современном эргонимическом пространстве Краснодарского края, рассмотренном на материале эргонимов с данной единицей и ее производными. Материалом исследования послужили эргонимы, зафиксированные в период с 2017 по 2019 год в процессе наблюдения над объектами городской среды, а также анализа баз 2gis.ru и Google Maps. Результатом исследования стала классификация эргонимов современного эргонимического пространства Краснодарского края с лексемой «мир», осуществляемая на основании их формальных, семантических, функциональных и прагматических особенностей. В статье отмечено, что эргонимы с лексемой «мир» в современном эргонимическом пространстве, рассмотренном на примере наименований коммерческих организаций Краснодарского края, образовали активную модель нейминга, способствующую реализации аттрактивной функции рекламного текста. Частотность объясняется особенностями лексемы «мир», проявляющимися в ее семантическом наполнении, способности к выражению концептуализированных общезначимых смыслов, а также в ее высоком манипулятивном потенциале, предопределенном структурой эргонима.
Literary and Dialectal Linguistic Identity as an Embodiment of Folklife and Linguistic Culture
Authors:   Кубанский государственный университет (Краснодар), Борисова Ольга Геннадиевна , Костина Людмила Юрьевна
Published: January 2021

В статье на примере конкретной литературно-диалектной творческой языковой личности (ЯЛ) жительницы станицы Старотитаровской Краснодарского края, обосновывается правомерность рассмотрения в качестве носителя традиционной народно-речевой культуры представителей сельской интеллигенции, испытавших влияние художественной литературы, текстов СМИ, но при этом знакомых с фольклором и усвоивших с детства традиции, этические, эстетические и речевые нормы диалектного сообщества. Рассматривается творческая деятельность изучаемой ЯЛ по созданию текстов на говоре, соответствующих фольклорному жанру бывальщины; анализируются собирательская работа по созданию сборника пословиц и фразеологизмов, составляющих личный пословично-фразеологический фонд ЯЛ, и лексикографическая – по подготовке словарных материалов для профессиональных диалектологов; делается вывод о развитом метаязыковом сознании ЯЛ, проявляющемся в способности дифференцировать диалектные слова, понимании важности фиксации места слова в лексической системе говора, а также в умении спонтанно приводить информативные контексты. В заключение высказывается идея о необходимости разработки типов крестьянской речевой культуры в среде современных сельских жителей и описания соответствующих им типов ЯЛ.
Archaisms and Neologisms in the Sphere of Professional Nominations (Exemplified in the German Language)
Authors:   Алтайский государственный педагогический университет (Барнаул), Кожанова Наталья Викторовна
Published: January 2021

В статье рассматриваются немецкие наименования лиц по профессии с точки зрения динамики их развития. Изменения, происходящие с течением времени, приводят к появлению архаизмов и неологизмов, имеющих свои особенности в анализируемой группе лексики. Устаревшие наименования лиц по профессии представлены, прежде всего, историзмами и семантическими архаизмами. Появление неологизмов является отражением естественного процесса эволюции лексической системы языка. Для данной лексики характерна высокая степень морфологической интегрированности. По способу образования выделяют заимствования, новообразования и абсолютные неологизмы. Особое внимание уделяется характеристике английских заимствованных наименований, которые представляют собой большинство среди общего числа заимствований в группе лиц по профессии на современном этапе развития языка. В качестве выводов отмечается важность комплексного изучения неологизмов и архаизмов в области наименований лиц по профессии, что позволяет подробно рассмотреть сущность процессов постоянной эволюции лексических систем и подсистем, а также прогнозировать вероятные изменения в системе наименований лиц по профессии, связанными с изменениями на рынке труда Германии.
Caricature on the Cover of a Print Medium: Requirements, Analysis (The New Yorker, The Week (Great Britain), Der Spiegel, The Spectator)
Authors:   Национальный исследовательский Мордовский государственный университет им. Н.П. Огарева (Саранск), Дементьева Ксения Владимировна , Кузьмина Марина Анатольевна ,   Национальная библиотека им. А.С. Пушкина Республики Мордовии (Саранск)
Published: January 2021

