The South China Sea Island Disputes

The South China Sea Islands Disputes Name of student Name of institution The South China Sea Island Disputes Introduction China’s rise to the status of a global economic power has been viewed with both skepticism and hope by her neighbors. Skepticism by countries wary of China’s history of aggression as far as territorial disputes are concerned, and hope by countries wishing to benefit from trade partnerships with China. However, it is China’s activities in both the south and East China seas that have got her neighbors worrying. In the 1970s and 80s, China was concerned with marking her terrestrial borders with countries that surround her.It was in the process of defining her borders that China’s military power was felt. There were border skirmishes between China and several of her neighbors including India and Russia. Having secured her terrestrial borders, China’s attention shifted to her maritime territory and its security. She embarked on the ac quisition of islands within the East and South China Sea. It is this expansion mission into the sea that has seen many disputes arise between China and her neighbors who lay claim to the same islands. This expansion strategy has seen disputes erupt between China and her neighbors who lay claim to islands she has acquired.As early as April 2012, the Philippine and Chinese militaries nearly faced off over an island known as Scarborough Reef. In the East China Sea, China has had a long dispute with Japan and Taiwan over the ownership of a group of islands known as Senkaku in Japan and Diaoyu in China. As late as 2012, Japan and China had a standoff over these islands. Although both countries have tried to diffuse tensions over this issue, the threat of conflict remains real especially with the involvement of the United States. Thesis Statement Recent diplomatic spats between China and her neighbors have increased tensions in the South East Asia regions.Such standoffs make the threat of conflict in the region all too real especially with the involvement of external actors such as the United States. However, it should not be lost on scholars that China’s claim to various islands in both the South and East China Sea is the major contributor to these tensions. This is evidenced by the recent standoffs between China and Japan over the Diaoyu/Senkaku group of islands in the East China Sea, as well as tensions with the Philippines over the Scarborough Reef and Spratly islands in the East China Sea.This paper offers a background to the disputes between China and her neighbors over these islands, and particularly Diaoyu/Senkaku. It will further investigate the domestic factors influencing China’s assertiveness in both the South and East China Sea and her claim to these islands as well. Finally, the paper will attempt to paint some probable outcomes of these conflicts while at the same time offering possible solutions. Background to the Disputes Diaoyu/Senkak u Dispute. A look at the world map will not clearly show the location of the Diaoyu/Senkaku islands. This shows how tiny these islands are.They consist of five volcanic islands and three outcroppings located 400 km west of the Japanese island of Okinawa and approximately 170 km northeast of the republic of Taiwan (Lohmeyer, 2008). Although they are administered by Japan, there is no human habitation in these islands. Imperial China is said to have been the rightful owner of the Diaoyu/Senkaku islands before 1895. In fact, the name Diaoyu in Mandarin stands for ‘fishing ground’ or ‘fishing platform’ (Lohmeyer, 2008). The Japanese name, senkaku, means ‘sharp point’, and was given to the islands by the 19th century Japanese explorer, Kuroiwa.However, China lost the islands as well as Taiwan to Japan in the Sino-Japanese war of 1895 (O’Shea, 2012). The islands remained in Japanese hands till the end of World War II when they fell under the U nited States mandate, as did the whole of Japan after losing the war. Additionally, the ownership of Taiwan reverted back to China at the end of the Second World War but not these islands. It is important to note that Taiwan and the People’s Republic of China lay claim to the islands on the basis of history. In other words, both claim that the islands have historically been part of their territory until they were captured by Japan in 1895.However, none of these countries made an issue of the islands ownership until oil deposits were discovered in the East China Sea in 1968. By the time the U. S returned the ownership of the islands as well as Okinawa to Japan, Tensions were already building up (O’Shea, 2012). Japan lays claim to the islands based on the United Nations Convention on the Laws of the Seas (UNCLOS) principle of Continuous Peaceful Administration. Although the dispute over the islands intensified after the U. S handed them over to Japan in 1972 (Beukel, 201 1), it was not until the 1990s that this dispute gained prominence.According to O’Shea (2012), Taiwan and China were angered by media reports which revealed that a Japanese right wing group had constructed a lighthouse in Diaoyu/Senkaku, and that the group had applied to the Japanese Coast Guard to recognize it as a government property. The protests that ensued in both China and Taiwan served to whip up nationalist sentiments against Japan. China responded two years later by enacting a maritime law called ‘the law of the People’s Republic of China on the Territorial sea and Contiguous Zone’.It is article two of this law that rattled Japan and Taiwan since it states that the People’s Republic’s territory included â€Å"†¦Taiwan and all islands appertaining thereto including the Diaoyu islands† (Lohmeyer, 2008). Despite Japan’s diplomatic protests, China has not changed this part of the law. The issue of the lighthouse recogn ition surfaced again in 1996 with the Japanese government giving it a serious thought. Taiwanese and Chinese activities reacted by setting sail for the islands. Attempts by Japanese coast guards to arrest the activities resulted to the drowning of some of the activists.This incident forced Japan to allow the activists to land on the islands. Japan also shelved the lighthouse recognition issue (O’Shea, 2012). In September 2010, the dispute over the islands erupted with news of a collision between two Japanese coast guard ships and a Chinese fishing trawler (O’Shea, 2012). The crew of the trawler was apprehended by the Japanese coast guard and later released, save for the captain. When China learned that the Japanese authorities planned to charge the captain in court, it suspended the exportation of rare earth to Japan among other severe measures (Beukel, 2011).The situation was eased by the release of the Chinese captain. The situation is not helped by Tokyo’s mo ve to nationalize some of the islands in September, 2012 which was condemned by China. China even conducted naval exercises in the waters near the islands, a move Japan termed as provocative. Other island disputes involving China. According to a report by the International Crisis Group (2012), the threat of war in the South China Sea is becoming real with each passing day. This is as a result of China’s growing assertiveness in staking her claim to various islands in that part of the world.These disputes pit china with countries such as the Philippines, Vietnam, Taiwan, Indonesia, Malaysia and Brunei Darussalam (Buszynski, 2012). The disputes arise from the fact that the islands claimed by China are said to be within the Exclusive Economic Zones of the above mentioned countries. Additionally, there are reports of oil and natural gas deposits having been discovered in the waters surrounding many of these islands. These reports precipitate the disputes further. Although maritim e disputes exist between China and her South China Sea neighbors, it is Vietnam and the Philippines that have shown resolve in defense of their claims.The international Crisis Group (2012) reports that Vietnam and China have twice gone to war over Chinese occupation of islands which Vietnam says are within her Exclusive Economic Zone (EEZ). The first war took place in 1974 when China occupied the Paracel islands. Although Vietnam