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					Hamilton Grammar School ICT Department Learning Criteria & Self Evaluation 2007-2008 Standard Grade

Student Name: __________________________
Complete the smiley or colour it in - for each bit of information in this book (but only for the pages you are told to read)

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I know exactly what this means and can explain it

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I know what this means but I find it hard to explain

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I don’t know at all what this means Help Me Please!

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The following list is only a quick guide to what you need to know ( All these topics are in your Walsh book – mind and use it!) Computer Systems

Hardware Software

The physical parts of the computer The programs(instructions) & data used by the computer. A program that works and links all the part of the computer functions (it is software)

Operating System

The tasks the operating system has to do are; Provides the HCI Manage the files on the storage devices Manage the computers memory Report errors to the user Schedule the tasks Organises input and output

There are two types of files Program files – Data files -

files that you can run – i.e a word processor etc files that are used by the program files

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Directory/Folder

two names for the same thing – files are stored in these to keep them organised and available

Filing Systems

Files are stored on the backing store. There are two main ways of storing this data; Flat filing - all files are stored in a single directory/folder, Each file must have a unique name No security

Hierarchical - files grouped in folders Files can have the same name if they are in different folders More secure Like files are grouped together

Operating systems can be realtime or interactive or background Realtime - this type of processing responds instantly to any data entered. Used in systems where you can not wait. Interactive - this type of processing will carry out your instruction as soon as it can. It might finish its current job first. Background job - this is when a job is done without interaction with the user i.e. printing when you are using the word processor .

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Computer Memory and Backing Storage capacity as follows

Bit = binary digit (an individual 1 or 0) Byte = 8 bits Kilobyte = 1024 bytes Megabyte= 1024 kilobytes Gigabyte = 1024 Megabytes Terabyte = 1024 Gigabytes

Backup

A backup is a copy of your files they should be made to a portable storage media, regularly and stored in a safe place away from your computer.

Backing storage devices that let you go directly to your data are called random/direct access devices - most backing store devices are now Random/Direct Access devices Backing storage devices that make you go through all your data until you get to the correct data is called a Sequential Access device - the only one still in use is Magnetic Tape Types of backing store. Magnetic Floppy disk (1.44Mb) Hard Disk(20 Gb – 160Gb) not portable Zip Drive (250 - 650Mb) USB Flash Memory (32Mb – 1Gb)

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Optical CD-ROM/CD-R/CD-RW(650Mb) DVDROM/DVDR/DVDRW(4.7Gb) Backing Store is used for the long term storage of data

Two main types of memory are RAM (Random Access Memory – can be changed - volatile) ROM (Read Only Memory - data can only be put on it at the time of manufacture) CPU – Central Processing Unit – does all the data processing done in the computer The three parts are ALU - Arithmetic Logic Unit ( does all arithmetic tasks and also all logic tasks like AND and OR. CU – Control Unit (supervises and controls the information between the processor and memory). Registers - storage locations in the CPU used to hold data being processed. Computer Word The amount of data that can be processed in one go. An 8 bit computer can only processes 8 bits. A 32 bit computer can process 32 bits in a single go. each location in the computer memory has a unique address – that‟s how programs don‟t get put on top of each other in memory.

Addressability

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Standard data types are used to make it easy to move data between applications and types of computers i.e doc, rtf, jpg, tif Text coded using ASCII (American Standard Code of Information Interchange) This is the range of character that your computers ASCII code represents - the main letters are the same everywhere but some character can vary depending on the country £ -# ASCII characters that are used to format (control) your text but don’t print out - the SPACE, TAB, RETURN Each part of the picture is called a pixel (picture element). Resolution is the number of pixels that are used to make up a picture - the more pixels per inch the greater the resolution (quality ) – measured in DPI(dots per inch).

