Template-Type: ReDIF-Article 1.0 Author-Name: Ľ. Kubík Author-Workplace-Name: Department of Physics, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: V. Kažimírová Author-Workplace-Name: Department of Production Engineering, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Mechanical properties of pellets in compression Abstract: The paper deals with the evaluation of mechanical properties of the cylinder pellet samples. The pellets were made from hay by the granulating machine MGL 200 (Kovonovak) provided by the Department of Production Engineering, Slovak University of Agriculture in Nitra. The pellets were submitted to compressive loading. The compressive loading curves of dependencies of force on strain and force on time were realised by the test stand Andilog Stentor 1000. Certain mechanical parameters were determined, namely the diameter of the sample, length of the sample, force at 10% of strain, force in the first maximum of the force - strain curve, strain in the first maximum of the force - strain curve, modulus of elasticity, force in the inflex point of the force - time and force - strain curves and strain and stress in the inflex point of the force - time and force - strain curves. Significant correlations of the mechanical parameters were observed between the inflex point and the first maximum point of the loading curves. There were find out, the compression force, stress and strain in the inflex point significantly correlate with the force, stress and strain in the first maximum. Keywords: deformation stress, inflex point, Young's modulus Journal: Research in Agricultural Engineering Pages: S1-S8 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/17/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/17/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0001.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:17-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: I. Karandušovská Author-Workplace-Name: Department of Structures, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: Š. Mihina Author-Workplace-Name: Department of Production Engineering, Faculty of Engineering, Slovak University of Agriculture in Nitra, Slovak Republic; National Agricultural and Food Centre, Nitra, Slovak Republic Author-Name: M. Bošanský Author-Workplace-Name: Department of Structures, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Impact of construction and technological solution of dairy cows housing on production of ammonia and greenhouse gases in winter Abstract: The aim of this experiment was to analyze the changes of ammonia production and greenhouse gases in frequent type of stables for dairy cows in winter. Two analyzed stables were situated side by side, one of which is after reconstruction of housing and ventilation technology and the second stable remained in original state. Variances of the mass concentration of gases differed significantly (P < 0.05), and the production of all gases monitored in winter was higher in the original stable. The average ammonia production was 2.45 ± 1.9 mg/m3 in the reconstructed stable, while in the original stable it was 5.1 ± 2.7 mg/m3. Average CO2 production was nearly twice higher in the unreconstructed building, namely 2,045.5 ± 862.3 mg/m3, while in the renovated facility it was 1,254.2 ± 416.2 mg/m3 (P < 0.05). The described type of reconstruction provides increased comfort for animals, which gives rise to a significant increase in production parameters, but also allows up to twice the reduction of hazardous pollutants such as CO2 and ammonia Keywords: pollutants, methane, dairy housing, microclimate Journal: Research in Agricultural Engineering Pages: S13-S20 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/21/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/21/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0002.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:21-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: J. Chrastina Author-Workplace-Name: Department of Production Engineering, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: L. Staroňová Author-Workplace-Name: Department of Production Engineering, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: I. Vitázek Author-Workplace-Name: Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: M. Pšenka Author-Workplace-Name: Department of Production Engineering, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Analysis of residual biomass of liquid biofuels using gravimetric method and combustion heat Abstract: The using possibilities of secondary raw materials produced during the liquid biofuels production such as bioethanol and biodiesel, and also those produced during solid fuel production was determined. The study presents combustion of distiller's dried grain with solubles (DDGS) and pressing refuse of rapeseed methyl ester (RME). The combustion was done in gravimetric oven, according to the standards, under the laboratory conditions. Combustion heat of samples was measured with calorimeter IKA C5000. The results show the average combustion heat of 20.91 MJ/kg for DDGS and 18.996 MJ/kg for RME. Results are chronologically presented in tables and figures. Keywords: DDGS residuals, RME residuals, gravimetric method, combustion heat, ash, distiller's dried grain with soester Journal: Research in Agricultural Engineering Pages: S21-S25 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/22/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/22/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0003.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:22-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Žitňák Author-Workplace-Name: Department of Structures, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: K. Kollárová Author-Workplace-Name: Department of Structures, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: M. Macák Author-Workplace-Name: Department of Structures, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: M. Prístavková Author-Workplace-Name: Department of Structures, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: M. Bošanský Author-Workplace-Name: Department of Structures, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Assessment of risks in the field of safety, quality and environment in post-harvest line Abstract: The objective of this work is the evaluation of threats in the field of safety, fire safety, quality and environment in the post-harvest treatment of grain, with an emphasis put on pre-cleaning and drying of grain. The paper describes the technology of pre-cleaning and drying of grain. Risks for individual machines were evaluated using a failure mode and effects analysis (FMEA), which is used to evaluate the threats in terms of fire risk, occupational safety, the effect of machine on the quality of final product, and effect on the environment. We have proposed measures and solutions to eliminate or minimise the consequences of threats. Risk rates are evaluated before and after measures adopted. It can be stated based on the results that risk was successfully reduced to an acceptable level after adopting measures. Keywords: FMEA, fire safety, analysis of threats Journal: Research in Agricultural Engineering Pages: S26-S36 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/23/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/23/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0004.