is said to have lost this war, she did not hesitate to engage her gigantic neighbor in another war in 1988. This was as a result of China’s occupation of the Spratly islands. As late as 2011, there were tensions between the two countries over China’s naval violations of Vietnamese waters.In order to counter China’s aggressive moves, Vietnam has embarked on modernization of its military and forging of closer ties with the U. S, china’s military rival in the Asia-pacific region. Resolve by the Philippines to resist China’s o ccupation of islands within Philippines EEZ was witnessed in April 2012 when the two countries were involved in both military and diplomatic standoffs. The international Crisis Group (2012) reports that this diplomatic crisis was occasioned by Chinese naval deterrence of Philippine naval patrols from apprehending Chinese fishermen in the Scarborough islands.Obviously, the fishing activities by the Chinese were illegal, and China did not have to respond as forcefully as she did. Furthermore, the Philippines, together with Malaysia, have disputed China’s claim to the Spratly archipelago (Buszynski, 2012). With the Philippines and Vietnam showing more resolve in their disputes with China, the prospects of peace in the region dwindle with each passing day. Domestic Factors Influencing China’s assertiveness in the South China Sea China’s growing assertiveness in the South China Sea is influenced by various domestic factors.They include Chinese nationalism, the need t o secure energy resources, local economic interests, competing law enforcement agencies, and the ineffectual coordination of various government actors. Ineffectual coordination of various government departments by the central authority is made difficult by the number of departments within the government. These departments are huge in number and have, on various occasions, overstepped their mandate. The International Crisis Group (2012) reports that some of these departments have assumed the role of the foreign affairs ministry.A good example would be the way the Bureau of Fisheries boats have been used to guard the waters around the disputed islands. The promotion of tourism abroad should be done through the ministry of foreign affairs, but this has not been the case. This task is undertaken by the National Tourism Administration which goes as far as marketing tourism in disputed islands (Crisis Group, 2012). Obviously, this points to weaknesses within the ministry of foreign affair s and the factional divisions within the Chinese Communist Party.Apart from ineffectual coordination in government departments, there is competition among law enforcement agencies in China. These competing interests and the agencies’ uncoordinated activities have served to heighten tensions in the South China Sea. While the China Marine Surveillance is charged with patrolling the South China Sea, the Bureau of Fisheries Administration also assumes this role. It is the latter agency that has been involved in many of the disputes involving China and her neighbors. Patrols of China’s waters should be left to her naval forces.Diaoyu/Senkaku became a major issue in the Sino-Japanese relations after the discovery of oil resources in the waters around the islands in 1968. Therefore, it would be correct to mention that the major driving factor for China’s assertiveness over this dispute is domestic energy needs. Buszynski (2012) reports that China people became the seco nd largest consumer of oil in the world in 2009. By the year 2030, China will most probably be the overall largest consumer of oil in the world. This energy need is driven by its industries.It would, therefore, be expected that the People’s Republic would aggressively assert its claim to the South Asia Sea Islands which have been reported to contain large deposits of hydrocarbons. These oil reserves are estimated to be in billions of barrels. There are also natural gas deposits underneath the seabed near Diaoyu/Senkaku islands. Another domestic factor that has been cited as influencing China’s assertive attitude in the South China Sea is Chinese nationalism. Beukel (2011) observes that there has always been resentment for Japan among the Chinese public.This resentment stems from the atrocities committed against the Chinese by the Japanese between 1895 and the Second World War. Therefore, any hostility between China and Japan whips up more nationalist sentiments among t he Chinese public. Analysts have also pointed out the fact that the Chinese leadership has at times whipped up nationalist sentiments as a way of promoting patriotism (Buszynski, 2012). Local economic interests have also contributed to the tensions between China and her South China Sea neighbors.The International Crisis Group (2012) reports that the southernmost Chinese provinces of Hainan and Guangdong directly contribute to the assertive behavior witnessed from China in the recent past. These provinces have bypassed the central government in their actions against China’s neighbors such as Vietnam and the Philippines. In other words, the provinces seek to perform better than others economically. How China is Likely to resolve these Disputes China’s activities in the South China Sea have angered many of her south East Asia neighbors. The latest altercations in the South China Sea have heightened tensions in the region.However, the dispute with Japan over the Diaoyu/Sen kaku islands presents a delicate situation since the United States plays a pivotal role in the defenses of many nations in the South China Sea region. Beukel (2011) observes that Sino-Japanese relations are quite complex because both countries are strong partners. It is encouraging to note that while the Diaoyu/Senkaku dispute has existed, it has not broken the ties between the two nations. However, as long as the United States keeps on getting dragged in the South China Sea on the side of one disputants, China’s position is likely to harden.Disputes between China and her neighbors such as the Philippines and the Vietnam can easily be solved through fora like the Association of South East Asian Nations (ASEAN). However, the situation is precipitated by the standoffs between the disputants. Furthermore, the situation is likely to be precipitated by the military build ups in the region. Conclusion China’s activities in the South China Sea have been viewed with wariness b y her South East Asia neighbors. The long standing dispute over the long Diaoyu/Senkaku islands has been at the center of attention of the Sino-Japanese relations.The frequent flare ups in this region have been blamed on China’s strategy to expand its Exclusive Economic Zone. There are several domestic factors driving China’s quest for a larger share of the South China Sea. These include heightened Chinese nationalism, lack of coordination of the various Chinese government departments, and competing interests among the Chinese law enforcement agencies. Additionally, China’s domestic energy needs as well as local economic interests serve to heighten tensions in the South China Sea.There have been various speculations as to the directions that these disputes will take. However, these disputes can be resolved through regional fora such as the Association of South East Asian Nations, ASEAN. The situation will, however, be escalated by grand standings and continued m ilitary build ups. References Beukel, E. (2011). Popular Nationalism in China and the Sino-Japanese Relationship: The Conflict in the East China Sea: An Introductory Study. Copenhagen: Danish Institute of International Studies, DIIS. Buszynski, L. (2012).The South China: Oil, Maritime Claims, and U. S. -China Strategic Rivalry. The Washington Quarterly, 35 (2), 139-156. International Crisis Group (2012). Stirring Up the South China Sea (I). Brussels: Author. International Crisis Group (2012). Stirring Up the South China Sea (II): Regional Responses. Brussels: Author. Lohmeyer, M. (2008). The Diaoyu/Senkaku Islands Dispute: Questions of Sovereignty and Suggestion for Resolving the Dispute. Canterbury: Author. O’Shea, P. (2012). Sovereignty and the Senkaku/Diaoyu Territorial Dispute. Stockholm: EIJS, Stockholm School of Economics.

