bluuebunny/crossref_metadata_2025 huggingface dataset:
APPLICATION OF TRIBOTECHNICAL DIAGNOSTIC METHODS IN CASE OF DETERMINATION OF COEFFICIENT OF OPERATIONAL RELIABILITY OF MACHINE TOOLS
Authors:   Technical University of Kosice, Faculty of Manufacturing, Technologies with a seat in Presov, Department of Design and Monitoring of Technical Systems, MASCENIK JOZEF
Published: December 2022

The submitted paper analyses the check of operational capacity and of economic efficiency of the selected machines in case of the use of different types of oil, determination of mode of friction and of machine wear and specification of interval of oil change. The object of the paper is a machine park in the industrial company comprising of five machine tools. Particularly, it is the case of two grinding machines, two lathes and one milling cutter. Having been removed from the greasing systems, the oils were used to gain information on technical condition of the respective machines.
ERGONOMIC RISK ASSESSMENT OF TAKING THE PRODUCT DIRECTLY FROM THE PRODUCTION LINE
Authors:   Technical University of Kosice, Faculty of Mechanical Engineering, Department of Safety and Production Quality, ONOFREJOVA DANIELA , PACAIOVA HANA ,   Technical University of Kosice, Faculty of Mechanical Engineering, Department of Safety and Production Quality, KOTIANOVA ZUZANA ,   Technical University of Kosice, Faculty of Mechanical Engineering, Department of Safety and Production Quality, GLATZ JURAJ ,   Technical University of Kosice, Faculty of Mechanical Engineering, Department of Safety and Production Quality, KULKA JOZEF ,   Technical University of Kosice, Faculty of Mechanical Engineering, Department of Safety and Production Quality
Published: December 2022

Creating healthy workplaces considering ergonomic risks is becoming a necessary part of preventive approach in design of workplaces. Preventive approach has positive impact including economical, health and safety measures. Corrective approach can be used when e.g. health issues must be improved. Performance analysis is important for employers in competitive domestic or global market. If the analysis is made on the basis of faulty or incomplete information, such analysis may not be reliable and consequently the decision made might yield an unexpected result. Thus, proper usage of performance indicators is vital to avoid mistakes and minimise such risk. Our study is focused on workplace in automotive industry, where worker removes product from the line and place the product in crates located next to the line. Worker prepares crates continuously after he fills them with product for full capacity. Quantitative analysis of ergonomic risk was performed with wireless multisensory measurement system Captiv, based on complaints from workers related to upper limbs and neck pain. Improvements in workplace design were suggested, also process changes were analysed by working posture analysis based on results measured with Captiv system.
TESTING HUMAN ERRORS IN VIRTUAL REALITY TRAINING
Authors:   Brno University of Technology, Dept. of Production Systems and Virtual Reality, KOTEK LUBOS , TUMA ZDENEK ,   Brno University of Technology, Dept. of Production Systems and Virtual Reality, SUBRT KAMIL ,   Brno University of Technology, Research Center of Automatic Manipulation, KROUPA JIRI ,   Brno University of Technology, Production Machines and Robotics Division, BLECHA PETR ,   Brno University of Technology, Dept. of Quality, Reliability and Safety, ROZEHNALOVA JANA ,   Brno University of Technology, Dept. of Quality, Reliability and Safety, BLECHA RADIM ,   Brno University of Technology, Research Center of Automatic Manipulation, HEINRICH PETR ,   Kovosvit MAS
Published: December 2022

The emergency training of industrial process plant operators is one of the most widely used tools to increase the reliability of human factors to handle an emergency situation. However, the preparation and operation of full-fledged simulators and trainers is very expensive and, therefore, virtual environment tools are used. A question that has not yet been answered is: Can virtual reality match the reliability of other methods of operation and is the same training in virtual reality effective? The experiment was carried out in the three-walled virtual CAVE, with virtual reality glasses, with a computer, a tablet, and a real control panel. Visual stimuli were displayed on the screen of the virtual monitor (green, yellow, and red); auditory stimuli were pure tones with frequencies of 250, 1000 and 4000 Hz. The conclusion should explicitly state if the hypothesis defined for the research has been confirmed and there are significant differences in terms of interface type. Training in virtual reality induces lower operator reliability, but in specific conditions (visual stimuli, virtual reality glasses) can match the reliability of other methods of operation and can be effective.
PROCEDURE OF APPLYING THE GENETIC ALGORITHM FOR THE CREATION OF A PRODUCTION LAYOUT
Authors:   University of Zilina, Faculty of Mechanical Engineering, Department of Industrial Engineering, KRAJCOVIC MARTIN , ANTONIUK IVAN ,   University of Zilina, Faculty of Mechanical Engineering, Department of Industrial Engineering, PAPANEK LADISLAV ,   University of Zilina, Faculty of Mechanical Engineering, Department of Industrial Engineering, FURMANN RADOVAN ,   University of Zilina, Faculty of Mechanical Engineering, Department of Industrial Engineering, BINASOVA VLADIMIRA ,   University of Zilina, Faculty of Mechanical Engineering, Department of Industrial Engineering, BASTIUCHENKO VSEVOLOD ,   University of Zilina, Faculty of Mechanical Engineering, Department of Industrial Engineering
Published: December 2022

