Far from the Madding Crowd Essay Example for Free

Far from the Madding Crowd Essay As they are speaking to the well-educated and proper Bathsheeba, this is effectively emphasised. When Bathsheebas eyes first fall upon the dying flock, Hardy describes the sheep as being helpless, livid and afflicted animals. These strong words add to the gloom of the scene, and Hardys description of Bathsheebas sad, bursting heart also creates despair. The ailments of the flock are described vividly which makes the whole situation seem much more real: Many of them foamed at the mouth, their breathing quick and short, whilst the bodies of all were fearfully distended In Bathsheebas moment of bewilderment, the rustics explain in their characteristic fashion that the only man in the area that could save them was Gabriel Oak. Immediately she protests: How dare you name that man in my presence! This shows that even a day after their argument, Oak is still very fresh on her mind. She rejects the rustics idea of Oak and turns to Boldwood for help. This act avoids confrontation and also yet again promotes her authority, this time over her workers. However, she quickly learns from the rustic people that Boldwood does not know the cure and that he sent for Oak when his sheep had the same disorder. Bathsheeba shouts at the workers and tells them to find somebody to cure the flock. This shows that she is too proud and stubborn to send for Oak, and does not want to, as it would show a weakness of her character. Never will I send for him-never! she said firmly As she witnesses an ewe dying in front of her, she repeats the above but this time wringing her hands. This signifies that she is frustrated; frustrated at herself for being so stubborn and frustrated that the only man who can save her prime flock is the same man she has just fallen out with. Hardy goes on to explain that with Bathsheeba the No, I wont virtually means I think I must. We have seen this inconsistency in Bathsheebas personality in the previous chapter when she declined Oaks opinion of her conduct at first and then went on to request it. It is a similar circumstance. Bathsheeba is far too stubborn and proud for her own good as it too often makes her life more difficult. However her inconsistency is the sure sign that her quest for power is really a show and that she is a lot weaker and sensitive really, for here she gives in again. Laban Jump on the Bay mare, and ride across, and say he (Oak) must return instantly-that I say so Bathsheebas above statement shows how very conscious she is of looking weak. It is quite clear that she has had a change of heart and decides to do the right thing and get Oak, yet still she must speak in her authoritative manner, seemingly trying to cover up her sensitive, more weak decision. As Laban rides towards where Oak is staying, Hardy names the places and features he passes on the way and on the way back. This is how Hardy conveys more of the area, naming places adds to the reality of the situation, and the reader can feel more involved and stimulated by the events occurring. The list of places also adds length to the passage where Laban rides to get Oak, which in turn adds to the suspense of the situation. On Labans return Bathsheeba sees that Oak is not with him, and Labans face is described as tragic, a dramatic word, which makes the reader think the worst. Laban explains that Oak would not come unless Bathsheba asked in a civil and proper manner, which annoys Bathsheeba Oak knows this. As much as Bathsheeba tries to control Oak, it is clear that Oak is in control this time. Her real sensitive and feminine personality is shown as another sheep falls dead and Bathsheeba bursts into tears another indication that she is not really strong and infinitely stubborn. Bathsheeba admits to her need for control and cover-up stubborn attitude when she murmurs: O, it is a wicked cruelty to me-it is-it is! And he drives me to do what I wouldnt This refers to her having to talk to Oak, whom she has only just sacked, as if she was politely asking a favour, and it is this sign of weakness that she hates so much. Bathsheeba decides to write Oak a short note, and Hardy conveys that it is heartfelt by describing her sobs and bursts of crying whilst she writes it. At the bottom of the note, driven by the drama of the time she conveys her first open passionate feelings toward Oak: Do not desert me, Gabriel! It is now clear that Bathsheeba does have close feelings towards Oak and is appealing to him right from her heart. The reader is not familiar with this highly feminine and sensitive side to Bathsheeba, which, again, adds to the whole drama of the scene. Oak responds this time, which conveys how strongly her emotional note appealed to the man who is in love with her, and cannot bear the thought of deserting her. Bathsheebas feminine charm had worked and she knew it for Hardy clearly states: She knew from the look of his face which sentence of her note had brought him After all of her powerful signs of affection, Bathsheeba still cannot face ceasing her commanding tone. Her first words to Oak: O, Gabriel, how could you serve me so unkindly! The flock is again described as Oak sees it: as turgid, prostrate forms. Hardy uses such striking words to fuel the readers suspense. Oak then gets to work, and the method he uses to cure the sheep is described in clear detail, which makes it more realistic. Oak manages to save the flock: When the love-led man had ceased from his labours Bathsheeba came and looked him in the face This line is important because it shows that all the effort Oak had just put in to save over fifty sheep was all driven by his love for Bathsheeba. It also contrasts from the end of the previous chapter because they look at each other, instead of avoiding eye contact, which conveys the romance conjured up by the heroic actions of Oak for the woman he loves, and her realisation of this. The chapter ends with Bathsheeba asking Oak to return to the farm, which he agrees to, and the last line, again contrasting with the previous chapter, conveying how Bathsheeba really feels: And she smiled on him again. Interestingly, the two chapters I have looked at above convey a cycle of the relationship between the two main characters. Everything starts off amicably before a crescendo of cutting comments result in an argument and the sacking of Oak. However, the occurrence of the flocks disorder makes Bathsheeba realise that she regrets sacking him and that she did it out of anger. After Oak saves the flock Bathsheeba is very grateful and their relationship becomes friendly again. Bathsheeba, as you have seen, is a very strong character and throughout the extract tries hard to control Oak. However, the situation develops, she ends up sacking him and then depending on him. Having noticed this, I also realised that this happens again in the book. At the beginning she rejects him as a husband, but then it is the actions of Oak who put out a serious fire, which begins at her new farm. This can be linked to the above extract: Oak gets rejected and then depended on by Bathsheeba. Similarly the night that Bathsheeba and her husband, sergeant Troy, celebrate their marriage is the same night that Oak saves the Harvest from a freak storm. Once again, Bathsheeba has denied Oak, but it is he who she depends upon in the end. In a way the whole book is based on the cycle conveyed in this extract. Bathsheeba continually rejects Oak, first for Boldwood, then for Troy. Oaks continual work on the farm keep it going whilst Bathsheebas marriage fails, and she turns to Oak for comfort: depending on him. Oaks devotion finally pays off in the end though, when eventually he does marry his true love, Bathsheeba Everdene.

