John Keats: Ode On A Grecian Urn

John Keats: Ode On A Grecian Urn Thou still unravishd bride of quietness[im1], Thou foster-child [im2]of silence and slow time, Sylvan [im3]historian, who canst thus express A flowery [im4]tale more sweetly[im5] than our rhyme: What leaf-fringd legend haunts[im6] about thy shape Of deities or mortals, or of both,[im7] In Tempe [im8]or the dales of Arcady[im9][im10]? What men or gods are these? What maidens loth? What mad pursuit? What struggle to escape?[im11] What pipes and timbrels? What [im12]wild ecstasy? Heard melodies are sweet, but those unheard[im13] Are sweeter; therefore, ye soft pipes[im14], play on; Not to the sensual ear, but, more endeard, Pipe to the spirit ditties of no tone[im15]: Fair youth, beneath the trees, thou canst not leave Thy song, nor ever can those trees be bare;[im16] Bold[im17] Lover, never, never canst thou kiss, Though winning near the goal yet, do not grieve; She cannot fade[im18], though thou [im19]hast not [im20]thy bliss, For ever wilt thou love, and she be fair![im21] Ah, happy, happy [im22]boughs! that cannot shed Your leaves, nor ever bid the Spring adieu; And, happy melodist, unwearied[im23], For ever piping songs for ever new;[im24] More happy love! more happy, happy love! For ever warm and still to be enjoyd, For ever panting[im25], and for ever young; All breathing human passion far above[im26], That leaves a heart high-sorrowful and cloyd[im27][im28], A burning forehead, and a parching tongue. Who are these coming to the sacrifice? To what green altar, O mysterious priest, Leadst thou that heifer lowing at the skies, And all her silken flanks with garlands drest? What little town by river or sea shore, Or mountain-built with peaceful citadel[im29], Is emptied of this folk, this pious morn? And, little town, thy streets for evermore Will silent be; and not a soul to tell Why thou art desolate, can eer return. O Attic shape! Fair attitude! with brede Of marble men and maidens overwrought[im30], With forest branches and the trodden weed; Thou, silent form[im31], dost tease us out of thought As doth eternity: Cold Pastoral![im32] When old age shall this generation waste, Thou shalt remain, in midst of other woe Than ours, a friend to man, to whom thou sayst, Beauty is truth, truth beauty[im33],-that is all Ye know on earth, and all ye need to know. Background: Keats felt inspired after reading two Benjamin Haydon articles, he was aware of Greek art and he had first hand exposure to the Elgin marbles. Reinforced his belief that Greek art was idealistic and captured Greek virtues which form the basis of the poem. He wrote the Odes when he left his job as assistant house surgeon in London, to devote himself entirely to the composition of poetry. Living with his friend Charles Brown, the 23-year-old was burdened with money problems and despaired when his brother George sought his financial assistance. Relationships between the soul, eternity, nature, and art. Keats was a second generation of Romantic poet, he took a polite subject a study of a Greek pot commonly spoken about by the Augustans and traditional odes and turned it into a loud, over-the-top celebration of music, sex, and youth. Structure: Attempted to write sonnets but found the rhyme scheme did not match the message he was trying to convey, so he turned to the ode form. But he found the Pindaric form inadequate for discussing philosophy. So, he developed his own kind. Further altered his ode style for Nightingale and Grecian Urn by adding a secondary voice- creating a dialogue. Keats uses ekphrasis, (the poetic representation of a painting or sculpture in words) but differently from Theocrituss Idyll, a classical poem describing a design on the side of a cup, Theocritus describes motion and underlying motives whilst Keats focuses solely on the external features of the cup but makes the reader think about the underlying motives. Ten-line stanzas, beginning with an ABAB rhyme scheme (alternate rhyme) and ending with a Miltonic sestet (1st and 5th stanzas CDEDCE, 2nd stanza CDECED, and 3rd and 4th stanzas CDECDE, the Keatsian Structure). The same overall pattern is used in Ode on Indolence, Ode on Melancholy, and Ode to a Nightingale (though their sestet rhyme schemes vary), which unify the poems in structure as well as theme. Creates the sense of a two-part thematic structure as well. The first four lines of each stanza roughly define the subject of the stanza, and the last six roughly explicate or develop it. Ode in Greek, means sung. While ode-writers from antiquity adhered to rigid patterns of strophe, antistrophe, and epode, the form by Keatss time had undergone enough transformation that it represented a manner rather than a set method for writing a certain type of lyric poetry. Keatss odes seek to find a classical balance between two extremes, and in the structure of Ode on a Grecian Urn, classical literature and the asymmetry of Romantic poetry. The use of the ABAB structure in the beginning lines of each stanza represents a clear example of structure found in classical literature, and the remaining six lines appear to break free of the traditional poetic styles of Greek and Roman odes. Keats metre reflects a conscious development in his poetic style. The poem contains only a single instance of medial inversion (the reversal of an iamb in the middle of a line), which was common in his earlier works. Keats incorporates spondees in 37 of the 250 metrical feet. Caesurae are never placed before the fourth syllable in a line. The word choice represents a shift from Keats early reliance on Latinate polysyllabic words to shorter, Germanic words. In the second stanza, Ode on a Grecian Urn, which emphasizes words containing the letters p, b, and v, uses syzygy, the repetition of a consonantal sound. The poem incorporates a complex reliance on assonance, which is found in very few English poems. Line 13 where the e of sensual connects with the e of endeard and the ea of ear connects with the ea of endeard. A more complex form is found in line 11 the ea of Heard connecting to the ea of unheard, the o of melodies connecting to the o of those and the u of but connecting to the u of unheard. Themes: Like many Keatsian odes, Ode on a Grecian Urn discusses art and arts audience. He relied on depictions of natural music in earlier poems, and works such as Ode to a Nightingale appeal to auditory sensations while ignoring the visual. Keats reverses this when describing an urn within Ode on a Grecian Urn to focus on representational art. He previously used the image of an urn in Ode on Indolence, depicting one with three figures representing Love, Ambition and Poesy. Of these three, Love and Poesy are integrated into Ode on a Grecian Urn with an emphasis on how the urn, as a human artistic construct, is capable of relating to the idea of Truth. The images of the urn described within the poem are intended as obvious depictions of common activities: an attempt at courtship, the making of music, and a religious rite. The figures are supposed to be beautiful, and the urn itself is supposed to be realistic. Although the poem does not include the subjective involvement of the narrator, the description of the urn within the poem implies a human observer that draws out these images. The narrator interacts with the urn in a manner similar to how a critic would respond to the poem, which creates ambiguity in the poems final lines: Beauty is truth, truth beauty, that is all / Ye know on earth, and all ye need to know. The lack of a definite voice of the urn causes the reader to question who is really speaking these words, to whom they are speaking, and what is meant by the words, which encourages the reader to interact with the poem in an interrogative manner like the narrator. The urn, as a piece of art, requires an audience and is in an incomplete state on its own. This allows the urn to interact with humanity, to put forth a narrative, and allows for the imagination to operate. The images on the urn provoke the narrator to ask questions, and the silence of the urn reinforces the imaginations ability to operate. This interaction and use of the imagination is part of a greater tradition called ut pictura poesis the contemplation of art by a poet which serves as a meditation upon art itself. In this meditation, the narrator dwells on the aesthetic and mimetic features of art. The figures on the urn within Ode on a Grecian Urn lack identities, but the first section ends with the narrator believing that if he knew the story, he would know their names. The second section of the poem, describing the piper and the lovers, meditates on the possibility that the role of art is not to describe specifics but universal characters, which falls under the term Truth. The three figures would represent how Love, Beauty, and Art are unified together in an idealised world where art represents the feelings of the audience. The audience is not supposed to question the events but instead to rejoice in the happy aspects of the scene in a manner that reverses the claims about art in Ode to a Nightingale. Similarly, the response of the narrator to the sacrifice is not compatible with the response of the narrator to the lovers. Narrator contemplates where the boundaries of art lie and how much an artist can represent on an urn. The questions the narrator asks to reveal a yearning to understand the scene, but the urn is too limited to allow such answers. Furthermore, the narrator is able to visualise more than what actually exists on the urn. This conclusion on art is both satisfying, in that it allows the audience to actually connect with the art, and alienating, as it does not provide the audience the benefit of instruction or narcissistic fulfilment. Besides the contradictions between the various desires within the poem, there are other paradoxes that emerge as the narrator compares his world with that of the figures on the urn. In the opening line, he refers to the urn as a bride of quietness, which serves to contrast the urn with the structure of the ode, a type of poem originally intended to be sung. Another paradox arises when the narrator describes immortals on the side of an urn meant to carry the ashes of the dead. In terms of the actual figures upon the urn, the image of the lovers depicts the relationship of passion and beauty with art. In Ode to a Nightingale and Ode on Melancholy, Keats describes how beauty is temporary. However, the figures of the urn are able to always enjoy their beauty and passion because of their artistic permanence. The urns description as a bride invokes a possibility of consummation, which is symbolic of the urns need for an audience. [im1]Apostrophe: Silences the Urn and projects a voice, his own onto it allowing him to speak on its behalf. [im2]Married to Mr. Quietness but they have never consummated their marriage despite ravished imagery. Also, adopted by silence and time but these were not the originally circumstances, the true parent is the silent painter and ceremonial use. After the decline on Greece the pot continued to live on. [im3]Means Forest, the Urn is a historian of people of the woods. [im4]As well as the bee imagery flowery is a pun as a flowery tale is very complicated, also an urn had a flowery or leafy border. [im5]Flower and sweetly is metaphor for bees and nature, he believes that the Urn can tell a better story, with nature like unlike poetry, both are true beauty and show nature. [im6]Exist in one place- but has obvious connections to the supernatural and the dead characters. [im7]In ancient Greece Gods were represented as normal people so it would be hard to tell the difference, Gods also liked to be in company with people. In a way, the poems rigid rhyme and meter is very understated bringing parallels to God. Effortless on the surface highly intricate underneath you wouldnt know what you were looking for unless you sough it out.. [im8]The Vale of Tempe was home for a time to Aristaeus, son of Apollo and Cyrene, and it was here that he chased Eurydice, wife of Orpheus, who, in her flight, was bitten by a serpent and died. In the thirteenth century AD a church dedicated to Aghia (Saint) Paraskevi was erected in the valley. [im9]Tempe and Arcady are allusions to two regions of Ancient Greece known for being particularly lush and green. They become stock symbols in English poetry for places where people lived in the forest. [im10]Vision of pastoralism in nature. [im11]USE of ekphrasis, the poetic representation of a painting or sculpture in words. [im12]Repetition of questions (anaphora) that the speaker cannot comprehend draws parallels to the interaction between Job and God. Something that is godly like nature or beautiful art is incomprehensible for man we can do our best to try to understand it only. [im13]ASSONANCE: ea of Heard connecting to the ea of unheard, the o of melodies connecting to the o of those and the u of but connecting to the u of unheard. [im14]Unlike the wild party music in the chase in stanza 1 the soft pipes give a soothed atmosphere [im15]Paradox: the sweetest melodies are the ones that you do not hear. Keats is tricking the audience: he treats the people as if they are real people in real events living on the Urn just in frozen time The Urns beauty allows him to think of a song in his head that the man is playing and its more beautiful than anything that he has ever heard before. Aka he prefers the fantasy world to the real one. [im16]Edenic, it shall always be spring here with the man under the tree always playing his sweet music for his spirit. [im17]Another apostrophe [im18]No surprise that he is so obsessed with immortality, he had just