В статье рассматривается функционирование феномена карикатуры и сатирической иллюстрации как традиционного и обновленного метода социальной критики в журналистике и формата обложки печатного периодического издания. Целью работы является выявление особенностей феномена карикатуры и сатирической иллюстрации как традиционного и обновленного метода социальной критики в журналистике и формата обложки печатного периодического издания. В западной периодической печати иллюстрированная обложка чаще всего посвящена политическим темам, выполнена в жанре карикатуры и нацелена на мощную общественную реакцию. Карикатуры и иллюстрации могут выступать как самостоятельный материал, но в основном они являются способом сказать «недосказанное». Выявлена очевидная тенденция применения компьютерной графики даже в форме копирования традиционных техник в создании рассмотренных иллюстраций. Наиболее популярными у аудитории являются издания, публикующие резонансные обложки в смешанном стиле, политической тематики.
NUMERICAL STUDIES OF AIR FLOWS IN THE CABIN OF A UNIFIED MACHINE OF TECHNOLOGICAL ELECTRIC TRANSPORTAIMED AT ELIMINATINGMOISTURE CONDENSATION
Authors: Fil’kin N. M. , Tatarkin A. M.
Published: January 2021

This article discusses the process of creating a 3D-model of the cab of a unified machine of technological electric transport, generation of the calculated grid on the basis of the created model. Also, the parameters of the solver (Solution Setup) of the ANSYS Fluent software module for the study of the created model are selected. The main content of the study is the analysis of the results of modeling the airflow in the designed cabin. The analysis showed that the chosen cabin configuration will be able to eliminate the condensation process in critical areas. The conclusion is made about the need for further research, which will be aimed at developing the design of air ducts and used in the design of a unified machine of technological electric transport.
THE USE OF HYDRAULIC “LONG” LINES IN MODERN SUBSEA PRODUCTION FACILITIES
Authors: Trukhanov K. A.
Published: January 2021

Describes and provides a brief description of the modern application of hydraulic “long” lines in a subsea production facility. The necessity and relevance of developing a mathematical model that allows us to predict and carry out practical calculations of ongoing processes in hydraulic “long” lines, spending the minimum amount of time and resources on this, is shown. In the article are provided general provisions and basic mathematical relationships for performing calculations and modeling unsteady processes in hydraulic lines with distributed parameters. Boundary conditions are given that make it possible to obtain a closed system of equations representing a mathematical model of hydraulic “long” lines. The scientific novelty of the results presented in the article is that the main criteria necessary for the design and operation of equipment containing hydraulic “long” lines were obtained and presented. Among which it is especially necessary to note, dependences for the unsteady coefficient of hydraulic friction resistance of the pipe λ. Criteria are also given for determining the amplitude of signal attenuation in the case of using a hydraulic “long” line as a line for transmitting information, as well as a criterion that allows to determine the minimum pump flow rate to ensure a given level of purity of the working fluid during operation and maintenance of equipment with hydraulic “long” lines, which It is especially important and relevant in practice for the selection of equipment and determine the minimum required power. The content of the article is interest to specialists involved in the development of hydraulic systems with hydraulic “long” lines.
PRODUCTIVITY OF MACHINE TOOLS AND PRODUCTION SYSTEMS
Authors: Kondakov A. I.
Published: January 2021

Productivity is the most important indicator of labor efficiency. Productivity estimates poorly take into account the interaction of production systems equipment and the technological complexity of labor objects. There is proposed an integral assessment of the performance of these systems, which characterizes the effectiveness of the financial expenses of production resources in the manufacture of parts. It is proposed to characterize their technological complexity by multiplying the increase in the labor subject value after technological impact by the part release volume. The proposed assessment can be used in the development of software applications that automate the tasks of analyzing the effectiveness of production systems.
ALLOWANCE VALUES FOR CONTINUOUS ROLLING GEAR GRINDING OF CYLINDRICAL WHEELS
Authors: Kalashnikov A. S. , Morgunov Yu. A. , Kalashnikov P. A. , Karavanova A. G.
Published: January 2021

Designed and experimentally investigated the analytical method of determining the minimum value of the allowances at the side surfaces of the teeth of cylindrical gears taking into account the errors in the gear obtained in the preceding operation, and error compensation from the operation performed. For practical confirmation of the accuracy of the method of determining the allowance, an experimental gear grinding of a batch of satellites of the planetary gear of the cars automatic transmission was carried out. Based on the results of theoretical and experimental studies, recommendations were developed to determine the optimal values of allowances for the operation of grinding teeth.
KINETOSTATIC ANALYSIS OF DOUBLE-SATELLITE PLANETARY MECHANISM WITH ELLIPTICAL GEARWHEELS
Authors: Prikhod’ko A. A.
Published: January 2021

