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9691/01 Computing
SYSTEMS DEVELOPMENT LIFE CYCLE
THE SYSTEM DEVELOPMENT LIFE CYCLE, PROBLEM DEFINITION;
Problem Specification
Existing problems identified
User requirements
As outlined by the warehouse
FEASIBILITY STUDY;
Technically feasible
o Whether or not the proposition is practical
o System may require hardware that is unavailable Economically feasible
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o Establishing whether it is cost effective o Only feasible if the benefits outweigh the costs
Socially feasible o How will the users react with a new system?o Change of job or loss of jobs
Time feasible o Time required for new system to be readyo Can the system be ready for a given time scale?
Legally feasible o Is it the proposed system in conflict with any legal requirementso Meeting the requirements of data protection legislation
ANALYSIS;
Analysis
Production of a requirements specification
Detailing inputs needed and outputs required
Specify user requirements
Hardware/software needs
Fact finding (questionnaire/interview/record inspection/observation etc)
Areas of the current system contained in the system analysis report
Types of data
Sources of data
Data maybe a certain type such as numeric/test/graphics/sound, etc
Flow of information arou8nd the current activities/processes, etc
Data capture methods, investigating the types of source documents currently user
Users involved, identifying their requirements/abilities
Types of processing/processes used, describing what happens to the inputted data/checking
procedures
Storage methods, and how the stored data is accessed
Types of output required from the existing processes
Volume of data to be input/processed/output/sotred
Problem Identification/Specification
Existing problems identified
User requirements
As outlined by the warehouse
Methods of Fact Finding
ObservationAdvantage
o Allows the analyst to see a current process at first hand o Analyst can get a feel of user competence and abilities in doing a task o Analyst can get idea of time required to do a task, constraints and strengths of
current system
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o Does not require employee to leave their jobDisadvantage
o Users may respond differently if they are being observedo Lack of interaction between analyst and use
Interview(s)Advantage
o User can express their opinions in a detailed wayo More factors may come to light as the user answers questions
o Questions can be modified according to answers given
o User may feel valued by the personal nature of interview
o Analyst and user can build up a working relationship
Disadvantage o Time consuming for analyst to gather factso Users may not tell the truth if they feel intimidatedo Suggest answers the analyst may want!
QuestionnairesAdvantage
o A lot of data can be collected in a short period of timeo Efficient in terms of time
o Useful when a little information is required
o Not difficult to complete
o Direct data entry/OMR/can be distributed electronically
Disadvantage o Difficult to designo Inflexible opportunities to respondo Low return rate from staff
Record/document inspectionAdvantage
o Analyst can get an idea of the volume of data storedo See how data is collected/stored
o Can inspect how data is verified/validated
o See how data is processed
Disadvantage o Limited interaction with potential userso Time consuming..o
. if there is a large volume of files Group Meetings/Interviews/Discussions
Advantage o Quicker than individual interviewso .as you can get group opinions/wide variety of thoughts
o True picture of whats actually happening
o . which may not be the same as how management are thinking
Disadvantage o Individuals may not contributeo A wide variety of thoughts making it difficult to establish user needs
Data flow diagram
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Source of the data
External entities [1]
Data processes
Data flows in/out of processes
Data stores
System flow chart
Processes/activities to be carried out
File storage (or media)
Input/Output
Files to be used (Master/transaction/backup)
DESIGN;
Design
Specification of system
User Interface designed
Specification of data structures
Prototyping
Algorithms
Files/file structure
Input/form design
Output/report design
Validation procedures
Security of data
Tasks at the design stage
Designing data collection forms/data capture technique
To cope with volume of data/considering the type of data to be collected
