Įprasti elektromechaninių vykdymo sistemų dinamikos optimizavimo metodai – kiekybinis ir simetrinis optimumai turi savų privalumų bei trūkumų ir yra pagrįsti pastovios struktūros greičio reguliatoriais: proporciniu (P) ir proporciniu integruojančiu (PI). Siekiant suderinti kiekybinio ir simetrinio optimumų tiekiamus privalumus bei pašalinti jų trūkumus, užtikrindamas elektromechaninės vykdymo sistemos greičio dinaminį nuokrypį neviršijantį 5 % ir nulinį greičio statinį nuokrypį ištirtas P-PI valdymo dėsnio kintamos struktūros reguliatorius. Remiantis ITAE integraliniu kokybės rodikliu nustatyta geriausią elektromechaninės vykdymo sistemos dinamikos kokybę užtikrinanti greičio reguliatoriaus valdymo dėsnio perjungimo parametro priklausomybė nuo statinės apkrovos. Atlikti elektros pavaros su kintamos struktūros greičio reguliatoriumi veikimo imitacijos tyrimai MATLAB/Simulink programa. Nustatyta, kad P-PI kintamos struktūros reguliatorius užtikrina nuo 60,7 % iki 83,15 % geresnę elektromechaninės vykdymo sistemos dinamikos kokybę nei pastovios struktūros simetrinio optimumo reguliatorius (PI). Tačiau naudojant P-PI kintamos struktūros reguliatorių gaunama nuo 2,76 % iki 13,67 % blogesnė sistemos dinamikos kokybė nei PI-P-PI kintamos struktūros reguliatoriaus atveju. / Classical dynamics optimization methods of the electromechanical servo drives are the quantitative and symmetrical optimums. These methods have advantages and disadvantages and are based on the fixed structure velocity controllers – proportional (P) and proportional-integrating (PI). In order to coordinate the advantages and eliminate disadvantages of the quantitative and symmetrical optimum methods have been investigated the P-PI variable structure velocity controller in the electromechanical servo drive. The P-PI variable structure velocity controller ensures that the dynamic error does not exceed 5 % and enables avoiding the static velocity error. According to the ITAE (Integral of Time multiplied by Absolute Error) quality indicator it was determined the control law switching parameter dependence on the static load ensuring the best dynamical quality of the electromechanical servo system. The investigations have been accomplished simulating the electromechanical servo system with P-PI variable structure velocity controller using MATLAB/Simulink program. It has been determined that P-PI variable structure velocity controller ensures from 60,7 % to 83,15 % better dynamical quality of the electromechanical servo system compared to the fixed structure controller (PI) of the symmetrical optimum. But using P-PI variable structure velocity controller the dynamical quality declines from 2,76 % to 13,67 % compared to the PI-P-PI variable structure velocity controller.

The subject of the research is production costs classification used in the Lithuanian manufacture enterprises and farmers’ farms. The goal of the work is to reason the expedience of selection of the classification features in practice and to measure the adaptation opportunities of the selected classification features in the Lithuanian enterprises and farmers’ farms, after the costs classification potential have been analysed. The tasks are as follows: 1) to analyse the principle of production costs and classification potential, and to reason the expedience of selection of the classification features; 2) to analyse individual types of costs according to the selected classification features; 3) to check and measure the adaptation opportunities thereof in practice. The research methods include the logical analysis of economic literature containing comparison and summarizing of theoretical statements. The practical experience of costs classification gained in the Lithuanian manufacture enterprises and agricultural partnerships has been analysed using the method of analysis and synthesis. The results of the research have been described using the methods of comparison and summarizing the outcome, as well as the monographic method of analysis. After having analysed the principle of costs and classification potential thereof with regard to the objectives set in the area of cost accounting, the selected costs classification features are introduced in the work, which are essential in... [to full text]