Due to the rapid increase and development of new information technologies, it is now possible to collect real data from the production process, thereby creating an image of a real plant in a virtual environment. The concept of a digital twin in the design of production systems consists of creating a digital twin of the entire production plant, which consists of a digital, real and virtual enterprise, which is a fundamental difference between the design of production systems in the concept of a digital enterprise and in the concept using a digital twin. The paper deals with the methodology of data collection, layout creation and the company's digital twin. The practical benefits of the proposed solution are mainly from the point of view of reducing the necessary time when designing the production layout, especially in the phase of variant design. Closely related to this is the possibility of checking a larger set of solutions, taking into account various limiting conditions. As this proposed solution reduces the time required in the phase of variant design, costs necessary for the creation of a new or changing production layout are reduced.
COMPLETE DYNAMIC MODEL VALIDATION OF 3- DOF COMPLIANT MANIPULATOR WITH FLUIDIC MUSCLES
Authors:   Technical University of Kosice, Faculty of Manufacturing Technologies with the Seat in Presov, Department of Industrial Engineering and Informatics, CAKURDA TOMAS , TROJANOVA MONIKA ,   Technical University of Kosice, Faculty of Manufacturing Technologies with the Seat in Presov, Department of Industrial Engineering and Informatics, HOSOVSKY ALEXANDER ,   Technical University of Kosice, Faculty of Manufacturing Technologies with the Seat in Presov, Department of Industrial Engineering and Informatics
Published: December 2022

The article is devoted to the description of the validation of the dynamic model of an angular manipulator with three degrees of freedom of movement based on the chosen course of excitation of pneumatic artificial muscles from the manufacturer FESTO. The dynamic model consists of the dynamics of the manipulator arm and the dynamics of the pneumatic part of the experimental system. The motion equations were derived based on Lagrangian formalism and the dynamic of muscle contraction can be described using Newton's second law. The overall model of the system was implemented in the Matlab Simulink environment. The outputs of the validations were compared with the measured data from the real system. The observed parameter was the angle of rotation of the joint. Two statistical indicators were used to compare the simulation outputs (model) with the system outputs (measurements), namely NRMSE (Normal Root Mean Square Error) and MAE (Mean Absolute Error).
APPLICATION OF PROGRESSIVE TECHNOLOGIES BASED ON DIGITALIZATION IN MECHANICAL ENGINEERING
Authors:   University of Zilina, Faculty of Mechanical Engineering, Department of Automation and Production Systems, KLACKOVA IVANA , IVANOVA TATYANA ,   Institute of Mechanics of Udmurt Federal Research Center of the Ural Branch of the Russian Academy of Sciences, KURIC IVAN ,   University of Zilina, Faculty of Mechanical Engineering, Department of Automation and Production Systems, KORSHUNOV ALEKSANDR ,   Institute of Mechanics of Udmurt Federal Research Center of the Ural Branch of the Russian Academy of Sciences, KORETCKIY VLADIMIR ,   Kalashnikov Izhevsk State Technical University
Published: December 2022

Using digital technologies in its activities, an oil producing enterprise is able to gain a success only when a strategic approach is applied and, establishing a balance between actual and actual capability is equal to capability to beneficial transformations. The oil-extracting businesses digitalization of oil producing enterprises fundamentally alters key technologies throughout the entire life cycle from geological modelling, drilling and field development to commercial oil production. Peculiar to each stage of the life cycle, tools appear to evolve and transform themselves in accordance with the development of the enterprise. At the moment, advanced production technologies that are most in demand at oil producing enterprises are digital engineering, simulation modelling, smart manufacturing technologies, industrial Internet of things and artificial intelligence, virtual and augmented reality. Digital technologies enable production losses, mean time between failures, recovery time or downtime to be better foreseen and improve decision-making, early failure detection, calculate capital costs, operating costs and net present value for each particular well or for the deposit or oil field as a whole. The entire implementation of the project with digital technologies occurs according to the order: data collection, data research, modelling, analysis of results, testing the model’s performance on other wells, and replication.
THE INFLUENCE OF HYDROGEN CONCENTRATION IN NATURAL GAS ON HEAT FLOWS IN A THERMAL AGGREGATE
Authors:   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, RIMAR MIROSLAV , KIZEK JAN ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, VARGA AUGUSTIN ,   Technical University of Kosice, Faculty of Materials, Metallurgy and Recycling, Institute of Metallurgy, FEDAK MARCEL ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, JABLONSKY GUSTAV ,   Technical University of Kosice, Faculty of Materials, Metallurgy and Recycling, Institute of Metallurgy
Published: December 2022

