Wednesday, November 23, 2016
Wednesday, September 14, 2016
How The Internet is changing the face of journalism
The
internet can be described as the fastest way to disseminate information now.
With the advent of internet, a lot of things have changed. Gone were the days,
when one has to wait for a longer time to get information or send information.
I can sit in my house, or anywhere, get a story and lease it to my media house.
For example, with social Medias like twitter, Facebook, and blogging, I can do
a story and let other people know. In other words, internet has made the
compression of time and space very possible.
Another
factor is also that new organizations don't own the news anymore. There is a
transformation for the journalist from being the gatekeeper of information to
sharing it in a public space. Therefore citizen journalism is something that
the internet has brought. For example, here in Ghana, TV3 has given the public
a chance to make their own news. So I can make or write the news in my locale
and send it to them via the internet.
The
only thing I can say is that when it comes to objectivity, then the internet
raises a lot of questions. Objectivity has always been an idea important for
the news. It is designed to deliver journalism that people can trust. But in
the new media age transparency is what delivers trust. News today still has to
be accurate and fair, but it is as important for the readers, listeners and
viewers to see how the news is produced, where the information comes from, and
how it works. The emergence of news is as important, as the delivering of the
news itself.
Journalism
now has been given a new branding. The Internet makes organizing groups
trivially simple. A mass e-mail, a facebook group, or an online petition can be
created in seconds and at essentially no cost. Collaboration on any significant
scale used to require the power of institutions and organizations. Now they
require only a good idea and the right tools.
With
the Internet, retailers don’t need newspapers to connect with their customers;
they can set up their own Web sites and mailing lists. I can start a blog and
post leaked documents to my hearts’ content.
Deciding
what combination of news was the most important for the public to know.
Traditionally, that’s been a job for newspaper editors, the ones who decide
what makes Page One and what gets cut for space. But space isn’t a limited
resource anymore; there’s no shortage of electrons. Instead of trusting the
local paper’s brain trust to judge what’s important, any Internet user can get
their news through the filter of their choice—a favorite blogger, the
machine-generated Google News, or the Most E-Mailed list on some news site. Or
they can find news about the near-infinite number of subjects.
Blogging
sites also represent a step forward in Journalism. As mentioned earlier on, one
can find any information on a blog or post information on blogs depending on
varied topics. Gone were the days one need to look through a lot of books or
journals on a host of topics. Blogging helps now with a lot of findings because
people post their opinions for other people who will be interested to follow.
I Promise NOT to Promise (Part 1)
The election season is here in Ghana once again. One cannot begrudge the hopefulness of everyone standing for election to public office. Even the bloke who is very much aware that members of his own family wouldn't vote for him if even he was the sole candidate is brimming with hope that he will be given the nod.
I have always wondered - once I attained such capacity - why politicians would do everything and anything to get elected; in fact why it becomes a do or die affair to serve the people. Woe anyone who stands in in their way towards attainment of such "noble aspirations".
Noble Aspiration? Indeed. I believe public service is a noble aspiration which we must cultivate. However, selfishness appears to be the drive of most of the people who seek public office today. Why not? We see the tremendous change that comes upon those who occupy such positions; from the lavish homes to the high-end vehicles they would hitherto not have bothered to read the prices off of magazines. Who no dey love better chop?
Promises are a regular part of campaigning. Politicians would promise reincarnating your mother if that you would get you to vote for them. The mischief is that most politicians who make these promises have no intention of keeping them or do not properly think through their promises before pronouncing them.
The presidential candidates of almost all the political parties in Ghana have recently made some promises, some major, some minor. Some of the major promises made by the NPP presidential candidate, Nana Akuffo Addo, include 1 village in the North 1 dam, 1 district 1 factory, creation of a new region carved out from the Western Region. The president and candidate of the NDC wouldn't be outdone; he came out with the promise to increase the number of regions to 15, build more community day schools, 1 student 1 tablet, etc.
Of course the crowd goes wild upon hearing such promises. But people who have observed the political history of promises in Ghana would tell you that the bigger the promise, the more likely that the candidate making the promise has no intention of keeping it. The primary reason for this is that they make such promises as a counter to other promises made by their opponents and so do not properly think through the implications of their promises within the context of prevailing capacity and resources.
My Critique of some promises I find Unnecessary
Mind you, I think very little is impossible. Now with that out of the way what are some of the promises which I think are unnecessary or achievable within any four year tenure of a president.
1. One District, One factory:
I personally believe this is possible but unnecessary. First and foremost, the promisor has not defined what type of factories he is thinking about only that "every district has a dominant industry". But factories by themselves are nothing if they are not assured of regular market and raw material. Again, if we intend being relevant to modern trends, government has no business setting up factories. I would rather that government create an enabling environment for the private sector to thrive. At least our history as a country has taught us that much. It is unnecessary because of the simple law of diminishing returns.
To be continues.....
Thursday, July 28, 2011
The Masters have Spoken
I just can not get this thought out of my mind, try as I may. I believe I've lived in a delusion, studied a delusion and become so immersed in a delusion that my life (and millions others) has become an illusion.
Is it true that I am free, as an AFRICAN youth, to decide which way of life I want to live (influenced only by the tradition and culture I was born in)? I've, all along, thought this to be the case until recent events have culminated in one final conclusion...AS AN AFRICAN, I AM STILL A SLAVE TO THE DICTATES OF SOME WHITE FOREIGNERS.
Are you shocked? Trust me, I was likewise shocked when I arrived at this conclusion. I've always celebrated the independence anniversary of my motherland with such fervent zeal and pride. Unknown to me, all that I celebrated was the anniversary of CHANGES IN MODE OF FOREIGN RULE; what was done directly, is now done indirectly, using my own people as tools of oppression. I blame no one but my own people for allowing this sad state of affairs to go on till now.
I heard on BBC radio this morning that the UK government had decided to deal with REBELS ( The rebel transition movement) of Libya and thus sacked all diplomats who were stationed there during the time of Gadhafi. The same initiative has been carried out by the French and American governments. Till date, the has been no stance from AU countries and the UN. When did the word REBEL ever signify the locus of a justified moral mandate to rule?
One thing which a lot of people have failed to take notice of is the fact that the guns which US, France, Uk and other NATO forces have brought into Libya will stay long after Gadhafi is dead and gone. Now it has been made clear by these SAVIOURS of the world..."if you feel that you are oppressed, it is perfectly OK to pick a gun and fight to be heard; just make sure you gain the sympathetic ear of enemies of your oppressor". A typical case of "the enemy of my enemy is my Buddy". Why...is Libya now a UN,US, FRENCH or NATO protectorate and no more Sovereign? Where lies the say of the Libyan people? Is this democratic?
