Thursday, November 28, 2019
American Africans Action in the Struggle for Equality
These are protests that came to prominence in the course of 1950s, which raised concern against the incessant discrimination and racial segregation experienced by the American Africans and other marginalized groups in the southern America.Advertising We will write a custom research paper sample on American Africans Action in the Struggle for Equality specifically for you for only $16.05 $11/page Learn More Continued oppression against people of different color, race, politics, or even religion had inspired many young American Africans to join action in the struggle for equality (Chong 23). Some of the prominent figures in the Movement include Martin Luther King Jr, Malcolm X, W.E.B. Du Bois and Rosa Parks among others. Although the civil rights mass protest was officially formalized in the 1950s and 1960s, the fight for equality in various institutions of the U.S. had started long time ago. Community leaders in various segmentations of the society had sh owed resistance to the white supremacy and domination against the African Americans which had been abounded in some states. ââ¬ËEverydayââ¬â¢s Useââ¬â¢ written at the peak of the transformational movement, is a perfect expression and reflection of the issue of the aspects surrounding the civil rights movement. Set at the height of the social issue, the story is a real representation of the key aspects of the day. Here, the writer applies writing to highlight some of the main issues surrounding the Black Power Movement. Walkerââ¬â¢s purpose on the story is achieved through the creative formation of characters who symbolize the plight of blacks and women as observed during those times. The movement was initially facilitated by the progressive efforts of the descendants of African slaves who had always tried to resist the institution of slavery upon them. Regular protests and campaigns of resistance were some of the common characteristics associated with this movement. Civi l disobedience and activities of nonviolent demonstrations and protests were also common. Sometimes, these would bear crisis scenarios between government authorities and the activists resulting to confrontations. Although it took many years for the issues highlighted in the movement to be addressed, the protests had significant impact to the modern world. Many changes were realized owing to the pressure of the movement. For instance, the Civil Rights Act and the Voting Rights Act were introduced in the years 1964 and 1965, respectively thus granting all American citizens basic civil privileges, regardless of their race and ethnicity. Alice Walker is a renowned female activist who was born and raised at a time when the Civil Right Movements in South U.S. was taking shape. At the height of the transitional movement, Alice, then a college student at Spelman, was lucky to meet and rub shoulders with some of the prominent players in the movement, such as Martin Luther King Jr. This inspi red her to become one of the strongest female activists in the American history.Advertising Looking for research paper on american literature? Let's see if we can help you! Get your first paper with 15% OFF Learn More Her contribution in the struggle for human rights and equality has continued to raise strong impact to the world. According to Tuten, Alice is a woman with many records in life and her largest contribution in life can be perceived through her countless struggles against discrimination and oppression (126). ââ¬ËEverydayââ¬â¢s Useââ¬â¢ is just one of her many writings about race and gender which raised much alert in the civil rights movement. Racism, feminism and the many issues frequently raised by young American Africans whoââ¬â¢d tend to lose respect to the culture that gave birth to them are some of the issue that Alice explores in ââ¬ËEverydayââ¬â¢s Use.