Natural gas is currently a hotly debated topic both from an environmental point of view due to the production of CO2 and from an economic point of view. The article is focused on the analysis of selected energy factors when burning natural gas with a gradual increase in the hydrogen content in the fuel mixture. In the article, the authors focused on modelling combustion and the influence of hydrogen concentration on heat flows from flue gas in a thermal aggregate. The aim of the authors is to point out changes combustion in the thermal aggregate using document analysis and calculations. By gradually increasing hydrogen in natural gas, it is possible to prove the effect on heat flows during the exchange of heat from the flue gas to the heated material. According to the results, it can be concluded that increasing the content of methane in natural gas changes the nature of the combustion of the mixture. The combustion temperature increases, heat flow density, on the other hand, the volume of flue gas converted to 1 m3 of fuel decreases. An important factor that positively decreases in this is the CO2 emission factor.
PRINT SPEED AND ITS IMPORTANCE FOR METAL ADDITIVE MANUFACTURING
Authors:   University of West Bohemia, Faculty of Mechanical Engineering, Regional Technological Institute, NOZAR MARTIN , ROSENTHAL JAKUB ,   Faculty of Mechanical and Environmental Engineering, OTH
Published: December 2022

The article deals with issues which occur when using different types of basic print speeds in metal additive manufacturing. It describes their importance, mutual relationships and their influence on the quality of pieces manufactured using this technology. The ability to manage the speed of the additive manufacturing process allows us not only to effectively improve print quality but also, for example, to reduce the volume of necessary support structures. It thus speeds up the whole printing process, minimizes material waste, and reduces the need for any finishing operations which may be necessary for achieving the required final properties of the printed parts. In this context, the connection between the quality and the speed of additive manufacturing is demonstrated in a simple experiment using Powder Bed Fusion technology (PBF) in which the effect of the print speed on various low-angled flat surfaces is observed.
A VIEW ON HUMAN CAPITAL IN INDUSTRY 4.0
Authors:   Slovak University of Technology in Bratislava, Faculty of Science and Technology in Trnava, MARKOVA PETRA , HOMOKYOVA MARIA ,   Slovak University of Technology in Bratislava, Faculty of Science and Technology in Trnava, PRAJOVA VANESSA ,   Slovak University of Technology in Bratislava, Faculty of Science and Technology in Trnava, HORVATHOVA MARTINA ,   Slovak University of Technology in Bratislava, Faculty of Science and Technology in Trnava
Published: December 2022

The article's subject is the definition of areas where space is created for targeted workforce management and its successful implementation within the Industry 4.0 concept. In most cases, if we talk about the performance of Industry 4.0 elements, the investments of enterprises are primarily directed to the area of production, information and communication technologies, research and development, not to the formation of specific competencies of Work 4.0 and support for the implementation of human capital in practice. It is generally assumed that introducing Industry 4.0 will mean a lower need for labour for the enterprise, which will be replaced by a higher degree of automation and robotization. It is essential to recognize that human participation will still be required in work systems that are more automated and digitized, but that humans need to be sufficiently prepared for the changed way of doing work. The digitalization of the economy is not only creating new jobs and occupations but is also creating the need for new skills for employment. Employees will need to be willing and able to continue to learn and acquire new skills. It is essential to work with the workforce in the enterprise and gradually equip them with the missing skills and abilities. Several analytical methods were used to obtain the analytical background to identify areas of investment for companies in Industry 4.0 and to identify threats and risks associated with implementing Industry 4.0. An important component was the perspective of the affected employees and their perception of disadvantages within Industry 4.0. The analysis findings are used to understand better the workforce status in the enterprise and the gaps where space is created for workforce development in the changing needs of industrial enterprises in the Industry 4.0 environment.
GEOMETRIC PRECISION OF THE CYLINDERS SURFACES MACHINED WITH WEDM TECHNOLOGY
Authors:   Technical University of Kosice,Faculty of Manufacturing Technologies with a seat in Presov, Department of Automotive and Manufacturing Technologies, STRAKA LUBOSLAV ,   Department of Technical Systems Design and Monitoring, KRENICKY TIBOR ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Automotive and Manufacturing Technologies; Department of Technical Systems Design and Monitoring
Published: December 2022

