Template-Type: ReDIF-Article 1.0 Author-Name: T. Polonec Author-Workplace-Name: Department of Transport and Handling, Technical Faculty, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: I. Janoško Author-Workplace-Name: Department of Transport and Handling, Technical Faculty, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Title: Improving performance parameters of combustion engine for racing purposes Abstract: Mechanical parts of stock engine have a performance reserve which could be utilized when the engine is used under the race conditions. Especially normal turbocharged engines have their performance parameters designed to drive in traffic, where a good flexibility, reliability, fuel consumption and a long service life is required. It is possible to utilize the whole power of the engine, when changing or modifying some of its external parts and achieve better performance parameters without modifying or changing internal engine components. Performed changes must be realized thoughtfully and on the admittable level, so the engine and other drive train components would not be damaged. In our study we design several changes of external parts of engine which have a significant impact on the improvement of engine performance parameters. Their contribution has been verified in practice by an engine dynamometer. Keywords: engine, performance parameters, turbocharger, roller dynamometer Journal: Research in Agricultural Engineering Pages: 83-91 Volume: 60 Issue: 3 Year: 2014 DOI: 10.17221/26/2012-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/26/2012-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201403-0001.txt Handle: RePEc:caa:jnlrae:v:60:y:2014:i:3:id:26-2012-RAE Template-Type: ReDIF-Article 1.0 Author-Name: V.A. Revaskar Author-Workplace-Name: Department of Processing & Food Engineering, Maharana Pratap University of Agriculture and Technology, Udaipur, India Author-Name: P.S. Pisalkar Author-Workplace-Name: Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola, India Author-Name: P.B. Pathare Author-Workplace-Name: Department of Process & Chemical Engineering, University College Cork, Ireland Author-Name: G.P. Sharma Author-Workplace-Name: Department of Processing & Food Engineering, Maharana Pratap University of Agriculture and Technology, Udaipur, India Title: Dehydration kinetics of onion slices in osmotic and air convective drying process Abstract: The effect of different pre-treatments (i.e. osmotic dehydration in 10, 15 and 20°Brix NaCl solution and drying air temperature of 50, 60 and 70°C) on drying behaviour of onion slices were investigated. The onion slices were dried in a laboratory model tray dryer. Drying of onion slices occurred in falling rate period. Five thin-layer drying models (Exponential, Page, Henderson and Pabis, Logarithmic and Power law) were fitted to the moisture ratio data. Among the drying models investigated, the Page model satisfactorily described the drying behaviour of onion slices. The effective moisture diffusivity of pre-treated samples was higher than that of non-treated samples Keywords: onion, drying, mathematical models, diffusivity, osmotic dehydration Journal: Research in Agricultural Engineering Pages: 92-99 Volume: 60 Issue: 3 Year: 2014 DOI: 10.17221/22/2012-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/22/2012-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201403-0002.txt Handle: RePEc:caa:jnlrae:v:60:y:2014:i:3:id:22-2012-RAE Template-Type: ReDIF-Article 1.0 Author-Name: Š. Nedomová Author-Workplace-Name: Department of Food Technology, Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Author-Name: J. Buchar Author-Workplace-Name: Department of Physics, Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Title: Goose eggshell geometry Abstract: The paper presents a new approach of the eggshell geometry determination using and analysing the egg digital image and edge detection techniques. The detected points on the eggshell contour were fitted by the Fourier series. The obtained equations describing an egg profile were used to calculate the egg volume, surface area, and radius of curvature with much higher degree of precision in comparison with previously published approaches. The paper shows and quantifies the limitations of the common and frequent procedures. Keywords: image analysis, goose's egg, eggshell profile, radius of curvature, egg volume, egg surface area Journal: Research in Agricultural Engineering Pages: 100-106 Volume: 60 Issue: 3 Year: 2014 DOI: 10.17221/80/2012-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/80/2012-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201403-0003.txt Handle: RePEc:caa:jnlrae:v:60:y:2014:i:3:id:80-2012-RAE Template-Type: ReDIF-Article 1.0 Author-Name: I. Ahmadi Author-Workplace-Name: Department of Agronomy, College