Algorithms

Algorithms - An unambiguous set of steps, which when performed correctly by a processor, will result in a process being carried out in a finite time.

In other words, it is a specific set step-by-step instructions that are used to accomplish a task.



An example of an algorithm would be making a cup of coffee.

1. boil the water,
2. place coffee in the cup,
3. place sugar in the cup,
4. add the boiling water,
5. add milk,
6. stir.



Q1) Examine the algorithm above. What two properties of the algorithm enable it to correctly describe the solution to the problem of making a cup of coffee? What is it that makes an algorithm correct?(Hint: what would happen if you swapped step "6" and step "2"?)



-The order of each instruction in an algorithm enable it to correctly describe the solution. If those steps were to be executed in any order, it wouldn't be able to properly complete the task.

- Precise intructions. If the method wasn't clear, then making a cup of coffee wouldn't be possible.



Q2) Define Algorithms for the following processes:

Posting a letter-

1. Get a paper to write on
2. Think of what you want to write in the letter.
3. Write the date on the top of the page. (preferrably to the top right)
4. Write the recipent's name and address below the date.
5. Leave some space below the recipent's address.
6. Start writing the letter with a proper greeting such as "Dear" or "To whom it may concern"
7. Write an opening paragraph. Asking "how are you?" if it's a casual letter. If it's a business letter, go straight to the point that you want to discuss with the recipent.
8. Write the body of the letter.
9. Write the conclusion of the letter.
10. Write the closing of the letter like "yours sincerely" or "love from" then write your name and signature.
11. Write your adress in the back of the envelope and write the recipent's address in the middle of the front of the envelope.
12. Go to the post shop, then purchase a stamp.
13. Stick the stamp on the envelope.
14. Give the letter to the person working in the post office, or drop it inside the postbox.


Making toast-

1. Get the toaster and plug it in the powerpoint.
2. Go to the fridge and get the bread that you want to toast from the fridge.
3. Put the bread inside the toaster and turn on the toaster.
4. After the bread has popped out of the toaster, or if your toaster makes a "ding" sound, take the bread out and put it on a plate.


Calling a friend on the phone-

1. Think of which friend you want to call.
2. Find your friend's phone number from the phone book.
3. Dial your friend's number on the phone.
4. If your friend's family member answers the phone, ask politely for him/her.
5. Talk to your friend.

Computing anywhere, anytime!

A netbook is a laptop that is smaller and more portable. It is mainly used for surfing the internet because of its computing power. It doesn't have the hard disk drive capacity that desktops and laptops have. Therefore, it is used for the internet and running web-based applications. Netbook users like the feeling of 'freedom' because of its portability. Netbooks are also more affordable than laptops with a price ranging from $200 - $500.
The major drawbacks of netbooks are:
-minimal strorage (small amount of RAM and HDD)
-Low-power CPU's
-Cramped keyboards
-Small screens

Cloud computing is computing with all the resources and services made available through the internet. The term "cloud" is used as a metaphor for the Internet, based on how the Internet is depicted in computer network programs, and is an abstraction for the complex infrastructure it conceals.

The applications that google docs offer online are word processors, spreadsheet, presentation and form applications.
Documents stored online on google docs are more convenient to share with other people and does not need to be stored on the computer.

The advantages that students and teachers find in google docs is that it is more easier to submit documents because it is done online. This means that printing, attaching to emails, downloading word documents and other methods for sharing are not necessary.

I don't really have a netbook to suit my needs because I have a tendency to download a lot of files and install a lot of big programs. I don't really require portable computers because I normally stay in one spot.

Internet addresses activity

1) URL(Uniform Resource Locator)- The address of a webpage/website on the internet.
2) IP(Internet Protocol) Address- An address that is a numerical identification (logical address) that is assigned to devices participating in a computer network. It is the number equivalent to the network.
3) Given our school website's URL is http://www.mcauley.nsw.edu.au, the domain name is mcauley.nsw.edu.au. The protocol that is needed to access the site would be Hypertext Transfer Protocol.
4) An octet is the four numbers in our IP addresses. They are called octets because they have eight positions when viewed in binary numbers. If all positions are added together, it would equal to 32. This is why IP addresses are considered at 32-bit numbers.

