Science & Technique最新文献

{"title":"Corrosion – Biotechnical System for Destruction of Technical Objects Reducing their Quality and Reliability","authors":"A. Kudina, I. O. Sokorov","doi":"10.21122/2227-1031-2020-19-6-512-520","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-6-512-520","url":null,"abstract":"It is a well-known fact, that corrosion of materials, as a phenomenon in the nature, is multifaceted, where its origin and development in many respects depend on environment micro-flora. In the modern world, corrosion is considered mainly as the spontaneous destruction of solids caused by chemical and electrochemical processes, developing on a body surface during its  interaction  with external environment.  The essence  of  corrosion  destruction   of objects  should be studied in aspect  of  the interrelated natural phenomena and processes that constantly occur  when an  object comes into contact with man-made environments and the environment containing many microorganisms of various genera and species. The accumulation and metabolism of microorganisms in surface defects of solids, when favorable physical, chemical and biological conditions are created in the contact zones, create areas of biocenosis in which metabolites, biogenic elements and chemically active radicals are formed, interacting with the contact surface of the body and the technogenic environment. Such interaction gives rise to the occurrence of both biochemical reactions in microbial cells and bioenergetic mechanisms of energy conversion on the contact surfaces, both in the microorganisms themselves and in the surrounding space. This initiator chemical, electrochemical and bio-corrosion processes of materials destruction. Consequently, the phenomenon of corrosion is presented as a system of interrelated microbiological and physicochemical processes of destruction of materials, arising from their interaction with the micro-flora of contact technogenic media and the environment. Based on the generalization and analysis of the results of the performed research work and taking into account the well known achievements and discoveries in the field of science and technology, the authors of the paper propose a new systematic approach and concept to the phenomenon of corrosive destruction of a solid with the account of the biological factor that initiates corrosion damage and destruction of materials.","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"12 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88385270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plastic Deformation and Electrophysicochemical Treatment of Tubular Medical Concentrator Waveguides","authors":"Dai Wenqi, Y. Aliakseyeu, A. Korolyov, A. S. Budnitskiy","doi":"10.21122/2227-1031-2020-19-6-499-506","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-6-499-506","url":null,"abstract":"Ultrasonic methods for eliminating vascular obstruction are widespread throughout the world. The advantages of such methods are the absence of surgical intervention, a low probability of complications, and a low cost of treatment. Ultrasonic waveguide systems for the destruction of intravascular formations and elimination of vessel obstruction are made in the form of hollow or continuous long rods of constant and variable cross-section (concentrator waveguides). The development of new methods of treatment based on the use of stepped ultrasonic waveguide systems of a tubular type is underway, Адрес для переписки Будницкий Алексей Сергеевич Белорусский национальный технический университет ул. Я. Коласа, 24, 220013, г. Минск, Республика Беларусь Тел.: +375 17 292-76-78 budnitskiy@park.bntu.by Address for correspondence Budnitskiy Alexey S. Belarusian National Technical University 24, Ya. Kolasa str., 220013, Minsk, Republic of Belarus Tel.: +375 17 292-76-78 budnitskiy@park.bntu.by","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"29 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77939483","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Technological Features in Processing of Conical Lenses","authors":"M. Filonova, R. O. Dias Gonzalez, A. A. Sukhotzkiy, A. S. Kozeruk, A. V. Semchuonok","doi":"10.21122/2227-1031-2020-19-6-521-527","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-6-521-527","url":null,"abstract":"The paper presents the technology of obtaining flat-conical lenses (axicons) by the method of free grinding a work-piece to a flat tool through a layer of abrasive suspension. For this, theoretical and experimental studies of the regularities of stock removal from the base of the cone and its lateral surface have been carried out. The processing modes have been identified that ensure both uniform operation of the flat surface of  the part and enhanced removal of  the allowance in the edge or central zone of this surface. During the study of the processing of the conical surface, the set-up parameters of the technological equipment have been established, at which there is a minimum deviation of the generatrix of the cone from straightness and maximum productivity of the process. The stages of processing conical lenses are proposed, which allow to assign the optimal sequence of operations in the manufacture of this type of parts from blanks of a cylindrical shape in cases where  the ratio of the height of the cone to the diameter of its base H/d £ 0.5. The main stages of processing include: grinding of the bases of cylindrical blanks with maintaining their mutual parallelism with a given accuracy; polishing one of the cylinder bases to achieve the required roughness and deviation from non-flatness; fastening a cylindrical blank to an auxiliary plane-parallel glass plate using molecular cohesion forces; mechanical fastening of a cylindrical work-piece with