Why do I think my own people have contributed to this sad state of affairs? United States of America (which consists of 51 states/countries, if you will) have made it a point to stress their unity as opposed to their diversity and thus become self-sufficient. You might argue that they have become a federation so it is logical. What about the European Union (27 countries)? Each maintains its sovereignty but each must meet its assigned quota while contributing to one another's maintenance so as to bring balance to the union. The AU has 54 countries and surpasses any other Union in natural resources yet we can't even feed our people, take active part in geopolitics nor become self-sustaining as a unit. When something happens on this continent, the AU is the last to react after the individual and collective countries of both the East and especially the West have already analysed, seen what they stand to gain from the present chaos and long since acted to satisfy their parochial interests.
If we are indeed free to determine our destinies as African States, then we had better live within our means, manage our resources better, breed patriotic citizens, and ultimately harness national leaders who are not greedy or allow their selfishness to be used as a snare to entrap the people they are sworn to protect.
If indeed we are free, we should not draw up budgets which have to be supported by foreign donations (donations which are used as baits to trap us). Development is a process and cannot be done in a single day or in a single presidential term. Leaders need to do the best they can with the limited resources at their disposal and opposition leaders need to lend concrete alternatives to present issues, but not to make it a habit to continually take opposing views to what is apparently a good course of action without providing better alternatives. Heads of states should play by the rules of the game, rules they knew way before they decided to engage in the game of politics. If a leader's term is over, it is OVER. Let another also manage the problem of the state.
If indeed we are free, why do ambassadors from western countries seem to hold more power on our leaders than the people who put them in power? Can any country within Africa fly a fighter jet into an EU or allied country experiencing rebel/terrorist attacks just because it can?
We, as Africans, are still under the command of foreign masters who have used all manner of means to keep us under check and servitude.
The masters have spoken on the Libyan crisis and chosen a leader for them just like in the colonial days. We await to see if other african leaders will follow the dictates of their colonial masters.
Sunday, April 3, 2011
LIBYA
I think I got to express my opinion in relation to libya. I will do this by mere questions. Here we go:
What is the reaal issue at stake right now in Libya?
Where are the so called African Union Leaders?
What is their take on the issue in Libya?
Are the security council, NATO, and the so called allied forces oblivious of what is happening in Ivory Coast?
Can African countries form an aliance to invade any country in Europe and the States?
I am not judging anyone but just asking questions and the answers to these I believe will be your opinion as well.
If I manage to find out the answers to these my next questions will give me a clue.
Issues in Libya? They are people's opinions. As it is said, opinions are like noses and people have their unique ones.
What is the reaal issue at stake right now in Libya?
Where are the so called African Union Leaders?
What is their take on the issue in Libya?
Are the security council, NATO, and the so called allied forces oblivious of what is happening in Ivory Coast?
Can African countries form an aliance to invade any country in Europe and the States?
I am not judging anyone but just asking questions and the answers to these I believe will be your opinion as well.
If I manage to find out the answers to these my next questions will give me a clue.
Issues in Libya? They are people's opinions. As it is said, opinions are like noses and people have their unique ones.
Thursday, March 31, 2011
LIBYA AND THE AFRICAN LEADERSHIP
The past couple of weeks have seen some of us totally shocked. Why, you may ask. And my reply, why not? A whole continent stood silent while one of its member States (which was probably the most peaceful, promising and progressive) is being laid siege to by hounds from the West under the guise of wanting peace in that country. Admitted, Col. Gathafi may have overstepped the bounds of leadership when he started killing demonstrators. But the question to be asked is “How soon can a band of peaceful and spontaneous demonstrators become a hardened gang of Rebels, wielding tanks and other sophisticated weapons?”
In recent times, a wave of demonstrations has spread through some Northern African States, most of which have turned violent. The commonest reason by the demonstrators irrespective of their origin has been the fact that leadership in their respective countries was either insensitive to their needs or had been in power too long. Often times, these demonstrators have succeeded in getting their way prompting a change in leadership, usually with very little violence. However, Libya appears to be an exception. Gathafi appears to have played directly into the hands of some unseen conspirator(s).
Gathafi has always not been the best friend of some Western States, especially the most powerful ones. He has always advocated for a United Africa, just like Dr. Kwame Nkrumah dreamed of. The obvious conclusion can only be drawn from the way the West handled/is handling these two.
Let’s take a moment to look at what USA did to Osagyefo Kwame Nkrumah. He was the target of a series of assassination attempts which gradually pushed him to become paranoid and ended up making certain political decisions which later came to haunt him. First, he instituted the law that made it possible for a person to be arrested and held indefinitely without trial. Secondly, and sadly so, he made Ghana a one-party State. These same reasons were what his detractors cited as the reason for his overthrow. However, it is now common knowledge among Ghanaians that USA aided the coup makers to overthrow Nkrumah thereby overthrowing the dreams of Ghana becoming an industrialized Nation. Ghana has still not recovered, thanks to the puppet strings controlling most of her political leaders and the false promise of a better world anywhere in the world apart from Ghana, which the young and enterprising youth have been made to believe.
Gathafi has also been led to make the same mistake. He sought to use force to stamp out people who were portrayed by the media as “Demonstrators” but whom he saw as “Rebels”. The use of force was subsequently reported by these media thus winning international sympathy for the Demonstrators/Rebels. Now, Gathafi is made out to be the bad person. As is to be expected, USA has gotten UN to grant her permission to enforce a no-fly in Libya where only US and French, and now NATO fighters can fly and bomb Libyan targets at will (when anti-aircraft missiles could have been used to prevent Gathafi’s planes from flying and thus avoid the indiscriminate bombing of innocents).
If you ask me, this trick is as old as the vanishing coin act.
a. Plant people within the area you wish to destabilize, preferably co-opted, corrupted or disgruntled members of that same society.
b. As they infiltrate, give them the means to cause little, isolated acts which will only serve to incite established authority to action.
c. Make sure the media is readied to capture the reaction of authority, with a slant in favour of the inciters, who are to be portrayed as the disadvantaged minority.
d. The UN will be forced to take action. Guess who volunteers to help the UN (you got that right)…ALMIGHTY AMERICA, THE SAVIOUR OF THE WORLD.