Determine your IP address

1) An octet is the four numbers in our IP addresses. They are called octets because they have eight positions when viewed in binary numbers. If all positions are added together, it would equal to 32. This is why IP addresses are considered at 32-bit numbers.

2) The class of IP address that we are using is Class C. IP addresses with a first octet from 192 to 223 are part of this class. Class C addresses also include the second and third octets as part of the Net identifier. The last octet is used to identify each host.

Web 2.0

Web 2.0 is a second generation of the internet which refers to web-based applications that allows users to communicate, collaborate, share information and inter-operate online without the need for installed programmes on the computer. Web 2.0 isn't just one program, it's the internet itself; it's the generation of the internet.

In other words, anything can be done using the internet.

An example of web 2.0 is Google Docs.
It is a free web-based word processor, spreadsheet, presentation and form application offered by google. In other words, google docs allows users to create word documents, spreadsheets, etc online without the need of microsoft office.

Flickr and Photobucket is also a good example. It allows users to share media online.

Websites such as Picnik is a web-based application for editing photos without the need for programmes such as Photobucket.

Blogger and Livejournal is a blogging application and can be used for various purposes:
-Personal (Diary or commentary by an individual)
-Corporate (For business purposes)
-Questioning (Used to answer questions)

Youtube is a popular website which allows users to share videos online.

The internet is evolving and the examples that I have listed shows that. The things that we are capable of doing now wasn't available 10 years ago. Web 2.0 is a new generation that describes the internet, we can see how fast our technology is moving forward.

Key Terms

1) Protocol- rules determining the format and transmission of data

2) TCP/IP(Internet Protocol Suite)- Set of communications protocols used for the internet and other similar networks.

HTTP(Hypertext Transfer Protocol)- A protocol to transfer hypertext requests and information between servers. It is an application-level protocol for distributed, collaborative, hypermedia information systems. Its use for retrieving inter-linked resources led to the establishment of the World Wide Web.

SMTP(Simple Mail Transfer Protocol)- The Internet standard protocol for transferring electronic mail messages from one computer to another. SMTP specifies how two mail systems interact and the format of control messages they exchange to transfer mail.

FTP(File Transfer Protocol)- A network protocol used to exchange and manipulate files over a TCP computer network, such as the internet. FTP is the simplest way to transfer files between computers. It is used to upload web page files from one computer to another.

3)GUI(Graphical User Interface)- An type of user interface which allows people to communicate with electronic devices (such as computers, mp3 players, portable media and gaming devices) through the use of images rather than just text and numbers.

4) There are two methods of data transmission:

Serial- Sends data one bit(binary digit) one at a time along a single communication path.

Parallel- sends the bits simulataneously, resulting in a fast communication speed, but does not work well over long distances.

5) URL(Uniform Resource Locator) - The internet website address.

6) Error detection is the way to detect errors caused by noise or impairments when transmitting data to the receiver.

7) A common method of error detection is checksum. A checksum of a message is an arithmetic sum of message code words of a certain word length, for example byte values, and their carry value. The sum is negated by means of ones-complement, and stored or transferred as an extra code word extending the message.
On the receiver side, a new checksum may be calculated from the extended message. If the new checksum is not 0, an error has been detected.

8) HTML(Hypertext Markup Language) is the most common markup language used for webpages. It designs the layout and structure of text-based information. It is important because it gives webpages their structure. Without it, information would be displayed as plain, with no layout at all.
Examples of HTML include :
BOLD
Italics
Underline
Strikeout

Pararaph

HTML is written in "tags" surrounded by angle brackets

History of the internet

1) The internet originated when the United States formed the Defence Advanced Research Project Agency (DARPA) secure their lead technology. They developed what was known as ARPANET, which was a large scale computer network to transfer information. Three other network concepts was developed: RAND Corporation (military network), National Physical Laboratory (commercial network) and Cyclades (scientific network). All four of those network concepts were the origin of the internet.

