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IV.5. I. Krivy, E. Kindler, Education and Training in Computer ... - Ecet

International Conference on **Computer** Systems **and** Technologies – CompSysTech‘2004_____**Education** **and** **Tra ining**

International Conference on **Computer** Systems **and** Technologies – CompSysTech‘2004_____analysis of the model. Such analysis arises almost automatically **in** parallel with theprocess of the stepwise formulation of the model **in** SIMULA **and** with its stepwiseref**in****in**g. Some of graduate students cont**in**ue **in** construct**in**g **and** apply**in**g simulationmodels (especially nested ones) dur**in**g their doctoral studies.QUALIFICATION FOR IMPLEMENTING NESTED SIMULATION MODELSAs one can see, at the beg**in**n**in**g phase the students were not forced to implementmodels applicable **in** nested simulation. Nevertheless, they were led to simulate rathercomplex hard systems such as:• crop works **in** greater farms: systems composed of comb**in**ed harvesters, storages **and**trucks that transport the harvest from the harvesters to the storages,• sow**in**g works **in** greater farms: systems composed of storages, sow**in**g mach**in**es **and**trucks that transport the seed corn from the storages to the sow**in**g mach**in**es,• age**in**g of mach**in**es used **in** greater farms: generation of data support**in**g the decisionmak**in**g whether a mach**in**e should be seen as repairable or replaced by a new one,• vertical matrix storage served by a conveyor: generat**in**g various control algorithmsgovern**in**g the conveyor **and** their test**in**g relat**in**g to the possible flow of requirements,• pork meat production: systems of halls where pigs of different age are breeded **and**where a cycle of mak**in**g sows **in**-pig – pigg**in**g exist, possibly with decisions what sowis to be replaced by a new one; the halls are served by human workers who respect acerta**in** week-based operat**in**g rhythm,• veter**in**ary sanitation **in** regions: systems of sources of biological waste(slaughterhouses etc.), a center for process**in**g the waste **and** trucks transport**in**g thewaste from the sources to the center with respect to governmental laws concern**in**g thehygiene,• models of governmental production made by **in**teract**in**g regions.Some models were stepwise prepared by us (i.e. by the authors of this paper)**and** used as demonstration ones **in**form**in**g the students on the large spectrum ofsimulation:• mach**in**e production: various systems reflect**in**g occasional dem**and**s com**in**g fromCzech enterprises,• wash**in**g of contam**in**ated textiles **in** nuclear power stations,• transport of radioactive waste from nuclear power plants to subterranean disposal site:test**in**g of various algorithms for configuration of transport frames carry**in**g conta**in**ers,• solidification of radioactive waste: test**in**g of various methods of the solidification withrespect to accidents **and** to irradiation of the human staff,• local epidemics,• dissem**in**ation of **in**sect pests **in** forest,• forest fires,• potassium ion dynamics **in** the environment of neural cells,• use of beds by patients **in** hospitals,• iod**in**e transport **in** human organisms,• airplane w**in**g assembly: optimization of the order of assembly steps,• fault systems of large parts of nuclear power stations.- IV.5-2 -

International Conference on **Computer** Systems **and** Technologies – CompSysTech‘2004_____All the models mentioned above were applied **in** enterprises outside the universities.Beside them, we also prepared some demonstration non-simulation methods:• two-dimensional Cartesian geometry – concepts of po**in**t, circle, **in**cise, rectangle, etc.;relations „a po**in**t is **in**side (or at the boundary of) a circle (rectangle, …)“ etc.,• vector **and** matrix algebra – concepts of n-dimensional (numerical) vector **and** matrixtogether with their operations,• complex number arithmetic,• foundations of chess play – concepts of component of the chessboard, chessman, itsspecialization to particular sorts of chessmen, pane, etc.,• geometry of freely placed objects – concepts of circle, rectangle, cyl**in**der, cone,rectangular parallelepiped, etc., three-dimensional concepts be**in**g declared asspecializations of two-dimensional ones.Beside these models, we implemented also so called fictitious simulation ones, i.e.models of fictitious systems, which serve to fast implementation or modification of complexnon-simulation algorithms:• configuration of chess-queens,• sheep-wolf play,• escape from a maze,• shortest path **in** a transport network,• quasi-parallel process**in**g of several files **in**to one file, depend**in**g on special propertiesof the data occurr**in**g **in** the files,• process**in**g of arithmetic **and** logical expressions **in**to systems of comput**in**g **and****in**teract**in**g blocks,• synthesis of free rhythm structures: experiments with generat**in**g first millenniumEuropean melodies accord**in**g to certa**in** hypotheses on their rhythm.The fictitious systems are supposed to produce the same data as the **in**tendedalgorithms.OVERVIEW OF IMPLEMENTED NESTED SIMULATION MODELSIn the n**in**eties students were acqua**in**ted with certa**in** cases of nested simulation, upto this time only **in** a passive mode (they were not forced to engage **in** implement**in**g suchmodels). The pr**in**ciple was as follows: us**in**g a simulation model of a realistic system,fictitious simulation was applied, i.e. a model applied **in** a fictitious simulation was **in**cluded**in**to a model of a realistic system. The examples of such nested simulation models are asfollows:• simulation of a mach**in**e production system that applies **in**duction carriages foroperation transport (the fictitious simulation was used for the shortest path comput**in**g),• simulation of **in**terregional product exchange **in** Czech republic (the fictitious simulationwas used for **in**sert**in**g geometrical figures to the tables of the simulated results),• conta**in**er term**in**al with ground-mov**in**g operational transport tools (e.g. forklifts) thatmove at the places free of conta**in**ers (the fictitious simulation was used for the shortestpath comput**in**g).All three studies mentioned above were made for **in**stitutions belong**in**g to other fieldsthan education. The last of them was implemented under the project COPERNICUS-312AMCAI managed under European Commission **and** coord**in**ated by Center of FraunhoferInstitutes **in** Munich (Germany).- IV.5-3 -