Character Set

Control Character

Graphics

Operations you can do with graphics Move Resize Rotate Flip Cut

Copy

Paste Crop Scan

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To calculate the size of a black and white bit-mapped graphic takes up in memory do the following; 8 pixels 1 0 0 0 1 0 0 1 0 0 1 1 0 0 1 1 1 1 0 0 1 0 0 0

0 0 0 0 0 0 1 1

0 0 0 1 1 1 1 0

0 1 1 1 0 1 0 0

0 0 0 0 0 0 1 1

0 0 0 0 0 0 0 0

8 pixels 64 pixels = 64bits 64bits divided by 8 = 8bytes

Steps 1. Calculate the number of pixels (no. across X no. down) 2. That number is the total number of bits 3. Now change it to bytes (divide by 8) 4. If the number of bytes is greater than 1024 divide by 1024 to change it to kilobytes (If still greater than 1024Kb the divide by 1024 again to get Mb) Know the main Input Devices (and their properties and what they are used for)

Keyboard Mouse Trackball Scanner

Touch-sensitive screen Light – pen Graphic tablet Voice recognition Handwriting recognition

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Know the main Output Devices (their properties and what they are used for) Laser printer Inkjet printer Dot – matrix printer Plotter Monitor LCD screen (TFT) Loudspeaker (earphone)

Specialised input/output devices for VIRTUAL REALITY – (an artificial world) Head set (contain goggles,speakers, sensors – to sense movement)

Data gloves include sensors to sense movement (a similar device for the whole body - data suit)

Mainframe computer A very large powerful computer that allows multi-user and multi programming uses terminals(monitors and keyboards) Standalone computer A computer that is not connected to any other or part of a network Network A network is two or more computers joined together

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
LAN – Local Area Network Permanently joined (hard wired or wireless) Share hardware Share files Communication Reduce cost for peripherals and software Small geographic area Very fast and reliable WAN – Wide Area Network Joined by phone /cable lines - use a modem Used to share programs and data Can cover the whole World Communication Not as fast as LAN or as reliable A MODEM is a hardware device used to allow a computer to use a telephone line to connect to a WAN. The modem changes the Analogue signal of the phone line to the digital signal of the computer and vice versa.(Modulator/Demodulator). Speeds - slow using phone lines many times faster using broadband Security Physical - Keep system secure (lock the door) Use passwords Use encryption Different levels of access more than one user can access the system at the same time.

Multi –access

Client and server network Computers (clients) in the network share the hardware/ info from a more powerful server computer Printer server - a printer used by the whole network File server – a hard disk used by the whole network

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
All printers (and other peripherals) work differently – they require their own program to make them work properly – this is called a driver.

General Purpose Packages
Types of applications Word Processing Database Graphics Presentation Integrated packages Spreadsheet Communications DTP

a single program that contains the features of two or more GPP‟s cost Common HCI Data compatibility Reduced functions on applications May included applications not wanted the method by which the user and the computer communicate.

Reasons for

Reasons against

Human Computer Interface (HCI)

You need to know about a WIMP HCI - Windows Icons Menu Pointer WIMP systems and applications are easier to use because they; Are intuitive to use Have On-line help Have on-line tutorials Use icons to represent programs Files/folders Hardware

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
(sometimes also known as GUI‟s Graphical User Interface) The HCI can be made more user-friendly by Using Icons, Online help, Customising

Features Common to all GPP’s NEW CLOSE PRINT MOVE OPEN SAVE COPY FORMAT data

headers footers top/bottom/left/right margins ruler Linking Data inside and between documents Dynamic Data Linkages Data is linked to another part of a document, eg a chart, and when the data is changed the chart is automatically changed. Static Data Linkages Data is linked to another part of a document but after the link does not update when data changes. This is a one time link.

