Tuesday, August 25, 2020

On the Idle Hill, The Drum and Drummer Hodge Essay

Artists regularly compose sonnets to communicate their thoughts, conclusions, feelings and encounters of life. Pick three sonnets you have concentrated to show how scholars have been impacted by the occasions of war. War, in any shape or structure, influences individuals from numerous points of view. Numerous individuals decide to communicate their emotions and encounters of war in sonnets. The three sonnets I have picked all have various states of mind, structures and rhythms yet their implications are no different †war is merciless alarming and silly. The sonnet ‘On the Idle Hill’ is by A.E. Housman. Housman composed the sonnet in 1896 and he was not expounding on a specific war however simply the ghastliness of fight when all is said in done. Housman never participated in any war yet caught wind of the dread of it from different people’s encounters. The main refrain depicts a quiet, cheerful, warm scene. Words, for example, ‘summer’, ‘sleepy’ and ‘streams’ underscore this. Be that as it may, the ‘steady drummer’ slices through this quiet environment. It is the sound of the military coming, searching for newcomers to do battle with them. The main verse is by all accounts about the drum and how it calls individuals to war and tears them away from their homes. The line; ‘Drumming like a commotion in dreams.’ causes the drum to appear to be a bad dream, something everybody fears. In the subsequent verse, the tone is significantly more troubled and darker. The expressions, ‘Far and near’ and ‘low and louder’ are proposing that war is all over the place, and can be seen in various levels everywhere throughout the world. Presumably one of the most striking and ground-breaking lines in the sonnet, ‘Dear to companions and nourishment for powder’ is stunning and adds an increasingly close to home topic to the sonnet, in light of the fact that the warriors are currently being viewed as companions, fathers and genuine individuals rather than just toys in war. The ‘powder’ is explosive so the writer is alluding to the way that the men are only nourishment for the war. The war is made to seem like a genuine living thing; this is a genuine case of exemplification. The last line of verse two, ‘Soldiers walking, all to die.’ is discouraging and it accentuates the pointlessness and loathsomeness of war. Verse three keeps up the dismal, discouraging tone. There is all the more remarkable and realistic symbolism, for example, ‘bleach the bones’, which is extremely vile and stunning, and, ‘of friends slain’. ‘Slain’ doesn't simply mean slaughtered, it implies killed and it diagrams the mercilessness of war. Another realistic expression is, ‘Lovely chaps and dead and rotten’. These are differentiating pictures, and the author is attempting to put the thought over that blameless, great individuals can be slaughtered in war for reasons unknown. The last line of the verse, ‘None that go return again.’ summarizes A.E. Housman’s see on war †that it is simply something which ends the lives of any individual who battles in it and has no point at all. The rhyme in ‘On the Idle Hill’ is ‘abab’ and it keeps a moderate, consistent beat all through the sonnet, giving a miserable, despairing tone to the sonnet. The structure wherein the author has set out the sonnet, in four verses, is successful in light of the fact that every one discussions about an alternate part of war. This sonnet shows A.E. Housman’s disdain of fight and how silly and merciless he thinks it is. War has clearly affected him profoundly and we can see from his language all through the sonnet that he feels firmly about it. The sonnet ‘The Drum’ was composed by John Scott, who was a Quaker. The noteworthiness of this is as per Quaker convictions, he was a conservative as was totally against war and savagery. His sonnet focuses on the popular enrollment drum which called individuals to was. He opens the sonnet straightforwardly by saying, ‘I abhor that drum’s conflicting sound,’. We quickly recognize what Scott’s emotions about war are †he abhors it. Indeed, even the cadence is drum-like, as found in the redundancy of the word ’round’. This has a sleep inducing impact, much the same as the drum was to knew initiates. Scott is angry about the drum and scrutinizes its capacity to spellbind youngsters, as found in the expression, ‘To negligent youth it delight yields.’ The artist is stating that the drum nearly exploits the youngsters. The following two lines, ‘To sell their freedom for charms Of cheap ribbon, and sparkling arms.’ are recommending that was takes your opportunity for something material and useless, the uniform and the weapons. The poet’s considerations here are that was may appear to be energizing and an opportunity to be a saint yet it is truly taking your opportunity and life. Scott utilizes the words ‘tawdry’, ‘charms’, and ‘glittering’ to make a picture of respect and magnificence. In the accompanying line, Scott makes the word ‘Ambition’ appear to be an individual †this is a genuine case of exemplification. He is focusing on the way that ‘Ambition’, or the war officials, just need to provide one request to send you to your demise. The last line of verse one, ‘To walk, and battle, and fall in remote lands.’ is utilized by the artist to reveal to us that in war, you are continually coordinating to bite the dust. Refrain two starts with indistinguishable two lines from verse one, with the entrancing reiteration of the word ’round’. The artist currently places his own sentiments into the sonnet by saying ‘To me it speaks’. He utilizes ground-breaking symbolism, as found in the words ‘ravaged’, ‘burning’ and ‘ruined’, to make a scene of decimation and demise. Additionally, words, for example, ‘mangled’ and ‘dying’ incite frightfulness and dread in the reader’s mind. The accompanying line, ‘And widow’s tears and orphan’s moans.’ is discouraging and it shows the consequence of war †the families destroyed. The last two lines, ‘And all that Misery’s hand gives, To fill the index of human woes.’ are summarizing Scott’s see on war, it is horrendous, ruinous, trivial and unnerving. Once more, he utilizes embodiment and makes ‘Misery’ appear to be an individual. The structure where ‘The Drum’ is set out is very powerful †the primary verse is about the enlistment of men and the pointlessness of war and the second is about the result and the demise. The rhyming plan ‘abab’ is utilized all through the sonnet and it is drum-like in sound, which is fitting to the subject of the sonnet. In synopsis, ‘The Drum’ shows John Scott’s disdain of war. Being a radical, he clearly didn't battle in any wars however he thought enough about them to know about the devastation and passing which accompanied them. He has composed the sonnet to communicate his perspectives on war and furthermore to attempt to deter individuals from going to them. ‘Drummer Hodge’ was composed by Thomas Hardy after he read about a nearby drummer kid who had been slaughtered at war. He thought how tragic it was that a little fellow, who didn’t know the ghastliness of war, ought to be covered in an outsider scene so distant from home. The kid passed on in the Boer War (1899-1902), which occurred in South Africa. The sonnet has an exceptionally negative, tragic tone. The principal refrain is about how the little youngster is covered. The expressions ‘they throw’ and ‘uncoffined’ propose to us that no idea was placed into his internment and he had no legitimate memorial service. He wasn’t even given the advantage of a wooden box, he was simply tossed into a gap. Strong accentuates the way that he is miles from home with the expression ‘foreign constellations.’ The peruser feels frustrated about the poor kid, covered away from everything recognizable to him.

