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REVISE EDEXCEL

Edexcel curriculum (2015)


Python

Binary/Hex

Data representation

Compression

Encryption

What is a computer?

Working computer

Hardware

Operating system

Computer processes

The CPU

Memory

Input devices

Output devices

Data storage

Inside the CPU

Stored program

F-D-E cycle

CPU components

Networks

LAN, WAN and PAN

Network topologies

Network addressing

Protocols

Error detection

The internet

The world wide web

HTML and CSS

Client-server model

VPNs

SQL

Impact

Ethical issues

Microcontrollers

Comp models

Emerging trends

Virtual machines

Models and sims

Algorithms


Computational models 


A sequential computational model is one in which instructions are executed one after another. There may be branches in the program, but the general principle is that each instruction follows on from the previous one.

Python programs are sequential.
​
A parallel computational model is one in which each program instruction is executed simultaneously on multiple processors in order to get the results faster. Using multi-cores in processors is an example of parallel computing. It is by using parallel processing that super computers are getting faster and faster.
Picture



​"How many cores will the NSA data centre have?"

​Computational model - Multi-agent 


A multi-agent computational model is one in which computer systems co-operate and co-ordinate with other agents to achieve their goals.

Swarm robots are examples of multi-agents.

Artificial intelligence


What comes to mind when you think about artificial intelligence (AI).?

Game playing: programming computers to play games against human opponents (in May 1997, an IBM super-computer called Deep Blue defeated world chess champion Gary Kasparov in a chess match)

Expert systems: programming computers to make decisions in real-life decisions (e.g. disease diagnosis based on symptoms)
Natural language: programming computers to understand human languages

Neural networks: systems that simulate intelligence by attempting to reproduce connections in animal brains
​
Robotics: programming computers to react to sensory stimuli.
Watson and the Jeopardy! Challenge
What is "The Turing test?"
What is "The chinese room problem?"
Try "Cleverbot"

​Nanotechnology


Fairly soon, we are likely to reach the point where we won’t be able to shrink the size of transistors on silicon microprocessors any more.
When we reach this point, nanotechnology will be needed to create a new generation of computer components.
In the future, nanotechnology could impact on all industries and all areas of society, including: communications, medicine, transportation and agriculture.

DNA Computing


DNA computing is a branch of computing which uses DNA, biochemistry, and molecular biology hardware, instead of the traditional silicon-based computer technologies.

​In every cell in your body there is a nucleus
In every nucleus there is a chromosome
A chromosome is made up of DNA
Picture

​What does DNA do?
DNA carries all of the information for your physical characteristics. (what makes you, you)
The characteristics of you are stored in sections of the DNA called “Genes”. You have a gene for eye colour, height, skin colour etc


Picture
DNA stores data. Your DNA stores data about you. We can manipulate DNA to store any data in the same way we use transistors to store information. Hence the term DNA computing

The main benefit of using DNA computers is that they can solve many complex problems at the same time. This known as: parallel processing. As it is possible to fit 100 trillion DNA molecules into an area less than 1cm3, a DNA computer could hold 100 tb of data and parallel process 10 trillion calculations at the same time.

Quantum computing


What is Moors law?
"Moore's law" is the observation that, over the history of computing hardware, the number of transistors in a dense integrated circuit has doubled approximately every two years.

If Moors law is right, then there will be a time when we can no longer fit more transistors on a CPU we have to look at emerging fields such as quantum computing and DNA computing. Quantum computing Is based on quantum physics

Conventional computers work by processing data stored as bits in one of two states: 1 or 0, Quantum computers encode data as quantum bits (or qubits) which means they are not limited to storing data in just two states. Individual qubits can represent a value of 1 or 0 or both numbers simultaneously. 

Past exam questions


Below is a past paper question. Attempt it before viewing the answer. Goodluck!
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Answer - click here
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        • Programming paradigms
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        • Energy introduced
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        • Conduction, Convection, Insulators
      • 04 - Chemical ideas & reactions >
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        • Chemical reactions2
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