ââ¬â¢ As it would be observed, the story in this essay is Walkerââ¬â¢s respo nse to the social discourse of the 1950s and 1960s, when the civil rights movement took place. The writer has vividly expressed some of the issues that continue to plague modern American communities, as expressed through the lives of the characters in the story (Whitsitt 448). Economic, social, and political issues are illustrated in the story, through the family of the narrator, who is referred by the title of ââ¬ËMamaââ¬â¢ or Mrs. Johnson. The story strongly illustrates the big contrast between the narrator and Maggy, one of her two daughters who still share the same conservative life with her, and ââ¬ËWangeroââ¬â¢ or Dee, the educated daughter who scorns the culture that gave birth to her. As observed from this story, the writer has based the two sisters on aspects constituting her own character. Whereby Maggy represents her difficult childhood, Dee remains to be a vivid reflection of her latter life which is characterized by education and success; the two aspects tha t would enable her to take part in the civil rights movement. The two different positions represent the culture and the progress of the American Africans in mid-to late-twentieth-century times. The story is set in a time when the lives of American Africans were undergoing a radical transition. These groups of people were able to gain freedom of civil rights at last, through the glory of civil rights movement, after many years of oppression and discrimination from the whites (Gianturco and Tuttle 18). The final outcome reached on the story, is a representation of the results which succeeded the movement as American Africans started gaining recognition in various segments of the American society.Advertising We will write a custom research paper sample on American Africans Action in the Struggle for Equality specifically for you for only $16.05 $11/page Learn More This freedom would see the emergence of a new generation that has contradicting views about c rucial aspects of life. As a matter of fact, the writer has used the story to defend the legacy of her family and culture and to pay homage to the initial inhabitants of the South, where she grew up. Works Cited Chong, Dennis. Collective action and the civil rights movement, Chicago: University of Chicago Press, 1991. Print. Gianturco, Paola, and T. Tuttle. In her hands: craftswomen changing the world, New York: PowerHouse Books, 2004. Print. Tuten, Nancy. ââ¬Å"Alice Walkerââ¬â¢s Everyday Use.â⬠The Explicator 51. 2 (1993): 125-128. Print. Whitsitt, Sam. ââ¬Å"In Spite of It All: A Reading of Alice Walkerââ¬â¢s Everyday Use.â⬠Africanà American Review 34. 3 (2000): 443-459. Print. This research paper on American Africans Action in the Struggle for Equality was written and submitted by user Jazmin Bean to help you with your own studies. You are free to use it for research and reference purposes in order to write your own paper; however, you must cite it accordingly. You can donate your paper here.
Monday, November 25, 2019
Advanced Critical Writing The WritePass Journal
Advanced Critical Writing Introduction Advanced Critical Writing ). Alcohol is undoubtedly a public health issue and is involved in a high number of road traffic accidents and anti-social activities such as assault, as well as being associated with a number of chronic diseases including alcoholic liver disease and a range of cancers (Rehm et al., 2009; Schà ¼tze et al., 2011). Furthermore, the economic cost can be devastating with alcohol-related injury costing the National Health Service (NHS) around à £2.7 billion a year, based on 2006 to 2007 figures (NHS, 2011). Therefore, the Government should indeed feel some responsibility to tackle and reduce these figures if at all possible. The author argues that such a strategy as minimum unit pricing for alcohol will be an infringement on the British people, a violation of the free market economy and will cause moderate and responsible drinkers to pay for the ââ¬Å"crimes of a few.â⬠However, the author later contradicts themselves saying that ââ¬Å"boosting the cost [of alcohol] isnââ¬â¢t going to stop me drinking, itââ¬â¢s going to just leave me out of pocket.â⬠Here, the author has gone from the extreme and dramatic to an almost mocking of the proposed policy. It becomes unclear whether the author truly believes that the policy would severely affect the innocent or whether it would simply leave people short of a few pounds at the end of the month. This type of contradictory writing can also been seen elsewhere in the article. For example, the writer opens the article with a murky and sinister scene using evocative words and phrases such as ââ¬Å"swarmingâ⬠, ââ¬Å"staggeringâ⬠and â⬠Å"teenagers hunched over a bottle of Frosty Jacks.