of Agriculture, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran Title: Development and evaluation of full-vehicle vibration model of MF 285 tractor Abstract: The vibration transmitted to the tractor driver not only leads to the driver health problems, but also reduces the driver working efficiency. One of the methods utilized to reduce driver vibration is the seat suspension system. Development of the tractor vibration model is the first step toward the implementation of the tractor seat suspension. In this research development and evaluation of full-vehicle vibration model of MF 285 tractor was considered. At validation phase, the developed model simulated the predictable outputs correctly. The modified parameters of the model reduced the simulation error by 30% compared to the model with primary parameters. Furthermore, considering the operation status of tractor engine in the simulated tractor, the simulation error was reduced from 45% to 27%. Keywords: step function, simulation, transmitted vibrations, Matlab software Journal: Research in Agricultural Engineering Pages: 107-114 Volume: 60 Issue: 3 Year: 2014 DOI: 10.17221/5/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/5/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201403-0004.txt Handle: RePEc:caa:jnlrae:v:60:y:2014:i:3:id:5-2013-RAE Template-Type: ReDIF-Article 1.0 Author-Name: E. Zdravecká Author-Workplace-Name: Department of Technologies and Materials, Faculty of Mechanical Engineering, Technical University in Košice, Košice, Slovak Republic Author-Name: J. Tkáčová Author-Workplace-Name: Department of Technologies and Materials, Faculty of Mechanical Engineering, Technical University in Košice, Košice, Slovak Republic Author-Name: M. Ondáč Author-Workplace-Name: Department of Technologies and Materials, Faculty of Mechanical Engineering, Technical University in Košice, Košice, Slovak Republic Title: Effect of microstructure factors on abrasion resistance of high-strength steels Abstract: Current development of high strength abrasion resistant steels is mostly oriented on high hardness, martensitic concept following the hypothesis that the abrasion resistance holds a proportional tendency with hardness. The various experimental observations have suggested that the high hardness of martenzite does not guarantee a high abrasion resistance because the brittle nature of martensite can lead to decrease their abrasive wear. The aim of this work was to analyse the influence of microstructure on abrasion resistance of selected high-strength low-alloyed steels used in the industry. The abrasive wear resistance of selected steels was obtained using an ASTM-G65 three-body abrasive wear test, microstructure and wear resistance determination. It was observed that grain refinement is an effective way of enhancing the abrasion resistance. In this context, micro alloyed steels offer an attractive combination of price and performance. Keywords: abrasive wear, working tools in agriculture, ASTM G65, mechanism of wear Journal: Research in Agricultural Engineering Pages: 115-120 Volume: 60 Issue: 3 Year: 2014 DOI: 10.17221/20/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/20/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201403-0005.txt Handle: RePEc:caa:jnlrae:v:60:y:2014:i:3:id:20-2013-RAE Template-Type: ReDIF-Article 1.0 Author-Name: P. Junga Author-Workplace-Name: Department of Agriculture, Food and Environmental Engineering, Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Author-Name: P. Trávníček Author-Workplace-Name: Department of Agriculture, Food and Environmental Engineering, Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Title: Analyses of the thermal characteristics of construction details at the biogas station plant Abstract: This paper presents analyses of the thermal characteristics of construction details at the biogas station plant, in order to investigate the impact of the thermal bridges on the energy consumption. Thermal bridges in the building's envelope remain a weak spot in the constructions. Heat losses of biogas plant constructions are a negative phenomenon and cause wasting of energy. If we eliminate thermal bridges in constructions we can achieve a reduction of general heat losses and save a certain amount of heat energy for utilization. Correct structural design of construction details has impact on general environmental and economic characteristics of biogas plant. Keywords: buildings, thermal bridges, thermal losses, energy consumption Journal: Research in Agricultural Engineering Pages: 121-126 Volume: 60 Issue: 3 Year: 2014 DOI: 10.17221/29/2012-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/29/2012-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201403-0006.txt Handle: RePEc:caa:jnlrae:v:60:y:2014:i:3:id:29-2012-RAE