If by this time African leaders have not grown the clout to deal with African problems, then I dare say we are still colonies and have no right to celebrate independence days across Africa. Why is it that America, France, NATO and indeed UN have not attached the same sense of urgency with which they are dealing with Libya? African leaders, be smart.
Wednesday, February 23, 2011
OUR GREAT KINDERGARTEN
Remember when years gone by when what mattered most in the world was to hurry to school in order to sing the alphabets as if they were songs and then hurry up home to play a game of crown-cocks? At that time, nothing else mattered except the things that friends said which got you agitated enough to take away your plastic ball before the football match was over; "m'agye me ball" .
Funny enough, that is what the whole political life is gradually becoming. We spend a lot of money and other resources bantering about the possible meaning of what someone said some days ago to some group of people, or possibly psycho-analyzing him/her in order to read meanings hitherto unintended when some speech was made. After all, we have a more than willing gossip crew who in the name of investigative journalism become serious threats to our national security without even knowing their error.
Nowadays, it is almost as if a current journalist is one who succeeds in getting a politician or his/her allies to lock horns in a never ending give and take of what some political figure did to cause the under-development of this nation and where the nation would have been had he/she not done what he/she already did. While it is good to get different sides of a story, journalists should understand that they owe it to the masses, most of whom depend on them for information, to report accurately what was said without adding their own flavors and seasoning to the facts. The whole issue of analysis should be left to experts who are expected to be impartial and unbiased. But it appears in Ghana, politicians and journalists have become experts in all areas of national life; from religion, through education, economics, medicine, and the list goes on.
What is achieved at the end of the day is that we have a lot of wrong versions of true facts out there that the listener is left totally confused. To make matters worse, radio and TV panelists are made up of representatives from political parties instead of analysts who are believed to be experts in their chosen and respective fields. Only in so doing can we achieve any value from the national political discourse. At the very least, when faced with facts, expert analysts agree unlike party faithfuls who would rather defend the indefensible. After all, who would ever want to be accused with pointing the left hand to his/her father's house?
Current events have saddened me to the extent that were I with super-human powers, I would immediately cause some serious discomfort to all responsible for completely diverting national attention from more important issues to banter about trivialities, such as the level of remorse the president had when he apologized to former President Kuffour and the Chief Justice, or what Akuffo Addo meant by "all die be die" and for that matter, which category of people make up Akans according to Akuffo Addo. As a people, is it not just plainly reckless to leave such issues as how to block the revenue leakages at the ports, improve education, energy, transportation, employment, etc. in order to talk about comments passed by one person or the other which, in the long run, would not be valid contributions to the main issues of national development?
We have become a nation of toddlers who have failed to see the necessity of keeping our country clean, respect our elders and leaders, think of making rather than consuming products, solve problems rather than cause them, show good initiative rather than thwart existing ones, and the most disheartening of all, allowing ourselves to be led astray by a few favor-seeking, fame-thirsty and power-hungry individuals who would do any and everything to see that they are the center of attention and none other.
If we are not able to change, then election periods will always become volatile moments when any little thing would plunge the entire country into chaos or worse still, war. The youth should know that they are better than they are made out to be by some unscrupulous politicians. They have what it takes to make it in life without tying in their lot with politicians to curry political favor. The Journalists whose careers are built on sensationalizing every bit of news item should be aware that the instability the court will affect them as well in the event that the nation bursts into flames. As for the few bad nuts within the political parties, the question is at what point is the state more important than personal interests?
Funny enough, that is what the whole political life is gradually becoming. We spend a lot of money and other resources bantering about the possible meaning of what someone said some days ago to some group of people, or possibly psycho-analyzing him/her in order to read meanings hitherto unintended when some speech was made. After all, we have a more than willing gossip crew who in the name of investigative journalism become serious threats to our national security without even knowing their error.
Nowadays, it is almost as if a current journalist is one who succeeds in getting a politician or his/her allies to lock horns in a never ending give and take of what some political figure did to cause the under-development of this nation and where the nation would have been had he/she not done what he/she already did. While it is good to get different sides of a story, journalists should understand that they owe it to the masses, most of whom depend on them for information, to report accurately what was said without adding their own flavors and seasoning to the facts. The whole issue of analysis should be left to experts who are expected to be impartial and unbiased. But it appears in Ghana, politicians and journalists have become experts in all areas of national life; from religion, through education, economics, medicine, and the list goes on.
What is achieved at the end of the day is that we have a lot of wrong versions of true facts out there that the listener is left totally confused. To make matters worse, radio and TV panelists are made up of representatives from political parties instead of analysts who are believed to be experts in their chosen and respective fields. Only in so doing can we achieve any value from the national political discourse. At the very least, when faced with facts, expert analysts agree unlike party faithfuls who would rather defend the indefensible. After all, who would ever want to be accused with pointing the left hand to his/her father's house?
Current events have saddened me to the extent that were I with super-human powers, I would immediately cause some serious discomfort to all responsible for completely diverting national attention from more important issues to banter about trivialities, such as the level of remorse the president had when he apologized to former President Kuffour and the Chief Justice, or what Akuffo Addo meant by "all die be die" and for that matter, which category of people make up Akans according to Akuffo Addo. As a people, is it not just plainly reckless to leave such issues as how to block the revenue leakages at the ports, improve education, energy, transportation, employment, etc. in order to talk about comments passed by one person or the other which, in the long run, would not be valid contributions to the main issues of national development?
We have become a nation of toddlers who have failed to see the necessity of keeping our country clean, respect our elders and leaders, think of making rather than consuming products, solve problems rather than cause them, show good initiative rather than thwart existing ones, and the most disheartening of all, allowing ourselves to be led astray by a few favor-seeking, fame-thirsty and power-hungry individuals who would do any and everything to see that they are the center of attention and none other.
If we are not able to change, then election periods will always become volatile moments when any little thing would plunge the entire country into chaos or worse still, war. The youth should know that they are better than they are made out to be by some unscrupulous politicians. They have what it takes to make it in life without tying in their lot with politicians to curry political favor. The Journalists whose careers are built on sensationalizing every bit of news item should be aware that the instability the court will affect them as well in the event that the nation bursts into flames. As for the few bad nuts within the political parties, the question is at what point is the state more important than personal interests?
Thursday, December 9, 2010
UML
SYSTEM ANALYSIS AND DESIGN
QUESTION 1
The University is considering a new system to speed up the student registration process. As a systems analyst, you are asked to develop a plan for fact finding.
