Leptospirosis is a zoonotic disease that is caused by the pathogen Leptospira, and it can spread indirectly or directly from infected animals to humans. According to the official statistics from the Malaysian Ministry of Health, leptospirosis outbreaks appeared to be in the most critical condition in the recent few years. The Susceptible--Infected--Recovered compartmental model and its extensions have been applied widely in disease modeling. This paper aims to present a compartmental model for leptospirosis spread in Malaysia. Using this approach, an epidemiological model is formulated
The article analyzes scientific publications, which showed that for most part of the study transients processes in the long power lines with distributed parameters is carried out by equivalent to the known equation of a long line with distributed parameters by a circular equivalent, or solve this equation using simplified approaches. These approaches require deterministic boundary conditions to the long line equation, which is not always possible when modeling transients processes in electrical networks.
One of the key problems in the implementation of closed-loop control systems is to measure all states of a dynamic system, especially, when there are severe environmental conditions. Consequently, the use of certain types of sensors is impossible for technical or economic reasons. Also, in electromechanical systems, there are a lot of values that cannot be directly measured by physical sensors. Thus, mathematical algorithms named as observers and estimators are in use to calculate the states of the dynamic system utilizing math model and available set of sensors.
The article analyzes scientific publications, who showed that for the most part, the study of switching transients in electrical networks during automatic reclosing cycles of circuit breaker, are carried out without taking into account the influence of electromechanical processes in the mechanisms of circuit breaker contacts, despite the fact that the speed of their course is commensurate with the speed of the electromagnetic processes.
The mathematical model of an electromechanical system with an asynchronous generator with rotor’s current regulation by frequency converter with an autonomous voltage inverter controlled by current controllers has been described in the article.
Mathematical modeling of 2-hydroxyethylmethacrylate with polyvinylpyrrolidone copolymerization process according to technological parameters of the exothermic reaction has been carried out by Scheffe’s simplex-lattice planning method. Optimization of polymer monomer composition formula has been carried out and the regression equations of the main parameters of exothermic polymerization –– gelation time, the duration of the gel effect area, and the maximum temperature of the exotherm have been obtained. Using the mathematical model obtained, the content of the initial composition has been
On the basis of a generalized interdisciplinary (interdisciplinary) method of mathema- tical modeling, which is based on modifications of the integral variational principle of Ha- milton-Ostrogradsky, proposed mathematical model of the ultra-high voltage circuit-breaker the main emphasis of which is placed on modeling work the mechanism of moving his contacts.
The paper on the basis of interdisciplinary approaches presented mathematical model of the electric power system, a key element of which is the power line that connected substation “Zakhidnoukrayins’ka” — substation “Vinnyts’ka”. On this basis, the analysis of transients in the power line to single-line performance. Results transients are presented as figures which analyzed.
The article presents an analysis of automatic adjustment system of level liquid in the tank in case the use of frequency-controlled asynchronous electric pump unit. It is proved expediency and conditions of use P- and PI- regulator. The recommendations of settings regulators have given. These results of automatic adjustment control system of level are obtained by computer simulation using Matlab-Simulink.
The electromechanical and electromagnetic transient processes in a power generation system with turbo-generator and brushless excitation for main working regimes are analyzed in the article. An analysis has been carried out by means of developed with the use of the object-oriented method the mathematical and computer models that take into account non- linearity of synchronous machines and discreteness of semiconductor converters.