Antigone Tragic Hero essays

Antigone Tragic Hero essays In the novel Antigone Sophocles, the author, depicts the tragic hero Creon to the fullest extent. Sophocles portrays Creon as a tragic hero by the characteristics shown throughout the story. Creon is a character that is easy to relate to in a number of ways. First, he contains many flaws which in result causes many problems. This is seen in the decision he made of becoming hubris. Hubris is a Greek term for insolence and is referred to the emotions in Greek tragic heroes and ignores the gods and thus invite catastrophe. Catastrophe is all Creon got as the novel progressed into the climax. His choices and decisions end up deciding the fates of his son, wife, and Antigone. After having an encounter however with Teiresias, Creon comes around to realize what he has done is sinful to the gods. He has put his own pride over the fact of appreciating the gods. The character Creon may not be seen as a tragic hero because of his tasteless acts, but he contains the traits eligible to be the tra gic hero in Antigone. As seen in the novel, Creon exhibits habits seen in todays life, even though Sophocles wrote this novel a long time ago. It is obvious that Creon displays an immense amount of stubbornness throughout the story. An example is seen when Antigone wishes to give her brother, Polynieces a proper burial so he can go and be with the Gods. Creon as king wishes to have him rot in the fields of war because he disowned the state in the war that preceded the events. Antigone fights for her beliefs of the divine law that one should always receive a proper burial after death, but Creon refuses and throws Antigone in jail. His stubbornness is seen here in this quote, Go join them, then: if you must have your love, find it in hell!(pg286). As seen in the quote, even after Antigone clearly makes sense in what she was doing, and the prophet also agrees with her, Creon turns to the ...

Hysteron Proteron - Definition and Examples of the Figure of Speech

Hysteron Proteron s of the Figure of Speech A figure of speech in which the natural or conventional order of words, actions, or ideas is reversed. Hysteron proteron is generally regarded as a type of hyperbaton. The figure of hysteron proteron has also been called inverted order or putting the cart before the horse.  Eighteenth-century lexicographer Nathan Bailey defined the figure as a preposterous way of speaking, putting that first which should be last.  Hysteron proteron most often involves inverted syntax  and is used primarily for emphasis. However, the term has also been applied to inversions of narrative  events in nonlinear plots: that is, what happens earlier in time is presented later in the text.   Etymology From the Greek hysteros  and  proteros , latter first Examples and Observations He began to walk barefoot across the meadow, but the sharp dry grass hurt his feet. He sat down to put on his shoes and socks.(Iris Murdoch, Nuns and Soldiers, 1980)That time of year thou mayst in me beholdWhen yellow leaves, or none, or few do hang ...(William Shakespeare, Sonnet 73)Muammar Gaddafi Killed, Captured In Sirte(Headline in Huffington Post, Oct. 20, 2011)Im going to kill that magician. Ill dismember him and then Ill sue him.(Woody Allen, Oedipus Wrecks in New York Stories, 1989) Yoda-Speak One of the most common and effective forms of hyperbaton is  hysteron proteron  (roughly, last things first). Let’s take two examples from a master of the technique: Powerful you have become. The Dark Side I sense in you and Patience you must have, my young padawan. For Yoda in  Star Wars, hysteron proteron is a linguistic trademark. The key concepts in those three sentences are power, the Dark Side and patience. Their placement underlines them.   (Sam Leith, Much to Learn From Yoda, Public Speakers Still Have. Financial Times [UK], June 10, 2015) Hysteron Proteron in Don DeLillos Cosmopolis (2003) So attuned is [Eric] Packer to the future that he repeatedly literalizes the rhetorical trope known as hysteron proteron; that is, as he scans the several digital monitors mounted in his limousine, he experiences an effect before its cause. Among Packers premonitions is observing himself onscreen recoiling in shock from the Nasdaq bombing before the actual blast occurs.   (Joseph M. Conte, Writing Amid the Ruins: 9/11 and Cosmopolis. The Cambridge Companion to Don DeLillo, ed. by John N. Duvall. Cambridge University Press, 2008) Puttenham on Hysteron Proteron (16th century) Ye have another manner of disordered speech, when ye misplace your words or clauses, and set that before which should be behind. We call it in English proverb, the cart before the horse, the Greeks call it Histeron proteron, we name it the Preposterous, and if be not too much used is tolerable enough, and many times scarce perceivable, unless the sense be thereby made very absurd.   (George Puttenham, The Arte of English Poesie, 1589) Hysteron Proteron in Rhetoric and in Logic Hysteron proteron was thus a term from the discourse of rhetoric for a reversion that reversed the order of things themselves, including in both temporal and logical sequence. In this sense, it appeared across a broad range of early-modern writing, as both a blemish and an exploited license of order and style...In the field of formal logic, hysteron proteron simultaneously denoted a preposterous inversion, in this case the logical fallacy of assuming as true and using as a premise a proposition that is yet to be proved, or the proving of a proposition by reference to another one that presupposes it.(Patricia Parker, Hysteron Proteron: Or the Presposterous, in Renaissance Figures of Speech, ed. by Sylvia Adamson, et al., Cambridge University Press, 2007) Pronunciation: HIST-eh-ron PROT-eh-ron

1) Unit of work for listening and speaking skills for ESL primary Essay

1) Unit of work for listening and speaking skills for ESL primary Enlish classroom. 2) An stating the rationale, theoretical principles, reflection for th - Essay Example Not all aspects of the text chat and face-to-face environments are similar. In text chat, it is possible for several participants to participate simultaneously. This unit is designed for the pupils of primary level around the age of 10 years. This unit contains some dialogues, narratives and some interesting and absorbing exercises for enhancing listening and speaking capabilities of pupils. The topic of unit is quite interesting. The unit revolves round the unlucky Friday 13th. It focuses on the superstitious aspect of western culture. The topic of unit not teaches language skills but it also introduces non-native pupils to the culture of the western society. The unit theme is quite absorbing and motivating. Pupils would automatically try to speak about the unfortunate incidents took place in the life Emily on that unlucky Friday. A lesson plan is a comprehensive and predetermined schedule of every activity of teacher in classroom for achieving optimal results. A lesson plan can be of many forms and types. It usually depends on time span, style of educator and type of subject to be taught. But the basic and main objective of any type of lesson plan is to provide teacher a pre-planned line of action for presenting materials and interacting with learners. The lesson plan should not be merely a action plan but it should provide a useful link between objectives of curriculum and material to be taught. Motivate students by telling them about the poor Emily who faced lot of hardships on unlucky Friday. Tell the students background of Friday 13th that is considered unlucky. Tell them how much hardships she faced on that particular day but how boldly she faced them. Encourage students to be bold if such situation may arise in their daily routine. It will create intimacy with the character. Tell the students the how important is listening for correct speaking. Tell them