(a) List all the information gathering techniques that all systems analysts must be able to use.
(b) Explain any three of the techniques listed.
(c) Explain the criteria for selecting a given technique.
Solution
(a) Interviews
Questionnaires
Observation
JAD (joint application design)
Document Analysis
(b) (i)Questionnaires
This is the mode of gathering data from sampled participants in order to understand an existing system or know the expectations of a new one. The researcher sets off by firstly carefully designing the questions which would best reveal the desired information he so desires.
He, then, goes ahead to administer these questionnaires to his sampled participants and makes sure that they answer them. This is done through follow-ups. But care should be taken that the one administering the questionnaires has good inter-personal skills in order to have a successful survey of opinions.
(ii) Interviews
This technique also involves gathering information from people though in this sense, one would have to talk to his interviewees and ask them relevant and well-crafted questions in order to receive relevant answers. The interviewer is to be able to respectfully steer the conversation/interview to areas of his interest while sifting through all that the interviewee would say.
To engage in a successful interview, the interviewer must first select his interviewees (people he thinks are in a position to know what he needs to know). He can then proceed to formulate concise and relevant questions which he would use to both prepare and conduct the actual interview. It is necessary that after the interview, there be a follow-up by the interviewer in a bid to re-gather vital information interviewees might have forgotten to share, and also probably give them feed-back on the previous interviews.
(iii) Observation
Because people cannot always remember everything they do and the fact that they tend to act differently from their usual selves when they know they are being watched, there is need to independently verify information gotten from them through different methods. Observation is that technique of gathering information without the involved parties becoming aware of it. The Observer should make sure to be discrete, unpredictable and attentive to everything that happens regarding his subjects so that he can read trends which can be compared with information gathered through other sources.
(c) When choosing an information gathering technique, one should take into consideration
1. What type of information is being sought?
2. What is the gravity of the information being sought?
3. What is the scope of the information being sought?
4. Which technique can give corroborated information?
5. Is there need for users to be involved or they can circumvented?
6. What is the comparative cost in getting relevant information through the use of any given technique?
QUESTION 2
(a) What is UML?
It is the abbreviation for Unified Modelling Language. Since a model abstracts the essential details of the underlying problem from its usually complicated real world, it is necessary that there be a standard set of tools which can be used to organize/develop these models so as to allow many categories of people understand them.
Explain the use of the following diagrams:
(i) Use Case diagram:
They are UML diagrams that describe what a system does from the stand-point of an external observer. This is gotten from the fact that a use case, per se, is a summary of all the scenarios for a single task. It is made up of an actor (the user of the system), a use case (what the actor uses the system for) and an association (the actor’s relation to the use case). Thus a use case diagram is a collection of actors, use cases and their relative associations.
They are useful in that they, primarily, help in determining system requirements since new cases may elicit new system requirements as the diagram takes shape. They also aid communication between system developers and clients through the use of relatively simplified diagrammatic notation. Finally, they are useful in generating test cases in that the associated scenarios give a perfect collection of test cases for the system.
(ii) Class Diagrams:
A class diagram gives an overview of a system by showing its classes and the relationships among them. Class diagrams are static in that they display what interacts but not what happens when they do interact. This is from the background that a class is a template for merging attributes and behaviours into a single distinct entity, an object.
QUESTION 1
The University is considering a new system to speed up the student registration process. As a systems analyst, you are asked to develop a plan for fact finding.
(a) List all the information gathering techniques that all systems analysts must be able to use.
(b) Explain any three of the techniques listed.
(c) Explain the criteria for selecting a given technique.
Solution
(a) Interviews
Questionnaires
Observation
JAD (joint application design)
Document Analysis
(b) (i)Questionnaires
This is the mode of gathering data from sampled participants in order to understand an existing system or know the expectations of a new one. The researcher sets off by firstly carefully designing the questions which would best reveal the desired information he so desires.
He, then, goes ahead to administer these questionnaires to his sampled participants and makes sure that they answer them. This is done through follow-ups. But care should be taken that the one administering the questionnaires has good inter-personal skills in order to have a successful survey of opinions.
(ii) Interviews
This technique also involves gathering information from people though in this sense, one would have to talk to his interviewees and ask them relevant and well-crafted questions in order to receive relevant answers. The interviewer is to be able to respectfully steer the conversation/interview to areas of his interest while sifting through all that the interviewee would say.
To engage in a successful interview, the interviewer must first select his interviewees (people he thinks are in a position to know what he needs to know). He can then proceed to formulate concise and relevant questions which he would use to both prepare and conduct the actual interview. It is necessary that after the interview, there be a follow-up by the interviewer in a bid to re-gather vital information interviewees might have forgotten to share, and also probably give them feed-back on the previous interviews.
(iii) Observation
Because people cannot always remember everything they do and the fact that they tend to act differently from their usual selves when they know they are being watched, there is need to independently verify information gotten from them through different methods. Observation is that technique of gathering information without the involved parties becoming aware of it. The Observer should make sure to be discrete, unpredictable and attentive to everything that happens regarding his subjects so that he can read trends which can be compared with information gathered through other sources.
(c) When choosing an information gathering technique, one should take into consideration
1. What type of information is being sought?
2. What is the gravity of the information being sought?
3. What is the scope of the information being sought?
4. Which technique can give corroborated information?
5. Is there need for users to be involved or they can circumvented?
6. What is the comparative cost in getting relevant information through the use of any given technique?
QUESTION 2
(a) What is UML?
It is the abbreviation for Unified Modelling Language. Since a model abstracts the essential details of the underlying problem from its usually complicated real world, it is necessary that there be a standard set of tools which can be used to organize/develop these models so as to allow many categories of people understand them.
Explain the use of the following diagrams:
(i) Use Case diagram:
They are UML diagrams that describe what a system does from the stand-point of an external observer. This is gotten from the fact that a use case, per se, is a summary of all the scenarios for a single task. It is made up of an actor (the user of the system), a use case (what the actor uses the system for) and an association (the actor’s relation to the use case). Thus a use case diagram is a collection of actors, use cases and their relative associations.
They are useful in that they, primarily, help in determining system requirements since new cases may elicit new system requirements as the diagram takes shape. They also aid communication between system developers and clients through the use of relatively simplified diagrammatic notation. Finally, they are useful in generating test cases in that the associated scenarios give a perfect collection of test cases for the system.