Design of validation techniques/verification of data
To assist in avoiding/handling input errors/to ensure data is correctly entered or processed
Design of input/output formats
Including screen layouts/report layouts/data collection Including user interfaces and screen layout
User interface and screen layouts
Description of interface (GUI, Menu, Command)
Design of a test plan/test strategy
To test the parts/all of the system/meeting the objectives of the new system
Choosing a software/hardware solution
With reasons for selection
Conversion/implementation plan
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Data structures/data file/relationships
Need to carry out file sizing
to ensure that the hardware and communication
strategies can cope with the volume of data
DEVELOPMENT ;
Coding /software development
Production of programs
Tailoring software
Modification of code
Production of documentation
IMPLEMENTATION AND TESTING;
Implementation/conversion
Method of conversion/changeover (parallel, pilot, direct, etc)
Staff training
Master file set-up (setting up data/transferring date)
Installation of hardware Installation of software
Changeover
Direct changeover/Big Bang
o Old system stops and the new system begins
o No overlap between systems/no part changeover
o Advantage: Staffing costs are kept to a minimum as only one system has to be
supported
o Disadvantage: If new system fails old system cannot be used
Parallel changeovero Two systems run side by side for a period of time
o Advantage
Comparing results of two systems can happen
If new system fails, old system can be used
o Disadvantage
Staffing implications (as data has to be input to two systems at the same
time)
Additional costs with two systems doing the same task
Pilot changeover
o New system could be used in a few areas initially
o The results could be compared against the other areas that use old system
o Roll out the new system if successful/abandon the new system if unsuccessful
To changeover the old system to the new system/to convert existing data to new system
Method of processing to be used
Justifying the method
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Phased changeover / gradual changeover o Each part of the existing system is changed over separatelyo Each part can be tested separately o May take a long time for the whole system to be changed over
Testing
Production and the carrying out of a suitable testing strategy
Production of test data
Alpha/beta testing
Different types of testingextreme, normal, exceptional
Specify expected results
The role of the enduser in the testing stage
Acceptance testing
Endusers are using the software on a day to day basis with realistic
volumes of actual data
Ensure the system meets their needs/requirements
Report faults/errors back to analyst
Suggests changes/modifications to the system
Tests with real data
Reasonable response time
Easier to use than the old system
User interface is clear
Output as expected
Security is appropriate
Beta Testing
End user is an expert on the requirements of the system
EVALUATION;
Criteria
Suitability/Does the system really provide a solution to the problem? /Does the system meet
the user requirements?/Does the new software integrate with the existing software?
Effectiveness/Does the system do what it is supposed to do? /Does the system suffer from
bugs? /Are the access times for data retrieval acceptable?/Is the hardware/software reliable?
Usability/Do the users find it easy to use the system? /Do the users require continuous
training?/Is the online help/tutorials useful?/Do they have quick access to information?/Do
users save time not having to carry out tedious/repetitive tasks?
Maintainability/Will it be easy to maintain? /any shortcomings to be modified?/adding new
modules?/online upgrades? [1]
Security of data/Is the data secure against unauthorised access? /Are the data/software
backups taking place?/Are users coping with passwords/user ids? [1]
DOCUMENTATION;
Sections of Documentation
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Description of input/output
Brief description of what the package does
Machine configuration
Hardware and software requirements
Operating instructions
Installation guide
Simple error messages/troubleshooting
Tutorials
Online help
Telephone help line / Contact [1]
Backup routines [1]
Contents/index [1]
Glossary [1]
Purposes of technical documentation
To allow debugging of programs.
To assist future software developments/upgrades.
To modify existing file/data structures.
To support new technical staff.
