National 5 – Calculations

  • Size of bitmap = no. of Horizontal pixels X no. of Vertical pixels X Colour Depth
  • No. of pixels = DPI X size in inches

You should also be able to convert from bits, Bytes, Kilobytes, Megabytes, Gigabytes & Terabytes.

  • Bit= 1/0 (Binary digIT)
  • 1 Byte = 8 Bits
  • 1 Kilobytes= 1024 Bytes  (210)
  • 1 Megabytes= 1024 KB  (220)
  • 1 Gigabytes = 1024 MB  (230)
  • 1 Terabytes = 1024 GB  (240)

For colour depth

  • 8 bits = 256 colours (28)
  • 16 bits = High Colour 65,536 colours (216)
  • 24 bits = True Colour 16,777,216 colours (224)

N5 – Easter School

You can find the resources used in this year’s Easter school in the classroom OneDrive area. We will go over them in class as well but I thought you might be lacking for something to do. Enjoy your holidays.

 

N5 – Technical implementation (storage)

Some of you were concerned that I had missed something that was on your revision sheets, so I thought I might revisit it here. In the previous post I had decided to reorganise this section, which wasn’t reflected in the CAS.

Description and exemplification of the appropriate type of storage required for a specific information system including:

Type of device

It is important to pair the correct type of device with a specific information system. Systems that require a lot of storage like video or image libraries often prioritise this over very fast access to a hard drive is used. While systems that require fast access like video editing will make use of solid state devices.

Capacity

The rule of thumb with capacity is bigger is better, however, this can come at a substantial cost. It is therefore important to understand the needs of the IS, a server will require subtancialy more capacity than a presentation for example.

Interface type

Portable Information Systems will require USB ports to connect to. Some IS devices may make use of wirelesss connections. The computer must have the same interface as the IS device.

N5 – Coding

Description and identification of coding to create and modify information systems including JavaScript mouse events.

Javascript is used in HTML documents to add interactivity. The HTML file below has a number of interactive elements to it. Use notepad++ to investigate it further.

<!DOCTYPE html>
<html>
<head>
<title> Teacher Example  </title>
<!--     
The <script> in the <head> tag allows the functions to be called from 
anywhere in the document
-->
<script>

<!-- Changes Style on Mouse Over -->
function mouseOver() {
document.getElementById("demo").style.color = "red";
}

<!-- Changes Style back after Mouse Over -->
function mouseOut() {
document.getElementById("demo").style.color = "black";
}
<!-- Asks for and displays a name -->
function myFunction() {
<!-- Asks the user to enter their name -->
    var person = prompt("Please enter your name", "Harry Potter");
	<!-- Displays the persons name in ID demo3 -->
    if (person != null) {
        document.getElementById("demo3").innerHTML =
        "Hello " + person + "! How are you today?";
    }
}
</script>

</head>

<body>
<!-- Display a heading that can be changed later -->
<h1 id="demo" onmouseover="mouseOver()" onmouseout="mouseOut()">Welcome</h1>

<!-- Displays a button that when pressed will display the date in the first Heading-->
<p>
<button type="button"
onclick="document.getElementById('demo').innerHTML = Date()">
Click me to display Date and Time.</button>

<!-- Uses Javascript to display the message "Your Text Here" -->
<p>
<script>
document.write("Your Text Here");
</script>

<!-- The text RESULT is not displayed as it is replaced by 
     the results of the calculation below it-->
<h1 id="demo2">RESULT</h1>
<script>
var price1 = 5;
var price2 = 6;
var total = price1 + price2;
document.getElementById("demo2").innerHTML =
"The total is: " + total;
</script>

<!-- This button calls the function myFunction from above -->
<p>Click the button to demonstrate the prompt box.</p>
<button onclick="myFunction()">Try it</button>
<p id="demo3"></p>

</body>
</html>

Description, exemplification and implementation of coding to create and modify information system including the use of HTML with the tags for:
o Document
o Links
o Graphics

The documents below show a HTML document with the basic html document tags and a document showing the html tags for links and images 