A Farewell to Modernism Essay Example | Topics and Well Written Essays - 500 words

A Farewell to Modernism - Essay Example The researcher of this essay "Modernism of Art" aims to explore the work of Jack Ryan in the context of modernism. Castelli is more remembered as one of the core founders of modern art and contributed a lot in nurturing young talents that enhanced modernism of art. Jack Ryan has for years perfected his art in creating unique modern. In looking at Jack Ryan’s work, one could appreciate the effect modernism of art has on the observers. For instance, the picture is one could clearly marvel at his work and appreciate how modernism has taken toll of the market. In today’s world, many artists have started relying on the use of media like the internet to market their art works. Jack Ryan is an excellent example of an artist practicing modernism in art through inclusion of objects or art work associated with the modern age. For instance, the picture provides an iconic feeling of sophistication. He uses random numbers on the upper part of his art work making one to think of what he intended to convey. Furthermore, it results to confusion when he the picture conveys a number of cubic drawings which drawings that resemble speakers. The object provides a feeling of an amorphous creation which no one is able to understand, which is, out of the blue drawing. It is an original work since no one has ever seen such a creation in the normal. Such a drawing creates a deep sense of anxiety and wondering what the artists could have thought or implied to convey while making such an iconic art piece.

Conspiracy Theories Explained

Conspiracy Theories Explained Introduction â€Å"Conspiracy theory† is a subject that awakens our sense of interest and curiosity. Knowing that what we are told may not be true, makes us want to know more about that subject and, sometimes, any other theory that comfort us, seems more legit. These theories are like a darker side of some huge events, that the government and/or other secret facilities want to hide from the society, and the society tends to be suspicious, leading to an uncertainty about the official statements. This subject is very exciting for our group because it’s something that makes us curious and it has to do with our possible future job as part of the media. We also chose this theme because we think it’s a very good way to develop the interest of our school mates, to be more curious and develop their sense of investigation. A person who’s curious about something like theories of conspiracy is a person that is curious about everything and that’s very important in social communication students like us. Furthermore, curiosity has always been one of the most important characteristic of human beings, because if we weren’t curious, we wouldn’t have discovered how to make fire yet. Ana Rita Rebelo What are Conspiracy Theories and why do people tend to believe them? The word â€Å"conspiracy† comes from Latin, con (with) and spirare (breathe). By joining â€Å"breathing† and â€Å"with†, we get whispering, which presuppose a secret. So, conspiracy is a group of people who act in secret. Conspiracy theories are non-proven alternative explanations for facts or events, usually created by someone or a group who has an opinion that goes against the official version of the same episode. The creators and fans of those theories that are supported and confirmed by respectable institutions or highly credible people, are usually sceptics about the explanations that is given to the society, so they come up with theories that reveal an â€Å"alleged secret plan, led by a secret alliance of powerful organizations and individuals† (Freedman 2000)[1]. The majority of people, who believe on these kinds of theories, have lost their faith in politics, or on the hierarchical power that rules the country. Those leaders in charge are considered to be double-crossers and ruthless people, so any official explanations that come from them are immediately declined or causes a lot of uncertainty within society. This leads to an increased reliability in any other unofficial explanation. Other common feature in believers of conspiracy theories is fear. If, for example, it had occurred a terrorist attack or a natural disaster, we would feel powerless and panicking, so we would more easily believe in any theory that can comfort us, even if it goes against the official explanation and if it can’t be proved. Ana Rita Rebelo How do people create theories of conspiracy? 1- Define your Conspiracy subject matter Choosesomething people find puzzling,conspiracy theories develop where people are mystified, confused and curious. People have the in need to feel that there is sense in what happens in the world, thats why when we dont understand them we’ll make a story/theory for why events happen. 2 Make sure what you choose to explain is significant to enough readers. If your subject isnt significant to other people they wont even give you the time to explain your theory cause theyre not into it, so if you want your theory to spread, be known and have followers/supporters youll have to choose an interesting subject, not just for you bur for others, something with a big impact in society and the world. 3 Identify the agents responsible for the Conspiracy You always have to find someone to put the blame on, normally people dont easily accept the fact that things happened because it was supposed to, like when a natural disaster occurs some people accept that it wasnt our fault, others have to find someone to put the blame on and accuse as the culprit. 4 Connect the Dots Make the links between the subject you chose and the actors (those responsible for the conspiracy), revealing what has been industriously hidden by the conspirators until now. Some examples of the conspiracy theories are the Escape of Adolf Hitler and the planning of 11th September. Ana Rita Loureiro Examples of Conspiracy Theories There are documents that â€Å"prove† that Hitler didn’t committed suicide in 1945, after knowing that Nazis didn’t won the war. Moreover, it’s believed that he escaped in a submarine to Argentina. Two journalists, Simon Dunstan and Gerrard Williams, wrote Grey Wolf: The Escape Of Adolf Hitler that talks about the journey till his arrival, and the life he had in Argentina. Some people even believed that the famous skull that have the bullet hole of Hitler’s suicide is not his head, but â€Å"RochusMisch, Hitler’s former radio operator and the last survivor of the Berlin bunker, says he saw the bodies of ‘the boss’ and Eva Braun with his_own_eyes.†[2] About 11th September, many people refuse the official story. Many of them believe that the attack was generated by the US government, to provide political benefits to the country. Supposedly, the plan was explained to terrorists so that they could prepare the attack because, f or the society, is almost impossible to believe that 19 terrorists managed to cause all that chaos and destruction for themselves. In the Internet, there is a theory that says that if we write in the Word â€Å"Q33 NY† in the font â€Å"wingdings†, we obtainà ¯Ã¢â€š ¬Ã‚  Ãƒ ¯Ã‚ Ã¢â‚¬ËœÃƒ ¯Ã¢â€š ¬Ã‚ ³Ãƒ ¯Ã¢â€š ¬Ã‚ ³Ãƒ ¯Ã¢â€š ¬Ã‚  Ãƒ ¯Ã‚ Ã… ½Ãƒ ¯Ã‚ Ã¢â€ž ¢, which reminds us of the attack that caused the crash of the twin towers and the death of a lot of US citizens. People who are fan of the theories of conspiracy begin to make some associations. Catarina Pereira How the Government mutes the Social Media? Sometimes, a few journalists tend to investigate by their own something that they think it has to be investigated, even when their superiors stop that investigation. When they try to find out the truth about something that the government doesn’t want them to find, what does the Government