Phases Of System Development Life Cycle Information Technology Essay

Phases Of System Development Life Cycle Information Technology Essay System development life cycle means combination of various activities. In other words we can say that various activities put together are referred as system development life cycle. In the System Analysis and Design terminology, the system development life cycle means software development life cycle. Following are the different phases of software development cycle: System study Feasibility study System analysis System design Coding Testing Implementation Maintenance   The different phases of software development life cycle is shown in Fig.29.1 Different phases of Software development Life Cycle PHASES OF SYSTEM DEVELOPMENT LIFE CYCLE Let us now describe the different phases and the related activities of system development life cycle in detail. (a) System Study System study is the first stage of system development life cycle. This gives a clear picture of what actually the physical system is? In practice, the system study is done in two phases. In the first phase, the preliminary survey of the system is done which helps in identifying the scope of the system. The second phase of the system study is more detailed and in-depth study in which the identification of users requirement and the limitations and problems of the present system are studied. After completing the system study, a system proposal is prepared by the System Analyst (who studies the system) and placed before the user. The proposed system contains the findings of the present system and recommendations to overcome the limitations and problems of the present system in the light of the users requirements. To describe the system study phase more analytically, we would say that system study phase passes through the following steps: problem identification and project initiation background analysis inference or findings (b) Feasibility Study On the basis of result of the initial study, feasibility study takes place. The feasibility study is basically the test of the proposed system in the light of its workability, meeting users requirements, effective use of resources and .of course, the cost effectiveness. The main goal of feasibility study is not to solve the problem but to achieve the scope. In the process of feasibility study, the cost and benefits are estimated with greater accuracy. (c) System Analysis Assuming that a new system is to be developed, the next phase is system analysis. Analysis involved a detailed study of the current system, leading to specifications of a new system. Analysis is a detailed study of various operations performed by a system and their relationships within and outside the system. During analysis, data are collected on the available files, decision points and transactions handled by the present system. Interviews, on-site observation and questionnaire are the tools used for system analysis. Using the following steps it becomes easy to draw the exact boundary of the new system under consideration: Keeping in view the problems and new requirements Workout the pros and cons including new areas of the system All procedures, requirements must be analyzed and documented in the form of detailed data flow diagrams (DFDs), data dictionary, logical data structures and miniature specifications. System Analysis also includes sub-dividing of complex process involving the entire system, identification of data store and manual processes. The main points to be discussed in system analysis are: Specification of what the new system is to accomplish based on the user requirements. Functional hierarchy showing the functions to be performed by the new system and their relationship with each other. Function network which are similar to function hierarchy but they highlight those functions which are common to more than one procedure. List of attributes of the entities these are the data items which need to be held about each entity (record) (d) System Design Based on the user requirements and the detailed analysis of a new system, the new system must be designed. This is the phase of system designing. It is a most crucial phase in the development of a system. Normally, the design proceeds in two stages: preliminary or general design Structure or detailed design Preliminary or general design: In the preliminary or general design, the features of the new system are specified. The costs of implementing these features and the benefits to be derived are estimated. If the project is still considered to be feasible, we move to the detailed design stage. Structure or Detailed design: In the detailed design stage, computer oriented work begins in earnest. At this stage, the design of the system becomes more structured. Structure design is a blue print of a computer system solution to a given problem having the same components and inter-relationship among the same components as the original problem. Input, output and processing specifications are drawn up in detail. In the design stage, the programming language and the platform in which the new system will run are also decided. There are several tools and techniques used for designing. These tools and techniques are: Flowchart Data flow diagram (DFDs) Data dictionary Structured English Decision table Decision tree (e) Coding After designing the new system, the whole system is required to be converted into computer understanding language. Coding the new system into computer programming language does this. It is an important stage where the defined procedures are transformed into control specifications by the help of a computer language. This is also called the programming phase in which the programmer converts the program specifications into computer instructions, which we refer as programs. The programs coordinate the data movements and control the entire process in a system. It is generally felt that the programs must be modular in nature. This helps in fast development, maintenance and future change, if required. (f) Testing Before actually implementing the new system into operations, a test run of the system is done removing all the bugs, if any. It is an important phase of a successful system. After codifying the whole programs of the system, a test plan should be developed and run on a given set of test data. The output of the test run should match the expected results. Using the test data following test run are carried out: Unit test System test Unit test: When the programs have been coded and compiled and brought to working conditions, they must be individually tested with the prepared test data. Any undesirable happening must be noted and debugged (error corrections). System Test: After carrying out the unit test for each of the programs of the system and when errors are removed, then system test is done. At this stage the test is done on actual data. The complete system is executed on the actual data. At each stage of the execution, the results or output of the system is analyzed. During the result analysis, it may be found that the outputs are not matching the expected out of the system. In such case, the errors in the particular programs are identified and are fixed and further tested for the expected output. When it is ensured that the system is running error-free, the users are called with their own actual data so that the system could be shown running as per their requirements. (g) Implementation After having the user acceptance of the new system developed, the implementation phase begins. Implementation is the stage of a project during which theory is turned into practice. During this phase, all the programs of the system are loaded onto the users computer. After loading the system, training of the users starts. Main topics of such type of training are: How to execute the package How to enter the data How to process the data (processing details) How to take out the reports After the users are trained about the computerized system, manual working has to shift from manual to computerized working. The following two strategies are followed for running the system: Parallel run: In such run for a certain defined period, both the systems i.e. computerized and manual are executed in parallel. This strategy is helpful because of the following: Manual results can be compared with the results of the computerized system. Failure of the computerized system at the early stage, does not affect the working of the organization, because the manual system continues to work, as it used to do. Pilot run: In this type of run, the new system is installed in parts. Some part of the new system is installed first and executed successfully for considerable time period. When the results are found satisfactory then only other parts are implemented. This strategy builds the confidence and the errors are traced easily. (h) Maintenance Maintenance is necessary to eliminate errors in the system during its working life and to tune the system to any variations in its working environment. It has been seen that there are always some errors found in the system that must be noted and corrected. It also means the review of the system from time to time. The review of the system is done for: knowing the full capabilities of the system knowing the required changes or the additional requirements studying the performance If a major change to a system is needed, a new project may have to be set up to carry out the change. The new project will then proceed through all the above life cycle phases. Task: 4.2 Life Cycle Models Waterfall model Prototyping model Evolutionary model The spiral model Formal development Incremental development Rapid application model V-Shaped model Requirements analysis Definition Integration and Software testing Software dDesign Implementation and unit testing Operation and Maintenance Waterfall Model Figure: 7 This takes the fundamentals process activities of specification, development, validation and evolution and represents them as separate process phase such as requirement specification, software design, implementation and testing and so on. Requirement Analysis and Definition The systems services, constraints and goals are established by consultation with the software users. They are then defined in detail and serve as a software specification. how the current software works and what it does Producing a detailed model in subject terms of what the new software will do and how it will work. Producing a high-level description of new software Software Design The software design process partitions the requirements to either hardware or software system. It establishes overall software architecture. Software design involves identifying and describing the fundamental software system abstraction and their relationships. Implementation and Unit Testing During this stage, the software design is realized as a set of programs or program units. Unit testing involves verifying that each unit meets its specification. Integration and Software Testing The individual program units or programs are integrated and tested as complete software to ensure that the software requirements have been met. After testing, the software system is delivered to the customer. Operation and Maintenance Normally this is the longest life cycle phase. The software is installed and put into practical use. Maintenance involves correcting errors which were not discovered in earlier stages of the life cycle; improving the implementation of the software units and enhancing the softwares services as new requirement are discovered.

