Πλατφόρμες Προσομοίωσης

1. Τμήμα Μηχανολόγων και Αεροναυπηγών ΜηχανικώνΠανεπιστήμιο Πατρών Πλατφόρμες Προσομοίωσης ΜΑΡΙΟΣ ΠΑΤΡΙΚΟΥΣΑΚΗΣΑ.Μ. 453 ΧΑΡΑΛΑΜΠΙΑ ΠΥΛΑΡΙΝΟΥΑ.Μ. 435 Μεταπτυχιακό Μάθημα: «Τεχνολογίες Υποστήριξης Συνεργασίας» Διδάσκων: Νίκος Καρακαπιλίδης Πάτρα, Δεκέμβρης 2005

2. Simulation Software • Subject of discussion: The use and applications of simulation tools. • Purpose of the presentation: Introduce the capabilities of existing simulation tools and the possible collaboration with other packages.

3. Presentation Structure • 1.Simulation (General) • Definition • Applications • Benefits 2.Simulation products in the market • Types of simulation tools • Top products • Simulation package selection • 3.Extend • General description • Applications • Examples • 4.Simulation Interaction with • other software • Interaction capabilities • Future Development

4. Definition “The technique of imitating the behaviour of some situation or process (whether economic, military, mechanical, etc.) by means of a suitably analogous situation or apparatus, especially for the purpose of study or personnel training”. “Oxford English Dictionary “ “Computer simulation is the process of modelling a system on the computer and then experimenting with the model to answer “what if” questions about the system. It is an excellent decision support tool because it provides a mean of accounting for the stochastic (random) behaviour present in many “real-world” systems such as supply chains, health care facilities, financial services, and production lines”. “Royce Bowden” “Simulation is a discipline not a software package. It requires detailed formulation of the problem, careful translation or coding of the system logic into the simulation procedural language, and thorough testing of the resulting model and results.” “Jerry Banks and Randal Gibson”

5. Applications • Its applications vary from studying systems through statistical estimates or animated operations, to validating analyses ready to be optimised. Applications • Data import/export, spreadsheets, CAD software and databases allow the integration of models with other software. • Input modelling modules can display, summarize and analyze raw data and rank fitted distributions based upon the data (useful for large projects). • It provides access to procedural languages which can be linked to the simulation code (whether C code or Visual Basic), which perform specialized computations, such as scheduling and decision-making within the simulated system. • It allows interaction between World Wide Web. Small manufacturing facilities, communications and transportations networks, service sectors (medical facilities, information processing), military, amusement facilities, e.t.c.

6. Benefits Benefits of simulation models: • Understand basic system operation and throughput capability of the concept design. • Contrast and select the best concept to proceed with the engineering phase. • Determine if the final engineering detail system design from the selected supplier performs differentially than the concept design and if so, why. • Determine the impact on the system throughput of the proposed actual operating procedures once they are available in the engineering detail phase. • Test and validate design changes made during the installation and commissioning phase to determine if they have any unwanted or unexpected impacts. “Jerry Banks and Randal Gibson” • Furthermore benefits are widely appreciated by researchers and modellers such as: • Predict the course and results of certain actions • Understand why observed events occur • Identify problem areas before implementation • Explore the effects of modifications • Confirm that all variables are known • Evaluate ideas and identify inefficiencies • Gain insight and stimulate creative thinking • Communicate the integrity and feasibility of your plan

7. Types of simulation tools Simulation Tools Simulators Simulation Languages Continuous Discrete Event Combined Simulators are modelling programmes that use icons to represent items. Most activities are included in the modelling library, where animation is an integral part and there is very little programming needed. They use common flowcharting symbols to describe the flow of the process. Simulation languages are hierarchical development environments provide the flexibility to model any logical relationships. They can be programmed at the expense of time. Continuous simulations are analogous to a constant stream of fluid passing through a pipe. The volume may increase or decrease, but the flow is continuous. In continuous models, values change based directly on changes in time In discrete event models, discrete entities change state as events occur in the simulation. The state of the model changes only when those events occur; the mere passing of time has no direct effect. Combined applications can model systems either discretely or continuously. These hybrid applications combine all the features of both types of modelling. In this case, you Choose how to model the system based on the level of detail required.