Classical Theories And Crime Prevention Criminology Essay

Classical Theories And Crime Prevention Criminology Essay Crime is one of the greatest challenges the world is experiencing today. Crime rates have continually shot up at the same time taking new dimensions. People faced by the challenges of accomplishing their responsibilities under various economies, environmental situations and mental psychology often end up in committing crime. The society in response to this has stipulated several lawful mechanisms to arrest the situation, punishment being the utmost resolved means. Punishing the criminals without identifying the root cause of the crime does not necessary solve the vice, more approach is directed towards establishment of the why question the individual ended in committing crime. Societies have therefore formulated various criminological theories intended to gauge crime and criminals in passing out sound judgments. Each theory is applied in accordance to its relevance to a particular case since different criminological theories base their arguments on a different societal set up and var ied environmental/social conditions. This paper examines the application of classical choice theories in crime prevention. Introduction Classical choice theory dates back the 18th century and probably forms the bases of other theories too. This school of thought find it context by basing an argument that people are at liberty in decision making and therefore will behave in a manner that best suits their desires (Ambroise, 2006). The theory attributes that crime can be curbed to greater extent if there is a mobilization in societies to avert from getting influenced by their desires and pleasures in taking an action course. Crime can be contained by ensuring that punishment outweighs the pleasures derived from the crime committed (Siegel, 2008). This concept therefore, is a framework that tries to understand the behavior of people, the reasons that drives them in committing crime and various approaches to prevent a person in making choices that leads to crime. This theory was first developed in the 18th century by European philosophers who were criticizing the corrupt and authoritative arbitrary nature of their legal system. The ideas about people and the criminal behavior in determining crime came up when these philosophers were changing the legal system thus referring it as choice theory. On the other hand classical theory is based on arguments that the law should not be discriminative and should be applied equally amongst all (Cullen Agnew, 2006). The other aspect of the classical and choices theory is ground to the fact that human beings have the capacity to control these choices. The fear to the confrontation of the consequences resulting from their behaviors governs their mode of conduct and therefore refrains from criminal activities. Human beings have the ability to analyze situations with regard to their positive outcomes and their potential negatives. If the risks involved in engaging in certain behavior are much less than the benefits, then an individual is likely to commit that crime(Siegel, 2004). According to the philosophers, people act in a rational manner and choose towards their actions that gives them the greatest pleasure and least pain. The concept is equally applicable to the individuals who are involved in criminal activity. The classical theory holds that Delinquent behavior is a rational choice made by a motivated offender who perceives the chances of gain outweighs any perceived punishment or loss (Siegel Senna, 2004, p. 61). It is therefore an individuals choice to commit a crime after considerations of the benefits and possible consequences outcome. The characteristics traits of the offender, nature of the offence, specific factors and situation may affect his/her decision to a point. Psychological state of an individual in relation to emotions, strain and other external pressures is thus considered a contributory factor towards an individual committing a crime (Verma, 2007, p. 2020). The theory advocates that an individual is encouraged to commit a crime on opportunity availability. The classical theory helps to understand demographics, victimization and lifestyle of a process whereby the offender and the victim come into contact with one another. Researchers have identified aspects like being unmarried, male, leading an active lifestyle and frequenting bars can raise the risk of crime committing (Verma, 2007, p. 2020). People can opt to use illegal means in acquiring what they want to achieve if the consequences are not severe compared to the benefits associated with the crime. The society has to ensure that punishments accorded to criminals are severe if it is to achieve tangible results in trying to discourage criminal activities (Adler, Mueller, Laufer, 2004, p. 59). In relation to this, penalties for committing criminal acts must be known to the public, the punishment handed down must be swift and certain (Cullen Agnew, 2006). In the early 1700s, the Europe legal system was in disarray. The laws were open to interpretation and vague where the judges were accorded with a lot of power which they misused in interpreting laws to suit their interests. A penalty for a particular crime varied depending on who was at the receiving end. Equality in law application did not apply: Some criminals could go unpunished for a crime committed while others received a life sentence for the same (Cullen Agnew 2006). It had become the order of the day for the societies in the upper class bribing the judges to go free for offences committed while the poor with no resources to bribe their way out received unconditional harsh punishments. Petty offences like theft resulted to stiff punishments amounting to torture, life imprisonment or murder (Cullen Agnew, 2006). These legal shortcomings fueled a new wave targeting radical reforms in the mid 18th century. In the year the year 1740, Fredric II of Prussia terminated torture to inmates and death sentence for burglary offences in the year 1743 (Ambroise, 2006), a move that was welcomed by many European philosophers. Hobbes, a