â⬠This use of language suggests that the author is disgusted and repelled by binge drinkers and the open consumption of cheap alcohol on British streets. However, the author quickly goes on to denounce Government attempts to tackle the problem as a ââ¬Å"crazy ideaâ⬠, once again sending out a mixed message to the reader. The author also argues against the claim that an increase in prices for drinks with a high alcohol content will put off the type of people who buy such drinks purely to achieve a state of drunkenness, namely individuals suffering from alcoholism. The author asks ââ¬Å"isnââ¬â¢t it their choice to drink alcohol?â⬠and suggests that it is unacceptable to hurt the average person financially by trying to price such individuals out of the alcohol market. This an extremely reductionist viewpoint, meaning that the author of the article is reducing the plight of an alcoholic to the result of just ââ¬Å"their choiceâ⬠rather than taking into account the plethora of reasons that can lead an individual down the destructive road of alcoholism, such as homelessness, debt or abuse. Such a view-point is potentially damaging as Spanagel (2009) has warned that a reductionist view of the causes of alcoholism can stand in the way of a better understanding of the underlying pathological p rocesses involved in such addictive behaviour. The author goes on to claim that implementation of a à £0.45 minimum unit price for alcohol is the result of the Governmentââ¬â¢s attempt to try and make revenue from people who can afford a price rise but are just inconvenienced by it. This is an extreme accusation and the author has failed to take into account the evidence that suggests otherwise. Namely that such a policy could have a positive effect on public health and the economy.à Using a price-to-consumption model using various data sources and based on 54 population sub-groups classed as harmful, hazardous or moderate drinkers, Purshouse et al. (2010) estimated that a à £0.45 minimum price unit for alcohol would reduce alcohol consumption by 4.5% and avoid 1,970 alcohol-related deaths.à A recent systematic review found that a price increase of alcohol by around 10% would lead to a reduction in consumption of alcohol by around 5% (Wagenaar, Tobler and Komro, 2010). Both of these studies have provided strong evidenc e that a minimum unit pricing strategy with alcohol would be effective in reducing hazardous alcohol consumption. Further strengthening the argument in favour of minimum unit pricing are doubts that other attempts to reduce alcohol consumption will be far from successful. In a recent editorial, McKee (2012) highlighted that the three main ââ¬Å"lines of attackâ⬠for tackling hazardous drinking consist of marketing, pricing and availability. Marketing and restrictions on availability are difficult to control, especially due to the lobbying power that many companies within the alcohol industry possess (McKee, 2012), and education-based interventions have been shown to be ineffective (Anderson, Chisholm and Fuhr, 2009) Therefore, pricing appears to be potentially the most effective and most easily manipulated element that the Government can utilise to tackle hazardous drinking. However, in addition to the positive effects that a minimum pricing policy has been predicted to have, there were also a number of drawbacks. For example, an increase in type 2 diabetes in young women was predicted due to a loss of the health benefits of moderate alcohol consumption and most of the reductions in harm would have been seen in chronic disorders in the over 45s, limiting the positive effect on the health and well-being of younger people (Purshouse et al., 2010). Furthermore, the figures produced by Purshouse et al. (2010) were based on a time period 10 years after policy implementation, suggesting that the benefit of a minimum pricing policy could be a long time coming. These drawbacks could be seen to support the authorââ¬â¢s claim that the Government would use a minimum pricing strategy primarily to increase their income, seeing as though implementation of the policy would be limited in its immediate and overall beneficial effects on public health. Furthermore, alternatives to minimum pricing such as increasing tax on alcohol, have also been found to decrease levels of alcohol consumption (Elder et al., 2010). However, the existence of potentially equally as effective strategies for tackling hazardous drinking does not automatically suggest a conspiracy by the Government to reap more revenue through a minimum pricing strategy. The author of the article disagrees with the claim that alcohol fuels crime and with the figure that intoxicated people are involved in causing around 5,000 avoidable crimes every year. However, it is well documented that alcohol is prolifically involved in crime. From 1998 to 1999, 70% of crimes were found to have involved alcohol (Home Office, 2001), with alcohol being a component in up to 70% of all stabbings and beatings, 40% of domestic violence incidents and 50% of child protection cases (Alcohol Concern, 2000). These figures are highly disturbing and the authorââ¬â¢s credibility is severely damaged in denying belief in such figures. The author ends the article with a rhetorical question by asking whether we would want ââ¬Å"to live in a free country where people live as their consciences tell themâ⬠or whether we want to try and ââ¬Å"control the behaviour of the poor by pricing them out of activities that we disapprove of?â⬠à A similar use of rhetoric can be seen throughout the article. For example, the author suggests that the next stage after minimum unit pricing may be an increase in theatre tickets to reduce the number of ââ¬Å"poorer, less educated people who might talk during the show.â⬠This is an example of hyperbole where the author is exaggerating in order to manipulate their audience and create a strong emotional reaction. Through the use of rhetoric, the author will hope to encourage their audience to ââ¬Ëcome roundââ¬â¢ to their way of thinking. However, the article would be far more persuasive if the author were to use more facts and empirical evidence to support their v iews. In conclusion, the article is well-written in terms of persuasiveness and in using rhetoric to create a strong emotional reaction in the audience. However, the author too often makes statements that contradict current empirical evidence without justification, which damages the credibility of the source. à References Alcohol Concern (2000) Britainââ¬â¢s Ruin: Meeting Government Objectives via a National Alcohol Strategy. London, UK: Alcohol Concern. Anderson, P., Chisholm, D. and Fuhr, D.C. (2009) Effectiveness and cost-effectiveness of policies and programmes to reduce the harm caused by alcohol. Lancet, 373, pp. 2234-2246. Elder, R.W., Lawrence, B., Ferguson, A., Naimi, T.S., Brewer, R.D., Chattopadhyay, S.K., Toomey, T.L. and Fielding, J.E. (2010) The effectiveness of tax policy interventions for reducing excessive alcohol consumption and related harms. American Journal of Preventative Medicine, 38(2), pp. 217-229. Home Office (2012) The Governmentââ¬â¢s Alcohol Strategy. London, UK: Home Office. Home Office (2001) Fighting Violent Crime Together: An Action Plan. London, UK: Home Office. Kuntsche, E., Rehm, J. and Gmel, G. (2004) Characteristics of binge drinkers in Europe. Social Science and Medicine, 59, pp. 113-127. McKee, M. (2012) Minimum unit pricing for alcohol ââ¬â the case for action is overwhelming. European Journal of Public Health, 22(4), pp. 451. NHS (2011) Statistics on Alcohol: England, 2011. London, UK: The NHS Information Centre. Purshouse, R.C., Meier, P.S., Brennan, A., Taylor, K.B. and Rafia, R. (2010) Estimated effect of alcohol pricing policies on health and health economic outcomes in England: an epidemiological model. Lancet, 375, pp. 1355-1364. Rehm, J., Mathers, C., Popova, S., Thavorncharoensap, M., Teerawattananon, Y. and Patra, J. (2009) Global burden of disease and injury and economic cost attributable to alcohol use and alcohol-use disorders. Lancet, 373, pp. 2223-2233. Schà ¼tze, M., Boeing, H., Pischon, T. et al. (2011) Alcohol attributable burden of incidence of cancer in eight European countries based on results from prospective cohort study. British Medical Journal, 342, d1584. Spanagel, R. (2009) Alcoholism: A systems approach from molecular physiology to addictive behaviour. Physiological Reviews, 89(2), pp. 649-705. Wagenaar, A.C., Tobler, A.L. and Komro, K.A. (2010) Effects of alcohol tax and price policies on morbidity and mortality: a systematic review. American Journal of Public Health, 100, pp. 2270-2278.
