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The paper presents the results of a conceptual study of lightweight wooden construction hall building with polygonal ground plan, suitable for agriculture. It comprises evaluation of chosen technical and functional characteristics and possibilities for animal production. The results of the study confirm advantages (mainly lower material and costs demandingness, environmentally friendliness, light-weight construction, fast assembly operations) and disadvantages (mainly larger range of groundwork, higher demandingness on roof structure, foundation of slab constructions and anchoring of vertical bearing constructions). Values of radial tensile stress at an interval of 9.0 to 21.0 MPa and tangential tensile stress at an interval of 1.4 to 16.0 MPa were calculated on vertical load 100 kN at the top of the construction). The construction makes possible to achieve a span as far as 60 m with effective canvas strain at large radius curvature from 80 m to 100 m.

The contribution contains results of bonded joints strength tests. The tests were carried out according to the modified standard ČSN EN 1465 (66 8510):2009. The spruce three-ply wood of 4 mm thickness was used for bonding according to ČSN EN 636 (49 2419):2013. The test samples of 100 × 25 mm size were cut out from a semi-product of 2,440 × 1,220 mm size in the direction of its longer side (angle 0°), in the oblique direction (angle 45°) and in the direction of its shorter side (crosswise - angle 90°). The bonding was carried out using eight different domestic as well as foreign adhesives according to the technology prescribed by the producer. All used adhesives were designated for wood bonding. At the bonding the consumption of the adhesive was determined. After curing, the bonded assemblies were loaded using a universal tensile-strength testing machine up to the rupture. The rupture force and the rupture type were registered. Finally, the technical-economical evaluation of the experiments was carried out.

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.

The paper is aimed at pointing out possibilities of using of dendromass for heating. The object of interest was heating of housing units with 75.27 m² of total area. The average value of dendromass moisture was 17.71%. The inserted fireplace Nordica Focolare 70 with a nominal output of 9 kW was used as a heat source. For temperature measurement, a non-contact infrared thermometer GM 900 was used. The total heat loss transferred through walls of housing unit (heat loss through thermal bridges and ventilation losses) were calculated at the value of 176.26 W/K. Based on the results of samples moisture the net calorific value of one kilogram of burned fuel wood was determined (14.791 MJ kg). The amount of thermal energy which is necessary to supply by the heating system for the whole heating period was 14,199.18 kWh. The weight of raw fuel wood was 5,450.97 kg (at moisture of 30%), dried at 17.71% (4,636.87 kg). Price of raw fuel wood of acacia for the year under evaluation was 64.80 €/m³ (the required amount of raw fuel wood for heating period was 10 m³). Total costs for the heating season was thus 648 €. The price of heat transmitted by the fireplace inset Nordica Focolare 70 inserted into heating system using fuel wood (white acacia) with 17.71% of absolute moisture was 0.045636 €/kWh.

The effect of pre-processing conditions such as speed, die sizes and moisture content on durability of cassava flour was investigated. Densification of cassava flour was done by pelletizing the flour through die and it is necessary to determine optimum conditions for designing and constructing a suitable processing plant. The flour was mixed with water at different blend ratios to form cassava mash of different moisture contents. The pellet quality was evaluated in terms of the durability of the pellets against the moisture content of the mash (18, 20 and 22% w.b.), die size (4, 6 and 8 mm) and the screw speed (90, 100 and 120 rpm). Test results showed that maximum durability of 84.437% was recorded at 20% (w.b.) moisture content using 4 mm die and low durability of 61.26% with using 8 mm die at 18% (w.b.) moisture content. The durability result shows that it decreased with increase in die size. Statistical analysis revealed that the die size had significant (P ≤ 0.05) effect on the durability.

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 MJ/kg (nitrogen) up to 29.79 MJ/kg (phosphorus). The greatest share in energy consumption occupies transport, which was considered uniformly at the distance of 5 km. The study confirmed the feasibility of use of compost in agriculture as a partial substitute of conventional organic fertilizers; for its handling, transport and application the standard mechanization used for manure may be utilized.

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.

Agriculture is the sector that consumes by far most water globally. Much research efforts aim at minimizing losses through the use of drip irrigation. Rural agricultural areas often do not have access to a main electrical grid to power the pumps needed for drip irrigation; it reduces the options in paying for a grid extension, getting a diesel generator or investing in an off-grid renewable energy system. In this paper, these alternatives are assessed technically and economically under real world conditions through the Jordan Valley case study. The results show that the autonomous photovoltaic (PV)-battery system is preferable to the use of a diesel generator, as well as it is preferable to the main grid extension in many cases depending on the cost of grid electricity and distance from the grid. For current subsidized grid electricity retail price to farmers, the PV-battery system becomes more attractive above a 300 m distance from the grid, while if the actual cost of electricity production in Jordan is taken into account, then it breaks even to 128 m.

