Volume 20 (2016): Edizione 4 (December 2016)

Dissipation hypothesis of energy under cyclic loads conditions was used to characterize the behavior of berry fruit. The possibility of dissipation of energy as a result of plastic deformations (Dawidenkow hypothesis) or visco-elastic deformations (Voigt hypothesis) was considered. Tests of hysteresis of whole fruit squeezed among two rigid plates for various levels of load and with various speeds of deformation of samples for two directions of load application were conducted for verification of the usefulness of both hypotheses. The strength tests were preceded by the test of hysteresis, the mass and the geometry of fruit were determined additionally as well as conventional density and moisture was counted. A mutual relation of average values of the coefficients of elasticity E_C was accepted as the measure of dissipation of energy as a result of changes in the angle of inclination of the curve in the springy return phase. Voigt hypothesis was confirmed as useful within the range of small speeds of deformation and lack of usefulness of the Dawidenkow hypothesis was proved.

The objective of the paper was to carry out a bibliometric quantitative analysis of publications concerning the application of artificial neural networks in the research area - agriculture and a bibliometric quantitative analysis and subject analysis with regard to agricultural engineering. A number of scientific publications devoted to the ANN found in the data base of the Web of Science - in documents published to 2015 was a basis for the quantitative analysis. Research on the use of artificial neural networks in the research area - agriculture is extending systematically. Moreover, a rapidly growing number of citations prove a continuous increase in the scientists’ interest in possibilities of the ANN applications. The quantitative analysis of scientific publications in 5 selected scientific journals and thematically related to agricultural engineering (indexed in the Web of Science) allowed a statement that 236 scientific articles from 1996- 2015 were related to the ANN application. The biggest number of publications was reported in Computers and Electronics in Agriculture - 118 articles. In 2011-2015 there was a growing trend in dynamics of publishing of scientific papers devoted to the ANN application to agricultural engineering. Thus, we may assume that the research related to application of the artificial neural networks to agricultural engineering will be continued and their scope and number will be still growing. The thematic analysis of the most often quoted publications from 2011-2015 in the journal Computers and Electronics in Agriculture, proved that they concern both the issues related to the classification problem as well as to modelling processes and systems. We should suppose that the subjects related to modelling of drying processes and application of neural networks for image analysis will grow dynamically in the following years.

The objective of the research was to create a model which defines the relation between a fundamental contact area of a seed and the pressure force, water content in a seed and its geometrical dimensions with application of artificial neural networks (SSN). Computer program Statistica Neural Networks v. 6.0. was used for formation of a neural model. Tests were carried out on Roma wheat seed and Dańkowskie Złote rye with six various water contents: 0.11 0.15 0.19 0.23 0.28 0.33 (kg·kg^-1 dry mass). Caryopses were loaded with eight values of compression force - from 41 N to 230 N. Multiplicity of iterations was 5. Seed material was moistened to obtain a specific water content. Each seed was loaded with compression force with respectively growing values: 41N, 68N, 95N, 122N, 149N, 176N, 203N and 230N. A four-layer network of Perceptron type with 10 neurons in the first and 8 neurons in the second hidden layer was selected as a model which the best defines the contact area of grain seeds loaded with axial force at various moisture levels. This network has 4 inputs (water content, pressure force, thickness and length of caryopses) and one output (elementary contact area of rye and wheat seeds). Comparison of the neural model with empirical formulas obtained from nonlinear estimation proved a considerable higher precision of the first one.

The impact of biomass addition to the RDF oversize fraction on quality parameters obtained from this blend of briquettes produced under semi-industrial conditions was analysed. For the purposes related to the experiment four RDF mixtures with fragmented biomass of common willow Salix viminalis L., differing only with percentage participation of base elements, were prepared. The briquetting process was performed with the use of a semi-industrial briquetting machine at the determined compaction pressure of 47 MPa and a diameter of a sleeve (and a briquette at the same time) of 50 mm. Selected quality parameters of produced briquettes were determined, i.e. density, mechanical strength DU and compression strength. The best parameters were obtained for briquettes produced from the blend with a 50% share of willow (ρ=843.9 kg · m^-3, DU=86.1%, R_c=0.46 MPa). The lowest parameters were in case of briquettes without biomass addition. Statistical analysis of research results indicates that biomass additions to RDF significantly affect the improvement of quality parameters of the obtained briquettes.

