Electronic point of sale (EPOS) prototype system In Nigeria. Abstract The purpose of this project is to design an Electronic point of sale system (EPOS) prototype in telecommunication industry. The system have to be able to access customer’s details, calculate item sold and easy access to inventory database system designed with Microsoft visual basic and Microsoft access database.
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software IT has provide communication of network that helps to facilitates the
expansion of products, ideas and majorly resources among the nation
(Globalenvision, 2009).
Electronic point of sale (EPOS) software developed today enables business owners
as well as companies a suitable way of checking out customers and of recording
sales. It enables secure to store record of the store inventory in the database
system, as well as updating data when an order is processed. It also enables user
to print out receipts of a particular purchased item, it can carry out different
types of transaction on till either with a credit card, cash or paying a gift card or
voucher. In most cases it can be used to track customers, etc.
POS is an abbreviation for point of sale (or point-of-sale, or point of service). The
point of sale sometimes refers to the electronic cash register system. Point of sale
systems (POS) can be used in some hotels, stadiums, restaurants, casinos, as well
as retail environments (Cunninghams, 2008).
An Electronic point of sale (EPOS) software also allows users to input via keyboard
or mouse, and some of it could be designed to a touch screen interface (Buzzle
2010).Some year ago, in August 1973 the International business machinescorporation (IBM) announced the IBM 3650 and 3660 store systems, in 1973 new
registers that were driven by computers were introduced, such as the IBM 3653
Store System and the NCR 2150 that were, in essence, a mainframe computer
packaged as a store controller that could control 128 IBM 3653/3663 Point of Sale
Registers. This system was the first commercial use of client-server technology,
peer to peer communications, and local area network (LAN) simultaneous backup
and remote initialization. Other computer-based manufacturers were Regitel,TRW, and Data checker also in same year 1973 IBM brought the introduction of the
Universal Product Code (UPC) barcode readers to the point of sale systems.
Thereby in mid -1974, IBM 3653 Store System was installed in Pathmark Stores in
New Jersey and Dillards Department Stores. Programmability allowed retailers to
be more creative (Almyta systems 2010).
Furthermore, in 1987, the Point of sale (POS) systems became mostly based on
personal computer (PC) technology with the introduction of the IBM 4683. The
In this project there is a need for relationship between the primary data,
objectives, hypothesis, literature and the prototype system, a relationship table
was created in order to show how the prototype system is connected to other task
in this project (See Appendix A).
2.0 Literature Review
This chapter introduces basic concepts and topics related to the Power outage in
Nigeria, Basic issues will be discussed such as how to eradicate power outage in
Nigeria and the cost of power outages to business sector of the Nigerian economy
in order for communication industries to carry out normal operations without
power outage. One strong outcome of the study is that the poor state of electricity
supply in Nigeria has imposed significant costs on the business sector.
2.1 Electrical Power Outage in Nigeria
Generally, a power outage can be identified as a power cut, power failure or
blackout. This can be addressed as loss of electricity power to a specific area.
Nevertheless, there are different causes of power failure in electricity which can
easily cause damages to human and business operations.
It is fairly settled in the literature that infrastructure plays a critical and positive
role in economic development. Infrastructure interacts with the economy through
multiple and complex processes. It represents an intermediate input to production,
and thus changes in infrastructure quality and quantity affect the profitability of
production, and invariably the levels of income, output and employment.
Moreover, infrastructure services raise the productivity of other factors of
production (Kessides, 1993).
Currently in Nigeria, lack of electricity supply is one of major infrastructure
problem affecting the business sector. The typical Nigerian firm experiences power
failure or voltage fluctuations about seven times per week, each lasting for about
two hours, without the benefit of prior warning which may likely cause damages
such as spoiled materials, lost output, damaged electronic equipment, restarting
cost operations and distraction of business operations(Adenikinju, 2005, p.3).
In Nigeria, the National Electric Power Authority (NEPA) now Power HoldingCompany of Nigeria (PHCN) is responsible for power supply in Nigeria. However,
Station, Niger State (578.4 MW) and Shiroro Hydro, Niger State (600 MW).
