chap8仿真与虚拟现实

1、System Simulation and VR,Chapter 9 Verification and validation of simulation models,overview,Model building, verification, and validation Verification of simulation models Calibration and validation of models,Model building, verification, and validation,Verification building the model right To compa

2、re the conceptual model to the computer representation that Is the model implemented correctly in the computer? Are the input parameters and logical structure of the model correctly represented?,Validation Building the right model To determine a model is an accurate representation of the real system

3、,Model building, verification, and validation,overview,Model building, verification, and validation Verification of simulation models Calibration and validation of models,The purpose To assure that the conceptual model is represented accurately in the computerized representation. Is the conceptual m

4、odel accurately represented by the operational model?,Verification of simulation model,Verification of simulation model,Assumptions on system components system structure parameter values abstractions simplifications,Suggestions,Make flow diagram Examine the model output for reasonableness under a va

5、riety of settings of the input parameters Print the input parameters at the end of the simulation,Interactive run controller (IRC) The simulation can be monitored as it progresses. Attention can be focused on a particular line of logic or multiple lines of logic that constitute a procedure or a part

6、icular entity. Values of selected model components can be observed.,Input data modeling,Data collection Identifying the distribution with data Histograms Selecting the family of distributions Q-Q plots Parameter estimation Goodness-of-fit tests,overview,Model building, verification, and validation V

7、erification of simulation models Calibration and validation of models,Calibration and validation of models,Validation The overall process of comparing the model and its behavior to the real system and its behavior. Calibration The iterative process of comparing the model to the real system,Naylor an

8、d Finger approach,Build a model that has high face validity Validate model assumptions Compare the model input-output transformations for the real system,Face validity,Make sure the model appears reasonable on its face to model users and others who are knowledgeable about the real system being simul

9、ated.,Validation of model assumptions,Structural assumptions How the system operates Simplifications and abstractions of the reality Data assumptions Should be based on the collection of reliable data and correct statistical analysis,Validating input-output transformations,The model is viewed as an input-output transformation. The model accepts values of the input parameters and transforms these inputs into output measures of performance.,Input-output validation,Using historical input data Using a Turing test,Summary,Validation of simulation models is of great importance Decisions ar