a collet adapter mandrel for a plane-parallel glass plate; applying the nearest sphere to the second base of the cylindrical blank; drawing a conical surface on the spherical part of a plano-convex lens; grinding and polishing the conical surface to achieve the required roughness  and straightness of the cone generatrix. The degree of efficiency of the setup parameters of the machine has been revealed depending on the technological heredity of the work-piece from the point of view of the distribution of the allowance to be removed over the machined surface. ","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"8 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73968827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Research of Technology for Strengthening Reinforced Concrete Columns with Carbon Fibers","authors":"O. Molodid","doi":"10.21122/2227-1031-2020-19-5-395-399","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-5-395-399","url":null,"abstract":"Reinforcement of columns (piers) is usually accomplished by increasing cross-section through building-up, injecting reinforcing solutions and external reinforcement. The most and progressive method for strengthening is currently external reinforcement, its essence is to glue high-strength sheets, plates or strips (lamellas) onto structure surface with the help of special adhesives. Scientists pay special attention to theoretical and experimental studies of design solutions for external reinforcement of vertical load-bearing structures. Unfortunately, the results of such studies, for example, influence of technology for execution of works on strengthening efficiency are virtually absent. Therefore, the objective of this paper is to carry out experiments with the purpose to study influence of technological factors on efficiency in strengthening of reinforced concrete structures, which absorb compressive forces. The experimental studies have been made in six series that changed the technology of executed works while using various technological factors. Among the main factors are the following: presence/absence of acute angles; preparation of a base (surface coating); method for gluing reinforcing materials to a structure. A criterion for evaluation of technology efficiency has been breaking strength for axial compression of reinforced samples. Адрес для переписки Молодед Александр Станиславович Киевский национальный университет строительства и архитектуры просп. Воздухофлотский, 31, 03037, г. Киев, Украина Тел.: +380 67 306-73-59 molodid2005@ukr.net Address for correspondence Molodid Oleksandr S. Kyiv National University of Construction and Architecture 31, Povitroflotsky Ave., 03037, Kyiv, Ukraine Tel.: +380 67 306-73-59 molodid2005@ukr.net","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"8 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75357717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intelligent Model of Potential Risks in Emergence of Man-Made Disaster","authors":"A. Gulay, V. Zaitsev","doi":"10.21122/2227-1031-2020-19-5-437-448","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-5-437-448","url":null,"abstract":"A man-made catastrophe is considered as an information display of catastrophic development of events in the management system, a peculiar projection of  a man-made catastrophe on the information plane. The paper presents an intellectual model, considers dynamics and ranges of emergency changes in management system parameters, assesses potential risks and  threats  of  catastrophe  emergence.  It  has been  shown  that  at  the  macro-structural  level  for  semantic   description of a catastrophe, it is quite effective to use a tree-like network of scenarios, which displays the conceptual scheme of the subject and problem areas of the catastrophe and is based on judgments of experts, their experience and intuition. This allows probabilistic methods  to  assess  potential  risks  of  a catastrophe using two quantitative indicators: risk (probability) level of  phenomenon occurrence at a certain control point of time and the volume of the expected material loss. It has been suggested that for assessment of possible microstate the fuzzy logic should be applied for each critical object parameter, tolerance limits and functions of affiliation with the fields of fail-safe object functioning should be set by expertise, migration trajectories of relative parameter values should be monitored and terms of their forced return to the working field of regular functioning should be duly provided. Quantitative indicators having imprecise origin have been introduced in the intelligent model of potential risks to assess dynamics of catastrophe threat. One of these indicators is the expert level of catastrophe occurrence during migration of a group of abnormally dangerous parameters of a technical object. The time interval has also been considered which is measured from the current moment to the expected moment of catastrophe occurrence at the preset maximum permissible level of catastrophe threat.","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"58 2","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72537650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cartographic Extrapolation as Method for Forecasting Natural Phenomena and Processes","authors":"V. I. Mikhailov, E. Y. Myslivchi","doi":"10.21122/2227-1031-2020-19-5-407-412","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-5-407-412","url":null,"abstract":"All known forecasting methods cannot do without the help of maps when it comes to natural phenomena and processes. Geographic forecasting can be considered as predicting geographic phenomena or processes that cannot  be explored. Identity of the methodology for forecasting the dynamics of phenomena in