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Petri nets is the well-known mathematical tool for the modeling and verification of parallel systems of all kind. Multiprocess Petri multinets with time stamps (MPTSM) are the newly introduced class of low-level Petri nets, whose definition and the properties are the main topic of this article; they generalize the properties of P/T Petri multiprocess multinets in the area of design, modeling and verification of generally parallel programming systems with the discrete time. The MPTSM with the support of the ASYNC-CALL operation can be then applied into the area of modeling and verification of multithreading programming systems based on the actor model of objectoriented programming, where all object are represented as independent computational entities with discrete time (i.e., active objects) that only respond to the received messages. This fact will be then demonstrated on the simple example of the programming system based on the client-server architecture that is operated in the distributed system environment where all the actors are synchronized in time with the unique central time source. [ABSTRACT FROM AUTHOR]

Petri nets is one of mathematical modeling languages for the description of all kind of parallel systems. The new class of P/T Petri multiprocess multinets (PPMM) and its ASYNC-CALL operation are introduced in this article and their base characteristic of the well-formed property is proved. PPMM then generalize the definitions of the birelational P/T Petri nets and the P/T Petri process nets and their operators that follows from the base ideas of Petri net processes and their property-preserving Petri net process algebras (PPPA). PPPA does not need to verify the composition of the Petri net processes because all their algebraic operators preserve the specified set of the properties. The PPMM with the support of the ASYNC-CALL operation can be easily applied into the area of design, simulation and verification of multithreading programming systems based on the actor model of object-oriented programming, where all object are modeled as independent computational entities (i.e., active objects) that only respond to the received messages. This fact is demonstrated on the simple example of the client-server programming system executed in the distributed environment. [ABSTRACT FROM AUTHOR]

One of the burning questions in majority of universities in the Czech Republic is maintaining and increasing the teaching process quality at permanently growing interest in university studies. Implementation of eLearning technologies indeed has been of a great assistance while addressing the stated issue however it is obvious, that conventional text study supports cannot fully substitute direct or mediated interactions of teaching staff with student. The complex rich-media visualization of the tutorial process becomes the absolute necessity for the overall transfer of information from the teacher to students. The issue of key aspects of implementing rich-media technologies at VŠB-Technical University of Ostrava in the Czech Republic is dealt with the MERLINGO Project (MEdia-rich Repository of LearnING Objects). Using rich-media technologies allows to carry out automated complete records of the whole educational process with minimum demands on financial, time, personnel and technological costs and to achieve their immediate access in the environment of LMS Moodle. Testing, evaluation or practicing students' knowledge especially in quantitative subjects such as mathematics or statistics can be also facilitated using LMS Moodle. The module Test, which is a standard part of commonly used e-learning environment LMS Moodle, is not very suitable for developing mathematical or statistical tests because it contains only a limited number of functions that can be used for creating quantitative tasks. At VŠB - TU Ostrava we have chosen the R language and Sweave and Exams libraries for generating quantitative tasks. Texts of tasks are created in the markup language LaTeX. Using the Exams library the tasks can be compiled and exported to PDF format or Moodle XML format. The eLearning methods described above entail a number of both technical and didactic problems and difficulties. The paper pointed out some of these problems and how the authors have dealt with them. The authors also present selected results of research among students who have already passed some eLearning courses containing these methods and tools. [ABSTRACT FROM AUTHOR]