DevelopmentEvaluation Solution Requirements Solution Constraints Evaluation Criteria Manipulation...

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IT EXAM REVISION 2012

PROBLEM SOLVING METHODOLOGY

PROBLEM SOLVING METHODOLOGY

Development

Evaluation

SolutionRequirementsSolution Constraints

Evaluation Criteria

Manipulation

Scope of solution

Solution Design

Testing

Documentation

Validation

Strategy

Report

DesignAnalysis

Fill in the correct activities under each stage

11 Activities

4 Stages

PROBLEM SOLVING METHODOLOGY

IT THEORY

DATA & INFORMATION

Information is refined, organized and value added facts, figures or ideas.

Ages of My Yr 11 Class

0

2

4

6

8

10

12

15 16 17 18

Age

Fre

qu

ency

Data is unprocessed, unorganized and discrete facts, figures or ideas. Eg 16, 17, 16, 16, 16, 17, 17, 17, 16Quantitative: in number formQualitative: in a “quality”

PRIMARY & SECONDARY DATA SOURCES

Primary source data: facts obtained through measurement, data collection forms, interviews, direct observation or by electronic mail.

Secondary source data: gathered from the published work of someone else eg books, newspapers, magazines, online databases, the Internet, etc

QUALITATIVE & QUANTITATIVE DATA

Quantitative data is measurable and specific and therefore easier to chart or graph.It is usually gathered through surveys, questionnaires and observation.Eg Fifty percent of market attendees bought a product from the market.

Qualitative data is harder to measure.Use interviews, video footage and observation to gather the data.Rich descriptions to find themes.Eg on a cold and wet winter’s day, many older members of the community turned up to the market dressed in raincoats, scarfs and carrying umbrellas

COMPONENTS OF AN INFORMATION SYSTEM

People

Procedures: Who does What

and When?Equipment: Hardware and Software (incl.OS)

Data

An Information System is people using

computer equipment to process data following certain

procedures.

EFFICIENCY AND EFFECTIVENESS

Efficiency: A measure of how little time, cost and/or effort in order to achieve intended results

Effectiveness: A measure of how well something works; the extent to which it achieves its intended results Remember: CARATACCRU

(Completeness, Accuracy, Relevance, Attractiveness, Timeliness, Accessibility, Communication, Clarity, Readability, Usability)

NB: Do not use either of these words in any IT exam without explaining them in the same sentence.

INFORMATION PROCESSING STAGES

Acquisition Input Validation Manipulation Storage (incl. Backups) Retrieval Output Communication Disposal (incl. archive)

CHARACTERISTICS OF AUDIENCE Age Gender Special Need Culture Education Status Location

PURPOSES OF INFORMATION

Inform Persuade Educate Entertain

DESIGN ELEMENTS

Appearance• proportion (visual hierarchy) • orientation (direction/ aspect) • clarity and consistency• colour and contrast

Vertical

Functionality structure usability and accessibility, incl.

navigation and load time appropriateness and relevance

Format: the style or layout Eg chart, table,

columns, etc. Convention: a commonly understood and agreed way of

doing something Eg. text aligned to left, numbers aligned to

right Graphs and charts have titles, legends

where necessary, labeled X and Y axes. Not to many fonts, sizes and styles Don’t put red and green together Light backgrounds, dark text Heading size is large and bold $, %, kg, etc in heading and centred.

FORMATS AND CONVENTIONS

WEB AUTHORING

DESIGN TOOLS (WEBSITES) Methods for representing

the functionality and appearance of solutions.

Sitemaps Annotated

diagrams/mockups Layout diagrams Storyboards

PROJECT MANAGEMENT

PROJECT MANAGEMENT

Planning, organizing and monitoring a project (POM)

Gantt charts Milestones: the end of a group of tasks, completion

point in a project, zero duration Dependencies/predecessor: a task that must be

completed before another task can begin Project managers needed to manage time, people,

all resources Critical path is the longest path and if takes longer,

the whole project takes longer. Project schedule (table) shows tasks, start and

finish dates

GANTT CHART

Graphical representation of the project Timeline that shows when tasks start and

finish and what resources will be needed at each stage.

Looks like a bar chart where each bar represents a task and the longer the bar, the longer the task.