2) The people who were responsible for creating the internet was DARPA, RAND Corporation, National Physical Laboratory and Cyclades.

3) The system that immediately preceded the internet was ARPANET. It was created for the purpose of information tranfer and to avoid doubling up of already existing research.

4) An IP Packet is a formatted unit of data that is sent through a packet mode computer network. Data is formatted into packets to avoid congestion when being transferred from computer to computer. IP Packets are comprised of a header and payload(user data).

5) TCP stands for Transmission Control Protocol. It uses a sequence number to identify every byte of data. It distinguishes the order of each byte as they are sent from a computer so that they can be transferred reliably. By doing so, lost packets can be identified and retransmitted by the sender.

Bits and Bytes

For this activity, we are to go to the website:

http://computer.howstuffworks.com/bytes.htm/printable



and read about bits and bytes.



Q1) Digit- A digit is a single place that holds any number between 0-9.

Digits are combined to form bigger numbers such as 57646, which contains 5 digits.



Q2) Base-10- Also known as the decimal number system. It is a numerical system in the powers of 10.



Q3) Where does the word BIT originate from?

Bit is shortening of the two words: Binary digIT.



Q4) If 6,357 can be written as;
(6 * 1000) + (3 * 100) + (5 * 10) + (7 * 1) = 6000 + 300 + 50 + 7
How would you write 4,321 ?

(4 * 1000) + (3 * 100) + (2 * 10) + (1 * 1)



Q5) 10100 (base 2) = (1 x 16) + (1 x 4) = 20 (base 10)

Write the following numbers in binary (base 2)

21- 10101

24- 11000

30- 11110

Q6) What is a byte?
A Byte is 8 bits.

Q7) How many bytes in a kilo, mega, giga and tera bytes?

Kilo- 1024
Mega- 1,048,576
Giga- 1,073,741,824
Tera- 1,099,511,627,776

Mini Project..

I think I've got enough information, but it's hard to find some for legal responsibilites of those maintaining the database..

Mini Project: Social Issues related to databases

The people in our group are Reshma, Kirsten and me.
The social issue that we're going to research is "Identity Fraud".
I'll be doing questions:

4. Describe some of the ways in which this data can be misused.
6. What are the legal responsibilities of those maintaining the database?

Creating a form

In this activity, I created a form based on the 'data types' database that I made in the previous activity.

A form displays one record at a time, which is easier to read.

I clicked on 'Create form by using wizard' and on the form wizard,

I can choose which fields that can be shown in the form, I chose 'Field Name', 'Data Type' and 'Description'.

This picture shows how I wanted to display the information in the form.

I just chose 'Columnar'.

This is what the form looks like.

It's a more convenient way of displaying information as opposed to a table,

as each record is displayed one at a time, so it's more easier to read the record that you are looking for.

The problem with this type of form is that if you're looking for one record and there's around 500 records, you would have to look at each record individually until you find the one that you're looking for

Data Types

In this activity, we are to create a record of each of the data types that are available in Microsoft Access.

Querying A Database

In this activity, we are required to make queries which is basically searching for information in the databases that we have made in the previous activity.

We had to open up Microsoft Office Access
and under the 'Objects' column, click on 'queries' and click on 'Create Query in Design View'.

Q) 7&8

By dragging the Surname, First name and Postcode on the 'Field' rows, the program will know which field that we want to search in.

As shown in the picture, the numbers 2145 is typed into the Criteria row and This means that we are querying/searching for people in the address book that lives in the postcode 2145.

Q) 9-11

By clicking on 'save' and then 'open', you can see that the people listed are those in the database with the postcode of 2145.


Q) 12

This time, the number 2766 was typed in the 'or' row.

These are the results for the query.
The information that the second query selected are those with the postcode 2766.
Therefore, my results display the people who live 2154 OR 2766.
(I use microsoft office 2007 at home)


Q13)

In the 'criteria' row, I typed in *2 which searches for phone numbers ending with 2.


