bluuebunny/crossref_metadata_2025 huggingface dataset:
Advantages and Limitations of Seismic Refraction Method Using Hammer Sources
Authors: Washima Awuha , A. M George , Anti Kur , Luper Tsenum Joseph
Published: January 2021

The seismic refraction surveying method uses seismic energy that returns to the surface after traveling through the ground along refracted ray paths. The first arrival of seismic energy at a detector offset from a seismic source always represents either a direct ray or a refracted ray. This fact allows simple refraction surveys to be performed in which attention is concentrated solely on the first arrival (or onset) of seismic energy, and timedistance plots of these first arrivals are interpreted to derive information on the depth to refracting interfaces. this simple approach does not always yield a full or accurate picture of the subsurface. In such circumstances more complex interpretations may be applied. The method is normally used to locate refracting interfaces (refractors) separating layers of different seismic velocity, but the method is also applicable in cases where velocity varies smoothly as a function of depth or laterally.Despite the numerous limitation of hammer seismic refraction survey, the technique is still very much in use due to the various aspects in which it is found advantageous. The most pronounce advantage of the refraction method is that it gives directly the velocities of the refracting beds. Which are needed in the depth interpretation.

This this work reveals that even though there are several problem of this technique, there are also a lot of advantages, one of which is that it is the most readily available seismic energy source we can lay hands on.Hammer source is a low energy source whose use is restricted to shallow survey. Due to weak energy generated,only the first few layers of the ground subsurface can be detected. It provides only the picture of the bedrock configuration. When there arises problems such as noise, irregularities in the shallow bedrock surface or eroded and weathered rock surface, anisotropic surface, existence of blind zone, velocity reversal with depth, and when the boundary between the interfaces are non-parallel, then correction measures are necessary to improve on the results obtained. Ambiguities do occur in this technique hence it requires thought, care, a high degree of skill and a good sense of judgment.These shortcomings are not enough to dismiss the use of the hammer source in seismic refraction method as its results has been shown to be useful in solving civil engineering and hydrogeological problems. The method is economical in cost, time and area of coverage. It poses no danger to the environment to which the work is done, or neither personnel nor damage to instruments used. This work has not only enumerated the limitations and advantages of seismic refraction method using hammer source but has also made suggestions to aid in the basic problem of the method, like dipping layers, blind zone, velocity inversion occurrence and noise control.
The plant-based-diet and obesity : The process and literature survey
Authors: Sanghvi Roshni , Gordon Anna
Published: January 2021

There are an increasingly rising number of people who adopt a plant-based diet. The desire for weight control and other health benefits are driving factors behind this dietary preference. The aim of this study was twofold: first, it reviews intervention studies evaluating the impact on body mass index and weight by various plant-based diets. Most of them were randomized controlled trials of overweight, type 2 diabetes mellitus and/or cardiovascular disease participants compared a low-fat vegan diet to an omnivore diet. Second, this study reviews two major dietary processthat may lead to reduced-body fat. Interventional trials have consistently demonstrated that consumption of plant-based diets reduces body fat in overweight and obese subjects, even when controlling for energy intake. Nonetheless, the mechanisms underlying this effect have not been well-defined. Our review indicatesthat in some patient groups, plant-based diets can enhance weight condition. In certain studies, due to fat consumption limits accompanied by decreased energy intake, the results of the various treatments vary depending on the particular plant-based diets studied. Future research should seek to include a representative population of the sample and apply diets without dietary limitations to the study.
Autism Revisited:

Serendipitous Observations and Theory
Relevant To Autism
Authors: Ogman Russel
Published: January 2021

Abstract: It is hypothesized that the measles N protein component of the measles virus,chronically interferes with a specific homeostatic mechanism that provides balance between metabolic and immune function, resulting in autism. First, congenital metabolic diseases or risk factors, produce Primary Local and Continuing Suppressions of enzymatic and immune functions. Critical among these risk factors is extremely low or non-existent secretory IgA. Second, the overall cellular homeostatic environment is then severely effected by Global and Transient Metabolic and Immune Suppressions from the measles vaccination. Third, the combination of severe immune/enzymatic suppressions from the measles virus, severely reduced secretory IgA, and other CMD's, allows opportunistic infections to flourish, which support secondary immune and enzyme suppressions. Finally, all these suppressions produce a severe intracellular messenger-metabolite flux reduction, which allows the measles N protein freedom to interact, and interfere with, the eukaryotic initiation factor eIF3P40. eIF3P40 is joined to the eukaryotic initiation factor eIF4E through an eIF4G linkage. Theoretically, this would create a severe dysregulation in the eukaryotic initiation factor eIF4E, which has been observed in autistic children, and associated with autistic behavior in animal studies. The severe repressions from reduced secretory IgA and other CMD's, immune repression from opportunistic infections and consequent and continuing measles virus latency, results in an ongoing inability to achieve homeostasis between metabolic functions and immune functions. This manifests as autism. Three tests of this theory are possible. First, treatment with human derived measles N protein specific secretory immunoglobulin A, which is capable of neutralizing the interference. Theoretically, such a test/treatment would restore homeostasis, with a gradual improvement of the autistic condition. Second, it is proposed that if measles N protein specific secretory IgA is properly administered concurrent to infant measles vaccination, few if any cases of autism should be observed, while still providing protection against measles. Third, immunization of the mother with MMR vaccine and subsequent immunization of the child during concurrent breastfeeding. Theoretically, children could then receive sufficient measles specific secretory IgA via breast milk with few if any cases of autism (or measles) observed. If correct, these tests could provide empirical evidence of an indirect relationship between autism and measles virus/ vaccination.
Steady Magnetohydrondynamic Natural Convection Coutte Flow With Variable Electrical Conductivity
Authors: Tuleun Terhemen
Published: January 2021