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Freeware - any program that you can use without paying Shareware – you can install this software free for a trial period but are then expected to pay for using it

Features of a Word Processor Wordwrap when a word does not fit on a line it is moved to the next line. The word may be hyphenated. lines up text with tab marks on rulers

Tab

Spellcheck

compares words entered with own dictionary –if not found then suggest alternatives Any word not in dictionary i.e names will show up as mistakes Words with different spelling do not show as errors. Two, to, too text is formatted in a particular way i.e. left aligned/justified right aligned/justified centre aligned/justified fully aligned / justified function to search for a particular word and replace it with another
(always mentioned the words to be searched for and their replacement)

Justification/Alignment

Search & Replace

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Formatting Text style – font bold size underline italics

Document Template

A master copy that is used to get a copy of the layout and format for a new document every time you use the template. a saved paragraph that can be loaded into as many different documents as required a letter that is loaded when needed that has only the personalised details to be entered.

Standard Paragraph

Standard Letter

Mail Merge Use a Standard letter and a source of data to produce personalised copies of the standard letter. eg. Insert data from a spreadsheet or database (data source) into a standard letter to produce personalised letters/bills or other documents

Steps to create merged letters 1. Create or load standard letter 2. Create load data source 3. Insert field names from data source 4. Merge to a new document 5. Save and print

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Spreadsheets A spreadsheet is like a grid of boxes Each box is called a cell A line of cells horizontally is a Row A line of cells vertically is called a Column There are three types of data Numerical data (Values) Text (Alphanumeric) Formula that use other cells or functions to do calculations or operations Functions (All functions start with “=”) =SUM(A1:A6) adds all numbers in cells A1 to Cell A6 inclusive averages all numbers in cells A1 to Cell A6 inclusive Gives you the largest number in cell range A1 to A6 Gives you the smallest number in cell range A1 to A6

=AVERAGE(A1:A6)

=MAX((A1:A6)

=MIN(A1:A6)

=IF(A3>20,”pass”,”fail”) If the contents of cell A3 is bigger than 20 then show the word „pass‟ else show the word „fail‟

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Sweets
25 20 15 Series1 10 5 0 mars twix crunchie

Charts

are used to display information , a clear way to display numerical data. Cell attributes are the properties of individual cells. I.e currency, date, alignment, font colour, size(width, height), protection.

Cell attributes

Cell protection

This stops data and formulae being changed. Either on purpose or accidently.First enter all formulae and data you want locked then select from format only those cells you want to protect and set to locked. Now go to tools and protect the sheet. Replication (copying) Replication is an easy way for us to get formulae into cells when the formula only changes because of its position in the spreadsheet. This means we do not have to enter it into individual cells. This saves time and reduces errors. Relative reference When a formula is copied the relative parts of the formula are automatically changed so that it is relative to the position in the spreadsheet it has been copied to.

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Absolute the cell reference in a formula is locked with the $ sign that part of the reference will never change.

The „$‟ sign is used to show which part of the cell reference is Absolute and will not change when replicated.

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Databases Data is the ‘information’ that is processed by the computer it only becomes information when we know what means. i.e ASCII code 65 = “A”

A database is a collection of organised information. It can be manual or computer based. Databases can be shown either as a record view or as a list(table) view Record View(form view) Name : Date of birth Gender Age : Fred Bloggs 22/11/90 Male 13

List or table view Name Fred Bloggs Snow White Mickey Mouse DoB 22/11/90 24/09/91 13/05/89 Gender Male Female Male Age 13 12 14

All this information is collectively called a file. All the information about one person or object is called record. Each type of information is called a field. (common fields types text, integer, floating point, graphic, date, time) The field used to find specific information is known as a key field. (manual databases i.e phonebook can only have one.)

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Databases are used to do two main tasks sorting and searching. Sorting : on one field Q. Show the pupils in order of age Ans “I would Sort on field age in ascending order” Sorting : using two fields Q. Show pupils group by registration class in alphabetical order Ans “I would Sort by field registration ascending and by field name ascending”

Searching : on one field is called a simple search Question Display all students who are 13 yrs or younger Answer. I would do a Search (Filter) on field age <= 13 Alternatively Search (Filter) on field age < 14

Searching : using more than one field is called a complex search. Question. Print all the boys in the database who are less than 14 years old. Answer I would do a complex search using field gender = “male” and field age < 14 and print out the list

In this example the field age would be a computed (calculated) field. It is not entered by the user but automatically calculated using the current date and the entry in the persons date of birth field – your age changes your date of birth does not. You should know about the purpose of: The Data Protection Act The Computer Misuse Act The Design , Copyright and Patents Act Calculate the size of a database.