According to the projections, IPPs are expected to contribute 750 MW by 2010while the proposed JVIPPs and other IPPs are expected to generate 2,790 MW and
1,365 MW respectively into the national grid. Before the end of 2010, officials are
optimistic of changing forever the bleak electricity situation in Nigeria (Ipsnews,
2005).
Furthermore, without adequate power supply Nigeria cannot achieve its potential
to help put things in comparative perspective, Nigeria’s power demand is
estimated at about 15,000 MW as at September 2009, peak generation supplied by
PHCN was 2,443 MW – less than 17% of the electricity needed, All the claims of
generating “over 5,000MW” recently by the administration’s officials are of course
the usual slogans, and a false one at that! By way of comparison South Africa has
40,000 MW of electricity for a population of 50 million people; Brazil has 100,000
MW for a population of 192 million people; the US has 700,000 MW for a population
of 308 million people; while Nigeria with a population of over 150 million people
only generates 2,443 MW at peak! (Nasirschronicles, 2009)
Currently in Nigeria, government regulations in the supply and trading of
infrastructural services prevent the possibilities of three other mechanisms: joint
production, satellite behaviour or shared production. The unreliability of NEPA has
led most manufacturers to incur extra costs for private alternatives. The generator
market is very vibrant. Most small gas-powered electric generating sets in use are
Japanese products (e.g., Honda, Suzuki, and Yamaha). Most of these products are
imported from Japan, while some are assembled in Nigeria by Holt Engineering
Limited, which the company is specialised in assembling Yamaha generators.
Moreover, many small-scale industrialists now prefer locally fabricated generating
sets, which are considerably cheaper than the imported brand names (Adenikinju
2005, p.20).
According to the World Bank, South Africa generates 40,000 MW of electricity for a
population of nearly 50 million, while Nigeria with a population of over 150 million
only generates 3,400 MW at peak. This translates to very disappointing levels of
electricity consumption per capita, thereby leaving some industries to perform at
epileptic levels, goods and services to be sold at prices that automatically adjust,
during power outages, to account for the expensive cost of production via
generating sets and a populace that is unable to take advantage of the latest
advances in technology and appliances. All this puts a painful strain on the already
difficult situation of Nigerian citizens who must in addition to be paying higher
prices for goods and services, also invest hard earned Naira to buy, maintain and
fuel power generating sets for the their homes (Nasir El-Rufai 2010)
2.2 Business perspective
There are some huge businesses in Nigeria that find it difficult to carry out dailyoperations, A business cannot be successful if there is power interruption, every
business organisation want to be successful in business, but on the other hand it is
a shame to Nigerian government for not providing the right infrastructural facilities
for the society. In general, there are arguments to proffer for massive investments
on the power supply in Nigeria that for purposes of effective communication of the
depths of sufferings and hardships faced by the people, this section will highlight a
few points (PMWorldToday 2010) these include the following:
It’s mostly about corruption. The failure of Nigeria to generate enough power to
meet even the modest target of 6000 megawatts that the government has set for
itself by December this year is largely due to corruption. However, apart from
fraud and corruption in the country, there is the absence of a creative way of
solving Nigeria electricity power failure; one solution would require the
exploitation of massive deposit of coal in Nigeria, This has succeeded in solving the
power problems in many countries at what amounts to a cheaper rate, at least in
the long run. Nigeria has a coal reserve of some 2.7 million tonnes, which is
expected to supply between 10,000-15000 megawatts of electricity. This rich
resource has been largely ignored by government’s overtime. In the same manner,
uranium deposits, confirmed in six states of the federation and used by more
advanced countries to produce electricity, have not been exploited by the Nigerian
government (234next 2009)
Finally, the issue of Nigeria inadequate power supply could be controlled by the
government and not private sectors, on the other hand if the government carry out
some of these suggestion it would be a great benefit to Nigerians.
3.0 Methodology and DesignThis section of the project refers to the set of methods and development used for
the system, project planning, interview, questionnaire, analyzing different types
of design methodology that could be used to develop the required system and the
key to design methodology and the best solution for each design.