To allow software/new software to be installed
Online help guide
Tip of the day idea
The use of wizards/help assistants
Links to web sites
Builtin tutorials
Search using keyword on index
Direct e
mail to software provider FAQs
MAINTENANCE
Maintenance
Debugging the system
Modifications due to changing needs
Improving current processes
Corrective maintenance
Correcting errors in xxx system
Software is not performing tasks
Errors/bugs need to be removed from the software
Debugging
Adaptive maintenance
Changing needs of the xxx system
Identifying other user requirements
Changes in legal requirements/government policy
Changes in business practice
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Perfective maintenance
Software is performing task specified
But the system may be too slow in response times
Due to increase in volume of data
Improving performance
Review
Check against objectives stated
Any limitations
Any upgrades required
CHOOSING APPLICATIONS SOFTWARE
OFF-THE-SHELF AND CUSTOM WRITTEN SOFTWARE (PROS AND CONS);
Custom-written
Definition
o Software specially written for a particular user/organisation/Tailor made software
o meeting their exact requirements
o written in-house/outsourcing
Pros
o Designed to do exactly what the user needs/Fits user requirements exactly
o Programs can be written to run on existing hardware/comply with new hardware
purchased
o To integrate with existing software
o Minimal change to working procedures of organisation
o User support can be geared to meet user needs
o No excess functionality
o Sell copies to other similar users to recoup development costs
o Program maintenance may be easier
Off-the-shelf
Pros
o Readily available
o Third party user documentation availableo Shared development costs
o Tried and thoroughly tested
o Extremely reliable
o Third party training
o Compatibility with other users of the software
TYPES OF APPLICATIONS SOFTWARE
(e.g. stock control, order processing, payroll, process control, point of sale systems, marketing,
computer aided design (CAD), computer aided manufacture (CAM);
CAD
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Automatic 3D generation
o to show the different views of the shopping centre/walkthrough
Libraries of design objects / Templates
o to allow the architect to include pre-drawn parts of other buildings
Create/edit save
o to allow further manipulation of the design
Print or plot drawings
o to provide a hard copy for the builder/marketing
Placing pictures of existing buildings along side
o to see if they fit in terms of density and shape
Applying and calculating stresses and strains
o to the model of the building
Interface with specialised hardware such as scanners
o to allow a previous drawing to be input
Choosing materials to construct the design
o
of various parts of the building Choosing colours/patterns / Textures
o to develop different designs
Calculating amount of material required
o allowing for pricing of the shopping centre
Rotate/zoom features
o to manipulate the finer detail of the building
Direct link to CAM
o to realise/manufacture designs automatically
GENERIC APPLICATIONS SOFTWARE, THEIR PURPOSE AND IMPACT
(word processing, spreadsheets, desktop publishing; presentation, drawing)
Desktop publishing software/word processing software
Can produce high quality graphics and text
Can integrate text/graphics
Can use a newsletter template
Database software/Spreadsheet software
Can create a suitable record structure
Can query/add/delete/amend member details
E-mail/ Web authoring/messenger
To send e-mails to potential customers/ with website link
To create an interactive website
HANDLING OF DATA IN INFORMATION SYSTEMS
(inputs, validation and outputs)
DATA ENTRY, MANUAL AND AUTOMATIC
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(form design, keyboard entry, voice recognition, barcodes, optical mark recognition (OMR), optical
character recognition (OCR), data logging, touch screen);
Turnaround document
Document outputted by the computer.
Information is added and returned to the computer for further processing.
Does not need to be manually inputted.
Barcode
Characters are coded as a series of light and dark vertical bars of varying width
The bar code can be read by the handheld scanner or the laser scanner
The bar code reader uses laser beam light to enter the code automatically
Match bar code against stored database
Data is in numeric format
Builtin check digit used for validation
Uses include: Any application that identifies items such as: produce itemised bills/collect
data at POS terminal in shops or to track parcels in the post office or to track luggage in
airports or to issue books in libraries.
Voice Recognition
Data is input in audio form Directly through microphone Sound is digitised Indirectly through a tape
Software analyses sound inputted Matches against a library of sounds Match found, it is processed Else new sound generated, processed and stored Uses include Security systems/dictating text into a word processor, instructions to a robot, mobile telephone Advantage
o Natural way for humans to communicateo Minimal amount of training for user o User can use key words to trigger off whole statements
