Documentation and Evaluation Stage

Documentation Stage

In documentation stage there are two types: For the end user and for future developers

• User documentation is like the instruction manual book to let the user know how to use the software or system.

This can consist of the following :

1. the purpose of the system/program/software package
2. how to log in/log out
3. how to load/run the software
4. how to save files
5. how to do a search
6. how to sort data
7. how to do printouts
8. how to add, delete or amend records
9. screen layouts (input)
10. print layouts (output)
11. hardware requirements
12. software requirements
13. sample runs (with test data and results)
14. error handling/meaning of errors
15. troubleshooting guide/help lines/FAQs
16. tutorials

• Technical documentation

It is for the developers or programmers who will improve the system or make some future improvements to the system or mantaining the system

This can consist of the following :

1. purpose of the system/program/software
2. program listing/coding
3. programming language used
4. flowchart/algorithm
5. input formats
6.  hardware requirements
7.  software requirements
8.  minimum memory requirements
9.  known bugs in the system
10.  list of variables used (and their meaning/description)
11.  file structures
12.  sample runs (with test data and results)
13.  output formats
14.  validation rules
15.  meaning of error messages.

Evaluation Stage

It is the stage where the system has been running, and the user compares the new system with the old one. If the analyst finds any problem by the feedback from the customer, the system will have to be re design again.

To evaluate the system, the analyst will:

1. compare the final solution with the original requirement
2. identify any limitations in the system
3. identify any necessary improvements that need to be made
4. evaluate the user’s responses to using the new system
5. compare test results from the new system with results from the old system
6. compare the performance of the new system with the performance of the old system
7. observe users performing set tasks, comparing old with new
8. measure the time taken to complete tasks, comparing old with new
9. interview users to gather responses about how well the new system works
10. give out questionnaires to gather responses about the ease of use of the new system

Hardware may need to be updated because:

1. of feedback from end users
2. new hardware comes on the market, making change necessary
3.  there are changes within the company which require new devices to be added or updated

Software may need to be updated because:

1. of feedback from end users
2. changes to the company structure or how the company works may need
3. modifications to the software
4. changes in legislation may need modifications to the software.

Development stage, testing stage and implementation stage

Here I am going to show you how the development stage, testing stage and implementation stage

Development stage

After your done Analysis and Designing Stage, you will start doing stage. Development stage is a stage to finalize all the files structure and put all the parts that you design or made into one single system. Example, if there are files, you organize it according to the type of file and make a file structure.

To make sure the right data is in the right file and are following the rules that are set, there are methods that are adopted to check this, which are Validation Routine and Verification Method (Which are discuss in the previous blog). These are test again to ensure unwanted data to be trap and to make sure all data in paper could be transfer into electronic system accurately.

 How you use the system (User Interface), after putting the system together, will be made in this stage, how will the input gather data and how will the output present the data. If there is a special hardware, it will be necessary to finalise how these devices are used with the system

Testing Stage

As the name of the stage is, this stage is for testing the system that you design. You will test each module in your system. After testing the modules, you test the whole thing. if it fails you go back with Development Stage. The reason to test it whole, after testing each module, is because some data could clash or there could be a issue when working with another file.

Testing will use many different types of data, which will be in one of three

Categories. Normal, Extreme and Abnormal. Let’s use an example : A date (dd/mm/yyyy)

ü  Normal: It is in the range of the type of data. E.g. the month, there will only be in 1-12, that is a whole number.

ü  Extreme: It is the most limits of the range. E.g. the month, the limit in months will be 1 or 12.

ü  Abnormal: it is beyond the range. E.g. The month, which shouldn’t be 13, 0, 1.34, -1.

Implementation Stage

After it works on the Testing Stage, you will have to replace the new version with the old one, but before you implant it, you must train you staff so they can work on the new system and change all the paper based file into the electronic system.

After you finish that, you implant it. There are 4 ways to implant it (Each with a disadvantage and advantage, it can be seen in the table below). Direct Changeover, Parallel Running, Pilot Implementation or Phased Implementation.

Direct Changeover: It is to directly change the whole system overnight or when the system isn’t busy.

