[joshua7]

a) Describe the 4 listed approaches to Selection.
– roulette wheel selection is when we spin the roulette to randomly select the parent
– stochastic universal sampling is very similar to the roulette wheel selection, only difference is that there are multiple fixed points instead of one
– tournament selection is when we compare two different randomly chosen parent at a time, whichever is better in terms of fitness or survival, it goes to the next round until one remains
– truncation selection is a method of selective breeding as we select animals/plant traits to be bred for the next generation

b) Discuss the characteristics of a good selection approach
– Is able to reject a large number of under-qualified candidates, such as extremely low fitness levels
– It continuously enhances examining pass rates, efficiency, accuracy, and fairness
– Is able to create diversity
– It meets the requirement and situation to assure accuracy and efficiency

[joshua7]

In general terms what is the meaning of the term resource?
– In general resource means all the materials/stuff available around us that can help us satisfy our needs and wants.

Choose any 3 key resources within a computer system and describe the impact if the resource is limited. If applicable, describe how the operating system plays a role in sharing the given resource
– Ram, if ram is limited, then the system will switch to virtual memory which is much slower. It also effects the amount of processes that can be done simultaneously.
– CPU, if cpu is limited, then the processor will take a longer time to carry out the tasks.
– Hard disk, if a hard disk is limited, there wouldn’t be enough storage to save work so it would limit the amount of things that can be saved.

[joshua7]

1. Image and audio files
2. The difference between lossy and lossless compression when used to download files are data. Lossy compression reduces the file size by deleting the data in the file. The lossless compression on the other hand does not delete them, but rather stores data differently. Instead of deleting, it simplifies the data so that it is easier to be processed by packing redundant data. The similarities are that it takes less time to download and takes up less storage.
3. The first factor is the importance of the data and whether losing it would be a big risk. If the file is important, then lossless compression would be the better choice.
Another factor is the speed of the file to be transferred at. If a file needs to be transferred fast, lossy compression would be the better choice.

[joshua7]

1 ) Describe with an example how run Run Length Encoding can be used to compress an image
– Run length encoding is a lossless data compression and it compresses data by reducing repetitive data known as runs. Then it stores the number of these runs followed by the data. So when compressing an image, the RLE would replace each row with numbers that says how many consecutive pixels are the same colour and it must always start with the number of white pixels. For example, if an image is black and white colors, it would replace the the pixels with a number that represents how many of the consecutive pixels or white or black.

[joshua7]

1) What Is File Compression? Why Is It Necessary To Compress Files?
– It is when the file size is reduced to use less storage than the original file. It is reduced by re-encoding the file data.
2) describe the differences between lossless and lossy compression and give examples
– Lossless does not completely eliminate data, including unnoticeable data, so the file can be restored in the original form. Whereas the lossy compression eliminates data, including unnoticeable data, so the file cannot be restored or rebuilt into it’s original form
3) Give examples of lossy and lossless image and video file formats
Lossy
– JPEG, MP3, MP4
Lossless
– PNG, WAV, BMP

[joshua7]

INTLIST = [4,3,5,6,1,9,0,9,7,4,7,8,9,0]
FRQ = […,…]

for i from 0 to 8 /// loop through the array
count = 1 /// sets the integer occurrence as 1
for j in range i+1
if INTLIST[i] = FRQ[j] /// checks if the numbers are the same
count = count + 1 /// Counts the number of occurrence
number = i
occurrence = count
FREQUENCY = (number, occurrence)

Output FREQUENCY

[joshua7]

TENNIS = [“Al”,”Bobby”,”Carla”,”Dave”,”Ellen”
BBALL = [“Lou”,”Dave”,”Hellen”,”Alan”,”Al”]

for Tennis from 0 to n-1
for BBall from 0 to n-1
if TENNIS[] = BBALL[]
Output Tennis[]

[joshua7]

That identifies 4 components specific to setting up a VPN can be a mix of hardware and protocols.
– data encryption
– authentication
– vpn router
– Secure Socket Tunneling Protocol (SSTP)