do? Conspiracy theories begin when journalists try to find the truth and try to tell the people what they’ve discovered, but when the government doesn’t want that truth to come out, it’s quite easy to just mute the journalists that tried to speak to the society. A journalist is powerless compared to the government, so the government just speaks to the people and say â€Å"that’s not true†, even when the journalists have a lot of evidences. The government has a lot more influence on the society because we all know the power they have. Even if we consider believing that the conspiracy is true, the government can easily change our minds with the influence they have over the society, even over the social media. Some people can’t even consider to believe in what the media say because of the influence that the government as over them. In the other hand, people that believe in the conspiracy theories don’t listen to the government. Those people feel powerless about something and don’t trust the political power and, sometimes, people that have evidence on their own, who saw or had experienced something, made them believe that conspiracy theories are actually true. Ana Margarida Dinis Conclusion In one hand, we all know that Conspiracy theories are not easy to believe because it lacks of evidence and sustainable proves. But in the other hand, it’s a fact the people always tend to believe in theories and convictions that can comfort us, and sometimes, all the mystery involving some events, makes us a little bit more curious, wary and open minded to this speculations. As Dan Brown says in Da Vinci Code, â€Å"Everyone loves a conspiracy.† Television, but mostly Internet, are the greatest boosters to make people believe in conspiracy theories. We found an article about this subject in a famous Portuguese magazine, that says that â€Å"World Wide Web gives voice to a lot of crazy and scary conspiracy theories about everything people can imagine. To more depressing to the funnier, going through the absurd (†¦)†[3]. There are some sceptical people who despite this theories, and also people who consider them ridiculous. But we, as a bio, psico, socio and cultural beings, believe that even if we aren’t sure about something, we have to keep an open mind and we can’t reject it without knowing at least a little bit about the subject. Ana Rita Rebelo Webgraphy BRAIN, Marshall (n.d.). How Conspiracy Theories Work. How stuff Works?.  Available inhttp://people.howstuffworks.com/conspiracy-theory.htm [Consulted  in 19th May, 2014] DEWSBURY, Rick; HALL, Allan HARDING, Eleanor (18th October, 2011).  Did Hitler and Eva Braun flee Berlin and die (divorced) of old age in   Argentina?. Daily Mail. Available in http://www.dailymail.co.uk/news/article-2050137/Did-Hitler-Eva-Braun-flee-Berlin-die-old-age-Argentina.html  [Consulted in 19th May, 2014] ScienceDaily (28th November, 2012); Porque as pessoas acreditam em teorias  da conspiraà §Ãƒ £o?. Hypescience. Available in http://hypescience.com/porque-as-pessoas-acreditam-em-teorias-da-conspiracao/ [Consulted in 19th May,  2014] SILVA, Sandra (2010). Teorias da Conspiraà §Ãƒ £o: Seduà §Ãƒ £o e Resistà ªncia a partir   da Literacia Medià ¡tica. Tese de Mestrado, Faculdade de Letras da  Universidade do Porto. Available in http://repositorio-aberto.up.pt/bitstream /10216/55681/2/TESEMESSANDRASILVA000126278.pdf [Consulted in 19th  May, 2014] Teorias da conspiraà §Ãƒ £o que correm na Internet (29th April, 2014). Visà £o.  Available in http://visao.sapo.pt/teorias-da-conspiracao-que-correm-na-internet=f778634 [Consulted in 21th May, 2014] [1]Available in SILVA, Sandra (2010). Teorias da Conspiraà §Ãƒ £o: Seduà §Ãƒ £o e Resistà ªncia a partir da Literacia Medià ¡tica. Tese de Mestrado, Faculdade de Letras da Universidade do Porto. Available in http://repositorio- aberto.up.pt/bitstream /10216/55681/2/TESEMESSANDRASILVA000126278.pdf [Consulted in 19th May, 2014] [2]Available in DEWSBURY, Rick; HALL, Allan HARDING, Eleanor (18th October, 2011). Did Hitler and Eva Braun flee Berlin and die (divorced) of old age in Argentina?.Daily Mail. Available in http://www.dailymail.co.uk/news/article- 2050137/Did-Hitler-Eva-Braun-flee-Berlin-die-old-age-Argentina.html[Consulted in 19th May, 2014] [3]AddaptedfromTeorias da conspiraà §Ãƒ £o que correm na Internet (29th April, 2014). Visà £o. Available in http://visao.sapo.pt/teorias-da-conspiracao-que-correm-na-internet=f778634 [Consulted in 21th May, 2014]

Analysis and Design of Software Architecture Essay

Outline 1 2 3 4 5 6 7 8 Development Process Requirements Quality Attributes Runtime QA Non-runtime QA Requirements Analysis: Example Architectural Analysis & Design Architectural Views Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 2 / 78 Development Process Methodology Diï ¬â‚¬erent software development processes have software architecture as a part of the process Rational uniï ¬ ed process Spiral development method Agile development method Evolutionary rapid development Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 3 / 78 Development Process Place of SA in SDP Figure: Source: Software Architecture Primer by Reekie, McAdam Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 4 / 78 Development Process Methodology After the initial requirements analysis but before software design The ï ¬ rst architecture is also a communication basis with the customer Inputs for the development of the architecture: 1 2 Requirements Context (technical, organizational, business, †¦) Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 5 / 78 Requirements Analysis At the beginning there is always a customer who wants a speciï ¬ c software system Customer â€Å"wishes† are always informal Interviews, some documents, some Excel tables, †¦ We need to analyze such informal records and structure it Requirements engineering is a huge ï ¬ eld but we just illustrate here one possibility Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 6 / 78 Requirements Analysis The results of the requirements analysis: 1 2 Functional requirements Non-functional requirements (a) Runtime qualities (b) Non-runtime qualities 3 Contextual requirements Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 7 / 78 Requirements Functional requirements A technical expression of what a system will do Arise from stakeholder needs Structured language: software requirements speciï ¬ cation Use cases: structured description of user interactions with the system Formal models: e.g. state-charts Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 8 / 78 Requirements Non-functional requirements Other needs than directly functional or business-related Generally expressed in the form of quality-attributes Runtime quality attributes Non-runtime quality attributes Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 9 / 78 Requirements Contextual requirements What technology is available? Expertise of the development team Previous experience of users/customers Technical, business, market, legal, ethical, †¦ Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 10 / 78 Quality Attributes Need to address QAs Without any need for performance, scalability, †¦ any implementation of functionality is acceptable However, we always need to take into account the broader context E.g. hardware, technological, organizational, business, †¦ The functionality must be there but without proper addressing of QA it is worth nothing Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 11 / 78 Quality Attributes Inï ¬â€šuence on QAs Typically, a single component can not address a QA completely Any QA is inï ¬â€šuenced by multiple components and their interactions E.g. a UI component has a high degree of usability: however, usability of the system is compromised if a data management component has poor performance in accessing the data → users need to wait long → poor usability