Template-Type: ReDIF-Article 1.0 Author-Name: editors Title: Index of volume 59 Journal: Research in Agricultural Engineering Pages: I-II Volume: 59 Issue: 4 Year: 2013 DOI: 10.17221/7145-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/7145-RAE.html File-Format: text/html Handle: RePEc:caa:jnlrae:v:59:y:2013:i:4:id:7145-RAE Template-Type: ReDIF-Article 1.0 Author-Name: P. Trávníček Author-Workplace-Name: Department of Agricultural, Food and Environmental Engineering, Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Author-Name: M. Valach Author-Workplace-Name: Department of Physics, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: Z. Hlaváčová Author-Workplace-Name: Department of Physics, Faculty of Engineering, Slovak University of Agriculture in Nitra, Nitra, Slovak Republic Author-Name: J. Mareček Author-Workplace-Name: Department of Agricultural, Food and Environmental Engineering, Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Author-Name: T. Vítěz Author-Workplace-Name: Department of Agricultural, Food and Environmental Engineering, Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Author-Name: P. Junga Author-Workplace-Name: Department of Agricultural, Food and Environmental Engineering, Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Title: Selected physical properties of liquid biofuels Abstract: The goal of this study was the determination of basic physical properties such as density, calorific value and rheological properties of liquid biofuels. Biofuels on the base of bioethanol and rapeseed methyl ester were chosen. Following control samples were selected: diesel oil without admixture of methyl esters and commercially available diesel oils with small amount of methyl ester admixture (6.2 and 6.5%). Dynamic viscosities of individual samples were measured in the range from -10°C to 50°C. Then dependence of shear rate on shear stress was measured at temperatures -10, 0, 20 and 40°C. The most of samples showed the Newtonian behaviour. However, samples with high content of methyl esters or pure methyl esters showed thixotropy behaviour at the low temperature. Keywords: rheology, thixotropy, density, methyl ester Journal: Research in Agricultural Engineering Pages: 121-127 Volume: 59 Issue: 4 Year: 2013 DOI: 10.17221/14/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/14/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201304-0002.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:4:id:14-2013-RAE Template-Type: ReDIF-Article 1.0 Author-Name: R. Chotěborský Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Czech Republic Author-Name: P. Hrabě Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Czech Republic Title: Effect of destabilization treatment on microstructure, hardness and abrasive wear of high chromium hardfacing Abstract: Hardfacing metals are widely used in arc welding and plasma transfer arc technologies and industries. However, application of hardfacing in agriculture is limited due to low toughness after weld depositing. This study was focused on destabilization of high chromium hardfacing metal. The hardfacing was destabilized at 900 and 1,000°C in the different treatment time intervals. Destabilization treatment showed precipitation of secondary carbides leading to partial transformation of austenite to martensite phase in the matrix. The results show that increasing destabilization temperature increased volume of carbide phase in austenitic matrix which affects abrasive wear resistance. Keywords: weld deposit, heat treatment, carbides, precipitation, microhardness Journal: Research in Agricultural Engineering Pages: 128-135 Volume: 59 Issue: 4 Year: 2013 DOI: 10.17221/6/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/6/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201304-0003.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:4:id:6-2013-RAE Template-Type: ReDIF-Article 1.0 Author-Name: I. Ahmadi Author-Workplace-Name: Department of Agronomy, Khorasgan (Isfahan) Branch, Islamic Azad University, Isfahan, Iran Author-Name: H. Ghaur Author-Workplace-Name: Department of Agronomy, Khorasgan (Isfahan) Branch, Islamic Azad University, Isfahan, Iran Title: Silage-corn harvesting machinery traffic effects on soil bulk density and water permeability Abstract: Soil compaction caused by machinery traffic affects the growth of agricultural crops and also has environmental effects like soil damage and erosion. Field experiments were conducted to study the effects of repeated silage-corn harvesting machinery traffic on dry soil bulk density and porosity variations at three different sampling depths, moreover average water permeability coefficient of the examined silty clay loam soil was measured using the falling head method of water permeability test. The examined treatments which were applied while harvesting silage-corn with the combination of tractor, chopper and truck were the number of traffic passes and depths of soil sampling. Significant differences between soil compaction treatments were observed in bulk density and porosity of soil. Numerically, 22% increase in soil bulk density and 19% reduction in soil porosity were recorded due to the effect of two passes of the examined machineries over the field terrain comparing to the non-traffic treatment. Moreover; soil sampling at 0-10 cm and 20-30 cm depths resulted in the highest and the lowest soil porosity respectively. Keywords: epeated traffic passes, silage harvester, soil compaction, soil physical damage, soil porosity Journal: Research in Agricultural Engineering Pages: 136-140 Volume: 59 Issue: 4 Year: 2013 DOI: 10.17221/2/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/2/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201304-0004.