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Hamilton youth club have a database to hold details of all their members. They have 156 members on their roll. Calculate the size of one record and the total size of the database. Calculate the size of one record Show all working - you get marks for each part Name : Date of birth Gender Age : Fred Bloggs 22/11/90 Male 13 The name field is 45 bytes The DoB field is 12 bytes The gender field is 6 bytes The age field = 1 byte 64 bytes 45 bytes 12 byes 6 bytes 1 byte

Total Record Size

Calculating The size of a database First work out the size of each record (see above - ) = Size of each record X number of records = 64 X 156 = 9984bytes change to kilobytes = 9984/1024 = 9.75Kb Multi – Media Presentation software and web pages can contain Multi - Media To have multi media you have to include other media apart from text and still images. I.e add sound, animation, movies. Size of database

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Programming A program is a list of instructions All programs have to translated into machine code before they run. Machine code is a low level language that the computer can understand. Methods of translation Interpreter Each line of high level language is translated into machine code every time it is used and then its instruction carried out. Usually slower than Compiled translators Easier to debug (correct errors) as the program stops at the actual error. Compiler The whole program is entered in a high level language, this file is called the Source Code. A program called a Compiler then creates a machine code version called the Object Code. It is this version that users see. Usually runs very fast It can be difficult to find mistakes. High level languages = Visual Basic, C, Pascal, Cobol, Fortran, have certain common features: English like words Designed for humans to use Portable (can be run on different types of processor) They have to be translated into Machine Code before they can run. Many programmers save parts of programs that they have tested and used before, they store them in a Program Library.

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Presentation & MultiMedia Presentation software and web pages can contain MultiMedia To be multimedia you have to include other media apart from text and still images. I.e add sound, animation, movies. A wizard is a program to guide you through a particular task Internet www world wide web (lots of web pages joined together over a wide area network)

hyperlink a link on a web page (or other programs that take you directly to another web page) hotspot an invisible area on a web page that makes another process run (i.e. your pointer changes shape) Hyper Text Markup Language the language used by the internet

HTML

Expert Systems Is a program that produces the same results as a human expert Advantages Available 24/7 No human expert required Can have as many copies as you like Disadavantages Expensive to create Do not use common sense

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Commercial Data Processing Reason databases used in business and government are too big for desktop and laptop computer. They need to access information very quickly, and by large numbers of people at the same time. Only a mainframe computer is large enough to cope. They have to be Multi Access (many people on the same computer at the same time) They use Dumb terminals (they only have a keyboard, mouse and monitor, no CPU or memory or backing store) Data Processing Cycle

Data collecting & Preparation

Data Output

Data Input

Data Storage & Processing

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation
Data collection and Preparation has to be done as fast and as accurate as possible. Ways to do this is by using: Bar Codes Mark sense Cards Magnetic Strip

EFT Electronic Fund Transfer - money is moved about electronically you an pay for goods over the internet, or by phone. 24/7 access no delay your account is updated very quickly POS Point Of Sale - Computerised terminal in a shop (a till). No money needs to be carried. Use a credit or debit card. EFTPOS - a computerised till a shop that you can pay for goods electronically using a credit or debit card Smart Card - Either a credit or debit card that has its own processor holding lots of data (Chip & PIN) Fraud is much more difficult to carry out since the Chip & PIN (Personal Identification Number) you need to know the correct number for the card.

Verification Check the information is entered correctly, by entering it twice (Changing your password) Validation checking information is sensible, this check is carried as part of a program. ( i.e a range check)

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Hamilton Grammar School
ICT Department Standard Grade

Learning Criteria & Self Evaluation Date Pages Checked Action initial

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