ФОРМАЛЬНІ ОПИСИ СКЛАДНИХ ДИНАМІЧНИХ СИСТЕМ І СПЕЦИФІКАЦІЇ СИМУЛЯТОРІВ, ПОБУДОВАНИХ ЗАСОБАМИ МОВ МОДЕЛЮВАННЯ

Abstract

The concept of developing parallel modeling languages (PML) of complex dynamic systems (CDS) based on the analogy between the principles of operation of serial languages (SL) and MIMD parallelism provides for the purpose of "Functional element of the SL block diagram - MIMD process", which transforms the SL specifications of serial simulators (block diagrams) in the structure of virtual parallel simulators. Virtuality is due to the atypical for MIMD-systems "fine granulation" of the processes generated by this purpose and the connections between the processes, which must be appropriate to the connection schemes of the functional elements of SL simulators. The architecturally relevant implementation of a parallel simulator of any CDS is related to the form of its mathematical description and the corresponding Simulation model. CDS with concentrated parameters are described by systems of ordinary differential equations (ODE) of the first order, systems of equations of different orders, systems of differential-algebraic equations (DAE-Problem), and in network CDS there are sums of derivatives from different variables. CDS with distributed parameters are described by systems of differential equations in partial derivatives, so the development of Simulation-models is associated with the approximation of equations by spatial coordinates and the formation of ODE systems. For these forms of description Simulation-models and corresponding SL-specifications in the form of block diagrams of SL-elements are considered, which is the basis for construction of virtual MIMD-simulators of two possible levels of granulation of processes: the basic level " SL-element - process" provides MIMD-processes "Shallow granulation", in which there is uneven loading of processes and an unfavorable relationship between the volume of computational operations and data exchange operations between processes; The level "Group of SL-elements - process" corresponds to the stage of simulator development, in which the specifications use the composition of SL-elements according to a certain principle, for example, "One equation Simulation model - Group of SLelements to solve the equation - Coarse granulation process"