The steady MAGNETOHYDRODYNAMIC natural convection coutte flow of viscous incompressible and electrically conducting fluid having variable electrical conductivity between two parallel plates when one of the plate is set into motion is studied. The dimensionless differential equations as well as energy equations are solved analytically using the method of undetermined coefficient. The analytical solution are presented numerically inform of line graphs given interms of velocity and skin friction. The result reveal that the effect of the Hartmann number and grashof number are to reduce and increase the velocity respectively. Similarly the skin friction on the moving and stationary plates increase with Grashof number and decreases with increase in Hartmann, a comparetive study review that the effect of Hartmann number and grashof number on velocity and skin friction are same.
MODELING AND MONITORING OF THERMODYNAMIC PROCESSES IN SYNCHRONOUS ELECTRIC MOTORS
Authors: Kryukov O. V. , Stepanov S. E. , Vasenin A. B.
Published: January 2021

Methods are given for the mathematical description of thermodynamic processes in the insulation of drive motors of alternating current megawatt class. The paper presents the requirements for equipping monitoring systems of the main technological equipment and electric machines, in particular, which regulate the monitoring of working capacity, reliability and safety of equipment using reliable technical and software tools. The most appropriate when choosing a monitoring model for synchronous motors is a functional diagnostic model, when using which the input actions of elementary checks are determined in advance by the working algorithm of the object, and only the composition of the controlled parameters of the diagnostic object is subject to selection. For a predictive analysis of the temperature of the windings of a synchronous machine, a three-stage heating theory is used, in which the motor is divided into a stator winding, a steel structure of the stator and a rotor. In addition, the models take into account the mechanical loads acting on the insulation of the stator windings in various modes during operation: electrodynamic, vibrational and thermomechanical. The results of the analysis of the dynamics of thermodynamic processes in the stator windings of machines with refinements related to the effects of cooling methods, the finning of the external surface of the machine, the heat sink through the frame and bearing shields, as well as the influence of a significant amount of air inside the thermal circuits of synchronous motors. For engineering calculations, algorithms for determining electrodynamic forces are recommended, taking into account simplifying assumptions that do not affect the accuracy of the practical assessment of the forces acting on the isolation of powerful machines. The determination of only some of the main components of the effects, which include the forces caused by the interaction of currents of one phase and acting on the extreme rod of the phase group in the involute part of the rod along the corresponding curves, is also justified.
VI ALL-RUSSIAN SCIENTIFIC AND PRACTICAL CONFERENCE OF X-RAY EQUIPMENT MANUFACTURERS
Authors: Artemyeva O. B. , Artemiev B. V. , Galkin D. I. , Potrakhov N. N.
Published: January 2021

A brief overview of the most interesting reports and events held on November 28–29, 2019 at the St. Petersburg State Electrotechnical University "VI All-Russian Scientific and Practical Conference of X-ray Manufacturers" is presented. As a result of the work, a collection of conference materials was released. The central event of the conference was an excursion to the plant of JSC Svetlana-X-ray, where the general director is Ph.D. N. A. Kulikov spoke in detail about the existing production technologies and plans for the future, after which a tour was conducted on all the shops of the enterprise. The conference reports were divided into two areas: “Technical means of medical diagnostics” and “Methods of using technical means of medical diagnostics”, although some reports did not fully comply with the aforementioned topics. The conference organizers consciously took such a step so as not to split the meetings into a large number of sections. The most interesting and informative reports were made on the section “Technical means”. For novice researchers and graduate students of Russian universities, special conditions were created that allowed them to participate in the conference with their own reports. More information about the conference materials can be found on the website http://www.x-ray-conf.ru/, which contains the materials of all previous conferences starting from the first All-Russian Conference of X-ray Equipment Manufacturers held in St. Petersburg on November 21, 2014.
DETECTION OF ADHESION-FREE AREAS AND EXFOLIATIONS IN MULTILAYER STRUCTURES BY THE ACOUSTIC-TOPOGRAPHIC METHOD
Authors: Murashov V. V.
Published: January 2021