philosopher believed that people naturally pursue their own interest and in the course harm one another. Further, he asserted that rational individuals give up some freedom to the state willingly so that laws could be established which placed limits in order to prevent this harm from occurring (Cullen Agnew, 2006): A philosophical thought that led changes to criminal justice. Many criminology experts have contributed towards development of the classical and choice theories to make stand relevant to the ever-growing challenges surrounding the field. Much debate has rested on the measure of punishment a particular offence should hold. The purpose of punishment is crime deterrence, not social revenge. Certainty and swiftness rather than severity in punishment best secures this goal (Clear Cole, 2003, p. 33). The level scale of punishment should correspond to the nature of crime, in a proportionate system. This is because criminals are rational in the sense that they calculate the benefits and costs a behavior before action before deciding the action. The notion of Beccarias proportionate punishment is based upon this assumption and indeed this forms the basis of our current criminal justice system (Verma, 2007, p. 202). Classical choice theory emphasizes on the utilization of the resources available to reduce possible crime occurrence by advocating direct solutions to the problem arising from crimes. The verdict applied to the offender is meant to discourage further engagement in similar or associated crimes. By upsetting the balance between the benefits vs. costs, crime occurrence is found to reduce (Campie, 2003). Classical and choice theory application to crime This theory finds application up to date. The current approach is more focused on crime prevention. Policy makers still develop more approaches particularly those that have grounds with evidence and are results based which includes: policing initiatives, gun control tactics, increased incarceration and youth substance abuse and violence reduction strategies (Schuck, 2005, pp. 448-49).The following are some examples where this theory finds application. In an article entitled Giving students what they need, internal and external motivation approaches in the classroom are examined. Â   Student motivation is one of the input most needed for success. Educators wish for their students to be motivated since motivated students perform better. Â   Failure to this, students will possibly do poor work or no work at all, learn little, and frequently show reckless or unruly behaviors. There are two types of motivation-external and internal. Â   External motivation, the proverbial carrot, and stick approach predominates not only in most classrooms but also in the world (Erwin, 2003, p. 20). Â   Nonetheless, this approach is not as successful as internal motivation since it encourages students to work hard only for rewards. The promised reward has to increase once a behavior is achieved. Students do not fight to excel for the right reasons. Â   Internal motivation is a wiser choice for educators to use with students since it helps to fulfill some of the students basic needs. Â   Choice theory by William Glasser explores internal motivation and its impact on relationships. Â   According to Choice Theory, five basic needs constitute the source of internal motivation and guide all behavior (Erwin, 2003, p. 21). Â   Â   Â   Survival is one of the basic needs that our students need to have met. Â   The importance of having the survival need fulfilled is that it allows individuals to feel a sense of order and security. Â   Educators can help fulfill this need in the classroom by developing structured and consistent classroom procedures, allowing students to have snacks and drinks, and creating rules that allow a safe and respected environment (Erwin, 2003, p. 21). Choice theories are among the fastest growing theories in social science today. Many sociologists and political scientists defend the claim that rational choice theory can provide the basis for a unified and comprehensive theory of social behavior. Rational choice theory is distinguished from other theories because it emphasise on the fact all actions are calculative and rational. All social action can be seen as rationally motivated, as instrumental action, however much of it may appear to be irrational or non-rational. Choice Theory would be most beneficial in the reduction or control of crime. According to the Choice Theory, law-violating behavior should be viewed as an event that occurs when an offender decides to risk violating the law after considering his or her own personal situation (need for money, personal values, learning experiences) and the subsequent consequences. Other factors a potential criminal would consider includes: how well a target is protected, how affluent the neighborhood is and how efficient the local police happen to be. Before choosing to commit a crime, the reasoning criminal evaluates the risk of apprehension, the seriousness of the expected punishment, the value of the criminal enterprise, and his or her immediate need for criminal gain (Erwin, 2003). The Choice Theory shift attention to deviant activity or the act of engaging in criminal. The issue becomes, what can be done to make the act of crime or deviance less attractive to an individual, and how can crime or deviant behavior be prevented? The theory claims that crime prevention or at least crime reduction may be achieved through policies that convince criminals to disengage from criminal activities, delay their actions, or avoid a particular target. Strategies that are relevant to this perspective includes: target hardening, deadbolts, self-defense skills, neighborhood and watching programs that are illegal (Siegel, 2008). The theory is among the least complicated explanations for any action and involves a simple cost-benefit analysis. A violent individual gains some benefit from either threatening violence or acting out violently. If he or she does not receive, or fear receiving, some significant punishment, then he or she is more likely to act on his or her drive to act out in