8. Top products • The increased need for simulation tools and the parallel development of software has led to a large number of simulations products in the market. Out of 58 simulation packages the top 10 are: ·SIMPROCESS ·Taylor II ·Extend 4 ·WITNESS 8.5 ·Job Time Plus ·SiMPLE++5.0 ·ARENA 3.5 ·SIMUL8 4.0 ·AutoMod 8.5 1.SIMPROCESS 2.Taylor II 4.WITNESS 3.Job Time Plus

9. Simulation package selection • Methodology 1: It uses a framework, where users can evaluate products in seven areas (e.g., model development, animation) and then decide for the suitable tool, according to the highest score. • Methodology 2: By going through the tools characteristics (application, features, capabilities) and resulting in that one that the purpose of the process that it is asked to simulate. Surveys, published by simulation professionals can provide these data:

10. “Extend” General description Interactive, reusable, and visual tool that accelerates model building and enhances your understanding of complex systems.: • Interactive: Even during a model run, Extend parameters and model logic can be changed "on the fly" rather than having to wait until the simulation ends • Reusable: You can create, reuse, even distribute Extend blocks – the components that comprise a model. Group existing blocks to save them as one hierarchical block. Or develop custom blocks with unique behaviours, icons, and dialogs. • Scalable: Extend is used to produce complex enterprise-wide models. • Visually Transparent: Block icons convey the structure and behaviour of the model at a glance. • Well Connected: Extend supports the component object model (COM/ActiveX) and open database connectivity (ODBC). • Extendable (open source): The blocks are Open Source to allow modification and enhancement. Extend‘ s open source architecture gives you the freedom to model anything. • Global Reach: Extend is so flexible it has become the simulation engine used by most OEM developers and the learning tool used by most educators. Additional Characteristics: • Hierarchy • Open source code modelling components • Integrated development environment • Drag-and-drop user interface • Library-based modelling • Message-based architecture • Modules developed by third parties • Modules developed by third parties

11. Applications • Its applications vary from studying systems through statistical estimates or animated operations, to validating analyses ready to be optimised. • Being a Continuous/Discrete Event/Combined and both a hierarchical and simulator tool it comprises all the applications of those different types: • Small and large manufacturing facilities • Communications and transportations • Networks • Service sectors (medical facilities, information processing) • Military • Amusement facilities • Logistics and • Business processes

12. Examples • Serial Processing 2.FastFood • 3.Simple Batching

13. Interaction capabilities • Data import/export, spreadsheets, CAD software and databases allow the integration of models with other software. A spreadsheet might be used to format and feed data to the simulation model and to analyze the output from the simulation model. • It provide access to procedural languages which can be linked to the simulation code (whether C code or Visual Basic), which perform specialized computations, such as scheduling and decision-making within the simulated system.

14. Future Development • Increase the flexibility and accuracy of data input and design parameters, along with the design environment. • Enhance the integrating capabilities of simulation tools with other software packages (design, statistical or programming), considering the World Wide Web.

15. Conclusions • The applications and benefits of simulation are numerous in many sections. • Careful consideration should be given when choosing the appropriate simulation tool to suit a specific task. • It is essential to be able to translate simulation results into real problems and the other way around, otherwise there is no use in those results. • The collaboration between simulation packages and other analytical or programming packages, or even the development of a compatible, to many other programmes simulation tool, could give integrated solutions that no other package can give.

16. Bibliography • Madewell, C. D., and Swain, J. J., 2002, "The Huntsville Simulation Snapshot: A Quantitative Analysis of what Employers Want Most in a Systems Simulation Professional," Proceedings of the Huntsville Simulation Conference, Huntsville, Ala. • Pritsker, A.A.B., 1990, "Papers, Experiences, Perspectives," Systems Publishing Corp., West Lafayette, Ind. • Pritsker, A.A.B., 1998, "Life and Death Decisions: Organ Transplantation Allocation Policy Analysis," OR/MS Today, August, Vol. 25, No. 4, pp. 22-28. • Swain, J. J., 1995, “Simulation Suvey: Tools for Process Understanding ans Improvement”,OR/MS Today, August, Vol. 23, No. 4, pp. 64-72. • Swain, J. J., 2001, "Power Tools for Visualization and Decision Making," OR/MS Today, February, Vol. 28, No. 1, pp. 52-63. • Bowden R., 1999, “The SPECTRUM of Simulation Software”,SOLUTIONS, May, Vol. 18, No. 3, pp. 44-46. • Imagine that, 2002, “Extend User’s Manual”.