One of the progressive production technologies through which it is possible to machine complicated shapes in materials characterized by high hardness is electrical discharge machining with a wire electrode. However, as with other progressive technologies, in the case of electrical discharge machining technology, demanding customer requirements for the geometric accuracy of the machined surface are not always met. These errors occur for various reasons. These are, for example, the vibrations of the wire tool electrode, its destruction during the machining process, the setting of technological and process parameters, but also errors in the design of the machine and the software control of the tool path. These and other errors have a primary role in the emergence of geometric inaccuracy of the machined surface after electrical discharge machining with a wire tool electrode. A special problem in the case of electrical discharge technology is the machining of internal and external cylindrical surfaces. As a result of the mentioned causes, deviations occur during their machining, which subsequently cause problems for the manufactured products during their assembly as well as the operation itself. Therefore, the objective of the experimental research was to identify the extent of these geometric deviations on the inner and outer cylindrical surfaces during electrical discharge machining with a wire tool electrode.
RHEOLOGICAL PROPERTIES OF POLYMER-POLYMER MIXTURES ON CORN STARCH BASE
Authors:   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Institute of Manufacturing and Process Engineering, RIMAR MIROSLAV , TRETYAKOFF ARTEM ,   Ukrainian State University of Chemical Technology, SUKHYY KOSTYANTYN ,   Ukrainian State University of Chemical Technology, YEROMIN ОLEKSANDR ,   Ukrainian State University of Science and Technologies, Institute of Industrial and Business Technologies, KULIKOV ANDRII ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Institute of Manufacturing and Process Engineering, FEDAK MARCEL ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Institute of Manufacturing and Process Engineering, BELYANOVSKAYA ELENA ,   Ukrainian State University of Chemical Technology, SHUNKIN IHNAT ,   Ukrainian State University of Chemical Technology, GUPALO OLENA ,   Ukrainian State University of Science and Technologies, Institute of Industrial and Business Technologies, KRENICKY TIBOR ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Institute of Manufacturing and Process Engineering
Published: December 2022

The prospects for the use of polymer-polymer mixtures based on corn starch as alternative thermoplastic materials to polyolefins are considered. Rheological curves have been obtained, which confirm the possibility of processing such mixtures on standard equipment into products. It is shown that the starch content in polymer-polymer mixtures can reach 90 mass percent. Compared to existing biodegradable polymers, plasticized starch-based material is in no way inferior to them in terms of processability. Studies of the mechanical properties of polymerpolymer mixtures based on corn starch have been carried out. The data obtained indicate the possibility of using the developed composites as packaging materials, as well as alternative materials to known bioplastics and synthetic polymers.
DESIGN OF METHOD FOR NONLINEAR SHEAR MODULUS MEASURING IN GEL-LIKE MEDIUM BY APPLYING AN ADDITIONAL STATIC STRESS TO AN ACOUSTIC RESONATOR
Authors:   University of Zilina, Faculty of Mechanical Engineering, Department of Applied Mechanics, SAGA MILAN , KRIT TIMOFEY B. ,   M.V. Lomonosov Moscow State University, Faculty of Physics, Department of Acoustics, SAGOVA ZUZANA ,   University of Zilina, Faculty of Mechanical Engineering, Department of Automation and Production Systems, ASFANDIYAROV SHAMIL A. ,   M.V. Lomonosov Moscow State University, Faculty of Physics, Department of Acoustics, ANDREEV VALERY G. ,   M.V. Lomonosov Moscow State University, Faculty of Physics, Department of Acoustics, YAKIMOVICH BORIS A. ,   Sevastopol State University, Institute of Nuclear Energy and Industry, KUVSHINOV VLADIMIR V. ,   Sevastopol State University, Institute of Nuclear Energy and Industry
Published: December 2022

Measurements of the nonlinear parameter of a gel-like medium were carried out in an acoustical resonator fixed without slipping between two solid-state boundaries. A sample of thickness L is fixed on an oscillating plate (x = 0). The other plate of finite mass on the free surface of the sample (x = L) moves together with this surface. By changing the mass of the plate (x = L), it is possible to achieve additional static deformation of the resonator up to 65%. The dynamic method assumes measuring resonance curves at various static deformations. Nonlinear properties appear at deformations of more than 20%. The nonlinear parameter and shear modulus measured dynamically were compared to static measurements where the dependence becomes nonlinear at strains greater than 30%. The static values of the shear modulus and the nonlinear parameter correspond to the values obtained in the dynamic method within an error.
INCREASE OF INDUSTRIAL ROBOT ACCURACY BASED ON KINEMATIC ERRORS COMPENSATION
Authors:   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of production machines and equipment, CHLADEK STEPAN , SVEDA JIRI ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of production machines and equipment, SIKA ZBYNEK ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics, BENES PETR ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics
Published: December 2022

