Mechanization in agriculture & Conserving of the resources
Vol. 63 (2017), Issue 6

Table of Contents

  • MECHANIZATION IN AGRICULTURE

    • CLASSIFICATION OF INDICATORS FOR COMPLEX ASSESSMENT OF AGRICULTURAL MACHINERY

      pg(s) 221-224

      The efficiency of the machines depends on the completeness of the scope of the indicators and the factors with which they are linked.

      In choosing the best solutions, it is necessary to evaluate the system metrics, and the optimal option machine or set of machines to be chosen using optimization criteria.

      The indicators for the quality assessment of mechanized works should be divided into common types for all mechanized works and for separate groups of technological processes: soil treatment, sowing and planting, plant care, harvesting of crops.

      The system of indicators for the evaluation of agricultural machinery is expressed and evaluated with a large number of properties, indicators and characteristics of quality and reliability.

      In general, quality has four groups of properties: feasibility, social, bio-ecological and reliability.

    • TESTING OF ULTRASONIC SENSOR FOR MEASUREMENT OF WASTE VEGETAI ON MASS

      pg(s) 225-227

      The object of the study is an ultrasonic sensor type UT2F/E7-OEUL which measures the presence of a body in the range of 350 to 6000 mm. The sensor was mounted in a suitable place in the combine harvester. Experiments were conducted on three types of waste vegetation mass (WVM): wheat, beans and alfalfa in field and laboratory conditions. A database of sensor measurements was obtained. A single-factor dispersion analysis task was formulated. The results obtained using relevant specialized software showed that the sensor is operational regardless of the type of WVM.

    • MECHANISED TECHNOLOGY FOR GROWING AND HARVESTING CORN

      pg(s) 228-231

      Improvement of applied modern mechanized technologies for growing and harvesting of corn, introduction of hybrids with a low and strong stem, suitable for thicker sowing, irrigation, etc. Lead to an increase in average grain yield per hectare.

      The best precursors for corn are bean cultures, peas, alfalfa etc. Keeping this crop rotation turns out to be appropriate for successful weed control. Permanent cultivation of corn is also perceived, but it should not last for more than three consecutive years on the same area. In addition, corn is also eligible for cultivation in the case of reduced soil cultivation, incl. And through direct sowing. Obviously, with these extensive opportunities for crop rotation, account should be taken of the period of natural soil compaction and of the type of soil. Production and protection is carried out by two technologies: harvesting of cobs and harvesting of grain.

      The main advantages of the first technology are the following: harvesting can be done at higher grain humidity (about 30%) when the stems are still green and can be ensiled; No additional energy costs are required to dry the grain; Timely release of sowing areas for subsequent crops.

      When grain maize is harvested, the development of the maturity phase and the decrease of grain moisture should be observed, as the maturity increases considerably in the harvest losses. With the prolongation of the maize harvest, the biological losses are particularly high mainly due to fallen cobs, which reach up to 25%.

      With the maturity phase of corn growing, the productivity of combine harvesters’ increases, but taking into account the increase in losses, the optimal harvesting time for corn should be done on an economic basis.

    • DYNAMIC COMPUTER MODELING OF ARABLE WALKING TRACTOR WITH PLOW

      pg(s) 232-235

      The subject of the study is a motocultivator whose construction is designed for soil cultivation on small-scale private farms. Magnitudes – variables and constants that characterize the statics and dynamics of the motocultivator are identified. The motion equations are derived based on the corresponding body simplifications that move in the vertical-longitudinal plane with two degrees of freedom. The computerized simulation model of the dynamic system was developed using the Vemsim software. The numerical solution has been obtained. After analysis the relevant conclusions are made to improve the sustainability of the motocultivator movement within the required controllability.

    • OPTIMIZATION OF THE NUMBER OF HARVESTING AND TRANSPORT

      pg(s) 236-238

      The efficient operation of the harvesting transport complex (grain harvester – transport aggregate) depends on the organization of the transport service and the identification of the necessary means of transport is a probable task.

      An economically viable ratio counts combines, service vehicles for which minimizes the target function:

      Overview of pre-selection – transport complex as a mass service system.

      When machines are operating in a group, service requests are continually being carried out on a grain harrow filled grain hopper and after unloading the hopper, the combine is restarted and is a potential source of new orders.

      Thus, the "harvester-car" system is considered a mass service system in which a service request per unit time arises on average. We assume that the stream of queries is a simple (Poisson) stream that is ordinarily, stationary, and without consequences.

      The proposed model is certified with real data for agricultural cooperative in Yambol and the results show that for 5 CLAAS combine harvesters, is optimally served by three cars working in a group.

