Scientific journal of the Ternopil national technical university最新文献

{"title":"Comparison of solving algorithms for a mathematical model of filtration-diffusion transfer in the medium of spherical moisture-saturated microporous particles","authors":"M. Petryk, Dmytro Mykhalyk, O. Petryk","doi":"10.33108/visnyk_tntu2021.01.015","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.01.015","url":null,"abstract":"The article considers the use an analytical and numerical approaches for finding solutions of mathematical model of diffusion mass transfer in the medium of particles of microporous structure. The special software developed based on both approaches and these software were used for computer simulation of pressures in particles and interparticle space for spatial and temporal parameters of the filtration process, and the results were compared taking into account their accuracy and speed of production. Considered algorithms showed approximately the same accuracy in finding the pressure profiles. Analytical solution-based software has demonstrated the higher efficiency for calculating unit pressure values at given parameters, in turn, numerical techniques have been found to be convenient for building high-resolution profiles.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82161946","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":"Numerical simulation of dynamic shear tests for high-strength steels specimens","authors":"Ievhen Kondriakov, V. Kharchenko","doi":"10.33108/visnyk_tntu2021.02.110","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.02.110","url":null,"abstract":"A series of numerical calculations using the finite element method was carried out to develop a dynamic shear testing method for high-strength steels specimens. The shape of the specimens with two shear zones was chosen for investigations. Obtained results made it possible to choose the optimal specimen size and loading scheme for realizing pure shear conditions. Using the Johnson-Cook model, taking into account the effect of the strain rate, the fracture of the specimens of armored steel Armox 500T was simulated using the appropriate fracture criterion. Obtained results showed that such a specimen design and loading scheme should ensure the implementation of pure shear conditions.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82215634","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":"Substantiation of flexible screw conveyor metal consumption under productivity maintenance conditions","authors":"T. Dovbush, A. Dovbush, Nadiia Khomyk, H. Tson","doi":"10.33108/visnyk_tntu2021.03.033","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.03.033","url":null,"abstract":"Transportation, as well as loading and unloading, of bulk materials by flexible screw conveyors has wide practical application and its share is approximately 40–45%. The flexible screw conveyors are also widely used as they can change the trajectory and height of technological raw material transportation. The above-mentioned mechanisms consist of separate rigid sections which are pivotally connected between each other. Though, high metal consumption is one of their disadvantages. Taking into account that the load on section is increasing from the unloading area to the working body, it has enabled us to reduce their metal consumption.Some theoretical substantiation of productivity determination and energy values of flexible screw conveyors depending on the type of technological raw material and the height of transportation has been given in the article under discussion. The obtained characteristics have made possible to substantiate the force factors acting on separate sections. The rigid sections where the rotary moment transmission is taking place due to the flat plates action have been used in the flexible screw conveyor. Therefore, some recommendations on the mechanism metal consumption reduction without its productivity decrease due to the plates size optimization have been made in the article under discussion.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81560355","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":"Features of pressing the juice from viburnum berries","authors":"Mariia Shynkaryk, O. Kravets, Stepan Venhrynovych","doi":"10.33108/visnyk_tntu2021.01.094","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.01.094","url":null,"abstract":"The article is devoted to the investigation of the process of pressing the juice from viburnum berries. The yield of juice from berries according to the data is approximately 60–65%. However, due to the small amount of processing, as well as specific properties, the investigation of individual technological processes is not given enough attention. The peculiarity of viburnum is the presence of heart-shaped grains, which in the juice bring bitterness. In the process of pressing it is important to create the pressure optimal for it. In order to establish the process modes, the investigations of the compression and filtration characteristics of viburnum berries are carried out. According to the investigation results, rational technological parameters and modes of equipment operation are proposed. Rational values of the height of the product layer in the process of juice removal and the pressure of the pressing process are established.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81036944","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":"Use of p -adic numbers in urban resource networks data analysis","authors":"Oleksandr Matsiuk","doi":"10.33108/visnyk_tntu2021.04.058","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.04.058","url":null,"abstract":"The implementation of the concept «smart city» has required, in particular, the development and efficient use of new mathematical methods and approaches enabling the data hypercube analysis to be made efficiently and constructively, data transfer processes to be initiated, etc.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"420 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87876182","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":"Calculation of electric potentials on the surfaces of interaction of deformable metal bodies with hydrogen-containing environment","authors":"M. Stashchuk, P. Pukach, E. Irza, R. Hromyak, Nazar Stashchuk","doi":"10.33108/visnyk_tntu2021.04.098","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.04.098","url":null,"abstract":"In most cases the metal structures service under operating conditions results in the fact that these structures or their certain elements are constantly affected not only by mechanical factors (load, residual stresses, etc.), but also by the environment. Elements of pipelines, load-bearing sections of thermal and hydroelectric power stations, metal structures of bridges are all influenced by the environment that fills or surrounds them. Such environment depending on the content of acids and alkalis, a number of hydrogen-containing media can be corrosive. It should be also noted that the influence of such corrosive environment and mechanical factors influence are simultaneous and interrelated resulting very often in brittle or quasi-brittle metal fracture. Therefore, the problem of estimating the basic metal structures engineering parameters (strength, reliability, etc.) that are corroded by the simultaneous action of mechanical force factors, is currently an important problem of industrial operation. The paper presents problems based on the theory of elasticity, electrodynamics, theoretical electrochemistry and equations of mathematical physics. According to the established analytical ratios for the calculations of effective electric potentials and the corresponding numerical experiments, the estimation of electric potentials on the surfaces of interaction of deformable metal bodies with hydrogen-containing medium is carried out.