Industrial robots are used in many technical applications from simple pick-and-place tasks to complex machining, welding and assembly applications. The repeatability of the robots is usually high. However, the accuracy is much lower, and it decreases with the robot size selected. Robot calibration represents a possible way to increase accuracy, and two main approaches have been distinguished. Kinematic calibration deals with geometric errors only, and the robot is considered as a rigid body. By contrast, non-kinematic calibration takes into account further sources of errors. This paper deals with kinematic calibration, where an artifact is attached to a robot flange and its position is measured using a laser tracker. The novelty of the method is based on the consecutive rotation of only a single joint, where the artifact trajectory is circular. Real robot geometry is calculated based on identified circles. Numerical simulations seem promising, as well as verification with Stäubli TX2-90, where the accuracy was increased by more than 43%.
AN UPDATE OF THERMAL ERROR COMPENSATION MODEL VIA ON-MACHINE MEASUREMENT
Authors:   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment, RCMT, MARES MARTIN , HOREJS OTAKAR ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment, RCMT, STRAKA MICHAL ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment, RCMT, SVEDA JIRI ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment, RCMT, KOZLOK TOMAS ,   TOS VARNSDORF a. s.
Published: December 2022

Software compensation is state-of-the-art technology used to reduce CNC machine tool thermal errors, and it belongs to a key intelligent functions of modern machine tools. However, a pretrained and nonadaptive model may not be accurate and robust enough for long-term application. This research presents a transfer function based thermal error compensation model updated via on-machine measurement. A mathematical model is implemented into the machine management software of a large horizontal machining centre to compensate for thermal errors in real time using C#/C++ programming language. The results show that after the thermal error compensation model is updated via on-machine measurement, the prediction accuracy, measured as peak-to-peak values, and the normalized root mean squared error are significantly improved. The prediction accuracy of the compensation model updated via on-machine measurement strongly depends on the sampling interval of the on machine measurements.
ISSUES OF CYBERSECURITY OF THE PRODUCTION SYSTEM
Authors:   Brno University of Technology, Faculty of Mechanical Engineering, Institute of Production Machines, Systems and Robotics, MARADOVA KARLA , BLECHA PETR ,   Brno University of Technology, Faculty of Mechanical Engineering, Institute of Production Machines, Systems and Robotics, BLECHA RADIM ,   Brno University of Technology, Faculty of Mechanical Engineering, Institute of Production Machines, Systems and Robotics, ROZEHNALOVA JANA ,   Brno University of Technology, Faculty of Mechanical Engineering, Institute of Production Machines, Systems and Robotics, FRKAL VOJTECH ,   TOSHULIN As
Published: December 2022

Cybersecurity of production systems is a very topical issue in response to the dangers associated with the very high number of cyber-attacks in Europe. The current digital transformation of the industry associated with the digitalisation of manufacturing brings both the positives associated with increased flexibility and productivity of production, and the negatives associated with the risk of data loss, data alteration or blocking of control systems. Cybersecurity issues are also reflected in the revision of EU harmonisation legislation governing the requirements for placing products on the market or in service. It appears that the issue of cyber security needs to be addressed comprehensively across the entire infrastructure of a manufacturing plant. The present paper focuses on the relationship between machinery security and OT/IT security and presents the results of a study aimed at identifying potential sources of threats in an integrated manufacturing system.
THERMO-MECHANICAL ANALYSIS OF A MACHINE TOOL WITH HYDROSTATIC BEARINGS
Authors:   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT), STACH EDUARD , SMOLIK JAN ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT), SULITKA MATEJ ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT), LAZAK TOMAS ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT), DIVIS IVAN ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT), FALTA JIRI ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT)
Published: December 2022

Thermal behaviour is a key factor affecting the operatingstatus of high performance hydrostatic (HS) bearings of rotational axes of machine tools (MT). This paper introduces a novel model developed for transient thermo mechanical analysis of hydrostatic guideways with a surrounding MT structure. In contrast to common approaches to HS bearing design, which only consider the static load carrying capacity, the new model enables detailed prediction of the bearing thermal stability under various operating conditions. An analytical description of the HS bearing heat generation coupled with a MT finite element (FE) model enables calculation of heat transfer, conduction and especially thermal deformations of the entire MT structure affecting the working accuracy of the machine tool.
COMPENSATIONOF WORKTABLEMOTIONERROR BYANACTIVELY CONTROLLEDHYDROSTATIC GUIDEWAY
Authors:   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT), LAZAK TOMAS , STACH EDUARD ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT), SMOLIK JAN ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT), DIVIS IVAN ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT), FORNUSEK TOMAS ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment (RCMT)
Published: December 2022