contracted TB.. [im19]Greece had connections to higher society and was rebellious, he uses anachronistic diction to make this connection with the constant repetition of thou- its made to sound fancy. [im20]Keats says not to grieve but continues to use negative phrasing even in these lines: do not grieve, cannot fade, and hast not thy bliss. Keats may have made a mistake, or there may be a reason for this negative undertone [im21]SYZYG: Repetition of the consonant sound b v p in particular, breaking his reliance on Latinate polysyllabic words to shorter, Germanic words. [im22]Potentially trying to convince himself that he is happy allegorically he is actually happy. [im23]Pronounced un-wear-i-ed to preserve the iambic pentameter. Potentially comparing himself to the happy melodist who too draws out notes/syllables. [im24]Stuck in the same time forever its always new nothing shall ever grow old. [im25]Repetition shows the eternal nature of the urn which is observed here. Panting from being chased in S1 as well as sexual connotations. Alternatively, with the rhythm pulsating and the repetition of speech he is growing sexually excited himself. [im26]Could be the speaker standing above the urn or it could suggest that the lovers are better of above human passion and they are actually all Gods, preserved and beautiful- living on forever as long as they are remembered. [im27]If it is the speaker standing high above then it must be his heart that is sorrow filled, looking at those in love sadden him. Uses metonym to connect them. Words that give meaning to another i.e. Westminster = House of Parliament, Downing Street = Prime Minister. [im28]Too much of something good. [im29]Oxymoron peaceful fortress [im30]Overcomplicated- too good for us Godly. [im31]Apostrophe and personificationÂÂ   is cyclical like looking around the urn in a circle. [im32]The poet compares the experience of looking at the urn to thinking about eternity, an idea so lofty and hard to understand that trying to think about it is like not thinking at all. [im33]Simple chiasmus acts as synecdoche for the poem. Due Process and Crime Control Models: Compare and Contrast Due Process and Crime Control Models: Compare and Contrast The purpose of this paper is to research both the Due Process and Crime Control Models. After researching each of the topics, they will be discussed in further detail. Both of the models will be compared and contrasted as well. Both of the models have proven to be well known and used throughout the United States, as well as many other parts of the world; both models have been used since the 1960s. The contemporary state court system status and the model that is used there will be discussed further in the paper. Both of the models named above are very complex systems that are used in criminal justice systems throughout the United States as well as many other parts of the world. The models were developed as some type of guideline to aid in the arrest and prosecution of criminals. The purposes of the two models are to help maintain safety is society, as well as protect the rights of the suspect in various situations and scenarios. In order to fully understand both of the models, each system must be viewed separate and together. Various models and techniques have been used in the criminal justice system since its development, some of the models have been more structured than others, some have been less structured than others. When evaluated, some of the different models have worked well in some areas, while other models have not appeared to be beneficial at all. Literature Review Choongh (1998) provided readers with information regarding the limitations of Packers crime control and due process models, which were developed in the 1960s. Choongh informed readers that the crime control model follows procedures very closely, as well as screen suspects, determines guilt, and secures punishment all according to written policies, procedures, and laws. Choongh suggested that there are some problems with the model. One of the problems is that the model defines efficiency by speed and finality. This could possibly be beneficial in some ways, but could also cause harm in other ways; the quicker the investigation the more likely that the work may be incomplete or sloppy. The due process model is more concerned with individual integrity and autonomy. The main purpose of the due process model is to maintain close control over the power of the state. Choongh reported that neither model is effective, this is because the investigations are not thorough enough, court processes are rushed, and prosecutors and law enforcement rush to accusing a person of guilt rather than taking their time and finding the real villain. Henham (1998) provided readers with information about the rights-based approach. The author explained that there is a large need for a rights-based approach to be used for criminals during the sentencing process. Henham feels that the crime control model and the due process model are not adequate. The crime control model is based on repressing criminal activity and maintaining a low crime rate. The due process model focuses mainly the protection of the individual through stressing adherence to courtroom procedures. The rights-based approach is concerned to postulate a number of fundamental normative propositions that have moral, rather than empirical validity. The crime control model and the due process model do not provide adequate choices to criminals when mental health problems are involved, but a rights-based approach would address several areas that the other models do not address. Henham felt that people who suffer from different mental disorders are essentially being discrimin ated against, by not providing for their need. Schrieber, Renneberg, and Macracker (2009) and Tucker, Hasselt, and Russell (2008) all wrote about the criminal justice system, mentally ill patients, and the professionals inadequate training for dealing with the mentally ill. All of the above authors agreed that there is a great need for special training and possibly special crime models that should be used when police are dealing with mentally ill criminals. Recently there has been a rise in the number of cases that law enforcement officials have responded to in which mentally ill individuals were the reason the police were called. Schrieber, Renneberg, and Macracker reported that the criminal justice system is not capable of dealing with offenders who suffer from mental disorders that uncontrollable. Recent studies have shown that law enforcement officials have are generally the first contact with mentally ill suspects in criminal cases, but also in many cases that are not criminal and have to be dealt with through social service programs. The authors reported that the models need to be reorganized so that the criminal justice system will be more sensitive to individuals who suffer from major depression, post traumatic stress disorder, schizophrenia, and psychosis. Rehabilitation is very important for individuals who have these disorders and the treatment that they need is not offered in many of the detainment facilities that criminals are sent to. Klein (2006) wrote about the crime control model. She reported that the crime control model has a very reliable process for screening suspects, and many of the criminals that are charged with crime using this model, will spend time in jail or prison, because the system is so reliable. Klein also wrote about the due process model and how it helps an individual to maintain some autonomy during the criminal justice process. Even though there is room for improvement in the areas of pleading and discovery, Klein supports most of the aspects in each model and the basis behind them. Duff (1998) wrote about the crime control model and the due process model and how the models are viewed in the criminal justice system. Duff reported that the due process model does not agree with the majority of cases in which criminal are sanctioned for their crimes, this is because if the crimes do not involve any harm to others, Duff feels that the criminal should be punished les severely. Roach (1999) provided readers with information about four different models used in the criminal justice system. Roach directed more attention to the due process model and the crime control model. Roach explained Herbert Packer provided professionals with a guide to criminal justice systems by using these models. Both of the authors reported that if the crime control model is used correctly, most criminals plead guilty to the charge or the prosecuting attorney withdrawals the charges. Roach, as well as Duff reported that both models were not only efficient, but also very durable in order to with stand as many years as they have. Edkins (2007) provided readers with information about the due process model and its purpose of helping suspects maintain their individual rights during the criminal justice process. Edkins also provided readers with information about the crime control model and its purpose of making sure that all convicted criminals have harsh punishments. Edkins gave information about seven different studies that were completed which measured attitudes about the due process and crime. Vance and Trani (2008) conducted numerous studies on the crime control model and the due process model. The authors are not in agreement with the crime control model, but they do support the due process model. Vance and Trani reported that both of the models have ethical standards and should be supported across the board, but the in some places, law enforcement and prosecuting attorneys will not support either of the models. The authors reported that there are many reasons for different crime models, some of these purposes are to help catch criminals, detain them, and reduce crime. Arias and Ungar (2009) wrote about Latin Americans and the impact that the two models have on their lifestyle. The authors informed readers that the purpose of the crime control mode is to reduce crime and the purpose of the due process model is to protect individual rights of the accused when it is used as a guide for the criminal justice process. Discussion Due Process The basis of the due process model is formal structure. When used correctly, the due process model protects the rights of suspects accused of various crimes. The due process model reduces many errors that occur during the investigation, arrest, evidence gathering, and trial. Due process does not support much of the evidence that is used in many criminal trials, and there are many reasons and factors for this. Basically, the due process model criticizes every type of evidence except definitive physical evidence that cannot be disputed. The object of looking at evidence in the due process model is deciding what information may be incorrect, falsified, or coerced from an individual. This has occurred on many occasions when other criminals have testified against the suspect, because they may be rewarded with time off of their sentence or other things. Because the main goal of the due process model us to reduce mistakes that can place an innocent person in prison, the process is very slow (Henham, 1998 Klein, 2006). Crime Control The idea of the crime control model is to decrease crime in all areas; for this to be done criminal conduct needs to be drastically reduced. Many of the problems that arise in the crime control model is directed at law enforcement officials. People commit crimes and get away with them, then it may create a higher crime rate because their likely to be more followers. The crime control model directs more attention in investigating, screening people, establishing guilt, seeking harsher punishments for individuals who have committed crimes (Roach, 1999). For the crime control model to work appropriately, the processes must be efficient. Higher arrest and conviction rates need to be seen, as a way of deterring other people from committing crimes. The investigation and arrest process needs to be expedient, so that fewer resources are used on each client. The main purpose of the crime control model is for the there to be enough evidence gathered that the suspects pleads guilty to the charges, and there is no need to waste time, money, or effort on a trial that may last for a unknown amount of time (Duff, 1998). The crime control model utilizes law enforcement officials and prosecuting attorneys to establish the innocence or guilt of a suspect early during the investigation. Individuals who are most likely guilty of committing such crimes progress through the criminal justice systems with great speed; they either plead guilty to such crimes, or they are found innocent or guilty in a criminal trial. , the less likely to find the evidence needed, and the more money spent on the investigation (Klein, 2006). Similarities and Differences between the Two Models The main goal of the due process model is for individuals to be treated fairly in the criminal justice system, so they will not be deprived anything that they deserve in life of they are innocent. The due process model explains that all individuals have a right to freedom and security, unless they are guilty of committing a crime. The crime control model does not hold an individuals rights in high regard, and feels that criminals should be caught at all cost (Roach, 1999). The crime control model puts a lot of their trust into law enforcement officials and prosecuting attorneys to complete the criminal investigations. Depending on the amount of work put into the investigation and the quality of the work that is done, many suspects will either plead