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"11 s1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91427291","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 a web resource for safe job search in a Covid-19 pandemic","authors":"A. Boichuk, T. Styslo, S. Vashchyshak, Petro Ostafiichuk","doi":"10.33108/visnyk_tntu2021.03.123","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.03.123","url":null,"abstract":"The work describes the main steps, the structure, and the result of web resource for job search, which is relevant in the context of a pandemic and employment loss of a large number of citizens. The focus is on the development of a platform with enhanced protection from the point of view of a job seeker, who can analyze data about the employer, and leave a real feedback both at the job search stage and after employment. For this purpose different user profiles and a real opportunity to leave feedback are provided. A platform is developed using PHP with PDO extension for database connection. MySQL relational database is used as a database. All phases of resource development, from architectural and database planning to the development of layouts and interfaces, are described in details. Special attention to the protection of information transmitted by both employers and job seekers is paid. The functionality of the developed system is analyzed. The received resource has been tested and it has been established that it can be used effectively for both employers and job seekers with the appropriate functionality, the ability to post, edit, delete vacancies and comments about the company. This, in turn, makes it possible to avoid fraud and cybercrime by checking the veracity of the information provided by the employer and forming an employer’s rating based on real feedback from persons who work or have worked there.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90616126","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":"Investigation of object manipulation positioning accuracy by bernoulli gripping devices in robotic cells","authors":"V. Savkiv, Roman Mykhailyshyn, Vadim Piscio, Ihor Kozbur, F. Duchoň, Lubos Chovanec","doi":"10.33108/visnyk_tntu2021.02.021","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.02.021","url":null,"abstract":"Ensuring the necessary accuracy of positioning the objects of manipulation of Bernoulli's grippers in robotic cells is an urgent task and can be achieved by choosing rational parameters of the gripping process. The article conducts experimental studies of the process of handling by Bernoulli grippers of objects of manipulation at different operating parameters and their weight. For this purpose, an experimental setup was developed, which consists of an industrial robot IRB 4600, an IRC5 controller, a Raspberry Pi microcontroller and two clock-type micrometers. The method of determining the total positioning error of the \"robot-gripper-object\" system is presented, which takes into account the positioning errors of the industrial robot, the errors of the gripping device and the errors of basing the object of manipulation relative to the axis of symmetry of the gripping device. The ABB IRB 1600 industrial robot was programmed in the ABB RobotStudio environment to cyclically simulate the handling operation and to determine the deviation of the position of the manipulation object after its gripping from different distances. The first cycle of automatic mode was used to calibrate the micrometer indicators, while gripping the object was carried out from a distance of 0.02 mm. For better reliability of research results, 20 measurement cycles were performed for each of the variable parameters. As a result, it was found that the maximum base error of objects does not exceed 0.4 mm. When capturing objects from a distance of 0.5…1 mm, the mean value of the base error will be 0.08…0.15 mm, with a standard deviation of 0.025…0.035 mm. The paper studies the effect of the displacement Δ of the center of mass of the gripped object relative to the axis of the Bernoulli gripper on the accuracy of the base of the objects. It is established that when the center of mass of the gripped objects is shifted relative to the Bernoulli gripper axis up to 20 mm, the maximum base error of the objects increases 2.2 times.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73083389","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":"Mathematical fundamentals of the method of identification of metal inclusions in raw materials with automatic determination of their coordinates","authors":"L. Zamikhovskyi, Ivan Levitskyi, Mykola Nykolaychuk, Yuriy Striletskyi","doi":"10.33108/visnyk_tntu2021.03.023","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.03.023","url":null,"abstract":"The article deals with the actual problem of theoretical substantiation of the method of identification (diagnosis) of metal inclusions (hereinafter referred to as metal inclusions) in bulk raw materials under the conditions of a conveyor belt. The presence of metal inclusions in the raw material transported by the conveyor belt can lead to both emergencies and deterioration in the quality of the output product. The identification method provides for diagnosing the presence of metal inclusions, determining its dimensions, type of metal and coordinates relative to the cross-section of the conveyor belt. The results of theoretical and experimental studies of the method for identifying metal inclusions based on a scanning signal and an additional excitation coil are considered. A mathematical model has been developed for determining the position of metal inclusions on a conveyor belt relative to a line perpendicular to the axis between two excitation coils, including two trajectories for determining coordinates for three excitation coils and two receiving coils.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79221639","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":"Mathematical model of functioning of the srew conveyor loading hopper","authors":"Viktor Baranovskyi, V. Pankiv, Roman Komar, Bohdan Berezhenko, O. Korol","doi":"10.33108/visnyk_tntu2021.04.109","DOIUrl":"https://doi.org/10.33108/visnyk_tntu2021.04.109","url":null,"abstract":"Increasing productivity and reducing energy costs of the process of operation of screw devices and technological lines of processing complexes, where they are installed in agricultural sector, in the first stage depends mainly on the throughput capacity of loading hoppers. At the same time, the need for rational management of the flows, that have quite significant random deviations from the measure of average of the root crops flow, is quite an urgent task. The objective of investigation is to increase the efficiency of screw conveyor-crushers by developing a mathematical model which functionally describes the technological process of movement of the material in the loading hopper. The article provides an analysis of the process root crops movement in the screw conveyor loading hopper through the development of deterministic mathematical models that describe and determine the quantitative indicators of per second feeding of root crops to the auger depending on the hopper loading.","PeriodicalId":21595,"journal":{"name":"Scientific journal of the Ternopil national technical university","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77038174","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}