o People with disabilities can use this system o Hands free allows user s to do other activities
Touch Screen
User can make selections by touching the screen
They operate by means of crisscrossing beams of infrared light / wires
Embedded just in front of the glass
When the users finger touches the screen two sets of rays are blocked given an xaxis and a
yaxis point
Uses include banks, tourist offices, museums, information kiosks, Telephones/PDA,
restaurants etc
Optical Character Recognition (OCR)
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Enables the computer to identify by reflecting light onto written or printed
characters
Special recognition software is then used to turn each character into an ASCII value
Which can then be edited using a word processing package
The pattern of each character scanned is compared with already stored characters looking
for a match
Different font types and sizes are capable of recognition
Uses include: Application turnaround document in billing, scanning a hard copy into a word
processing or reading documents for the blind
Optical Mark Recognition (OMR)
It involves using a preprinted form
Including boxes in predefined areas
That can be shaded in by humans
And read/recognised by an OMR reader
Sensor Electronic component
Responds to a physical property such as temperature
Converts energy from one form to another
Data logging
Usemeasuring temperature, measuring humidity, magnetic tilt switches to movement
Magnetic Stripe Card
Data can be read from the stripe
By a magnetic stripe reader
The stripe can only store a small amount of data
The stripe consists of a thin layer of magnetic tape similar to that in a video/music tape
Use credit card/ bankcard/ loyalty card/membership card/ car/ hotel key
HOW IMAGES ARE INPUT
(scanners, video capture card, digital camera);
Scanner
Passes a beam of bright light over an image
Sensors are used to collect data about the amount of light reflected from different parts ofthe picture
This can separate the light intensities and the colour
This data is used to produce a digital image of the picture
This image can then be saved, and edited using image editing software
The resolution of the picture is determined by the file format, eg JPEG
Digital Camera
Pictures are taken by converting light passing through the lens of the camera
Grids of tiny light sensors can convert light to binary patterns
Each binary pattern represents a colour or shade of light The image captured will depend on the resolution
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Image taken is stored in the cameras memory/memory card
The image can be viewed immediately and stored or deleted
The image captured is in digital format
The contents of the cameras memory can be transferred to a PC for storing, editing, etc
Some digital cameras capture short video images
FREE TEXT AND STRUCTURED DATA;
?
DATA PREPARED OFF-LINE
See Batch Processing
VALIDATION AND VERIFICATION
Data Validation Definition
This involves checking data, done by the computer automatically at the input stage
Its purpose is to reject data that does not conform to certain rules
Reasonable and sensible
Validation methods
Length check
o Whereby the xxx number has a fixed number of digits
Format/picture/character type check
o Checking that all characters are of the correct type Presence/required field check
o Checking to ensure characters have been entered
(File) lookup/existence check
o Check that the code is that of an existing item on the system
Range check
o Checking that the data is within the preset limits
Verification
Process of checking data done manually (by humans)
It normally involves checking the data that appears on the screen with the data on the
source document
Visual verification
A method of double-entry can be used
Whereby two people enter the same data (double entry)
Results are cross-referenced to see if there are mistakes
Verification methods
Double-entry
o Data is entered twice by different operators and results compared
Visual/screen checking
o User reads the data on the screen to confirm it is correct
Check digit
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o Extra digit is added to a number and is used to check a calculation result
Batch total
o Total value of one or more fields in a batch of data/calculated manually and then
calculated by the computer for comparison
Control total whereby the batch total is meaningful
o Hash total whereby the batch total is meaningless
Check digit
Weights are applied to each digit in the code
Sum of the products is calculated
divide sum by 11 and the use remainder
11-R =Check digit
Special cases, such as R=1 check digit =X
WAYS OF OUTPUTTING
USER INTERFACE DESIGN
User Interface - Definition
Allows the human and the computer
to interact / communicate
Users can input/output data
THE IMPORTANCE OF GOOD INTERFACE DESIGN;
The considerations that contribute to good user interface design
Users the type of user/who is going to use the system and their computing
experience/backgrou8nd
Environment are the types of tasks to be performed such as is noise or safety a
consideration?
Hardware is the interface technically feasible or can it be designed using the existing
resources?