Briefly describe how VPN’s can be used and how they have impacted working life and social life.
By having vpn, we can access different contents that are blocked based upon our locations (such as netflix or ecommerce sites that are only available locally) and also be able to access different servers at school or offices safely. This let us have access to more resources at work and more variety of entertainment as well as information on different places during our social life. Another use is protection of our data. Having a vpn would allow us to safely use public wifi. It is easy for hackers to intercept the network so by having a vpn, even if it is intercepted, our data would be scrambled thus unable to gain our data. This applies to even when we are simply browsing the internet as many websites gather information to make targeted ads, especially ecommerce or social media. Using a vpn will ensure the safety of our data and prevent targeted ads which will gove us a more seamless experience.

[joshua7]

1. Human interaction with the computer system includes a range of usability problems.

(a) Define the term usability. [1]
– How easy it is for users to use the system

(b) Identify two methods that could be used to improve the accessibility of a computer
system. [2]
– Braille keyboard for someone that is blind
– Text to speech for someone that may have difficulty on using the computer physically

4. A small hotel buys a software package to manage their bookings.

(a) Describe two types of documentation that should be provided with the software package. [4]
– FAQ documents with the most frequently asked questions that the users may have as well. These documents would also contain additional information for help like customer service support contact
– Printed manuals which is a paper manual that explains the basics of the software and provides the first steps like how to install the software and use them

(b) State two methods of delivering user training. [2]
– Self instruction
– Formal classes

7. A hardware shop supplies a wide variety of bathroom equipment. There are 15 shop assistants who serve customers, 3 office staff who handle the administration, and a manager.
A specialized company is asked to design and implement a new computer system for the shop.

(a)
(i) Identify two different types of users of the system. [2]
– Shop assistant
– Office staffs

(ii) Explain the role of users in the process of developing the new computer system. [3]
– The role of users is to make sure the developers of the software are designing the software in the right direction and making sure they understand all the specifications and needs required. Users usually give feedback on prototypes in which the developers can make iterations and edits before making the final software. This process would reduce issues and will ensure user satisfaction for the final product

(b) Describe why it is useful to produce more than one prototype of the new system. [2]
– Multiple prototypes provide safety for developers because of the variety of the options for users but also if the prototype data is lost, there is a backup to ensure that the developer would not need to start again from scratch. Having a variety of prototypes allows users to discover different designs and provide the best feedback to the developers so that the developers have a more clear vision on how to better develop the software

(c) Outline two problems that may occur when transferring data from the old system to the
new system. [4]
– Data loss because during the transfer of data between two systems, many errors such as human error or data incompatibility would result in a data loss. Data loss would have many issues for the software as glitches and software crashes may happen
– Data incompatibility with the new system. The data may not be compatible with the new system for various reasons such as outdated files or data with different components. So during the transfer of data, if it is not compatible with the new system, data would be lost

The new system is implemented using parallel running.

(d)
(i) Outline what is meant by parallel running. [2]
– It is when both the old and the new system are run simultaneously. This process allows a fallback to the old system if the new system fails or needs iterations

(ii) Outline one reason for choosing parallel running as opposed to a direct changeover. [2]
– If the new system fails, parallel running gives the opportunity to fall back to the old system while the new system is being fixed. But also because it reduces the risk of data loss

2021 Paper

12 A school has a cabled network and wishes to add wireless networking access for the whole campus.

Describe 2 hardware components the school will need to implement the network
– Routers connect directly to a modem by a cable and allows it to receive and transmit information to the internet
– Repeaters receives existing signals from a wireless router and rebroadcast it which allows an extended range of the network

Identify 2 advantages to the students of the new wireless network
– It allows more devices to be connected and also allows more convenience as students are able to access the network everywhere within the campus as there is more coverage
– There is also an increased efficiency and improved data communications which allows faster transfer of information within the network

The wireless network connection will remain strong wherever they go due to the presence of the repeaters. This will also allow for more flexibility and portability for the students.
There are concerns that unauthorized people may gain access to the data on the network