Thursday, November 21, 2019
Questions - part II Essay Example | Topics and Well Written Essays - 2250 words
Questions - part II - Essay Example In this paper, we will focus on two philosophers; Boethius and Machiavelli. Through examining the two philosophers, we will be able to understand the main tenets of the ancient modern debate. Part A The main tenets of the ancient modern debate revolve around several differences on the subject of human nature. It is clear that different philosophers have presented diverse thoughts and opinions regarding the so called human nature. Building on this point of view, there has been a developing code of ethics emerging from such theorists and what people accept as true in the present day. It is worth examining Boethius view points on the subject and compare them with Machiavelliââ¬â¢s accordingly. Part B From a literal point of view, Boethiusââ¬â¢s most excellent known work is referred as the consolation of philosophy. He wrote this work whilst in prison while awaiting his execution. Boethius finds himself in jail. At first, he is profoundly upset. The cause of his suffering emerges f rom his enduring project, effort to conserve ancient classical knowledge, specifically philosophy. His work represents an imaginary conversation between himself and philosophy. In that case, philosophy is personified as a woman. The arguments in this scenario are that, in spite of the apparent disparity of the humankind, there is, within platonic fashion, a high power and everything besides is secondary to such divine providence. Despite Boethius suffering while in exile, it is recorded that philosophy appears and attempts to ââ¬Å"cureâ⬠his suffering. Philosophy, which is personified as a woman, does this in various ways. First of all, she does this by reminding him of what he once knew about the true nature of human beings; the nature of fortune, the nature of happiness, and the limits of politics to provide happiness (Boethius 49). In Boethiusââ¬â¢ argument of the nature of fortune, happiness, and the limits of politics to provide happiness, he agonizes over the profess ed inappropriateness between the subsistence of God and the wickedness that exists in the earth. What is more, he agonizes between the existence of God and the superficial ethical inversion of the creation. In responding to such issues, Boethius declares that Godââ¬â¢s kindness and Godââ¬â¢s obligation to honesty does not necessitate that God get rid of every instance of evil. Then again, Boethius presents argument that there are at least different examples of goodness that appear to have need of the likelihood of some wickedness, ethical education with regards to the free will of humans and the true nature of happiness. Moreover, Boethius presents an argument that the nature of evil as self-destructive to wrongdoers and the nature of the ultimate good as the one which, every person naturally look for, an indication that the earth is not decently inverted. As a result, Boethius would dispute the reality of premise in the modern formulation of the issue of evil (Boethius 54). I n his argument for the compatibility of the subsistence of God with the continuation of evil, he provides explanations as to why God would allow occurrences of evil and not do away with them. As a character in the Consolation, he seems to take consolation in such discoveries. Reflecting on the above discussion, it is worth contemplating that the lady philosophy brings to a n end the dialogue with both caution and encouragement, ââ¬Å"
Wednesday, November 20, 2019
White Paper Assignment Example | Topics and Well Written Essays - 250 words - 1
White Paper - Assignment Example Therefore, nurses are advised on how to avoid misuse of social media. Misuse would result into a compromised quality of their service delivery (Gagnon & Sabus, 2015). The white paper puts emphasis on the fact that patientsââ¬â¢ personal treatment history should be safeguarded by nurses. The information can only be shared for medical purposes with the consent of the patient. Therefore, social media should not be used as a platform for sharing private medical information inappropriately. The health Act on Insurance Portability and Accountability gives the necessary guidance on patient privacy regulations (Hader & Brown, 2010). The white paper is a major boost to the efforts of the policy to improve health care service quality and safety. If the provisions of the paper are adhered to, the management and safe-keeping of patient records will improve. Breach of patient confidentiality will be avoided and good professional conduct will be a major code of operation. If nurses pay attention to their conduct, the services they provide will meet the standards that satisfies patients. Consequently, the quality of health care service will be improved (Henderson & Dahnke,
Monday, November 18, 2019
Genetic Modification Research Paper Example | Topics and Well Written Essays - 1250 words
