In an increasingly complex world, we cannot always afford to test our ideas in reality. You wouldn’t crash a real Boeing 747 just to see if the landing gear holds up, nor would you shut down a national power grid to test a new solar integration. This is where Simulation and Modelling becomes the ultimate “sandbox.” It is the science of creating a digital twin of a system to predict how it will behave under different conditions. For students, this unit is a bridge between pure mathematics and computer science, requiring both a logical mind and a solid grasp of probability.
Below is the exam paper download link
SMS-3450CIT-3358-SIMULATION-AND-MODELLINGCOMPUTER-SIMULATION
Above is the exam paper download link
To help you move from basic flowcharts to high-fidelity digital models, we have synthesized the core “must-know” topics found in recent examination sittings.
What is the difference between a ‘Static’ and ‘Dynamic’ Simulation?
This is a foundational distinction in every past paper.
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Static Simulation: This is a “snapshot” in time. Think of a Monte Carlo simulation used to estimate the value of $\pi$ or the risk in a financial portfolio at a single moment. Time doesn’t play a role here.
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Dynamic Simulation: This model evolves over time. If you are simulating the traffic flow through a busy intersection in Nairobi or the spread of a virus through a population, you are dealing with a dynamic system where “State $T+1$” depends on “State $T$.”
How do we define ‘Discrete-Event Simulation’ (DES)?
Most computer simulations fall into the DES category. In this model, the state of the system changes only at specific points in time called “events.” For example, in a bank simulation, nothing “happens” mathematically between a customer arriving and a customer being served. The clock simply “jumps” from one event to the next, making the simulation incredibly efficient for computers to process.
Why are ‘Random Number Generators’ (RNGs) so important?
Real life is rarely predictable. To make a simulation realistic, we must introduce randomness. However, computers are inherently logical, so they use Pseudo-Random Number Generators. These are mathematical algorithms that produce a sequence of numbers that look random but are actually determined by an initial “seed” value. In an exam, you might be asked to test the “Uniformity” or “Independence” of these numbers using a Chi-Square or Kolmogorov-Smirnov test.
What are ‘Verification’ and ‘Validation’?
These two terms are often confused but are totally different:
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Verification: Did we build the model right? (Is the code bug-free? Does the math follow the logic?)
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Validation: Did we build the right model? (Does the simulation actually behave like the real-world system it is supposed to represent?)
A model can be perfectly verified but completely invalid if it doesn’t reflect reality.
What is ‘Monte Carlo’ Simulation?
Named after the famous casino destination, Monte Carlo methods use repeated random sampling to obtain numerical results. It is widely used when a problem is too complex to solve with a simple formula. For example, to find the area of an irregular shape, you could “drop” thousands of random points and count how many land inside the boundaries. In your revision, practice using Monte Carlo to solve integrals or estimate project completion times (PERT).
How do we handle ‘Queuing Systems’ in a model?
Many simulations are essentially “Wait-and-Serve” models. You will need to understand the M/M/1 queue notation:
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M (Arrival): Markovian (Poisson) arrivals.
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M (Service): Exponential service times.
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1: A single server.
By simulating thousands of customers, you can predict the “Bottle-Neck” points in a system before they ever happen in real life.
Conclusion
Simulation and Modelling is about the power of “What If?” It allows engineers, doctors, and business leaders to fail safely in a virtual environment so they can succeed in the real one. Success in your finals comes from your ability to translate a word problem into a logical flow of events and random variables.
To help you debug your knowledge and master the logic of system states, we have provided a link to a full set of practice problems below.
Last updated on: March 24, 2026