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:23-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: R. Abrahám Author-Workplace-Name: Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: R. Majdan Author-Workplace-Name: Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: R. Drlička Author-Workplace-Name: Department of Quality and Engineering Technologies, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Possibilities of improving the wheel tractor drive force transmission to soil Abstract: The possibility of increasing maximal drawbar pull of tractor working on the soil was evaluated. The increase in drawbar pull occurred due to special wheels mounted on the drive axle. The special wheels were equipped with auto-extensible blades and designed at the Slovak University of Agriculture in Nitra. The main advantage of the special wheels is an automatic extension of steel blades to increase the drawbar pull during a wheel slip and automatic return to the base position to allow the transport of tractor by the route. The testing operation points at the decrease of wheel slip resulted in the increase of drawbar pull. The drawbar pull of tractor equipped with standard tyres and special wheels was compared in different soil moisture conditions. The higher increase in drawbar pull was measured during the tractor operation on the soil with higher moisture in comparison to the soil with lower moisture level. Keywords: tractor drawbar pull test, soil moisture, adapter, auto-extensible blades wheel, tipping spikes Journal: Research in Agricultural Engineering Pages: S37-S42 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/26/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/26/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0005.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:26-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Kotus Author-Name: E. Jankajová Author-Name: M. Petrík Title: Quality control of aluminium melt in production process Abstract: The quality of aluminium alloy in the production process on the chemical composition basis was evaluated. The quality of casting alloy depends on the chemical composition of melt and on the technological process of production process. The basic elements such as Si, Cu, Fe, Mg and Al in melting were evaluated. The obtained data were compared with the guide data referred to in the standard for aluminium alloy. Keywords: die casting, aluminium alloy, chemical composition, melting process Journal: Research in Agricultural Engineering Pages: S43-S47 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/28/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/28/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0006.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:28-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Olejár Author-Workplace-Name: Department of Electrical Engineering, Automation and Informatics, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: V. Cviklovič Author-Workplace-Name: Department of Electrical Engineering, Automation and Informatics, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: D. Hrubý Author-Workplace-Name: Department of Electrical Engineering, Automation and Informatics, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: O. Lukáč Author-Workplace-Name: Department of Electrical Engineering, Automation and Informatics, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Autonomous control of biaxial tracking photovoltaic system Abstract: Tracking photovoltaic systems maximize solar energy on the photovoltaic cells surface in order to maximize the energy gain at a given moment. Energy gain is dependent on the accuracy of photovoltaic cells direction, control method and tracking period. The control of tracking systems is based on theoretical calculations of sun position for a specific position in specific time. Designed control algorithm of the biaxial tracking photovoltaic system is able of autonomous navigation directed to the sun without knowing the position. It is based on the sun position sensor. The designed solution increases the solar gain by 33.8% in comparison with stable photovoltaic systems. It is usable in the research focused on the control method of step-controlled biaxial tracking photovoltaic devices. Keywords: tracker, photovoltaic cell, sun position sensor, efficiency, renewable energy Journal: Research in Agricultural Engineering Pages: S48-S52 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/29/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/29/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0007.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:29-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Kučera Author-Workplace-Name: Department of Machine Design, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: V. Malý Author-Workplace-Name: Department of Machine Design, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: M. Kučera Author-Workplace-Name: Department of Machine Design, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Analysis of the loading process effect on the tribological node geometry change of agricultural machine Abstract: The effect of loading on the properties of selected sliding pairs has been analysed. The experimental tests were performed using the testing machine Tribotestor M10. The steel 11 600 and all-bronze sleeve of CuSn12 material has been selected as the elements of friction pair. Two oils were selected for lubrication of friction node - the mineral gear oil Madit PP80 and ecological oil Plantohyd 46 S. Chosen friction pairs were tested in three loading regimes (two dynamic processes and one static process). 60 tribological tests have been performed. The weight loss, the change of surface roughness and the absolute change of cylindricity of the friction pair elements were the tracked and analysed parameters. Based on the experiments, various effects of loading regimes may be concluded. The obtained results confirmed that the power spectral density of generated signal is probably an important criterion for assessment in terms of simulated random dynamic load in the given experiment. From the technical perspective, the power spectral density is actually the amount of energy supplied to the process. Keywords: tribotestor, random process, sliding node Journal: Research in Agricultural Engineering Pages: S53-S59 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/31/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/31/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0008.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:31-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: I. Janoško Author-Workplace-Name: Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: M. Čery Author-Workplace-Name: Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Degradation of animal malodour Abstract: Animal waste represents a significant threat to the environment. Degradation of waste from dead animals is in general carried out in specialized facilities (rendering plants) under specific rules and guidelines. In plant proximity, undesirable malodour is usually produced during the combustion process. This odour can be effectively reduced so that it does not negatively affect the environment and society. Degradation of animal waste malodour can be processed in ozonisers, thermal combustion devices or in bio washers. The purpose of this paper is to determine the limits of exhausts that are produced during direct combustion of animal waste malodour. The level of ammonia in the combustion air is dependent on the quality of raw material processed at rendering plants where the measurements were carried out. In order to reduce the economic costs, the use of alternative fuels (animal fat, heavy fuel oil) is recommended. Keywords: rendering plant, malodour, thermal oxidation, emission limits Journal: Research in Agricultural Engineering Pages: S60-S66 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/35/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/35/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0009.