Saturday, August 22, 2020

Free Essays on Controversial Television Adversting

Questionable Television Advertising TV notices advancing flawless self-perceptions support the steady battle of ladies to accomplish the ideal body. Has our country been bamboozled by the media? Commercials have an enormous influence in our way of life; in any case, the pictures that are utilized in many notices are more dream than the real world. They depict excellent, flimsy individuals making some great memories with whatever item they are attempting to sell. The media realize that TV and radio projects are essentially fillers for the space between plugs (Kilbourne, 1999). They realize that the projects that succeed are the ones that convey the most noteworthy number of individuals to the publicists. From outset on, we get a tempting and unremitting message from promotions †items are supernatural and can satisfy our fantasies (Kilbourne, 1999). Promoting is intended to sell items. All the while, promotions likewise sell desires and impart ideas of worthy conduct and sexual orientation jobs. With the steady redundancy and availability it is an incredible medium. When little youngsters arrive at pre-adulthood, they have deserted children’s programming for increasingly grown-up arranged material. In spite of the fact that their media assets extend past TV to incorporate films, music, and adolescent magazines, TV publicizing is the most conspicuous in their day by day lives. With this comes expanded presentation to media messages, including those sent through publicizing. At an age where little youngsters start to reclassify themselves, the media frequently sends them messages that could confine their desires, subvert their self-esteem and imperil their wellbeing. It is l ikewise imperative to consider the monstrous number of ads indicated day by day. On the off chance that you stare at the TV for one hour daily, you will undoubtedly observe a similar business during each business break, or right around 6 times each hour. For individuals who stare at the TV for over one hour of the day, that number goes up. In the normal American home,... Free Essays on Controversial Television Adversting Free Essays on Controversial Television Adversting Dubious Television Advertising TV ads advancing flawless self-perceptions empower the steady battle of ladies to accomplish the ideal body. Has our country been misled by the media? Promotions have a huge influence in our way of life; notwithstanding, the pictures that are utilized in many notices are more dream than the real world. They depict lovely, slight individuals making some great memories with whatever item they are attempting to sell. The media realize that TV and radio projects are just fillers for the space between advertisements (Kilbourne, 1999). They realize that the projects that succeed are the ones that convey the most noteworthy number of individuals to the sponsors. From early stages on, we get an alluring and ceaseless message from advertisements †items are supernatural and can satisfy our fantasies (Kilbourne, 1999). Publicizing is intended to sell items. All the while, notices likewise sell desires and convey ideas of adequate conduct and sexual orientation jobs. With the consistent redundancy and availability it is an amazing medium. When little youngsters arrive at youthfulness, they have deserted children’s programming for increasingly grown-up arranged material. In spite of the fact that their media assets grow past TV to incorporate motion pictures, music, and high schooler magazines, TV publicizing is the most noticeable in their every day lives. With this comes expanded introduction to media messages, including those sent through publicizing. At an age where little youngsters start to reclassify themselves, the media frequently sends them messages that could constrain their yearnings, sabotage their self-esteem and imperil their wellbeing. It is likewise imperative to consider the gigantic number of notices indicated day by day. On the off chance that you stare at the TV for one hour daily, you will undoubtedly observe a similar business during each business break, or very nearly 6 times each hour. For individuals who sit in front of the TV for over one hour out of each day, that number goes up. In the normal American home,...

Friday, July 31, 2020

What Does It Mean to Be an American

What Does It Mean to Be an American Many essays, articles, and novels have been written on what it means to be an American. For someone, being a true American means living out the ideals of liberty and freedom. For others, Americans should embody the values of democracy and equality that are highlighted in our Constitution. Some may perceive Americans from a negative perspective, associating them with such concepts as consumerism, political hegemony, and arrogance. As with any other nation, none of these perspectives fully reflects the whole diversity of America and each individual specifically. I would like to describe what it means to be an American from my point of view. To begin with, being an American means living in an extremely diverse society. This diversity is manifested in personal, socioeconomic, cultural, ethnic, gender, and sexual differences that make this country so unique. Being an American means not only belonging to this bright picture of nations and worldviews but also respecting and celebrating the difference. I believe that a true American knows the history of the country and remembers that this nation has been formed by people from different countries and continents. Sustaining and supporting this diversity today is especially important given the current threats to the American society and lifestyle. Politicians divide the country by making people feel insecure and distrustful, while terrorists make us feel scared of any diversity, of young and talented people who are not allowed to come to the USA simply because they were born in the “wrong” place. So, for me, being an American is respecting and promoting diversity in all its manifestations. Furthermore, being an American means working hard every day. Our nation is famous for being hard-working and motivated, which is due to the exceptional commitment and drive of its people. Americans have achieved so much in science, education, culture, and business only because they are not afraid of hard work. On the contrary, they love working and pride themselves on being loyal and ambitious employees able to promote positive changes in their organizations. For me, being an American means enjoying work, no matter how hard it may be. However, no true work-related achievements are possible without a dream. Americans have always had ambitious goals, and they even have a unique concept of the American dream that attracts people from all over the world. I am convinced that Americans can dream globally, that is, aim to achieve or create something that would affect the whole humanity, not just the USA. Naturally, not all dreams can come true, and not everyone can achieve success, like in any other country. However, a true American believes that everything is possible with due diligence and a bit of luck. Finally, I think that being an American means being willing to make this world a better place. I do not agree with those arguing that Americans are selfish and think only about their own well-being and economic stability. I am convinced that the majority of people are empathetic and kind, and they would be glad to make a contribution to the global peace and stability. Some of them already do it by working on innovative medication, making amazing scientific discoveries, donating to international NGOs protecting the environment, and supporting developing countries. Our scientists have made an immense contribution to the global science and made the lives of millions of people better, which proves that being an American means thinking about other people. To summarize, I feel that being an American means much for every conscious citizen including me, as a true American respects diversity and hard work and has a dream that may make people’s lives better. This essay answers the question “What Does It Mean to Be an American?” The author argues that Americans possess many positive qualities, such as respect for diversity, diligence, ambition, and empathy, which allows them to make a valuable contribution to the global peace and stability.