How are women portrayed in The Millers Tale Essay

The Miller’s Tale was written and is set in medieval England, a time when women had much fewer rights than men, and were more or less just owned by their fathers, and then by their husbands when they got married. 17th century United States in The Crucible has a slightly different society but also has the similar male dominance. The Handmaid’s Tale is set in a dystopian future where women are also heavily dominated by men, but in a completely different way. This essay is about the ways that women in general are portrayed and perceived in these three stories, as well as touching on the characters of the individual women in these tales. The Miller’s Tale is one of the stories from the Canterbury Tales series, all written in poetic form, by Geoffrey Chaucer. These tales in the series are all told by different pilgrims, who are also fictional, so this uses a story-within-a-story literary device. Their tales are part of a contest to entertain each other on their pilgrimage from Southwark to Canterbury Cathedral. In The Miller’s Tale, it is the miller’s turn to tell a tale, and he tells the story of a devious young student called Nicholas, who is attracted to the much younger wife of a carpenter, his neighbour, and plots a cunning plan to sleep with her. He does this by telling the dim and simple carpenter that a flood is coming, and that he must tie some tubs to the ceiling of his home for the three of them in order to keep them safe. Whilst the carpenter is away at work on these orders, Nicholas takes the carpenter’s wife Alison downstairs and manages to seduce her until she very willingly has sex with him. Alison from The Miller’s Tale is eighteen years old, and described as passionate and highly attractive. Her faithfulness in marriage to her husband is very questionable when she allows herself to be easily taken in by this other man, her neighbour, and commits adultery with him without much care for her own husband. Near the beginning of the Miller’s Tale, there is a clear, physical description of Alison, being a lively woman who might want to have an affair. For she is â€Å"wilde and yonge†, meaning that her behaviour is rather uncontrolled, and her older husband is jealous and possessive of her. The miller describes her as having a â€Å"body gent and smal† as a weasel’s, meaning that she has an attractive slim figure, and that suggests that she is also a very sly character just like a weasel. Alison is also vain and very concerned about her appearance. She is selfish and cares more about herself than of other people, and she does not even think much of all the men that take a strong liking to her. She has established herself as a not at all a likeable character in this story. The fact that she sleeps with Nicholas right in her very own marital home, whilst her own husband is just upstairs at work at the very same time, must show how very daring she is, because he could have easily come downstairs and catch them in the act. But it could also mean that she does not actually really mind or care much about the carpenter’s feelings or whether he knows that she is being unfaithful to him or not. We feel some sympathy for the carpenter, who is being conned like this by two people, as well as being cheated on by his wife and having to bear the shameful title of a â€Å"cuckold†. Alison is certainly one to take risks in exchange for her own selfish sexual desires, going against the female stereotypes of the time by being rebellious and free-spirited and instead of being faithful and modest like a woman should be in her time. Alison from The Miller’s Tale is a lot like Abigail Williams from The Crucible. They are similar ages, and are both selfish and sexually immoral women who both have illicit sexual affairs and go against societal and moral rules that are expected of them for their own personal gain and pleasure. Also, neither Alison nor Abigail show any shred of remorse for their sinful actions. Where Alison goes behind her albeit dim husband’s back to sleep with her neighbour Nicholas, she is in turn fulfilling his desiring lustful plan. Sex outside of marriage was very wrong in her time, let alone committing adultery. Alison might have just married the carpenter for the sake of security, since he is described in the story as a â€Å"rich gnof†, but obviously cannot control her extramarital sexual urges and is very open to acting on them whenever the chance arises. Seventeen year old Abigail betrays her position as a house servant in the Proctor’s home by having an affair with John Proctor whilst he is still married to his kind wife Elizabeth, who happens to be ill at the time the affair occurs. However, there is much more to Abigail than involvements in adultery, as this leads to her seemingly falling in love and becoming obsessed with John Proctor. She says to him in Act One before the trials: â€Å"I know how you clutched my back behind your house and sweated like a stallion whenever I come near†¦ It’s she put me out, you cannot pretend it were you. I saw your face when she put me out, and you loved me then and you do now†. Abigail has seriously formed an impression that John is just as infatuated with her and she is with him, even though he constantly denies it and tells her she is speaking a â€Å"wild thing†. So at the very start of the play, she is casting a spell to kill Elizabeth so that she can be out of the way for herself and John to be together, as she believes that Elizabeth is the only person in her way of having John. We can sympathise a little with Abigail, as we know she has had a very troubled past. She is an orphan, who had watched both her parents being viciously murdered by Indians one night a long time ago. She reveals this in Act One, after ordering the girls to lie about their activities in the woods, she viciously threatens to get them in the night, and in her own words says â€Å"you know I can do it: I saw Indians smash my dear parents’ heads on the pillow next to mine, and I have seen some reddish work done at night, and I can make you wish you had never seen the sun go down! â€Å". This traumatic event that was imposed upon her at such a young age does provide some explanation and understanding as to why her personality seems rather unstable, and why she acts so brutally towards other people. On the other hand, we don’t really know anything about Alison’s past, so we assume she is just a nasty sly character and though her crimes are not as dire as Abigail’s, we do not really have the evidence to feel as much sympathy for her behaviour. Though I think we can like Alison to some extent, as even though we condemn her behaviour, the men in her story are not as admirable as John Proctor so maybe her behaviour does not seem so bad. She even has the advantage of being secure in a marriage, unlike Abigail who is an unmarried orphan living with her uncle. The presentation of Abigail in The Crucible is rather dark and frightening, a good example of this being at the court scene, where she is deliberately causing hysteria by throwing around accusations of witchcraft, and even going as far as pretending to be bewitched by Mary, and getting all the other girls to make believe the very same thing and repeat Abigail’s exact chants and actions.

1000 word justification of an assessment event implemented in the Essay

1000 word justification of an assessment event implemented in the workplace - Essay Example Rowntree (1987) stated that the purpose of an â€Å"assessment involves selection-formative or summative, maintaining standards-continuity of care and delivery, motivation of students-encouraging learning by questioning and quizzing. Feedback to students-performance can be a means of helping them learn and preparation of life-to utilize in future needs†. A comprehensive assessment consists of a formative and a summative assessment. Formative assessment refers to the process of ascertaining the student’s progress during a period of study (Welsh & Swann 2002). This was accomplished by asking the student to summarise the practical steps for clarification, and determining understanding of the task. This allowed the student to use social learning (Banura 1977 cited in Quinn 1997) and apply previous knowledge to successfully complete the task. Doing this it allowed the student to practice without the stress of being formally graded (Welsh & Swann 2002). Also, a formative assessment allows the student to obtain feedback on their performance and progress, which could be used in the summative assessment. Giving feedback can reinforce positive and negative elements of performance. It is vital to give feedback as soon as possible after the event. Feedback should also be given fairly promptly if it is to affect the student’s performance and ability to complete the skill safely. Feedback is essential because it gives the student the opportunity to ask questions and participate in discussions. Feedback supports the student’s acquisition of the task at hand. The assessment that the student participated in had to cover the set criteria listed in presentation provided by the mentor (Appendix 1). The desired outcome would be that the student demonstrated safe performance of newly acquired skills, knowledge and attitudes. The goal of the assessment focused on integrating theory into practice. Testing the student’s grasp of theory and