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:35-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Balková Author-Workplace-Name: Department of Structures, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: D. Páleš Author-Workplace-Name: Department of Machine Design, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Influence of material solution of cover shells on stable daylight Abstract: The impact of material solution of cover shells on stable daylight. Light is supplied to the stable via a roof skylight, where wired glass is the infill of skylight structure, through open side walls, whereby the influx of light on one side is influenced by the shelter, and through the open gates, which are located in the front walls of the stable were assessed. Measurements of light intensity inside the stable were carried out in two height levels. Simultaneously, measurements were performed outside, on non-shadowed plane. Daylight factor was calculated from the measured values of internal and external comparative illuminance. Resulting values were processed into tables and graphs. The roof skylight has clearly the greatest influence on the lighting of the stable. Its disadvantage is that the stable overheats in these places in summer. Here, it would be appropriate to replace the fill of the skylight with translucent light elements. Keywords: stable for dairy cows, shelter, skylight, illuminance, daylight factor Journal: Research in Agricultural Engineering Pages: S67-S73 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/47/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/47/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0010.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:47-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: R. Gálik Author-Workplace-Name: Department of Production Engineering, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: Š. Boďo Author-Workplace-Name: Department of Production Engineering, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: L. Staroňová Author-Workplace-Name: Department of Production Engineering, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Monitoring the inner surface of teat cup liners made from different materials Abstract: The modern milking equipment consists of several rubber parts. Among these rubber parts, the most important is a teat cup liner, which provides direct contact force to teat tissue. Properties of teat cup liners directly affect the technical and technological process of milking, udder health condition and quality of obtained milk. The aim of the study is to specify the inner surface roughness of cup liners made from different materials. Roughness was measured using Surftest-301 Mitutoyo connected to a printer. Teat cup liners were monitored and evaluated at three different locations of the inner surface, every three months in primary production. The obtained results showed linear regression between the inner surface roughness of teat cup liners and exposure time. Significant differences of selected indicators of silicone liners were observed with P-value (0.029) < alpha (0.05). The model equation shows that if the value of cup liners exposure time increases by one month, inner surface roughness is likely to increase by approximately 0.039 μm. Keywords: teat cup liner, exposure, roughness Journal: Research in Agricultural Engineering Pages: S74-S78 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/50/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/50/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0011.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:50-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Müller Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: J. Žarnovský Author-Workplace-Name: Department of Quality and Engineering Technologies, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: R. Drlička Author-Workplace-Name: Department of Quality and Engineering Technologies, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Recycling of Polyamide from Scrap Tyres as Polymeric Composites Abstract: Rubber granulate, metal waste and textile waste (polyamide fibres) come into the mechanical process of waste tyres recycling. The pollution and degradation processes are problematic in using of secondary raw material. The matrix was in the form of three various adhesives in testing - two-component epoxy adhesives and a polyester adhesive. The filler was in the form of textile waste (polyamide fibres) from the process of tyres recycling containing approximately 10-12% of rubber granulate. The filler was added in app. 15% of weight ratio into the matrix. The aim of the research was to determine a possible utilisation of unsorted textile waste from the process of tyres recycling in the area of polymeric composite systems. Keywords: adhesives, composite mixture, deformation, impact strength, tensile strength, polymers, waste Journal: Research in Agricultural Engineering Pages: S79-S83 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/51/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/51/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0012.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:51-2015-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Mojžiš Author-Workplace-Name: Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: I. Vitázek Author-Workplace-Name: Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: F. Varga Author-Workplace-Name: Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: S. Lindák Author-Workplace-Name: Department of Transport and Handling, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Experimental determination of lethal doses of heat in thermal weed control Abstract: Thermal weed control performed by weeders working on physical principles is already commonly used on farms dealing with bioproducts. It helps to reduce strenuous human labour and to effectively control weeds and, to some extent, pests and diseases threatening the crops. It also prevents other weeds from spreading by destroying them in the early growth stage. In addition, development of weeds is inhibited when the soil is not being ploughed. Effective deployment of these machines in practice is currently addressed by experts in the field, as well as the possibility of rational use of heat energy while achieving the maximum effect on weeds. This method in particular helps to reduce costs of thermal treatment, which are the key factor limiting widespread deployment of weeders. The paper introduces long-term research based on laboratory and field experiments, which is intended to broaden the knowledge regarding this issue. Keywords: weed control, non-chemical cultivation Journal: Research in Agricultural Engineering Pages: S9-S12 Volume: 61 Issue: SpecialIssue Year: 2015 DOI: 10.17221/20/2015-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/20/2015-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201510-0013.txt Handle: RePEc:caa:jnlrae:v:61:y:2015:i:SpecialIssue:id:20-2015-RAE