The Second International Conference “Problems of Cybernetics and Informatics” September 10-12, 2008, Baku, Azerbaijan. Section #5 “Control and Optimization” www.pci2008.science.az/5/15.pdf ALGORITHM FOR DEFINITION OF QUANTITY OF FERTILIZERS FOR ACHIEVEMENT OF NECESSARY RATIO OF NUTRITIOUS ELEMENTS Elkhan Sabziev 1 , Adalat Pashayev 2 , Vagif Guliyev 3 , Atamali Mammadov 4 1 Cybernetics Institute of ANAS, Baku, Azerbaijan, elkhan@kiber.az 2 Kiber Ltd Company, Baku, Azerbaijan, adalat@kiber.az 3 Institute of Soil Science and Agrochemistry of ANAS, Baku, Azerbaijan, info@kiber.az 4 Cybernetics Institute of ANAS, Baku, Azerbaijan, info@kiber.az Introduction. One of main tasks of optimization of nutrition of hothouse plants is use the standard, on phases of development of plants, solutions with the appropriate balanced parities of macro- and microelements. The allowable marginal levels of elements in the water for preparation of nutrition solutions should be in limits established by long-term laboratory and field experiments. They are given as standard units for each nutritious element, or as shares of percents. Besides the allowable limiting deviations as percentage parameters are given too. One of industrial ways of cultivation of plants is hydroponics, meaning “job with water” [1]. This method has wide application in hothouses and actually exempts from additional jobs on study of structure of soil and further updating of structure of fertilizers depending on it. Certainly, in each hothouse facility used spray water has the certain chemical structure and parameter pH, which it is necessary to take into account at definition of required quantity of nutritious elements for maintenance high (best) productivity. However, within the framework of this job, we shall consider, that required quantity of nutritious elements already are determined in view of these parameters. It is necessary to notice, that the agriculturists first of all supervise such basic nutritious elements, as nitrogen (NO 3 – and NH 4 +),, phosphorus (P 2 O 5 ), potassium (K 2 O), magnesium (Mg 2+ ), calcium (Ca 2+ ), sulfur (SO 4 2- ) etc. Then pay attention to a parity of microelements: Zn, Mn, Co, Se, Cu etc. Thus, the quantitative portion of nutritious elements necessary for achievement of a desirable crop, for each cultivate plant is considered as known. However, whereas the biological systems are flexible, the optimum parities of nutritious elements can be carried out with the some approximately. On the other hand, quantities of available nutritious elements in structure of fertilizers also are known. Now, in order to the farmer in the hothouse facilities applied method hydroponics, it is necessary to determine quantity of each accessible fertilizer for reception of required nutritious structure. Thus, it is desirable that most favorable was chosen from numerous variants of the decision with the economic point of view. Mathematical formulation of the problem. Let's assume that it is required to receive structure consisting of M nutritious element, nitrogen, phosphorus, potassium, magnesium, calcium, sulfur etc., accordingly in the ratio M C C C C ~ : : ~ : ~ : ~ 2 1 0 L , where 1 , , 1 , 0 , 0 ~ − = ≥ M j C j K . For each j the equality 0 ~ = j C means that in the given structure is no nutrition element with the same index. 54