guilty, therefore there is no trial. Speed and finality two tasks the crime control model looks to complete (Roach, 1999). When people are arrested for a crime, they are seen as innocent until they actually admit to or are convicted of such crimes (Klein, 2006). When dealing with the due process model, policing society in a positive nature becomes a very vital issue. Followers of the crime control model feel that the number of arrests may deter other criminals from committing crimes, by showing them that the criminal justice system does work (Klein, 2006). Much of the population is in favor of the due process model, because of reasons such as equality, human rights, and freedom. Undert the United States Constitution each individual has certain rights, and the due process model helps to maintain and restore these rights (Henham, 1998). Law enforcement agencies generally prefer the crime control model; they treat suspects who are arrested as though they have already been found guilty (Henham, 1998). The due process model protects individuals with the 4th and 8th amendments which address the issues of illegal searches on individuals suspected of crimes, as well as the right not to incriminate ones self (Choongh, 1998). State Court Systems Model of Choice It appears that each of the models are very unique and are used for different purposes. Just as different defense attorneys have different styles and models that they follow, so do law enforcement officials and prosecuting attorneys. The model that is used is completely up to the individual who is gathering the information and investigating the crime. In an ideal world, the due process model would be the model of choice, because it helps keep the rights of individuals intact, as well as serving its purpose in the criminal justice system. Both the crime control model and the due process model have a positive side as well as a negative. The United States criminal justice system and judicial system has debated the subject of which models are the most beneficial for numerous years, but no common ground has been reached. Two of the main factors that are looked at when making a decision such as this are, which model helps maintain social order, and which model helps reduce the risk of imprisoning innocent individuals. As close as these two factors are related, the answer should be simplistic, however it is not. In the criminal justice system, these factors actually conflict with one another, therefore there is not a common system that came be used for both of the factors. Maintaining and restoring social order is best maintained by the crime control model, whereas protecting individual rights is best maintained by the due process model (Edkins, 2007). The population that law enforcement officials are serving may affect the crime model that they decide to use. Areas with high crime rate may be better served by using the crime control model, whereas areas with less crime may be better served by the due process model. Along with the population, the type of crimes that are being committed may also be a factor in which model is chosen. Areas that suffer from drug trafficking and violence may be best served by using the crime control model, whereas areas that suffer from trespassing and burglaries may be best served by using the due process model. The crime control model implies that law enforcement and prosecuting attorneys act promptly to allegations and investigate them more thoroughly at a later time, but the due process model requires careful consideration in each and every case, prior to arresting individuals (Duff, 1998). Conclusion Both of the models have very different key points. Both of the models have different methods that are used to reach a common goal. If the main goal of the United States Criminal Justice System is to maintain social order and protect the rights of individuals, then there is no way to utilize just one of the two models. The crime control model appears to be the best model used for maintain and restoring order in society. In the ideal world, decisions would not be made in haste. But in order to complete a job and catch certain criminals, then there has to be room for quick decisions, even if it becomes clear that the decisions that were made were wrong. Each state, county, and city has their own way of operating and reducing crime. Unfortunately at times innocent people are brought into the mix, this is a chance that has to be taken in order to have a fully functioning criminal justice system. Scholars have researched for many years how to make the criminal justice system work by following one model, but at this time nobody has been successful in developing such a model. Family: Social Construct And Institution Family: Social Construct And Institution In this essay I intend to discuss the family as a social construct and institution. I will be critically discussing the different forms of the family, and the role of the family within society from four sociological perspectives. The family as a social structure is often taken for granted to mean a married couple with children, possibly incorporating grandparents and directly linked blood relatives. This stereotypical view does not take into account a changing society with changing norms and values. It is important when discussing the family in a sociological context to define the family in a wider perspective. Ferrante (2011) suggests that the family is often described as a social institution that binds people together through various means, blood, marriage, norms and law. According to Zelditch (1964) as cited in Ferrante (2011) there is no concrete group which can be universally identified as the family. Several institutions including political parties, the legal system and the media have been blamed for creating the cereal packet family but not all sociologists agree with what appears to be typical British family. Gittins (1993) as cited in Marsh and Keating (2006) states The ideology of the family would have us believe that there is one type of family, one correct way in which individuals should live and interact with each otherAn ideology that claims that there is only one type of family can never matched in reality, for it represents an ideal to which only some can approximate, an others not at all. During the last century the concept of the family has altered, this is partly due to industrialisation, modernity, changing norms and values and the media. The family can now be seen to have many dimensions, what was considered to be deviant or diverse is often accepted as a norm. Some sociologists argue that during the nineteenth century, post industrialisation, social order, or kinship, a network of relatives (kin) who are connected by common decent or marriage. (Fulcher and Scott 2007) began to alter. Communities that were based on traditional shared values of religion and community changed. Cottage industries began to disappear and families moved from rural areas into towns and cities the nature of the of kinship began to diminish. The economic and social life of this type of family relationship changed, according to Ritzer and Ryan (2011) Rural people were lured by the novelty of city life and the prospects of greater economic opportunity. The domestic economy of the pre-industrial family disappeared. The industrial revolution provided factory work for men leaving the females to take a more prominent role as the caregivers, the family dynamics began to alter creating a major change in the division of labour within the family. Industrialisation was identified by many as having sounded the death knell for this way of life, destroying extended families and undermining communities. (Ogburn 1955 as cited in Gillies 2003). The extended family tends to include generations of family extending both horizontally and vertically including connections my marriage and blood. It is argued by some sociologists that industry has destroyed the traditions of the extended family and the social bonding of kinship, leading to the nuclear family. Talcott Parsons (1949) as cited in Fulcher and Scott (2007) stressed that in the absence of the extended family and kinship, the nuclear family met the needs of a changed society. However Laslett and Wall (1972) as cited in Fulcher and Scott (2007) suggest that the nuclear family has always been the more dominant family type throughout the history of family life. The functionalist approach to the family suggests that the family itself is responsible for ensuring that vital tasks are achieved. Functionalists believe that social institutions such as schools, churches, political systems and the family are all essential to the structure of an effective functioning society and all of these institutions inter relate with each other for the benefit of the whole of society, if one aspect of the structure does not function adequately then society will inevitably experience some form of failure and conflict. Functionalists suggest that the family is one of the most important institutions responsible for the successful raising of a child and parents play a key role in ensuring that children become well integrated within society. Murdock (1949) conducted a study based on two hundred and fifty societies with the aim of discovering if the family was universal. His conclusion was that the nuclear family was a universal social institution that comprised of four basic functions. These he called, sexual relationships, economic cooperation among members, reproduction and the socialisation of infants and children. (Stark, 2010) Murdocks theory has been criticised by many non functionalist sociologists suggesting that his study focussed on the nuclear family and did not take into account other family forms. Gough (1959) argued that Murdocks theory did not take into account societies such as the Nayar, where one woman could have up to twelve potential fathers to a child and a man could have an unlimited amount of wives. Support came from brothers, sisters and children not from potential fathers. This system was based purely on kinship groups. Gough suggests that the existence of the Nayar was not based on economic cooperation between husbands and wives, the socialisation of infants was provided by the women and their kinship groups, and any affectionate relationship between men and women was prohibited. Goughs criticism can be closely compared to family groups in British society today looking at family units that do not meet Murdocks nuclear family theory these families could be single parent families or fami lies consisting of same sex couples. (Bell 1968) Parsons (1959) as cited in Macionis (2012) argued that the family retains two primary functions, these functions are found in all forms of family thought out the world. He suggests that the primary socialisation of children is the first and most important setting for child rearing and parents are in the position to ensure children are able to become well integrated into society and the structuring of the personality in the early years leads to contributing members of society. He acknowledges that family socialisation continues throughout the life cycle but secondary socialisation becomes more dominant as the child develops due to the family being less involved, and agencies such as schools and peer groups become involved. Parsons as cited in Harolambos and Holborn (2008) argued that families are factories which produce human personalities. Parsons second observation of the family was the stabilisation of the adult personality arguing that men and women who have deep personal relationships will lead content and fulfilling lives which in turn will improve family life removing some of the tensions that the family may face such as work and relationships. Marxist sociologists may argue that although family life can be fulfilling and happy the fact that contemporary British society is based on capitalism, which results in exploitation, family members will inevitably be placed under financial strain and tension which can cause problems of discontent and the breakdown of the family unit. Criticisms were that his theory was outdated and based on the ideology of the nuclear family alone. Marxist writers in the 1970s put forward a different perspective of the family they argued that the capitalist system exploits the free domestic labour of the housewife through the domestic division of labour. (Fulcher and Scott 2007). They argue that the concept of the nuclear family promotes the role of the man to be the breadwinner and the woman to be the housewife which has led women, if wanting to work, becoming the reserve army therefore being called upon when required, for example during times of war, according to Marxist theorists the nuclear family provides employers with cheap disposable labour that tends to be less valued than their male counterparts. (Fulcher and Scott 2007) On what foundation of the present family, the bourgeois family based? On capital, on private gain. In its completely developed form this family exists only among the bourgeoisie The bourgeois claptrap about the family and education, about the hallowed correlation of parent and child, becomes all the more disgusting, the more, by the action of modern industry, all family ties among the proletarians are torn asunder, and their children transformed into simple articles of commerce and instruments of labour. (Marx and Engels, 1848 as cited in Ferrante 2011) Although Marx and Engels seem to be criticising the family and suggesting that the family may be considered as a tool for capitalism they were in fact suggesting that the family should be improved and it was the traditional family types