Genetic Modification - Research Paper Example However, genetic modification is most common in plants than in animals. Genetically modified foods are developed for various reasons. For example, to improve the quality of some foods and to some other foods, it is done to prevent the chances of allergies after consumption. Some of the genetically modified foods include; soybean, tomatoes and corn plants as will be discussed in this paper, among others. Although the technology gives a lot of promises for consumption of these foods, there are however some risks associated with the technology just like any other new technologies (Buzzle.com, 2012). Soybeans The genetically modified soybeans are fast growing and resistant to pests and herbicides. This leads to increased production hence food security to the ever-growing population as compared to the traditionally grown crop. The fact that this crop is tolerant to herbicides implies that it cannot be affected by the herbicides once sprayed to the weeds. Therefore, the farmers end up usin g strong herbicides, which are sprayed only once in order to destroy the weeds. This does not require a lot of herbicides because the herbicide once used totally destroys the weeds resulting to reduced environmental pollution. Genetically modified soybeans are drought resistant and can be grown in places with poor soils. This means that the crop can withstand harsh climatic conditions as well as be grown in places with infertile soils where agricultural production is poor with the normal crops. By growing the genetically modified soybeans in such places utilizes the unproductive lands, earning the residents income. Moreover, this food has high nutrient content with more vitamins and minerals, and tastes much better as compared to the traditionally grown crops. This, makes them more preferable to most people than the traditionally grown ones (Anslow, 2008 & Buzzle.com, 2012). Despite the advantages associated with genetically modified soybeans, recent research studies has shown that the growing of genetically modified soybeans may lead to the transfer of herbicide resistant genes to non-target species like the weeds through cross-breeding. This will make the weeds become herbicide tolerant as well. Moreover, chances of cross-pollination to the unmodified crops are also high in such a situation. In many countries where genetically modified soybeans are grown, the genetically modified soybean product is not labeled, as manufactures fear losing customers, which may ultimately interfere with their overall business. This denies the consumers the opportunity of making their own choice on whether to consume these foods or not since the products are not labeled in the market (Buzzle.com, 2012). Apparently, as Anslow (2008) points out, genetically modified soybeans can thrive under any climatic condition giving high production with high nutrients and requires less labor since one does not have to use tillage in order to remove weeds especially in big acreage of land, bu t can just use a strong herbicide instead, to destroy the weeds. Despite these, the negative effects should not be overlooked. For instance, in the long run the weeds also turn to be tolerant to herbicides hence becoming ineffective. Moreover, the consumers end up consuming genetically engineered products unknowingly, because the labels are not included and this may lead to long-term health problems, which is not their fault. Therefore,
Friday, November 15, 2019
Material manufacturing and analysis of engine crankshaft
Material manufacturing and analysis of engine crankshaft The report outlines the detail of material and manufacturing process selection exercise carried out on a typical car engine camshaft. Camshaft being one of the most important engine components requires careful selection of material. Moreover, owing to its specialized operation, the required geometry is relatively complex and certain improvements in mechanical properties are required to be introduced during manufacturing. This calls for and rather complex manufacturing route to be followed. The report initially mentions the operation of the component and describes its required characteristics. The material and manufacturing process selection is then carried out based on the intended use. A detailed description is provided in the end about the selected manufacturing route. INTRODUCTION The crankshaft is the part of an engine which converts reciprocating motion of the pistons into a rotary motion. The rotary motion has the advantage that it can be used rotate the wheel of the car. Crankshaft is an essential component in reciprocating engines because, rotary motion is simpler to mobilize the vehicle in which reciprocating engines is installed. Crankshafts are equipped with crankpins and additional bearing surfaces. The axis of bearing surfaces is offset from the crank. During operation, crankshafts are subjected to following mechanical stresses: Bending stresses due to up and down movement of pistons. Torsion stresses due to rotation of crankshaft and transmission of force to drive train, which subsequently transmit motion to various services. Owing to reciprocating motion of