Non-circular gears can be used in modern machines and mechanisms for the implementation of various types of output link movement and have high strength and compactness compared to linkage mechanisms. The article considers the problem of kinetostatic analysis of the planetary mechanism, which provides the rotationally reciprocating motion of the stirred tank impeller. Proposed mechanism is a two-satellite single-row planetary gear with two external gears, in which one pair of gears is elliptical gearwheels. There are constructed calculation schemes, kinetostatic balance equations are compiled and solved for each link of the mechanism. There are found reactions in kinematic pairs and a balancing moment on the input shaft of the mechanism, which are presented as functions of forces on the angle of rotation of the input link. The results can be used in the synthesis, analysis and design of various machines and mechanisms with the proposed kinematic scheme of planetary gear.
THE CATHODIC PROTECTION SYSTEM OF PIPELINES WITH ANODIC EARTHING
Authors: Grinyuk O. N. , Larikov K. V. , Aleksashina O. V. , Parshina L. N.
Published: January 2021

In the article the method of calculation of anode grounding at electrochemical protection of pipelines for ensuring their reliable and safe operation, and also prevention of their destruction because of corrosion is considered.
THE INFLUENCE EVALUATION OF THERMAL TREATMENT ON MICROMECHANICAL PARAMETERS OF ALLOYED CORUNDUMS
Authors: Pushkariov O. I. , Kulik O. G. , Puzyrkova V. E.
Published: January 2021

The results of studies of the micromechanical parameters of alloyed electrocorundums are presented. It has been established that they are most effectively used in grinding processes after heat treatment at a temperature of 1250 С.
REDUCTION OF FORCES, MOMENTS OF FORCES AND INERTIA, EQUATION OF DRIVING GEAR MOTION, CHARACTERISTICS OF DRIVING GEAR OF HOISTING AND TRANSPORT, CONSTRUCTION, ROAD VEHICLES AND EQUIPMENT. THE SECOND LECTURE
Authors: Nizhegorodov A. I.
Published: January 2021

The paper deals with the material of the second lecture on the discipline “Theory of hoisting and transport, construction, road vehicles and equipment”. The focus of the course includes the reduction of forces, moments of forces and moments of inertia of rotating masses to the motor shaft, the reduction of progressive inertial mass along with the equation of driving gear motion, the time of its acceleration and braking, the pick-up of engines, driving gears of vehicles. A comparative assessment of the driving gears is given and the overload capacity along with the range of regulation of various engines and their mechanical characteristics are analyzed.
ELECTRONIC START-UP DEVICE FOR FEEDING AMALGAM LAMPS
Authors: Mikaeva S. A.
Published: January 2021

The article describes the devices of electronic start-up control apparatuses for feeding amalgam bactericidal lamps of various series. Technical and electrical characteristics are given, and single and group designs of electronic controlled starting and cooling devices are described. The types of wires in the types of connections of various designs of electronic start-up devices that supply lamps with a highly stable sinusoidal current with a frequency of 43 – 50 kHz are presented. Providing heating of the electrodes before starting the set current, “lighting” of lamps and with high accuracy supporting the discharge current of lamps with fluctuations in the phase voltage of the network from 180 to 250 V, providing all types of protection in normal and abnormal operating modes.
A. THEORY AND TECHNOLOGY OF CUTTING STEEL PIPES WITH A CIRCULAR SAW WITH INTERNAL TEETH
Authors: Filippov K. Yu. , Ramenskaya E. V. , Filippov Yu. A.
Published: January 2021

The paper deals with the design of circular and disk saws with different structural design, two of which have a patent of the “Technology of machine building” Department; performed theoretical development to determine the cutting power different from the standard method; the result of a production experiment for analyzing the cutting mode of aluminum pipes on the Italian cutting line. The results of the work are used in the educational process of the University.
CHARACTERISTICS OF ELECTRIC MOTORS, SYSTEMS OF HOISTING AND TRANSPORT, CONSTRUCTION, ROAD VEHICLES AND EQUIPMENT. THE THIRD LECTURE
Authors: Nizhegorodov A. I.
Published: January 2021