  Parallel Running: The old and new system will be there, but the old one will slowly fade away and the new one will eventually take over

  Pilot Implementation: The new system will be placed only in one part of the company. If it proved that it works, it will go to another part of the company.

Phased implementation: The new system will be introduced step by step, when it works satisfactorily the whole system will replace the old one.

System analysis and Design

 

In this blog, I am going to show you about the system analysis and design. Here are the steps.

 

Analysis

It is a stage when the company or you check existing systems to see what they lack and what you can improve in your own system.

1.     You collect the data of the other/current systems

2.     See how the existing system works (e.g. their Input, Processing and output/result)

3.     Finding the Problems of the existing system

4.     Agreeing with the customer about the Target of the system

5.     Finding and agreeing with the customer about their requirement/Need

6.     Understanding about the customer’s needs

7.     Analysis about the cost of the system and the profit

8.     Modeling its process aspects

On the first step, which is collecting data, there are 4 ways you could do it: Observation is observing a person using the other/current system

Questionnaires are sending questionnaires to the customer to see their view on the existing system

Interviewing is a session to interview the customer/employee

Looking at existing paperwork is seeing the paper files that tell you how the system works. (Ex. manuals/instruction)

Design

This is the stage where you design and make your own system or the stage to improve your own system after the last stage, Evaluation and review, is done.

At this Stage, you design what it will look like (Ex. Screen layout, input and output form, file structure, etc.), what the system requirement is (Software and Hardware), selecting & designing rules and how the system works.

 Verification

A way to prevent errors when data is copied to another location/medium. There are 2 common ways, which are:

Double Entry : the data is entered twice. Then the computer compares the two data, whether during or after the data entry, if there are any differences between the two.

Visual Entry : It Checks the data for errors by comparing  the data on the screen with the original Documents

Validation

A process to see if the data meets the criteria when it is inserted to the computer. Here are some common techniques of validation when writing computer software:

Range Check = Check if data is within acceptable requirements

Length Check = Check the input data has the required numbers of Character

Character Check = Check if it has no invalid characters

Format Check = Check if the data is in a specific Type/Format

Limit Check = Check to see the Limit or how far can it work

Presence Check = Check if the data is there and not missed

Consistency Check = Check to see if each field is tied up/ responding to each other

Check Digit = Check if there is a mistake in the data in digits

Banking Application, Expert System, Library System

Banking Application

The use of computer technology has been better and better, now we are going to learn about it.

ATM: Allows almost anywhere access to your money; transfer, check balance, take money, change

ATM or automatic teller machine is the machine where people can do transaction with money or even can take money out from it.

Library system: it is used in the library to keep check on the records of who borrowed the book and what book is borrowed everyday.It is also used in the library to keep check on the records of who borrowed the book and what book is borrowed everyday.This system makes the librarian easier to do his work rather than recording it in a book. This system needs a barcode so that it can just be scan by a scanner like in the supermarket.

The expert system

It is developed to mimic the expertise and knowledge of an

diagnosing a person’s illness

[1] diagnostics (finding faults in a car engine, finding faults on a circuit board, etc.)

[1] prospecting for oil and minerals

[1] tax and financial calculations

[1] chess games

[1] identification of plants, animals and chemical compounds

[1] road scheduling for delivery vehicles.

Knowledge Base = a database that  allow complex storage and retrieval requirements of the management system

 Rule Base = It is similar to a 'Setting' option of an application

Inference Base = It is like a rule base, but focuses more to the system and not how the program looks like. It is also a type of a reasoning engine

How to set up an expert system:

Experts in the field are interviewed to find out what is needed in the expert

system.

Data is then collected from these experts.

A knowledge base (defined below) is designed and then created.

The rules base (defined below) is designed and created.

An inference engine (defined below) is designed and created.

The input screen and output format are also designed and created – this is

known as the user interface.

The expert system is tested against known conditions and scenarios.

It is also checked to see if it meets the original specification.

Experts are interviewed about how effective it is before the expert system goes

out on general release.

Advantages

Expert systems provide consistent answers.