3.1 Project planning
Planning a project is very important; it is the key to a successful project. Creating
a project plan is the first thing to think about when undertaking any kind of
project. In most situations some fail to realise the value of a project plan in saving
time, money and some problems.
Carrying out Planning at some level is basic to all human activity, and is really
applied with a common sense. This involves working out the task required and
how to work on it. Furthermore, Planning involves identifying priority needs and
opportunities, discussing and testing the various possible courses of action,choosing the most appropriate one, agreeing on what to achieve, calculating the
Interview is one of the methods which were used in this project. It is important
because, it is used for collection of information’s from client. It acts as a guideline
which provides idea on what user needs (user requirement). In general, interviews
were conducted in other to obtain the users requirement and experience using an
Electronic point of sale (EPOS) system.
Different type of tools could be used for conducting an interview, such could be
one on one, using online messenger e.t.c, and the tools used for interviewing of
client in this project is by the means of Skype Software. The Skype software is
reliable software which enables the world’s conversation, also it can be use to
make free video and voice calls, send instant messages and share files with other
users, It can also be use to make calls to landlines and mobiles (Skype 2010). (See
Appendix C).
3.3 Questionnaire
When planning a project it is necessary to acquire the right information which
would provide idea to make decisions. If the information is accurate, there would
be a high probability of making a good decision. But if the information is
inaccurate, the ability to make a correct decision is diminished. Reliable
information usually leads to better decisions (Walonick 2004, p.1).
It is necessary to design questionnaires because it is easy to analyze. Also data
entry and tabulation for well composed surveys can be easily done with some
computer software packages.This projects demand the collection of primary data from individuals, the aim of
designing a questionnaire is to get different views of people and responses which
could be usable for making decisions.
Designing a questionnaire is one of the best ways of gathering information. The
questionnaires in this project are designed with Survey Monkey tool. Survey
Monkey is a tool that helps in designing questionnaire and also can be customise by
users. It is very easy to use and very effective (c4lpt 2010). However, SurveyMonkey gives thousands of people feedback and also helps to analyse the feedback
Human computer interaction is basically about designing computer systems thatsupport people so that it can carry out their activities productively and safe
(Preece et al. 1994, p.1)
The fact that today’s system should be more efficient, reliable and useful in the
way it interacts with users, Users should be able to pass mostly only the most
important information and allowing the system to act in a more independent way.
Therefore the Human-Computer Interaction mechanisms will be investigated and
applied. “Human computer interaction (HCI) is concerned with many areas such asinteraction between people and computers. Successful computer systems are
building with understanding of the interaction between people and computers.
This is the vital part of the system’s design” (Macaulay, 1995).
With the use of Visual basic and Access database for the design implementation
there will be a need to consider for human computer interaction.
5.0 Implementation of the system
This section consists of various stages which contained choosing the programming
language, Implementation, using various programming and testing techniques to
fulfil the requirements. Also one of the most important parts was making a
connection between visual basic 2008 and access databases. All these processes
are described within this section.
5.1 Programming language
Two programming languages were chosen for the proposed system implementation,
Visual basic is a high-level object-oriented and platform independent language. It
has rich application programming interface (API) for network support, graphical
user interface (GUI) design and there are numerous visual basic projects to support
In the Access Database a table was designed which comprises the fundamental
building blocks of a database, it helps store of related information such as the
username and password of users.
Using database in the process is useful because username are been stored in it and
it can be retrievable of could be deleted form the database by the administrator.
On the other hand a user would not be abale to gain access to the system if the
username and password details are not stored in the database system. To gain
access to the system a username and password must be stored in the database for
the program to access the details.
Figure 9: Username and password table
Reset control button
The reset control button is similar to the every button but the only difference is
that it enables the user to clear the form. In most situations, some people make
mistakes and sometimes it is difficult to resolve, a user could enter a wrong
username or password in the text box by making a mistake, with the help of the
reset button users can easily clear the form and start all over rather than shutting
down the program (Reset button in figure 7).