The material for the third lecture on the subject “Theory of hoisting and transport, construction, road vehicles and equipment” is the main focus of the paper including the most important issues for the characteristics of electric motors of hosting and transport, construction, road facilities and equipment, for the calculation of power of electric motors with the criterion of the activation duration and selection of engines for RMS power. In addition, it considers systems of hosting and transport, construction, road facilities and equipment, namely their power and speed tackle gears and concerns the efficiency of movable and fixed blocks of rope systems.
COMBINED FIRMWARE OF DEEP CHANNELS OF VARIABLE CROSS-SECTION
Authors: Smolentsev V. P. , Shirokozhukhova A. A. , Potashnikova N. S.
Published: January 2021

Variants of manufacturing deep channels of different cross-sections in typical details of modern equipment are considered. Most of the methods were created with the participation of the authors of the article and are protected by Russian patents. The results of the research are implemented in production at enterprises of various branches of mechanical engineering. Information is given about the original methods of piercing deep holes with a depth-to-diameter ratio of more than 25:1 by using combined processes with the imposition of high-frequency vibrations and the possibility of obtaining holes of variable cross-section in pressed ceramic and metal workpieces. The production of mating surfaces from small cross-section channels and narrow grooves is considered,which allowed us to offer an original technological process for the erosive chemical production of precision parts. This technology has been used in the manufacture of parts whose traditional processing methods are poorly understood or not feasible.In particular, a new application of combined firmware for obtaining deep holes of small cross-section in metal workpieces obtained by pressing is shown.Typical parts containing deep channels are given, the combined processing of which is the most technologically advanced and allows for a high economic effect.
RADIATION RESISTANCE OF QUARTZ GENERATORS
Authors: Vasilyeva L. A. , Boychuk M. I. , Mikaeva S. A.
Published: January 2021

The article presents the work on identifying the features of industrial technology of growing high-grade radiation-resistant quartz. In the course of work the analysis of marking of sections of the quartz devices used for production of the crystal elements which are a part of quartz generators in SMD cases is carried out, features of technology of production of crystal elements are reflected. As a result of the carried out works it is established that the crystal elements made of quartz crystals subjected to electrotreatment and thermophysical treatment by gamma irradiation and high-temperature annealing fully satisfy the requirements for radiation resistance under continuous and pulsed irradiations. Data on tests of samples of quartz generators GK108-P on resistance to influence of special factors of KGS “Climate-7” are resulted.
THE APPLICATION OF FLEXIBLE PRODUCTION SYSTEMS IN THE CONDITIONS OF THE PRODUCTION DIVERSIFICATION PROGRAM
Authors: Miroshin D. G. , Rychagova O. A.
Published: January 2021

The problems of diversification of production in a market economics are discussed in this article. The method of organizing machine-building production in the conditions of expanding the range of products of the enterprise is confirmed in the article. The production structure of the machine-building enterprise and methods of manufacturing organization: the process organization and the product organization, which are typical for the machine-building production automation system, are analyzed in the article. The process and result of developing a flexible manufacturing system, that is used to diversify production, its structure, main equipment, and transport system are described in the article. The structural scheme of the organization of a flexible production cell in the structure of a manufacturing system is given. The applied technological equipment, devices, systems and the process of its functioning are described. Technological capabilities of the equipment and transport system from a perspective of production diversification are given. The economic aspects and indicators of flexible manufacturing cells in a growing range of products under diversification are considered in the article.
AIR PRE-TREATMENT SYSTEM
Authors: Mikaeva S. A. , Mikaeva A. S. , Vasilyeva L. A. , Zheleznikova O. E.
Published: January 2021

The article describes the air pretreatment system designed to reduce high concentrations of hydrogen sulfide and volatile organic compounds through the use of specialized catalytic backfill. The system is a 20- or 40-foot insulated sea container in which two catalytic backfill units are located. One worker the other reserve. Each unit contains one cleaning step with a specialized ferruginous backfill. The installation does not have its own fan and is connected to the existing ventilation system be installed in front of the installation EVENTLET. The operation of the system is subject to all safety requirements for the operation of electrical equipment, which is powered by a voltage of 380 V and a frequency of 50/60 Hz. The technical characteristics and Assembly of the system are given.
REDUCTION OF THE TENSION OF MODIFIED TEETH OF NOVIKOV GEARING IN THE THREE-STEP GEARBOX Ц3НШ-450-40 DRIVE OF OIL PUMPING UNIT
Authors: Korotkin V. I. , Kolosova E. M.
Published: January 2021