(c) Outline 2 methods that the school could employ to prevent network data being accessed over the wireless network.
– Firewall as it acts as a barrier between the school network and external networks as the firewall would control the traffic
– Role based access would allow the school to assign roles to different devices based on how it was authenticated

[joshua7]

1D array part b (used the proper loop)

loop i from 0 to n-1 /// iterates through the 1D array
if inventory[i] < 10 /// Checks if inventory is less than 10
then prices[i] = prices[i]*1.2 /// applies the 20% discount

end loop

[joshua7]

1D array part b

for i[1] to n-1 /// iterates through the 1D array
if inventory[i] < 10 /// Checks if inventory is less than 10
then prices[i] = prices[i]*1.2 /// applies the 20% discount

end loop

[joshua7]

Temp = [23.1,…]
int highest = T[0]
int lowest = T[0]

for T[1] to n-1 /// iterates through the 1D array
if T[i] > highest /// Checks to find the highest
max = T[i]
else if T[i] < lowest /// Checks to find the lowest
min = T[i]

end loop

print (highest – lowest) /// prints the range (high – low)

[joshua7]

Set SURNAME to 0
Set FIRSTNAME to 0
i = 0
NAMES.resetNext()
loop while NAMES.hasNext() = True //looping through using a while loop
SURNAME[i] = NAMES.getNext(). //stores the Surnames in a different array
FIRSTNAME[i] = NAMES.getNext(). // stores the First Names in a different array
i = i + 1
end loop

[joshua7]

Review Activities

1) Discuss the differences between usability and accessibility.
– Usability means how easy the software is to use for a user. Accessibility means how well a disabled individual is able to use software/gadgets.

2) List 6 examples of assistive technology.
– Braille watch
– Eye tracker (using eyes as mouse)
– Speech to text
– Closed captions
– Hearing aids
– Image recognition

3) Select an operating system, example Windows 10 and describe the accessibility features for vision and hearing. Link for Windows 10, but you may choose a different operating system https://www.microsoft.com/en-us/accessibility/
– On android, there is a google camera which is meant to help recognize images using google AI assistant and read aloud what the object is. There is also a magnifying feature on android, both of which are meant to help with vision. For hearing issues, there are a text to text feature using google AI to help users with hearing disabilities to communicate with the google assistant and also includes closed captions on different apps.

4) What is neurodiversity?
–It refers to the variations in one’s experience, interaction with, and interpretation of the world in unique ways. It is a viewpoint that brain differences are normal, rather than deficits

5) Briefly describe some ways that the operating system selected in 3 above caters for neurodiversity.
– Apple’s Watch OS has a machine learning capability which learns the way we text, in order to suggest what we would likely say next in order to help users to type less. It also has a health feature which recognizes your health patterns and sleep patterns to suggest better workout routines or suggests bed times. It also studies the way you interact and displays the most used apps at the center for easier access.

6) Choose a device and identify a range of usability problems that can occur in that system. Device can be PCs, digital cameras, cell phones, games consoles, MP3 players or other commonly used digital device
Cell Phones
– Weak hardware and screen (cracks and breaks with multiple drops)
– Short battery life and sometimes long charge time
– Fails to backup regularly to cloud storage and also data losses sometimes while backing up

7) Select a system from ticketing, online payroll, scheduling, voice recognition. For selected systems identify a range of usability problems that can occur in your system.
Ticketing
– Delay response times leads to crashes that stops the users from reserving a specific seat
– When purchasing tickets, system glitches often lead to wrong seat assignments (suddenly changes)
– During payment process, credit cards are not always accepted
– Receipt of ticket may failed to be sent out