that approved of the exploitation of women and children. According to Marsh and Keating (2006), Engels believed that the family exploited women and children and the end of the exploitation within the family could only be achieved in a communist society. The development of the Marist perspective continued throughout the century and the views of Engles and Marx were applied to a modern capitalist society. Modern Marxists would argue against the functionalists who stress that the purpose of the family is to raise children. Marxists agree that the family has a job but that job is to reproduce the labour power that maintains a capitalist society. It is also suggested that the family is a control mechanism that exerts social control on parents. Living in a highly consumer orientated society, children are often in competition with their peers and parents are in competition with other parents to ensure that their children have the best technology and prospects, the pressure to remain in a competing capitalist society gives the parents little choice but to compete in the workplace and accept capitalism as a norm. The family is thus an integral part of what Marxists call commodity fetishism; it helps to fuel the creation of false needs, which in order to be satisfied, require people to work hard. Mobile phones, laptops, X-boxes; all these frivolous things need to be bought by someone and in western capitalist societies it is now increasingly young people who are an important market. And young people come from, of course, families. (Abbot 2010) Historical changes in society have led to changes in feminist perspectives creating several waves of feminism. Although there are several types of feminist views including Liberal, Socialist, Radical and Marxist they do all share a common belief that women experience a range of social, economic, political and personal difficulties in their lives but they dont all agree on the cause of these difficulties. In general feminists have discarded the Functionalist theories of the nuclear family and suggested that many parents have socialised their children to behave in a manner that is considered to be appropriate to their gender roles. Feminists argue that when children see their parents behaving in their appropriate gender role then the children naturally assume that they should behave in the same way. Females have been shown what is considered to be feminine or female, dependence, obedience, conformity and domesticity and males have been encouraged by parents to be dominant, competitive and independent. (Holburn and Steel 2012) The radical feminist perspective of the family agrees basic concept of the Marxist view suggesting that exploitation is a key aspect of the family, however where Marxists suggest that capitalism plays a key role for the exploitation of women the feminist approach suggests that the division of labour is due to genetic predispositions that women are seen as the carers and are more suitable to child rearing that their male counterparts who are seen as the providers. Feminists argue that in the division of labour is unequal and that the domestic role is unrewarded and undervalued. According to Sheeran (1993) as cited in Marsh and Keating (2007) Marxist and radical feminists argue that the family is both an ideological construct and a repressive, socially produced reality, which helps to perpetuate capitalism and / or patriarchy. Such criticisms are overtly anti family, and argue that women have been forced into taking responsibility for child care by that agent of the state, the patriarc hal family. Morgan (1975) as cited in Haralambos and Holborn (2008) suggests that both functionalist and Marxist approaches, both presuppose a traditional model of the nuclear family where there is a married couple with children, where the husband is the breadwinner and where the wife stays at home to deal with the housework. The Interactionist approach is seen to be quite different and works at a micro level rather than the macro level like the previous perspectives. Symbolic interactionism has been an important theoretical perspective in family studies since its early development in the 1920s and 1930s. Symbolic interaction theory describes the family as a unit of interacting personalities. LaRossa and Reitzes (1993) as cited in International Encyclopedia of Marriage and Family (2003). Interactionists suggest that families reinforce and rejuvenate their bonds through the use of rituals. Some social scientists believe that rituals like gathering together for a family meal or the ritual of marriage using symbols to reinforce the bonds this can be seen as a source of family strength and if families preserve rituals then children will become more emotionally equipped to face problems in the future. (Hughes and Kroehler 2011). Critics stress that symbolic interactionism only looks at the micro level and that this perspective does not take into account larger issues of society. The New Right perspective of the family was born from functionalist ideology and supports the theory that the nuclear family is the only type of family that works effectively within British society. Between the 1950s and the 1990s the nuclear family began to alter, families were no longer perceived to be seen in the traditional stereotypical sense, families were becoming more diverse partly due to changes in the law, abortions were legalised, homosexuality decriminalised and the introduction of legislation such as the Sex Discrimination Act and the Equal Pay Act was introduced. New types of families were emerging. Single parent families, reconstituted families, individuals that cohabitated and the formation of same sex relationships that may or may not have had children from previous relationships. The New Right believe that the lack of traditional family and values and diversity has corrupted society. Lone parents were blamed for wayward children suggesting that without a male and f emale parent residing within the family unit then children would not be able to function as contributing members of society. Critics of the New Right suggest that by suggesting that the nuclear family is the only family that works for the benefit of society it ignores the dark side of the family issues such as domestic abuse and by trying to impress that the nuclear family is the superior and morally correct route it creates a them and us situation which can lead to discrimination, persecution and ultimately suggests that other family types are not families at all.(Yorkshire 2011) According to the Office for National Statistics (2011) between 2001 and 2010 families by type have altered slightly to show that there has been a slight increase in the alternative family and a slight decrease in what is considered to be the nuclear family. As the Office of National Statistics now take into account Civil Partnerships as legitimate families the figures reflect a more accurate account of the makeup of the ever changing British family however the categories in which families are assigned do not represent a true picture of the family as it fails to differentiate between reconstituted and nuclear families, while the minority groups such as civil partnership couples and lone parents have been allocated a category of their own. According to Morgan (1994) as cited in Marsh and Keating (2006) We cannot speak of the family as if it were a static and changing thing. Rather it is better to use the word as signifying the character of a complex series of processes over timewe should speak of family processes, family living or family life courses. In this way we will come to recognise that family life is always subject to change and variation that change is at the very heart of family living As society changes with time it can be argued that the family will alter and perceptions of the family from influences such as the media and politics will change the ideology. Although the school of thought may differ depending on what perspective is applied it appears that the family plays an important role within British society, it is important to recognise that without understanding the family it makes it difficult to understand problems that may arise such as domestic violence and child abuse and how they are interpreted as private troubles or public issues.

Orson Welles The Magnificent Ambersons Essay examples -- Movies Films

â€Å"The biggest mistake we have made is to consider that films are primarily a form of entertainment. The film is the greatest medium since the invention of movable type for exchanging ideas and information, and it is no more at its best in light entertainment than literature is at its best in the light novel.† - Orson Welles Orson Welles was passionate about film. By the young age of 25, he had directed, produced, and starred in what is today considered by most to be the greatest movie ever made, Citizen Kane. About a year later, Welles began work on his next film project, The Magnificent Ambersons. Based on the novel of the same name by Booth Tarkington, The Magnificent Ambersons tells the story of a falling aristocratic family in a small midwestern town during the late 19h century. It depicts the sad, rapid industrial growth of the Midwest. Welles, who grew up in Kenosha, Wisconsin and later in Illinois, understood what life was like in this part of the country and the novel allowed him to delve into his roots and examine his personal past. Surviving many risks and crises, this film is still revered today, almost 60 years later, as yet another great work of art by Orson Welles. After finishing up Citizen Kane, Welles’ search for a second film to fulfill his contract with the Hollywood studio RKO radio pictures was a hard one. He first wanted to make The Pickwick Papers with W.C. Fields, but someone else was already under contract to make the film with another studio. He also considered trying Joseph Conrad’s Heart of Darkness but RKO considered the project too experimental, and he finally decided to write a script based on Booth Tarkington’s novel, which had won a Pulitzer Prize in 1919 (McBride 53). It had been film... ...ugh The Magnificent Ambersons had a poor track record at the box office, it was still admired by many. A July 20, 1942 Time Magazine review called it â€Å"a great motion picture, adult and demanding. Artistically it is a textbook of advanced cinema technique† (Variety Film Reviews). It was also nominated for several Academy Awards including Best Picture, Best Art Direction, Best Black and White Cinematography and Best Supporting Actress (Agnes Moorehead) (O’Neil). Moorehead won the New York Film Critics Award for her performance as Fanny Minafer (O’Neill). â€Å"Agnes Moorehead gave a brilliant and thoughtful portrayal in the somber and murky Orson Welles picture The Magnificent Ambersons† (Variety Film Reviews). There has been speculation that the film would be widely regarded as Welles's best work and possibly the greatest film ever made had an original cut been available.

Forest Application Vs. Agricultural Application Essay -- Nature Sludge

Forest Application Vs. Agricultural Application There is increasing interest in using forest systems for the treatment of wastewater sludge. Forest application offers several advantages over agricultural application. There is usually a long period of time between the application and removal of the crop. This gives an opportunity for organic compounds to decompose. Another advantage is that there is less of a chance that organic or inorganic compounds will enter the food chain after harvest. Trees benefit from sewage sludge through increased growth rates. In an oak forest in northern Michigan, sludge was applied at a rate of 8 Mg dry solids/ha to provide 400 kg/ha of nitrogen. Tree diameter growth was increased by 63% over areas that had no application (Nguyen et al. 1986). In loblolly pine stands in South Carolina, basal area growth was increased by 46% and tree volume by 33% by the application of sludge (McKee et al. 1986). Sludge increases the productivity of understory vegetation on poor-quality sites. Herbivorous animals benefit for the increased quantity and quality of vegetation(increased phosphorous and protein levels)(Haufler and West 1986). Sludge may be applied to all ages of forest, from clearcuts to mature forest. However, each growth stage has advantages and disadvantages. Clearcuts offer economical application, since temporary spray irrigation or solid spreaders may be used. The disadvantage is that applying high nutrient levels will increase weed growth and subsequent small mammal populations, making establishment of trees difficult. Application to young forests eliminates tree survival problems. However, overhead application is required due to small tree heights. This dictates that application be d... ...es. In Cole, D. W, C. L. Henry, and W. L. Nutter, eds. The Forest Alternative for Treatment and Utilization of Municipal and Industrial Wastes. University of Washington Press. Seattle, Washington. Nguyen, P. V., J. B. Hart,Jr., and D. M . Merkel. 1986. Municipal sludge fertilization on oak forests in Michigan: Short-term nutrient changes and growth responses. In Cole, D. W, C. L. Henry, and W. L. Nutter, eds. The Forest Alternative for Treatment and Utilization of Municipal and Industrial Wastes. University of Washington Press. Seattle, Washington. Red, J. T., and W. L. Nutter. 1986. Municipal wastewater renovation on a coastal plain, slash pine land treatment system. In Cole, D. W, C. L. Henry, and W. L. Nutter, eds. The Forest Alternative for Treatment and Utilization of Municipal and Industrial Wastes. University of Washington Press. Seattle, Washington.