They never ‘forget’ to answer a question when determining the logic.

Using expert systems reduces the time taken to solve a problem.

A less skilled work force is needed, which gives the potential of saving money,

but also allows areas of the world access to expertise which they could not

normally afford.

Disadvantages

They tend to lack common sense in some of the decision-making processes.

Errors in the knowledge base can lead to incorrect decisions being made.

It can be expensive to set up in the first place.

Considerable training is necessary to ensure the system is used correctly by the

operators.

•Chip and Pin: to ensure higher security rather than signatures, every chip and pin is different, a magnetic strip of your card has a unique pin which has been registered to your account or balance, it can also be used to pay in restaurants and shops. 

Tuck Shop model, Traffic light simulation, Architectural simulation, Types of processing

Tuck Shop

A program that’s stores information/records in a spreadsheet (Similar to Microsoft Excel) for a period of time. It could also change a data if the data changes in real life. EX. A supermarket, a school supply shop, etc

Traffic Light simulator

It simulate a scenario about traffic light. It simulate with the data gather, either manually or by a computer.

Information gathers:

·        How many cars pass in a weekday, weekend or holiday.

·        Direction cars go to

·        Time taking for a average car to finish the junction

·        Time taken for the slowest car

·        How pedestrian crossing over effect the traffic

The profit for this is      :

ü No risk when trying out scenario

ü Testing all scenario takes less time

ü Expenses for testing the scenario is cheaper

Simulations are used because it is less expensive than building the real thing.

Architectural simulation

Architectural simulation is a simulation on buildings. This is to test if the building could hold and what is its limitation. The information needed is basic physics and what material will the building use.

Just like the traffic light simulation, it is safer, cheaper and faster if you simulate this than testing it in real life. It could even simulate if the building will get damaged in certain weather.

 3 Types of Processing:

1.   Batch processing

2.   Real Time(transaction) or online processing

3.   Real time process control

Batch processing is the execution of a series of programs on a computer without manual intervention. It is often use in Banks, Billing System and Payroll system. It doesn't need to update manually, it will update automatically, when the system is less busy (e.g. overnight when people are less active). It will update  its main server and it will do it frequently.

Real-Time (Transaction) or online processing

It is an example of Online processing, and it could be used in Theatre, ATM, flight and etc. Unlike the Batch processing, this will have to be faster, to prevent 'double booking'. It will update as fast as possible to its main server. This process has a time lag and isn't instantly updated

Real-Time Process Control

Real-time Process Control is instant process. There is no time lag. It is also an example of online processing. It is used in games, where is needs no lag when playing. It is also used when measuring physical quantities.

Batch Processing applications,Automatic stock control, online booking system

Batch Processing applications

Batch Processing

·         Use to process a lot of data and a fast response time

·         No data is processed until a complete batch has been put together

·    

Three types of transaction:

1. ·         Add
2. ·         Delete
3. ·         Update

Before process

·         Validating = each transaction is check again

·         Sorting = sort using a primary key

Advantage

·         Cheaper and easier real-time system

·         It is automatically, when it is less busy.

Disadvantage

·         The time lag is not so fast when updating

·         A delay when processing before work and when the output is obtained

Payroll System:

Payroll system is an application that are used to count the wages of every employees at the end of the week or month and also to print it using the information in its server.

Input : First it reads the detail of the Employees, the time that the employees worked and any overtime duration

Process:  gross pay, any deduction (e.g Tax) , etc

Output : Print the Slip(Check), update the file, Transfer money to the Bank account of the employees if they have Bank account

Billing systems

Companies send their bill on a pre-determined date, so that theyu send their bills in one batch.

Inputs: customer details (address), charge per kW (unit) of power, previous readings, new readings taken from the electricity meter, bank account details.

Process: the process is done by the calculation of number of units of electricity used, customer’s cost, monthly payments made (if using direct debit), outstanding amount owed or carried in the next bill.