Friday, May 22, 2020

The Nature of Death in Emily Dickinsons Poems Essay

Emily Dickinson once said, â€Å"Dying is a wild night and a new road.† Some people welcome death with open arms while others cower in fear when confronted in the arms of death. Through the use of ambiguity, metaphors, personification and paradoxes Emily Dickinson still gives readers a sense of vagueness on how she feels about dying. Emily Dickinson inventively expresses the nature of death in the poems, â€Å"I felt a Funeral, in my Brain (280)†, â€Å"I Heard a fly Buzz—When I Died—(465)â€Å" and â€Å"Because I could not stop for Death—(712)†. Emily Dickinson, who achieved more fame after her death, is said to be one of the greatest American poets of all time. Dickinson communicated through letters and notes and according to Amy Paulson Herstek, author of†¦show more content†¦Dickinson’s poems provide that secret gateway to the supernatural that Ferlazzo is referring to. In the poem â€Å"I felt a Funeral, in my Brain,† Emily Dickinson uses symbolism to convey some sort of mental funeral that the speaker is experiencing. The funeral image that Dickinson depicts in the first line of the poem: â€Å"I felt a Funeral, in my Brain,† does not literally represent a funeral, but it is used to symbolism a mental breakdown and agony that the speaker is going through. By using this symbolism, the speaker is imagining the death of old ways of thought. Dickinson writes that when the funeral service was â€Å"like a Drum—â€Å" (Dickinson 43) and that it â€Å"Kept beating—beating—till I thought My Mind was going numb—â€Å" (43), leaving readers believing that the speaker is going mad. By depicting this image, Dickinson reveals that with the death of old thought; there is some sort of numbness or pain that is necessary to â€Å"progress to a better state† (Goldfarb 2). By repeating the beating sound two times , along with the rhyming sequence in the previous lines of the poem, Dickinson is stressing the numbness and the importance of it. Dickinson uses ambiguity to stress the difficulty of knowing and understanding certain experiences and thoughts to the reader. By being deliberately elusive, Dickinson makes the speaker out to be some sort of hero. In a critical essay of â€Å"I felt a Funeral, in my Brain,† Sheldon GoldfarbShow MoreRelatedEmily Dickinson: An American Poet1793 Words   |  7 PagesEmily Dickinson is one of the most influential American authors, whose works transformed the way people view poetry and female authors. Her exceedingly complex life has proved a tremendous influence on her instrumental poetry, creating its originality and distinguishing her from other great poets of the nineteenth century. As well, her use of symbolism and imagery has continued to make her work celebrated. Although Emily Dickinson lived a private and reclusive life, full of death among many closeRead MoreSolitude Of A Poet By Emily Dickinson1545 Words   |  7 Pagesmost recognized and widely studied poet today. Bo rn in December 10, 1886 in Amherst, Massachusetts, Emily Dickinson was one of three children to Edward Dickinson and his wife, Emily Dickinson. According to Pettinger, Dickinson’s roots trace back to her Puritan ancestors from England in the 17th century, who later immigrated to America to freely exercise their religion (Pettinger, The Biography of Emily Dickinson). Dickinson was a quiet, intelligent individual, excelling in Amherst Academy, a schoolRead MoreEmily Dickinson Research Paper984 Words   |  4 PagesMichael Salvucci Mrs. Comeau English 10 Honors Death, Pain, and the Pursuit of Peace Although Emily Dickinson’s poetry is profoundly insightful, her poems have a very confinedpan of subjects and themes. Most likely due to her early life and social reclusion, Dickinson’s poetry is limited to three major subjects: death, pain, and on a somewhat lighter note, nature. Dickinson’s poetry is greatly influenced by her early life as she led an extre mely secluded and pessimisticlife. In her early adultRead MoreEmily Dickinson s Emily And The English Specking World Essay1744 Words   |  7 Pages Emily Dickinson Emily Dickinson is a very well-known poet. Emily wrote many poems. She has written 1700-2000 poems (4) According to Nicolas Tredell, there was â€Å"only eleven poems published during her lifetime.† (4) She did not know about most of them being published. Dickinson’s sister found the poems and turned them in to be published. Emily did not want her poems to be seen. Dickinson is one of the great poets. Her poems were produced by America and the English-specking world (1). Emily had aRead MoreEssay about Emily dickinson1145 Words   |  5 Pages Emily Dickinson’s poetry powerfully indicates values of society of the time. It does this through its conciseness, its simplicity and its control. Indications of society’s values are seen in many of Dickinsons poems, but they are especially noticeable in ‘It was not Death’, and ‘Because I could not stop for Death’. In Dickinson’s poem ‘It was not Death’, she demonstrat es how restricting and stereotyping society can be on an individual, and how society values the conformity of the whole communityRead MoreTheology Leads to Interpretation1336 Words   |  6 PagesEmily Dickinson’s extensive collection of poems on the subject of death can be better understood individually once time has been taken to view her works as whole. By viewing the works as a whole, it is possible to conclude a likely theological view point of the author and then apply this theology to the individual works in order to improve interpretation. Emily Dickinson’s poem â€Å"Because I could not stop for Death† is one such poem that when viewed individually is open to a wide scope of readingsRead MoreMortailty and Eternity in Emily Dickinson Poems Essay1541 Words   |  7 PagesEmily Dickinson is the epitome of the modern poet. Her poetry breaks from the traditional style with dashes to separate ideas. Dickinson, also, challenged the religious belief of her ti me. Growing up as a Puritan in Massachusetts, Emily Dickinson knew the bible, yet as an adult, she questioned that belief. Many of her poems seem focused on death; death of the body, death of the soul, death of the mind. Why was she so intrigued with death? The poems that embody this theme are: â€Å"Success is countedRead More A Comparison of the Poetry of Emily Dickinson and Robert Frost1062 Words   |  5 PagesThe Poetry of Emily Dickinson and Robert Frost The poetry of Emily Dickinson and Robert Frost contains similar themes and ideas. Both poets attempt to romanticize nature and both speak of death and loneliness. Although they were more than fifty years apart, these two seem to be kindred spirits, poetically speaking. Both focus on the power of nature, death, and loneliness. The main way in which these two differ is in their differing use of tone. The power of nature is a recurring themeRead MoreThe Works of Emily Dickinson726 Words   |  3 Pages Emily Dickinson’s writing reflects the Realistic period through personal themes: death, isolation, God, marriage, women in society, and love. Dickinson’s writing is affected by numerous factors. Among these are her family, the Realism period, and her life experiences. Emily Dickinson herself was a sort of mystery. Emily Dickinson’s background had a profound effect on her writing. Family always plays an important role in the upbringing of an individual. Her grandfather had a prominent position inRead More Emily Dickinson - Her Life and Poetry Essay627 Words   |  3 PagesEmily Dickinson - Her Life and Poetry Emily Elizabeth Dickinson was born December 10, 1830, into an influential family in Amherst, Massachusetts. Her father helped found Amherst College, where Emily later attended between 1840 and 1846. She never married and died in the house where she was born on May 15, 1886. Emily Dickinson’s reclusive life was arguably a result of her proposed bi-polar disorder. This life and disorder unduly influenced the themes of her poetry. She chose not