Components and their interactions → software architecture QAs are directly inï ¬â€šuenced by software architecture Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 12 / 78 Runtime QA PURS PURS (performance, usability, reliability, security) Performance: time performance, memory, disk, or network utilization Usability: human factors, easy to learn, easy to use, †¦ Reliability: availability, safety, †¦ Security: authentication, data protection, †¦ Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 13 / 78 Runtime QA Performance Time performance is most obvious Measured in the number of operations per second Also, latency: the time from receiving an input and producing an output Other measures: memory, disk, network utilization or throughput Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 14 / 78 Runtime QA Performance Diï ¬â‚¬erent measures are typically traded oï ¬â‚¬ against each other E.g. increasing throughput may increase latency Time performance might be increased with more memory True performance of the system is not only deï ¬ ned by performance of single components But also by their interactions and the overall processes in the system Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 15 / 78 Runtime QA Performance factors Choice of algorithms Database design Communication Resource management Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 16 / 78 Runtime QA Choice of algorithms Performance of algorithms is measured by their complexity (big O) E.g. linear complexity: O(n) Running time increases in direct proportion to the size of the data E.g. polynomial complexity: O(n2 ) It does not scale: double size of the data – running time increased by factor of 4 Goal: O(nlog (n)) Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 17 / 78 Runtime QA Database design Performance of database queries can dominate the overall performance The design of the tables has enormous impact on the overall performance Techniques to improve it: lazy evaluation, replication, caching Some additional cost to manage replication and/or caching In-memory databases (real-time systems) Developing a new database (search engines) Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 18 / 78 Runtime QA Communication Network overhead Package data according to a protocol, sending data over network Each layer means additional overhead Think how to use network: packaging binary data as XML!? Use more compact formats, e.g. JSON vs XML Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 19 / 78 Runtime QA Resources management Overloaded components need to be avoided A chain is only as strong as its weakest link! E.g. a single-threaded shared resource is in use: all other threads are blocked Very diï ¬Æ'cult to track down Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 20 / 78 Runtime QA Usability Usability is a very rich ï ¬ eld If usability is important you will need a usability expert Combination of many factors: responsiveness, graphical design, user expectations, conï ¬ dence Measuring with time taken to complete task, error rate, time to response, †¦ Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 21 / 78 Runtime QA Responsiveness and data availability An example of relations between QAs Usability requires that the system responds to user actions within a certain period of time If it is a complex system this need translates into performance along the path of the user action Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 22 / 78 Runtime QA Responsiveness and data availability Figure: Usability vs. Performance Source: Software Architecture Primer by Reekie, McAdam Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 23 / 78 Runtime QA Discussion on relations between QAs This diagram shows that we need to pay attention to tuning communication between B and Y Performance of the communication channel is a consequence of a usability requirement Do we need to support security of the communication channel? Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 24 / 78 Runtime QA Discussion on relations between QAs This diagram shows that we need to pay attention to tuning communication between B and Y Performance of the communication channel is a consequence of a usability requirement Do we need to support security of the communication channel? We support QAs always only as a response to user needs Never because it is needed anyway! Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 24 / 78 Runtime QA Discussion on relations between QAs If we support security even if it is not needed Very often QAs exercise opposing forces on the system Security requires a lot of checking: performance will suï ¬â‚¬er → usability will suï ¬â‚¬er A minimalistic approach: develop only what is required! Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 25 / 78 Runtime QA Reliability In traditional engineering disciplines reliability measures the failure rate of the system Failure rate speciï ¬ ed by mean time to failure MTTF A related measure: mean time between failures MTBF MTTR is mean time to repair A is availability Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 26 / 78 Runtime QA Reliability MTBF = MTTF + MTTR A= A= MTTF MTBF MTTF MTTF +MTTR E.g. expected availability of Web systems: Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 27 / 78 Runtime QA Reliability MTBF = MTTF + MTTR A= A= MTTF MTBF MTTF MTTF +MTTR E.g. expected availability of Web systems: 1 (always up-and-running) =⇒ MTTF → ∞ Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 27 / 78 Runtime QA Reliability Increasing reliability involves testing However, impossible to prove that a system is correct, i.e. without bugs Acceptability of errors depends on the  nature of a system Personal desktop use: bugs are typically tolerated Enterprise level: medium reliability level High-reliable systems: bugs can be fatal Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 28 / 78 Runtime QA Security Increasingly important aspect of systems is security Because systems are exposed to threats Especially networked systems As with other QAs security is a set of related responses to user needs Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 29 / 78 Runtime QA Authentication Requirement for identiï ¬ cation of users with a system Users present credentials so that the system can identify them Typically username and password Other forms: certiï ¬ cates, smart cards, biometric features Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 30 / 78 Runtime QA Authorization After authentication authorization which functions and what data is available for users This information is captured in an authorization model Access control lists (ACL) deï ¬ ne who can access and how a resource might be accessed E.g. read access, write access, delete access, †¦ Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 31 / 78 Runtime QA Authorization Drawbacks of ACLs It is resource based, e.g. a page in a CMS Often, authorization needs to address functions or tasks Also, managing of ACLs is diï ¬Æ'cult, e.g. subresources of resources Also, performance problems with checking Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 32 / 78 Runtime QA Authorization Another model: role-based access control (RBAC) Roles are used to manage many-to-many relations between users and permissions Roles are used to represent the job functions, e.g. author, teacher, student in an E-learning system Permissions are modeled as parts of roles, e.g. create page, create tests, †¦ Users are than assigned to a role and acquire automatically permissions of that role Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 33 / 78 Non-runtime QA MeTRiCS MeTRiCS (maintainability, evolvability, testability, reusability, integrability, conï ¬ gurability, scalability) Maintainability: how easy can you ï ¬ x bugs and add new features Evolvability: how easy