Physical the bases of acoustic-topographic method of defektoskopiya of multilayer structures are briefly covered. Installation for implementation of acoustic-topographic method in two options is developed and mounted: with the magnetostrictive activator and with the electromagnetic (shock) activator. By pilot studies it is established that at control by acoustic-topographic method of brazed and welded structures sensitivity of control significantly (in 2–3 times) is higher, than at control by other methods of defektoskopiya. It is established also that the zone of control of multilayer glued structures is much less, than at control of brazed and welded structures. It is shown that the greatest thickness of the upper leaf of structure at which control by acoustic-topographic method with sufficient sensitivity is still possible, is equal to about 1 mm, at control of structures with thickness of the upper leaf initiation of elastic oscillations it is reasonable to carry out over 1 mm in the shock way. Repeated control with change of point of input of ultrasonic oscillations is in certain cases necessary for specification of picture of distribution of powder near initial point of input of oscillations.
ACOUSTIC EMISSION TESTING OF POWER TRANSFORMERS INSULATION
Authors: Bardakov V. V. , Elizarov S. V. , Barat V. A. , Kharebov V. G. , Medvedev K. A.
Published: January 2021

Testing results of power transformers insulation for the presence of insulation defects, accompanied by the partial discharges occurrence, by means of the acoustic emission method are presented in this article. In particular, the testing of two power transformers with different lifetime was carried out. One transformer was defect-free and one with a willing insulation defect. Based on the testing results, the features of acoustic emission data for power transformers in the presence of partial discharges are found. High sensitivity of acoustic emission method for acoustic wave registration from partial discharges is shown in the article. A method for filtering of noise hits and extraction of hits from partial discharges is proposed. This method is based on excretion of acoustic emission hits from partial discharges out of total number of hits by means of periodicity of their registration, which is synchronized with power supply frequency on the first step. On the next step based on acoustic emission parameters of hits excretion on the previous step, filtration was carried out. The location of the insulation defect which led to the appearance of partial discharges was determined based on the volume location algorithm, by means of acoustic emission method. The insulation defect was confirmed by verification.
ACOUSTIC EXPRESS METHOD FOR MEASURING ELASTIC METAL CONSTANTS OF HIGH-LOADED CONSTRUCTIONS WORKING IN EXTREME CONDITIONS. PART 1
Authors: Bobrov V. T. , Bobrenko V. M. , Gulshin A. V.
Published: January 2021

A review of contingencies related to the failure of potentially hazardous equipment of the aviation and space-rocket complexes showed that they lead to explosions, fires, deaths and destruction of infrastructure. The causes of accidents and disasters are errors in the selection of technical solutions and materials during design, imperfection of algorithms and software for flight control systems, malfunctions in on-board computers and security systems, navigation systems, engine failure, defects in components and assemblies. Examples of accidents and disasters related to technical failures leading to a violation of the tightness of the aircraft fuselage and depressurization of spacecraft are given. It is shown that the main types of damage to the units are corrosion damage, fatigue and metal wear. The conclusion is made about the negative impact of the “human factor” regarding the adoption of erroneous decisions, failure to comply with regulatory requirements and actions in extreme situations. There is a risk of fatigue cracks and degradation of the properties of stringer metal, landing gear struts, wing tail trim, fuel tanks, engine pylon flanges, and imperfect methods, equipment, and technology for monitoring fatigue defects of critical components and mechanisms of aircraft, helicopters, and space systems. It is shown that modern achievements are poorly used in research and development of physical methods and diagnostics of elastic constants of metals working under high pressure, their changes in conditions of wide temperature drops, cosmic vacuum, vibration and other influences. It is proposed to combine efforts with scientists and experts in the field of strength, resource assessment and operational safety of aviation and space technology.
IDENTIFICATION AND RELIABILITY OF CONTROL IN ULTRASONIC FLAW DETECTION AND DEFECTOMETRY
Authors: Badalyan V. G.
Published: January 2021

The effectiveness of methods and means of ultrasonic non-destructive control (ultrasonic control) is evaluated by the probability of detecting defects and the reliability of the results of the control. In this work, we reserch the behavior of PoD(a) – the defect detection function, which describes the dependence of the probability of detection of defects on their height, and estimates the reliability of control by means of ROC analysis of the control data. An analysis of the PoD curves obtained by ultrasonic testing with ultrasonic flaw detection and ultrasonic flaw detection instruments demonstrates significantly greater reliability of the use of defectometry techniques and devices. ROC curves constructed using ultrasonic defectometry data make it possible to evaluate the reliability of control of defects of various heights. Analysis of ROC curves provides additional information for optimizing ultrasonic control techniques. The studies were carried out on the data array of ultrasonic testing of welded joints with real cracks.
A NEW APPROACH TO ASSESSING THE OPERATIONAL SAFETY OF COMPOSITE MATERIALS AND PARTS OF COMPLEX STRUCTURES BASED ON ARTIFICIAL INTELLIGENCE METHODS AS A PART OF NEURAL NETWORKS AND DEEP RESULTS OF MULTI-CRITERIA COMPLEX NON-DESTRUCTIVE TESTING
Authors: Akimov D. A. , Kleymenov A. D. , Kozelskaya S. O. , Budadin O. N.
Published: January 2021