Sunday, May 10, 2020

Chronic Disease Rheumatoid Arthritis - 1333 Words

This paper will be addressing a chronic disease known as rheumatoid arthritis that â€Å"is an autoimmune disease in which the body’s immune system – which normally protects its health by attacking foreign substances like bacteria and viruses – mistakenly attacks the joints. This creates inflammation that causes the tissue that lines the inside of joints (the synovium) to thicken, resulting in swelling and pain in and around the joints.† (Foundation 2016) The interviewee in this paper, Robert Doe, age 68, has been diagnosed with this chronic autoimmune disease. This interview consisted of six questions in the home of Mr. Doe around his disease and the medications/substances used and what their long term effects consist of, activities of daily†¦show more content†¦Doe’s chronic disease of rheumatoid arthritis. This enhanced the interview process as the questions were relatable to the interviewee, this ultimately allowing a higher chance to g ain the information required. The questions were also formed around the papers purpose of daily living, medicine and substance intake and how these link to determinants of health. Lastly the way in which the questions were communicated and adapted strengthened the interview process by ‘determining how the patient can best receive the message’ (Day, Levett-Jones Kenny 2012). The communication was also heightened through the loudness of speech as Mr. Doe has cognitive impairment with hearing. It is important that when interviewing cognitive impaired interviewees that the interview is taken in a quite environment such as a home or office, that you use a firm loud voice, only ask one question at a time, and that the interviewee is given plenty of time to answer each topic and question asked. (Day, Levett-Jones Kenny 2012). This is believed why the six questions asked were appropriate and gained the information required for the papers purpose. Ethics and Codes During the interview with Mr. Doe the ‘Code of Ethics for Nurses in Australia’ was adhered to by the interviewer. This was done in a variety of ways, for example ensuring that the interviewee was aware of the interview process, the topics in which would be covered as well as the privacy that would be

