Modelling and Simulation Technologies v2

7/31/2019 Modelling and Simulation Technologies v2

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Modelling and simulation

technologies


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We may use models because they are simplerthan reality and because they help us

understand a real life situation better


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What are models?

Representation of a physical object, an idea or

a process.

It is an abstract, mathematical representation

of a real-world object or situation.


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What will be the relationship between modelsand spreadsheets?


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Which aspects are considered relevant in amodel?

Give examples


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What is simulation

It is the implementation of a model

It is the application of a model to see how itperforms

It is used because sometimes it is not possibleto observe the real-life event: star explossion


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In asimulation, a model may behave indifferent ways


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Asimulation requires a model, a model doesnot require a simulation


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Simulation is a virtual experience


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Classification

Models

VisualizationGraphical

representationMaps and charts

Physical3D

representation ofreal-world objects

Used in windtunnels for

aerodynamic tests


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Virtual reality


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Virtual Reality


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Virtual reality

A technology that gives the user the

impression that they are fully immersed in a

computer-simulated environment

The user must wear a special input devices:

headset, joysticks or googles.


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Application areas

Medical training, to explorehuman body

Education

To walk through the construction and test its

design from both inside and outside, test thelightning conditions

Architecture

Complex mechanical parts can beexplores in 3D

Engineering

For flight simulation trainingTraining

Realistic computer gamesEntertainment


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Augmented reality


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Augmented reality


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Augmented reality


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Augmented reality

It is a technology that sumperimposes a

computer-generated image (CGI) over the

real-world image


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Wearable gestural interfaces

The computer

generates onto the real

world objects

The FU interacts with

the CGI and can get info

from it


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Augmented Reality Glasses

Allow light to pass to

the eye while at the

same time acting as

information screen

Devices that tallow to

see people, labels or

texts


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AR in Smartphones

AR programs that

contain an integrated

movement screen and

camera

Can help in navigation

to determine the

direction and distance


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AR in television sports

CGG sumperimposed in

fields to trace

movement

Help for jurors


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AR maps

Satellite images can be

augmented with extra

information from the

Internet and CGI ofbuildings and roads


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When are 2D and 3D used?

Maps, charts, graphs

Zoom in/out,

Move horizontally/vertically2D

PC screen is 2D. It cant display 3D.

Required specialized glasses with polarized

filters. Offer more info than 2D

Has more freedom. Another persective

Increase image realism

3D


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Importance of simulation

Large amount of data

Presented for humans

?

Graphic and images


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Importance of simulation


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When a model is valid?

It depends on the purpose or the perspective

Which elements are valid to simulate the

decoration of your room?


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It depends on the purpose or the perspective

Which elements are valid to simulate the

lightning of your room?


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Verification

It must be verified against

the real world

Check if the modelcorrespond to the reality

Simulation in scale model,

adjusted to computermodels

Reliability

Interaction is considered.

How the factors iteract

between them?

Assumptions: the consideredfactors were randomlyselected? Or accidentallyexcluded?

Starting parameters,otherwise it may workincomplete or not accurate


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Can we predict the weather in advanced (7

days)?

Factors change constantly every day:

Humidity, air pressure, temperature, winds.

Forecasters run simulation several timeschanging factors, according to results they

publish them


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Faulty and hidden assumptions

Relevant

It may create a big project

Too difficult to create

Improve the final result

The real world is complex, it is impossible toconsder all the factors

?


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An engineer assumes the color of a metal

bridge is not relevant to the stability of the

structure.

He keeps out the color of the model.

Is that right?


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Assumptions!

Assumptions!

Assumptions!

Unexpected results!


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Problem: color can influence the temperature.

Darker colors absorb more light, causing the

metal to expand


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If the engineer inputs wrong or incomplete

data: wind speed, water currents.


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If the engineer inputs wrong or incomplete

data: wind speed, water currents.

CRASH!! CRASH!!

Faulty assumptions


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Problems of simplifying reality

A computer simulation may consume too

much computation time.

Be done carefully

Risky and chaotic behavior!

Some systems are difficult to predict


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Problems of simplifying reality

Documents

Modelling and Simulation Technologies v2