(ii) Class Diagrams:
A class diagram gives an overview of a system by showing its classes and the relationships among them. Class diagrams are static in that they display what interacts but not what happens when they do interact. This is from the background that a class is a template for merging attributes and behaviours into a single distinct entity, an object.
Friday, May 7, 2010
How IT can give your company competitive advantage
QUESTION
As an IT manager, advise your company on some of the top security issues and prepare a document to advise them on the benefits which can be achieved with the introduction of IT to create competitive advantage. Pick a case study area and base everything on it. Indicate the company and state what they do.
COMPANY PROFILE
PJEF Company Limited is a magazine printing and publishing company headquartered in Accra, with branches in Kumasi, Sunyani and Tamale. It has an online presence on the internet through their website where their publications can be perused and bought. This aspect is handled by the publishing and IT departments. It has a centralised authority structure. Though quite relatively modern, PJEF Co. Ltd uses off-the-shelf software, and an open internet system to network the different branches. Some very important documents are still kept on paper while the company puts no clear restriction on data access, especially within the proof reading department which happens to have developed a sort of departmental database which is at times utilised by the other departments. The Management board recently has tasked the IT department to identify some of the issues which adversely affect the efficient operation of the company. As the manager of the tasked department, the following are my findings
SECURITY RISKS AT PJEF CO. LTD.
As per the mandate of the Management Board, in my capacity as the IT manager of this company, I have carried out the authorised assessment of the operational IT risks of this company and the following form some of my major findings.
a. The use of only off-the-shelf software: As a printing and publishing company, PJEF cannot continue to rely on only off-the-shelf software to run its operations. So doing exposes the company to a lot of disadvantages such as making it easier for thieves to steal and pirate printing material. Again the absence of customised software such design software which is specifically written to suit the needs and operations of this company makes it very tedious for the design, typesetting and desktop publishing department to create a style which sets PJEF apart from other publishing houses.
b. Use of Open internet connectivity: Being a fast growing and quickly spreading company, PJEF cannot continue to use the open insecure internet as the means of networking its branches. The tendency for data loss/theft and corruption, not to mention the possibility of malicious attacks on PJEF corporate systems are real threats to the very operation of the company. Also, as a commercial entity which prides itself in quality work, it becomes a matter of competitive disadvantage while it does not speak well of the company to have in place no mechanism to protect the hard work of its valued clients, namely the signed authors.
c. On-site back-up: As a matter of great operational risk is the issue of on-site back-up. Currently, the IT department has no means of directly and simultaneously backing up all company data files off-site. The current system where data is backed up on site and later manually transferred to an off site location has a number of disadvantages such as the possibility of loss of limited but critical data and the possibility that due to human error may cause data not to be backed up at all, as indeed happened in the near fatal incident involving the PJEF and the author of a textbook. The current method of backing up leaves the company open to viral attack and data corruption since data transfer is manually handled.
d. Documentation of Important material on paper: The practice whereby the company still keeps important material on paper without making electronic copies could be very costly should there be a fire outbreak or even pest attack. While the practice of keeping such documents in a combination safe is quite laudable for keeping burglars at bay, it is quite insufficient to keep fire and other hazards out.
e. Poor database management: The Company has no database which makes it quite cumbersome when managing data inflow and access. The departmental database instituted by one of the departments is full of redundant data. The absence of an up-to-date database impedes managerial decision making, gives no clear picture of company performance and virtually creates a barrier between related departments.
f. Easy Access to Company Data: Going round with respect to finding out some of the security risks facing the company, I stumbled upon one very important issue, namely the easy nature in which data is accessed in this company. There appears to be no access restriction on some data, making such data easily accessible to almost everyone and thus vulnerable to theft, change or deletion. The practice whereby people can easily insert their personal external storage devices into the company computer system without having them scanned for viruses and then issued with clearances to use such secondary storage media could cause complete system failure should a very dangerous virus find its way into the company system.
The above are by no means the end of the list but they form the core of the security threats which the company faces. I will now go on to recommend ways in which the company can solve the problems enumerated above and thus increase its competitive advantage by introducing IT.
RECOMMENDATIONS
• The company should consider diversifying its operations by incorporating custom built and customised software into its computer systems. As a printing and publishing company which publishes both for the physical and online market, it gives the company some competitive edge when it does everything possible to produce products which are different from what everyone else in the business is producing. Since customised software is practically written to suit the preferred taste and operations of the one who orders it, unlike commercialised ones, it gives the company a very important tool to produce products which cannot be made anywhere else apart from PJEF.
• Though the company publishes on its internet website, it should consider using the many social network sites such as facebook, twitter, hi5, tagged, badoo, perfspot, myspace, etc. to increase awareness of its products and thus increase its customer base. When people on these sites are able to appreciate the good work which this company produces, the stage is set for us to take care of big printing orders which would arrive from almost every corner of the world. To add, the IT department should be resourced to help the relevant departments create a formidable online presence through serious online advertising campaigns.
But this should not draw away from the fact that the company needs to develop a better internal network purposely for coordination between the different branches. If this is done, data flow and sharing will be faster, safer and more reliable.
• As a matter of urgency, it is my recommendation that the company proceeds to make provisions for automated off-site back up of its data. This will forestall the loss, possible delays or corruption of company data. This will make the company appear more reliable to potential clients who would rest assured that their work will be finished on time any catastrophe notwithstanding.
• The company needs to immediately begin the process of converting into electronic format all important company documents. With current technology, documents which come in electronic formats are easier to store protect and transfer than their hardcopy counterparts. Watermarks can also be embedded within such documents as a seal of authenticity while they can be copy protected, write protected or even set to track changes made to it at what time. These attributes of the electronic file help the company to better protect its documents from corporate rivals.
• There needs to be an up-to-date database put in place with its requisite data access protocol. With the introduction of a regularly updated database, different departments within the company can have access to relevant data and hence increase efficiency and productivity, cutting down the time used to search for some particular data. Sensitive data will also be protected from unauthorised access leading to a generally confident working environment.
• Finally, the company should make it a policy not to allow personal secondary devices to be used on company computers except they have been scanned for any malicious software and after they have been used on the company computer if any company documents have been copied. In this quest, the system administrator should be vigilant in his work and flag any potential unauthorised system access and usage.
As an IT manager, advise your company on some of the top security issues and prepare a document to advise them on the benefits which can be achieved with the introduction of IT to create competitive advantage. Pick a case study area and base everything on it. Indicate the company and state what they do.