<!DOCTYPE html>
<html>
<head>
<title> </title>
</head>
<body>

</body>
</html>

<!DOCTYPE html>
<html>
<head>
<title> Page1 </title>
</head>
<body>
<h1>Example of a heading of type 1</h1>

<h2>And this is heading 2</h2>

<!-- The anchor tag <a> is used to link a html document to another document. 
     The href attribute gives the name of the destination of the link. -->
<p>Here is a paragraph of text,
which includes a link to <a href="page2.html">page 2</a></p>

<p>
<!-- The image tag <img> is used to display an image.
     The src attribute is the name of the image -->
<image src="logo.png">

</body>
</html>

Technical Implementation (software requirements)

operating system platform required  
An Operating system is required to allow all parts of a computer system to communicate with each other and with the user.
Describe the purpose of an operating system including:  
controlling peripherals  
The OS controls the Input and Output to attached peripherals using device drivers.
running software  
The OS schedules software access to the processor, this allows several pieces of software to appear to run at the same time. Example Word-processing while listening to music.
HCI  
The Human Computer Interface is how the user and the operating system communicate with each other. The two main types of HCI are command line where the user types command and graphical where the user runs applications and command using icons and a pointing device.
Understand the features of web browsers including:  
OS support  
Web browsers are often available for different operating systems. This allows the for the same browser experience on different platforms.
privacy modes  
Most modern browsers have a privacy mode that clears browsing history and downloads from the computer at the end of the session. This is useful if you are trying to buy a gift and want it not to show up in your browser history.
Ad filtering  
Browsers have the ability to block adverts, this can either be in the form of a pop up blocker or an extension that removes adverts from the pages. This might cause problems in the future as websites are ran by companies who need to make a profit to pay for the website.
page zooming  
Some people require fonts etc. to be a little bit bigger to make them easier to read. Web pages can therefore be zoomed to increase the size of hard to read content.
Description and exemplification of the appropriate type of software required for a specific information system including:  
type of application  
Word processor, spreadsheet, database, multimedia, presentation, web page authoring software, games.
operating system  
Before buying or using an application you need to make sure that it is compatible with the operating system used on the computer.

N5 – Technical implementation (networking/ connectivity)

stand-alone or networked
A stand-alone computer is not connected to any other computer.

A network computer is connected to other computers via a network, this can be either wireless or wired
LAN/internet
Local Area Network – This a network of computer in a small geographical area, such as a building.

Internet – This is a worldwide network of computer networks.
Description and comparison of the following transmission media in relation to data speeds and ease of use:
wired
A wired network connect is fast connection, which makes use of copper cables to connect to other network devices. This type of network is used for LANs as it has a short range.
optical
Optical networks use fibre optic cables to connect devices together. The data is transmitted as a series of light pulses. Different colours can be sent of the same cable allowing for more than one piece of data to be transmitted at once. Optical networks have the largest range and are often used in undersea cables.
wireless
Wireless networks allow network data to be transmitted without a dedicated wire. The most common are Wi-Fi and Bluetooth. Wi-Fi has the largest range and fasted speed but Bluetooth is the most energy efficient.
Description and exemplification of hardware required for network connectivity including:
Network Interface Card
A NIC is used to connect a device to the network, these can be wired or wireless. The NIC makes sure that the device’s data is

Wireless NICs are often in the form of a USB dongle that can be plugged into any computer or device.
Router
A network router is used to connect one network to another. We use routers to connect our house networks to the Internet. Home routers often have Wi-Fi built in as well as a network switch.
Hub
A network hub is used to connect computers together in a network. Hubs are used in star networks where all the clients share the same bandwidth.
Switch
A network switch is used to connect computers together in a network. Switches have high bandwidth and each device has a direct switched connection to each other.
Description and exemplification of the appropriate type of network connection required for a specific information system including:
Hardware
To connect two or more computers in the network you would need.

·         A NIC for each computer

·         A network hub or switch

·         Cables for a wired network.
transmission media
Transmission media is the connection between two network devices.

·         Wi-Fi & Bluetooth – Wireless radio signals

·         Optical – Fibre optical cables

·         Twisted Pair – Copper cables that are twisted around each and plug into NICs