International Conference on **Computer** Systems **and** Technologies – CompSysTech‘2004_____S**in**ce 1998 students were acqua**in**ted with reflective simulation, namely with thefollow**in**g models:• queu**in**g system (a bank) with one or more dispatchers who decide on the number ofemployees serv**in**g the customers at the tellers [4]: when a dispatcher decides tochange the number he simulates what could happen **in** the near future **in** order to testwhether his decision is not wrong;• conta**in**er term**in**al with ground-mov**in**g operational transport tools [1,5]: the nestedsimulation was used for test**in**g whether the computed shortest path will not lead to aconflict with an object that was not place at its place when the path was computed butwas transferred there dur**in**g the **in**itial phase of the mov**in**g accord**in**g to the computedpath. Also this model was applied under the project COPERNICUS DAMAC-HP;• cyclical conveyor with free **and** motorized rollers [7]: simulation solution of variousproblems concern**in**g its behavior after faults **and** **in** case of too high frequency ofdem**and**s; the implementation was made for a French enterprise;• simulation of urban traffic **in** the town Havířov [2]: the human plann**in**g made by thepassengers **and** us**in**g their imag**in****in**g of the future mov**in**g along bus traces **and** theirpotential sequenc**in**g was modeled by simulation.CONCLUSIONS AND FUTURE WORKS**in**ce the end of the fifties, simulation has been a very efficient technique for appliedcomputer science, stimulat**in**g both mathematical model**in**g **and** programm**in**g paradigms.S**in**ce the fifties, simulation has passed trough a rich development, the most importantresult of which is the reflective simulation, i.e. simulation of systems that apply simulationdur**in**g their existence **in** order to anticipate their possible future states. Construct**in**gsimulation models for reflective simulation is far from the everyday simulation rout**in**e. Theauthors received **in**terest**in**g experiences **in** teach**in**g simulation, so that nowadays certa**in**university (undergraduate) students are able to construct **and** use reflective simulationmodels. The students were stimulated to use the object-oriented programm**in**g techniquefor construct**in**g simulation models of more **and** more complex systems, so that **in** the lastyears the **in**terested students were able to use sophisticated object-oriented programm**in**gtools (namely SIMULA) for implement**in**g reflective simulation.The next progress of reflective simulation is ensured by two aspects. The first one isa larger reflection of the reflective simulation **in** the students sem**in**ary works **and** theses,the second one consists **in** the automation of certa**in** steps **in** construct**in**g reflectivesimulation models.Therefore, our future work will be oriented first to:• enlarg**in**g the spectrum of simulation applications from the **in**dustrial systems to otherones, namely to the system related more to life sciences (health care systems,ecological ones etc.),• design**in**g, implement**in**g **and** test**in**g a translator that converts conventional (nonreflective)simulation models **in**to those with reflective abilities.REFERENCES[1] Blümel, E. et al. Manag**in**g **and** Controll**in**g Grow**in**g Harbour Term**in**als. SanDiego, Erlangen, Ghent, Budapest: Society for **Computer** Simulation International 1997,308 p. (**K indler**, E. Chapter 4, Classes for object-oriented Simulation of Conta

International Conference on **Computer** Systems **and** Technologies – CompSysTech‘2004_____[3] **K indler**, E. SIMULA