Dangerous Animals of the Great Barrier Reef :: Ecology Nature Zoology Essays

Dangerous Animals of the Great Barrier Reef According to Dennis Fulkerson, one of the Australia Explorers (1996), the Great Barrier Reef is "God's underwater playground." Indeed, everyone in the group seemed to have a fabulous time exploring the reef. However, many of the group expressed some amount of fear about snorkelling on the reef, far away from the mainland. I began to wonder if there was really that much to be afraid of. We were only told that it was not box jellyfish season, and, more importantly, not to touch anything. According to Ryan (p 167), "In general, animals of the reef are benign; only a hungry shark or a mentally defective barracuda is likely to attack unprovoked." Nevertheless, there are a few creatures of which to be aware. Sea snakes, jellyfish, and certain varieties of sea urchins, coral, worms, starfish, mollusks, and fish possess defense and/or feeding mechanisms which can render them harmful if handled by humans. Bristle Worms Bristle worms possess numerous razor-sharp calcium carbonate bristles (setae) which the animal may raise if threatened. These bristles penetrate the skin easily and cause intense itching and sometimes infections. Bristles should be removed with forceps and a local anesthetic and ointment may be applied. The worm may also bite (Ryan, p 170). Sea Urchins Sea urchins, along with heart urchins and sand dollars, belong to the class Echinoidea, which is in the phylum Echinodermata. Echinoids possess numerous spines, which are used for locomotion and defense, and pedicellariae, tiny, pincer-like structures which are used in feeding. The spines, interestingly, consist of a single crystal of calcium carbonate "that would be as brittle as chalk if not for certain glycoproteins in it" (Harris, p 718). Some urchins have venomous spines which can cause severe pain. For example, according to Lutz (p 679), "Some sea urchins, especially those living on coral reefs, have hollow spines that contain a poison; the pacific Asthenoma has needle-sharp spines that can easily penetrate the skin, break off, and release a poison that is extremely painful and dangerous to humans." The flower urchin, Toxopneustes pileolus, (Figure 1) has poisonous pedicellariae which can potentially kill a human. Toxic material can also be contained in the layer of skin coveri ng the spines, so injection of a spine itself is enough to cause intense pain (Endean, p256). As for treatment, Ryan (p170) recommends removing all spines from affected area with forceps, as long as this can be accomplished without breaking the spine and thus releasing more of the poison.

Socratic Seminar Questions

English 1-2 1984 Socratic Seminar Questions 3. Reading and writing for pleasure promotes independent thought, but it is not dangerous. It lets you express how you are really feeling inside. It is something private that you decide whether or not someone may look at it. In the beginning of the book 1984, Winston writes in his notebook. He hesitated about it for a while before he actually began writing. He let out what was going through his mind, it was going really well but then he suddenly stopped writing. The thought that he could get caught terrified him. Big Brother considers writing and reading for pleasure to be dangerous.If people were to read and write they would realize what has been going on, and this would bring an end to Big Brother. 4. Revisionism still exists today, and we have been victims of it without us even knowing. When we were younger we would learn about Christopher Columbus and how he sailed on three ships and how he reached the Americas were he kindly greeted th e Native Americans. But is this really what happened? What they didn’t tell us was how Columbus committed genocide. He deliberately slaughtered so many of these indigenous people. Him and his crew raped, tortured, burned, and killed these Natives.We have been victims of revisionist history. I do agree that knowledge of history is powerful. If you are able to control history, you control the past. In 1984 Winston works in the Ministry of Truth were he changes the history to make it seem like Big Brother is always right. That is why the people had a blind fold over their eyes. They couldn’t realize what was really going because of the rewriting of history. 6. Thought crime, according to the book 1984 is thinking of anything that the Thought Police and the Party says is illegal. Illegal is anything that creates individuality. Individuality for the party is not good.I do believe a form of â€Å"thoughtcrime† exists in our society today. We have our own way of thinki ng that might not go along with what society or the government believes. The government has laws that many people do not agree with. But we really can’t do anything about it. We have our own thoughts that the government may not like, but the government can’t do anything about that either. 5. In the book 1984 technology helps the Party control Oceania. Today technology functions through television, radio, phones, cameras, satellites, and the internet. I believe it is used for evil. Yes, technology an be very helpful, but is it really needed? Back in time people didn’t have much technology and they were still happy. Technology now a day is used for evil things. Many people cyber bully. Because of cyber bullying many children have committed suicide. This is what technology has led to. Music is also a big part in technology that is very influential in technology. The music we hear daily have messages behind them. Most of the music is about sex, revenge, getting drun k, doing drugs, and many other things. This is what our brain is recording, these messaged are in our head. That is why I think technology can be evil.

Creative Writing Essay

Specific poetic forms have been developed by many cultures. In more developed, closed or â€Å"received† poetic forms, the rhyming scheme, meter and other elements of a poem are based on sets of rules, ranging from the relatively loose rules that govern the construction of an elegy to the highly formalized structure of the ghazal or villanelle. Described below are some common forms of poetry widely used across a number of languages. Additional forms of poetry may be found in the discussions of poetry of particular cultures or periods and in the glossary. Sonnet Among the most common forms of poetry through the ages is the sonnet, which by the 13th century was a poem of fourteen lines following a set rhyme scheme and logical structure. By the 14th century, the form further crystallized under the pen of Petrarch, whose sonnets were later translated in the 16th century by Sir Thomas Wyatt, who is credited with introducing the sonnet form into English literature. A sonnet’s first four lines typically introduce the topic. A sonnet usually follows an a-b-a-b rhyme pattern. The sonnet’s conventions have changed over its history, and so there are several different sonnet forms. Traditionally, in sonnets English poets use iambic pentameter, the Spenserian and Shakespearean sonnets being especially notable. In the Romance languages, the hendecasyllable and Alexandrine are the most widely used meters, though the Petrarchan sonnet has been used in Italy since the 14th century. Sonnets are particularly associated with love poetry, and often use a poetic diction heavily based on vivid imagery, but the twists and turns associated with the move from octave to sestet and to final couplet make them a useful and dynamic form for many subjects.] Shakespeare’s sonnets are among the most famous in English poetry, with 20 being included in the Oxford Book of English Verse. Shi (poetry) Shi (traditional Chinese: è © ©; simplified Chinese: è ¯â€"; pinyin: shÄ «; Wade-Giles: shih) Is the main type of Classical Chinese poetry.Within this form of poetry the most important variations are â€Å"folk song† styled verse (yuefu), â€Å"old style† verse (gushi), â€Å"modern style† verse (jintishi). In all cases, rhyming is obligatory. The Yuefu is a folk ballad or a poem written in the folk ballad style, and the number of lines and the length of the lines could be irregular. For the other variations of shi poetry, generally either a four line (quatrain, or jueju) or else an eight line poem is normal; either way with the even numbered lines rhyming. The line length is scanned by according number of characters (according to the convention that one character equals one syllable), and are predominantly either five or seven characters long, with a caesura before the final three syllables. The lines are generally end-stopped, considered as a series of couplets, and exhibit verbal parallelism as a key poetic device. ]The â€Å"old style† verse (gushi) is less formally strict than the jintishi, or regulated verse, which, despite the name â€Å"new style† verse actually had its theoretical basis laid as far back to Shen Yue, in the 5th or 6th century, although not considered to have reached its full development until the time of Chen Zi’ang (661-702) A good example of a poet known for his gushi poems is Li Bai. Among its other rules, the jintishi rules regulate the tonal variations within a poem, including the use of set patterns of the four tones of Middle Chinese The basic form of jintishi (lushi) has eight lines in four couplets, with parallelism between the lines in the second and third couplets. The couplets with parallel lines contain contrasting content but an identical grammatical relationship between words. Jintishi often have a rich poetic diction, full of allusion, and can have a wide range of subject, including history and politics. One of the masters of the form was Du Fu, who wrote during the Tang Dynasty (8th century). Villanelle The villanelle is a nineteen-line poem made up of five triplets with a closing quatrain; the poem is characterized by having two refrains, initially used in the first and third lines of the first stanza, and then alternately used at the close of each subsequent stanza until the final quatrain, which is concluded by the two refrains. The remaining lines of the poem have an a-b alternating rhyme.The villanelle has been used regularly in the English language since the late 19th century by such poets as Dylan Thomas, W. H. Auden,and Elizabeth Bishop. Tanka Tanka