time and their propagation in space makes it possible to transfer the patterns that are true for time sequences to spatial series. In contrast to specialized forecasting methods developed by individual sciences, cartography provides a researcher with a general forecasting method called cartographic extrapolation. In this case the extrapolation is understood as the spread of patterns obtained in the course of cartographic analysis of  a  phenomenon  or  a  process to an unexplored part of  this  phenomenon or process to another territory, for the future. The foregoing is considered on the example of a map of Modern vertical movements of the Earth’s crust in the Republic of Belarus which is compiled according to geophysical data and repeated leveling. Predictive patterns and expectations are highlighted while applying the method of cartographic extrapolation on the map. The efficiency of cartographic extrapolation is increased with the complex use of different methods. The interaction of cartographic and remote methods is of particular importance. Joint analysis of maps, aerial and satellite images obtained from different heights and in different ranges helps to predict general global, regional or local patterns. An example of this is geological and geomorphological research. Maps of different contents and the results of interpretation of aerial photographs have been used to predict the neo-tectonic structure of the territory in the zone of junction of the Mikashevich ledge of the crystalline basement and the Turov depression in the Belarusian Polesie.","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"21 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73486148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Method for Determining Elements of Internal Orientation Calibration in Multi-Matrix Optoelectronic Devices","authors":"M. A. Starasotnikau, I. V. Padskrebkin, R. V. Feodortsau","doi":"10.21122/2227-1031-2020-19-5-428-436","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-5-428-436","url":null,"abstract":"In the operation schemes of optical electronic devices (OED), such as digital autocollimators, direction finders, Shack-Hartmann sensors, as well as astro-orientation systems, projection measuring systems, geometric calibration schemes for OED, the photo-detector acts not only as a receiving device, but also as a measuring device. The tasks facing the OED photo-detectors. The solution to the problem is the use of several photo-detectors installed on one electronic board. Since OED photo-detectors act, inter alia, as measuring devices, it is necessary to perform their geometric calibration. Geometric calibration involves the measurement of interior orientation parameters used in the processing of OED images. Geometric calibration makes it possible to eliminate errors in mutual exposure of photo-detectors on one electronic board installed in the focal plane, as well as distortions introduced by the OED lens, primarily by distortion. The correctness of the interior orientation parameter determination is influenced by the relative position of the collimator, with the help of which the geometric calibration is performed, and the calibrated OED itself, i. e. the external orientation elements. The task is to separate the interior orientation parameters and the elements of external orientation. This is achieved using the method of mathematical processing of measured data in the forward and inverted positions of the collimator. This method of geometric calibration allows to use it for geometric calibration of OED with a large number of photo-detectors. The paper presents the results of the geometric calibration of the interior orientation parameters when the collimator projects a test object onto three photo-detectors of the OED layout. The factors influencing on the accuracy of the geometric calibration of the interior orientation elements for OED are determined in the paper. The developed method for geometric calibration of the interior orientation parameters for multi-matrix OED provides high measurement accuracy – not more than 0.1''–0.2''.","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"2 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84320567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of Calculation Theory for Hinged-Connected Beams on Elastic Base","authors":"O. Kozunova","doi":"10.21122/2227-1031-2020-19-5-389-394","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-5-389-394","url":null,"abstract":"The paper provides a brief review of the literature on the theory and methods of calculating hinged-connected or articulated structures on an elastic base. The author refers to the works of B. G. Korenev, G. Ya. Popov, I. A. Simvulidi, R. V. Serebryany, A. G. Yuriev, in which, using various approaches, studies have been carried out to calculate hinged-connected beams and slabs on an elastic base. From the analysis of  scientific literature on the topic under consideration, it can be concluded that there is no general approach to solving this problem, which is valid for any hinged-connected beams and plates lying on any model of an elastic base under the action of an arbitrary external load.  