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Falling Head Permeability Test - Lab Report Example In the falling head test, the standpipe provides both the head of water and a means of measurement of the quantity of water flowing through the sample. The sample is connected to the standpipe whose diameter is most suited for it. The falling head principle is applied to the undisturbed sample that is in a sampling tube. The Falling Head Permeability test is done on soils whose permeability is less than 10-4 m/s. The coefficient of permeability, k, is the rate of discharge of a liquid and is directly proportional to the hydraulic gradient, i, and the cross-sectional area, a, of the sample (Mabrouk). The coefficient of permeability of the soil sample tested is k1= 5.41Ãâ€"10-5 m/s k2= 6.18Ãâ€"10-5 m/s. the mean Kmean = 5.795Ãâ€"10-5m/s. Based on the classification highlighted in step 9 of the experimental procedures, the soil sample can be defined to be of low permeability. Hence, the sample, which contains intermediate sized particles of and holds moistures, can be interpreted to be a silt clay. From these results, the general experiment of determining the coefficient of permeability of a soil sample can be described. Furthermore, the relationship between the coefficient of permeability and the pore size of the fine-grained soils has been established (Chiasson). This test was conducted for a single primary reason: to calculate the permeability of samples using the falling head permeability test. This test, which was conducted according to the laid down procedure found the coefficient of permeability to be valid.

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Schopenhaeur - Term Paper Example Many people have tried to explain this and there are many different religions which have been formulated on this basis. Many religions have different viewpoints on death however; Buddhism is one of the best in describing life after death. This paper will focus on the perspective utilized by Schopenheur. My friend life is something which we are given unknowingly and there is no knowledge from where we come from hence making us existence in the absence of our knowledge and will. This makes us mere existing objects who are unaware of our origins before birth and where would go after death. Since every person came onto the world without any worry of the future he or she has no reason or substantial basis to worry about the afterlife. Therefore my friend, as you age you can only enjoy and reminisce on the moments which you have lived as these are the ones which have had control over and were able to witness and acknowledge. These are the moments which were yours and you had control as well as the desire to make. There is no reason for you to think what will happen as you move to the next stage of life because you have already experience the most fulfilling part. There are many things which we do not know and if they are not in our hands then there is no reason which we should stress over them. If there is another phase of life after we die, then there are many ways which we can attempt to understand this phase. Yes my friend, curiosity is perhaps something that is existent in all of us; however, this is not to say you should be worried. In the past, many people, particularly religions have attempted to explain the afterlife and this makes it a very interesting subject. What you choose to believe of course entirely up to you. For example, Christianity has attempted to explain the afterlife from the viewpoint of eternal life. This is one aspect which is very controversial as there is a

American Revolution Essay Example | Topics and Well Written Essays - 500 words - 3

American Revolution - Essay Example The revolution took place as a result of accumulated grievances which the American people had had enough of. They were also protesting against the various acts that had been established by England and which were to their disadvantage. An example was the Stamp Act of 1765 which imposed that every American was to pay taxes to England in order to offset the costs of running the British Military Organization. There was the currency act of 1764 that prohibited issuance of legal tender money and this threated to destabilize the industrial economy. The quartering act of 1765 also contributed to the revolution as it required colonialists to house troops from Britain and even supply them with their hard earned food. The conflict that occurred between England and the colonies was basically brought about by the colonies disagreements with the rules introduced to them by their British leaders. These rules undermined them further and prevented them from being independent and they were tired and angry about this. They therefore started with revolts in some of the colonies which were ultimately copied and repeated in the rest of the colonies and this in turn led to the revolution which took place over a number of years. They were totally opposed to these policies and they started uniting against the British colonialists as they knew that once unite, they could easily get their independence. The colonies also stopped providing money to the British government. The British government had used up most of its resources and even accumulated debt from the war and they needed money from the colonies to recover which was not forthcoming (Morton 41). They started rioting and mass protests to refuse the new policies England was imparting on them hence giving a hard time to the colonialists. The point of no return was reached in 1763 after the seven year’s war. At this juncture, enough was enough with the oppression and the numerous Acts and

Universal healthcare the only answer Essay Example | Topics and Well Written Essays - 1500 words

Universal healthcare the only answer - Essay Example Healthcare is a human right, also in the Constitution under life liberty and the pursuit of happiness, but many Americans do not feel its benefits. Universal healthcare is the only answer because it will also save money. â€Å"We can eliminate wasteful inefficiencies such as duplicate paper work, claim approval, insurance submission, etc. We can develop a centralized national database which makes diagnosis and treatment easier for doctors† (Universal, 2009). There are many reasons to support universal healthcare supported by community health principles. Universal healthcare is about representing a true community healthcare principle of access for all, not just for all who can afford it. In terms of base arguments, supporters of national healthcare tend to argue that there should be a single-payer system in which healthcare is financed by the government but the government does not take control of the system in a way that diminishes privatized options. But on the other hand, â€Å"The current crisis in the U.S. healthcare system may be more one of perception than fact. While it is true that in certain areas of the country and for some segments of the population there are real healthcare access and coverage problems, coverage is available in most places and for most individuals. The magnitude of the crisis may not be significant enough to justify the major changes in the healthcare delivery system that will result from present reform proposals† (Kalkhof, 1994). It is the recommendation of this report that the current system of managed care observed at modern healthcare facilities should be changed from a consumer-based platform to a patient-based platform in which there is universal coverage and a renewed attention to upholding patient rights. â€Å"According to principles of American paternalism, no American should go without food and water, shelter, clothing, sanitary facilities, protection, physically and legal, equal opportunity,

CASE SCENARIO Essay Example | Topics and Well Written Essays - 500 words

CASE SCENARIO - Essay Example But there is no evidence of any spill. Situation Analysis And Solution: Let’s us assume that the production employee does not know how to identify the material, as the Hazard Communication Standard requires that all chemicals be appropriately labeled. â€Å"Under the provisions of the Hazard Communication Standard, employers are responsible for informing employees of the hazards and the identities of workplace chemicals to which they are exposed†, says OSHA in its information booklet. The emergency response team and the plant manager have already been informed about the incident. Entry to the area restricted except for those involved in the clean up operations. The first step to entering the area of incident involves wearing protective gears such Positive Pressure Self-Contained Breathing Apparatus, gloves and shoe covers by the team coordinators. A quick survey of the area is done and it declared as restricted area.Next is to identify the material that is spilled by identifying the label. Identifying the s pill is half work done, as this is will tell what procedure it needs to undertake to limit the hazardous situation. The HazMat Team is then given relevant spill response instructions. The following will be the action list they would follow: The team members also needed to be appropriately protected with the personal protective clothing and equipment. Restrict entry of any unauthorized individuals. As the spillage is from a 55 gallon drum, two or three team members will take care of transferring the contents into a larger drum as soon as possible. Two or three of the members work on limiting the spill from spreading further. A part of the hazard management team involves in relocating the other hazardous chemical containers to safer areas. As fumes are being produced, let us assume that the chemical that spilt was a strong acid. The next step is use