    • DETERMINATION OF THE LIQUIDITY VALUE OF AGRICULTURAL AND FORESTRY EQUIPMENT

      pg(s) 239-241

      The structure of production in agriculture is changing with the change of priorities, both at EU and national level. On the one hand, this is due to interconnection in individual sub-branches, on the other, to the replacement of traditional technologies with new ones. In both cases, this requires the maintenance of more equipment than is necessary for production and the corresponding increase in the cost of production and the reduction of the profit from production. Significant lagging of the machine-tractor fleet renewal processes and increased loading of the used equipment imply intensive physical wear and obsolescence.

      Depending on the reasons for write-off, when determining the liquidation value of the machinery, account shall be taken of special features and the possibilities for further use of individual elements (parts, assemblies and aggregates). Several approaches are used to determine the liquidation value:

      – the whole machine is considered scrap. The approach is applicable to working machines and attachments to self-propelled agricultural machinery;

      – the whole machine is classified as scrap but is dismantled and divided according to the type of scrap (ferrous and non-ferrous metals). The approach is applicable to retractors and attachments to self-propelled agricultural machinery as well as stationary machinery for primary production processing;

      – the machine is rated as scrap of ferrous and non-ferrous metals and second-hand spare parts. The approach is only applicable to physically worn machines.

      In addition to that, an improved methodology for assessing the liquidation value of different groups of agricultural machinery for moral and physical extinction with and without residual resource elements is suggested.

    • OPTIMIZATION OF LINKED PROCESSES ON EXAMPLE OF WHEAT AND MAIZE HARVESTING

      pg(s) 245-249

      The subject of the paper are linked processes in agriculture. Sophisticated relations between operational and transportation farm practises in time, place, and mass balance need compound simulation based on computer software. Important prerequisites for a good solution is a well-founded land management project. The last one have to include at least proper crop rotation plan and corresponding road net. The different combinations of crop yield, bulk density, distant of transportation for distinct plants require many concrete solutions. Furthermore, transportation can be realized with or without intermediate capacity like buffers, bins, overloader trailers, exchangeable trailers, etc. For fastets harvest, computation are made with maximum number of selfpropeler harvesters or enough to end of crop gather in acceptable periods. In the example, a joint work of Claas Lexion 600 and tractor with 9, 12 and/or 21 tons carrying capacity of trailer are discussed. For easy choice of every concrete solution, additiobnal information can be used like linked processes performans and graphic illustration. The proposed optimal procedure garatees enough data for reasonable solution based on real combinations of technology, machinery, vehicles, intermediate and final capacities.

  • CONSERVING OF THE RESOURCES

    • A METHODOLOGICAL APPROACH TO THE STUDY OF THE PLANT AND LIVESTOCK RESIDUES COMPOSTING PROCESS

      pg(s) 253-255

      A methodology of the study of the process of composting plant and livestock breeding residues has been proposed. Wheat straw and poultry manure are used to study the composting process. The main factors that are most relevant to the composting process are the following: compost humidity, the carbon-nitrogen ratio and the straw-cutting size. A chemical analysis of the straw and poultry manure was determined before and after the experiments.

    • MONITORING OF WEEDS IN CROPS OF LEGUMES AND CEREALS GROWN UNDER CONDITIONS OF ORGANIC FARMING

      pg(s) 256-260

      During the period 2011 – 2013 a field experiment was conducted at the experimental field of IASS “Obraztsov chiflik” – Ruse, with ecologically grounded crop rotation, including the cultivation of two legumes /field beans, peas/ and two cereals /wheat, malting barley/ on an area after conversion. The experiment started after the eightfold scheme of Georges Ville in 3 replications, situated after Ryumker, the size of the harvesting plot being 52,5m2. Pesticides were not applied on the crops, also and synthetic fertilizers and improversof soil, prohibited for the organic production.

      The objective of the study was to observe and describe the biological regulation of weeds in legumes and cereals, grown under conditions of organic farming.

      In the organic field, the diversity of weed species was influenced by climatic conditions, soil tillage and crops. There were differences in weed infestation of crops only in terms of quantity of weeds per m2. In that case the differences in weed infestation were in direct relationship with certain biological characteristics of the crops. The species Matricaria chamomilla (L.), Anthemis arvensis (L), Capsella bursa-pastoris (L.), Setaria viridis (L.), Echinochloa crusgalli (L.), Digitaria sanguinale (L.), Lamium purpureum (L.), Convolvulus arvensis (L.) и Cirsium arvense(L.) were reported over the whole three-year period.