The article proposes a new approach to assessing the operational safety of materials and parts of complex structures based on artificial intelligence methods based on artificial neural networks and multi-criteria complex non-destructive testing, and special mathematical and algorithmic support for systems for evaluating operational safety and predicting residual life under external influences. A method of morphological analysis of the procedures for using measurement tools for heterogeneous information with different a priori information, both about the type of characteristics and the distribution of errors in the input and output signals, has been developed. The classification of problems of measuring parameters for the integration of heterogeneous information is proposed. A macromodel of error is obtained that can be used for research purposes to minimize errors in the developed equipment or for the purpose of correcting errors during operation. A classification of methods for measuring heterogeneous information from the standpoint of probability distribution theory is proposed. Experimental testing of developed algorithms tailored aggregation of information non-destructive testing and adaptation to poorly formalized parameters, which confirmed the effectiveness of the developed methods and algorithms for assessment of structures and resource forecasting their operational reliability was carried out.
NEW TECHNICAL SOLUTIONS IN THE PRACTICE OF OPERATIONAL EVALUATION OF RESISTANCE OF PIPELINE INSULATION
Authors: Grigoryan L. R. , Bogatov N. M.
Published: January 2021

These volumes explore method for the rapid assessment of the insulation resistance of underground pipelines in order to reduce the duration and complexity of route work in the process of electrometric inspection of utilities. The idea of the method is based on the representation of a pipeline in the form of a metal-electrolyte electrochemical system, along the boundary of which a double layer of charged particles is formed, which can be logically represented as an equivalent electrolytic capacitor. This allows you to use the push-pull controlled discharge of the capacitor followed by mathematical processing of the two discharge equations and determine the absolute value of the insulation resistance of the pipeline in almost real time. The work provides a theoretical evaluation of the method and conducts a constructive and technological analysis of its practical implementation. The engineering calculation of the discharge resistance values confirmed the reliability of the proposed method for assessing the insuation resistance of pipelines.
ABOUT SOME FEATURES OF APPLICATION OF A TANDEM TECHNIQUE IN THE ULTRASONIC TESTING
Authors: Danilov V. N.
Published: January 2021

On the basis of received before the formula of an acoustic сhannel for the circuit of the ultrasonic control the tandem technique and a reflector as a side drilled hole carries out calculations echo signals for various base distances, depths of reflector and angles of probes. Influence on amplitude of a registered signal of a choice of position of a point of reflection on depth of the control is shown. It is established, that mutual replacement of positions of transmitting and receiving probes with identical parameters in a tandem technique practically has not an effect for amplitude of a registered signal. Influence on amplitude of a signal of distinction of angles of transmitting and receiving probes is shown. Comparison of the signals received at use of the circuit of the control on a tandem technique with reflection of a shear wave from a bottom surface and at use of the circuit of a path for separate angle probes with reflection of a wave only from a surface of defect has shown, that a choice of base distance between probess for the point of reflection which are taking place on small distance from a bottom surface, provides also an opportunity of detection of volumetric defects on significant distance from this surface.
MATERIALS SCIENCE RESEARCH DEFECT OCCURRENCE AND RUPTURE OF THE GAS PUMPING UNIT AXIAL COMPRESSOR BLADE
Authors: Ramazanov R. M. , Ramazanov M. I. , Sapargaliev T. A. , Kim A. V.
Published: January 2021

The article discusses the results of the study of the causes of destruction of the axial compressor blade and the causes of the defect of the working blade 10 stage GTU GPA type GTK-10-4 station No. 18 of the compressor station “Dzhangala”. The blade is made of X20Cr13 steel (AISI 420). The blades have an operating time of 23 284 hours after the last repair. Chemical analysis, fractographic analysis, and hardness measurements were performed. The probable cause of defect formation and destruction of the blade is established. The measured hardness values comply with the standard. А study of the chemical composition of metal blades is not revealed a deviation in the content of the main alloying elements. The results of fractographic analysis showed that the destruction caused the presence of a subsurface defect. The defect is an oxidizing shell of about 9×4 mm in size with propagation in operation to the outer surface. In operation, as a result of corrosion, static and dynamic stresses, a crack was formed in the area of the source with exit to the surface along the input edge of the blade. Non-destructive testing was performed on the remaining blades. No defects detected. On the basis of which it was decided to continue the operation of the working blades of the GTK-10-4 turbine, subject to periodic monitoring.
TO THE PROBLEM OF DIAGNOSTICS OF THE TECHNICAL STATE OF THE DISTRIBUTION NETWORKS LINES ACCORDING TO AIMS EMA DATA
Authors: Danilov M. I.
Published: January 2021