Helping Students Find a Purpose for Their Education Essay Example for Free

Helping Students Find a Purpose for Their Education Essay It has been my observation that many of my best students became intrinsically motivated to put more effort into their education after they have decided on a career purpose. A work or career purpose or mission answers the following question: How do I want my career to benefit others? It is also important to identify who (the population) we want to benefit. An example of a work purpose statement is, â€Å"I want to help those who are sick or injured to heal and rehabilitate. † This statement does not contain a career title, but it provides guidance for exploring a variety of careers that can fulfill this purpose. For example a student with this purpose could explore a variety of careers such as nurse, doctor, physical therapist, nutritionist, athletic trainer, fitness trainer, engineer or inventor of products for persons with disabilities, etc. The career that they choose will depend on their capability and willingness to acquire the necessary skills, education, training and credentials. Ideally the career choice will be one that uses their best talents and is one they will enjoy doing. Do you ever share with students why you chose to work in the field of education? Students need to learn about different careers from adults who work in different career fields and to hear what motivated them to make their career choices. I teach college success courses and I used to wait until the end of my courses to get into career development, exploration and planning. Students did not think about a career purpose until the last week or two of my courses. Recently I started covering these ideas in the second week of my courses so that students would have a clear direction for their education much sooner. Having a career purpose can make their education relevant and is likely to generate the intrinsic motivation to study and learn. Students need to be provided with opportunities for career guidance from counselors, teachers and professors in high school and college. You do not need to be teaching college or career success courses to do this, but can weave in a few questions and ideas into other courses. Here are a few questions you can ask your students so that they can begin a process of self-reflection about their career purpose: 1. What purpose do you want to accomplish in your career? 2. What benefits do you want others to receive as a result of the work you do? 3. What specific populations of people do you want to help? 4. How do you want to contribute and make a positive difference for others? 5. If you were wealthy and chose to work what would you do? 6. What problem or need in the world would you most like to fill or solve? 7. If you knew you could not fail what type of work would you do? 8. What are some natural talents you would like to develop and use in a career to fulfill your work purpose? When we expect students who lack self-knowledge and a work purpose to choose a major and career, we are putting the cart before the horse. Identifying a purpose first will guide students into best career choices. If we help students to determine an appropriate career goal then they will also have a purpose for pursuing a good education

The movie Cromwell Essay Example for Free

The movie Cromwell Essay As the movie Cromwell so clearly indicates, the struggle between King Charles I and Parliament was an important one for the development of British government and government all over the world. The two sides came to a fork in a proverbial philosophical road and they could not overcome differences in those opinions. On one hand, King Charles I was looking to protect what he thought was a mandate from God to act how he wished as the King of England. The members of English Parliament were looking to protect not only their own interests, but the interests of the people of England in not allowing one person to gain absolute control of the country. King Charles operated primarily under the assumption that people would respect the manifesto of â€Å"Divine Right of Kings†. In his own mind, Charles was appointed to the throne by God and because of that, he had not only the right, but the mandate to do whatever he pleased. Along his line of thinking, King Charles had a responsibility to do God’s work while he occupied the top seat of the English monarchy. The King’s entire tenure in control was marred by the fact that he did whatever he wanted without first consulting the powers that existed in Parliament. He levied taxes against the people of the country without the approval of Parliament. That was outdone only by the fact that he married a Roman Catholic woman and took other actions which brought the vaunted Church of England dangerously close to their former roots of Catholicism. In doing this, he not only threatened the power of the men in Parliament, but he also threatened the sanctity of the nation, which so many parties had worked very hard to protect. Parliament helped to push the action to the point where a war was absolutely necessary. They were prominent members of English society that had to work very hard to get to where they were in the government. Though power was certainly not the only thing that concerned these men, it was definitely one of their primary concerns through the entire struggle. They did not want to give even an inch to the King; for fear that he might take that inch and run with it. That particular Parliament had seen what could happen when a King had complete control and they were not about to let it happen again without a fight. In addition, they wanted to protect the country’s economic system, which struggled for much of the reign of King Charles I. The power struggle between these two sides is one of the many historical events that has had a significant impact on how the American government works. When the forefathers of the United States took the time to frame the constitution, they took measures to create a balance of power. As a direct result of King Charles and the situation with Parliament, the American founding fathers were sure to put a system of checks and balances into the core of the country’s values. That was to make sure that no one party, be it the President, the courts, or Congress, could not have complete power and control over the country. The realized that when a leader tried to use religion to justify his actions, it made stopping such a mandate extremely difficult for both the commoners of the country and the people who also held control.