your system copes with changes Testability: how easy can you test the system for correctness Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 34 / 78 Non-runtime QA MeTRiCS Reusability: how easy is to use software elements in other contexts, e.g. a software library Integrability: how easy you can make the separately developed components of the system work correctly together Conï ¬ gurability: how easy can a system be conï ¬ gured for diï ¬â‚¬erent installations and target groups Scalability: how easy the system copes with a higher performance demand Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 35 / 78 Non-runtime QA Maintainability This QA considers the whole lifecycle of a system What happens during system operation? Property that allows a system to be modiï ¬ ed after deployment wirh ease E.g. extensible, modiï ¬ ed behavior, ï ¬ xing errors Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 36 / 78 Non-runtime QA Maintainability At the design and implementation level Code comments Object-oriented principles and design rules Consistent programming styles Documentation Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 37 / 78 Non-runtime QA Maintainability Maintainability is very important because any software system will change over time Experience shows that such changes tend to degrade the system over time Software systems are subject to entropy The cumulative eï ¬â‚¬ect of changes degrades the quality of the system Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 38 / 78 Non-runtime QA Maintainability The systems tend to become messy systems Regardless of how a nice plan you had at beginning Design for change – recollect OO design rules Abstract messy parts of the system so that they can be exchanged Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 39 / 78 Non-runtime QA Maintainability Don’t be afraid to refactor and rewrite and redesign Each software vendor does this with major versions Create throw-away prototypes Think out-of-box and innovate Don’t always follow a hype – very often nothing new in hypes E.g. Web services Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 40 / 78 Non-runtime QA Testability Means to improve testability Test cases: if something fails there is a bug Separation of the testing framework and the system, i.e. testing with scripts from outside Logging Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 41 / 78 Non-runtime QA Conï ¬ gurability Ability of a system to vary its operational parameters without re-compiling or re-installing E.g. selecting appropriate database drivers, conï ¬ guring network parameters, †¦ Typically, realized by a set of conï ¬ guration ï ¬ les E.g. Apache Web server conï ¬ guration ï ¬ le sets host name, virtual hosts, †¦ Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 42 / 78 Non-runtime QA Conï ¬ gurability Conï ¬ gurability interacts with other QAs such as testability, maintainability, reliability High degree of conï ¬ gurability tends to have a negative impact on those QAs Testing of diï ¬â‚¬erent system conï ¬ guration becomes more diï ¬Æ'cult → reliability compromised Conï ¬ gurable components will be strongly parametrized → decreased maintainability Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 43 / 78 Non-runtime QA Scalability Ability of a system to increase its capacity without re-compiling or re-installing E.g. serving additional Web pages means only copying these Web pages into a Web server ï ¬ le system Sometimes increasing capacity means increasing hardware, e.g. Web server clusters Managing user session on the client side, means only providing additional code-on-demand from the server Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 44 / 78 Requirements Analysis: Example System description Web-based Network Analysis Tool: W-NAT A simple and usable system for network analysis is needed. Networks are entities that contain not only individuals but also their connections with other individuals (see e.g. 3 for an example). The system accepts a network representations as a list of pairs of connected nodes stored in a dataset ï ¬ le. Nodes are represented as integers. An edge between two nodes is stored as a line containing two nodes delimited by a tabulator. Users might upload datasets to the systems and store them for further analysis. Each user might upload multiple datasets and can execute various analysis on those datasets. The system keeps the track of the analysis history for each user. Users may calculate degree distributions, network diameter, clustering coeï ¬Æ'cient, connectivity measures, singular values, and diï ¬â‚¬erent centrality measures. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 45 / 78 Requirements Analysis: Example System description Web-based Network Analysis Tool: W-NAT Users can execute various calculations on multiple datasets in parallel. The system must not be blocked if a calculation is currently under way. Rather it should be possible to start a new calculation, or view previous calculations, etc. In case of longer calculations the system needs to notify the user by e-mail when the calculation is over. The results of the calculations should be available in textual and in graphical form. All results can be also downloaded to a local computer. The system will be used by a group of students that learn the basics of network analysis. It is expect that at any times the system will be used by multiple users executing multiple calculations. Since the system is primarily an educational tool it needs to be didactically sound, i.e. simplicity and usability are very important. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 46 / 78 Requirements Analysis: Example System description 6 How to search in a small world Pajek Figure 2: HP Labs’ email communication (light grey lines) mapped onto the organizational hierarchy of HP Labs constructed out the e-mail communication. Figure: Social network(black lines). Note that communication tends to â€Å"cling† to of formal organizational chart. From: How to search a social network, Adamic, 2005. with one another. The h-distance, used to navigate the network, is computed as follows: individuals have h-distance one to their manager and to everyone they share a manager with. Distances are then recursively assigned, so that each individual has h-distance 2 to their ï ¬ rst neighbor’s neighbors, and h-distance 3 to their second Denis Helic (KMI, TU neighbor’s neighbors, etc. SA Analysis and Design Graz) Oct 19, 2011 47 / 78 Requirements Analysis: Example System description Web-based Network Analysis Tool: W-NAT The system is a Web-based system and the users should be able to operate the system by using a standard Web browser. The users need not install any additional plugins to operate the system. User perceived performance of the system should be acceptable. In addition, standard Web usability concepts need to be followed. In particular, browser back button must be working at all times and it should be possible to bookmark pages at all times. Finally, standard Web design principles should be satisï ¬ ed, meaning that pages are valid (X)HTML pages in at least HTML Transitional. The system needs to support cross browser compatibility. Further, each page and each important application state needs to have a unique and human-readable URL. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 48 / 78 Requirements Analysis: Example Functional requirements UR1: The system is a network analysis tool. The system can calculate the following measures. UR1.1: UR1.2: UR1.3: UR1.4: UR1.5: Out-degree distribution In-degree distribution Cumulative out-degree distribution Cumulative in-degree distribution Hop plot Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 49 / 78 Requirements Analysis: Example Functional requirements UR1: The system is a network analysis tool. The system can calculate the following measures. UR1.6: Clustering coeï ¬Æ'cient UR1.7: Distribution of weakly connected components UR1.8: Distribution of strongly connected components UR1.9: Left singular vector UR1.10: Right singular vector Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 50 / 78 Requirements Analysis: Example Functional requirements UR1: The system is a network analysis tool. The system can calculate the following measures. UR1.12: UR1.12: UR1.13: UR1.14: UR1.15: Network singular values Degree centrality Closeness centrality Betweenness centrality Eigenvector centrality Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 51 / 78 Requirements Analysis: Example Functional requirements UR2: Networks are stored in dataset ï ¬ les. UR3: The dataset ï ¬ le has the following format. NodeID1 NodeID2 UR4: Users can upload multiple datasets to the system. UR5: To perform an analysis users select a dataset and then choose a measure to calculate. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 52 / 78 Requirements Analysis: Example Functional requirements UR6: For each user and for each dataset the system manages a history of calculations. UR7: Users may initiate multiple calculations simultaneously. UR8: When a calculation is started the system is not blocked. UR9: The system notiï ¬ es users about a ï ¬ nished calculation by e-mail. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 53 / 78 Requirements Analysis: Example Functional requirements UR6: For each user and for each dataset the system manages a history of calculations. UR7: Users may initiate multiple calculations simultaneously. UR8: When a calculation is started the system is not blocked. UR9: The system notiï ¬ es users about a ï ¬ nished calculation by e-mail. When is this notiï ¬ cation needed? If the user is logged out? Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 53 / 78 Requirements Analysis: Example Functional requirements UR10: The calculation results are presented in a textual as well as in a graphic form. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 54 / 78 Requirements Analysis: Example Functional requirements UR10: The calculation results are presented in a textual as well as in a graphic form. Which form? Format? Graphics format? Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 54 / 78 Requirements Analysis: Example Functional requirements UR10: The calculation results are presented in a textual as well as in a graphic form. Which form? Format? Graphics format? UR11: Users can download the calculation results. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 54 / 78 Requirements Analysis: Example Functional requirements UR10: The calculation results are presented in a textual as well as in a graphic form. Which form? Format? Graphics format? UR11: Users can download the calculation results. Single results? All results? Archived, how archived? Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 54 / 78 Requirements Analysis: Example Functional requirements UR10: The calculation results are presented in a textual as well as in a graphic form. Which form? Format? Graphics format? UR11: Users can download the calculation results. Single results? All results? Archived, how archived? UR12: Users can register with the system. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 54 / 78 Requirements Analysis: Example Functional requirements UR10: The calculation results are presented in a textual as well as in a graphic form. Which form? Format? Graphics format? UR11: Users can download the calculation results. Single results? All results? Archived, how archived? UR12: Users can register with the system. How register? E-mail? Captcha? Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 54 / 78 Requirements Analysis: Example Functional requirements UR10: The calculation results are presented in a textual as well as in a graphic form. Which form? Format? Graphics format? UR11: Users can download the calculation results. Single results? All results? Archived, how archived? UR12: Users can register with the system. How register? E-mail? Captcha? UR13: Users can login and log out. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 54 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Performance Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Performance How many users? Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Performance How many users? UR3: Authentication should be supported. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Performance How many users? UR3: Authentication should be supported. Security Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Performance How many users? UR3: Authentication should be supported. Security UR4: User-perceived performance must be acceptable Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Performance How many users? UR3: Authentication should be supported. Security UR4: User-perceived performance must be acceptable Performance and Usability Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Performance How many users? UR3: Authentication should be supported. Security UR4: User-perceived performance must be acceptable Performance and Usability How many seconds at max users can wait? Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Performance How many users? UR3: Authentication should be supported. Security UR4: User-perceived performance must be acceptable Performance and Usability How many seconds at max users can wait? UR5: Web-based system should be available at all times. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR1: The system is simple, usable and didactically sound. Usability UR2: The system needs to support multiple users simultaneously. Performance How many users? UR3: Authentication should be supported. Security UR4: User-perceived performance must be acceptable Performance and Usability How many seconds at max users can wait? UR5: Web-based system should be available at all times. Reliability Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 55 / 78 Requirements Analysis: Example Non-functional requirements UR6: Human-readable URLs. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 56 / 78 Requirements Analysis: Example Non-functional requirements UR6: Human-readable URLs. Evolvability, reusability, maintainability, testability, integrability Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 56 / 78 Requirements Analysis: Example Non-functional requirements UR6: Human-readable URLs. Evolvability, reusability, maintainability, testability, integrability UR7: Extending the system with new metrics. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 56 / 78 Requirements Analysis: Example Non-functional requirements UR6: Human-readable URLs. Evolvability, reusability, maintainability, testability, integrability UR7: Extending the system with new metrics. Evolvability, reusability, maintainability, testability, integrability, conï ¬ gurability Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 56 / 78 Requirements Analysis: Example Non-functional requirements UR6: Human-readable URLs. Evolvability, reusability, maintainability, testability, integrability UR7: Extending the system with new metrics. Evolvability, reusability, maintainability, testability, integrability, conï ¬ gurability UR8: Reliability of a Web-based system. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 56 / 78 Requirements Analysis: Example Non-functional requirements UR6: Human-readable URLs. Evolvability, reusability, maintainability, testability, integrability UR7: Extending the system with new metrics. Evolvability, reusability, maintainability, testability, integrability, conï ¬ gurability UR8: Reliability of a Web-based system. Testability Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 56 / 78 Requirements Analysis: Example Non-functional requirements UR6: Human-readable URLs. Evolvability, reusability, maintainability, testability, integrability UR7: Extending the system with new metrics. Evolvability, reusability, maintainability, testability, integrability, conï ¬ gurability UR8: Reliability of a Web-based system. Testability UR9: Multiple users. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 56 / 78 Requirements Analysis: Example Non-functional requirements UR6: Human-readable URLs. Evolvability, reusability, maintainability, testability, integrability UR7: Extending the system with new metrics. Evolvability, reusability, maintainability, testability, integrability, conï ¬ gurability UR8: Reliability of a Web-based system. Testability UR9: Multiple users. Scalability Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 56 / 78 Requirements Analysis: Example Contextual requirements UR1: Web browser. UR2: Valid (X)HTML, at least (X)HTML Transitional. UR3: No browser plugins are allowed. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 57 / 78 Architectural Analysis & Design Analysis We analyze the requirements and try to identify so-called key concepts Understanding of the domain Static part of the domain We also try to identify key process and activities Dynamic part of the domain Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 58 / 78 Architectural Analysis & Design Design Design is the process of creating models (recollect the deï ¬ nition of SA) Two basic types of architectural models Structure and behavior Architectural structure is a static model of a system (i.e. how the system is divided into components) Architectural behavior is a dynamic model of a system (i.e. how the components interact with each other to perform some useful work) Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 59 / 78 Architectural Analysis & Design Architectural structure The division of a system into components and connectors To represent the model: box-and-lines diagrams (to see at a glance important concepts) It is important to remember that diagrams are only representations of the model Diagrams must always be accompanied by additional material such as text, data models, mathematical models, etc. The combination of diagrams and additional material is an architectural model Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 60 / 78 Architectural Analysis & Design Architectural structure What is a component? What is a connector? Components might be subsystems, separate processes, source code packages, †¦ Connectors might be network protocols, method invocations, associations, †¦ The combination of diagrams and additional material is an architectural model Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 61 / 78 Architectural Analysis & Design Architectural structure Figure: Example of an architectural structure Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 62 / 78 Architectural Analysis & Design Architectural structure In the diagram we have one user-interface and one database component But what is the criteria for deciding what is a component? Separate program modules? Separate threads or processes? Conceptual or functional division? And what about connectors? Network protocols? Callbacks? Request/response cycles? Method invocations? Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 63 / 78 Architectural Analysis & Design Architectural structure What is the level of granularity of a diagram? E.g. for a Web-based system, components are servers and browsers and connector is HTTP But, components of a server are HTTP parser, ï ¬ le I/O, cache, plug-ins, †¦ Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 64 / 78 Architectural Analysis & Design Architectural structure Comparison with OO: a component is an object and a connector is a message sent between two objects Because models in OO are very well deï ¬ ned Therefore, we need additional information that accompanies diagrams To describe criteria for decomposition and provide explanations on granularity Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 65 / 78 Architectural Analysis & Design Architectural behavior Complementing structure is architectural behavior Interaction of system elements to perform some useful work Functionality vs. behavior Functionality is what the system can do and behavior is the activity sequence Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 66 / 78 Architectural Analysis & Design Architectural behavior Example: Accessing a tweets document Request is sent to the Web presentation layer That layer forwards the request to the application logic, e.g. TweetDeck TweetDeck contacts TweetViews to obtain a particular template, then retrieves the data from TweetDB wraps it into an HTML response and sends the response to TweetUI Functionality allows me to display a tweets document, behavior is the sequence of activities that makes it happen Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 67 / 78 Architectural Analysis & Design Architectural behavior Each component has a set of responsibilities Behavior is the way how these responsibilities are exercised to respond to some event An event may be an action of the user or an event from an external system A particular behavior is an event plus a response in the form of a sequence of component responsibilities Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 68 / 78 Architectural Analysis & Design Architectural behavior To represent behavioral models we use use-case map notation by Buhr A use-case map consists of a trace drawn through a structural diagram of the system The path of the trace through a structural diagram shows the sequence of activities Each crossing of a component by the trace indicates exercising of a responsibility Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 69 / 78 Architectural Analysis & Design Architectural behavior Figure: Types of traces in use-case maps Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 70 / 78 Architectural Analysis & Design Architectural behavior (a) Single trace – all responsibilities exercised sequentially (b) Two traces are consecutive: Equivalent to single trace but shows that continuation is triggered by another event (c) And-Fork: The traces after the line are potentially concurrent (run in parallel) Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 71 / 78 Architectural Analysis & Design Architectural behavior Figure: Types of traces in use-case maps Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 72 / 78 Architectural Analysis & Design Architectural behavior (a) N-Way And-Fork: the trace after the fork may be replicated an arbitrary number of times (b) Or-Fork: The trace is split and activity proceeds along one or another path (c) Seq-Fork: The traces after the line are followed in the order indicated by the arrow Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 73 / 78 Architectural Analysis & Design Architectural behavior Figure: Example of architectural behavior Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 74 / 78 Architectural Views Architectural views We can examine a system from diï ¬â‚¬erent points of view Diï ¬â‚¬erent kinds of views Conceptual: components are set of responsibilities and connectors are ï ¬â€šow of information Execution: components are execution units (processes) and connectors are messages between processes Implementation: components are libraries, source code, ï ¬ les, etc and connectors are protocols, api calls, etc. Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 75 / 78 Architectural Views Architectural views There are other models as well We will mention them but we will investigate only previous three models Data model describes the data Physical model describes servers, ï ¬ rewalls, workstations, †¦ Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 76 / 78 Architectural Views Architectural views Each view provides diï ¬â‚¬erent information about the structure of the system Each view addresses a speciï ¬ c set of concerns All views taken together is the primary means of documenting software architecture Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 77 / 78 Architectural Views Architectural views The conceptual architecture considers the structure of the system in terms of its domain-level functionality The execution architecture considers the system in terms of its runtime structure The implementation architecture considers the system in terms of its build-time structure Denis Helic (KMI, TU Graz) SA Analysis and Design Oct 19, 2011 78 / 78