is a form of unrhymed Japanese poetry, with five sections totalling 31 onji (phonological units identical to morae), structured in a 5-7-5 7–7 pattern.There is generally a shift in tone and subject matter between the upper 5-7-5 phrase and the lower 7-7 phrase. Tanka were written as early as the Nara period by such poets as Kakinomoto no Hitomaro, at a time when Japan was emerging from a period where much of its poetry followed Chinese form. Tanka was originally the shorter form of Japanese formal poetry, and was used more heavily to explore personal rather than public themes. By the 13th century, tanka had become the dominant form of Japanese poetry, and it is still widely written today. Haiku Haiku is a popular form of unrhymed Japanese poetry, which evolved in the 17th century from the hokku, or opening verse of a renku. Generally written in a single vertical line, the haiku contains three sections totalling 17 onji, structured in a 5-7-5 pattern. Traditionally, haiku contain a kireji, or cutting word, usually placed at the end of one of the poem’s three sections, and a kigo, or season-word. The most famous exponent of the haiku was Matsuo BashÃ…  (1644–1694). An example of his writing: Ã¥ ¯Å'Ã¥ £ «Ã£  ®Ã© ¢ ¨Ã£â€šâ€žÃ¦â€°â€¡Ã£  «Ã£  ®Ã£ â€ºÃ£  ¦Ã¦ ±Å¸Ã¦Ë† ¸Ã¥Å"Ÿç” £ fuji no kaze ya oogi ni nosete Edo miyage the wind of Mt. Fuji I’ve brought on my fan! a gift from Edo Ode Odes were first developed by poets writing in ancient Greek, such as Pindar, and Latin, such as Horace. Forms of odes appear in many of the cultures that were influenced by the Greeks and Latins.The ode generally has three parts: a strophe, an antistrophe, and an epode. The antistrophes of the ode possess similar metrical structures and, depending on the tradition, similar rhyme structures. In contrast, the epode is written with a different scheme and structure. Odes have a formal poetic diction, and generally deal with a serious subject. The strophe and antistrophe look at the subject from different, often conflicting, perspectives, with the epode moving to a higher level to either view or resolve the underlying issues. Odes are often intended to be recited or sung by two choruses (or individuals), with the first reciting the strophe, the second the antistrophe, and both together the epode.Over time, differing forms for odes have developed with considerable variations in form and structure, but generally showing the original influence of the Pindaric or Horatian ode. One non-Western form which resembles the ode is the qasida in Persian poetry. Ghazal The ghazal (also ghazel, gazel, gazal, or gozol) is a form of poetry common in Arabic, Persian, Turkish, Azerbaijani, Urdu and Bengali poetry. In classic form, the ghazal has from five to fifteen rhyming couplets that share a refrain at the end of the second line. This refrain may be of one or several syllables, and is preceded by a rhyme. Each line has an identical meter. The ghazal often reflects on a theme of unattainable love or divinity. As with other forms with a long history in many languages, many variations have been developed, including forms with a quasi-musical poetic diction in Urdu. Ghazals have a classical affinity with Sufism, and a number of major Sufi religious works are written in ghazal form. The relatively steady meter and the use of the refrain produce an incantatory effect, which complements Sufi mystical themes well. Among the masters of the form is Rumi, a 13th-century Persian poet who lived in Konya, in present-day Turkey. Genres In addition to specific forms of poems, poetry is often thought of in terms of different genres and subgenres. A poetic genre is generally a tradition or classification of poetry based on the subject matter, style, or other broader literary characteristics. Some commentators view genres as natural forms of literature. Others view the study of genres as the study of how different works relate and refer to other works. Narrative poetry Narrative poetry is a genre of poetry that tells a story. Broadly it subsumes epic poetry, but the term â€Å"narrative poetry† is often reserved for smaller works, generally with more appeal to human interest. Narrative poetry may be the oldest type of poetry. Many scholars of Homer have concluded that his Iliad and Odyssey were composed from compilations of shorter narrative poems that related individual episodes. Much narrative poetry—such as Scottish and English ballads, and Baltic and Slavic heroic poems—is performance poetry with roots in a preliterate oral tradition. It has been speculated that some features that distinguish poetry from prose, such as meter, alliteration and kennings, once served as memory aids for bards who recited traditional tales. Notable narrative poets have included Ovid, Dante, Juan Ruiz, Chaucer, William Langland, Luà ­s de Camà µes, Shakespeare, Alexander Pope, Robert Burns, Fernando de Rojas, Adam Mickiewicz, Alexander Pushkin, Edgar Allan Poe and Alfred Tennyson. Epic poetry Epic poetry is a genre of poetry, and a major form of narrative literature. This genre is often defined as lengthy poems concerning events of a heroic or important nature to the culture of the time. It recounts, in a continuous narrative, the life and works of a heroic or mythological person or group of persons.] Examples of epic poems are Homer’s Iliad and Odyssey, Virgil’s Aeneid, the Nibelungenlied, Luà ­s de Camà µes’ Os Lusà ­adas, the Cantar de Mio Cid, the Epic of Gilgamesh, the Mahabharata, Valmiki’s Ramayana, Ferdowsi’s Shahnama, Nizami (or Nezami)’s Khamse (Five Books), and the Epic of King Gesar. While the composition of epic poetry, and of long poems generally, became less common in the west after the early 20th century, some notable epics have continued to be written. Derek Walcott won a Nobel prize to a great extent on the basis of his epic, Omeros. Verse drama and dramatic verse, Theatre of ancient Greece, Sanskrit drama, Chinese Opera, and Noh Dramatic poetry is drama written in verse to be spoken or sung, and appears in varying, sometimes related forms in many cultures. Greek tragedy in verse dates to the 6th century B.C., and may have been an influence on the development of Sanskrit drama, just as Indian drama in turn appears to have influenced the development of the bianwen verse dramas in China, forerunners of Chinese Opera.East Asian verse dramas also include Japanese Noh. Examples of dramatic poetry in Persian literature include Nizami’s two famous dramatic works, Layla and Majnun and Khosrow and Shirin, Ferdowsi’s tragedies such as Rostam and Sohrab, Rumi’s Masnavi, Gorgani’s tragedy of Vis and Ramin, and Vahshi’s tragedy of Farhad. Satirical Poetry Poetry can be a powerful vehicle for satire. The Romans had a strong tradition of satirical poetry, often written for political purposes. A notable example is the Roman poet Juvenal’s satires.[128] The same is true of the English satirical tradition. John Dryden (a Tory), the first Poet Laureate, produced in 1682 Mac Flecknoe, subtitled â€Å"A Satire on the True Blue Protestant Poet, T.S.† (a reference to Thomas Shadwell).Another master of 17th-century English satirical poetry was John Wilmot, 2nd Earl of Rochester.Satirical poets outside England include Poland’s Ignacy Krasicki, Azerbaijan’s Sabir and Portugal’s Manuel Maria Barbosa du Bocage. Lyric poetry Lyric poetry is a genre that, unlike epic and dramatic poetry, does not attempt to tell a story but instead is of a more personal nature. Poems in this genre tend to be shorter, melodic, and contemplative. Rather than depicting characters and actions, it portrays the poet’s own feelings, states of mind, and perceptions.Notable poets in this genre include John Donne, Gerard Manley Hopkins, and Antonio Machado. Elegy An elegy is a mournful, melancholy or plaintive poem, especially a lament for the dead or a funeral song. The term â€Å"elegy,† which originally denoted a type of poetic meter (elegiac meter), commonly describes a poem of mourning. An elegy may also reflect something that seems to the author to be strange or mysterious. The elegy, as a reflection on a death, on a sorrow more generally, or on something mysterious, may be classified as a form of lyric poetry. Notable practitioners of elegiac poetry have included Propertius, Jorge Manrique, Jan Kochanowski, Chidiock Tichborne, Edmund Spenser, Ben Jonson, John Milton, Thomas Gray, Charlotte Turner Smith, William Cullen Bryant, Percy Bysshe Shelley, Johann Wolfgang von Goethe, Evgeny Baratynsky, Alfred Tennyson, Walt Whitman, Louis Gallet, Antonio Machado, Juan Ramà ³n Jimà ©nez, William Butler Yeats, Rainer Maria Rilke, and Virginia Woolf. Fable The fable is an ancient literary genre, often (though not invariably) set in verse. It is a succinct story that features anthropomorphized animals, plants, inanimate objects, or forces of nature that illustrate a moral lesson (a â€Å"moral†). Verse fables have used a variety of meter and rhyme patterns. Notable verse fabulists have included Aesop, Vishnu Sarma, Phaedrus, Marie de France, Robert Henryson, Biernat of Lublin, Jean de La Fontaine, Ignacy Krasicki, Fà ©lix Marà ­a de Samaniego, Tomà ¡s de Iriarte, Ivan Krylov and Ambrose Bierce. Prose poetry Prose poetry is a hybrid genre that shows attributes of both prose and poetry. It may be indistinguishable from the micro-story (a.k.a. the â€Å"short short story†, â€Å"flash fiction†). While some examples of earlier prose strike modern readers as poetic, prose poetry is commonly regarded as having originated in 19th-century France, where its practitioners included Aloysius Bertrand, Charles Baudelaire, Arthur Rimbaud and Stà ©phane Mallarmà ©.Since the late 1980s especially, prose poetry has gained increasing popularity, with entire journals, such as The Prose Poem: An International Journal,Contemporary Haibun Onlinedevoted to that genre. Speculative poetry Speculative poetry, also known as fantastic poetry, (of which weird or macabre poetry is a major subclassification), is a poetic genre which deals thematically with subjects which are ‘beyond reality’, whether via extrapolation as in science fiction or via weird and horrific themes as in horror fiction. Such poetry appears regularly in modern science fiction and horror fiction magazines. Edgar Allan Poe is sometimes seen as the â€Å"father of speculative poetry†.