The problem of organization of monitoring and diagnosing of the technical state of a four-wire distribution electric network (DEN) by means of an automated information-measuring system of monitoring and accounting of electricity (AIMS EMA) consumed by subscribers is considered. As parameters characterizing the technical state of the DEN, the values of the active resistances of the lines (wires) in the network are taken. The indicated parameters can change significantly over time depending on the values of flowing currents, climatic factors of the external environment, as well as due to wear out of the wires. A technique of the operational identification of resistances of inter-subscriber DEN sections, which uses the data of the distribution network operating modes is proposed. Its implementation in AIMS EMA allows to monitor changes in values of their active resistances. A procedure of diagnosing lines in DEN is presented, it consists in analyzing the dynamics of active resistances values changes obtained at different points in time, and identifying the increase of the wear level of individual wires against the background of flowing currents and climatic factors. It is believed, that external influences lead to the same relative changes of parameters of all wires for the same interpersonal site. The wear diagnostic criterion is an increase of the active resistance values for individual wires with their unequal change relatively to the baseline values, which are determined during observations of the distribution network condition.
THE HIGH VOLTAGE TESTING OF DIELECTRIC COATINGS THICKNESS
Authors: Syasko V. A. , Golubev S. S. , Musikhin A. S.
Published: January 2021

The technology of applying many coatings (including paints and varnishes) involves the layering of visually indistinguishable layers that make up the coating system. However, in case of application technology violation, the number of coating layers (thickness) may not correspond to the declared. Thus, in a number of cases, it is necessary to control the number of layers of the final coating system. One of the most common methods for monitoring the continuity of coatings is the high voltages spark method of non-destructive testing. The method involves the application of a high voltage U between the electrode installed on the surface of the coating and the conductive substrate. The revealing of defect coating area provide by registering the coating breakdown. The analysis shows that the development of methods for detecting not only discontinuities, but also unacceptable thinning of dielectric coatings due to their spark breakdown, seems to be a promising direction in the development of high voltages spark testing. In relation to pulsed high voltages spark testing, the electrical mechanism of the breakdown of dielectrics based on quantum-mechanical concepts, the conditions of its occurrence, and the main relations obtained for calculating the electric strength Es and breakdown voltage Us for protective dielectric coatings are considered in detail. Comparative results of an experimental study of the proposed algorithms for calculating Es and Us, as well as methods for identifying (tolerance control) sections of paint coatings with an unacceptable minimum thickness and coating bubbles, are presented. The application of the proposed algorithms and methods will allow one hundred percent control of the continuity and unacceptable thinning of paint and varnish and similar dielectric protective coatings of the external and internal surfaces of pipelines, as well as various large area facilities.
IMPROVEMENT OF ENGINE OIL RELAXATIONAL ELECTRIC PARAMETERS MEASUREMENT SYSTEM
Authors: Makshakov E. D.
Published: January 2021

Mathematical model of the measured relaxation electric parameters of engine oil is designed. There are two subsystems of measuring conversion in the model: function of capacitance conversion and function of resistance of transition processes durations. In the result of physical realization of the model, own spurious capacitance and conductivity of mockup are experimentally determined depending on temperature in conditions with no external measurable parameters. The use of elements with optimal parameters in the circuitry of the measuring transducer minimized the influence of spurious conductivity. This made it possible to reduce the measurement error of the relaxation electric parameters of engine oils, increase the sensitivity along the resistance channel, and practically eliminate the mutual influence of both measurement channels. In addition to the measurement channels, a Brown filter is used to separate useful information from noise.
THE STUDY OF THE RELATIONSHIP OF VIBRATION PARAMETERS ACCOMPANYING VARIOUS TECHNOLOGICAL PROCESSES WITH TEMPERATURE CHANGES
Authors: Kozochkin M. P. , Zhed O. V. , Maung T. H.
Published: January 2021

Successful monitoring of technological processes using control of vibro-acoustic (VA) signals largely depends on the clarity of physical phenomena that determine the correlation between the functional parameters of the technological process and the diagnostic signs of vibration parameters. This article discusses such a relationship between vibration parameters and temperature in the core of technological processes. The experiments showed a stable pattern of changes in the parameters of VA signals with a change in the state of cutting tools in various technological processes associated with blade processing of workpieces. As such a parameter (Kf), the article considers the ratio of effective amplitudes in two frequency ranges: high-frequency and low-frequency. The most informative combination of frequency ranges is selected experimentally and depends on the dynamic characteristics of a particular elastic system. The paper gives examples of Kf changes for turning and grinding processes. To identify the nature of this phenomenon, experiments with the action of laser pulses on a steel plate with parallel recording of VA signals are considered. As a result, it is concluded that the Kf change is associated with a temperature increase in the frictional contact of the tool and the part when the cutting ability of the tool blade deteriorates. The work emphasizes that in the implementation of technological processes there are conditions that violate the described regularity. As such an example, the article shows an example of intense self-oscillations that changes the temperature regime in the contact zone. At the end of the work, it was shown that even during electric discharge machining, by changing the parameter Kf, it is possible to prevent short circuits and breaks in wire electrodes.
DEVELOPMENT OF AN APPROACH FOR ASSESSING THE HARDNESS OF COATINGS WITH DYNAMIC INDENTATION
Authors: Kashapova I. A. , Fedorov A. V. , Egorov R. A. , Ilinskiy A. V.
Published: January 2021