Cyrus the Shepherd

Sorie Kargbo AP World 1A 10-9-12 In  Persia  Ã¢â‚¬Å"Cyrus  the Shepherd† invited a newer, more sophisticated government that distinguished it from the previous foundation civilization. In this new government, a centralized bureaucracy ruled, meaning that while Cyrus was the king and Persepolis was the capital a highly staffed team helped run the empire. Since the Persian Empire was so large, Cyrus broke it up into many distinct sections called satraps, which had considerable local autonomy (power).In other words, not only was there a strong central government but there was also bureaucrats who helped rule and maintain order in provinces throughout the empire. The Persian Empire, in addition, was very diverse, containing many different religions and ethnicities. Overall, the Persian Emperors were very tolerant and respected all peoples. The big religion you should know, however, is Zoroastrianism. Many historians consider this the first Monotheistic faith.Technologically, the Persians had Qantas which were sophisticated irrigation dams. Of course, metallurgy was still an integral part of technological life. In China, as you may know, the foundations period ended with the fall of the Zhou Dynasty and the commencement of Warring States Period, a time of great strife and civil war in China. Finally, however, the  Qin Dynasty  gained power. Qin Huangde (sp) was the emperor of the Qin and he was very, very power-hungry and intolerant.He made his people complete many public works project, pay high taxes, and he even ordered the burnings of thousands of books. If someone disagreed with him, they would die – no questions asked! Of course, not all bad came out of this period. First of all, the Qin Dynasty marked the return to stable rule after centuries of ravaging civil war. Also, magnificent structures like The Great Wall of China were commenced at this time. Later, after the fall of the Qin (which only lasted 10 years due to peasant unrest †“ I wonder why†¦.. the Han Dynasty took over. The Han was much more similar to the Persians. It was centralized and bureaucratic. One important distinction, however, is that the leaders practiced Confucianism and had to pass a civil-service examination to serve as a government leader. While religion formed the backbone of culture in Persia, Confucianism was the cultural hallmark of China. Like Persia, China used progressively more advanced irrigation techniques to stop the flooding of the Yellow River and metallurgy