Synchronous Motor

Chapter (11) Synchronous Motors Introduction It may be recalled that a d. c. generator can be run as a d. c. motor. In like manner, an alternator may operate as a motor by connecting its armature winding to a 3-phase supply. It is then called a synchronous motor. As the name implies, a synchronous motor runs at synchronous speed (Ns = 120f/P) i. e. , in synchronism with the revolving field produced by the 3-phase supply. The speed of rotation is, therefore, tied to the frequency of the source.Since the frequency is fixed, the motor speed stays constant irrespective of the load or voltage of 3phase supply. However, synchronous motors are not used so much because they run at constant speed (i. e. , synchronous speed) but because they possess other unique electrical properties. In this chapter, we shall discuss the working and characteristics of synchronous motors. 11. 1 Construction A synchronous motor is a machine that operates at synchronous speed and converts electrical energy into mechanical energy. It is fundamentally an alternator operated as a motor.Like an alternator, a synchronous motor has the following two parts: (i) a stator which houses 3-phase armature winding in the slots of the stator core and receives power from a 3-phase supply [See (Fig. (11. 1)]. (ii) a rotor that has a set of salient poles excited by direct current to form alternate N and S poles. The exciting coils are connected in series to two slip rings and direct current is fed into the winding from an external exciter mounted on the rotor shaft. The stator is wound for the same number of poles as the rotor poles.As in the case of an induction motor, the number of poles determines the synchronous speed of the motor: Fig. (11. 1) 293 Synchronous speed, N s = where 120f P f = frequency of supply in Hz P = number of poles An important drawback of a synchronous motor is that it is not self-starting and auxiliary means have to be used for starting it. 11. 2 Some Facts about Synchronous Motor Some salient features of a synchronous motor are: (i) A synchronous motor runs at synchronous speed or not at all. Its speed is constant (synchronous speed) at all loads. The only way to change its speed is to alter the supply frequency (Ns = 120 f/P). ii) The outstanding characteristic of a synchronous motor is that it can be made to operate over a wide range of power factors (lagging, unity or leading) by adjustment of its field excitation. Therefore, a synchronous motor can be made to carry the mechanical load at constant speed and at the same time improve the power factor of the system. (iii) Synchronous motors are generally of the salient pole type. (iv) A synchronous motor is not self-starting and an auxiliary means has to be used for starting it. We use either induction motor principle or a separate starting motor for this purpose.If the latter method is used, the machine must be run up to synchronous speed and synchronized as an alternator. 11. 3 Operating Principle The fact that a synchronous motor has no starting torque can be easily explained. (i) Consider a 3-phase synchronous motor having two rotor poles NR and SR. Then the stator will also be wound for two poles NS and SS. The motor has direct voltage applied to the rotor winding and a 3-phase voltage applied to the stator winding. The stator winding produces a rotating field which revolves round the stator at synchronous speed Ns(= 120 f/P).The direct (or zero frequency) current sets up a two-pole field which is stationary so long as the rotor is not turning. Thus, we have a situation in which there exists a pair of revolving armature poles (i. e. , NS ? SS) and a pair of stationary rotor poles (i. e. , NR ? SR). (ii) Suppose at any instant, the stator poles are at positions A and B as shown in Fig. (11. 2 (i)). It is clear that poles NS and NR repel each other and so do the poles SS and SR. Therefore, the rotor tends to move in the anticlockwise direction. After a period of half-cycle (or ? = 1 /100 second), the polarities of the stator poles are reversed but the polarities of the rotor poles remain the same as shown in Fig. (11. 2 (ii)). Now SS and NR attract 294 each other and so do NS and SR. Therefore, the rotor tends to move in the clockwise direction. Since the stator poles change their polarities rapidly, they tend to pull the rotor first in one direction and then after a period of half-cycle in the other. Due to high inertia of the rotor, the motor fails to start. Fig. (10. 2) Hence, a synchronous motor has no self-starting torque i. e. , a synchronous motor cannot start by itself.How to get continuous unidirectional torque? If the rotor poles are rotated by some external means at such a speed that they interchange their positions along with the stator poles, then the rotor will experience a continuous unidirectional torque. This can be understood from the following discussion: (i) Suppose the stator field is rotating in the clockwise direction and the rotor is als o rotated clockwise by some external means at such a speed that the rotor poles interchange their positions along with the stator poles. (ii) Suppose at any instant the stator and rotor poles are in the position shown in Fig. 11. 3 (i)). It is clear that torque on the rotor will be clockwise. After a period of half-cycle, the stator poles reverse their polarities and at the same time rotor poles also interchange their positions as shown in Fig. (11. 3 (ii)). The result is that again the torque on the rotor is clockwise. Hence a continuous unidirectional torque acts on the rotor and moves it in the clockwise direction. Under this condition, poles on the rotor always face poles of opposite polarity on the stator and a strong magnetic attraction is set up between them.This mutual attraction locks the rotor and stator together and the rotor is virtually pulled into step with the speed of revolving flux (i. e. , synchronous speed). (iii) If now the external prime mover driving the rotor is removed, the rotor will continue to rotate at synchronous speed in the clockwise direction because the rotor poles are magnetically locked up with the stator poles. It is due to 295 this magnetic interlocking between stator and rotor poles that a synchronous motor runs at the speed of revolving flux i. e. , synchronous speed. Fig. (11. 3) 11. Making Synchronous Motor Self-Starting A synchronous motor cannot start by itself. In order to make the motor self-starting, a squirrel cage winding (also called damper winding) is provided on the rotor. The damper winding consists of copper bars embedded in the pole faces of the salient poles of the rotor as shown in Fig. (11. 4). The bars are short-circuited at the ends to form in effect a partial Fig. (11. 4) squirrel cage winding. The damper winding serves to start the motor. (i) To start with, 3-phase supply is given to the stator winding while the rotor field winding is left unenergized.The rotating stator field induces currents in the damper or squirrel cage winding and the motor starts as an induction motor. (ii) As the motor approaches the synchronous speed, the rotor is excited with direct current. Now the resulting poles on the rotor face poles of opposite polarity on the stator and a strong magnetic attraction is set up between them. The rotor poles lock in with the poles of rotating flux. Consequently, the rotor revolves at the same speed as the stator field i. e. , at synchronous speed. iii) Because the bars of squirrel cage portion of the rotor now rotate at the same speed as the rotating stator field, these bars do not cut any flux and, therefore, have no induced currents in them. Hence squirrel cage portion of the rotor is, in effect, removed from the operation of the motor. 296 It may be emphasized here that due to magnetic interlocking between the stator and rotor poles, a synchronous motor can only run at synchronous speed. At any other speed, this magnetic interlocking (i. e. , rotor poles facing o pposite polarity stator poles) ceases and the average torque becomes zero.Consequently, the motor comes to a halt with a severe disturbance on the line. Note: It is important to excite the rotor with direct current at the right moment. For example, if the d. c. excitation is applied when N-pole of the stator faces Npole of the rotor, the resulting magnetic repulsion will produce a violent mechanical shock. The motor will immediately slow down and the circuit breakers will trip. In practice, starters for synchronous motors arc designed to detect the precise moment when excitation should be applied. 11. 5 Equivalent Circuit Unlike the induction motor, the synchronous motor is connected to two electrical systems; a d. . source at the rotor terminals and an a. c. system at the stator terminals. 1. Under normal conditions of synchronous motor operation, no voltage is induced in the rotor by the stator field because the rotor winding is rotating at the same speed as the stator field. Only the impressed direct current is present in the rotor winding and ohmic resistance of this winding is the only opposition to it as shown in Fig. (11. 5 (i)). 2. In the stator winding, two effects are to be considered, the effect of stator field on the stator winding and the effect of the rotor field cutting the stator conductors at synchronous speed.Fig. (11. 5) (i) The effect of stator field on the stator (or armature) conductors is accounted for by including an inductive reactance in the armature winding. This is called synchronous reactance Xs. A resistance Ra must be considered to be in series with this reactance to account for the copper losses in the stator or armature winding as shown in Fig. (11. 5 (i)). This 297 resistance combines with synchronous reactance and gives the synchronous impedance of the machine. (ii) The second effect is that a voltage is generated in the stator winding by the synchronously-revolving field of the rotor as shown in Fig. 11. 5 (i)). This generat ed e. m. f. EB is known as back e. m. f. and opposes the stator voltage V. The magnitude of Eb depends upon rotor speed and rotor flux ? per pole. Since rotor speed is constant; the value of Eb depends upon the rotor flux per pole i. e. exciting rotor current If. Fig. (11. 5 (i)) shows the schematic diagram for one phase of a star-connected synchronous motor while Fig. (11. 5 (ii)) shows its equivalent circuit. Referring to the equivalent circuit in Fig. (11. 5 (ii)). Net voltage/phase in stator winding is Er = V ? Eb Armature current/phase, I a = where 2 Zs = R 2 + X s a hasor difference Er Zs This equivalent circuit helps considerably in understanding the operation of a synchronous motor. A synchronous motor is said to be normally excited if the field excitation is such that Eb = V. If the field excitation is such that Eb < V, the motor is said to be under-excited. The motor is said to be over-excited if the field excitation is such that Eb > V. As we shall see, for both normal an d under excitation, the motor has lagging power factor. However, for over-excitation, the motor has leading power factor.Note: In a synchronous motor, the value of Xs is 10 to 100 times greater than Ra. Consequently, we can neglect Ra unless we are interested in efficiency or heating effects. 11. 6 Motor on Load In d. c. motors and induction motors, an addition of load causes the motor speed to decrease. The decrease in speed reduces the counter e. m. f. enough so that additional current is drawn from the source to carry the increased load at a reduced speed. This action cannot take place in a synchronous motor because it runs at a constant speed (i. e. , synchronous speed) at all loads.What happens when we apply mechanical load to a synchronous motor? The rotor poles fall slightly behind the stator poles while continuing to run at 298 synchronous speed. The angular displacement between stator and rotor poles (called torque angle ? ) causes the phase of back e. m. f. Eb to change w. r. t. supply voltage V. This increases the net e. m. f. Er in the stator winding. Consequently, stator current Ia ( = Er/Zs) increases to carry the load. Fig. (11. 6) The following points may be noted in synchronous motor operation: (i) A synchronous motor runs at synchronous speed at all loads.It meets the increased load not by a decrease in speed but by the relative shift between stator and rotor poles i. e. , by the adjustment of torque angle ?. (ii) If the load on the motor increases, the torque angle a also increases (i. e. , rotor poles lag behind the stator poles by a greater angle) but the motor continues to run at synchronous speed. The increase in torque angle ? causes a greater phase shift of back e. m. f. Eb w. r. t. supply voltage V. This increases the net voltage Er in the stator winding. Consequently, armature current Ia (= Er/Zs) increases to meet the load demand. iii) If the load on the motor decreases, the torque angle ? also decreases. This causes a smaller phase shift of Eb w. r. t. V. Consequently, the net voltage Er in the stator winding decreases and so does the armature current Ia (= Er/Zs). 11. 