Wednesday, May 6, 2020

Transfer Functions Free Essays

string(141) " Summing point Takeoff point Block Transfer function \+_ The above figure shows the way the various items in block diagrams are represented\." ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ TRANSFER FUNCTIONS AND BLOCK DIAGRAMS 1. Introduction 2. Transfer Function of Linear Time-Invariant (LTI) Systems 3. We will write a custom essay sample on Transfer Functions or any similar topic only for you Order Now Block Diagrams 4. Multiple Inputs 5. Transfer Functions with MATLAB 6. Time Response Analysis with MATLAB 1. Introduction An important step in the analysis and design of control systems is the mathematical modelling of the controlled process. There are a number of mathematical representations to describe a controlled process: Differential equations: You have learned this before. Transfer function: It is defined as the ratio of the Laplace transform of the output variable to the Laplace transform of the input variable, with all zero initial conditions. Block diagram: It is used to represent all types of systems. It can be used, together with transfer functions, to describe the cause and effect relationships throughout the system. State-space-representation: You will study this in an advanced Control Systems Design course. 1. 1. Linear Time-Variant and Linear Time-Invariant Systems Definition 1: A time-variable differential equation is a differential equation with one or more of its coefficients are functions of time, t. For example, the differential equation: d 2 y( t ) t2 + y( t ) = u ( t ) dt 2 (where u and y are dependent variables) is time-variable since the term t2d2y/dt2 depends explicitly on t through the coefficient t2. An example of a time-varying system is a spacecraft system which the mass of spacecraft changes during flight due to fuel consumption. Definition 2: A time-invariant differential equation is a differential equation in which none of its coefficients depend on the independent time variable, t. For example, the differential equation: d 2 y( t ) dy( t ) m +b + y( t ) = u ( t ) 2 dt dt where the coefficients m and b are constants, is time-invariant since the equation depends only implicitly on t through the dependent variables y and u and their derivatives. 1 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ Dynamic systems that are described by linear, constant-coefficient, differential equations are called linear time-invariant (LTI) systems. 2. Transfer Function of Linear Time-Invariant (LTI) Systems The transfer function of a linear, time-invariant system is defined as the ratio of the Laplace (driving function) U(s) = transform of the output (response function), Y(s) = {y(t)}, to the Laplace transform of the input {u(t)}, under the assumption that all initial conditions are zero. u(t) System differential equation y(t) Taking the Laplace transform with zero initial conditions, U(s) Transfer function: System transfer function G (s) = Y(s) Y(s) U(s) A dynamic system can be described by the following time-invariant differential equation: an d n y( t ) d n ? 1 y( t ) dy( t ) + a n ? 1 + L + a1 + a 0 y( t ) n ? 1 dt dt dt d m u(t) d m ? 1 u ( t ) du ( t ) = bm + b m ? 1 + L + b1 + b 0 u(t) m m ? 1 dt dt dt Taking the Laplace transform and considering zero initial conditions we have: (a n ) ( ) s n + a n ? 1s n ? 1 + L + a 1s + a 0 Y(s) = b m s m + b m ? 1s m ? 1 + L + b1s + b 0 U(s) The transfer function between u(t) and y(t) is given by: Y(s) b m s m + b m ? 1s m ? 1 + L + b1s + b 0 M (s) = = G (s) = U(s) N(s) a n s n + a n ? 1s n ? 1 + L + a 1s + a 0 where G(s) = M(s)/N(s) is the transfer function of the system; the roots of N(s) are called poles of the system and the roots of M(s) are called zeros of the system. By setting the denominator function to zero, we obtain what is referred to as the characteristic equation: ansn + an-1sn-1 + + a1s + a0 = 0 We shall see later that the stability of linear, SISO systems is completely governed by the roots of the characteristic equation. 2 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ A transfer function has the following properties: †¢ The transfer function is defined only for a linear time-invariant system. It is not defined for nonlinear systems. The transfer function between a pair of input and output variables is the ratio of the Laplace transform of the output to the Laplace transform of the input. †¢ All initial conditions of the system are set to zero. †¢ The transfer function is independent of the input of the system. To derive the transfer function of a system, we use the following procedures: 1. Develop the differential equation f or the system by using the physical laws, e. g. Newton’s laws and Kirchhoff’s laws. 2. Take the Laplace transform of the differential equation under the zero initial conditions. 3. Take the ratio of the output Y(s) to the input U(s). This ratio is the transfer function. Example: Consider the following RC circuit. 1) Find the transfer function of the network, Vo(s)/Vi(s). 2) Find the response vo(t) for a unit-step input, i. e. ?0 t 0 v i (t) = ? ?1 t ? 0 Solution: 3 R vi(t) C vo(t) ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ Exercise: Consider the LCR electrical network shown in the figure below. Find the transfer function G(s) = Vo(s)/Vi(s). L R i(t) vi(t) vo(t) C Exercise: Find the time response of vo(t) of the above system for R = 2. 5? , C = 0. 5F, L=0. 5H and ? 0 t 0 . v i (t) = ? ?2 t ? 0 4 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ Exercise: In the mechanical system shown in the figure, m is the mass, k is the spring constant, b is the friction constant, u(t) is an external applied force and y(t) is the resulting displacement. y(t) k m u(t) b 1) Find the differential equation of the system 2) Find the transfer function between the input U(s) and the output Y(s). 