a violent manner (Ferguson, 2009). Crime is seductive and opens the door of opportunity. People may rationally choose crime because it provides them with psychological and social benefits and can help them solve problems. Choice Theory roots are based on the classical school of criminology, by Ceasare Beccaria, who viewed that crime is rational and can be prevented by punishment that is swift, certain and severe enough to deter crime. This has lead to a more contemporary version of classical theory, based on intelligent thought processes and criminal decision-making; today this is referred to as the rational choice approach to crime causation (Siegel, 2007). This theoretical perspective suggests that: people have free will to choose criminal or conventional behaviors; people choose to commit crime for reasons of greed or personal need; and crime can be controlled only by the fear of criminal sanctions (Siegel, 2007). Offenders choose crime after considering both personal-money, revenge, thrills, entertainment-and situational factors, such as target availability, security measures and police presence (Siegel, 2007). The choice theorists view crime as offense- and offender-specific; and that a number of personal factors condition people to choose crime; and the decision to commit crime regardless of its substance, is structured by where it occurs and the circumstances revolving the offender and the environment (Siegel, 2007). New and tougher laws are now being put in place to bring the crime rate down. With this reflection, the U.S public policy of 1980 created a mandatory prison sentences for drug offenders. Surprisingly, the prisons population swelled up with minors constituting a considerable figure (Schmallager, 2006). Despite liberal anguish, conservative view of crime control shaped criminal justice for a lengthy period. Most Americans that were passionate opponents of abortion on the ground that it takes human life, became ironically ardent supporters of the death penalty (Siegel, 2008) The tough attitude measures was overwhelmingly supported owing the fact that while the prisons were getting overcrowded, crime was on the other hand was noted to be on the decline. These developments saw the classical theories take another advanced dimension. The newer approach is based on intelligent thought processes and criminal decision making. Experts in criminology ascertain that the choice theory is in a way different from the original classical theory which posed criminals as individuals who maximized their pleasure and minimized pain. These experts suggest that if individuals are caught while committing crime, it is because they are slow thinkers and are not perfect in their decision making. The causative factors influencing a crime are therefore extended to thought and emotion processes. Social relationship, environmental characteristics, individual traits and capabilities have also been found to impact criminals in decision making. Human behavior in making their choices is therefore willful and determined (Schmallager, 2006). The latest developments have described criminals as people who share profile and ambitions just as the normal citizens but have opted to use shortcuts in achieving their goals. They possess conventional citizens values strive for success, material attainment and work hard. Phillipe Bourgois in his study towards crack dealers in Harlem found that criminal lead a life where they were mobile, and struggling to make their ends meet: They only commit crime as a choice to use an illegal path in obtaining their goals that were deemed elusive using the legal way (Siegel, 2008). Crime has become attractive when an individual believes that its results is more beneficial compared to the cost. Their is a tendency for individuals engaging in a crime when they have a prior information that other who committed a similar crime made considerable achievements and are successful owing a crime previous committed. It is common that crime does not pay. Small but significant subsets of criminals earn as much as $50,000 yearly on crime. Such success is an encouraging factor to potential criminals. Offenders are however less likely to be inclined to committing crime if they perceive that their future earnings from criminal acts will be low and legal opportunities that can generate income are available. In this sense, rational choice is a function of a persons perceptions of conventional alternatives and opportunities (Siegel, 2008). The various authorities therefore have to keep tracking the employment level demands and creating more opportunities with considerable remunera tions. The job offers should be attractive so that it captures many individuals who would possibly engage in crime if there were no such offers. Criminals tend to adapt the rational choice of time and place of their crimes. Burglars for example prefer working between 9A.M and 11A.M and in the mid afternoon, when parents are either working or dropping off or picking their kids from school. They avoid Saturdays when most families are at home, and the morning hours of Sunday. Church hours are considered the best for weekend burglaries. Criminals are known to identify their targets hobbies so as to strike when the families are out for such outdoor hobbies. These activities are meant to create the least possible chances of being caught (Siegel, 2008). Family living in close neighborhoods can limits the access to their homes by disconnecting the subdivision from the adjacent ones and install walkways to locations safe to pedestrians, and to create bounds for them. Evidence of rational choice may also be found in the way criminals choose their targets locations. It has been noted that thieves avoid free standing buildings as there is likelihood of police surrounding them. They select targets that often do cash business like bars, supermarkets and restaurants. Burglars appear to monitor car and pedestrian traffic and avoid busy streets. Instead, they choose corner homes mostly those located near traffic lights, or those surrounded by wooded areas. Most burglars choose their neighborhood where they are conversant