the pistons, bending forces on crankshaft are always cyclic in nature. Therefore, the stress behavior is further complicated due to constant fatigue factor hence necessitating higher fatigue resistance in the component. Friction of bearing surfaces is also important during the operation. The piston arms have to slide past the crankshaft surface. Therefore roller bearings are equipped between the sliding surfaces. However, as rpm of a typical engine reaches 4000-5000 during normal operation, an efficient lubrication is extremely essential for bearing. The crankshaft therefore contains holes for lubrication system. Operating temperature inside the engine is extremely high. Therefore, the material should be such that it retains required mechanical properties at elevated temperature. In order to suppress pulsating behavior of reciprocating engines, crankshafts generally connect to flywheel. In certain cases, a vibration damper is also installed at the opposite end to reduce vibration. Figure No 1: Engine Crankshaft Along with Connected Parts The analysis presented in this report focuses on crankshaft manufacturing which is feasible for large scale manufacturing. Figure No 2: CAD Drawing of the Camshaft MATERIAL SELECTION Based on the stress imposed on the component during the operation, operating temperatures and intended operation, the material to be selected for this component should posses following characteristics: The material should be strong in bending It must have excellent fatigue resistance. The material should be light weight so that it has small value of moment of inertia and transmit motion more efficiently. It must have lesser coefficient of thermal expansion so that the component can retain its original dimension at varying temperatures. The material should be easily machineable so that it can take complex shape (as required for the geometry of crankshaft) easily and without developing unnecessary stresses. After carrying out an extensive research of materials, following materials were short listed for crankshaft: Aluminum Copper Steel Aluminum Aluminum is an excellent machineable metal. It is light weight and can take complex shapes easily. Moreover, it can absorb vibration very efficiently. However, the metal has lower modulus of elasticity and higher coefficient of thermal expansion. Therefore, it will be subjected to larger strains at higher stresses and high temperatures. Moreover, it does not possess good resistance to fatigue loads and corrosion. Copper Copper possess very good corrosion resistant properties. It is easily machineable and has high strength. Moreover, it can possess good surface finish which proves helpful in achieving reduced friction properties. However, the biggest disadvantage of copper is that it is no corrosion resistant. Corrosion rate is significantly higher at higher temperature. It is therefore, not considered suitable for the intended use. Steel Steel is another option to be used as a material for camshaft. Steel is a better choice because, it possess excellent mechanical characteristics which suits best with the operational requirements of engine camshaft. It has the highest modulus of elasticity. It is tough, strong, easily available, cheap and it has very less coefficient of thermal expansion which makes it best suited for high temperature operation. However, steel itself has a large number of variants which posses large range of properties. Therefore, selection of most appropriate type of steel is also very important. An option for crankshaft material is carbon steel. However, these steels require additional heat treatments to acquire required level of strength. Iron crankshaft is also an option. However, iron cannot take higher loads therefore, iron crankshafts are suitable for low output engines where stresses are lower. They have the advantage of being low cost. In fact, the most widely used material for crankshaft worldwide is Vanadium Microalloyed steel. It has following advantages: Vanadium Microalloyed steel can be air cooled after reaching high strengths without further heat treatment. However, surface hardening is required for the bearing surfaces. Low alloy content also makes the material cheaper than high alloy steels. MANUFACTURING ROUTE SELECTION Crankshafts can be manufactured using following methods: Machining Forging and casting These processes are discussed separately in the lines below. Machining Process Machining is yet another process which can be used to manufacture crankshafts. Crankshafts can be machined out of a billet, often using a bar of high quality vacuum re-melted steel. Machining process has following advantages: Higher quality of steels, which cannot be forged can be used through machining process. No expensive tooling is required for machining process. Extremely high quality crankshafts can be manufactured. However, machining process also has following disadvantages: It is a highly expensive process because; it generally uses high quality material. Moreover, a significant quantity of material is also wasted during machining