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Abstract

Farm tractors due to the nature of their work are exposed to a substantial risk of failures. The issues of their reliability are unusually significant in the aspect of the time limit of realisation of agricultural works in agrotechnical seasons. Nowadays, tractors provided for agriculture have increasingly complex functional units. The aim of the paper was to analyse reliability of presently produced farm tractors. Three tractor makes were evaluated and the analysis of failures was carried out with regard to functional units. Based on the obtained results, the average time of correct functioning and refreshment times and availability of particular tractor makes were determined. It was stated that the obtained empirical data of the correct functioning time and refreshment time may be well described with exponential functions. Significant differences in the values that determine the average time of correct functioning and duration time of refreshment obtained by tractors of the investigated makes were found. From among particular functional units, electric and hydraulic systems were the most often damaged, regardless the tractor make.

Abstract

Results of laboratory tests on the sowing quality of Vistula parsley seeds with a working section of a seed drill by Weremczuk company Max Pneumatic S 156 model with a pneumatic sowing system were presented. Tests of the sowing section of a seed drill were carried out in laboratory conditions on a special stand. They showed that the seed drill speed and rotations of the sowing disc have a significant impact on the sowing quality expressed with participation of single, double sowing and passes. The most favourable results at all set distances between seeds in a row were obtained with a seed drill speed of 1 km·h−1. On the other hand, the increase of the working speed of a seed drill and rotations of a sowing disc influenced significantly the deterioration of the sowing quality.

Abstract

The chaff quality or, more specifically, the distribution of stalk length after straw shredding during wheat harvest with a combined harvester is of significant interest for ploughless tillage practices. The currently applied characterization methods (manual length measurement or the cascade sieve analysis) are time-consuming and labour-intensive. Image analysis-based size characterization has the potential to solve these problems. In this study, two techniques of digital image processing, the well-known method of image moments (rectangular model) and a sub-pixel skeletonization approach (flow lines-tracing), were applied comparatively for stalk length measurement. Upon applying the rectangular model, the analyzed stalks were found to be longer than when the flow lines-tracing algorithm was applied. This was attributed to the unbiased decision criteria of the measuring method. A greater length of the stalk is to be expected in the main stalk than when the length of a twisted or branched stalk is measured from the edge length of a rectangular box that encloses it.

Abstract

The paper presents the results of research on the mass and the energy potential of malting barley straw of the “Klas” variety. The research was designated on a 100 ha plantation located in Pojezierze Iławsko-Sztumskie region. Using the Yara N-Sensor processor, precise application of mineral fertilizers according to determined fertilization demand allowed increasing the grain yield by 26% and the straw biomass yield by 74% compared to the control sample. The resulting increase in bio-mass obtained in the form of straw impacts its possible partial use for energy purposes without negative effects on the environment. The tested energy value of malting barley straw as a function of moisture content allowed a conclusion that between 10 and 25% of water content the energy value drops from 13.1 to 7.4 GJ∙t−1. For an average water content of 15%, this yields an energy potential unit of 23.76 GJ∙ha−1. Following observations of the combustion process, it was concluded that barley straw cannot be used as a source of biomass for the large-scale power production since its ash melts at below 800ºC.

Abstract

It is justified that the problems related to changes in physico-chemical properties, concentration of trace elements in lubricat-ing oil and the impact of these changes and their dynamics on vehicle structural elements should be considered in detail. It is important that empirical data, theoretical relationships and test results should be taken into account. The paper presents re-search results of the selected physico-chemical parameters and the content of metals in samples of the used engine oil. The samples were collected both after the fuel system failure and during the operation of the farm tractor according to the date of changing engine oil assumed by the producer. An instrumental chemical analysis method HDXRF was used to determine chang-es of the content of trace elements Fe, Sn, Cu, Pb, P, Zn, Ca in engine oil. Additionally, changes in physico-chemical properties were determined with the use of FT-IR spectrometry. Courses of these changes were analysed on account of their impact on the utility properties of the engine oil.