8)For the moral, ethical, social, economic, and environmental implications of the interaction between humans and machines. For each one briefly discuss the pros and cons
– Moral: People are more educated with machines allowing everyone equal education. However, these machine robots are also used in warfare to kill humans.
– Ethical: More information is available, especially on the web which makes information decentralized. However, there has been a large spread of fake news and information.
– Social: It has allowed people to be more connected at a global scale. However, cyber bullying and “influencers” have created negative impacts on the younger generations mental health.
– Economic: It has provided more jobs like software engineers, online content creators, etc. However, these machines have also been replacing jobs like cashiers and labor workers with robots and different gadgets which leads to loss of jobs for certain people.
– Environmental: It has helped us to use machines to promote more environmental campaigns but also new technology allows solutions to environmental issues, like a new machine that can suck out greenhouse gas from the atmosphere or recycling machines. However, it has caused us to use more energy to run technology, which increases fossil fuel consumption which ultimately leads to more pollution. Also E-waste has become a rising issue

[joshua7]

System backup
What is data redundancy and how can it be used to prevent data loss.
– It is when there are two identical set of data stored in a different or same server. This helps prevent data loss as there is a backup for the data, which is the second set of data.

Activity A list a range of causes that can result in data loss. Choose 4 and explain by giving an example. Example user error.. User hits exit without saving and suggest how that might have been prevented
– Computer theft – An employee leaves a laptop unattended at a local cafe. Someone comes and takes the laptop so all the data on the laptop is lost. It can be prevented by carrying the laptop at all times or leaving it attended.
– Virus and Malware – A user accidentally opens a spam email which ends up getting his computer a virus. This can be prevented by never opening spam emails and having regular updates to protect data.
– Natural disaster – A user has a computer in their home with all the data. It ends up being broken when a tornado hits. This can be prevented by backing up data in a cloud or a remote location.
– Hardware/System malfunction – While the user is using their computer, the hard disk crashes and all data is lost. It can be prevented by having regular backups in a cloud or an external harddrive and also making sure the computer is up to date and taken good care of.

Activity B Using an example other than school records outline the consequences of data loss.
– An investment firm stores all transaction details for SEC filings. When this data is lost, all records of transaction details are lost resulting in inability to file to the SEC. This would lead to an investigation by the SEC where the firm could be charged fines, prison time or even lose their license to trade.

Activity C You have been tasked with Implementing a set of procedures to limit the risk of data loss. Details these with an explanation of why they are necessary ( use the same scenario) as in Activity B
1. Having a consistent and regular backup to the cloud. This is to ensure that the data is also kept somewhere safe.
2. Making sure that the software and the hardware are all up to date. This is to ensure that there wouldn’t be any malfunctions.
3. Having a backup system so that if the current system fails, the backup system can kick in which would allow it to have a less amount of data loss as the new data could be imputed straight into the backup system.

Components of a computer system
Past Paper Question

A small company has a LAN connecting its various desk-top computers and peripheral devices.

The company is going to provide Internet access to its LAN.

(a) State the name of an additional hardware device that would be required to permit
Internet access. [1 mark]
Hub

(b) Explain how a firewall would help to provide security for the LAN. [3 marks]
– A LAN network would typically allow every computer to access each other. Having a firewall means that without a key, others would not be able to access it. This would prevent unauthorized access which will ensure security.

(c) Suggest, with reasons, two further measures that the company should take to safeguard its data from unlawful access via the Internet. [4 marks]
– Use a VPN to ensure all activities done on the internet are encrypted and to prevent potential malware.
– Computers should only be used by employees for professional purposes. This would prevent employees from downloading certain things from the internet.
– Have a strong firewall to help increase security

Q What hardware component is needed to extend a LAN to a WAN?
– Wireless router

Q Outline 3 key differences between a Switch and a Router.
– A router allows the system to access the internet, while the switch only allows access to a specific LAN.
– A router connects to various networks simultaneously, while the switch connects to various devices simultaneously.
– A router uses IP address while the switch uses MAC address.

Q What is the key difference between a HUB and a Switch?
– A switch uses the IP address of the data packets to ensure that the data is sent to the correct device, however the HUB sends the data packets to all connected ports rather than to the correct device.

Q We looked at hardware components to set up a LAN what are the hardware components need to set up WLAN
– Wireless routers and access points

[Author]

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