Effects of Material on Braking Abilities

Effects of Material on Braking Abilities Abstract: The most important utility in our lives as of today is automobiles, there is a lot of research and development is going in every section of the automobile field to give the safest possible vehicle to the world. One such is Brakes section; this is very important part in every vehicle, though we have most accurate and efficient brakes now-a-days, but they fail at the extreme conditions of heat , vibrations , high frequencies etc., this project is mainly concentrated on the aspects which are causing adverse affect to fail and create unusual   disturbances in the brakes. One such is brake squeal, an unwanted sound which is caused due to the vibration of the brake pads against the disc generating the high pitch noise. There are few other problems which leads into the high frequency problems, vibrations, tear in the brake disc etc. Here in this project a detailed study of disc brake is taken into account by considering with two different materials cast iron and aluminium alloy. The performance of brake is studies using normal stress analysis, vibration analysis and thermal analysis. The main problem of squeal can be due to the combination of vibration in brake set-up from callipers to the brake discs. And can also due to the uneven surfaces of the brake disc which causes due to the improper heat dissipation in the brake disc, all this problems are kept into consideration and this analysis are carried out for brake disc with two different materials as mentioned. A simple change in the design of brake disc has also been done for the maximum heat dissipation and this design also studied in this extreme conditions. And these two type brake disc are compared in all its possibly calculated attributes and the best one is concluded. Introduction: An automobile is a creation of history when they started and now it has become a crucial part of the world. Automobile is a wheeled motor vehicle used for transporting passengers, good etc. There has been a lot of improvement in the automotive field in all ways from the past few decades. The main aim of the automotive department is to provide safest vehicle from its design to the material used for each component. Every single thing is decided on basis of the effect of it on the human lives. The vehicles we use are very efficient when compared with older generation vehicles, the safety increases with the development and technology. But there are few problems which are yet to be solved. One such is about brakes, as we know BRAKES are the most important part in the every moving body, we have seen very drastic improvement in the methods of braking system. In olden days the brakes were handled by hand and now we have disc brakes and hydraulic brakes.   But the whole concept of brakes is working on same principle of kinetic energy is converted into heat energy. We find brakes very commonly used in cars, bikes, aeroplanes, automated machines etc. Brake is a device which decelerates the vehicle or machine by converting its kinetic energy into other form of energy, which will bring the vehicle down to the rest. We have disc brakes now which require very less amount of effort and time to stop the vehicle due to its accuracy and sensitivity; this are widely used in vehicles now-a-days. The drum brakes were used for very long time and we use even now, these were also very efficient brakes but due to the very common issues of changing the brake pads very often due to the short hand braking or improper usage, this has been replaced by disc or hydraulic in few machines. But we have found very common issues in disc brakes due to the brake rotor and brake pads. Due to the high friction while short braking we get unwanted noise brake squeal, though it doesnt have much effect on the performance of the vehicle, but it may fail the brake due to the tear o f brake disc or brake pads. A detailed study of each problem will be studied in further report taking disc brake system. History of Brakes: Invention of brake has started with the automated machines; brakes came into light mainly when the motorised wheeled vehicles came into existence. Brakes were not only used in the vehicles, these are used in other machines as brake lever to stop the motion rotor and so on. It has been an essential part of the moving systems. Brakes have developed a lot from first generation vehicles to present time. Early braking systems used steel rimmed wheels to stop the vehicle, which consists of curved wooden block designed to bear against the steel tire when operated by a single leverage system from the driver seat. But the brake shoe used was normal way of braking either in the horse drawn vehicle or steam locomotive. In 1895 Michelin Brothers move a step ahead to replace the steel rimmed wheels with the pneumatic rubber tire to come out with a new braking system as the brake shoes were no longer satisfactory.   A new method of braking system was required in those times as two early devices attempted to apply the friction force to the axle or to drum on axle or transmission shaft were not efficient as wanted. One method was use of wooden block inside a flexible contracting metal band which when pressed together would tighten the drum causing friction between the drum, which is connected to the wooden block and w heel, then the vehicle gets slow down. The other method was inner wheel or brake drum which will add an external contracting band to bear against the drum to bring the vehicle to rest. In 1899 Daimler started cable operated braking system; a cable was wound around a drum and attached to the chassis, so that when the cable is tightened when car was moving forward, the rotation of drum will increase the tightness and grip of cable, so that it will reduce the amount of force required to pull the cable-lever on the pedal to stop the moving vehicle. This brake system worked well but still the braking efficiency was less, the added efficiency called servo assistance is still an important factor in drum brakes even today. The external brake was vulnerable to the atmospheric conditions like weathering and to un-even roads which caused a rapid loss of efficiency and wear of the brake shoe lining and on few times automatic brake use to happen due to the drum expansion. To overcome all these problems an internal shoe brake was developed were the expanding the brake shoes were placed the inside the brake drum, mainly to protect from the dust and weather. Originally early brakes were operated by mechanically, i.e. the transformation by mechanical system was used to expand the brake shoes against drum by the drivers effort applied on the brake pedal. It works by pressing the brake pedal, which make cam to rotate by a lever connected to pedal, which forces the shoes to come on contact with the brake drum. And springs attached to both of the brake shoes to retain the original position when brakes are released. As the early brakes use to operate on lever supported cables and linkage system of fixed rods, equalising the same amount of brake pressure on the wheels has presented many problems , which were solved when hydraulic system was introduced, which used fluid to transfer the force applied to the brake pedal. In hydraulic braking system the set-up of cylinders and pipe lines forms a closed system which is filled with fluid. The pressure generated in master cylinder will transmit equal force to the each wheel cylinder and then equal pressure is applied to all brake shoes. This hydraulic system is used with the disc brake as well. Disc brake is more efficient braking system which was used mostly sports car when introduced but now it has been a very common system in passenger vehicles. It has a disc and a calliper is attached to it which can be operated mechanically, hydraulically, pneumatically, electromagnetically. Types of brakes: The brakes are broadly explained as using friction, pumping or electromagnetism. But one brake system can also use more than one principle. As the project is based on the disc brake we will look forward only to discuss about the frictional brake. Frictional brakes: These types of brakes are mostly rotating devices with a stationary pad attached with a rotating surface. These types of brakes are widely used even now in modern automotive braking system. Basically this are developed from band brakes to drum brakes then to the disc brakes. Band brakes: A simple type of brake, works on a principle that a band is wrapped round the rotating drum. When a force is applied on the lever, the restraining torque is found from the difference in tension between the two ends of the belt. The principle of operation of the band brake is same as for belt drives. This is external type braking system, as we see in picture the brake shoe are mounted on the drum. Ref: http://school.mech.uwa.edu.au/~dwright/DANotes/brakes/intro/intro.html Drum shoe brakes: This type of brake usually mean the brake shoe is mounted to press the inside surface of the drum. Two brake shoes are connected with a calliper set-up; it has lining on it which will create a frictional force when pressed towards the moving surface of the vehicle. These types of drum brakes are still used in modern cars due to the some cost and engineering benefits. These are applied to the rear wheels of today cars. Ref: http://school.mech.uwa.edu.au/~dwright/DANotes/brakes/intro/intro.html Disc Brake: these most widely used brake of these days, A disc is mounted on the wheel or axle and brake pads are placed within the jaws of the calliper, this is give the necessary friction when it will grip on the brake disc. Ref: http://static.howstuffworks.com/gif/disc-brake3.jpg Characteristics of brakes: Brakes are described on basis of several characteristics as Peak force: The maximum force obtained to decelerate the vehicle is called peak force. Few times this can be more than the traction limit of tires, then the wheel gets skid Continuous Power dissipation: As we know that the brakes get hot in use and get fail when the temperature gets too high, the maximum amount of power that dissipates through the brake without failure is the continuous power dissipation. Fade: Due to the over heat of the brakes the surface of the brake pads or disc get fade which will cause decrease in the effectiveness of brakes. Few times even cooling will have big effect on to fade. Power: when a very less force leads to the braking force, which is higher than the other brakes in similar class then its stated as powerful brake, which is due to the sensitivity of the brake system. Durability: Friction brakes have the lining which has wear surfaces, these to be renewed periodically.   