The Computer Of Computer Technology - 901 Words

Since the 1980 s, the growth of the technology sector has been exponential. The introduction of the personal computer (PC) was the true catalyst for the growth in popularity of computer technology. With this introduction also came the growth in popularity of being a computer scientist. The code used to write the software for these personal computers was brand new and easy to use. What made it easy to use was the fact that the computer code for the PC was very similar to the English language; whereas, previous computers used punch cards as a way to program them.. This change was revolutionary because it allowed anyone to learn how to program a computer. This, coupled with the major computer advancements occurring in the United States, such as the internet, created the idea that becoming a computer scientist almost guaranteed you a job. At the time, this was true. The idea still is mostly true, however, many computer science jobs, usually Information Technology (IT) and other entry lev el jobs that involve programming, have been moved overseas. This shift to outsourcing is not very widespread as some people might think, but it could become widespread with the increase in quality of life and job availability in other countries. The outsourcing, while currently not a major issue, does have very real consequences for the future. Such consequences include lack of job availability for college graduates in the United States and, as a result, an increase in unemployment. AnotherShow MoreRelatedComputer Advancement Of Computer Technology1139 Words   |  5 PagesThe only question is that how much farther can we go in the advancement of computer technology to support people. One of the ways to support people is in the area of Firefighting. In this field the firemen with help of computers is allowed to help civilians when they are in need. The job of now is becoming a little safer to do because of newly advances by computers in the firefighting field. Three important ways computers have contributed is in the ways firemen can refine their own personal knowledgeRead MoreComputer Technology And Pharmacy : Computers1713 Words   |  7 PagesOctober 27, 2015 Computer Technology and Pharmacy Computer Technology and Pharmacy Over the past 40 years, information technology has had a major impact on the working lives of millions of people. Many industries have embraced computer technology because of the benefits of automated information processing. More importantly, Computers is a major part of our every day activities and it would be devastating if it was taking away because everything we do in some way requires a use of a computer. Some of theRead MoreComputer Technology1733 Words   |  7 PagesComputer technology is advancing at a rapid rate, causing the diversity and availability of assistive technology computer resources to have a tremendous impact for special education students across the United States. Assistive technology provides an opportunity for students with physical, emotional, and mental disabilities to acquire universal access to tools and opportunities for learning. Despite studies showing the benefits of assistive technology, many school districts fail to achieve the fullestRead MoreCo mputer Technology And Its Impact On Computer Crime1296 Words   |  6 Pagesuse of computer technology to disrupt the activities of a state or organization, especially the deliberate attacking of information systems for strategic or military purposes† (Oxford Dictionary, 2016). While this definition may seem fitting on a global basis the idea of cybercrime can encompass any valuable information of an individual, company, government, or military entity. The term hacker came about in the early 80’s defining a coup of people where were proficient at manipulating computers. HoweverRead MoreComputer And Internet Technology : Computer Hardware1532 Words   |  7 Pages Computer and Internet Technology Computer Hardware A report for Geoff Wingfield By Joseph Key 9th December 2014 Contents 1.0 Introduction 3 2.0 Why Copper Tracks (Busses) Are Ultimately Limited In How Much Data Can Be Delivered By Them Per Second 3 2.1 Why Devices Such As Microprocessors Get Hot And Why The Heat Increases With Higher Clock Rates 3 2.2 Cost Of A PC Running 3 3.0 Describe How The Latest Technology Is Used To Optimise Its Operation For Speed 4 4.0 Cost Of Building ARead MoreEssay On Computer Technology1000 Words   |  4 PagesComputer technology is one of the key drivers in the twenty first century. The technology has led to new business models and new types of businesses. Higher education institutes are now spending million to implement computer technology projects like institute management, campus management, student management etc. computer technologies could save higher education institutes millions of dollars. Computer technology is the design and construction of computers to better help people at work, school, homeRead MoreComputer Security And The Technology1273 Words   |  6 PagesIntroduction: As time has gone on, society has advanced and the age of the computer came about, bringing its own advantages and concerns. One such concern was the question of computer security and personal information staying safe. It seems there has always been some form of computer security, however this form is dynamic, always changing and advancing. This is due to the fact that the technology that is made to bypass security is changing and advancing just as rapidly. Such as the progressionRead MoreEvolution of Computer Technology1581 Words   |  7 Pagesof inventions made by different people into modern forms. Single inventors rarely bring out modern invention. What we have now as electronic devices (the computers) are inventions of several scientists, mathematicians and engineers from different centuries. For the purpose of this mini research key terms like evolution, technology and computer shall be considered, not forgetting to take a careful look at the evolution of these invention s from different centuries/years to our present generation startingRead MoreTechnology And The Computer System760 Words   |  4 Pagesin the computer system after information are deleted. For instance, after an address is programmed on the GPS to retrieve and lead to a destination, the information is automatically encoded and released to track the direction leading to the desired address. Just like the human brain, the computer has the capacity to capture and memorize multiple information, and may proceed by a rapid retention after some information are deleted. It seems like when an information is erased from the computer, it attemptsRead MoreThe Technology Behind A Computer1256 Words   |  6 PagesSTATEMENT OF PURPOSE When I realized that the technology behind a computer’s operation could be used to solve a myriad of problems my interest in the field went far beyond browsing the net or playing computer games. My interest was further piqued by my elder sister who explained the intricacies involved in the projects she worked on during her Masters in Computer Application. After that, assured of her guidance, I opted for C++ as an elective in high school, and went on to enjoy the experience of