Consistency of layout of different interfaces
Volume of data on the screen at any one time
Legibility using appropriate fonts/colours, etc
Links between screens
Advantages to the user of having similar user interfaces
Common commands/the same keys/commands can be used on different Packages
Increased speed of learning
Once the user has been trained or has mastered a package the skills are transferable
Consistency in the content of toolbars and menus in different packages
Such as: Dialogue boxes, customisable features and operational features are similar
Confidence building among novice users
Layouts of screens and the positioning of items such as icons, menus and so on should be
consistent
CHOOSING APPROPRIATE HARDWARE FOR AN APPLICATION;
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HOW TO DESIGN THE HUMAN-COMPUTER INTERFACE;
Factors to consider
User Friendly/ease of use
o Meaningful iconso Well organised/uncluttered screen
o Common features with other packages
o Intuitive feel
o Colour contrast
o Type of font size
Help available for novices/inexperienced users
o Tutorials/demos
o Wizards
o Tips
o Concise, easy to read error messages
o Context sensitive help
Facilities for experienced users
o Providing short cuts users
o Customising menus
o Customising toolbars
o Function keys
Making use of human memory
o Making use of human long-term/short term memory
o Such as functions keys (f1 help)
o Recognisable icons
The type of usero May require voice recognition
o May require a touch screen
o May require certain large fonts/colours
o How the system helps overcome peoples fear
o Caters for disabled
TYPES OF INTERFACE AND THEIR CHARACTERISTICS ;
GUI Graphical User Interface
Windowo Screen is organised as a series of windows/overlapping frames
o That can be viewed singularly or in combinations
o Windows can be minimised/maximised/resized/moved
o Allows for multi-tasking
Icon
o Small graphical image
o To allow easy recognition (of applications)
o Can be pointed and clicked on
o Used as a short cut for the user/no need to type in commands
Menu
o Pop-up/pull down
o To select features/optionso From a predefined list of options
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o Used as an alternative to hot keys Highlighting Pointer
o To control the cursor on the screeno To allow the user to interact with the GUI
Dialogue box o To allow the user and the computer to interact in a controlled mannero To allow the computer to control what the user is doing
o By offering a limited number of choices o Such as yes/no/cancel[1] o with one choice normally set as a default value [1]
Wizards/templates[1] Scrolling [1] Help facility/tool tips
o User can enter key words/phraseso Package will provide guidance to carry out an activity
(Action) buttons[1] Toolbar
o Combination of buttonso Each button has an icon/letter o Depicting an option o Situated on the screen, the top, bottom, side or floating option
o Used in conjunction with a mouse
Form driven interface
An onscreen form looks similar to a hard copy version Similar layouts help transcription at the input stage They enable data to be entered in a predetermined and structured way User normally enters data into boxes provided which makes it easier for novice users Each text box is labelled with a field name List (or dropdown lists) boxes can be used to control what is entered Radio buttons and check boxes can be used to enter data If data types or data formats are not applied by the user automatic error dialogue boxes will
appear
Command line interface
Requires the user to learn a large number of commands
Use must key in commands
Idea of prompting the user for a command
It also requires the ability to join commands to form instructions
The syntax in the command line is critical / will not operate if typed incorrectly
Not easy to use for the inexperienced user
Experienced users who are familiar with all the commands would find this interface quite fast
compared to other types of interfaces Single commands can allow the user to perform powerful operations
Problems with speech recognition interfaces
Different kinds of voices (male/female) need to be understood
Different kinds of accents need to be understood
Background noise may distort students voice
Complex speech recognition software is required to understand different human voices
It takes a long time to setup/train such a system for each user
Multiple users on a computer
SPEED MISMATCH PROBLEMS
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EXTRA NOTES: TYPES OF INFORM ATION SYSTEMS
EXTRA NOTES: PASSIVE AND INTERACTIVE INFORMATION SYSTEMS;
Passive
Information cannot be changed
E.g. an encyclopaedia held on a CD
Interactive
Not only access the information but also change it
E.g. a shops database of products
MANAGEMENT INFORMATION SYSTEMS (MIS);
MIS - Definition
Piece of software which manipulates large quantities of data
To produce information
Which is useful for managers
Which helps in decision making
Desirable features
Ability to analyse data in many different ways and evaluate information
Increase of knowledge assists better decision making
Allows managers to avoid information overload spending more time with staff andcustomers
Be in a better position to plan for the future/understand the needs of customers
Use of probability to predict future trends
Factors that contribute to success
Training of managers/staff to use system properly
Information is produced in correct format
Information is targeted at different levels of managers
Data used is valid accurate
Data is useful, relevant, up to date, and on time It should be flexible, allowing different subsets of data to be extracted
Better decision making
Allows managers to avoid information overload
Better position to plan for the future
Better understanding the needs of customers
Limitations