The accuracy of machine tools is limited by many factors,such as geometric and thermal errors. Current error reduction approaches include e.g. volumetric compensation. However, if a machine tool has only linear axes, angular errors cannot be compensated since there is no controllable axis that could change the tool or workpiece inclination. Therefore, an actively controlled hydrostatic guideway was developed to compensate for angular and other geometric errors. This paper aims to experimentally verify the hybrid use of constant resistance and the pilot stage of an industrial proportional pressure relief valve for regulation of oil flow through hydrostatic pockets and control of these pockets as well as active compensation of machine tool geometric errors. The error reduction of the tested linear axis is presented.
INFLUENCE OF COMPOSITE SPINDLE RAM ON MACHINE TOOL DYNAMIC STIFFNESS
Authors:   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment, Research Center of Manufacturing Technology, KULISEK VIKTOR , KOLAR PETR ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment, Research Center of Manufacturing Technology, SMOLIK JAN ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment, Research Center of Manufacturing Technology, RUZICKA MILAN ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics, JANOTA MIROSLAV ,   Czech Technical University in Prague, Faculty of Mechanical Engineering, Department of Production Machines and Equipment, Research Center of Manufacturing Technology, MACHALKA MARTIN ,   TAJMAC-ZPS, a. s.
Published: December 2022

Demands for improving machine tool productivity and accuracy can be addressed using alternative material structures with the potential to reduce the mass of moving bodies and decrease machine tool dynamic compliance. A useful option is to apply composite materials because they offer high damping and low density in comparison with steel or cast iron. The key question is how the stiffness and damping of a single composite or hybrid metal + composite component influences the behaviour of the machine tool. In this paper, simulation models for the prediction of machine tool dynamic compliance were prepared for a detailed analysis of a use case study using a hybrid and ductile iron spindle ram for a portal milling centre. A simplified model for the damping matrix formulation was assembled and the influence of the spindle ram damping on the dynamic compliance was tested along with stiffness and mass change, leading to conclusions about the effect of a single component redesign. The minor influence of the material damping of the hybrid structure is noted, and factors influencing the final dynamic compliance are discussed in detail.
SELECTION CRITERIA OF WORKING PAIRS ADSORBENT - ADSORBATE FOR THERMAL ENERGY TRANSFORMERS
Authors:   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, RIMAR MIROSLAV , SUKHYY KOSTYANTYN ,   Ukrainian State University of Chemical Technology, BELYANOVSKAYA ELENA ,   Ukrainian State University of Chemical Technology, YEROMIN ОLEKSANDR ,   Institute Of Industrial and Business Technologies, Ukrainian State University of Science and Technologies, PROKOPENKO ELENA ,   Institute Of Industrial and Business Technologies, Ukrainian State University of Science and Technologies, KULIKOV ANDRII ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, FEDAK MARCEL ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, FROLOVA LILIA ,   Ukrainian State University of Chemical Technology, PUSTOVOY GRIGORIY ,   Ukrainian State University of Chemical Technology, KULIKOVA OLHA ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, SAVKO VITALII ,   Ukrainian State University of Chemical Technology
Published: December 2022

In the manuscript the main factors that affect the thermal mass of open and closed types of heat storage devices are shown. Also, the main requirements for adsorption modules are given. The calculation procedure has been refined, which includes the determination of heat load, heat of adsorption, adsorbent mass, as well as integral, structural, and specific thermal mass. The specific thermal masses of adsorption heat-accumulating modules of open and closed types were evaluated. The main factors affecting their value are analysed. It is shown that the specific thermal mass of the adsorption heat storage module increases significantly due to the adsorption of water during the discharge of the device. It is shown that it reaches its maximum values at the end of the discharge stage, when the maximum values of adsorption in the cycle are reached. The influence of the design of the heat storage module on the value of the specific thermal mass has been confirmed. It is shown that the maximum values of these changes correspond to the composites containing 80% salt and 20% silica gel, due to the maximum values of the limiting adsorption and the heat of adsorption, which contributes to the lower values of the adsorbent mass, which is required to cover the thermal load. Specific thermal masses of adsorption modules based on "silica gel - sodium sulphate" and "silica gel - sodium acetate" composites are compared. The composition of the composite is 80% sodium sulphate and 20% silica gel, which corresponds to the minimum dimensions of the adsorption module, and therefore the maximum value of the specific thermal mass.
STUDY OF SELECTED BURNER PARAMETERS ON THE GAS-AIR MIXTURE COMBUSTION
Authors:   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, RIMAR MIROSLAV , KIZEK JAN ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, KULIKOV ANDRII ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique, FEDAK MARCEL ,   Technical University of Kosice, Faculty of Manufacturing Technologies with a seat in Presov, Department of Process Technique
Published: December 2022