Short review of grassland restoration techniques has been made with emphasis on the application of newly developed wide-strip overseeding aggregate. Machines currently available on the market are not suitable for all types of soil and grassland conditions. Vredo seeder is useless on muck soils, while Moore aggregate requires herbicide application. Therefore it is not to be applied in organic farming. Construction designated in ITP Kłudzienko (wide-strip overseeder) is a very economical and effective, possible to be used also on muck soils and without assistance of any chemicals. Operation of the machine consists of ‘milling’ of wide (about 10 cm) strips of sod and overseeding of mineral fertilizers and seeds of grasses, legumes and herbs. Cultivator for soil ‘milling’ strips is driven by the tractor PTO. By changing the spacing of strips, an oversown area can be resized from 20% to 40%. The effect of overseeding, evaluated next year exposed the increase of hay yield from 0.8 to 1.2 t · ha^-1 of dry matter in the first cut. Such innovative construction is particularly important in dairy farms which are in the need of the best quality feed.

The paper presents main provisions of methodology of manure utilization systems evaluation. All costs, starting with the costs related to manure cleaning in premises to the costs of increasing the biological yield obtained from its use, including the soil fertility value changes, were considered. The target function is offered a minimum of complex costs of entering the required amount of nutrients and organic matter per unit area for the planned yield. The effective technical solutions of calculations based on the proposed method include: construction of a boom conveyor with a hydraulic drive and described performance, scraper and screw types of conveyors, automatic scraper loading installation of manure from livestock buildings. The proposed solutions will reduce losses of nutrients by 50-70%, and will allow production of 20 million tons of grain annually.

A condition of obtaining compost with proper sanitary parameters is achieving the organic recycling process temperature which exceeds 7°C. The objective of the paper was to determine the temperature course in the compost tank for organic recycling of dead poultry in relation to the applied structure forming material. Wheat, oat, barley, rapeseed and corn straw were used as a structure-forming material. A measuring system was equipped with a probe with a temperature sensor with precision of ±0.15°C, transducer and data recorder. Results were prepared with the use of the analysis of variance at the level of significance of α=0.05. Statistically significant differences of the temperature value in the thermophille phase of the composting process between combinations of the experiment were indicated. In all investigated combinations of the experiment, achievement (or exceeding) the temperature value of 70°C of the compost mass was reported.

The aim of the research was to determine how time of infrared radiation heating of grains influences the falling number of flour gained from wheat variety Waluta and spelled wheat variety Schwabenkorn. Moisture content was determined in the first stage of the study and it was 12% ± 1%. Then grain was moisturized to the moisture of: 14, 16 and 18%. Prepared material was subjected to infrared radiation heating at the temperature of 150°C for 30, 60, 90 and 120 seconds. The heated material was sent to milling, and the falling number was determined. It has been found that the infrared radiation heating of wheat grains prior to milling significantly affects the falling number of flour, which increases with the duration of heating grain.

In order to support the designing process and selection of subassemblies of an installation, specialist application programs are created. Selected applications were compared in the paper through their use for designing hypothetical solar collector systems for a single family house with a varied number of household members. With the use of particular applications, calculations for the same input assumptions were made. Results obtained with the use of a traditional calculation method were a reference point. Applications were compared on account of the type and amount of input parameters which may be introduced, type and number of determined values and their value. Based on the obtained results usefulness and scope of use of an application were assessed.

The article presents calculations of unit fumes emission made based on the measurements of the fumes composition during a load test. The test was carried out with the use of a movable dynamometric stand adjusted for testing agricultural tractors by power take-off shaft. Calculations of unit emission were made based on the assumed flow of air sucked by an engine and the measured composition of fumes emitted during the load test. Results of tests and analyses supply information on the mass of particle matter and the selected gas elements emitted by an engine working under the load which was related to simultaneous determination of the exploitation characteristic of an engine. The presented methodology may be helpful at evaluation of impact of farm tractors on the environment within the hazardous fume components emitted by them.