The painting A Jeu de Paume Before a Country Palace

Adriaen van de Venne `s painting   A Jeu de Paume Before a Country Palace: An AnalysisThe painting A Jeu de Paume Before a Country Palace is a small painting by the Dutch artist Adriaen van de Venne.   The beauty of this painting is spectacular.   The picture presented is busy with many people in the depiction as well as many activities.At first the eye is drawn to the palace.   Even though it is in the country, it is ornate and impressive with its spires and cupolas.   Faded into the background is the image of a silhouette of a village.   The sky is littered with birds, and dogs dominate the crowd scene.Bordered by an elegant fountain and garden on one side and a forest with goats and deer on the other, there is a game of ball taking place.   Many people of all classes and backgrounds are entertained by watching the game.   In the left hand corner there are lovers who are oblivious to the rest of the excitement.   The one character that stands out is the middle age d, hefty man in the front who is dressed as a country gentleman.   There is a sense of frivolity in the mood of this painting.  A Jeu de Paume Before a Country Palace was painted in sixteen fourteen.   The oil on panel is six and one half by nine inches.   This painting and its companion, A Merry Company in an Arbor, were part of a series of four landscapes representing the seasons. This painting probably represents summer. (A Jeu de Paume Before a Country Palace)   The painter, Adriaen van de Venne, was born in 1589 in Delft, Netherlands, and died in 1662in The Hague, Netherlands.