with the terrain and access roads. New location is only chosen when the target is worth and the law enforcers are not perceived to be very vigilant (Siegel, 2008). It is recommended that residents adopt the method of natural surveillance that advocates that: door is fully illuminated from outside and windows to be laced strategically for good visibility. If proper lighting system is placed along sidewalks and the entire yard in generals, thieves and burglars would lack the opportunity of striking in unnoticed. Commercial areas can be designed such a way that, check-out counters are located in front of the stores visible from the outside enabling the employees to view outside activities. Public entrances can be marked with a landscape, architecture and graphic to designate sidewalks, parking areas and design loading zones separately with designated delivery hours. Conclusion Classical choice theories concludes that the choice to engage in a criminal behavior is based on the offenders own interests. It is therefore in position to assert that most offenders act rationally and in their personal best interests. With this understanding of the decision making mechanism behind committing crime and in relation to criminal justice, professionals may be able to reduce crime level to a grater extent. This can only be achieved by making crime less attractive and the punishment more severe, swift to justice so that potential criminals get discouraged in engaging with the acts. Crime prevention can be used to propel the agencies responsible in enforcing city and county codes to help identify problem areas and properties that are crime risks or could become future crime risks. Factors that attract crime and violence like improper zoning, trash accumulation should be eliminated to reduce future victimization.

Gas turbine engine

Gas turbine engine TURBINE BLADE COOLING ABSTRACT INTRODUCTION It is well known from the thermodynamic analysis through literature survey that the performance of a gas turbine engine is strongly influenced by the temperature at the inlet to the turbine. Figure 1 illustrates the relation between the specific power output and turbine rotor inlet temperature. There is thus a growing tendency to use higher turbine inlet temperatures, implying increasing heat loads to the engine components. Engine manufacturers have recognised this for some time and have been continuously increasing turbine inlet temperature, especially during the last three decades. The blades are cooled by extracting air from the compressor stages. Modern gas turbine engines are designed to operate at inlet temperatures of 1800-2000K, which are far beyond the allowable metal temperatures. Thus, to maintain acceptable life and safety standards, the structural elements needs to be protected against the severe thermal environment. This calls for the design of an efficient cooling system for these elements. Rotor blade of high pressure gas turbine is such a critical element and hence the blade metal temperature should not be allowed to exceed beyond a value at which the life or safety standards cant be met. It is required to cool the blade in such a way that the amount of heat transferred from the externally flowing hot gas to the blade should be removed by an appropriate cooling design to limit the very high temperature. STRESSES IN THE BLADE Rotor blades of gas turbine are subjected to very high rotational speeds of the order of several thousand rpm and also are exposed to a variable thermal environment. Hence these blades are subjected to different types of stresses of different magnitudes and directions. As it is known, that the strength is a function of life and working temperature the net stress at any section of the blade should not exceed the maximum allowable value. The control on the blade metal temperature is the only way to sustain the stresses for the designed life of the blade for a specific operating condition and life requirement. Therefore to know about the cooling requirement, stresses should be predicted correctly on the blades at different sections. There are mainly four types of stresses with that rotor blades are being subjected; Centrifugal tensile stress Gas bending stress and Centrifugal bending stress Thermal stress 1.1. Centrifugal tensile stress Centrifugal stress in the rotor blade is due to the rotation of the blade. It is tensile in nature. This is the largest in magnitude but not necessarily the most important because it is almost a steady stress. When the rotational speed of the blade is specified, the allowable centrifugal tensile stress places a limit on the annulus area but does not affect the choice of blade chord. This stress is the basic cause of the blade failure due to the creep. 1.2. Centrifugal bending stress If the blade design is such that the centroids of all the blade cross-sections at different radii, taken perpendicular to the radial direction, do not lie in the same radial plane, centrifugal stresses arising in the blade will try to bend the blade. This type of stress arising due to the different directions of the centrifugal stresses in different blade sections is called as centrifugal bending stress. It will produce compressive stress in one side of the blade whereas tensile stress in the opposite side. Any torsional stress arising from these centrifugal stresses is small enough to be neglected. Thus this stress is very sensitive to manufacturing errors. 1.3. Gas bending stress The force arising from the change in angular momentum of the gas in the tangential direction, which produces the useful torque, also tries to bend the blade about the axis of rotation of the blades. The stress arising due to this bending force is called as gas bending stress. There may be change of momentum in the axial direction and in reaction turbines there will certainly be a pressure force in the axial direction. All these two will produce a bending moment in the blade about the tangential direction. The gas bending stress will be tensile in the leading and trailing edges and compressive in the back of the blade and with tapered twisted blades either the leading or trailing edge suffers with the maximum value of this stress. This is a fluctuating stress and its value becomes maximum when the rotor blade passes through the leading edge of the stator. 