The paper, based on the materials of the Main Statistical Office, presents a present state of use of renewable energy sources in the Polish power industry. Moreover, based on the available data, the amount of energy used for roofed production was estimated (heat, electric energy). Additionally, the amount of emission to atmosphere of hazardous substances (sulphur oxides, lead oxides, carbon dioxide and carbon oxide, dust and benzo(a) piren) was determined. Based on the available literature, technical solutions, which are analysed in various scientific centres, which aim at decrease of fuel consumption, were presented. A detailed analysis focused on the possibility of substituting fossil fuel with another heat source, effectiveness of energy use, increase of insulation ability of the facility roof and modification of greenhouses structures. From among the available energy sources, problems and its possible use in horticultural production were presented. The following energy sources were analysed: geothermal energy, sun and wind energy, biomass, heat pump; co-generative system (triple co-generative). Also barriers and possibilities of use of own boiler house and heat from central heating grid as energy source were analysed.

The paper presents the results of analysis which enable determination of the value of the pressure losses coefficients which occurred during air suction and flow through a perforated pipe. Knowledge on them is indispensable for determination of regularity of air suction along the considered pipe. Exiting the basic energy equation, firstly a local coefficient of pressure losses was determined and then the form of the relation for its determination in the function of independent variables was found out. In the second stage, the value of pressure losses caused by mutual crossing of two streams (axial stream and stream sucked by the side surface of a pipe) was determined. Also, for this coefficient, the form of the correlation equation including power relation between the independent variables was emphasised. The calculated values of the discussed coefficients from determined forms of correlation equations are satisfactorily compliant with the calculated values from the experiments which were carried out.

The objective of the paper was to determine the work expenditures and costs of eradication of an energy willow plantation with currently applied mechanical methods and with the use of the test model of a machine for cutting willow rootstocks as a part of the scientific project no. PBS2/A8/26/2014. The scope of the paper covered research for four machine units constructed for a twelve-year willow plantation with the surface area of 3 ha. Work inputs for eradication of the plantation of the investigated aggregates were within 8.1 to 50.4 mhr ∙ ha^-1. Work inputs with the new machine were 22.3 mhr ∙ ha^-1. The level of work inputs was influenced by low working speeds of the tractor-machine unit and working speeds from 0.4 to 2.3 m. Costs of willow plantation eradication with current mechanical methods were from 4302 to 15536 PLN ∙ ha^-1, and with the use of the new machine it was 5457 PLN ∙ ha^-1.

The objective of the paper was to present straw pellets production technology and to determine their production costs. The paper presents also the cost structure and economic effectiveness of pellets production. Tests were carried out in EKO-BIOMASA company which produces pellets. It is located in Biechów in Świętokrzyskie Voivodeship. Unit costs of pellets production were: 310.20 PLN ∙ t^-1 for option 1, 285.40 PLN ∙ t^-1 for option 2 and 278.90 PLN ∙ t^-1 for option 3. The most favourable was option 3 when the pellet production was carried out on the technology line in the 3-shift system day and night. In all three variants of pellet production, the highest costs were in case of electric energy. Its participation in the cost structure in relation to the option was within 42% (option 3) and 38% (option 1). The obtained indicator of economic effectiveness for all the investigated options was higher than one.

Technology of processing of agricultural raw material and production residues from agri-food industry often requires their dewatering. Digestate is one of such materials i.e. the mass remaining after the bio-gasification process, which has great hydration (above 85%). The objective of the research was to know the impact of dewatering on the change of water content in digestate from biogas in Piekoszów. A mechanical dewatering process was carried out and reflected the conditions of operation of screw presses for dewatering of plant raw materials, whose screen internal diameter is 160 mm. Knowing the impact of pressure on the dynamics of raw material moisture decrease will allow modelling of the operation of industrial devices with similar operation parameters. Thus, a research on the dewatering process with the use of pressure within 0.58-2.91 MPa and slotted screens with meshes size of 0.1; 0.2 and 0.3 mm were carried out. The analysis of the obtained results indicates that an effective process of dewatering of the investigated digestate takes place at the working pressure to 1.74 MPa regardless the applied screen. Further increase of pressure does not cause a significant decrease of moisture in the investigated material.