The study of the combustion of a gas-air mixture using burners opens possibilities for further research, in which it is possible to modify the parameters of existing burners (geometry, method combustion air distribution, ...). Flame length can be influenced by changing some of the burner parameters to achieve the best possible conditions in the combustion chamber. The topic of the article is to study the effect of changing burner parameters on the length and nature of the flame in the combustion chamber. For this, an existing burner simulation model was modified. The properties of the proposed changes were investigated using the ANSYS simulation software. Simulation confirmed the suitability of the proposed system for reducing the flame length and intensifying the mixing of gaseous media. Also, the results show that the effect of changing the angle of combustion air supply along the longitudinal axis of the burner significantly affects the mixing of the fuel and, consequently, the nature of the flame with the combustion products.
CALIBRATION OF THE ROBOTIC ARM WITH CORRECTIONS USING LOCAL LINEAR NEURO-FUZZY MODELS
Authors:   Czech technical university in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics, BENES PETR , HLADIK JAN ,   Czech technical university in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics, PELIKAN JAN ,   Czech technical university in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics, NEUSSER ZDENEK ,   Czech technical university in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics, NECAS MARTIN ,   Czech technical university in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics, SVEDA JIRI ,   Czech technical university in Prague, Faculty of Mechanical Engineering, Department of production machines and equipment (RCMT), VALASEK MICHAEL ,   Czech technical university in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics, SIKA ZBYNEK ,   Czech technical university in Prague, Faculty of Mechanical Engineering, Department of Mechanics, Biomechanics and Mechatronics
Published: December 2022

The paper deals with the enhancement of the robotic arm calibration using corrections based on local linear neuro-fuzzy models. After the standard calibration of the geometric parameters in the robot's kinematic model, there are still residual errors between the measured positions and the positions predicted by the model. The source of these errors are various non-geometric parameters and nonlinear phenomena that traditional kinematic calibration models do not include. The neuro-fuzzy model based on a locally linear model tree can approximate the residual error as a function of the robot's joint angles. Adding this approximation to the output of the calibrated robot model significantly increases the accuracy of the endeffector position. The results of the described method were verified and compared with other approaches on a simulation model of a flexible planar two-link mechanism. Experimental verification was performed on an industrial robot Stäubli TX200 with data measured by Leica laser tracking device.
Propuesta TIC para clases invertidas en asignaturas de Diseño Mecánico
Authors: Jaimes-Rolon Ricardo Alonso
Published: December 2022

El contexto de esta propuesta se da en los procesos de enseñanza aprendizaje del diseño mecánico, especialmente en materias como Diseño Básico (5to Semestre), Diseño Grafico (3er Semestre) y Estática (3er Semestre) del programa de Ingeniería Mecánica de la UIS. Esta propuesta se ha estado trabajando desde hace 4 años aproximadamente.
Numerical Simulation of Influencing Factors to the Thermal Insulation Performance of Cold Chain Shipping Containers and Analysis of Internal Flow Field
Authors: He Shouhui , Wang Yan , Liu Hongda
Published: December 2022

Cold chain transportation can prolong the shelf lives of products and reduce losses, so based on the practical applications, it is necessary to numerically simulate the flow field and thermal insulation performance of cold chain shipping containers. Existing studies have achieved optimization by changing the thermal performance and thermal insulation mechanisms of the thermal insulation materials of the containers, but little research has been done on the numerical simulation of the factors affecting the thermal insulation performance of cold chain shipping containers. Therefore, this paper conducts the numerical simulation of the influencing factors to the thermal insulation performance of cold chain shipping container and studies the internal flow field. The structure and air supply diagrams of a cold chain shipping container were given, the thermal insulation performance of the thermal insulation sandwich panels in different surface layers and core layers of the cold chain shipping container was calculated and analyzed, and thermal inertia and heat transfer attenuation performance of the sandwich panels during the unsteady heat transfer process of the container were analyzed. The basic governing equations and assumptions were established for the internal flow field of the cold chain shipping container, and the distribution of the internal flow field was explored. With the impact of the viscosity of air molecules in the cold chain shipping container further ignored, the flow was regarded to be turbulent, and the internal flow field was simulated based on the turbulence-dissipation model. The experimental results were used to analyze the thermal insulation performance of cold chain shipping containers, and analysis results of the flow field where the cold chain shipping containers were stacked in different ways were given.
Manipulative Effect of Environmental Conditions on the Growth and Yield of Cucumber Nourished with Poultry Manure in Sandy Loam Soil
Authors: Ali Christian Chinedu , Asogwa Vincent Chidindu , Izuakor Chiamaka Francisca
Published: December 2022