Exit control button
The exit control button was implemented to allow users to close or next the
program. It is quite useful because it provides aid for users to close the program atany time, also programs must be properly rather than shutting down the system.
The system was implemented to display a message box if the username and
password is not recognized by the database system. Some possible exception mightoccur during the process of the system. Exceptions might occur when a user enters
an invalid value on the system or something missing in the form. Generally, users
cannot be perfect all the time sometimes an error occurs when carrying out a task,
but the best way of solving this problem is by providing an error message box
which act as a guideline to the users when having some difficulties.
According to Jakob Nielsen’s which states that error messages should be clearly
visible and educates users along the way (Useit, 2001), an error message box was
used to develop the system, In a process whereby a user inpits an invalid value in
the text box that is not in the database system, an error message pops up “Please
enter a valid username and password” the error on the screen occur because the
users has entered a value that is not recognized by the database. The error
message can also be a guide to the user because when the message displays, the
user would have an idea on what is wrong and what to do next time when using the
The sales and invoice form was implemented with Visual basic, it is very important
to users when dealing with customers. The components and control used has been
discussed in Figure.
It involves calculation of items; the form was designed for user accuracy when
dealing with customers .
Figure 23: Sales form
Also a print button control was implemented in order for users to print out
customers receipt. The process button control was implemented with visual basic
which deals with the calculation of quantity (Qty), item, unit price and price.
The sales and invoice form could perform some calculation such as the sub total,
Goods and Services Tax (Gst), Provincial Sales Tax (Pst) and total of item
purchased. The calculation was implemented in other to output Nigerian Naira.
5.7 Issues arising implementation
Some issues were encountered when implementing the prototype system in Visual
basic and Access database. The first issue is related to the connection of Visual
basic and Access database. Basically, working on different computers whencarrying out implementation could lead to data corruption, the proposed prototype
Table1: Test case product search form, login form and stock inventory form
Test Case Expected result Pass/Fail
1.
Type in a productname
The product name inthe product list was
selected and the
product description was
displayed
Pass
2. Type in any name
“welcome”
Error message “no
matching results were
found
Pass
3. Login with any
details
Error message “ Please
enter a valid username
and password
Pass
4. Add a product in
the database.
Added already Pass
The testing was done after implementing the overall system prototype to achieve
the users’ requirement.
6.2 Interview and Questionnaire Result
Some of the information received from the interview and questionnaire were
helpful in this project, it provides guideline and structure that lead to analysing
what the users need and how the system could be friendly. Some of the feedback
received when conducting the questionnaire was analysed with the use of an excel
sheet producing a bar chart to analyse the feedback obtained (See Appendix)Conducting an interview was very useful to this project; this was done with Skype
messenger and was documented. This means of gathering information act as a back
bone to developer whereby useful idea and how to design the prototype system
was acquire when processing these interview (See Appendix)
According to Jakob Nielsen Heuristic evaluation is a usability engineering method
for finding the usability problems in a user interface design so that they can be
attended to as part of an iterative design process (Useit, 2010).
The heuristic evaluation was carried out on the proposed prototype system in order
to identify usability problems or error in the user interface.
Process evaluation
The process of the software prototype system used waterfall approach. Waterfallapproach follows a particular life cycle in order to ensure success in process of
software prototype system, whereby the software development has to be created
after following the stages of waterfall approach:
First the system requirements have to be identified. In the project the system
requirements were identified and it was declared what have to be done in
order to achieve the users’ requirements.
The first prototype was created that would be an approximation of the finalsystem after implementation.
Designing the second prototype, developing an interactive user interface was
considered to meet the advanced requirements. Then the second prototype
was tested for accuracy.
Identifying programming language to be implemented on the system in other
to achieve a successful program and user requirement
The final system is designed. It has to satisfy the users and systemrequirements. In the project the system used database storage in order to be
able to meet the design specifications.
The final system is tested for accuracy and error checking, in the project the
final system was tested with a test case.
The waterfall model is a reliable and simple approach for the software prototype
system development process. It enables developer to proceed in sequence from
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