Like brake shoes, pads or brake disc. Even if wear surface due to brake shoe generates high peak force this will lead to wear quickly. Weight: In some circumstances brakes are often mounted on wheels, this can disturb the traction significantly. Here weight means brake itself or an additional support structure Noise: generally brakes create some minor noise when applied, but sometimes create a high pitch noise called squeal or grinding noise. Principles of braking system: Brakes work on simple principle to slow down the moving vehicle by applying an external force, it may use more than one component; directly or indirectly several components effect on the momentum of the moving vehicle. Various types of process are used for braking effect. Frictional brakes are most commonly used these days, these works on the simple mechanism of changing the kinetic energy into the heat energy, which is done by only factor friction. Friction is created when a stationary brake pad grips on the moving brake disc with a force applied. This type of braking system is also used in the disc brakes; the stationary brake pads rub on the disc rotor which moves relatively in its own axis. Basic laws of braking system: Braking system can be explained by two simple Newton laws; which will explain the whole concept of the braking system As we know that the Newtons second law The net force on an object is equal to the its mass times its acceleration and points in the direction of the acceleration F = m* a The law is used to find out the net force required by brake pads to bring the moving vehicle to rest, tough there are many other factors to be considered for calculation of brake force which will be discussed further. It can also be explained through Newton first law Every object remains at rest or in motion in a straight line at constant speed unless it is forced to change its state by an external force if we check this law, an external force (brake force) is required to change the state of the vehicle (motion to rest). As this law explained the evaluation of the brake force and system of braking, a further law explains how the brake force will stop the vehicle. Law of thermodynamics: Energy can neither be created nor be destroyed; it will be converted from one form of energy to other form. This explained the frictional force (brake force) is converted into the heat energy. Factors considered while Braking: There are many factors to be considered for the high braking efficiency and performance; here we will see the few important factors which have a more effect on braking efficiency. 1. Condition of disc rotor: An uneven disc or ruffed disc rotor will decrease the braking effect; it has to be very well maintained as few a times due to dust and weather a extra layer is formed on the disc surface which will have a negative effect on the braking concept. Or wear of disc rotor due to overheat. 2. Pressure on brake rotor: A sufficient amount of brake pressure is to be maintained to get enough frictional force to stop the vehicle. If less pressure is applied it will directly affect the brake efficiency as force acting on the two rubbing surface will become less. 3. Contact surface: The area of contact between the brake pads and disc rotor should be more then the high friction is obtained. If lining of brake pads or surface of disc rotor is uneven then area of contact will be less, which will affect the brake efficiency. 4. Tyres: The design of tyre also have a normal affect on the brake efficiency, the more the contact of tyre to the road surface the good will be the braking system. Worn tyres will have less braking action and will not allow vehicle to stop the required point and may also skid, braking action is found high in new tyres due to its more contact with the road surface. There are other factors which also play an crucial part in brake efficiency like aerodynamics, heat dissipation, weight of body etc., Causes of failure: The most commonly found causes for the brake failure are 1. Oil or grease on the brakes will cause failure as it interferes with the friction. If we found oil in brakes mean the oil seal has failed and is why oil is leaking. 2. Overheat of brakes to great degree, which will develop a hot spot on the rotor and drums. This spots will resist the friction from brake shoe and pads, therefore braking power is lost and brake fails. 3. Brake squeal which indicates the tear in the brake pads, by the time the brakes start making a grinding sound, they would have worn out past the pads to rotors. This will require to change more than just brake pads for new one, which will increase replacement cost as well. 4. Improper wheel alignment or disturbance in the steering system will also lead into the failure of brakes. Even if the mass of vehicle will get out of its range due to extra load will cause a brake failure due to the uneven load distribution. DISC BRAKE Introduction: Disc brakes came into existence in 1890s in England. But due to the poor state of roads and dusty conditions the disc and pads use to get rust and get wear, so the system got non-viable at that time. But later it was fully adopted in 1950s with new innovations in the previous design. Many companies started using it in their cars as it was better when to compared with drum brakes, the main reason as it has overcome the brake fade problem by providing the resistance to the brake components and overall performance is better when compared with drum brakes.   Disc brakes become popular in sports cars due to its braking performance. Now it has been common in commercial vehicles as well, as its used at front of the vehicles, as the front brakes perform most of the braking effort. Components: A disc brake assembly consists of a 1. Cast-iron disc (disc rotor) that rotates with the wheel. 2. Calliper assembly attached to the steering knuckle (operated mechanically or hydraulically). 3. Friction materials (disc pads) that are mounted to the calliper assembly. Operation: (Hydraulically powered) Disc brakes prove to be efficient when compared with drum brakes even the working principle is same for both systems. The basic principle of braking system The kinetic energy is converted into heat energy   When brake pedal is pressed, the hydraulic pressure is applied on the piston; it pushes the brake pad to get in contact with the disc. As the pressure increases the calliper pushes the outside pad to get in contact with the disc. Due the friction generated between pads and disc will create the braking force as the pads gets in contact fully with the disc rotor. But if we study the disc brakes widely, it shows that it does not use the much of the friction between the lining and rotor to increase the braking power as drum brakes does, they likely cause a pull between them. Disc brakes have constrained self-energizing action, there has to be sufficient hydraulic pressure to get the required braking force. The braking force can be increased by changing the size of calliper piston. Even less heat dissipation occurs as the friction surface is exposed to the air, which also reduces the braking fade.   