In case of traditional harvesting methods the losses of perennial grass seeds may reach 45-50% of the biological yield in unfavourable weather conditions. The paper presents the results of comparative assessment efficiency of various methods of harvesting of perennial seed grass. It was found that the use of special devices and structures in combine harvesters allows increase of yield of technological mixture to the combine tank, degree of seed threshing to 93% and limit the losses of crop to 20-29%. Harvesting of seeds in non-waste technology with harvesting of the entire yield with later transport, drying, threshing and seeds cleaning in stationary devices results in reduction of losses by 5 to 10% but it leads to the increase of energy inputs by 24-25% in comparison to traditional with threshing method. Harvesting with a combing method of plant seeds on a trunk in „Невейки” technology results in the increase of the seeds harvesting to 86-98% of a biological yield.

In recent years systemic changes in waste management have affected searching and implementation of solutions that increase waste recovery including those intended for recycle. The article presents a predicted amount of municipal waste intended for recovery based on their selected streams. For the needs of a conceptual solution the area was determined, which was operated by the mentioned installation. The paper uses the indicators of waste accumulation: mass, volume, bulk density and irregularity of their collection in 2011-2013 for determination of the sorting plant efficiency. Elements of the installation, which should enable optimization of the waste recovery process optimization, were selected. Moreover, frames of technological efficiency of the suggested solution were defined. The aim of the paper was an attempt to select parameters of a municipal waste sorting plant with location under conditions of Stary Sącz city.

In this study the influence of selected factors, such as duration of water sorption resulting from the process of reducing sugars elution from semi-finished products, temperature of sorbed water, frying temperature and size of the studied objects (thickness of slices), on the total fat content in dry mass of the obtained products was analyzed. The study was conducted on Innovator cultivar. The scope of the study encompassed 5, 10, 15, 20 min water sorption linked to the process of reducing sugars elution. A control study was also conducted on samples without the process of reducing sugars elution. Temperature of sorbed water was 20 and 40°C; temperature of slice frying was 140 and 180°C; the size of the studied objects, in the experiment limited by the thickness of slices, was 4 and 9 mm. Determination of the total fat content in the products was conducted using the Soxhlet method. The greatest amount of fat in dry weight was contained in the products from samples in which sugars were not eluted, when the process was conducted for a short period of time (several minutes) or when elution continued for the longest period of time, approx. 20 min. The smallest amount of fat was contained in the products from samples in which the immersion in water was conducted for 10-15 min. Thicker slices absorb smaller amounts of fat. Increase of temperature of sorbed water in the process of extracting sugars from semi-finished products results in the increase of the total fat content in dry weight of products.

The article presents the procedure of determination of a structural form of an agricultural machine which encompasses methodological aspects of design related to the division of the basic objective function into member functions, multi-variant solutions and synthesis of astructural form (a virtual prototype of an agricultural machine). The suggested course of proceeding was presented by the case of a design of a tunnel spraying machine. This example reflects well and includes the specificity of the design object in the form of an agricultural machine with specific technical and agro-technical requirements. Attention was paid to the aspects related to methodology of selection of fractional solutions based on previously defined criteria.

The paper presents the results of research, the objective of which was to determine the impact of particle size distribution and density of digestates and ash on density and tensile strength of granular fertilizer obtained from mixtures of these substrates. Particle size distribution, absolute density, envelope density and porosity of substrates were determined. Granular fertilizers were made of clean substrates and their mixtures. Envelope density of the obtained granulates was within 0.81 - 1.88 g⋅cm^-3. The determined compaction degree was within 3.65 - 10.12. While, the compaction index IS of granulates made of mixtures was within 0.5 - 0.55 and was lower in comparison to IS of granulates from digestates (0.6) and ash (0.76).