Othello Character Analysis - 1378 Words

William Shakespeare’s play â€Å"Othello† like most of his plays is about the premature death of a character who may or may not be considered a tragic hero. Othello, the Moor of Venice, follows him, his wife Desdemona, Cassio, and the main protagonist Iago through a series of unfortunate events that are supposed to be about jealousy between coveting a boss’s wife and a job promotion. The story turns to Iago when he turns into a commanding force that dishevels every character in the play. This is all done through the a simple fact that Iago is consisted an honest man and honest men would not do something so devious. Just by Iago talking Iago changes the tone of the whole scene. With Iago’s plot to destroy Othello just by being his friend and†¦show more content†¦While Othello is in this questioning state towards Desdemona’s honesty and integrity, Iago makes certain claims knowing it would set off Othello’s jealousy and paranoia spec ifically focusing on the relationship between his wife and Cassio. Phrases like â€Å"Did Michael Cassio, When you wooed my lady, know of your love?† is the start to Othello searching for suspicious action from Cassio in past events that did not occur( 3.3 105). His use of repetition makes Othello think and creates problems or negative thoughts where there were none before â€Å"Think, my lord?† By heaven, thou echo’st me As if there were some monster in thy thought Too hideous to be shown. Thou dost mean something† (3.3.121-124). Iago’s use of Desdemona’s handkerchief turns Othello’s conceptual paranoia into a more physical entity. Even though it is known the audience that there is no affair between Desdemona and Cassio the lost handkerchief provides tactile evidence to Othello allows Iago’s false accusations to become true â€Å"I have use for it. Go, leave me. I will in Cassio’s lodging lose this napkin And let him find it. Trifles light as air Are to the jealous confirmations strong As proofs of holy writ† (3.3.369-373). Because Iago disrupted Othello’s thoughts of his wife Desdemona, his friend Cassio, and his marriage with the use of paranoia, uncertainty, and jealousy, Othello’s behavior from this point on will be more erratic he even says â€Å"now, forever FarewellShow MoreRelatedOthello Character Analysis1555 Words   |  7 Pagesinherent weakness lies in his linguistic capabilities, the very same capabilities Othello uses to win over Desdemona, and to defend himself during his trial in front of the duke. In Smith’s reading, Othello only reverts to his barbarian state when experiencing extreme pressure, as he lacks the other means to express the futility of what is felt, which results in violence. However, when a closer look is taken at what Othello knows about the culture he has tried to hard to assimilate to, it can be seenRead More Character Analysis of Othello Essay1653 Words   |  7 PagesCharacter Analysis of Othello â€Å"Othello† is a tragedy and Othello is a tragic hero. Othello is a general in the service of Venice. He is good, courageous, brave and trustworthy. However he has some weaknesses such as insecurity; he is too open, naà ¯ve, and gullible, Iago plays on his weaknesses which brings about his downfall and he kills himself. This causes the suffering of innocent people like Desdemona, Emilia, Cassio and Roderigo. The audience also feel pity forRead MoreCharacter Analysis Of Othello1235 Words   |  5 PagesOthello is not just about one tragedy but several tragedies of suffering and injustice. The play ends in fatalities and heartbreak from the consequences of jealousy and racism. Othello is a well-respected military man who does not let race stand in the way of earning his reputable status and attention of beautiful Desdemona. But, when the seed of jealous is planted, Othello becomes easily manipulated into believing false accusations because of his own personal insecurities. He becomes a menace toRead MoreOthello Character Analysis1076 Words   |  5 PagesThe Mediterranean Sea of Jealousy Harriet Williams delves into the waters of jealousy and deceit in Oliver Parker’s Othello. Adapting Shakespeare for the screen can be problematic, as Oliver Parker discovered with his 1995 directing debut, Othello. I sat down with Oliver Parker, to discuss the challenge of portraying the actions of a noble Moor who brutally sacrifices his beloved wife over a strategically placed handkerchief. The characterisation of Iago, whose evil maneuverings create an irrevocableRead MoreOthello Character Analysis Essay801 Words   |  4 Pages12/12/2017 A Character Analysis of Othello in William Shakespeare’s â€Å"Othello† The main character, Othello, in the Shakespearean play Othello, is a man of many strengths, but also a man of great weakness. The play is center around Othello’s downfall despite Shakespeare presenting him as a distinguished and respected soldier. He is also depicted as courageous and loving to his wife Desdemona. However, Othello starts to show his insecurities and weaknesses during the play. Indeed, Othello becomes a belligerentRead MoreCharacter Analysis : Othello 1255 Words   |  6 PagesPavle Burazor Ms. Ã…  kiljević ENG3U1 06-Jan-2015 Character Flaws in Othello The play Othello bears great similarity to that of the Greek myth of Sisyphus, the king of Ephyra; where Sisyphus was sentenced to forever push a boulder up a hill. This makes resemblances the climb to a climax and the fall, with three main characters, each pushing a boulder up a hill; Othello one of trust, Iago one of manipulation and Roderigo pushing one of foolishness. When they finally reach the top of the hill it beginsRead MoreOthello Character Analysis1562 Words   |  7 PagesCompare the roles and functions of the female characters in Othello. Othello by William Shakespeare is set in 16th century Renaissance Venice before transitioning to the island of Cyprus. It follows the relationship between the black Venetian general and â€Å"valiant Moor† Othello and his new wife Desdemona, the daughter of an important Venetian senator. Throughout the play, we encounter three main female characters; Cassio’s mistress Bianca, Othello’s wife Desdemona as well as her maid and Iago wifeRead MoreOthello Character Analysis905 Words   |  4 Pages1. Throughout the drama, â€Å"The Tragedy of Othello†, Iago successfully manipulates Cassio various times. In the writing, Shakespeare creates Iago’s plan to demote Cassio from being Othello’s lieutenant, the role Iago dreamt of, by tricking Cassio to get drunk so that he will raise chaos and result in Cassio being demoted. This worked out for Iago when Cassio accepts Iago’s encouraging words and began to drink heavily, this would result in Cas sio ultimately fighting and stabbing Montano in a drunkenRead MoreOthello Character Analysis1241 Words   |  5 PagesOthello, a play written in the setting of Venice City during a period of war between Venice and Turkey in the 16 century is one of the numerous William Shakespeare’s plays. Othello a middle-aged black moor who is also a general in the defense forces marries Desdemona, a white aristocratic lady against the wishes of her father. Their love, however, does not have the happily ever after ending due to the manipulations, deceptions, and scheming of Iago who is driven by revenge and selfish ambitions.Read MoreOthello Character Analysis863 Words   |  4 Pagesis being harmful or tending to harm. In the novel Othello, by Shakespeare, character Iago is presented as a villain who doesn’t respect moral beauty, nor the grand nobleness of the mighty souled Othello. Iago betrays Othello knowing how strong Othello’s trust is towards him. As you keep reading the novel you notice the cruelty Iago has for his wife Emilia and how his plan of getting Othello jealous caused the deaths of his own wife Emilia, Othello and Desdemona. Iago is a man full selfishness