COMPANY PROFILE
PJEF Company Limited is a magazine printing and publishing company headquartered in Accra, with branches in Kumasi, Sunyani and Tamale. It has an online presence on the internet through their website where their publications can be perused and bought. This aspect is handled by the publishing and IT departments. It has a centralised authority structure. Though quite relatively modern, PJEF Co. Ltd uses off-the-shelf software, and an open internet system to network the different branches. Some very important documents are still kept on paper while the company puts no clear restriction on data access, especially within the proof reading department which happens to have developed a sort of departmental database which is at times utilised by the other departments. The Management board recently has tasked the IT department to identify some of the issues which adversely affect the efficient operation of the company. As the manager of the tasked department, the following are my findings
SECURITY RISKS AT PJEF CO. LTD.
As per the mandate of the Management Board, in my capacity as the IT manager of this company, I have carried out the authorised assessment of the operational IT risks of this company and the following form some of my major findings.
a. The use of only off-the-shelf software: As a printing and publishing company, PJEF cannot continue to rely on only off-the-shelf software to run its operations. So doing exposes the company to a lot of disadvantages such as making it easier for thieves to steal and pirate printing material. Again the absence of customised software such design software which is specifically written to suit the needs and operations of this company makes it very tedious for the design, typesetting and desktop publishing department to create a style which sets PJEF apart from other publishing houses.
b. Use of Open internet connectivity: Being a fast growing and quickly spreading company, PJEF cannot continue to use the open insecure internet as the means of networking its branches. The tendency for data loss/theft and corruption, not to mention the possibility of malicious attacks on PJEF corporate systems are real threats to the very operation of the company. Also, as a commercial entity which prides itself in quality work, it becomes a matter of competitive disadvantage while it does not speak well of the company to have in place no mechanism to protect the hard work of its valued clients, namely the signed authors.
c. On-site back-up: As a matter of great operational risk is the issue of on-site back-up. Currently, the IT department has no means of directly and simultaneously backing up all company data files off-site. The current system where data is backed up on site and later manually transferred to an off site location has a number of disadvantages such as the possibility of loss of limited but critical data and the possibility that due to human error may cause data not to be backed up at all, as indeed happened in the near fatal incident involving the PJEF and the author of a textbook. The current method of backing up leaves the company open to viral attack and data corruption since data transfer is manually handled.
d. Documentation of Important material on paper: The practice whereby the company still keeps important material on paper without making electronic copies could be very costly should there be a fire outbreak or even pest attack. While the practice of keeping such documents in a combination safe is quite laudable for keeping burglars at bay, it is quite insufficient to keep fire and other hazards out.
e. Poor database management: The Company has no database which makes it quite cumbersome when managing data inflow and access. The departmental database instituted by one of the departments is full of redundant data. The absence of an up-to-date database impedes managerial decision making, gives no clear picture of company performance and virtually creates a barrier between related departments.
f. Easy Access to Company Data: Going round with respect to finding out some of the security risks facing the company, I stumbled upon one very important issue, namely the easy nature in which data is accessed in this company. There appears to be no access restriction on some data, making such data easily accessible to almost everyone and thus vulnerable to theft, change or deletion. The practice whereby people can easily insert their personal external storage devices into the company computer system without having them scanned for viruses and then issued with clearances to use such secondary storage media could cause complete system failure should a very dangerous virus find its way into the company system.
The above are by no means the end of the list but they form the core of the security threats which the company faces. I will now go on to recommend ways in which the company can solve the problems enumerated above and thus increase its competitive advantage by introducing IT.
RECOMMENDATIONS
• The company should consider diversifying its operations by incorporating custom built and customised software into its computer systems. As a printing and publishing company which publishes both for the physical and online market, it gives the company some competitive edge when it does everything possible to produce products which are different from what everyone else in the business is producing. Since customised software is practically written to suit the preferred taste and operations of the one who orders it, unlike commercialised ones, it gives the company a very important tool to produce products which cannot be made anywhere else apart from PJEF.
• Though the company publishes on its internet website, it should consider using the many social network sites such as facebook, twitter, hi5, tagged, badoo, perfspot, myspace, etc. to increase awareness of its products and thus increase its customer base. When people on these sites are able to appreciate the good work which this company produces, the stage is set for us to take care of big printing orders which would arrive from almost every corner of the world. To add, the IT department should be resourced to help the relevant departments create a formidable online presence through serious online advertising campaigns.
But this should not draw away from the fact that the company needs to develop a better internal network purposely for coordination between the different branches. If this is done, data flow and sharing will be faster, safer and more reliable.
• As a matter of urgency, it is my recommendation that the company proceeds to make provisions for automated off-site back up of its data. This will forestall the loss, possible delays or corruption of company data. This will make the company appear more reliable to potential clients who would rest assured that their work will be finished on time any catastrophe notwithstanding.
• The company needs to immediately begin the process of converting into electronic format all important company documents. With current technology, documents which come in electronic formats are easier to store protect and transfer than their hardcopy counterparts. Watermarks can also be embedded within such documents as a seal of authenticity while they can be copy protected, write protected or even set to track changes made to it at what time. These attributes of the electronic file help the company to better protect its documents from corporate rivals.
• There needs to be an up-to-date database put in place with its requisite data access protocol. With the introduction of a regularly updated database, different departments within the company can have access to relevant data and hence increase efficiency and productivity, cutting down the time used to search for some particular data. Sensitive data will also be protected from unauthorised access leading to a generally confident working environment.
• Finally, the company should make it a policy not to allow personal secondary devices to be used on company computers except they have been scanned for any malicious software and after they have been used on the company computer if any company documents have been copied. In this quest, the system administrator should be vigilant in his work and flag any potential unauthorised system access and usage.
Thursday, March 4, 2010
types of OS
The computer industry, complicated and ever changing as it is, can boast of quite a number of Operating systems (OS), system software that enables communication between computer hardware and any other software that might be installed on the computer system. An OS type is defined by how it relates to the time factor, functionality (tasking), number of simultaneous users and level of manipulation. The above noted, we could speak of OS types such as
• Real-time Operating Systems
• Multi-user and Single user Operating systems
• Multi-tasking and single-tasking Operating systems
• Distributed Operated systems
• Embedded Operating system
It should however be noted that a particular OS may employ characteristics of two or more types of OS to maximise functionality and portability. At this point I would opt to write about multi-user operating systems.
A multi-user operating system ensures that more than one user operates the computer system at any one particular time. Resources of the computer system are so managed in a way that allows for speedy execution of operations by any one user in a way that gives an individual user the impression that he/she is the only one using the computer system at that particular time.
