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The aim of the publication is to design an analytical relationship for determining the bending coefficient measurable by belt friction. Following the results of the presented measurements, the theoretical assumption is verified that in the material of the belt stress arises during the friction of the contact surfaces, due to external forces and bending of the belt. Selected experiments of drawing a polypropylene belt at a constant speed over an aluminium cylindrical surface are carried out using a servo drive on a measuring bench with computer-controlled instrumentation. The results of friction and bending coefficient measurements are interpreted in connection with the setting of various input parameters (especially friction surfaces and belt thicknesses), at a constant shaft speed. The newly identified dimensionless bending coefficient of belt friction is a material coefficient with a comparative information value concerning the flexibility of the belt, suitably supplementing the friction Euler-Eytelwein coefficient. The presented publication can be suitably applied especially to the engineering educational process.

The paper presents the possibility of using machine vision in the industrial area. The case study is oriented to indirect image processing in a robotic cell using a Matlab tool. Theoretical part of the contribution is devoted to the comparative analysis of various methods of the object detection and recognition. Analysis of the functionality, speed, performance and reliability of selected methods in the object detection and recognition area is processed. In the practical part, a method of implementing an indirect machine vision is designed to control the handling of objects detected and recognized on the basis of an operator requirement. Based on the analysis of the sample robotic workplace and the identified limitations, possibility of using the indirect computer vision is suggested. In such a case, the image of the workspace scene is saved on the storage and then processed by an external element. The processing result is further distributed in a defined form by a selected channel to the control component of the production cell.

The paper presents an evaluation of the combined relative uncertainty of the result of direct step temperature measurements aimed at evaluation of the indirect measurements of the specific thermal capacity of the heat insulating concrete by means of a pair of resistive cable thermometers fitted with Pt100 temperature sensors and integrated into a computer-controlled calorimetric chamber. In particular, it is a proposal of evaluation of the overall relative uncertainty of the measurement of partial temperatures measured in equidistant time steps, in a relatively wider time interval. In practice, the uncertainty of the result of step temperature measurements is most often declared only by the instrument uncertainty specified by the manufacturer. The exact evaluation of the result of the measurements of thermal and temperature material parameters measured by the calorimetric comparison method is required by the fact that the investigated samples are made of newly designed non-tabulated building materials and that the measurements are made by a prototype device.

This article discusses the impact of a lockdown caused by the novel coronavirus disease 2019 on the educational process at a selected faculty of a public university in the Czech Republic focused on economic education. The aim was to capture relevant aspects in the context of impacts on the management of the educational process in the organization. The unique situation brought the possibility of analyzing the flexibility of the organization, its ability to adapt. A questionnaire survey was conducted among academics. We found out how they coped with this situation, their technical equipment, support from the faculty, and whether they encountered any problems. The goal of the article was not to bring an exact evaluation of selected questions, but to show the state of the actual situation, to point out possible problems of users, and to link these things with the approach to the management of the organization. Based on the analysis, we bring suggestions and recommendations for improving the process of transition to online learning as well as distance education management and recommendation to support teaching, regardless of the teacher's workplace. The basic areas and activities that need to be managed were also identified. Web of Science 12 2 art. no. 75

The article describes approaches to the system of data accumulation and storage. The analysis of the possibility of accumulation and processing of data on the local server, as well as in the cloud. The study of the dependence of file transfer time on buffer size for cloud computing and processing technology has been carried out.

The paper aims to present a new method measuring the belt friction coefficient by the original computer-controlled measuring set. The essential elements of this semi-automated assembly are a digital force gauge and a digital servomotor. The Dynamixel MX64T servomotor with the externally installed shaft is a reliable, accurate and affordable instrument for examining frictional force and the belt friction coefficient, in dependence on the set constant rotational speed of the shaft. The new measurement method is realized by a double arrangement of the measuring assembly by winding the fibre onto the roller surface of the external shaft of the digital servo-motor and pulling the fibre over the external roller surface by the digital servomotor. The paper is intended for accurate engineering measurements or university scientific-research measurements, especially when it is necessary to declare the coefficients of unknown combinations of contacting materials of fibre and the roller surface, or the need to explore the properties of new types of fibres. The view of the tribological issues is physical-technical because virtually the relationships between the coupled physical phenomena of the same measuring set and the influences of the parameters of the sophisticated technical equipment on these phenomena are used.

In this article we describe the teaching of automation and informatics at the Faculty of Mining and Geology that primarily educates professionals in the field of geology and resource industries. Even in mining, the need for specializations in automation and IT has arisen in the past and, for this reason, these fields of study have been created. We also operate our branch office in Most, where part of the lessons is realized via videoconference, which has its plus and minus. We describe the problems we have with the lessons, deficiencies in study plans, and suggestions for further development. At the end of the paper, we present some of our research projects and areas of action - information systems for coal preparation plants, brownfields revitalization projects database, landscape modeling and visualization system, application of RFID technology, methane flow modeling or fault tolerant systems designing.

The paper is intended for engineer laboratory teaching and measurements in production engineering. The aim is a new method of measuring using the semi-automated measuring set and presenting the results of static shear friction coefficients and kinetic shear friction coefficients, depending on the relatively low speeds of the uniform translational movement of the body. In the framework of a specific engineering task, the methodological questions concerning the interpretation of measurement results in the context of engineering physics and its teaching are solved. Keywords –Shear friction coefficient, intelligent drive.

RWE a.s. (Joint Stock Company, formerly known as Transgas) is a main gas supplier in the Czech Republic. The company has six underground gas storages in different arreas of the country to ensure stable supply of gas. This paper describes monitori ng and balance evaluation of gas flow in RWE Underground Gas Storage Třanovice (North Moravia, the Czech Republic).