The article discusses the features of the method for assessing the hardness of coating materials based on the dynamic indentation approach, the essence of which is the continuous registration of the process of contact interaction of the indenter with the material under study. According to the research results, a regression dependence was obtained in the form of a polynomial of the second degree, which makes it possible to assess the hardness of a galvanic nickel coating.
ESTIMATION OF ERROR IN MEASURING THE DEPTH OF SURFACE CRACKS BY THE ELECTROPOTENTIAL METHOD ON AN ALTERNATING CURRENT
Authors: Shkatov P. N. , Kuzub I. G. , Ermolaev A. A.
Published: January 2021

The study carried out research on the error in measuring the depth of surface cracks by the electropotential method on an alternating current with a variation in the magnetic permeability and specific electrical conductivity of the metal. The measuring error appear from the difference between the electromagnetic properties of the metal of the sample used to obtain the calibration dependences and the properties of the metal of the tested object. The research conducted by the method of the finite element. The analysis of the dependences of the electropotential signal in the frequency range for the defect-free area and the area with a surface crack is carried out. The study of the error in measuring the depth h, that depends on the frequency of the transmitted current and the value of h. The comparison of the errors arising from various methods of choosing the calibration characteristics is performed, including the comparison of the equality of electropotential signals in the defect-free areas of the tested area and the test sample selected for calibration.
COMPARATIVE ASSESSMENT OF METHODS FOR PREDICTING THE TECHNICAL CONDITION OF ELECTRIC DRIVES OF HAZARDOUS PRODUCTION FACILITIES
Authors: Vasenin A. B. , Stepanov S. E. , Kryukov O. V.
Published: January 2021

The paper deals with the design of efficient and reliable systems for operational diagnostics and forecasting of the technical condition of adjustable megawatt electric drives. The statistics of failure of the most critical components of AC electrical machines – stator windings, bearings and ACS are presented. The methodology and architecture of artificial neural networks have been developed for obtaining predictive models of high-voltage synchronous machines. Examples of neuro-fuzzy prediction of the technical state and resource of stator windings and analysis of the spectral composition of the supply voltage by the series method are given. Tests of selected networks, the Box–Jenkins fuzzy model, models of the method for analyzing the dynamics of spectral components with predicting the values of current and stator temperatures are obtained. The comparative results of the analysis of the expected states of electric machines of high power, based on the consideration of various operational factors of the operation of electric drives, made it possible to develop recommendations for the use of new predictive methods.
On the Neuber theory of micropolar elasticity. A pseudotensor formulation
Authors: Kovalev Vladimir Aleksandrovich , Murashkin Eugenii Valeryevich , Radayev Yuri Nikolaevich
Published: January 2021

Рассматривается псевдотензорная формулировка теории микрополярной упругости Нейбера.
Приведены и обсуждаются динамические уравнения микрополярного континуума в терминах относительных тензоров (псевдотензоров). Даны определяющие уравнения для линейного изотропного микрополярного твердого тела. Окончательные формы динамических уравнений для изотропного микрополярного континуума в терминах смещений и микровращений получены в терминах относительных тензоров. Устранены недочеты в окончательной форме динамических уравнений Нейбера. Получены динамические уравнения Нейбера в цилиндрической системе координат.
Firm’s Innovation Ecosystem: Barriers, Key Success Factors and Strategies
Authors: Hieu Vu Minh , . .
Published: January 2021

Strategic positioning fosters the firm performance in an ecosystem. Companies in an innovation ecosystem use strategic tools to connect different business units. The systematic literature review was used to search for the articles used in this review. Google Scholar search engine was employed to filter the references of each selected paper. In total, 41 papers published in journal and conference proceedings have been used for the review. The review shows that companies challenges as shortage of willingness to share insights and intellectual property, confusion over management methods need to create sustainable value, lack of coordination within the ecosystem, lack of an innovation plan, failure to pay attention to a new set of risks and costs associated with network-types of practices when innovating through an ecosystem. The review highlights specific key success factors such as management commitment, consumer value, and value chains linked to customers’ expectations, and organisational culture that supports change processes, well-articulated goals, timelines and milestones, and embracing risk-taking and understanding the nature of risks in collaborative networks. Furthermore, the review also identified the balanced scorecard multiplying risks and value blueprint as strategic tools used to evaluate the performance of companies within an ecosystem. The study concludes that managers should evaluate the ecosystems’ ability and the potential of their firms to survive.
Multiplexed supercell metasurface design and optimization with tandem residual networks
Authors: Yeung Christopher , Tsai Ju-Ming , King Brian , Pham Benjamin , Ho David , Liang Julia , Knight Mark W. , Raman Aaswath P.
Published: January 2021

