• CONSERVING OF THE RESOURCES

    Water productivity and the effect of watering on apples grown under conditions of optimal irrigation and water deficit

    Mechanization in agriculture & Conserving of the resources, Vol. 66 (2020), Issue 4, pg(s) 150-153

    In order to determine the productivity and the effect of irrigation on apples grown under soil and meteorological conditions in the area of the village of Chelopechene – Sofia, research was conducted on drip irrigation of a plantation of the “Florina” variety, and different regimes were tested – from complete satisfaction of the daily needs of water to irrigate the culture with irrigation rates reduced by 20% and 40%. A non-irrigation variant has also been tested.
    The productivity of the irrigation rate at optimal irrigation varies by years from 16.3 to 28.0 kg.ha-1.mm-1, and at 40% reduction of the irrigation rate from 19.3 to 26.0 kg.ha-1. mm-1
    The highest values of productivity of the irrigation rate are reached at irrigation with a 40% reduction of the irrigation rate, in the dry 2004 high values were obtained and at the variant irrigated with 100% irrigation rate 28,0 kg.ha-1.mm-1
    The optimization of moisture in the active soil layer contributes to a significant increase and stabilization of yields, which for the test conditions are from 1266 to 2087 kg / dka. Additional yields ranged from 542 to 821 kg / dka, averaging over the study period.

  • CONSERVING OF THE RESOURCES

    Water productivity and the effect of watering on apples grown under conditions of optimal irrigation and water deficit

    Mechanization in agriculture & Conserving of the resources, Vol. 66 (2020), Issue 2, pg(s) 81-85

    In order to determine the productivity and the effect of irrigation on apples grown under soil and meteorological conditions in the area of the village of Chelopechene – Sofia, research was conducted on drip irrigation of a plantation of the “Florina” variety, and different regimes were tested – from complete satisfaction of the daily needs of water to irrigate the culture with irrigation rates reduced by 20% and 40%. A non-irrigation variant has also been tested.
    The productivity of the irrigation rate at optimal irrigation varies by years from 16.3 to 28.0 kg.ha-1.mm-1, and at 40% reduction of the irrigation rate from 19.3 to 26.0 kg.ha-1. mm-1
    The highest values of productivity of the irrigation rate are reached at irrigation with a 40% reduction of the irrigation rate, in the dry 2004 high values were obtained and at the variant irrigated with 100% irrigation rate 28,0 kg.ha-1.mm-1
    The optimization of moisture in the active soil layer contributes to a significant increase and stabilization of yields, which for the test conditions are from 1266 to 2087 kg / dka. Additional yields ranged from 542 to 821 kg / dka, averaging over the study period.

  • TECHNOLOGIES

    ALGORITHMS FOR VECTORIZING DRAWINGS OF THE UPPERS SHOES

    Machines. Technologies. Materials., Vol. 12 (2018), Issue 3, pg(s) 121-123

    Perfection of methods of footwear production technology through the use of computer-aided design systems allows to develop production technology, to supply consumers with high-quality and comfortable footwear. At the stage of development of design and design documentation for a new model of footwear, there are a number of difficulties, the formalization of which using computer graphics tools would significantly reduce the subjectivity of the designer’s design decisions or free it from performing the same procedures. In the framework of the research known algorithms for vectorizing the drawing were considered, on the basis of which a new method using a set of apertures appropriate for the drawings of the upper parts of the shoe was proposed.

    The results of the research were – formulated requirements for the "Digitization" module; its structural and logical scheme, allowing automated input of information about drawings of designs of the uppers shoes in CAD; structural and logical scheme of a topological algorithm that allows vectorizing drawings of the uppers shoe in accordance with the set of apertures.

    The calculation of material costs for the design of footwear was also carried out, which showed the economic efficiency from the introduction of the proposed method into production.

  • TECHNOLOGIES

    IMPROVING THE RELIABILITY OF AGRICULTURAL MACHINERY, USING THE METHOD OF RESTORATION OF PARTS UNDER SUBMERGED ARC WELDING, AND ITS TECHNICAL AND ECONOMIC EVALUATION

    Machines. Technologies. Materials., Vol. 11 (2017), Issue 6, pg(s) 307-310

    The basic features of calculating the reliability of agricultural machinery are shown, in contrast to industries such as mechanical engineering, radio and television equipment, automation systems and etc., in which machines and apparatus operate in steady modes, while agricultural machines do in difficult soil and climatic and dynamic conditions.

    Еconomic aspect of reliability is substantiated and patterns of change in the efficiency of use of agricultural machinery in time are established, the economic parameters of reliability are determined. With the help of the theory of similarity and dimensions as well as the planning of multifactor experiments, through the original installation manufactured by us, the basic physical and mechanical properties of metal coatings are studied, obtained by welding under flux, there are relevant similarity criteria determined that characterize the process of restoration of worn parts and, after processing of experimental data an analytical view of criterion equation is formed and rational modes of the restoration of parts under submerged arc welding are set. Further, to optimize the process, the scheduling theory of extreme experiments has been used and as factors in the regression equation there have been chosen most significant similarity criteria. In methodics elaborated by us, it was obtained an adequate equation and by a method of steep ascent (movement along the gradient), there were determined optimal modes of recovery for metal coatings with high physical and mechanical properties (hardness, wear resistance).

    Under these regimes there were recovered worn ploughshares and their operational check showed an increase of resource as many as 1.4…1.5 times. For surfacing worn parts with complex configurations (ploughshare plows, cultivators paws), we have manufactured a special copier allowing to recover the items automatically, in a continuous mode. The feasibility study of the developed resource-saving innovative technology has shown that the restoration of 800 ploughshares provides an yearly economic effect of EURO 1,462.