If user needs are not fully identified, it can lead to problems
Lack of ICT skills among users/management can lead to under usage of MIS
May only be used for low level processing such as transaction processing
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Operational Level
o used for day to day decision making
o such as planning resources/manpower
o balance the tills at the end of each day
o
checking stock levelso daily information may be required
o such as best selling stock item(s) on given day(s)
Tactical Level
o Data is processed to allow for tactical decisions
o Used for short to medium term planning
o Such as need for moving stock from one area of a store to another
o Increase/decrease in item prices
o planning for staff training
o analysing weekly sales/profits
Strategic Level
o Used for long term planning
o by company directors
o To support What if decision making by management
o decision support
o Such as acquiring new stores
o ... selling existing stores
o what if the rent of a store increases
o predicting future turnovers
Usage in a hospital
Used for decision making
o At different levels operational, tactical, strategic
o Such as number of nurses required for patients (operational)
o Such as analysing the number of patients that were seen by a certain doctor over a
period of time (tactical)
o Such as future planning for medical operations/resources (strategic)
Used to protect from information overload
o Information is relevant/accurate/complete/reliable
o Information given in an appropriate format to the hospital managers
Used to controlling and monitoring
o Managers in the hospital can use a MIS to monitor of areas that are working
well/areas that are not
o Assist in remedial action for areas that need improvement
Used to co-ordinate/liaison
o To allow contact between different departments in the hospital
o Managers can co-ordinate the activities of various departments
BATCH PROCESSING AND RAPID RESPONSE APPLICATIONS (IN 9691/01 AND 9691/03)
(= real-time);
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Batch Processing
All data to be input is collected together
Stored as an offline transaction file [1]
before being processed [1]
In a single operation [1] Together as a batch
Processed at a convenient time
OffLine/Minimal human intervention
Reasons of Batch Processing
Similar data
Similar processing
Time of processing is not critical
No user intervention is required during processing
Batch Processing Tasks
Payroll for staff Producing statements for customers Updating standing orders/direct debits Adding/deleting interest payments to accounts Backup the database
Interactive/Transaction/Real time/Rapid response Processing
Provides the user with fast responses/Time delay in processing is insignificant to the user A transaction is processed before another one is accepted/Record locking occurs Online processing There is dialogue between user and computer [1] User able to alter data on the systems [1] System is updated before next transaction [1]
Reasons of Interactive Processing
xxx needs to be processed as quickly as possible Need to lock record Need to prevent double booking, etc.
Interactive Processing Tasks
Enquiries from customers Updating customer balances before making withdrawals at ATM/branch
Customers requesting a new cheque book/service/statement
Customers wishes to change their PIN
KNOWLEDGE BASED SYSTEMS (=EXPERT SYSTEMS) (DIAGNOSTIC, ADVICE GIVING
AND DECISION MAKING);
Expert System
An application of artificial intelligence
To a particular area
Where human expert knowledge and experiences
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Are made available through a computer package/software
It provides a user interface for doctors to input patient medical problems
An inference engine to search the knowledge base
A knowledge base containing facts/rules.
Or
Combines the knowledge of experts on a given subject
Using rules it has been given
Can make inferences/diagnosis
Benefit feature
Ability to diagnose a fault in the equipment
Suggest a recommended solution
Can combine the knowledge of many human experts
ability to retain the information
Much faster than a human at completing a task
Low error rate
Advice and recommendations are consistent
Provides probabilities of faults/ranks faults
Some systems can learn from mistakes [1]
Making the diagnosis more accurate
Ability to explain each part of the system [1]
Limitation
Difficult to capture all knowledge about components
From a wide range of human experts
Over reliance
Reduced dependence on the human expert
Do not learn from mistakes/new knowledge to be entered
Misinformed expert system can lead to errors
Parts of an expert system
User interface
To allow communication between the expert system and the real world
Building society can input application details
Results can be fed back
Knowledge Base
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Contains facts about a specified application
Facts and relevant data about medical conditions/specified application
Contains rules
Contains knowledge from a wide range of experts
A rule base
Part of the knowledge base which is made up of all the rules
known to the expert system
Inference engine
Contains the reasoning method used to search the knowledge base
Software used is generalised so that it can be used to search a variety of knowledge bases
Uses standard searching methods independent of the application
For example a bottom up or top down technique
Expert System for a doctor
Ability to diagnose an illness
Suggest a recommended solution
Can combine the knowledge of many human experts
Ability to retain the information
Much faster than a human at diagnosis
Low error rate
Advice and recommendations are consistent
Implications of using Expert System in a hospital
Less time spent waiting to see the doctor.