Complex nanophotonic structures hold the potential to deliver exquisitely tailored optical responses for a range of applications. Metal–insulator–metal (MIM) metasurfaces arranged in supercells, for instance, can be tailored by geometry and material choice to exhibit a variety of absorption properties and resonant wavelengths. With this flexibility, however, comes a vast space of design possibilities that classical design paradigms struggle to effectively navigate. To overcome this challenge, here, we demonstrate a tandem residual network approach to efficiently generate multiplexed supercells through inverse design. By using a training dataset with several thousand full-wave electromagnetic simulations in a design space of over three trillion possible designs, the deep learning model can accurately generate a wide range of complex supercell designs given a spectral target. Beyond inverse design, the presented approach can also be used to explore the structure–property relationships of broadband absorption and emission in such supercell configurations. Thus, this study demonstrates the feasibility of high-dimensional supercell inverse design with deep neural networks, which is applicable to complex nanophotonic structures composed of multiple subunit elements that exhibit coupling.
Synthesis and crystal structure of oktakis(dimethylsulphoxide-κ1
O)gadolinium(III) [tetrabromido-μ2-bromido-μ2-sulfido-di-μ3-sulfido-μ4-sulfido-tetracopper(I)-tungsten(VI)], C16H48O8S12Br5Cu4GdW
Authors: Ye Yunfeng , Tang Guodong , Qian Jun
Published: January 2021

C16H48O8S12Br5Cu4GdW, monoclinic, P21 (no. 4), a = 11.576(2) Å, b = 12.407(3) Å, c = 17.582(3) Å, β = 100.76(3)°, V = 2480.8(9) Å3, Z = 2, R
gt(F) = 0.0446, wR
ref(F
2) = 0.1169, T = 293 K.
Crystal structure of (E)-2-chloro-6-(((1,3-dihydroxy-2-(oxidomethyl)propan-2-yl)imino)methyl)phenolate-κ3N,O,O’)manganese(IV), C22H24Cl2MnN2O8
Authors: Xu Xindi , Wang Xia , Tian Hui , Wang Man , Wu Qiong
Published: January 2021

C22H24Cl2MnN2O8, monoclinic,C2/c(no. 15),a = 11.0944(4) Å,b = 18.2945(9) Å,c = 11.9283(5) Å,β = 114.3299(12)°,V = 2206.03(16) Å3,Z = 4,Rgt(F) = 0.0305,wRref(F2) = 0.0791,T = 150.0 K.
Enumeration of S-Motzkin paths from left to right and from right to left: a kernel method approach
Authors: Prodinger Helmut
Published: January 2021

The area of S-Motzkin paths (bijective to ternary trees) is calculated using the kernel method by enumerating these (partial) paths with fixed end-point resp. starting point.
Review on Alternatives of Aggregates with Alternative Materials in Eastern Africa
Authors: Ngandu Cornelius Ngunjiri
Published: January 2021

Normal concrete, with bulky aggregate generally results to large amount of energy and natural resource requirement. Normal aggregates mining and river sand extraction, if done in unsustainably, potentially results in adverse environmental, health or hazardous impacts. There is therefore the need to research and utilize alternative more sustainable construction materials.

This main aim is to review properties of alternative aggregate or mixes with those aggregates within Eastern Africa. In this study, 23 reviews, at optimum aggregate replacement using volcanic materials, crushed rock sand and also fired bone generally indicated good strength performance. Majority of the alternative materials mixes presented indicated higher water absorption, lower slumps/workability and density, compared with the reference. Lower slump could affect compaction, strength or increase costs. Appropriate cost-effective admixtures or plasticizers are recommended while materials exhibiting lower strengths could be explored for non-structural use. Utilization of recycled waste for aggregate could help address resource scarcity and reduce construction environmental footprint.

There should be more research and development of proper procedures and techniques so as to ensure adequate bondage, optimal water/cement ratio and compaction and also use of cost-effective admixtures.
The Effect of BI Rate, USD to IDR Exchange Rates, and Gold Price on Stock Returns Listed in the SRI KEHATI Index
Authors: Utama Oktavian Yodha , Puryandani Siti
Published: January 2021

This study aims to determine the effect of BI rate, USD to IDR exchange rates, and gold price on stock returns listed in the SRI KEHATI Index for the period January to December 2018. The population in this research is companies listed on the Indonesia Stock Exchange. The sample is determined by using a purposive sampling method. Some criteria of the sample are companies that: had entered to the SRI KEHATI index respectively from January to December 2018, reported the 2018 monthly financial report, were not suspended by the IDX during the study period, so that obtained a sample of 23 companies with total data is 268. This study used quantitative data analysis in the form of time-series data from January to December 2018. The data collection method used in this study is the documentation method. The analytical tool in this study is the multiple regression analysis. In this study, data is processed by using the SPSS program 21. The results show that the BI rate has a significant positive effect on stock returns, the USD to IDR exchange rate has a significant negative effect on stock returns, and gold price does not have a significant effect on stock returns.
Morphometry of Cortical Neurons in Acute Clozapine and Ethanol Poisoning
Authors: Bashirova A. R. , Sundukov D. V. , Babkina A. S. , Golubev M. A. , Telipov I. N.
Published: January 2021

The aim of the study is to summarize the histology and morphometry of cortical neurons in acute clozapine and ethanol poisoning.