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:4:id:2-2013-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Brožek Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Soldering steel sheets using soft solders Abstract: The paper contains strength tests results of joints soldered using lead and leadless soft solders. For tests lead solders types Sn63Pb37, Sn60Pb40, Pb60Sn40 and Pb48Sn32Bi and leadless soft solders types Sn96Ag4, Sn99Cu1, Sn70Zn30 and Sn96Ag3Cu1 were used. As basic joint material steel sheet of 1.0 mm thickness and zinc-coated steel sheet of 1.0 mm thickness were used. The size of test specimen was 100 × 20 mm. Two sheets were always cleaned and jointed together. For heating the propane-butane plus air flame was used. The tested assemblies were loaded using the universal tensile-strength testing machine until their failure. At the tests the force needed for assemblies' failure and failure type (in the soldered joint, in the basic material) was recorded and the solder strength was calculated from the measured data. The test results show that for soldering of steel sheets as well of zinc-coated steel sheets of 1.0 mm thickness the joints soldered using the lead soft solder type Sn63Pb37 and the leadless soft solder type Sn96Ag4 were of the highest strength. Keywords: soldered joints, leadless solders, laboratory tests Journal: Research in Agricultural Engineering Pages: 141-146 Volume: 59 Issue: 4 Year: 2013 DOI: 10.17221/7/2012-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/7/2012-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201304-0005.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:4:id:7-2012-RAE Template-Type: ReDIF-Article 1.0 Author-Name: P. Hrabě Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic 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 Title: Research of overlays influence on ploughshare lifetime Abstract: The aim of this study was to research the impact of the overlaying to increase the resistance to the abrasive wear of the ploughshare using three types of welding tubular wire electrodes. These tubular wire electrodes are used to increase the active parts of machines and equipments processing the soil. The experiment was performed on the six ploughshare plough, where the first and last share was without the overlay. Overlaid shares were compared with non-overlaid shares as standards. From evaluation, it is clear that the best overlaying materials are FILARC PZ 6159, OK Tubrodur 14.70 and OK Tubrodur 15.82. The results proved that the wear of the ploughshare is increased towards the heel. The study determined the weight loss during the ploughing and ploughshares dimensional width. The research results did not confirm the benefit of the overlaying with regard to the ploughshare lifetime. Keywords: ploughing, soil, abrasive wear, overlaying, field tests Journal: Research in Agricultural Engineering Pages: 147-152 Volume: 59 Issue: 4 Year: 2013 DOI: 10.17221/3/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/3/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201304-0006.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:4:id:3-2013-RAE Template-Type: ReDIF-Article 1.0 Author-Name: I. Mašík Author-Workplace-Name: Department of Electrical Engineering and Automation, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Reliability of ZigBee transmission in agriculture production Abstract: Currently, the unlicensed ISM (Industrial Scientific and Medical) band 2.4 GHz has become saturated due many standards used at once. In agricultural production ZigBee has a lot of applications, from wireless sensors networks to complicated automation applications. This paper deals with improving the coexistence properties of ZigBee (IEEE 802.15.4), while keeping compatibility with the basic standard. This paper describes principles and application of forward error correction above the physical layer, consisting of block data interleaver and Hamming code, and also the effect of improvements in coexistence with variously loaded WiFi 802.11g. Keywords: dependability, Hamming, wireless, communication Journal: Research in Agricultural Engineering Pages: 153-159 Volume: 59 Issue: 4 Year: 2013 DOI: 10.17221/15/2013-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/15/2013-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201304-0007.txt Handle: RePEc:caa:jnlrae:v:59:y:2013:i:4:id:15-2013-RAE