From the above, one is correct to bear in mind that for such an OS to work properly, the system must have good computing speed to ensure maximum computer time for each individual user, possess enough system memory to store the operations of each user, proper networking of the workstations involved (though some systems have done away with the use of workstations and instead operates using user accounts existing on the same system).
Use of a multi-user OS comes with a number of advantages such as reduction in hardware and software cost through shared resources, better system control through use of usernames and passwords that improves system security, though system breach becomes far more costly.
To end, it is worth mentioning that many of the popular operating systems available today are examples of multi-user OS. These include the Apple’s Mac OS, Microsoft’s Windows and almost all the UNIX distributions including Linux, Sun’s Solaris, etc.
BIBLIOGRAPHY
Slater, Robert, Portraits in Silicon, MIT Press, Cambridge, 1992.
http://www.computerhope.com/os.htm, 11-02-2010
http://wiki.answers.com/Q/What_are_the_four_types_of_operating_system_according_to_category, 11-02-2010
http://computer.howstuffworks.com/operating-system3.htm, 11-02-2010
• Real-time Operating Systems
• Multi-user and Single user Operating systems
• Multi-tasking and single-tasking Operating systems
• Distributed Operated systems
• Embedded Operating system
It should however be noted that a particular OS may employ characteristics of two or more types of OS to maximise functionality and portability. At this point I would opt to write about multi-user operating systems.
A multi-user operating system ensures that more than one user operates the computer system at any one particular time. Resources of the computer system are so managed in a way that allows for speedy execution of operations by any one user in a way that gives an individual user the impression that he/she is the only one using the computer system at that particular time.
From the above, one is correct to bear in mind that for such an OS to work properly, the system must have good computing speed to ensure maximum computer time for each individual user, possess enough system memory to store the operations of each user, proper networking of the workstations involved (though some systems have done away with the use of workstations and instead operates using user accounts existing on the same system).
Use of a multi-user OS comes with a number of advantages such as reduction in hardware and software cost through shared resources, better system control through use of usernames and passwords that improves system security, though system breach becomes far more costly.
To end, it is worth mentioning that many of the popular operating systems available today are examples of multi-user OS. These include the Apple’s Mac OS, Microsoft’s Windows and almost all the UNIX distributions including Linux, Sun’s Solaris, etc.
BIBLIOGRAPHY
Slater, Robert, Portraits in Silicon, MIT Press, Cambridge, 1992.
http://www.computerhope.com/os.htm, 11-02-2010
http://wiki.answers.com/Q/What_are_the_four_types_of_operating_system_according_to_category, 11-02-2010
http://computer.howstuffworks.com/operating-system3.htm, 11-02-2010
UNIX
Starting as a project by two Bell laboratories researchers, Dennis Ritchie and Kenneth Thompson, who simply wanted to make computing easier for themselves, the UNIX gradually became industry standard around the 1960s up till date. This was against the backdrop that the two researchers wanted an operating system that was easier, safer and user friendlier than Multics, the operating system which was being used at the time by Bell Laboratories. Though it never could topple Bill Gate’s MS-DOS and later Windows, it had by the 1980s become the most transported operating system used by large and middle-sized computers. Written in C, UNIX was developed by AT&T.
The UNIX OS can be said to have been a major player in the development of the internet due to its unique environment and server-client model. Its popularity also arose principally from the fact that it was freely distributed. Currently, many UNIX derivatives are distributed both freely and commercially.
Made up of the Kernel, file system and the command-line interface called the shell, UNIX boasts of more than 600 commands enabling users to manipulate data in any conceivable way. The above noted, UNIX has many advantages that makes it the best operating system to use.
Regarding cost, UNIX can be said to be very cost effective since it exists in both freeware and commercial distributions. This makes it better than the totally commercialised operating systems that exist today, for instance windows.
In matters of portability, none compares with the UNIX system. Because of the many distributions of different versions of UNIX, such as Linux (which also comes in many distributions) Sun’s Solaris, etc, one can easily use programs designed for one distribution in other distributions and not have to worry about efficiency. Currently, with the embedding of winetools in the source code of many UNIX distributions, many application software developed especially for the windows platform can now be used by UNIX users.
Because UNIX is freeware, it makes available source codes to people who intend to adapt them for personal use or in the name of education. This cannot be said for licensed OS like Windows which makes it a crime to edit its (window’s) source code. Because of that, one can always expect better output from the UNIX because there are so many people working to make it better to use.
Security is also better in a UNIX system than many other operating systems. Because of the compact layers of the UNIX kernel and the command-line Shell which requires that only the administrator with Super User (SU) privileges can change system parameters, it is very difficult to encounter security breaches from malware and unauthorised access.
Finally, it is worth noting that gone are the days when the UNIX shell scared a lot of people from using UNIX. Now with the incorporation of the motif GUI in many UNIX distributions, including Linux, it has become user friendly yet maintaining its security. No wonder the increasing popularity UNIX distributions, such as Linux, enjoy presently.
BIBLIOGRAPHY
Slater, Robert, Portraits in Silicon, The MIT Press, Cambridge, 1992.
http://en.wikipedia.org/wiki/Unix, 11-02-2010
http://www.unix.org/what_is_unix.html The Open Group, 28 December 2003, 11-02 -2010
http://www.unix.org/whitepapers/uos.pdf, the Open Group, 11-02-2010
The UNIX OS can be said to have been a major player in the development of the internet due to its unique environment and server-client model. Its popularity also arose principally from the fact that it was freely distributed. Currently, many UNIX derivatives are distributed both freely and commercially.
Made up of the Kernel, file system and the command-line interface called the shell, UNIX boasts of more than 600 commands enabling users to manipulate data in any conceivable way. The above noted, UNIX has many advantages that makes it the best operating system to use.
Regarding cost, UNIX can be said to be very cost effective since it exists in both freeware and commercial distributions. This makes it better than the totally commercialised operating systems that exist today, for instance windows.
In matters of portability, none compares with the UNIX system. Because of the many distributions of different versions of UNIX, such as Linux (which also comes in many distributions) Sun’s Solaris, etc, one can easily use programs designed for one distribution in other distributions and not have to worry about efficiency. Currently, with the embedding of winetools in the source code of many UNIX distributions, many application software developed especially for the windows platform can now be used by UNIX users.
Because UNIX is freeware, it makes available source codes to people who intend to adapt them for personal use or in the name of education. This cannot be said for licensed OS like Windows which makes it a crime to edit its (window’s) source code. Because of that, one can always expect better output from the UNIX because there are so many people working to make it better to use.