5 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ 3. Block Diagrams A block diagram of a system is a pictorial representation of the functions performed by each component and of the flow of signals. The block diagram gives an overview of the system. Block diagram items: Summing point Takeoff point Block Transfer function +_ The above figure shows the way the various items in block diagrams are represented. You read "Transfer Functions" in category "Essay examples" Arrows are used to represent the directions of signal flow. A summing point is where signals are algebraically added together. The takeoff point is similar to the electrical circuit takeoff point. The block is usually drawn with its transfer funciton written inside it. We will use the following terminology for block diagrams throughout this course: R(s) = reference input (command) Y(s) = output (controlled variable) U(s) = input (actuating signal) E(s) = error signal F(s) = feedback signal G(s) = forward path transfer function H(s) = feedback transfer fucntion R(s) Y(s) E(s) G(s) +_ F(s) H(s) Single block: U(s) Y(s) Y(s) = G(s)U(s) G(s) U(s) is the input to the block, Y(s) is the output of the block and G(s) is the transfer function of the block. Series connection: U(s) X(s) G1(s) Y(s) G2(s) 6 Y(s) = G1(s)G2(s)U(s) ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ Parallel connection (feed forward): G1(s) + U(s) Y(s) Y(s) = [G1(s) + G2(s)]U(s) + G2(s) Negative feedback system (closed-loop system): R(s) E(s) +_ The closed loop transfer function: Y(s) G(s) Y(s) G(s) = R(s) 1 + G(s) Exercise: Find the closed-loop transfer function for the following block diagram: R(s) Y(s) E(s) G(s) +_ F(s) H(s) 7 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) _______________________________________________________________________________ Exercise: A control system has a forward path of two elements with transfer functions K and 1/(s+1) as shown. If the feedback path has a transfer function s, what is the transfer function of the closed loop system. R(s) +_ Y(s) 1 s +1 K s Moving a summing point ahead of a block: R(s) Y(s) G(s) + R(s) Y(s) +  ± G(s)  ± F(s) 1/G(s) F(s) Y(s) = G(s)R(s)  ± F(s) Moving a summing point beyond a block: R(s) Y(s) + R(s) G(s) Y(s) G(s)  ± +  ± F(s) G(s) F(s) Y(s) = G(s)[R(s)  ± F(s)] Moving a takeoff point ahead of a block: R(s) Y(s) R(s) Y(s) G(s) G(s) Y(s) Y(s) G(s) Y(s) = G(s)R(s) 8 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ Moving a takeoff point beyond a block: R(s) Y(s) R(s) Y(s) G(s) G(s) R(s) R(s) 1/G(s) Y(s) = G(s)R(s) Moving a takeoff point ahead of a summing point: R(s) Y(s) + Y(s)  ± F(s) R(s)  ± F(s) +  ± Y(s) + Y(s) Y(s) = R(s)  ± F(s) Moving a takeoff point beyond a summing point: R(s) R(s) Y(s) + Y(s) +  ±  ± F(s)  ± R(s) F(s) R(s) + Y(s) = R(s)  ± F(s) Exercise: Reduce the following block diagram and determine the transfer function. R(s) + _ + G1(s) G2(s) G3(s) _ Y(s) + + H1(s) G4(s) H2(s) 9 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ Exercise: Reduce the following block diagram and determine the transfer function. H1 + R(s) +_ + G H2 10 Y(s) ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ 4. Multiple Inputs Control systems often have more than one input. For example, there can be the input signal indicating the required value of the controlled variable and also an input or inputs due to disturbances which affect the system. The procedure to obtain the relationship between the inputs and the output for such systems is: 1. 2. 3. 4. Set all inputs except one equal to zero Determine the output signal due to this one non-zero input Repeat the above steps for each of the remaining inputs in turn The total output of the system is the algebraic sum (superposition) of the outputs due to each of the inputs. Example: Find the output Y(s) of the block diagram in the figure below. D(s) R(s) +_ G1(s) + + H(s) Solution: 11 Y(s) G2(s) ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) _______________________________________________________________________________ Exercise: Determine the output Y(s) of the following system. D1(s) R(s) +_ G1(s) + + Y(s) G2(s) H1(s) + + D2(s) 12 H2(s) ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ 5. Transfer Functions with MATLAB A transfer function of a linear time-invariant (LTI) system can be entered into MATLAB using the command tf(num,den) where num and den are row vectors containing, respectively, the coefficients of the numerator and denominator polynomials of the transfer function. For example, the transfer function: G (s) = 3s + 1 s + 3s + 2 2 can be entered into MATLAB by typing the following on the command line: num = [3 1]; den = [1 3 2]; G = tf(num,den) The output on the MATLAB command window would be: Transfer function: 3s+1 ————s^2 + 3 s + 2 Once the various transfer functions have been entered, you can combine them together using arithmetic operations such as addition and multiplication to evaluate the transfer function of a cascaded system. The following table lists the most common systems connections and the corresponding MATLAB commands to implement them. In the following, SYS refers to the transfer function of a system, i. e. SYS = Y(s)/R(s). System MATLAB command Series connection: R(s) Y(s) G1 G2 SYS = G1*G2 or SYS = series(G1,G2) Parallel connection: G1 + R(s) SYS = G1  ± G2 or SYS = parallel(G1, ±G2) Y(s)  ± G2 Negative feedback connection: R(s) Y(s) +_ G(s) SYS = feedback(G,H) H(s) 13 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ R(s) Y(s) +_ G1 G2 H Example: Evaluate the transfer function of the feedback system shown in the figure above using MATLAB where G1(s) = 4, G2(s) = 1/(s+2) and H(s) = 5s. Solution: Type the following in the MATLAB command line: G1 = tf([0 4],[0 1]); G2 = tf([0 1],[1 2]); H = tf([5 0],[0 1]); SYS = feedback(G1*G2,H) This produces the following output on the command window (check this result): Transfer function: 4 ——-21 s + 2 Exercise: Compute the closed-loop transfer function of the following system using MATLAB. R(s) +_ 1 s +1 14 s+2 s+3 Y(s) ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ 6. Time Response Analysis with MATLAB After entering the transfer function of a LTI system, we can compute and plot the time response of this system due to different input stimuli in MATLAB. In particular, we will consider the step response, the impulse response, the ramp response, and responses to other simple inputs. 6. 1. Step response To plot the unit-step response of the LTI system SYS=tf(num,den) in MATLAB, we use the command step(SYS). We can also enter the row vectors of the numerator and denominator coefficients of the transfer function directly into the step function: step(num,den). Example: Plot the unit-step response of the following system in MATLAB: Y (s) 2s + 10 =2 R (s) s + 5s + 4 Solution: Step Response 2. 5 num = [0 2 10]; den = [1 5 4]; SYS = tf(num,den); step(SYS) Amplitude 2 or directly: step(num,den) 1. 5 1 MATLAB will then produce the following plot on the screen. Confirm this plot yourself. 0. 