7 Pull-Out Torque There is a limit to the mechanical load that can be applied to a synchronous motor. As the load increases, the torque angle ? also increases so that a stage is reached when the rotor is pulled out of synchronism and the motor comes to a standstill. This load torque at which the motor pulls out of synchronism is called pull—out or breakdown torque.Its value varies from 1. 5 to 3. 5 times the full— load torque. When a synchronous motor pulls out of synchronism, there is a major disturbance on the line and the circuit breakers immediately trip. This protects the motor because both squirrel cage and stator winding heat up rapidly when the machine ceases to run at synchronous speed. 299 11. 8 Motor Phasor Diagram Consider an under-excited ^tar-connected synchronous motor (Eb < V) supplied with fixed excitation i. e. , back e. m. f. Eb is constantLet V = supply voltage/phase Eb = back e. m. f. /phase Zs = synchronous impedance/phase (i) Motor on no loadWhen the motor is on no load, the torque angle ? is small as shown in Fig. (11. 7 (i)). Consequently, back e. m. f. Eb lags behind the supply voltage V by a small angle ? as shown in the phasor diagram in Fig. (11. 7 (iii)). The net voltage/phase in the stator winding, is Er. Armature current/phase, Ia = Er/Zs The armature current Ia lags behind Er by ? = tan-1 Xs/Ra. Since Xs >> Ra, Ia lags Er by nearly 90Â °. The phase angle between V and Ia is ? so that motor power factor is cos ?. Input power/phase = V Ia cos ? Fig. (11. 7) Thus at no load, the motor takes a small power VIa cos ? phase from the supply to meet the no-load losses while it continues to run at synchronous speed. (ii) Motor on load When load is applied to the motor, the torque angle a increases as shown in Fig. (11. 8 (i)). This causes Eb (its magnitude is constant as excitation is fixed) to lag behind V by a greater angle as shown in the phasor diagram in Fig. (11. 8 (ii)). The net voltage/phase Er in the stator winding increases. Consequently, the motor draws more armature current Ia (=Er/Zs) to meet the applied load. Again Ia lags Er by about 90Â ° since Xs >> Ra. The power factor of the motor is cos ?. 300 Input power/phase, Pi = V Ia cos ?Mechanical power developed by motor/phase Pm = Eb ? Ia ? cosine of angle between Eb and Ia = Eb Ia cos(? ? ? ) Fig. (11. 8) 11. 9 Effect of Changing Field Excitation at Constant Load In a d. c. motor, the armature current Ia is determined by dividing the difference between V and Eb by the armature resistance Ra. Similarly, in a synchronous motor, the stator current (Ia) is determined by dividing voltage-phasor resultant (Er) between V and Eb by the synchronous impedance Zs. One of the most important features of a synchronous motor is that by changing the field excitation, it can be made to operate from lagging to eadin g power factor. Consider a synchronous motor having a fixed supply voltage and driving a constant mechanical load. Since the mechanical load as well as the speed is constant, the power input to the motor (=3 VIa cos ? ) is also constant. This means that the in-phase component Ia cos ? drawn from the supply will remain constant. If the field excitation is changed, back e. m. f Eb also changes. This results in the change of phase position of Ia w. r. t. V and hence the power factor cos ? of the motor changes. Fig. (11. 9) shows the phasor diagram of the synchronous motor for different values of field excitation.Note that extremities of current phasor Ia lie on the straight line AB. (i) Under excitation The motor is said to be under-excited if the field excitation is such that Eb < V. Under such conditions, the current Ia lags behind V so that motor power factor is lagging as shown in Fig. (11. 9 (i)). This can be easily explained. Since Eb < V, the net voltage Er is decreased and turn s clockwise. As angle ? (= 90Â °) between Er and Ia is constant, therefore, phasor Ia also turns clockwise i. e. , current Ia lags behind the supply voltage. Consequently, the motor has a lagging power factor. 301 ii) Normal excitation The motor is said to be normally excited if the field excitation is such that Eb = V. This is shown in Fig. (11. 9 (ii)). Note that the effect of increasing excitation (i. e. , increasing Eb) is to turn the phasor Er and hence Ia in the anti-clockwise direction i. e. , Ia phasor has come closer to phasor V. Therefore, p. f. increases though still lagging. Since input power (=3 V Ia cos ? ) is unchanged, the stator current Ia must decrease with increase in p. f. Fig. (11. 9) Suppose the field excitation is increased until the current Ia is in phase with the applied voltage V, making the p. . of the synchronous motor unity [See Fig. (11. 9 (iii))]. For a given load, at unity p. f. the resultant Er and, therefore, Ia are minimum. (iii) Over excitation T he motor is said to be overexcited if the field excitation is such that Eb > V. Under-such conditions, current Ia leads V and the motor power factor is leading as shown in Fig. (11. 9 (iv)). Note that Er and hence Ia further turn anti-clockwise from the normal excitation position. Consequently, Ia leads V. From the above discussion, it is concluded that if the synchronous motor is under-excited, it has a lagging power factor.As the excitation is increased, the power factor improves till it becomes unity at normal excitation. Under such conditions, the current drawn from the supply is minimum. If the excitation is further increased (i. e. , over excitation), the motor power factor becomes leading. Note. The armature current (Ia) is minimum at unity p. f and increases as the power factor becomes poor, either leading or lagging. 302 11. 10 Phasor Diagrams With Different Excitations Fig. (11. 10) shows the phasor diagrams for different field excitations at constant load. Fig. (11. 10 (i )) shows the phasor diagram for normal excitation (Eb = V), whereas Fig. 11. 10 (ii)) shows the phasor diagram for under-excitation. In both cases, the motor has lagging power factor. Fig. (11. 10 (iii)) shows the phasor diagram when field excitation is adjusted for unity p. f. operation. Under this condition, the resultant voltage Er and, therefore, the stator current Ia are minimum. When the motor is overexcited, it has leading power factor as shown in Fig. (11. 10 (iv)). The following points may be remembered: (i) For a given load, the power factor is governed by the field excitation; a weak field produces the lagging armature current and a strong field produces a leading armature current. ii) The armature current (Ia) is minimum at unity p. f and increases as the p. f. becomes less either leading or lagging. Fig. (11. 10) 11. 11 Power Relations Consider an under-excited star-connected synchronous motor driving a mechanical load. Fig. (11. 11 (i)) shows the equivalent circuit for one phase, while Fig. (11. 11 (ii)) shows the phasor diagram. Fig. (11. 11) 303 (i) (ii) Input power/phase, Pi = V Ia cos ? Mechanical power developed by the motor/phase, Pm = Eb ? Ia ? cosine of angle between Eb and Ia = Eb Ia cos(? ? ? ) Armature Cu loss/phase = I 2 R a = Pi ? Pm a Output power/phasor, Pout = Pm ?Iron, friction and excitation loss. (iii) (iv) Fig. (11. 12) shows the power flow diagram of the synchronous motor. Fig. (11. 12) 11. 12 Motor Torque Gross torque, Tg = 9. 55 where Pm N-m Ns Pm = Gross motor output in watts = Eb Ia cos(? ? ? ) Ns = Synchronous speed in r. p. m. Shaft torque, Tsh = 9. 55 Pout N-m Ns It may be seen that torque is directly proportional to the mechanical power because rotor speed (i. e. , Ns) is fixed. 11. 13 Mechanical Power Developed By Motor (Armature resistance neglected) Fig. (11. 13) shows the phasor diagram of an under-excited synchronous motor driving a mechanical load.Since armature resistance Ra is assumed zero. tan? = Xs/Ra = ? an d hence ? = 90Â °. Input power/phase = V Ia cos ? Fig. (11. 13) 304 Since Ra is assumed zero, stator Cu loss (I 2 R a ) will be zero. Hence input power a is equal to the mechanical power Pm developed by the motor. Mech. power developed/ phase, Pm = V Ia cos ? Referring to the phasor diagram in Fig. (11. 13), (i) AB = E r cos ? = I a X s cos ? Also AB = E b sin ? ? E b sin ? = I a X s cos ? or I a cos ? = E b sin ? Xs Substituting the value of Ia cos ? in exp. (i) above, Pm = = V Eb Xs VEb Xs per phase for 3-phaseIt is clear from the above relation that mechanical power increases with torque angle (in electrical degrees) and its maximum value is reached when ? = 90Â ° (electrical). Pmax = V Eb Xs per phase Under this condition, the poles of the rotor will be mid-way between N and S poles of the stator. 11. 14 Power Factor of Synchronous Motors In an induction motor, only one winding (i. e. , stator winding) produces the necessary flux in the machine. The stator winding must draw re active power from the supply to set up the flux. Consequently, induction motor must operate at lagging power factor.But in a synchronous motor, there are two possible sources of excitation; alternating current in the stator or direct current in the rotor. The required flux may be produced either by stator or rotor or both. (i) If the rotor exciting current is of such magnitude that it produces all the required flux, then no magnetizing current or reactive power is needed in the stator. As a result, the motor will operate at unity power factor. 305 (ii) If the rotor exciting current is less (i. e. , motor is under-excited), the deficit in flux is made up by the stator. Consequently, the motor draws reactive power to provide for the remaining flux.Hence motor will operate at a lagging power factor. (iii) If the rotor exciting current is greater (i. e. , motor is over-excited), the excess flux must be counterbalanced in the stator. Now the stator, instead of absorbing reactive power, a ctually delivers reactive power to the 3-phase line. The motor then behaves like a source of reactive power, as if it were a capacitor. In other words, the motor operates at a leading power factor. To sum up, a synchronous motor absorbs reactive power when it is underexcited and delivers reactive power to source when it is over-excited. 11. 15 Synchronous CondenserA synchronous motor takes a leading current when over-excited and, therefore, behaves as a capacitor. An over-excited synchronous motor running on no-load in known as synchronous condenser. When such a machine is connected in parallel with induction motors or other devices that operate at low lagging power factor, the leading kVAR supplied by the synchronous condenser partly neutralizes the lagging reactive kVAR of the loads. Consequently, the power factor of the system is improved. Fig. (11. 14) shows the power factor improvement by synchronous condenser method. The 3 ? ? load takes current IL at low lagging power factor cos ?L. The synchronous condenser takes a current Im which leads the voltage by an angle ? m. The resultant current I is the vector sum of Im and IL and lags behind the voltage by an angle ?. It is clear that ? is less than ? L so that cos ? is greater than cos ? L. Thus the power factor is increased from cos ? L to cos ?. Synchronous condensers are generally used at major bulk supply substations for power factor improvement. Advantages (i) By varying the field excitation, the magnitude of current drawn by the motor can be changed by any amount. This helps in achieving stepless control of power factor. ii) The motor windings have high thermal stability to short circuit currents. (iii) The faults can be removed easily. 306 Fig. (11. 14) Disadvantages (i) (ii) (iii) (iv) There are considerable losses in the motor. The maintenance cost is high. It produces noise. Except in sizes above 500 RVA, the cost is greater than that of static capacitors of the same rating. (v) As a synchronous m otor has no self-starting torque, then-fore, an auxiliary equipment has to be provided for this purpose. 11. 16 Applications of Synchronous Motors (i) Synchronous motors are particularly attractive for low speeds (< 300 r. . m. ) because the power factor can always be adjusted to unity and efficiency is high. (ii) Overexcited synchronous motors can be used to improve the power factor of a plant while carrying their rated loads. (iii) They are used to improve the voltage regulation of transmission lines. (iv) High-power electronic converters generating very low frequencies enable us to run synchronous motors at ultra-low speeds. Thus huge motors in the 10 MW range drive crushers, rotary kilns and variable-speed ball mills. 307 11. 17 Comparison of Synchronous and Induction Motors S. Particular No. 1.Speed 2. 3. 4. Power factor Excitation Economy 3-phase Induction Motor Remains constant (i. e. , Ns) from Decreases with load. no-load to full-load. Can be made to operate from Operates a t lagging lagging to leading power factor. power factor. Requires d. c. excitation at the No excitation for the rotor. rotor. Economical fcr speeds below Economical for 300 r. p. m. speeds above 600 r. p. m. Self-starting No self-starting torque. Auxiliary means have to be provided for starting. Complicated Simple More less Synchronous Motor 5. Self-starting 6. 7. Construction Starting torque 308