The article is devoted to the actual topic – reduce the tension of the modified teeth of Novikov gearing drive gearbox of widely used oil pumping unit for oil production in order to increase the resource of their work and load-bearing capacity. As the object is considered a typical three-stage gearbox model Ц3НШ-450-40, produced by the plant “Izhneftemash” (Izhevsk). Gearbox is equipped with Novikov gearing with the basic rack profile according to GOST 15023–76. It is shown that the use of the proposed longitudinal modification of the working surfaces of the teeth in combination with an increase in gear module provides a very significant effect on reducing effective contact and bending stresses, on increase the load-bearing capacity and service life of the gearbox in comparison with the serial version currently produced by the domestic industry. The research is based on the results of solving the spatial contact problem of the stress-strain state of a tooth, as well as modeling the real multipoint engagement of Novikov gearing taking into account the technological errors of manufacture and assembly of gears. Recommendations on the implementation of the longitudinal modification of the teeth are given and it is shown that there are no technological difficulties. The effect achieved at different stages of the gearbox is: to reduce tooth stresses from 1.75 to 2.54 times, to increase the load-bearing capacity of the gearbox from 2.81 to 4.1 times, to increase the service life of the gearbox by an order of magnitude. In the future, the research outlined is supposed to spread to other models of gearboxes produced oil pumping units.
PASSIVE-ACTIVE EXOSKELET WITH VARIABLE LENGTH LINKS AND SPRING ELEMENTS OF TWO TYPES
Authors: Borisov A. V. , Volkova Yu. E. , Konchina L. V. , Maslova K. S.
Published: January 2021

The article considers a flat model of a passively active exoskeleton with links of variable length. The construction of a variable-length link, suitable for implementation in a robotic device in the form of a passively active exoskeleton, is as follows: at the ends of the link there are two sections of constant length having mass, between them there is a section of variable length, considered weightless. On a weightless area is a tension-compression spring, which ensures the maintenance of the link length and energy recovery during the movement of a person in the exoskeleton. A torsion spring is installed in each hinge, which provides energy recovery with relative rotational movement of the links. The application of the proposed model in the form of a passively active exoskeleton with spring elements will allow a person to reduce the load on the joints and increase strength, endurance due to energy recovery, increase comfort and time of continuous use. It is possible to use the proposed model in the rehabilitation process to restore impaired functions of the human musculoskeletal system.
METHODS FOR COOLING THE HOT ZONE OF HEAT ENGINES AND TECHNOLOGICAL TECHNIQUES FOR IMPLEMENTING THE METHODS
Authors: Panichev E. V. , Smolentsev V. P. , Shchednov A. V.
Published: January 2021

Various types of hot zone cooling systems for liquid rocket engines are considered. The analysis of systems for external and internal cooling of the hot zone of the combustion chamber and the jet co-PLA is performed. The area of primary use of external and internal impact of components on the combustion chamber and the jet nozzle of a temporary product with a high thermal load on the material is given. Recommendations on the choice of technological methods for processing heat-protective coatings were developed, where the advantages of combined electroabrasive treatment were revealed. In this case, the possibility of finishing the transition sections of the path from areas that are difficult to access for the tool, which have coatings with ceramic granules that have been used in the latest products of aerospace technology, is shown. The mechanism of heat transfer by the cooling medium from the areas of the greatest heating, as a rule, to the flow of the liquid fuel component of the fuel is shown. Examples of implementation of modern cooling systems on typical designs of combustion chambers of modern rocket engines are considered. It is shown that the cooling efficiency will be higher the more belts of the cooling medium curtain are located along the length of the combustion chamber. At the same time, it should be taken into account that the use of an excessively large number of belts means a significant complication of the camera design, its manufacturing technology, and an increase in the cost of the product.
FEATURES OF MANUFACTURING TECHNOLOGY FOR THIN-WALLED PARTS
Authors: Blinov D. S. , Chunosov I. S.
Published: January 2021