5 0 0 1 2 3 Time (sec. ) 4 5 For a step input of magnitude other than unity, for example K, simply multiply the transfer function SYS by the constant K by typing step(K*SYS). For example, to plot the response due to a step input of magnitude 5, we type step(5*SYS). Notice in the previous example that that time axis was scaled automatically by MATLAB. You can specify a different time range for evaluating the output response. This is done by first defining the required time range by typing: t = 0:0. 1:10; % Time axis from 0 sec to 10 sec in steps of 0. 1 sec and then introducing this time range in the step function as follows: step(SYS,t) % Plot the step response for the given time range, t This produces the following plot for the same example above. 15 6 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) _______________________________________________________________________________ Step Response 2. 5 Amplitude 2 1. 5 1 0. 5 0 0 2 4 6 8 10 Time (sec. ) You can also use the step function to plot the step responses of multiple LTI systems SYS1, SYS2, †¦ etc. on a single figure in MATLAB by typing: step(SYS1,SYS2,†¦ ) 6. 2. Impulse response The unit-impulse response of a control system SYS=tf(num,den) may be plotted in MATLAB u sing the function impulse(SYS). Example: Plot the unit-impulse response of the following system in MATLAB: Y(s) 5 = R (s) 2s + 10 Solution: Impulse Response um = [0 5]; den = [2 10]; SYS = tf(num,den); impulse(SYS) 2. 5 2 impulse(num,den) Amplitude or directly 1. 5 1 This will produce the following output on the screen. Is that what you would expect? 0. 5 0 0 0. 2 0. 4 0. 6 Time (sec. ) 16 0. 8 1 1. 2 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ 6. 3. Ramp response There is no ramp command in MATLAB. To obtain the unit ramp response of the transfer function G(s): multiply G(s) by 1/s, and use the resulting function in the step command. The step command will further multiply the transfer function by 1/s to make the input 1/s2 i. e. Laplace transform of a unit-ramp input. For example, consider the system: Y(s) 1 =2 R (s) s + s + 1 With a unit-ramp input, R(s) = 1/s2, the output can be written in the form: Y(s) = 1 1 1 R (s) = 2 ? s + s +1 (s + s + 1)s s 2 1 ? ?1 =? 3 2 ?s + s + s ? s which is equivalent to multiplying by 1/s and then working out the step response. To plot the unitramp response of this system, we enter the numerator and denominator coefficients of the term in square brackets into MATLAB: num = [0 0 0 1]; en = [1 1 1 0]; and use the step command: step(num,den) The unit ramp response will be plotted by MATLAB as shown below. Step Response 12 10 Amplitude 8 6 4 2 0 0 2 4 6 Time (sec. ) 17 8 10 12 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ 6. 4. Arbitrary response To obtain the time response of the LTI sys tem SYS=tf(num,den) to an arbitrary input (e. g. exponential function, sinusoidal function .. etc. ), we can use the lsim command (stands for ‘linear simulation’) as follows: lsim(SYS,r,t) or lsim(num,den,r,t) here num and den are the row vectors of the numerator and denominator coefficients of the transfer function, r is the input time function, and t is the time range over which r is defined. Example: Use MATLAB to obtain the output time response of the transfer function: Y(s) 2 = R (s) s + 3 when the input r is given by r = e-t. Solution: Start by entering the row vectors of the numerator and denominator coefficients in MATLAB: num = [0 2]; den = [1 3]; Then specify the required time range and define the input function, r, over this time: t = 0:0. 1:6; r = exp(-t); % Time range from 0 to 6 sec in steps of 0. 1 sec Input time function Enter the above information into the lsim function by typing: lsim(num,den,r,t) This would produce the following plot on the screen. Li near Simulation Results 0. 4 0. 35 Amplitude 0. 3 0. 25 0. 2 0. 15 0. 1 0. 05 0 0 1 2 3 Time (sec. ) 18 4 5 6 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ TUTORIAL PROBLEM SHEET 3 1. Find the transfer function between the input force u(t) and the output displacement y(t) for the system shown below. y(t) b1 u(t) m b2 where b1 and b2 are the frictional coefficients. For b1 = 0. 5 N-s/m, b2 = 1. 5 N-s/m, m = 10 kg and u(t) is a unit-impulse function, what is the response y(t)? Check and plot the response with MATLAB. 2. For the following circuit, find the transfer function between the output voltage across the inductor y(t), and the input voltage u(t). R u(t) L y(t) For R = 1 ? , L = 0. 1 H, and u(t) is a unit-step function, what is the response y(t)? Check and plot the result using MATLAB. 3. Find the transfer function of the electrical circuit shown below. R L u(t) y(t) C For R = 1 ? , L = 0. 5 H, C = 0. 5 F, and a unit step input u(t) with zero initial conditions, compute y(t). Sketch the time function y(t) and plot it with MATLAB. 19 ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ 4. In the mechanical system shown in the figure below, m is the mass, k is the spring constant, b is the friction constant, u(t) is the external applied force and y(t) is the corresponding displacement. Find the transfer function of this system. k u(t) m For m = 1 kg, k = 1 kg/s2, b = 0. 5 kg/s, and a step input u(t) = 2 N, compute the response y(t) and plot it with MATLAB. b y(t) 5. Write down the transfer function Y(s)/R(s) of the following block diagram. R(s) Y(s) K +_ G(s) a) For G(s) = 1/(s + 10) and K = 10, determine the closed loop transfer function with MATLAB. b) For K = 1, 5, 10, and 100, plot y(t) on the same window for a unit-step input r(t) with MATLAB, respectively. Comment on the results. c) Repeat (b) with a unit-impulse input r(t). 6. Find the closed loop transfer function for the following diagram. R(s) E(s) Y(s) G(s) +_ F(s) H(s) a) For G(s) = 8/(s2 + 7s + 10) and H(s) = s+2, determine the closed loop transfer function with MATLAB. ) Plot y(t) for a unit-step input r(t) with MATLAB. 7. Determine the transfer function of the following diagram. Check your answer with MATLAB. _ R(s) +_ s s + + 1/s s 20 1/s Y(s) ECM2105 – Control Engineering Dr Mustafa M Aziz (2010) ________________________________________________________________________________ 8. Determine the transfer function of the following diagram. R(s) +_ +_ 50 s +1 Y(s) s 2/s 1/s2 2 +_ a) Check you result with MATLAB. b) Plot y(t) for a unit-impulse input r(t) with MATLAB. 9. Determine the total output Y(s) for the following system. D(s) How to cite Transfer Functions, Essay examples

