Eugene Kindler

Component-based simulation for a reconfiguration study of transitic systems

This paper is organized as follows. Part A presents the context of reconfiguring transitic systems and the main idea in implementing the decision step. It comprises sections 1 to 3. Section 3 presents an example that illustrates the concepts presented in the next sections. Parts B and C express the models and principles used to simulate transitic systems, the result of which will be helpful for choosing the new configuration. Part B focuses mainly on models. It comprises sections 4 to 6. Part C focuses mainly on simulation principles. It comprises sections 7 to 10.

Conveyors With Rollers as Anticipatory Systems: Their Simulation Models

The conveyors with rollers are good examples for man‐made anticipatory systems in the weak sense, as they represent rather complex systems. The control of them has to anticipate into their future. Nowadays the control is performed by computers and an idea arises to implement the model serving for the anticipation as a simulation model running at the controlling computer. The quality of the design is tested by simulation, too, and therefore the design‐oriented simulation of the conveyors has to include their controlling and simulating computers. In other hand, the design‐oriented simulation has to reflect the operating‐oriented simulation. Some running models have been implemented using SIMULA and are presented.

Computer models of systems containing simulating elements

The paper is oriented to simulation of systems that contain simulating elements, to the use of such simulation and to its implementing. Obstacles are presented and methods to overcome them as well. Of a good use, programming languages that are simultaneously object-oriented, agent-oriented and block-oriented appear, namely the first object-oriented language that was ever designed and implemented, i.e. SIMULA. An example is presented, concerning computing short paths in dynamically changing networks (namely container yards). This example was implemented and runs at computers.

Object‐Oriented Representations of Formal Theories as Tools for Simulation of Anticipatory Systems

The paper is oriented to application of locally used formal theories as tools for analysis and modeling of anticipatory systems, and especially of nesting anticipation, which takes place e.g. in anticipation during a design of a system that is expected to be anticipatory one. The specialization of theories enables to “tailor” them near to the studied systems and the nesting of theories enables formulating exact theories of systems, the elements of which carry their proper theories. In certain programming languages such theories make easy computer model construction and especially automatic generation of simulation models.

SYSTEMS OF MATERIAL FLOW

Abstract The systems of material flow are discrete event dynamic systems reflecting transport or material in various structures of places. They are composed of places (sources and sinks) joined by branches, along which transport means move; those means are loaded in the sources and unloaded in the sinks, generally with an assistance of load en and unloaders normally located in the places. The entire class or the problems was discovered in agriculture, where one specialist often meets a large spectrum of systems or material flow within a short time interval of its professional activity. It happens when he studies various agricultural enterprises from the same point of view or when he studies one enterprise from various agricultural points of view.

A FORMALIZATION OF SOME SIMULATION LANGUAGE CONCEPTS

A formalization of some simulation modeling concepts is described, which is used as a conceptual framework among simulationists and in the educational process. The notion of dynamic system is hierarchically constructed from attributes and classes: the domains of the classes are formed by elements with “similar” attributes and a set of classes is a system if it satisfies certain axioms. A simulation model is composed of two systems and four mappings also satisfying axioms. This conception reflects the capability of simulation languages to not only describe the dynamics of systems but also their structure. The theory is a framework for any sort of simulation models (discrete, continuous, combined, hybrid, analogue, galvanical, aerodynamical etc.) and allows a classification of the set of all simulation languages according to their semantics.

Special Session: Simulation in Production and Logistics

Abstract Since a long time, simulation has been a general technique to study and research production and logistic systems. Nowadays a synthesis of simulation with other computing methods is often made so that that computing is represented by a computer model. That model can be a simulation one or not. Thus nesting models penetrate into simulation.

Universal transport processes

Abstract The paper concentrates to so called material flow systems, i.e. queuing systems oriented for transport of “material”, which can be substance, energy, information etc. The characteristics of the material flow systems is presented and the principles of their simulation by means of SIMULA are described. Though the material flow systems have been discovered in agriculture, they have rich interpretations in industry, transport and in information processing networks. SIMULA offers an especially suitable insight into the whole class of those systems.

Combined simulation languages: some results from Eastern Europe: Dear Editors

The language NEDIS (acronym for Nepreryvno-diskretnyje sistemi = continuous/discrete systems) has been implemented in Kiev (see Reference 1). It uses the Simula 67 class concept together with commonly known facilities for discrete simulation (similar to, e.g., SOL). It has no subclasses and resume-statements as in Simula 67. But it allows joining instances of blocks representing continuous functions, as they are known in CSSL, CSMP III, etc. Their outputs can vary continuously during simulated time. I do not know