# Computer Models

Topics: Computer graphics, Problem solving, Computer simulation Pages: 13 (1902 words) Published: May 14, 2013
LECTURE 01: MODELLING BASICS Jojo Lartey
Department of Information Technology Methodist University College Ghana Dansoman

11 March, 2013

Jojo Lartey (MUCG)

MUIT 404 Lecture-One

March 2013

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Overview

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L ECTURE O BJECTIVES INTRODUCTION MODEL BUILDING METHODS MODEL CATEGORIES STAGES OF MODEL BUILDING MODEL BUILDING TECHNIQUES SUMMARY

Jojo Lartey (MUCG)

MUIT 404 Lecture-One

March 2013

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L ECTURE O BJECTIVES

Learning Outcomes

Equip you with the basics to modelling and decision making. At the end of this lecture should: become familiar with what constitutes a computer model gain an insight into building model developments understand how models are categorised ”everything should be made simple but not simpler than simple” A LBERT E INSTEIN .

Jojo Lartey (MUCG)

MUIT 404 Lecture-One

March 2013

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INTRODUCTION

How do we understand things we can not visualize?

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What would the weather be like in ﬁve days? How much income can be made from an investment? Which insurance portfolio would have most claims? When will the air conditioner bring this room to 18 ◦ C? What will cereal production level be in 50 years? When will MUCG student population exceed 100K?

Typical questions we can answer with a computer model. They are useful for studying things otherwise impossible.

Jojo Lartey (MUCG)

MUIT 404 Lecture-One

March 2013

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INTRODUCTION

So What is a Model?

A model is a general term denoting any abstraction or an idealisation of a physical system What do models do? Creates concepts as bases for logical analysis. Aim at identifying only signiﬁcant factors and interrelationships of a system or situation. Provide a logical structure to simplify the complexities and uncertainties in problems.

Jojo Lartey (MUCG)

MUIT 404 Lecture-One

March 2013

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INTRODUCTION

...and Computer Models?
A computer model is a computer program that attempts to imitate or mimic a real-life system. A virtual version of something in the real-world. Why settle for an imitation? ... because reality is often too complex to understand completely! Allows detail study of incomprehensible problems. High speed scientiﬁc computers allow us to optimise designs in ways that were unavailable in times past: 1 2 3 4 5 6 7

weather forecasting population growth stock investment performance resource allocation disease transmission molecular dynamics. · · · and many more MUIT 404 Lecture-One March 2013 6 / 25

Jojo Lartey (MUCG)

INTRODUCTION

Usefulness of Models
Unlike experimentation, models provide much easier and cost effective method to obtain information. Facilitate how to determine changes, and causes to these changes, in a system. Access inter/intra entity affects, without imposing changes on these blended entities. A useful approach to explain and predict behaviour of individual components of a problem or system. Its generic in character with an explanatory, rather than a descriptive, purpose. A useful way to provide response to changes in a model’s internal and external disturbances

Jojo Lartey (MUCG)

MUIT 404 Lecture-One

March 2013

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MODEL BUILDING METHODS

Model Building Approach

A scientiﬁc approach is adopted in model building methods What are the determinants of a scientiﬁc approach? 1 2 3

Uses a systematic methodology to solve problems. Includes a certain kind of scientiﬁc experimentation. Hypothesis is tested against created model.

Jojo Lartey (MUCG)

MUIT 404 Lecture-One

March 2013

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MODEL BUILDING METHODS

Objective of a Model
A model will succeed for its use based on how much we know about the problem or the physical system’s state(s) as well as how well the modelling itself is done The objective of a model could be to: i Developing scientiﬁc understanding of the system. ii Gain insight into the system or...