Research in Agricultural Engineering, 2017 (vol. 63), Special Issue
Review of energy potential of the wood biomass of orchards and vineyards in the Czech RepublicOriginal Paper
Patrik Burg, Vladimír Mašán, Martin Dušek, Pavel Zemánek, Kazimierz Rutkowski
Res. Agr. Eng., 2017, 63(10):S1-S7 | DOI: 10.17221/30/2017-RAE 
The most important sources of biomass energy are currently coming from agricultural activity. A sizeable portion in production areas is waste wood after the winter cut of orchards and vineyards, which cover areas exceeding 30,000 ha in the Czech Republic. The most important are species like apples, peaches, apricots, plums, sweet cherries, sour cherries and grapevines. Average production of wood mass for individual species of fruit trees and grapevines ranges from 1,540 kg/ha up to 6,762 kg/ha, i.e. 1.5 t/ha to 6.8 t/ha. The calorific value for these species ranges from 14.70 to 16.39 MJ/kg, with moisture between 6 and 8%. The results show that the...
Automatic guidance systems in agricultural machinery as a tool for drivers' mental strain and workload reliefOriginal Paper
Zděnek Kvíz, Milan Kroulík
Res. Agr. Eng., 2017, 63(10):S66-S72 | DOI: 10.17221/53/2017-RAE
This article evaluates agricultural operator´s stress, mental strain and generally fighting with driving difficulties during operating agricultural machinery sets by means of a heart rate indicator. Different drivers driving different tractors with implements were chosen and evaluated during different field jobs, namely soil tillage and sowing. Machinery position on the field was precisely monitored by a GPS receiver and the heart beat rate was observed by means of a chest belt special device with a heart rate sensor. The output data from the sensors were monitored during conventional manual steering of the tractor-implement set and also when using...
Technological and economic evaluation of manure production using an activator of biological transformationOriginal Paper
Petr Šařec, Oldřich Látal, Petr Novák
Res. Agr. Eng., 2017, 63(10):S59-S65 | DOI: 10.17221/50/2017-RAE
The aim of this paper was to verify the effect of the Z'fix (PRP Technologies, France) activator of biological transformation of manure from the viewpoint of the cowshed conditions parameters, produced manure quality, manure application effect on crop yields, and overall economics. Concerning manure production, the application of the Z'fix agent enhanced quality, structure and nutrient content (N total by 23%, P2O5 by 42%, K2O by 17%) in the manure from deep litter housing. Compared to the untreated control, differences in the nutrient content of N total and K2O were statistically significant, NH3...
Experimental determination of poplar (Populus nigra L.) wood drying curvesOriginal Paper
Jiří Souček, Milan Kroulík
Res. Agr. Eng., 2017, 63(10):S53-S58 | DOI: 10.17221/46/2017-RAE
Fresh plant material is degraded quickly and very easily. A possibility to avoid its degradation is drying. Drying is an energy-intensive operation and reducing of energy consumption means improving the energy balance and the economy of production. An important indicator of drying efficiency is the relative rate of drying. Curves of the relative drying rate for poplar (Populus nigra L.) wood were determined in an experimental oven. Freshly harvested samples were compared to samples of poplars that were stored between March and December on an outdoor uncovered area. The rate of stored wood drying was higher in comparison with fresh wood under...
Translocation of the upper soil layer in multiple operations of seedbed preparationOriginal Paper
Petr Novák, Josef Hůla
Res. Agr. Eng., 2017, 63(10):S46-S52 | DOI: 10.17221/40/2017-RAE
Translocation of tracers incorporated into the upper layer of topsoil was evaluated in the course of seedbed preparation for winter wheat. Aluminium cubes with the edge length of 16 mm were used as tracers that were placed into the soil before its tillage into furrows perpendicular to the direction of passes. After the passes of the OPALL-AGRI combined cultivator, the tracers were searched and marked using a metal detector. The translocation of tracers was evaluated during multiple passes on flatland and on the slope. During the seedbed preparation on the slope, downslope and upslope passes in a fall line direction were chosen. Results of the tracers...