Material and methods. Histological examination of the parietal cortical brain samples of 26 patients died during the Day 1 of acute clozapine and ethanol poisoning (23 males and 3 females aged 22-63 years) was performed. The blood ethanol level was 1.4-4.1%o. The level of clozapine in the blood ranged between 0.24 and 5.8 mg%, in the liver between 0.097 and 6.5 mg%, in kidneys between 0.03 and 3.5 mg%. The cortical samples for morphometric examination were placed in 10% neutral paraformaldehyde, the histological sections were done and stained with hematoxylin and eosin, as well as according to Niessl. The morphological analysis was performed using the video light microscopy. The number of damaged neurons (with separate quantification of reversible, intermediate, and irreversible damage) was assessed. The statistical analysis was done using the non-parametric methods.

Results. The signs of brain neuronal damage in acute clozapine and ethanol poisoning, as well as forensic chemical tests, might be used for establishing the direct cause of death.
Some open questions of evaluation of comfort properties of functional clothing
Authors: Hes Lubos
Published: January 2021

In the paper, several relatively new aspects of testing of functional clothing are discussed, such as the effect of moisture and testing time on water vapour permeability of fabrics as well as the effect of the testing time on thermal resistance value of fabrics tested in Skin Model type testers. Also the difference between thermal resistance and thermal absorptivity of fabrics was explained. It was concluded, that there are still some unsolved problems in the above areas, which should attract the attention of textile scientists and technologists.
Incidence of hereditary thrombofilies in a population of Mexican women
Authors: Víctor Manuel Vargas Hernández , Estuardo Lujan Irastorza Jesús , Jesús Ávila Pérez Felipe de , Daniela Ávila Rebollar , Maruxa Pariente Fernández Maruxa , Carlos Durand Montaño
Published: January 2021

Objective: To report the incidence of thrombophilias and importance in the development of thrombotic events in a population of Mexican women. Methods: Is a retrospective, observational and cross-sectional study of 184 women of reproductive age, where the age, weight, height and study of hereditary thrombophilias of FVL-G1691A, PT-G20210A, MTHFR-C677T and PAI-1 4G/5G were studied. Four groups were formed: 1) FVL-G1691A, 2) PT-G20210A, 3) MTHFR-C677T and 4) PAI-1 4G/5G, each group was separated by homozygous and heterozygous mutation. Results: MTHFR-C677T and PAI-1 4G/5G present higher incidence (48.9 and 64%), when comparing with FVL-G1691A and PT-G20210A (3.8 and 0.5%) (p<0.05), higher incidence of PAI-1 4G/5G was observed, when compared to MTHFR-C677T (64.6 vs. 48.9%, p<0.05), difference that was not observed when comparing FVL-G1691A with PT-G20210A (3.8 vs. 0.5%, p>0.05). When patients presented only one thrombophilia, the highest incidence is of MTHFR-C677T and PAI-1 4G>5G (16.5 and 35.2%). Patients with multiple thrombophilias had an incidence of MTHFR-C677T with PAI-1 4G/5G of 30.2%. Conclusion: Our results in the population of Mexican women, we report a high incidence of the MTHFR-C677T and PAI-1 4G / 5G mutation, which makes them susceptible to the development of thrombotic events.
Effectiveness and safety of dinoprostona and cook’s balloon for labour induction in pregnants with small for gestational age fetuses
Authors: Gómez Jorge Duro , Lucena Marta Porras , María Vendrell Aranda Celia
Published: January 2021

Objectives: To compare the effectiveness (hours until delivery) and safety (rate of vaginal deliveries and caesarean sections, use of oxytocin and perinatal outcomes) of dinoprostone and Cook's balloon as a method of labor induction in pregnant women with fetuses with an estimated weight below the 10th percentile and normal Doppler. Methods: retrospective cohort review of pregnant women with small for gestational age fetuses and induced with both methods in Reina Sofía Hospital, Cordoba, Spain from 2014 to 2018. The main outcome was time until delivery. Descriptive characteristics, obstetric and perinatal outcomes were analyzed. 322 pregnant women were induced: 204 women were induced with Cook's balloon (CB) and 118 with dinoprostone (DIN). RESULTS: Dinoprostone decreases the time until delivery (28.86 vs. 24.32 hours with CB and DIN, respectively, p<0.0001) and the use of oxytocin (79.7% vs 54.2% in CB and DIN group; p<0,01), as compared to Cook's balloon. No differences were observed in the rate of caesarean sections and vaginal deliveries, as well as in perinatal results. Conclusion: DIN reduces the time to delivery compared to CB with a lower need for oxytocin. Moreover, without worse perinatal outcomes.