Security is also better in a UNIX system than many other operating systems. Because of the compact layers of the UNIX kernel and the command-line Shell which requires that only the administrator with Super User (SU) privileges can change system parameters, it is very difficult to encounter security breaches from malware and unauthorised access.
Finally, it is worth noting that gone are the days when the UNIX shell scared a lot of people from using UNIX. Now with the incorporation of the motif GUI in many UNIX distributions, including Linux, it has become user friendly yet maintaining its security. No wonder the increasing popularity UNIX distributions, such as Linux, enjoy presently.
BIBLIOGRAPHY
Slater, Robert, Portraits in Silicon, The MIT Press, Cambridge, 1992.
http://en.wikipedia.org/wiki/Unix, 11-02-2010
http://www.unix.org/what_is_unix.html The Open Group, 28 December 2003, 11-02 -2010
http://www.unix.org/whitepapers/uos.pdf, the Open Group, 11-02-2010
of Hobbes and Quarrels
Q3: Discuss the principal causes of quarrel in every society as proposed by Thomas Hobbes
Thomas Hobbes is of the view that man is exclusively selfish in all his actions and is not likely to perform any action if such an action will be of no benefit to him. It is on this premise that Hobbes begins his discussion on the causes of quarrel in the human society.
It is worth noting that in Hobbes’ view, there is in practice nothing which is objectively good or bad, but that there are only things which a person desires and that which he averts, representing good and bad, respectively.
Moving on to the causes of quarrel, Hobbes gives three main reasons why there is conflict in society, namely competition, diffidence and glory. But it worth noting that the proper context where the three causes promote conflict is found in Hobbes’ psychological theory where he states that
a. the individual is psychologically selfish,
b. the individual’s greatest desire is self preservation
c. the individual’s greatest aversion is death.
Again it is worth considering the two laws of nature (namely seeking peace in order to follow it and defending oneself by all means) and how they affect the individual’s desire for self-preservation and his aversion of death.
Considering competition as a cause of quarrel, Hobbes makes it known that nature has made all people equal in the powers they need to exist. But there is the selfish inclination within man to try to maximize his happiness, which is nothing else than the level of success one has in self-preservation. Hence he invades others for gain, leading to quarrel.
For reasons of safety, an individual may be forced to confront others. This is called diffidence. Should any threat, imagined or real, arise to cause fear in an individual’s desire to maximize his happiness, he is forced to counter that threat through any means necessary, hence quarrel with the object of his aversion.
Finally, because of man’s selfishness, he tries to assert himself over others. He thus looks for means to achieve glory which is nothing else but quest for reputation. When and individual does not wish to remain on equal terms with others, he resorts to all manner of actions to assert himself over them. Thus glory becomes a cause of quarrel taking into account that man is naturally selfish.
In conclusion, without the presence of a sovereign who would provide the needed balance to every individual’s desire, the probability is high that every person will quarrel with his neighbour, given that confrontations may arise out of desire for self preservation, aversion to fear in favour of safety or to seek glory.
Thomas Hobbes is of the view that man is exclusively selfish in all his actions and is not likely to perform any action if such an action will be of no benefit to him. It is on this premise that Hobbes begins his discussion on the causes of quarrel in the human society.
It is worth noting that in Hobbes’ view, there is in practice nothing which is objectively good or bad, but that there are only things which a person desires and that which he averts, representing good and bad, respectively.
Moving on to the causes of quarrel, Hobbes gives three main reasons why there is conflict in society, namely competition, diffidence and glory. But it worth noting that the proper context where the three causes promote conflict is found in Hobbes’ psychological theory where he states that
a. the individual is psychologically selfish,
b. the individual’s greatest desire is self preservation
c. the individual’s greatest aversion is death.
Again it is worth considering the two laws of nature (namely seeking peace in order to follow it and defending oneself by all means) and how they affect the individual’s desire for self-preservation and his aversion of death.
Considering competition as a cause of quarrel, Hobbes makes it known that nature has made all people equal in the powers they need to exist. But there is the selfish inclination within man to try to maximize his happiness, which is nothing else than the level of success one has in self-preservation. Hence he invades others for gain, leading to quarrel.
For reasons of safety, an individual may be forced to confront others. This is called diffidence. Should any threat, imagined or real, arise to cause fear in an individual’s desire to maximize his happiness, he is forced to counter that threat through any means necessary, hence quarrel with the object of his aversion.
Finally, because of man’s selfishness, he tries to assert himself over others. He thus looks for means to achieve glory which is nothing else but quest for reputation. When and individual does not wish to remain on equal terms with others, he resorts to all manner of actions to assert himself over them. Thus glory becomes a cause of quarrel taking into account that man is naturally selfish.
In conclusion, without the presence of a sovereign who would provide the needed balance to every individual’s desire, the probability is high that every person will quarrel with his neighbour, given that confrontations may arise out of desire for self preservation, aversion to fear in favour of safety or to seek glory.
of pure silicon and diodes
- Pure silicon is not a conductor because in its pure state its electrons are bonded tightly with the electrons of other neighbouring silicon atoms in such a way that it requires a relatively large increase in energy levels to cause electrons to break from the valence band into the conduction band.
- When silicon is doped with phosphorus, the result would be that an excess of one electron is created on the valence band of the doped silicon atom. Since the valence band of an atom takes up to eight (8) electrons, there would exist one free moving electron which can easily jump into the conduction band, thus constituting flow of electrical current.
- The main difference between a P-type silicon and an N-type silicon exists in what material was used to dope the silicon. Should the silicon undergo a Trivalent doping, using an element with a valence band consisting of 3 electrons (eg boron) there would exist one empty spot on the shell after the two elements are bonded thus leading to the formation of a P-type silicon. It is P-type (positive) because it lacks one more electron to complete its valence band.
A diode, being a device which allows electric current to flow in one direction is made up of a P-type and an N-type silicon arranged adjacent each other, leaving a thin film of space called the depletion region connected to an energy source. It is in the arrangement of the energy source in the circuit which dictates in which direction current flows.
In a forward biased diode, there exists a positive voltage across the diode from the P to N type silicon. This enables the diode to act like a good conductor hence allowing current to flow in one direction.
However, when the polarity in the energy source is changed so that there is almost no flow of current then one has a reverse-biased diode. This causes the diode to become almost non-conducting and measures a large amount of voltage across the devise.
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