I also typed in *3* which searches for phone numbers with a 3 in it.

The query *2 didn't come up with any results,
so I just included the results of the *3* query.

Q) 14
A- Postcode of 2145 or 2146


Results:



B- Postcode between 2145 and 2146

Results:



C- Surnames starting with S


Results:



D- Surnames or first names containing M


Results:



E- Surnames and first names containing A


Results:

Creating a Basic Database... address book

We were required to create a basic database using Microsoft Access 2003 using the fields

Surname, First Name, Date of Birth, Home phone, Mobile, Postcode, Street and Suburb.

The instructions said to add around 10 people, but I didn't have 10 people to add right now.

I scribbled out the streets and phone numbers for privacy purposes.

Database Definitions

A list of definitions from Webopedia.

Field- A space allocated for a particular item of information. In database management systems, a field can be required, optional, or calculated. A required field is one in which you must enter data, while an optional field is one you may leave blank. A calculated field is one whose value is derived from some formula involving other fields. You do not enter data into a calculated field; the system automatically determines the correct value.

Record- A collection of fields is called a record. In database management systems, it is a complete set of information. Records are composed of fields, each of which contains one item of information. A set of records constitutes a file. For example, a personnel file might contain records that have three fields: a name field, an address field, and a phone number field

File- A collection of data or information that has a name, called the filename. Almost all information stored in a computer must be in a file. There are many different types of files: data files, text files , program files, directory files, and so on. Different types of files store different types of information. For example, program files store programs, whereas text files store text.

Query- A request for information from a database.

Database- A collection of information organized in such a way that a computer program can quickly select desired pieces of data. You can think of a database as an electronic filing system.

Report- A formatted and organized presentation of data. Most database management systems include a report writer that enables you to design and generate reports

DBMS(Database Management System)- A collection of programs that enables you to store, modify, and extract information from a database. There are many different types of DBMSs, ranging from small systems that run on personal computers to huge systems that run on mainframes.

Data Dictionary- In database management systems, a file that defines the basic organization of a database. A data dictionary contains a list of all files in the database, the number of records in each file, and the names and types of each field. Most database management systems keep the data dictionary hidden from users to prevent them from accidentally destroying its contents.
Data dictionaries do not contain any actual data from the database, only bookkeeping information for managing it. Without a data dictionary, however, a database management system cannot access data from the database.

Data Type- Classification of a particular type of information. It is easy for humans to distinguish between different types of data. We can usually tell at a glance whether a number is a percentage, a time, or an amount of money. We do this through special symbols -- %, :, and $ -- that indicate the data's type. Similarly, a computer uses special internal codes to keep track of the different types of data it processes.

Database Activity: The Yellow Pages

Definition of Database:

A database is a structured collection of records or data.
It is a collection of information categorized by specific fields and are usually searchable by keywords. A computer database relies upon software to organize the storage of data.

Examples of databases:
-Yellow Pages
-White Pages
-Wikipedia
-Address book


1) Bennett Office Supplies
122 Katoomba Street, Kattomba NSW 2780
ph: (02) 4782 2228
2) M & A Fresh Cut Flowers
91a Folwer Road, Merrylands NSW 2160
(02) 9892 1564
3) Go to Yellowpages and look up "motels" and type in "Noosa, QLD" in the location bar.



- Is the yellow/white pages a database? Give reasons for your answer.
The yellow/white pages is a database because it has a collection of data containing relevant information of businesses and is categorized by specific fields.
-What can you see as some of the advantages of using this electronic database compared to the conventional paper based version of the yellow pages?

• Easier and quicker to search for a business that you are looking for.
• Updates more often compared to the paper based version.
• Saves time rather than flicking through pages to search for a business.

-Do you see any dangers or disadvantages in this online version of the yellow pages?

• Can be hard to use for people who are computer illiterate
• Sometimes, the most relevant information are towards the bottom of the list.