In Russia, there is a tendency to revive the machine tool industry. From here, research in the field of mechanical engineering technology becomes relevant. The most popular research in the field of mechanical engineering technology is research on improving the manufacturing technology of thin-walled parts based on more reliable calculations. Axisymmetric thin-walled parts are very widely used in mechanical engineering, and they can be divided into rings and shells depending on the ratio of length to diameter. The objects of research in the article, which is staged in the cycle of works, are rings. The review and analysis of devices for installing thin-walled parts and methods for calculating errors from the action of fixing forces and cutting forces showed that standard cartridges are most often used for installing rings, and in the calculations of fixing forces are assumed to be concentrated (applied at a point). The work offers special devices–mandrels with wide cams, which are advisable to use when installing rings in mass production. The rings have a tolerance for the diameter of the base hole, which is intended to be used in the study. The purpose of the study is to develop an engineering method for calculating the shape error in the cross section of a thin-walled ring fixed by three wide mandrel сams, taking into account the width of the contact area and the initial radial gap between the diameter of the workpiece hole and the diameter of the working cylindrical surface of the cam. The tasks that will allow you to achieve the goal, the initial data, and a number of assumptions to simplify the study are identified.
RELIABILITY ANALYSIS OF REINFORCED CONCRETE FLEXURAL ELEMENT ON CRACKING BASED ON FRACTURE MECHANICS
Authors: Solov’ev S. A. , Yarygina O. V.
Published: January 2021

The article describes a probabilistic approach to the reliability analysis of a flexural reinforced concrete element by the cracking criterion using the provisions of fracture mechanics. Two mathematical models of limit state are proposed for reliability analysis: with the evaluation of the critical stress intensity coefficient directly and through the design concrete compressive strength. On the basis of regression analysis, the relationship between the critical stress intensity coefficient and the design concrete compressive strength is established which can be used in the inspection of reinforced concrete structural elements. The influence of the design concrete compressive strength on the failure (cracking) probability of the flexural reinforced concrete element is analyzed. The numerical example of reliability analysis is given for the reinforced concrete beam by the criterion of cracking. It is noted that the required level of reliability should be set for each structural object individually based on the acceptable risk value using economic and non-economic losses.
SIMULATION OF GAS RELEASE FLOWS FROM THE FLOW SURFACES OF TURBOMOLECULAR VACUUM PUMPS
Authors: Fomin M. V. , Fomina I. M.
Published: January 2021

An algorithm for modeling and an example of calculating gas release flows from the surfaces of the flow part of a turbomolecular pump by the Monte Carlo method in a three-dimensional setting low-density gas flow is considered.
PUNCHING CUPS WITH BOTTOM FLANGE BY DIRECT EXTRUSION WITH COUNTER-PUNCH. DETERMINATION OF KINEMATIC AND STRESS STATES IN THE SECOND PERIPHERAL REGION OF PLASTIC DEFORMATION
Authors: Vorontsov A. L. , Nikiforov I. A.
Published: January 2021

Using the theory of plastic flow according to the method of A. L. Vorontsov, the formulas are obtained that are necessary for calculating the stresses and force parameters of the extrusion process with counter-punch of the peripheral region adjacent to the container with the matrix. The maximum pressure acting on the matrix wall and the height of the peripheral region of plastic deformation are determined.
PUNCHING CUPS WITH BOTTOM FLANGE BY DIRECT EXTRUSION WITH COUNTER-PUNCH. DETERMINATION OF KINEMATIC AND STRESS STATES IN THE THIRD CENTRAL REGION OF PLASTIC DEFORMATION
Authors: Vorontsov A. L. , Nikiforov I. A.
Published: January 2021

Using the theory of plastic flow according to the method of A. L. Vorontsov, the formulas are obtained that are necessary for calculating the stresses and force parameters of extrusion with a counter-punch of the central region of plastic deformation adjacent to the formed wall of the product.
PUNCHING CUPS WITH BOTTOM FLANGE BY DIRECT EXTRUSION WITH COUNTER-PUNCH. DETERMINATION OF KINEMATIC AND STRESS STATES IN THE FOURTH CENTRAL REGION OF PLASTIC DEFORMATION
Authors: Vorontsov A. L. , Nikiforov I. A.
Published: January 2021