Patient needs to feel confident with the computer system.
Only can be used for minor medical problems.
May give the computer incorrect medical condition leading to an incorrect diagnosis.
Patients with certain medical conditions may be able to spend more time with the doctor.
Difficulty understanding the medical language.
Accessibility/disability.
Devaluing the role of the doctor as a medical expert.
Doctors workload may decrease/increase.
Patient may leave without seeing the doctor/over reliance. Patient feels more comfortable with talking to doctor or a computer.
Lack of human contact.
Confidentiality other patients may be able to see your medical details.
EXTRA NOTES: IMPLICATIONS OF C OMPUTER USE
E XT RA N OT ES : C UR RE NT T RE ND S I N C OM PU TI NG ;
Robot manufacture (Robot in 9691/03)
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They can operate faster than humans
The quality of work is always consistent/high
Accurate and precise manufacturing
They can work in hazardous environment
Running costs are low compared to human wages
Continuous process by robots
Can work 24/7
E XT RA N OT ES : C HA NG ES IN L EI SU RE A ND A T W OR K;
Work at home:
For the Individual
Can combine work and family commitments
No necessity to live within travelling distance of work
Flexible working hours
Feeling of isolation
Difficult to allocate a room in the house as an office
Can save on commuting costs/business clothes
Distraction factor
For the Organisation
No need to rent expensive offices in cities
Saving money on heating/electricity
Greater reliance on technology
More opportunities to employ disabled people
More difficult to monitor the workforce
No concept of teamwork/no face to face meetings
Can attract a workforce from all over the world
The set up costs for WAN can be expensive
For society in general
Equal opportunities for parents
Improved family life as parent(s) is at home
Reduced traffic congestion as fewer cars on the road
Less pollution due to fewer cars on road more environment friendly
Prosperity is spread across the country rather than concentrated in commuter belts in cities
Lack of social interaction between people
Reasons why need a new computerised system (e.g. health centre)
Current system is outdated
Current system is too slow for the user
Current software does not perform its required task
Current hardware/technology is outdated
Current interface is not user friendly
The old system is unreliable
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PRIVACY AND CONFIDENTIALITY OF DATA; DATA PROTECTION ACT (9691/03 DATABASE);
Data security
Use of passwords to prevent unauthorised access/different levels of access
Use of physical measures such as stripe readers/biometric data
Keep backup copies in case of corruption
Data Privacy
Registration with data protection agency Enforcing/complying with the Data Protection law
Use of passwords
To prevent unauthorised access
Use of physical measures
Such as stripe readers
Use of firewalls
Use of data encryption
Use of spying cookies
Keep backup copies
In case of corruption
Data Integrity
Use of data validation
Use data verification
to ensure accuracy of data
Design relational database structures/normalise data
Preventing viruses
Record Locking
Keep backup copies
in case of corruption, fire
Data Protection Act
Personal data should be processed fairly and lawfully with the consent of the data subject
Personal data should be used for the specified purpose only
Personal data should be adequate and relevant for its intended purpose
Personal data should be accurate and up to date
Personal data should not be kept for longer than necessary
Personal data should be processed in accordance with the rights of the data subject
Personal data should be held securely, with no unauthorised access
Personal data should not be transferred to other countries that do not comply with any formof data protection laws
New facilities required
Compatibility with other health systems/centres
The legal requirements of the health centre information system have changed
The health centre is expanding due to more patients/doctors
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Limitations of current data protection legislation
Difficult to monitor individual applications
on whether they are abiding to the principles of the act
Individuals may find it difficult to source
who is holding personal data about themselves The changing nature of technology
requires constant reviewing of data protection legislation
Some parts of the world/outside the EU
may not comply to data protection law
EXTRA NOTES: HEALTH AND SAFETY;
Repetitive strain injury (RSI)
o Employee needs to take regular breaks
o Ergonomic keyboards/wrist rests
Radiation from VDU
o Anti-glare screen/filters
o Flat panel screens
Posture problems
o Adjustable furniture for users
Eye problems
o Employer pays for eye tests
o Anti-glare screens
o Change of focal length
Epilepsy
o Use of interlaced screenso Maintenance of VDUs to protect from flickering
ENVIRONMENTAL ISSUES
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