In addition, a similar problem for this type of engineering calculations is observed in the normative documents. In the Republic of Belarus, a number of industry documents have been used to calculate pavement bearing elements for various highways and track transverse structures, in which road pavements with a load-bearing element and the connection of elements between themselves (hinged or rigid) are considered in an incoherent formulation. The paper proposes a universal approach for calculating hinged-connected beams on an elastic foundation, based on the mixed method of structural mechanics, taking into account the Zhemochkin ratios for functions of the elastic medium effects. The following hypotheses and assumptions are taken into account: only normal stresses act on  the  contact  of  the  beam  with the base, hypotheses  of  the bending  theory are valid  for beams,  hinges  between  the beams are cylindrical, and the distribution of contact stresses along the width of the beams is uniform. As a result of the proposed calculation, the stress-strain state of a system of hinged-connected beams on an elastic foundation has been investigated, namely: distribution of contact stresses under beams, internal forces in the beams and hinged joints, as well as settlements of the elastic foundation under them. The numerical implementation of this approach has been performed using the mathematical package Mathematica 10.4. Examples of calculation are given for different versions of hinged-connected beams and an elastic base: for three hinged-connected beams based on Winkler and seven – on an elastic half-space.","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"15 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86337421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Consumption of Solid Runoff during Erosion of Bottom Slope of Soil Dam","authors":"P. M. Bohaslauchyk, V. Evdokimov","doi":"10.21122/2227-1031-2020-19-5-384-388","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-5-384-388","url":null,"abstract":"Erosion is divided into two stages in accordance with the accepted design scheme for erosion of a soil dam during overflow. The paper deals with the first stage, when the downstream thrust prism is washed out. The key factor in calculating erosion deformations is the choice of the solid flow rate formula. Studies show that the mechanism of formation and transportation of solid runoff during erosion of dam models from sandy oils is very similar to that previously described by many authors for the condition of river channel erosion. The peculiarity of the process is that the erosion occurs at high speeds. Therefore, solid runoff almost immediately goes into a suspended state. To select the required formula, experiments have been carried out on models of dams made of sandy soils having various granulometric composition. It has been established that at high velocities under the considered conditions, the value of the solid waste flow rate depends solely on hydraulic characteristics of the flow. The influence of physical and mechanical properties of the eroded soil on the value of the flow rate of solid runoff is insignificant, and they may not be taken into account. Calculations have been carried out using formulas known from river hydraulics, which show that none of them gives sufficient convergence with experimental data. Based on the analysis of a large number of experimental data, a formula for the discharge of solid runoff for erosion conditions of dam models during overflow has been obtained in the paper. This has taken into account the fact that the dam erosion by the overflow has a high degree of stochasticity and is difficult to describe theoretically. This is especially evident in conditions of spatial erosion, when, simultaneously with the classical erosion of the bottom, the sides of the eroded hole periodically collapse, which is difficult to take into account in the calculations.","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"63 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90114134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electronic Lexicography: Traditional and Modern Approaches М. V. Маkarych1), Yu. B. Popova1), M. O. Shved2)","authors":"M. V. Маkarych, Y. Popova, M. O. Shved","doi":"10.21122/2227-1031-2020-19-5-421-427","DOIUrl":"https://doi.org/10.21122/2227-1031-2020-19-5-421-427","url":null,"abstract":"Nowadays there are a lot of modern technologies in electronic lexicography: speech synthesis technology, cross-referencing between dictionary modules, spell-checking functions, etc. The increasing availability of online information has necessitated intensive research in the area of automatic text summarization within the Natural Language Processing community. Belarusian scientists are also interested in this sphere and new lexicographical approaches for creating a linguistic database are shown in the paper. The authors present English-Belarusian-Russian electronic dictionary TechLex. This is the project of the 2nd English Department and the Department of Software for Information Systems and Technologies of the Belarusian National Technical University. The linguistic database of the dictionary is compiled not by the traditional method of processing a large number of paper dictionaries and combining the received translations, but by sequential processing of scientific and technical English-language periodicals. While the designing the dictionary the authors have taken into account the analysis of modern electronic multilingual translation dictionaries and created a client-server application in the Java programming language. The client part of the system contains a mobile application for the Android operating system, which has been tested on tablets and smartphones with different screen diagonals. The interface of the TechLex dictionary is designed taking into account the possibility of adding new subject areas and filling them with appropriate lexical material. The main advantage of our dictionary is that it is the first technical multilingual electronic dictionary having a Belarusian version. ","PeriodicalId":42375,"journal":{"name":"Science & Technique","volume":"45 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2020-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84626788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}