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 at the beginning of the third belt. It was also proved that hops are over-dried (moisture of 4 to 8%) and then they are adjusted by conditioning to the final moisture content of 8-10%. Excessive drying leads to cone disintegration, which makes any manipulation with hops for purposes of further processing difficult and results in greater losses of lupulin.

he column adsorption study examines irrigation water treatment prior to its application in order to ensure water-crop-consumer heavy metal transfer reduction to the safe level using locust bean husk char (LBHC) as biosorbent. Char structural pattern was investigated with SEM-EDX machine. Contaminated surface water was introduced simultaneously into the bioreactors containing 100 and 200 g of LBHC and collected after 30, 60, 90 120 and 150 min of detention time. Removal efficiency, isotherm and kinetic sorption model were the evaluation tools for the study. Percent of Cr, Cd and As removal at 150 min retention time were 83.33, 100 and 100%, respectively for 100 g biosorbents. A similar trend was observed for Cr and As removal at the same retention time for 200 g of LBHC. Metals sorption conforms to the Freundlich isotherm with correlation coefficient values greater than 0.92. Experimental kinetics had a good fit for pseudo second order (R² > 0.94 for most cases). Removal efficiency is a function of contact time, biosorbent dosage and metal concerned. Locust bean husk char has good and effective treatability for some heavy metals in mildly polluted water.

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 emissions dropped significantly by almost 35%. The economic benefit of manure production with the use of the Z'fix agent demonstrated overall savings at the level of 1,369 CZK/LU/year. The influence of manure produced combined with the PRP Sol application was tested in terms of a boost of crop yield potential of silage maize and of winter wheat. Compared to the control, both crops reached yields higher by 0.7% to 9.8%.

The proposed research paper analyses power consumption in grinding rolls of a flour mill. The observed mill has 15 grinding passages. The hourly efficiency of grinding roll on the first passage is 3,006.72 kg/h. The specific power consumption of individual grinding rolls ranges from 4.955 to 24.26 kWh/t. The thesis also contains results of research of grinding effects on grist. The greatest effect on grist was observed on the first grinding passage, where particle size after grinding was only 12% of the original grain size, as determined by sieve analysis. On the second through fifth passage, it was 85 to 96% (or 78 to 85% with shelling) of the original size. It was discovered during scouring that, in some cases, the sieve size of particles after grinding increased from 101 to 104% of the original size. This is due to shear force causing trituration of grist.

The paper deals with the determination of the oxygen permeability and mechanical properties of butter and curd aluminium paper foils Radaflex applied in the food packaging. Foil Radaflex is a paper foil covered by the aluminium layer. The measurement of the oxygen permeability was realized according to the Standard STN EN 77 0333. The measurement of mechanical properties was realized according to the Standard STN EN ISO 1924-2. Determination of moduli of elasticity in the longitudinal and transversal direction were provided and tensile properties as maximal elongations, maximal tensile forces, tensile strengths, tensile indexes and strain at breaks of the longitudinal and transversal specimens were evaluated. The permeability of pure oxygen through aluminium paper foils was studied. Aluminium paper foil was not permeable for the oxygen.

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.

Hydrothermal carbonization is one of suitable methods for energy recovery of sewage sludge and meat and bone meal. The task of the article is to determine appropriate hydrothermal carbonization process conditions and their impact on the quality of the final product - so called biochar or hydrochar. Parameters of the two main phases - initiation and polymerization - were monitored. The basic fuel properties of the final solid products of hydrothermal carbonization were determined. To produce biochar by hydrothermal carbonization, multifunctional pressure vessel with accessories was used - a batch reactor BR-300. Process parameters of hydrothermal carbonization confirm the effect of increasing temperature to increase the lower heating value (LHV). Neither calorific values of meat and bone meal (17.22 MJ/kg), nor calorific values of digested stabilized sludge (12.14 MJ/kg) showed a significant increase after undergoing processing. The effect of reaction temperature on the LHV of the final product is significantly higher than that of residence time. The results show that the main factor affecting LHV of the fuel sample is the final amount of ash. Unlike the meat and bone the hydrothermal carbonization of the stabilized wastewater sludge is one of the effective processing methods for subsequent energy use.

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.