process. Additional heat treatments are required to get required material properties. Forging and Casting Process Forging is the most widely used process for manufacturing crankshafts today. It is due to the following reasons: The component has lighter weight The forged shafts have better damping characteristics More compact dimensions can be achieved The camshaft is a complex component. Therefore, it is not feasible to manufacture the complete component using a single process. Instead, the manufacturing process comprises of multiple steps encompassing various machining, milling, forging and heat treatment operations. The details are outlined in the next section. DESCRIPTION OF SELECTED MANUFACTURING ROUTE Following is the detailed outline of manufacturing process selected for the camshaft: The raw steel are required for a diameter range from 2.125 to 2.5 and 20ft in length (Figure No 1 in Appendix A). The raw steel bars are then turned on a lathe to remove the rough surface and then cut into the proper lengths depending on the engine size (Figure No 2 in Appendix A). Subsequently, the steel begins the process of becoming a camshaft as both the journals and lobes are cut and evenly spaced out. The Camshafts are then stack up and are prepared for the copper plating (Figure No 3 in Appendix A). The copper plating is done to keep the steel from becoming brittle and helps straighten the camshaft after the heat treating process. Once the copper is applied, the journals are lathe down to the thickness that is needed (Figure No 4 in Appendix A). The surfaces are then finished. Next, a special lobe milling machine is used to create the lift for the cam. These CNC machines use computerize programs that allow the manufacture to create the desired lobe and are precise at 0.0001 of an inch (Figure No 5 in Appendix A). Once the cams are roughly cut, they are placed in a furnace for heat treating. This process hardens the steel making the cam less likely to warp or snap when put under the stress of an engine. After the heat treating, the journals go through their final grounding stage and are milled to the correct dimensions (Figure No 6 in Appendix A). Following the journals are the lobes. They are grounded and polished to provide a smooth surface which reduces friction in the engine, freeing up horsepower. The last process uses a computerized scanner that checks the tolerances on the cams. Making sure that every lobe and journal are exactly the same.
Wednesday, November 13, 2019
Can You Hear Me Now? :: Analysis, Sherry Turkle, Rocler-Gladen
Are technology and the media shedding the very fabric of the existence we have known? As technology and the media spread their influence, the debate over the inherent advantages and disadvantages intensifies. Although opinions vary widely on the subject, two writers offer similar views: Professor Sherry Turkle, director of the MIT Initiative on Technology and Self, in her article ââ¬Å"Can You Hear Me Nowâ⬠and Naomi Rockler-Gladen, who formerly taught media studies at Colorado State University, with her article ââ¬Å"Me Against the Media: From the Trenches of a Media Lit Class.â⬠Turkle asserts that technology has changed how people develop and view themselves, while at the same time affecting their concepts of time management and focus (270). Similarly, Rockler-Gladen believes media and its inherent advertising have had a profound effect on the values and thinking of the public (284). I could not agree more with Professor Turkle and Ms. Rockler-Gladen; the effects tech nology and media have worried and annoyed me for quite so time. The benefits of technology and media are undeniable, but so then are the flaws. People are beginning to shift their focus away from the physical world to the virtual world as they find it easier and more comfortable. The intended purpose of technology and media was to be a tool to improve the quality of life, not shackles to tie people to their devices. I no longer recognize this changed world and long for the simple world of my youth. Turkle argues that technology has fundamentally changed how people view themselves and their lives (271). She reports that, ââ¬Å"BlackBerry users describe that sense of encroachment of the device on their time. One says, ââ¬ËI donââ¬â¢t have enough time alone with my mindââ¬â¢; another, ââ¬ËI artificially make time to thinkâ⬠¦Ã¢â¬â¢Ã¢â¬ (274). Her point is that people have to make a deliberate choice to disconnect, to exist in their own mind rather than the virtual world (Turkle 274). Another point Turkle brings up is that in this technologic age children are not learning to be self- reliant. Without having the experience of being truly alone and making their own decisions, children are not developing the skills they once did (Turkle 274). As Turkle reports, ââ¬Å"There used to be a moment in the life of an urban child, usually between 12 and 14, when there was a first time to navigate the city alone. It was a rite of passage that communicated, ââ¬Ëyou a re on your own and responsible.
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