Outputs: bill showing all the details, updating of customer file, production of request for payment if not done through direct debit

Automatic Stock Control

 Automatic uses a Barcode. With this the identification of the item will be faster in the cashier with a barcode reader. Barcodes are made up of alternating dark and light lines of varying thickness barcode usually consists of four parts: country code, manufacturer’s code, product code and a check digit.check digit is a form of validation which is used to make sure no errors occurred during the reading of the barcode.

Here is the example of a barcode reading:

  1    3    5    7    9    11      odd digit position

  4 7 2 8 4 6 9 3 2 2 1

     2    4    6    8   10           even digit position

even numbers: 7,8,6,3,2

odd numbers:4,2,4,9,2,1

Add together the digits in the odd positions and multiply the sum by 3:

(4+2+4+9+2+1) times 3 = 22 x 3 =66

Add together the digits in the even positions:

7+8+6+3+2= 26

Add the two results together: 66+26= 92 

To find the check digit, calculate what needs to be added to 92 to make the next

multiple of 10 i.e. 100

.Hence the final code is 4 7 2 8 4 6 9 3 2 2 1 8

Barcodes are used in the following applications:

1. library book systems 
2. administration systems 
3. passport and ID card systems
4. some burglar alarm systems
5. equipment checking systems 
6. automatic stock control systems 

·       Stock control system are   system that monitor the item in stock, to know if it is too much or too little to all items

·         It works just like Microsoft Excel (spreadsheet)

·         Example: for stores

·         When a item is added or taken, the system will record it

·         The system will check if the item is less than the quantity that the market needs.

Advantage:

·         Make updating easier

·         Instant feedback

·         Sales are shown

·         Re ordering can quickly be done

Disadvantage:

·         Complicated

·         Expensive

·         Staff training

·         If the system broke, the whole place will be confused

·         Need backup plans

·         Staff needs to remember to update

Online booking

·         Website

·         Example is booking flight

·         In the website, you can see the flight available

·         You can book seats/rooms in the form from the website

·         The details will transferred to the central database, which will be update

·         It uses real-time transaction processing so that if the seat is taken it will give the information that the seat is not available anymore

·         They have strict changes so only one person can change it.

Advantage:

·         Save time

·         Saves money (in transport), by not going to the place where we need to buy the ticket we can save fuels and money

·         Easier

Disadvantage:

·         By fake website, our personal info can be stolen

·         It is hard for the one that can’t use the internet

·         Hard for someone that doesn’t have any gadget or PC

Turtle Graphics, Robotics

Turtle Graphics

What is it?

A method of programming specifically designed for children to do some basic programming

A method of programming

By controlling the movement of the ‘turtle’ on the screen by typing key instruction for it to move

What does it affect in everyday life?

It is used to carry out drawing functions for Programming the graphics by drawing.

What’s the profit and lost when using it?

Application using sensor

What does it affect in everyday life?

Monitoring: Burglar alarm system

fingerprint-based attendance management system

Record in the data will be accurate and more secure (updates the data overnight)

 Controlling:  Greenhouse Environment

                        To control its environment.

What’s the profit and lost?

Monitoring   : Lost: Expensive, May break down, easily set or hacked and can cause problems

Profit: Efficient, Accurate, Can be taken more frequent, Updates automatically, and keeps data safe

Controlling   : Profit: Safer, Direct response, Accurate

How does the sensor affect the control?

Monitoring: collects data and updates the files or data. It will give notice but does not result changes.

Controlling: reviews the data from the sensors. It will give notice and automatically changes the process

Sensor Lens or Light, how does it work?

Light:  image control street light control: it computes the amount of vehicles in a street. If there’s snow on the street, it will be dimmer because ice can reflect the light.

Photocells: light can be controlled by photocells. These are light-sensitive sensors that responds to the amount of light detected.

Example : Washing Machine

It has the sensor to detect how much time is needed to dry the clothes

 Robotics

Robotics is a computer science

One of the ways ICT is used.

It is used in manufacturing

The profit and lost when it uses ICT

Profit : Efficient, doesn’t need wages, Higher productivity, don’t have any feelings, Can work in a harmful environment

Lost    : Difficult to do ‘unusual task’, Replace skilled labour, risk of de-skilling, Factories can be moved, Causing unemployment