There is high demand for cucumber because of its nutritional and medicinal implications. Despite the several benefits of the crop, there is little information on the agronomic performance of the crop in open and shaded conditions using different rates of poultry manure in south east Nigeria. The experiment was carried out to determine the effect of different rates of poultry manure on the growth and yield of cucumber in open and shaded conditions. This research was conducted in the research farm of the Agricultural Education Department, University of Nigeria, Nsukka. The experiment was laid out using RCBD (Randomized Complete Block Design) and replicated three times for both the open and shaded conditions. The poultry manure treatments applied were 0, 2 and 4ton/ha and data for the growth parameters were recorded on the 4th, 6th and 8th weeks after planting (WAP) while data on yield parameters were taken at harvest. The results indicated that cucumber planted under open system had the highest number of leaves, branches, stem girth, number of flowers, number of fruits and weight of fruits per plant when treated with 2ton/ha of poultry manure in comparison with 0ton/ha and 4ton/ha treatments under shaded system. The researchers therefore concluded that farmers in the study area can grow cucumbers in an open field with 2ton/ha poultry manure for optimal growth and yield of the crop.
Toxoplasma gondii Infection in Immunocompromised Patients in Iran (2013-2022): A Systematic Review and Meta-Analysis
Authors: Teimouri Aref , Goudarzi Fatemeh , Goudarzi Kimia , Alimi Rasoul , Sahebi Keivan , Foroozand Hassan , Hossein Keshavarz
Published: December 2022

Background: Toxoplasma gondii infection (toxoplasmosis) has the potential to cause a serious disease in immunocompromised patients and can be fatal in this population. We conducted a systematic review and meta-analysis to assess comprehensively the pooled seroprevalence of toxoplasmosis among immunocompromised patients including HIV/AIDS patients, cancer patients, and transplant recipients in Iran.
Methods: PubMed, Web of Science, Scopus, Embase, and Google Scholar databases (international) and Scientific Information Database (SID), Magiran, IranMedex, and IranDoc databases (national) were systematically searched for all reports that possibly contained data for T. gondii prevalence in different immunocompromised populations in Iran between 2013 and 2022.
Results: Overall, IgG seroprevalence rate of toxoplasmosis in Iranian immunocompromised patients was 45.1% (95% confidence interval (CI), 37.4–52.9). IgG seroprevalence rate of toxoplasmosis in 12 studies that included 2279 cancer patients, 19 studies that included 2565 HIV/AIDS patients and in 3 studies that included 200 transplant recipients was 43.6% (95% CI, 30.2–57.0), 45.9% (95% CI, 34.8–57.1) and 45.8% (95% CI, 32.5–59.0), respectively. Moreover, IgM seroprevalence rate in the 26 studies was 2.6% (95% CI, 1.4–3.7).
Conclusion: Our findings represent a high seroprevalence rate of Toxoplasma IgG among immunocompromised patients. Health improvement and education toward prevention of toxoplasmosis is of great importance for these susceptible populations.
Plant Bioactive Ingredients in Delivery Systems and Nanocarriers for the Treatment of Leishmaniasis: An Evidence-Based Review
Authors: Alanazi Abdullah D , Said Mourad Ben
Published: December 2022

Background: This study was designed considering the challenges of leishmaniasis treatment and the benefits of carriers of drug delivery systems to review plant bioactive ingredients in delivery systems and nanocarriers for the treatment of leishmaniasis.
Methods: The methodology of this review investigation followed the 06-PRISMA recommendations. The searches were carried out up to January 30, 2022, in the central English databases SCOPUS, WEB OF SCIENCE, EMBASE, PUBMED, and GOOGLE SCHOLAR using the search terms “ç”, “leishmaniasis”, “herbal medicines”, “drug delivery”, “nanocarriers”, “herbal compounds”, and “secondary metabolites”.
Results: Out of 5731 articles, 19 publications, including 12 in vivo (63.15%), 3 in vitro (15.8%), and 4 in vitro/ in vivo (21.1%) up to 2022, fulfilled the criteria presence for argument in the current systematic study. Plant bioactive ingredients were curcumin, betulinic acid, artemisinin, 4-nitrobenzaldehyde thiosemicarbazone, andrographolide, pentalinonsterol, ursolic acid, amarogentin, carvacrol, 14-deoxy-11-oxo-andrographolide, quercetin, beta-lapachone, cedrol, 2ˊ,6ˊ-dihydroxy-4ˊ-methoxychalcone, and oleanolic acid.
Conclusion: The high potential of plant bioactive ingredients in delivery systems due to the load on the nanocarrier for the treatment of leishmaniasis through some main mechanisms of action, e.g. changes in the fluidity and the structure of the cell wall, creation of reactive oxygen species (ROS) and mitochondrial dysfunction, inhibition of DNA topoisomerase I enzyme, minimal cytotoxicity, stimulation of cell cycle disruption, stimulation of apoptosis, enhancement of the immune system. However, further investigations, especially in the clinical setting, are required to confirm these findings.