Using the theory of plastic flow according to the method of A. L. Vorontsov, the formulas are obtained that are necessary for calculating the stresses and force parameters of extrusion with the counter-punch of the central region of plastic deformation abutting against the working end face of the counter-punch.
PUNCHING CUPS WITH BOTTOM FLANGE BY DIRECT EXTRUSION WITH COUNTER-PUNCH. DETERMINATION OF THE DEFORMED STATE DURING CONSTRAINED EXTRUSION IN THE SECOND PERIPHERAL REGION PLASTIC DEFORMATION
Authors: Vorontsov A. L. , Nikiforov I. A.
Published: January 2021

The formulas necessary for calculating the accumulated deformations obtained in the process of constrained extrusion of the peripheral region adjacent to the formed wall of the product are obtained. To derive the formulas, the general method of plastic flow A. L. Vorontsova. The obtained formulas allow us to determine the deformed state of the workpiece at any point in this area. Further, these formulas will be used to take into account the hardening of extruded material.
DEVELOPMENT OF A METHOD FOR SYNTHESIZING AN APERTURE DIAPHRAGM IN HYPERSPECTRAL REMOTE SENSING SYSTEMS FOR EARTH
Authors: Kuznecov A. Yu. , Sadikova A. A. , Gornyj V. I. , Latypov I. Sh.
Published: January 2021

The aim of the work is to research and develop methods for synthesizing aperture in hyperspectral systems for remote sensing of the Earth to reduce weight and size characteristics by applying methods of program-algorithmic processing of the input signal and implementing the synthesized aperture. A method of neural networks for deconvolution on the construction of a radial basis network is developed. A method has been developed to increase the synthesis of apertures in hyperspectral systems for remote sensing of the Earth. A method for increasing the spatial resolution of images obtained by optical systems for remote sensing of the Earth is described. A method for radiometric calibration of output data has been developed, which allows universalizing the analysis of spectral characteristics. In the process, to achieve the goals were used: methods of spectral optics, mathematical analysis and statistics, methods of processing images and signals. The project results contribute to the reduction of overall weight and cost characteristics and the possibility of synthesizing the aperture at the exit of the polychromator, which will avoid the use of expensive camera lenses in hyperspectral systems of remote sensing of the Earth. The developed methods for synthesizing aperture in hyperspectral systems of remote sensing of the Earth differ from the existing ones in that the receiving device for the video signal does not contain structural changes, and they contain the function of the algorithmic apparatus, which includes the analysis of the functions of the scattering point, the deconvolution of the recorded signal is performed by the method of neural networks after the stage learning.
STATISTICAL AND MACHINE LEARNING HIGH-FREQUENCY TIME SERIES FORECASTING METHODS IN AUTOMATIC MODE
Authors: Cuong Sai Van , Shcherbakov M. V.
Published: January 2021

The research of the problem of automatic high-frequency time series forecasting (without expert) is devoted. The efficiency of high-frequency time series forecasting using different statistical and machine learning modelsis investigated. Theclassical statistical forecasting methods are compared with neural network models based on 1000 synthetic sets of high-frequency data. The neural network models give better prediction results, however, it takes more time to compute compared to statistical approaches.
AUTOMATICAL PRETRANSLATION OF SQL-QUERIES TO A REGULAR PLAN IN CLUSTERIX-LIKE DBMS
Authors: Klassen R. K. , Kazantsev I. A.
Published: January 2021

Previously completed designs for pretranslating SQL queries did not bring significant success. Nevertheless, such a pretranslator is necessary for the possibility of using Clusterix-like database management systems (DBMSs) by a wide circle of specialists. The article proposes an original approach to pretranslating SQL queries without writing operations to the regular plan for Clusterix-like DBMSs. The possibility of implementing such a pretranslator is discussed. The concepts of a hard and a simple SQL query are given. The basis of the pretranslator is a library for parsing arbitrary grammars antlr4, which is used to build a SQL query tree. A software-implemented pretranslator uses it to build queries that meet the regular plan.
MODELING OF INTELLECTUAL CONTROL SYSTEMS WITH APPLICATION OF MODIFIED FUZZY COLORED PETRI NETS
Authors: Huseynzade Sh. S.
Published: January 2021