1.4. Gas bending stress Turbine blade is subjected to three-dimensional temperature gradients, along the blade height, along the blade profile and along the thickness of the blade. Due to these temperature gradients the blade fibres tend to deform unequally. This unequal deformation causes mainly two types of stresses to set up in the blade, compressive and tensile. As the blade considered is un-cooled therefore the contribution of the stress due to the temperature gradient along the thickness of the blade in net stress is not appreciable and can be neglected. Usually with the cooled blade this source of stress is main among all the sources of thermal stress. Again the thermal stress due to the temperature gradient along the blade height would not come in picture because the blade is free to expand along the height. Only the stress due to temperature gradient along the chord of the blade will contribute in net blade stress but its magnitude would not be much because the temperature gradient along the chord is not so high. BLADE MATERIAL AND STRENGTH Gas turbine blades are exposed to a very severe thermal atmosphere. The temperature is so high that it is fairly much more than the melting points of the common high-strength materials. Besides high temperature the requirement of durability is also another factor, which makes common materials unsuitable for use. Only super alloys may be suitable for this purpose. But the current trend of continuously increasing the turbine entry temperature attracted the concentration of the designers not only towards the new materials with well-improved mechanical and thermal properties but also to restrict the temperature of the blade material by its proper cooling. So, the material should have sufficient strength to face the operating situations. 1.5. Strength of blade material In ordinary temperature conditions the strength of the material under constant loads is estimated by tensile strength or yield strength. At high temperatures under action of constant loads in ordinary structural materials there appears the phenomenon of creep. It occurs as a result of prolonged exposure of materials to high stresses at high temperatures. This is particularly a acute problem on highly stressed rotating turbine blades and it occurs in the form of slowly and continuously developing plastic deformation. And excess of this plastic deformation causes the failure of the component. It is observed that at constant stress the higher the temperature the more quickly proceeds the process of creep i.e. the lesser the life of the component. It means that at a particular stress lesser will be the temperature higher will be the life of component. Therefore life of the component is a function of working temperature and stress. Hence to maintain the life of the component at a desire v alue it is required to lower the temperature of the component. Gas turbines operate in conditions of high temperatures and therefore in highly stressed components like rotor blades there appears the phenomenon of creep. Therefore for these cases where creep is the main criterion behind component failure the ultimate tensile stress is defined as the stress at which the component fails at a certain working temperature after the expiry of a certain period of time. It means that the strength of the material subjected at high temperatures is a function of this temperature and its operational life. PAST COOLING The technology of turbine cooling was recognised by some almost from the inception of the first turbojet engine. Cooling studies were first performed in the 1940 and many investigations were carried on in the 1950s. Around 1960, turbine cooling was first used in a commercial aircraft engine. Since that time, there has been a very rapid rise in turbine inlet temperature that has placed an even greater emphasis on turbine cooling. A continuous improvement in high-temperature materials has also helped to increase the turbine inlet temperature. The cooling technique used during 1960s was single internal passage convection cooling. The air used for cooling was injected through the root of the blade and to the internal aerofoil.

Mozart Essays -- essays research papers

Julien Rouleau â€Å"The classical period produced more instrumental than vocal music, a wealth of serious and comic operas as well as vocal religious music also appeared during this time†(Ferris, 231). One of the best composer of this time was Wolfgang Amadeus Mozart. In this paper I will go through his childhood, his friends and family, and of course his music. Enjoy!!! Child of the Enlightenment The world that Wolfgang Amadeus Mozart entered ceremoniously in 1756 was brimming in change. Historians refer to this era as the Age of Enlightenment, one of unparalleled scientific, philosophical, and political ferment. Within Mozart’s lifetime it set in motion forces that would fundamentally alter life not only in his native, Salzburg, but also around the globe. The Enlightenment was not, to be sure, a democratic movement. In France, the absolutism of the Sun King, Louis XIV, continued under Louis XV and XVI. But in Austria, Empress Maria Theresa introduced a greater measur e of tolerance and freedom among her subjects, laying a foundation for the democratic revolutions that followed. Wolfgang’s father Leopold came from a family of Augsburg bookbinders. He received a solid Jesuit education, more intellectual than evangelical after a year at the Benedictine University in nearby Salzburg; Leopold stopped attending classes to pursue a career as a musician. â€Å"Leopold figured as Mozart’s most important first model. He taught his son the clavier and composition†(Mercardo 763). Wolfgang’s mother Anna-Maria brought as much talent to her 32-year marriage as did Leopold. Though deprived of a formal education, she was highly intelligent and quick-witted— qualities that attracted the sober and reserved Leopold. Only two of their seven children survived infancy. Wolfgang’s