Wednesday, April 29, 2020

The Glass Menagerie by Tennessee Williams Reality vs. Illusions

The introduction: the fundamentals of the play When discussing one of the most famous plays written by Tennessee Williams, I would like to consider the fundamentals of the work. So, first of all, I would like to define the key themes.Advertising We will write a custom critical writing sample on The Glass Menagerie by Tennessee Williams Reality vs. Illusions specifically for you for only $16.05 $11/page Learn More Generally, one is to keep in mind that popular work discloses ten major themes, namely illusion vs. reality (the theme I want to highlight in detail), memory, freedom, quest, instinct vs. civilized behaviors, famous American Dream, a person’s survival in the machine age, fragility vs. strength, and a person’s need to be far away from his or her surrounding. While speaking about the first theme, illusion vs. reality I have to point out that the play explores a family that lives in shadow of reality. The playwright Williams Tennessee alludes from his early life to write an explicit play focusing on the social lives of specific individuals. Amanda is a mother of two adult children Tom and Laura. After her husband abandoned her, Amanda struggles to take care of the family. Unfortunately, besides suffering from a mental instability Laura is also crippled. Therefore, Tom has a job at shoe warehouse to provide for the family. Consequently, the three members of the family become engrossed in illusions, an aspect, which separates them from the real world. In my opinion, the so-called illusions help the main characters escape unpleasant reality. I suppose it is loss of psychological space what makes the characters to realize that it is impossible to escape the realities of the real world. Dipa Janardanan is of the opinion that the author is able â€Å"to get to the marrow of a universal truth – the human condition of an individual’s inability to escape a psychological loss of space no matter how much phy sical distance is attained† (24). I have to admit that the playwright uses innovative production techniques, in order to draw the readers’ attention to the conflict between illusion and reality. Moreover, the author showed us that the so-called survival mechanisms family decided to rely on were transformed into destructive power. The thesis statement One of the major themes of the play is considered to be the characters’ inability to meet the reality. Taking into account the attitude of all characters towards the realities of life, one can make a conclusion that the main characters require objectivity. No one is ready to accept the reality because it is really painful. While considering such complex psychological situation, it becomes evident that psychological loss of space seems to be one of the key problems the author highlights in his play.Advertising Looking for critical writing on american literature? Let's see if we can help you! Get your first paper with 15% OFF Learn More Tennessee Williams and his story I would like to tell a few words about the author of the play. Generally, there is a need to point out that the author’s father was an adventurous and an alcoholic, his mother was a submissive but hysterical woman. Tennessee spent the first ten years of his life living with his grandparents. His health deteriorated an aspect that did not only make him shy but also contributed to his social weakness (shy). Due to constant relocation and social/financial instability, Williams and his sister became close. However, after sometime Rose suffered from a mental breakdown a development that equally traumatized Williams. Similarly, Tennessee acquired poor social skills and most of his peers referred to him as ‘Miss Nancy’ (Londre 20). Education wise, he did not finish his first degree after failing his exams in the third year. However, after acquiring literary skills from his grandfather’s library, th e author embarked on writing plays. Most of his plays were a reflection of his early life. He focused on themes such as sexual violence, social misfit, family and financial constraints among others. Tennessee wrote the play glass menagerie when the Second World War was about to end. Consequently, most spouses (men) had abandoned their families and ventured into the war therefore, creating a social gap. The body: the ways the characters reject the reality Amanda Wingfield who is one of the main characters of the play doesn’t live, but exists. Socially, Amanda’s husband abandoned her, leaving her with the financial and emotional burden to take care of the family. Amanda longs for financial and social success but this element makes her to adopt an illusionary life. Secondly, Amanda declines to accept the exit of her husband from the family thus, acquiring a domineering and hysterical attitude especially towards the children. For instance, Amanda says, â€Å"Gone, gone, g one. All vestige of gracious living! Gone completely! I wasn’t prepared for what the future brought me† (Williams 694-696). This shows that Amanda has declined to let her past go and accept the reality. So, this is an example of illusion. Unfortunately, Amanda can’t face the realities of life. When analyzing the play, it becomes evident that in real life â€Å"Williamses were never as hard up as the fictional Wingfields and so, without denying the effect of the general socio-economic environment as an intensifying element, I tend to see Amanda’s insecurity as characteristic of the alcoholic’s family† (Debusscher 59).Advertising We will write a custom critical writing sample on The Glass Menagerie by Tennessee Williams Reality vs. Illusions specifically for you for only $16.05 $11/page Learn More While speaking about the second character – Laura, I have to point out that the girl lives in an illusionary wor ld. According to Williams, Laura has â€Å"Little articles of [glass], they’re ornaments mostly! Most of them are little animals made out of glass, the tiniest little animals in the world. Mother calls them a glass menagerie!† (547). Therefore, Laura distances herself from the real world. According to Joven, Laura is â€Å"like a piece of her own glass collection, too exquisitely fragile† (57). Consequently, Laura is using both her physical and mental disability to detach herself from realism. The third character is Tom. He struggles to balance his family’s responsibility as the breadwinner thus, trying to escape from the reality. According to Williams, Tom says, â€Å"There is a trick that would come in handy for me—get me out of this two-by-four situation!† (680). Although Tom is narrating a movie to Laura, his mind is struggling to devise ways in, which he can run away from home and offload the responsibility burden that always awaits him . Furthermore, he visits bars and theatres in order to stay away from home. However, Tom’s actions are unreal because he is the only male figure in the family. However, abandoning his family means running away from the real aspects of life thus, he is living in fantasy. The movie is only an illusionary step that in reality it is hard to accomplish. For instance, he says, â€Å"I am more faithful than I intended to be!†(Williams 682). This statement shows that Tom finds it unreal to abandon his sister and mother therefore, his dream of pursuing adventure away from home is only illusionary. Similarly, according to critics, Tom’s â€Å"nature is not remorseless and to escape from trust he has to act without pity† (Broom 20). However, he finally deserts his family when he loses his job. Therefore, Tom lives with an illusion that if he stays alone then he may have a comfortable life. Conclusion: reality vs. illusion In brief, Williams play focuses on the lives of three family members, who lack social skills thus; they become caught between realism and fantasy.Advertising Looking for critical writing on american literature? Let's see if we can help you! Get your first paper with 15% OFF Learn More Although Amanda’s husband left her with the family responsibilities, she is reluctant to accept her situation. She lives under the American dream whereby everybody should have a comfortable life. In addition, she reflects on her early life whereby her family was rich. Surprisingly, she confers her son with financial responsibility a step, which motivates him to dream of how to abandon his family. Finally, due to her physical disability, Laura detaches herself from other people and become engrossed with her glass menagerie. Therefore, all the three characters have to come out of their cocoons in order to face the real world. Works Cited Bloom, Harold. Tennessee Williams’s (Bloom’s Modern Critical Interpretations): The Glass Menagerie. New York: Chelsea House Publishers, 2007. Print. Debusscher, Gilbert. Tennessee Williams’s Dramatic Charade: Secrets and Lies in The Glass Menagerie, 2000. Web. Janardanan, Dipa. Images of Loss in Tennessee Williams’s The Glass Menagerie, Arthur Miller’s Death of a Salesman, Marsha Norman’s night, Mother, and Paula Vogel’s How I Learned to Drive, 2007. Web. Joven, Nilda. â€Å"Illusion Verses Reality in The Glass Menagerie.† Diliman Review 1.1(1966): 52-60. Print. Londre, Hardison. Tennessee Williams. New York: Frederick ungar publishers, 1979. Print Williams, Tennessee. The glass menagerie. New York: Random house, 1950. Print. This critical writing on The Glass Menagerie by Tennessee Williams Reality vs. Illusions was written and submitted by user Phoenix Vazquez to help you with your own studies. You are free to use it for research and reference purposes in order to write your own paper; however, you must cite it accordingly. You can donate your paper here.