Cleary shows dependencies and order

SPREADSHEETS

SPREADSHEETS

Workbook Worksheet Rows and columns Cells (intersection of row and column

(eg C12)) Design tools include layout diagrams,

IPO charts, flowcharts,

SPREADSHEETS

Formulae (SUM, average, max, min, count) Conditional statements (if, countif, sumif) Lookup tables Absolute and relative values ($A$2 vs A2 ) Fill down and across Charts Sorts and filters

VALIDATION

Manual validation Proof reading

Electronic validation Conditional formatting Range checks =IF(A1>0,”Continue”,”Stop”) Existence checks =IF(ISBLANK(A1), “Enter a

number”, “Continue” Data type check =IF(ISNUMBER(A1), “continue”,

“Enter a number” Limited list, predetermined list of options

NETWORKS

WHAT IS A NETWORK?

A network is two or more computers connected together.

A network connects computers together so that they can share data, information and resources.

Resource sharing (Internet access, printers, servers, modems, scanners, software)

Facilitating communication (improves communication, simpler , easier and faster communication, email, chat rooms, messaging, telephony, video conferencing)

Remote services (for customers or B2B eg on-line ordering, ATMs, EFT, etc.

Data and information sharing (prompt access to accurate information, synchronizing the data, reduction in data duplication )

Also cost savings, network management, improvements in efficiency and effectiveness.

ADVANTAGES OF NETWORKS

Limited geographic area Each computer or device called a node Cables or wireless Eg within an office building, university,

school or home Wireless LAN (WLAN) uses radio

waves, satellite communication, microwave or infra-red media to transmit signals between nodes.

LOCAL AREA NETWORK (LAN)

Large geographic coverage Communication is carried by a medium

owned by someone else. Transmission media can include

microwave, fibre-optic cable, telephone lines and satellites

A metropolitan area network (single city) Statewide network (entire state) National are network A worldwide network (eg Internet)

WIDE AREA NETWORK (WAN)

NETWORK INTERFACE CONTROLLER/CARD NICs provide a physical connection from a

computer (or node) to the network Sits in expansion slot or built into

motherboard Coordinates the transmission and receipt

of data, instructions and information to and from the computer

Each has a unique 48-bit MAC address Stored in ROM Media Access Control Acts like a name for the card No two the same

Controls traffic on the network and defines how devices will communicate with each other

Controls file access, manages print queues, tracks users, authenticates access, maintains log of network use and problems

Network client software installed on each workstation

MS Windows Vista, Windows 7 and Windows Server 2008; Novell and Apple

NETWORK OPERATING SYSTEM

Modulate/ Demodulate Dial up modem Two different types of broadband

Internet: Cable modems receive their Internet

signal through a cable line DSL modems receive their Internet

signal through a standard phone line.

MODEMS

Provides access to the Internet for a fee Speed of connection (dial up, cable or DSL,

satellite) Price $ Download and upload speeds for each

connection type NB: The faster the Internet connection, the

more you are going to pay for it. Terms of the contract Customer service Reputation

INTERNET SERVICE PROVIDERS (ISP)

A service provided by large Internet-based specialised data centres that offer storage processing and computer resources.

Advantages: Reduced hardware costs Faster updates and maintenance Save on energy bills Costs associated with amount of use Disadvantages Security is only as good as security in cloud Requires stable internet connection Information is backed up forever May need redundant Internet connections Privacy is an issue

CLOUD COMPUTING

PROGRAMMING

PROGRAMMING VS SCRIPTING LANGUAGES

Programming language is a method of communicating instructions to a computer. It has more features that can be programmed as they are not restricted to on application environment (eg VB.net, C++, etc)

Scripting language is a programming language designed to program within an application (eg ActionScript for Flash, JavaScript for web pages)

PROGRAMMING TERMINOLOGY

Objects: text boxes, buttons, labels, images

Properties: features of objects eg name, colour, text, visible, etc

Variable: temporary storage location for data

FILE MANAGEMENT

Hungarian notation: btnExit frmOrder lblName txtGuessFile names: Meaningful Consistent Easily

identifiable

File extensions: MS Excel = .xlsx MS Word = .docx MS Access = .accd Visual Basic = .vbx Adobe Photoshop

= .psp Text file = .txt Comma separated value

file = .csv