musically talented sister Nannerl was five years older. Yet in this painting, the 12-year- old looks like a spinster of seventy—complete with budding double chin. Wolfgang, too, looks far older than his 7 years, and controls the action from his place at its center. The Child Prodigy Indeed, Mozart marks the beginning of the Western fascination with the child prodigy. Dressed in the festive outfit given Wolfgang in 1762 by the Empress Maria Theresa, this boy of not quite seven years old looks, for all the world, like a miniature adult who has simply skipped childhood. â€Å"Mozart was keenly aware of his exceptional ... ...prodigy. The idealization of Mozart’s genius was complete by the end of the nineteenth century. Between 1762 and 1766, the Mozarts appeared at almost every major court in Europe. Wolfgang dazzled audiences with his ability to read difficult music at sight and to improvise Four of his operas—The Abduction from the Seraglio(1782), The Marriage of Figaro(1786), Don Giovanni(1787), and Cosà ¬ fan tutte(1790) —were premiered or performed in the prestigious Burgtheater. Then Mozart met Haydn; we do not know the occasion on which Mozart first encountered Joseph Haydn. In Haydn, he not only found a composer whose achievements were on a level with his own, but a warm and sympathetic friend in whom he could confide. In the autumn of 1791, Mozart’s health became progressively worse. He died on December 5, 1791, and was buried in a pauper’s grave. Critical thinking:  Why do you think Mozart’s instrumental music has been regarded as â€Å"ab solute music†? Why do you think was Mozart is Called a child prodigy? Suggested Further Listening: Opera: -The magic Flute -The marriage of Figaro Symphony: -Jupiter symphony, K.551 Piano Music: -C Minor Sonatas K.457 -D Major Sonatas K.576

Maya Angelo Essays -- biographies bio biography

If I could have the honor of meeting that one person it would be Maya Angelo. She was an inspirational and phenomenal woman of her decade. Not only was she an actress and poet, she was a mother too. Maya Angelo was a beautiful black woman in her time that stood for what was just. She experienced slavery, and even endured it. Her legacy and history is passed on through many of her books like â€Å"I know why the caged bird sings†, or through her poems such as â€Å"A raisin in the sun† and â€Å"phenomenal woman†. Thanks to her tenacity and considerateness this younger generation that I am growing up in can visit the past time and time again through her magnificent writings. Maya Angelo style of writing was very different from the many black authors I had read in the past. I say that because her choi...

Be Careful What You Wish for

BE CAREFUL WHAT YOU WISH FOR Drama practice. Revision. Homework. Writing essays– which is what I am doing now! So many things to do, so little time to actually do it. I am sprawled on my bed, along with my dictionary fiddling with my pen, deep in thought. Throughout that thousands of seconds I spent writing this essay, I often scrambled through the dictionary or Googled for words that would come in handy, composing this essay by scribbling word after word that was unreadable to everyone except myself.As my eyes darted to the untouched Chemistry homework due in two days, I rummaged through the strands of information that meandered at the back of my mind, in the hope of finding the answers to the questions regarding the practicality of what I was doing; why am I even writing this essay when I had other plans for today, like revising Chapter 2 of History. Sighing, I dropped my Carrera pen and clutched my iPod Nano–which I believed would be the antidote to my chagrin. Then, I stuffed my earphones into my ears willing my fingers to trace the song that I desperately needed at that moment–Time by Hans Zimmer.I was immediately taken in by the mellifluous song, the tender flow dictating my muscles to relax, the abstract beauty of it sinking my mind into a trance. Completely oblivious to the sounds of the outside world, I stared blankly at the four alphabets displayed on the screen- T I M E. Time. That was when realisation dawned on me. It’s strange how time, woven into our daily lives, casts a huge significance in every molecule of our being. It shows us no benignancy as it numbers our days, thus forcing us to endure the dull prospects of limitations, practicality and also the inability to maximise diversity and perfection at the same time.If only I could FEEL like I was divorced from time, savouring one moment to another, without having regrets or ‘I could have’ moments. For instance, if only I felt time held no sway over me, co uld I have kick-started my day with those Manchester United matches in the wee hours of certain mornings without wailing about the lack of sleep? Or I could have aroused my book-worm taste buds by dwelling on that stack of untouched storybooks which I purchased during the Big Bad Wolf Book Sale last year. Brushing the zig-zag thoughts off my mind, I flipped my iPod and gazed at the words engraved at the back of it-Live in Limbo!My mind propelled me to the thought of what that line meant to me. Limbo, as depicted in the movie Inception, is an unconstructed dream space of raw infinite subconscious which is more real than reality itself. Every second in Limbo would feel like an eternity, when in contrary, every second actually passes by with blinding speed. And when I meant Live in limbo, I was referring to it as a reminder to enjoy life and FEEL like I am in Limbo†¦ To FEEL that time really does crawl so that I can revel in the assumption that time would always be by my side like my Best Friend Forever, even when it is not.Right now, if I really was in Limbo, I wouldn’t be fretting or whining about time constraints. How I deeply wish that Limbo would be my reality. In that instant, I was transported into a seemingly endless and vast expanse of blankness, similar to that of being in an isolation tank. I knew where I was; Limbo. It was now my world, my reality. I had the power to create, filling my world with elements ranging from trees to buildings; imagination was the only tool I needed. I was even capable