Changes in soil properties due to the application of activators in conditions of very heavy soilsOriginal Paper
Petr Šařec, Petr Novák
Res. Agr. Eng., 2017, 63(10):S40-S45 | DOI: 10.17221/39/2017-RAE
This paper deals with verification of the effect of fermented manure (with and without Z'fix activators) and soil activators (PRP Sol) on a soil properties change. Their application should lead to a change in physical, physical-chemical and biological properties of soil, along with ecological material fixation, improved water retention and infiltration, reduction of soil susceptibility to water erosion and decreased soil tillage energy requirements. Field trial was established in Sloveč in Central Bohemia in the year 2014. The experiment was divided into several variants and was designed as multiannual. Z>fix activator was used as a biological transformation...
Comparison of logistic, energy and exploitative parameters of compost and manure application by spreadersOriginal Paper
Jiří Souček, Radek Pražan, Amitava Roy, Petr Plíva, Antonín Jelínek, Jiří Vegricht
Res. Agr. Eng., 2017, 63(10):S33-S39 | DOI: 10.17221/37/2017-RAE
This article deals with comparison of composts and manure use from the viewpoint of handling, transport and application on agricultural land. The published values were established by measurements under working conditions and afterwards converted on the basis of the content of nutrients defined in laboratory. Compost contained a greater share of nitrogen, phosphorus and potassium and had higher dry matter content and lower volume weight. Direct consumed energy expressed by recalculation of the consumed diesel fuel in case of composts moved from 5.12 MJ/kg (potassium) up to 16.19 MJ/kg (phosphorus). In case of manure it was higher and moved from 10.49...
Parameters of the drying medium and dried hops in belt dryerOriginal Paper
Adolf Rybka, Petr Heřmánek, Ivo Honzík, Karel Krofta
Res. Agr. Eng., 2017, 63(10):S24-S32 | DOI: 10.17221/35/2017-RAE
An important factor in hop growing is the process of drying. For this purpose belt dryers with follow-up conditioning are the most widespread but they are not ideal. In this respect, an analysis of the drying process was carried out in the belt dryer of Agrospol Velká Bystřice Co., Ltd. for the 'Saaz' hop variety. Drying parameters were monitored by means of fixed sensors, continuously sensing data loggers and samples taken for laboratory analysis (hop moisture, alpha and beta bitter acids, Hop Storage Index (HIS). The process of drying showed that hops are practically dry (10 ± 2.0% of moisture) already at the end of the second belt or possibly...
Dielectric properties of hops - an effect of bulk densityOriginal Paper
Jakub Lev, František Kumhála
Res. Agr. Eng., 2017, 63(10):S18-S23 | DOI: 10.17221/34/2017-RAE
Continuous detection of basic physical properties of freshly picked and cleaned wet hop cones would be very helpful for better control and automation of harvesting processes. That is why the main aim of this article was to determine the effects of bulk density changes on dielectric properties of freshly picked hop cones. Relative permittivity and loss factor were measured using a newly developed capacitance measuring device. A strong linear correlation between fresh hops relative permittivity and bulk density was found. This finding could be used e.g. for consequent hop drying process control. Significant differences between tested hop varieties were...
Low-cost infrared sensor for wildlife detection in vegetationOriginal Paper
Jakub Lev, Vadym Shapoval, Jan Bartoška, František Kumhála
Res. Agr. Eng., 2017, 63(10):S13-S17 | DOI: 10.17221/32/2017-RAE
The protection of wild animals from mutilation or being killed during haymaking is still a serious problem connected with high working speeds and widths of modern harvesting machines. That is why the main aim of this study was to test low-cost, high-speed and low-noise infrared array sensor Melexis MLX90621 for the application of wildlife detection with the potential to be used in front of the mower equipment. The tests with two different crops with or without a hidden dog were made. Results showed that the sensor is able to detect an animal hidden in the crop with very high probability. Nevertheless, direct sunlight conditions can cause the problems...
Effect of chopped maize straw on the quantity and quality of biogas producedOriginal Paper
Tomasz K. Dobek, Petr Šařec, Paweł Kołosowski, Ondřej Šařec
Res. Agr. Eng., 2017, 63(10):S8-S12 | DOI: 10.17221/31/2017-RAE
The increase in production costs of maize silage intended for biogas has led the producers to look for alternative sources of raw material. One of such materials is straw of agricultural crops, including maize. The use of lignin-cellulose materials, such as straw, by bacteria in a biogas fermenter is limited by its polymer structure. Therefore, it is required to process the straw before it is introduced into the biogas fermenter, which may allow to increase the biogas potential of straw. The simplest way of straw processing is its chopping. On the basis of the obtained results, it can be said that cutting the straw did not help increase the amount...