Model validation - IDEF0 diagram

This IDEF0 diagram sample was created on the base of the figure from the website of the Engineering Laboratory of the National Institute of Standards and Technology (NIST). [mel.nist.gov/ msidlibrary/ doc/ kc_ morris/ gsa-final_ files/ image011.gif]
"Verification and Validation of Computer Simulation Models is conducted during the development of a simulation model with the ultimate goal of producing an accurate and credible model.
"Simulation models are increasingly being used to solve problems and to aid in decision-making. The developers and users of these models, the decision makers using information obtained from the results of these models, and the individuals affected by decisions based on such models are all rightly concerned with whether a model and its results are “correct”". This concern is addressed through verification and validation of the simulation model.
Simulation models are approximate imitations of real-world systems and they never exactly imitate the real-world system. Due to that, a model should be verified and validated to the degree needed for the models intended purpose or application.
The verification and validation of simulation model starts after functional specifications have been documented and initial model development has been completed. Verification and validation is an iterative process that takes place throughout the development of a model." [Verification and Validation of Computer Simulation Models. Wikipedia]
The IDEF0 diagram example "Model validation" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the IDEF0 Diagrams solution from the Software Development area of ConceptDraw Solution Park.

This work flow chart sample was redesigned from the picture "Simulation for earthquake disaster assessment" from the article "Simulation Workflows".
[iaas.uni-stuttgart.de/ forschung/ projects/ simtech/ sim-workflows.php]
" This simulation was developed to have an in depth understanding of the destructions and the decisions to be made in various phases of crisis management (Source: Mahdi Hashemi and Ali A. Alesheikh (2010). "Developing an agent based simulation model for earthquakes in the context of SDI." GSDI 12 World Conference. 19 – 22 October 2010. Singapour). The simulation process contains following major steps:
(1) All spatial information including satellite images (before and after the earthquake) and topographic/ cadastral maps of the area are mosaicked and georeferenced. The parts of the city that contain various levels of destructions are selected. Three types of features namely buildings, roads and recreational areas are classified and extracted from the satellite images.
(2) The governing factors of destructions are identified; a mathematical model that integrates the factors is constructed.
(3) The simulation is constructed for various parameter values (different earthquake strength, time elapses, etc.)" [iaas.uni-stuttgart.de/ forschung/ projects/ simtech/ sim-workflows.php]
The example "Workflow diagram - Earthquake disaster assessment" was drawn using the ConceptDraw PRO diagramming and vector drawing software extended with the Workflow Diagrams solution from the Business Processes area of ConceptDraw Solution Park.

This work flow chart sample was redesigned from the picture "Weather Forecast" from the article "Simulation Workflows".
[iaas.uni-stuttgart.de/ forschung/ projects/ simtech/ sim-workflows.php]
"(1) The weather is predicted for a particular geological area. Hence, the workflow is fed with a model of the geophysical environment of ground, air and water for a requested area.
(2) Over a specified period of time (e.g. 6 hours) several different variables are measured and observed. Ground stations, ships, airplanes, weather balloons, satellites and buoys measure the air pressure, air/ water temperature, wind velocity, air humidity, vertical temperature profiles, cloud velocity, rain fall, and more.
(3) This data needs to be collected from the different sources and stored for later access.
(4) The collected data is analyzed and transformed into a common format (e.g. Fahrenheit to Celsius scale). The normalized values are used to create the current state of the atmosphere.
(5) Then, a numerical weather forecast is made based on mathematical-physical models (e.g. GFS - Global Forecast System, UKMO - United Kingdom MOdel, GME - global model of Deutscher Wetterdienst). The environmental area needs to be discretized beforehand using grid cells. The physical parameters measured in Step 2 are exposed in 3D space as timely function. This leads to a system of partial differential equations reflecting the physical relations that is solved numerically.
(6) The results of the numerical models are complemented with a statistical interpretation (e.g. with MOS - Model-Output-Statistics). That means the forecast result of the numerical models is compared to statistical weather data. Known forecast failures are corrected.
(7) The numerical post-processing is done with DMO (Direct Model Output): the numerical results are interpolated for specific geological locations.
(8) Additionally, a statistical post-processing step removes failures of measuring devices (e.g. using KALMAN filters).
(9) The statistical interpretation and the numerical results are then observed and interpreted by meteorologists based on their subjective experiences.
(10) Finally, the weather forecast is visualized and presented to interested people." [iaas.uni-stuttgart.de/ forschung/ projects/ simtech/ sim-workflows.php]
The example "Workflow diagram - Weather forecast" was drawn using the ConceptDraw PRO diagramming and vector drawing software extended with the Workflow Diagrams solution from the Business Processes area of ConceptDraw Solution Park.