Sugar beet fertilization is a very complex agrotechnical measure for farmers. The main reason is that technological quality is equally important as sugar beet yield, but the increment of the root yield does not follow the root quality. Technological quality implies the concentration of sucrose in the root and the possibility of its extraction in the production of white table sugar. The great variability of agroecological factors that directly affect root yield and quality are possible good agrotechnics, primarily by minimizing fertilization. It should be considered that for sugar beet, the status of a single plant available nutrient in the soil is more important than the total amounts of nutrients in the soil. Soil analysis will show us the amount of free nutrients, the degree of soil acidity and the status of individual elements in the soil so that farmers can make a compensation plan. An estimate of the mineralizing ability of the soil, the N min, is very important in determining the amount of mineral nitrogen that the plant can absorb for high root yield and good technological quality. The amount of N needed by the sugar beet crop to be grown is an important factor, and it will always will be in the focus for the producers, especially from the aspect of trying to reduce the N input in agricultural production to preserve soils and their biodiversity but also to establish high yields and quality.

Successful prediction of the relevant mechanical properties of steels is of great importance to materials engineering. The aim of this research is to investigate the possibility of reducing the complexity of artificial neural networks-based prediction of total hardness of hypoeutectoid, low-alloy steels based on chemical composition, by introducing the specific Jominy distance as a new input variable. For prediction of total hardness after continuous cooling of steel (output variable), ANNs were developed for different combinations of inputs. Input variables for the first configuration of ANNs were the main alloying elements (C, Si, Mn, Cr, Mo, Ni), the austenitizing temperature, the austenitizing time, and the cooling time to 500 °C, while in the second configuration alloying elements were substituted by the specific Jominy distance. Comparing the results of total hardness prediction, it can be seen that the ANN using the specific Jominy distance as input variable (runseen = 0.873, RMSEunseen = 67, MAPE = 14.8%) is almost as successful as ANN using main alloying elements (runseen = 0.940, RMSEunseen = 46, MAPE = 10.7%). The research results indicate that the prediction of total hardness of steel can be successfully performed only based on four input variables: the austenitizing temperature, the austenitizing time, the cooling time to 500 °C, and the specific Jominy distance.

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The aim of this study was to determine the influence of different pH values of water solution (pH 4.5, 5.5, 6.5, 7.5 and 8.5) and temperatures (10, 15 and 20 ºC) on fibre flax seed germination and seedlings morphological characteristic (seedling root and stem length and total seedling length). The study was conducted in the controlled conditions by rolled filter paper in 4 replicates for 7 days. The average germination rate of flax seed was 84%. The highest germination rate was found at 20 ºC (88%) which was very significant (P<0.01) as compared to germination rate at 10 ºC where it was decreased by 9%. The highest share of normal seedlings was determined at pH 5.5 (70%) and the lowest at pH 8.5 (59%).There was no statistically significant influence of different pH on morphological characteristic of fibre flax seedlings (seedling root and stem length and total seedling length). The statistically significant difference (P<0.01) was determined in the length of the seedlings depending on the temperature, whereby after 7 days the largest seedlings were developed at 20 ºC (14.4 cm) and the shortest at 10 ºC (2.1 cm). In general, the lowest pH value (4.5) as well as the highest pH value (8.5) in this study resulted in a lower share of normal and healthy seedlings (63% and 59% respectively) and compared with seedlings of other pH values they developed a smaller root and stem.