Underground coal mine environment is an environment with dynamic manifestations of methane. In this environment it is quite difficult to control various technological processes occurring therein. The technological process of collapse preventing inertisation is carried out by supply of compressed nitrogen to areas at risk of spontaneous combustion of coal. Petri nets allow the modelling of parallel dynamic systems and systems with discrete time. In conjunction with the software HPSim or WinPeSim, the individual processes can be modelled and then the results processed using a spreadsheet (Excel). Based on the results of the performed simulations, it is then much easier to determine the optimal solution or decision. Abstrakt Prostředi uhelneho hlubinneho dolu je prostředi s dynamickými projevy výskytu metanu. Takoveto prostředi je poměrně složite pro řizeni jednotlivých technologických procesů, ktere se v něm vyskytuji. Technologický proces preventivni inertizace zavalu se provadi přivodem stlaceneho dusiku do oblasti s rizikem vzniku samovzniceni uhli. Petriho sitě umožňuji modelovani paralelnich dynamických systemů a systemů s diskretnim casem. Ve spojeni se softwarem HPSim, popř. WinPeSim lze jednotlive procesy modelovat a nasledně výsledky zpracovat pomoci tabulkoveho procesoru. Na zakladě výsledků provedených simulaci lze pak mnohem snaze urcit optimalni řeseni ci rozhodnuti.

Every company and institution faces the necessity to manage its inventory. For high accuracy, security and easy operation of inventory management system it is necessary to have an easily recognizable identifier on all managed objects. The aim of our present project is to modernize the methods of automatic inventory management and asset protection with the help of the application of radio frequency identification technology (RFID hereinafter) to automatically identify the occurrence of marked objects. During the solutions we have to deal with many obstacles such as the bindings of data flowing from RFID system with internal information systems of asset owner companies. Appropriate choice of tags for individual subjects, their testing and readability experiments also have to be done. Another important part of the solution, that has to be developed in the project, is the system of reading gates. The gates are integrated in the door frames to allow automated identification of the objects brought in and out of the selected room. By modifying of mentioned solution we also introduce the design of a gatehouse that is able to prevent theft or unauthorized take away of material and equipment. In contrast, when the permitted items are taken away the system can easily generate the necessary forms to manage status of selected objects, decreasing the administrative burden. The result of the project is a solution consisting of information system and described hardware components for inventory management. The information system is possible to integrate with corporate ERP information systems. The pilot project was implemented and tested at VSB laboratories and we suppose deployment of the system in close future in cooperation with TINT Ltd. Company.

Technological processes in the raw material industry often operate continuously and requirements for high robustness and fail safe operation of the information and control systems are defined for them to fall into the fault-tolerant category. A critical element of fault-tolerant solutions ensures the continuity of data in databases. Data on the course of technological processes assume the nature he of a time series, and in the event of failure, can be attributed to a lack of data distortion in the calculation of trends, trailing averages and calculation balance evaluation. We tested the database mirroring technology in most common database systems (Microsoft SQL Server, MySQL and InterSystems Cache) in the low-price Standard category. The paper elaborates on the results of our testing and provides recommendations as to the use of database mirroring technology in information system solutions for continuous production processes.

The paper analyzes data measured by monitoring equipment prototype designed for measuring mine gas properties. The data covers measurements obtained during the first months after deployment of the monitoring equipment. The system measures CH 4 , CO 2 and O 2 concentrations, and also the speed and volume of the exhausted mine gas. The analysis of the measured data focuses on finding dependencies between variables and thus on finding possibilities for predicting and conditioning the behavior of mine gases. This analysis will also serve to identify and verify safety issues concerning the deployment of new monitoring devices based on the present prototype.

The article informs about best practices for the development of database of brownfield revitalization projects created based on experience in implementing database during the solution of the European Union project “COBRAMAN”. At the beginning there is a brief introduction into Cobraman project. Criteria that have a decisive influence on the data structure and also the recommendations for a user interface and for presentation of information are described. The article explains what should be done and what data must be available so that the developed database may form a starting structural element for modeling in the area of information systems for landscape restoration and for developing an expert system also. Expert system would be able, in accordance with the knowledge base and analogies with already realized successful as well as unsuccessful revitalization projects, recommend the most suitable project and solution for specialists and project managers concerned with revitalization projects.

The paper deals with fault tolerant information systems in raw material industry. Database is a heart of every information (control) system. To store the system in the category of fault tolerant (or disaster tolerant) systems, the goal is to solve the database continuity. Current database systems offer technology for online data mirroring. The paper brings details about solution of database mirroring using Microsoft SQL Server, with practical experiences on real projects.

The paper deals with quality control in the production of coal and coke in OKD, a. s., which is the main producer of black coal and coke in the Czech Republic. With the market environment and competition from Poland, China, and other suppliers and with increasing customer needs for accurate compliance with required quality, OKD is forced to pay greater attention to quality control. At present, quality control requires information support which significantly affects the results obtained and thus the economics of coal and coke production and sales. In the past decade, IT support for quality control has gradually developed from simple accounting-like applications into sophisticated information systems. These systems allow online control of coal quality parameters during production. They are linked to the control systems in laboratories and integrated into the global information system for the sales and dispatch of coal and coke in OKD. In this way, the information support allows the utilization of more advanced methods of planning, production optimization, and accurate fulfillment of the contract requirements on the supplied products. As a result, the efficiency and economics of coal and coke production has been significantly improved. The team of our institute cooperates with OKD and contributes both directly to the development of information support for quality control and indirectly by training professionals who are able to design and implement solutions in this area. The article presents an overview of the current state of information systems for quality control and presents the challenges to be solved in this area.