The paper deals with gaseous emissions generated in biomass combustion in water boilers. It provides results of analyses of gaseous emissions and boiler efficiency in combustion of branches of apple trees from spring pruning, spruce cuttings and corn cobs obtained from kernel harvest. Measurements were done in laboratory conditions. Average CO emission values observed in combustion were from 334.7 to 650.18 mg/m³ and average NO_x emission values were low, between 50.1 and 157.2 mg/m³. Boiler efficiency in applewood combustion was lower - this was caused by its higher moisture.

The sensitivity analysis of key operating parameters on the average annual sub-profit in a group of three combine harvesters operating in companies providing agricultural services were analysed. Based on the results of the cost analysis, the following key operating parameters with the greatest influence on the costs were identified: the purchase price of the machine, the price of fuel, maintenance costs, personnel costs and annual performance. These parameters were used in the sensitivity analysis to investigate their effect on unit costs. Changing the above-mentioned parameters is calculated within ± 30% from their mean value. To perform a sensitivity analysis of the average annual sub-profit of combine harvesters, the unit price of mechanized work was additionally used. The results showed that greatest impact on both the average annual earnings of combines operation and on the changes in unit cost was those of the annual performance of the combine harvester, combine harvester purchase price and the cost of fuel. On the other hand, maintenance and personnel costs had a smaller influence concerning these changes of parameters.

The paper deals with the possibility of appropriate measurement and evaluation of emissions of nitrogen oxides. Development of exhaust systems which captures the solid particles emitted from engine, lost an objective assessment of the emission status of the diesel engine of agricultural tractor. Therefore, it is necessary to find a new method of measuring and quantifying the emission state of the diesel engine by measuring emissions, which should be economic and time-saving, but especially universal and sufficiently precise. The selected method should also provide sufficient information on such emissions that are subject to approval but they are not controlled during periodic checks.

Grain size distribution of grist is dependent on the type of grinding mill. The most widely used crushers used for malt grinding are roll grinding machines and dispersants are the disc mills. For rating of grist fineness grists made in the two-roller mill KVM 130/150 and dispersant the disk mill Skiold SK 2500 was used. The selected types of barley malt were processed: light malt, Munich malt, caramel malt and colouring malt. Rating of malt grist fineness was made with a help of sieve analysis using a "Pfungstadt sifter". Conclusions from the measurements are as follows: by using the two-roller mill the coarsest grist is got from caramel malt and the finest malt from the light malt. The dispersant was processing grist at a speed of 1,500 rpm and 2,800 rpm. For each speed, the coarsest grist was obtained from caramel malt and the finest grist was obtained by crushing colouring malt.

In this article, the effect of increasing dry matter content and reaction time of hydrothermal carbonization on mass yield of biochar was studied. Carbonization took place in batch experiments in a pressure vessel. Results have confirmed the assumption that the mass yield of biochar would increase with growing dry matter content in the initial solution and also with reaction time at reaction temperature of 200°C. It was found that components of the liquid product that remain in the biochar have a measurable impact on its mass yield. Mixing of the reactor proved to have a considerable effect on the mass yield as well. Biochar produced in absence of mixing had higher pore volume and higher yield. This was evident even after subtracting the equivalent liquid phase dry matter in the biochar after drying.

The contribution deals with the analysis of claddings quality realised by shielded metal arc welding with covered electrodes. For cladding, covered basic electrodes marked as E Z Fe 8 EN 14700 and E Z Fe 15 EN 14700 were used. The third type of electrode was experimentally made basic electrode with operating name EW11 (wolfram content 11%). New share made of C50R EN10083/1-98 was used as reference material. Quality of repairing deposits was evaluated by micro hardness measuring and by metallographic analysis of claddings and base material. Wear resistance of claddings was determined by weight loss during abrasive wear test by wading in following loose abrasive agents - Al₂O₃ (corundum), crushed rock and arable soil.

The paper deals with determination of oxygen permeability of the polyethylene and polypropylene foils applied in mulching and food packaging. The construction of the equipment of measurement of gas permeability through the foils is discussed. The design and construction of the equipment was realized with applying of the Standard STN EN 77 0333. The measurement of permeability of oxygen through the polyethylene Bralen 2-63 with 9% colored concentrate Maxithen HP 533041 - violet foil, Polyten®MLB black&white foil and black polypropylene nonwoven fabric foil were realized by means of the modified method.