of creating a personal aeroplane but what I wanted at that very moment was to FEEL like I had control over time.In a split second, I had become someone who was born with an ‘imaginary silver clock’†¦The words ‘silver clock’ symbolising time that passes by unhurriedly, the word ‘imaginary’ referring to the fact that I only FEEL the seconds crawling pass and so it is only part of my imagination that time is not running out. I wasted no time in engineering my world–copying and pasting flashes of my memories into my surreal world. My subconscious mind, on the other hand, automatically filled up my world with projections of people I knew and never knew.My life went on as usual- going to school, attending drama practices, going for tuition, Face booking†¦But the difference was the pinch of conjury in it; that of the fact that I didn’t FEEL distressed, that I somehow held the key for doing anything I wanted as I felt time siding with me. I saw myself achieving goal after goal, consigned from oblivion that none of it was real; that I was in Limbo, and it was all part of my imagination. The youth in me got sucked out as every second passed- Until I got older and older and at the age of 28, I actually ran out of goals.I had a career, a house, a car that anyone would have dreamed of; all of it due to the grace of time being on my side. What else did I want after feeling like I had what I wanted and it seemed like an eternity had just whipped by? I wanted nothing any more. That was when my mind reeled into aimlessness, boredom, disheartenment. I had nothing else to do. However, even if I did, I would always feel time creeping by me, past me and somehow I would always achieve my goals, even if it was a mile apart from me. It was my world after all.I was bewitched by a spell on my mind indicating that time, for me would be like a space probe plummeting into the depths of the universe. As my mind free-fell into thought, questioning my well-being†¦I remembered. The memory came in thick and fast, like someone flipping through the pages of a diary as one image popped out after another vividly in my mind; That essay, that sixteen year old girl who had so many things to do. Where did all of that go? Stark reality hit me like a 10. 0 magnitude earthquake; I carried memories of twelve unreal years, I had grown older in my own imagination.After that, I would have to battle a poison called aimlessness for the rest of my life. That was only because I wanted to FEEL that time passed by slowly. Now I bemoaned wishing Limbo was my reality. The fear that gripped me; visceral, primal. The violent tremor on my shoulders jolted my eyes open. It was my mum. I was sixteen and young. Only ten minutes had passed by since I was in Limbo. I would never wish that Limbo was my reality–the promise to FEEL that time was on my side was an impossible cross to bear. Next time, I will be careful what I wish for because it might be a poison that I would not be able to deal with. (1199 WORDS)

Lyndon B. Johnson and Literacy Tests Essay

Over the last fifty years, a lot has changed when it comes voting and racial discrimination. The marches from Selma to Montgomery, Alabama have changed our history as a whole, forever. The intentions of the three marches were for African Americans to have the right to vote just like the white men. There were three different attempts for the marches from Selma to Montgomery: March 7, March 9, and March 21, 1965. The attempts to gain their voting rights came at a price they were beaten, clubbed, murdered, trampled upon and all kinds of things by the police during these marches. At least Even though the Civil Rights Act of 1964 had just been passed only a couple months before, African Americans were still being discriminated at the polls. They were not allowed to vote and if they were allowed to register than they were given literacy tests, which majority of them failed. Unlike during 1965 when the marches took place, African Americans did not have the right to vote, they were segregate d, discriminated upon, etc. Martin Luther King, the spokesperson or leader for the people during marches, wanted to march in a nonviolent manner to show the police and everyone else that they were not animals and they would not give up until they were given the rights that they deserve. The result of these marches came when President Lyndon Johnson address Congress involving the matter asking for legislation that would prohibit the polls in using barriers to prevent African Americans from voting. The Voting Rights Act of 1965 was passed that August 1965. This piece of legislation basically states that the government can’t discriminate during the voting process based on race and also prohibits the use of literacy tests as a requirement to vote because most black people during this time could neither read or write. Also under this act the United States attorney general had to challenge the use of poll taxes for local and state elections. Things in this, the twenty-first century, are much better than they were during Selma marches because there is a lot less racism and discrimination towards African Americans. African Americans have the same rights as white men, as do women, as written in the Bill of Rights. If Selma would have never occurred, or occurred in a violent manner rather than the nonviolent way it was, Africans Americans might not have the right to vote to this day, or worse. Also, without out the success of the Selma to Montgomery we would more than likely not have as many African Americans in political office as we do today. Times are so much better now than they were fifty years ago because African Americans now have 100% freedom and all of their rights. African Americans, as well as women, get to vote without having to worry about being discriminated against, as well as tested. Selma created leeway for a greater number of African Americans to become involved in political affairs at local, state, and national levels. Selma affected our political system a lot and without it we more than likely wouldn’t have some of the people we do in major positions in the government, such as President Obama.