Abstract

The study assesses the impact of the economic size of farms on the efficiency of their material and energy expenditure, based on 679 farms from the Lubelskie Voivodeship. The analysis was made for the years 2013-2015 and the farms were divided into six economic size classes. 5 indexes for the efficiency of material, energy and material-energy expenditures were calculated for all farms. The aim of the work was to select a group of farms with the highest efficiency of energy and material expenditure. It was found that economically small farms managed this expenditure most effectively, as evidenced by the highest values of 4 out of 5 analyzed indexes. Very small and medium-small farms demonstrated the highest efficiency of material expenditure. In contrast, energy expenditure was most efficiently used by medium-small farms. The farms that were the largest economically were characterized by the highest efficiency index of material and energy expenditure, calculated as the ratio of total production to the expenditure.

Abstract

The objective of the paper was to determine the impact of moisture and rotational speed of threshers on the process of crushing of lupine seeds. Raw material was led to four levels of moisture from 8 to 14% every 2%. The studies were carried out on the laboratory hammer mill with the use of variable speeds of mill hammers within 5500-7000 rot∙min−1. The studies that were carried out proved significant relations (p<0.05) between the analysed process variables and energy consumption and susceptibility of seeds to crushing. It was stated that along with the increase of the rotational speed, a reduction in the drop of the average dimension of particles of mill takes place. Along with the increase of moisture of lupine from 8 to 14% a unit energy of crushing increases on average by approx. 83%. It was proved that the susceptibility ratio of seeds to crushing increases along with the increase of raw material moisture. Such relations were determined for all investigated rotational speeds of hammers.

Abstract

Despite a long-term reduction trend, the potato production in Poland compared to EU countries is still very high. Therefore, the aim of the paper was to investigate the impact of mechanical damages and light for various genotypes on glycoalkaloids accumulation. Glycoalkaloids are toxic steroid glycosides that naturally occur in the family of Solanaceae. According to many authors, their presence in plants is related to resistance to a physiological stress inflicted by mechanical damages and infections caused by some microorganisms and insects. The TGA content above 200 mg∙kg−1 in a fresh mass of potatoes is an upper limit that guarantees health safety of food. Studies were carried out on 28 potato cultivars divided into 4 groups. The studies that were carried out after harvesting and after 5 months of storage in the experimental storage room in the temperature of 8°C showed an impact of damages and exposition to light of potato tubers on the content of glycoalkaloids.

Abstract

Modern livestock facilities necessary in the production of milk, meat or other animal products should be constructed with environmental protection in mind, while ensuring high quality of production and animal welfare. The high level of mechanization in modern dairy farms, including automated and robotic processes, allows obtaining high quality raw material (e.g. milk), and significantly increasing labor and production efficiency. In addition, the use of photovoltaic (PV) panels, heat recovery from milk and obtaining biogas from the manure fermentation process, contributes to large energy savings on the farm. Excess of natural fertilizers, which are an animal byproduct, can be used as a substrate for methane fermentation. The presented examples of obtaining renewable energy allow improving the economic efficiency of animal production. They also ensure appropriate environmental conditions through the innovative management of natural fertilizers.

Abstract

The aim of this work was to study the particle size distribution of micronized oat bran. An impact classified mill was used to pulverizing. Before the pulverizing raw material was sterilized using overheated steam at 150°C during 3.5 min. The moisture of bran after sterilization decreased from 7.2 to about 3.9%. Five speeds of the rotor disc were used: 2600, 2970, 3340, and 3710 rpm. For each speed of the rotor disc the following speeds of classifier wheel were applied: 480, 965, 1450, 1930, 2410 and 2890 rpm. The particle size distribution of oat bran layer was measured by laser light scattering. Moreover, the sense of touch of coarse particles of micronized oat bran on a tongue was assessed according to five point scale. The largest fragmentation of the oat bran was obtained at a disc speed of 3710 rpm and at a classifier rotation speed of 1930 rpm, whereas the most coarse particles were obtained when these parameters were 3340 rpm and 480 rpm, respectively. On the other hand, the highest uniformity in size of particles in size was observed when the lowest speed of disc and classifier were used. Moreover, for the most samples the pulverized particles of oat bran were almost not discernible on tongue.