A modification of the Petri nets is proposed  a Fuzzy Colored Petri Net (FCPN), leading to the integration of Fuzzy Petri Nets (FPN) and Colored Petri Nets (CPN). Separately, the shortcomings of FPN and CPN and the advantages the developed FCPN for modeling intelligent control systems are identified and justified. In the developed modified FCPN the membership functions of the terms of a linguistic variable are applied to markers of the CPN as color and fuzzy existence conditions are assigned to arcs depending on the values of the linguistic variable. As a result, FCPN with enhanced capabilities was obtained, which eliminates the shortcomings of CPN and FPN. The FCPN and a simulation approach are defined, which includes a reasoning algorithm, as well as a detailed procedure for modeling and analysis of nonlinear discrete objects. The structure is organized in the CPN Tools system with the synchronization of the CPN ML (Markup Language) language with the MatLab package. The choice of membership function and fuzzification of term values is performed in the Fuzzy Toolbox application of the MatLab system. The proposed approach is illustrated by simple example, including the control of water pumps, to maintain the required water level in the pumping well. A model is developed for the automation of adaptive fuzzy control of water pumps based on modified FCPN. Based on the criteria for the operation of water pumps according to the water levels in the pumping well, many positions and transitions of the FCPN are formed. Describing the necessary behavior of the system by the relations between the positions and transitions of the FCPN using the logic “If ... Then ...” an adaptation algorithm is developed. Based on the algorithm, the matrices of input and output incidents are determined. The graph model of the FCPN is developed. Visualization of the model is implemented in the CPN Tools system. The computer simulations and net analysis experiments demonstrate the convenience of the developed approach when modeling the intelligent control of dynamic systems.
MODEL OF STANDARD FOR INFORMATION RETRIEVAL IN THE COLLECTION OF REGULATORY FRAMEWORK DOCUMENTS
Authors: Butenko Yu. I.
Published: January 2021

The article proposes a model of the standards’ texts for information retrieval in the collection of documents the regulatory framework. It is proved that the standard means of information retrieval in the collection texts of standards are ineffective due to the compositional features of the texts and the wide use of generalized and abstract vocabulary. Distinctive stylistic features of standards’ texts in normative base are shown in compositional structure, logic of material representation, compactness. It is noted that the standards’ texts have the same structure of material presentation for all texts of this class, and also contain a limited set of structural elements. The description of structural elements of standards is given. It is proved that the compositional structure of the standard’s text has a significant impact on the results of information retrieval in the collection of documents the regulatory framework. The compositional structure of the standard in the Backus-Naur notations is presented. It is developed the model of the standards’ text in the form of a graph, the vertices and edges of which are full-fledged structural elements of the standard, significant both for the content of the text as a whole, and in terms of information retrieval. It is proved that the presentation of the standard’s text in the form of a graph makes it possible in the process of computer analysis the standard’s text to determine the type of structural element, the degree of nesting, by submitting the standard in the form of a finite set of its components.
Evolution of space debris for spacecraft in the Sun-synchronous orbit
Authors: Jiang Yu , Li Hengnian , Yang Yue
Published: January 2021

In this paper, the evolution of space debris for spacecraft in the Sun-Synchronous orbit has been investigated. The impact motion, the evolution of debris from the Sun-Synchronous orbit, as well as the evolution of debris clouds from the quasi-Sun-Synchronous orbit have been studied. The formulas to calculate the evolution of debris objects have been derived. The relative relationships of the velocity error and the rate of change of the right ascension of the ascending node have been presented. Three debris objects with different orbital parameters have been selected to investigate the evolution of space debris caused by the Sun-Synchronous orbit. The debris objects may stay in quasi-Sun-Synchronous orbits or non-Sun-Synchronous orbits, which depend on the initial velocity errors of these objects.
Mathematics Teaching in Slovakia during COVID-19 Quarantine Season in Spring of 2020
Authors: Csachová Lucia , Jurečková Mária
Published: January 2021

In many countries, the attendance form of education was interrupted during quarantine in the spring of 2020 and replaced by some form of distance education. The COVID-19 pandemic has thus tested the preparedness of schools, teachers and educational systems in general to provide various forms of distance education. This paper briefly describes the situation in mathematics teaching in lower and upper secondary schools during the spring quarantine in Slovakia. We focus on the initial reactions and early experience of mathematics teachers. They have used different applications, software and methods in teaching mathematics during this time. Our goal is not to evaluate whether the teachers managed it or not, but what and how they had to do so that the educational process in mathematics would not be interrupted.