The structure of the dry material plant is made up of a cell tissues system. The walls of the cells are formed by cellulose and lignin, ingredients difficult to biodegrade. Therefore, the aim of the breeders performed a variety of energy plants, providing a high yield of dry matter in the green state. This applies particularly to herbs, grown on agricultural and arable land (for example cereals, maize, sorghum, hemp, amaranthus, mallow, sugar beet, potatoes, fodder crops on arable land, permanent grassland and other). The subject of the experiment was to evaluate selected varieties of maize and sorghum and to determine the suitability of the materials on the device model for anaerobic fermentation mixed with beef slurry, and ferment from the biogas plant. Among the varieties of maize there are the significant differences in the production of biogas in the same conditions. Of the three maize varieties (Fixxif, Saxxo, Benicia), the most powerful was Saxxo.

The application rate of a nitrogen fertiliser is one of the most important factors that affect the nitrous oxide (N₂O) flux. Calk ammonium nitrate with 27% nitrogen content was spread by a fertiliser spreader VICON RS-L connected with a tractor Zetor 16145 and incorporated into the soil by a power harrow Pöttinger Lion 301 six hours after spreading. Monitoring points were selected based on the size of application rate 0, 100, 200 and 300 kg/ha and were measured 7, 14, 21 and 28 days after fertiliser application and incorporation into the soil. Nitrous oxide emissions were measured by a photoacoustic field gas monitor INNOVA 1412 with a multipoint sampler INNOVA 1309. Based on the data obtained, there were found statistically significant differences among time intervals and among the size of the application rate at a 95.0% confidence level. Results have shown impacts of the size of fertiliser application rate and time interval after fertilisation on nitrous oxide flux.

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.

The work is focused on description of tractor individual axels and wheels loading during ploughing. A combination of tractor inclination with force and momentum effects need not always result in marked differences in the load of driving wheels. This paper documents the relationship existing between forces working in the upper drawbar F_h of the three-point linkage and the momentum M_Tx. It was also demonstrated that with the increasing value of M_Tx the difference between loads of both rear wheels reduces. The described algorithm enables to evaluate output parameters of ploughing aggregates for different variants of forces changing in the tractor three-point linkage due to various ways of suspension and adjustment of individual plough types. When using data recorded in the course of ploughing operations it is possible to demonstrate the effect of plough adjustment/attachment on the efficiency of the whole ploughing aggregate.

Thin layer drying properties of high moisture garlic sheets under semi fluidized and fluidized bed conditions with high initial moisture content (about 154.26% d.b.) were studied. Air temperatures of 50, 60, 70 and 80°C were applied to garlic samples. Among the applied models, Page model was the best to predict the thin layer drying behavior of garlic sheets. Using this model, correlation coefficient (R²) was high for all drying cases. The computed values of D_eff were between 3.38 × 10^-10 and 2.54 × 10^-9 m²/s during the falling rate drying. Values of D_eff for garlic sheets were also increased with increasing in input air temperature. Activation energy values were varied between 51.32 and 60.58 kJ/mol for 50 to 80°C, respectively. The specific energy consumption (SEC) for garlic specimens was placed in the range of 0.316 × 10⁶ and 0.979 × 10⁶ kJ/kg from 50 to 80°C, respectively. An increase in air temperature caused decrease in SEC value. Application of semi fluidized bed convective drying with temperature between 50 and 60°C was suitable to produce dried garlic.

The article is aimed at verification of the effect of chaff length of fermented material and duration time of the contact of material with oxygen before dosing into the fermenter, on production and energy content of biogas. The results of the verification showed an effect of chaff length in the fermented material on production and energy content of the biogas at processing grass silage with high content of dry-matter and especially maize silage. When processing maize silage, optimal length of chaff in terms of production and energy content of biogas was 13 mm, with grass silage it was from 69 to 112 mm. Verification of the influence of time of grass silage and maize silage contact with air oxygen before dosing into the fermenter did not confirm our hypothesis. It was demonstrated that production and energy content of the biogas increase together with the length of duration of 7 days compared to fermentation of material after max. 3 h of contact with air oxygen.

The article discusses monitoring of the impact of tyre inflation pressure on tensile properties of forest tractors. The LKT 81 T forest tractor, manufactured byZŤS TEES, Martin (Slovak Republic) and widely used in Slovakia, was specifically chosen as the mechanised vehicle to be monitored. Tensile properties were examined using standard tensile tests, with a Tatra freight vehicle serving as the load vehicle. Actual measurements were performed on a concrete surface and on soil characterised as gravelly loam whose average moisture was 38%. The statistical methods used to verify the impact of significance from changes in tyre inflation pressure on selected tensile indicators were multi-factor analysis of variance (ANOVA) and Student's t-test. Even though statistical analysis failed to directly confirm significance in the impact of changes of tyre inflation pressure on selected load indicators for a forest tractor fitted with standard tyres, positive changes can be discerned in measured dependencies. The article concludes with a discussion of the results obtained and their possible application in operational practice.