Design of disc rotor: generally disc rotors are either solid or ventilated. The ventilated type disc rotor has cooling fins in the middle of the disc to ensure good cooling. Proper cooling ensures longer pad life and it also prevents fading. Some ventilated rotors have spiral fins which allow more air flow and better cooling. These fins are mounted on side of the vehicle and directional. Spiral fins are used in the front of the vehicles as front brakes take most of the braking action as more heat generates. Ref: https://pontiworld.com.au Design of calliper: The calliper are used as floating calliper or fixed calliper design, and these are mounted on the axle or attached to the wheel. Floating calliper type: The calliper are used as floating calliper or fixed calliper design, and these are mounted on the axle or attached to the wheel. this type of calliper requires less parts than the other type and its also less in weight and economical. Based on requirement it consists of one or two pistons. The piston is either side of the calliper. Hydraulic pressure from the main cylinder is generated and the piston thus press the brake pad towards the disc, then instantly an equal hydraulic pressure is generated at the other side and right brake pad pushed towards disc rotor and vehicle stops due to the braking force. Fixed calliper type: The calliper are used as floating calliper or fixed calliper design, and these are mounted on the axle or attached to the wheel. This type of calliper design has piston on both sides of the calliper, which provides the equal force to each brake pad. These fixed calliper types can set-up either one or two pistons on each side. The two pistons can generate a more braking force and a compact design, as these absorb and dissipate more heat, due to its size and weight. This design is capable for greater number of hard stops of short brakes without the effect of brake fade. Materials used for component: The material used for disc rotor plays an important role in braking force. The material should be tuff enough to stand on high pressures and high friction forces. Generally cast iron is used for disc rotor commercially, but ceramic discs are used for high-performance vehicles and heavy automobiles. Recent study shows that aluminium alloys also do a great job as disc. Now we will discuss in detail about the commonly used materials cast iron and aluminium alloys. Cast iron: Grey cast iron alloy is used for the manufacturing of disc rotor; it has superior properties and various advantages over other materials, as it best suitable for manufacturing and machining when compared with other materials which lead to the graphite lubricating the cut and breaking the chips. It contains 2.5%-4% of carbon and greater than 2% of silicon.   This material has good wear resistance and galling which leads to self lubricating due to the graphite flakes. The graphite microstructure of grey cast iron allows less shrinkage. The silicon percentage in the grey cast iron makes the material corrosion resistance and increases its fluidity when casting which also makes material easy to weld. Compared with other alloys of the cast iron, grey cast iron has low tensile strength , the good point about this material is the shock and impact resistance is almost doesnt exist. Here we will see the properties of the grey cast iron for ASTM 60, Tensile strength 62.5 Kpsi Compressive strength 187.5 Kpsi Shear modulus of rupture 88.5 Kpsi Modulus of elasticity ( Tension ) 20.4 - 23.5 Mpsi Modulus of elasticity ( Torsion ) 7.8 - 8.5 Mpsi Endurance Limit 24.5 Kpsi Brinerll Hardness 302 H_b Specific heat 447 j/kg deg Ref: http://www.engineershandbook.com Characteristics of Grey cast iron: Wear resistance: Grey cast iron works as excellent resistance to sliding friction wear, it is widely used for manufacturing of sliding components, most of the automobile components are made up of this item, its all because of the low coefficient of friction, resistance to the galling it has which is due to the effect of graphite flakes . This will help the disc rotor to withstand for high friction forces. Thermal conductivity: The important merit of grey cast iron is its high thermal conductivity, due to its flake graphite structure, heat dissipates occurs in material with good rate. This will increase the cooling of the disc rotor Machinability: Due to the ferrite graphite structure, grey cast iron is simplest and easiest alloys for machining and casting. This will make easy to get the typical designs of the disc rotor with spiral and fins Damping capacity: Grey cast iron has high ability to absorb vibration energy and also damping vibrations, which is due to the high percentage of the graphite flakes it has in it. It also has great property to resist high frequency vibrations. This will help disc rotor Aluminium Alloys: Aluminium is the important alloy of aluminium alloys, were the other metals are copper, silicon and magnesium. It has less tensile strength and low melting pointing. It has good casting characteristics due to its great levels of silicon (4-13%) in it. It is widely used as disc rotor due to its corrosion resistance.   But this is quite expensive when compared with cast iron. Though is in light in weight, has good electrical and thermal conductivity. It does also can be recyclable. All these properties brought a change in many industries to change their traditional materials i.e., aluminium alloys. Characteristics of aluminium alloys: Light weight: The best part of this material is its light in weight, actually its one third of steel in weight, due to its specific weight of 2.7 g/cm3. The more the energy consumed by aluminium the high will be the load capacity of the vehicle.   This will decrease the vibrations and also increases the brake efficiency due to its light weight. Properties of the aluminium alloys: Density 2600-2800 kg/m3 Melting point 660 deg Elastic modulus 70-79 Gpa Poisson's ratio 0.33 Tensile Strength 230-570 Mpa Yield Strength 215-505 Mpa Percent Elongation 10-25% Thermal expansion coefficient 20.4 -25.0 10-6 /k Thermal conductivity: its used in most of the high conductivity line like power transmission, it has twice of the copper in the properties, and its a good conductor of heat and electricity. This will increase the heat dissipation of the disc rotor. Ductility and recyclability: Due to the lower density and melting point, the material is considered as ductile, this will help to the complicated design, as we need in the disc rotor with spiral fins and groves for the air dissipation. Recyclability is also one great factor of aluminium as it consumes only 5% of the energy to melt it, and it doesnt affect its original quality of aluminium. Corrosion resistance: This is the main factor which made it to select for disc rotor manufacturing. It has a natural property of corrosion resistant as it surfaces form an oxide coating on it. While using as disc rotor further surface treatments like lacquering and anodising are done to increase its resistance towards corrosion. Major problems with Disc Brakes: The disc rotor of Disc Brakes is more exposed to the air, due to which there are very frequent chances of getting damaged. Usually this damage of disc rotor is explained in four common ways warping, cracking, rusting and scarring. Few a times the damage takes the disc into the unsafe area then the new disc is replaced with damaged ones. But sometimes using simple machining and other process this damages can be overcome. As scratches or damage on disc rotor can be removed by removing the thin layer on the disc on lathe machine if after that the thickness of the disc falls in the safe dimensions for the braking force. Warping: This is caused due to the excessive heat of the friction area of the disc rotor, due to excessive shorthand braking, uneven cooling of disc may also causes warping. If braking pads get into contact of disc excessively this will lead to warping after certain times, this warping is most commonly found in the racing cars as brakes are used very frequently due to speed and used at high gear times. There are few methods which can avoid the warping, braking at lower gear which will help to reduce the braking load on the brakes, and less heat is generated. The more the braking load, the more the heat generated and more the chances of improper cooling to take place. Changing the disc design with more fins can few times avoids warping. Improper installation of disc rotor may also leads to the warping as only the overwhelmed disc will come in contact with the brake pads. Cracking: This is found mainly in the drilled disc. Cracking occurs mostly around the edges and holes of the disc, due to the uneven expansion in severe environments. As the uneven expansion take place and the braking load varies every time the brake is applied which will lead to the cracking. And in several situations the disc will fail and no possible repair can be done. Even cracking can be overcome by maintaining proper the cooling of the disc and proper heat dissipation. If cracking is become severe then there might be a chance to replace the disc rotor. Rusting: This is found in the vehicle which are not used for period of time, the regular use keeps the friction area clean, but when not in use the friction area and slots get rusted and it reduces the braking power, due to which the strength of the disc also falls down and at this conditions disc should replace with new one. Scarring: Scarring occurs if something hard gets in contact with the disc while moving, which forms a hard spot on the disc, which reduces the braking power and weakens the brake. Generally this happens when the brake pad service life come to end and still its attached to the brake set-up then the steel support of the brake pad get in contact with the disc which creates a hard scratch. These scratches will form black slots when a vehicle come in use, and reduces the structure strength. This can be avoided by regular checking of brake pads checking life of the friction layer, machining the disc to remove the layer on surface of disc which removes the scratches. There are few phenomenal problems which has been a challenging task in braking department like brake squeal, brake judder and brake dust. These problems can be dangerous when they get on excessively. Change of design, material, brake assembly setup all these have been checked extensively to find out the perfect solution for these problems, this project is undertaken based on this problems. Lets discuss in detail about these problems and what are the methods being simplified to overcome it. Brake Squeal: squeal mean noise, this brake noise is a vehicle system problem due to the regularity and severity. The noise generated is mainly because of brake and suspension components together. This is not considered as the main problem to the vehicle were performance is the initial objective, but its not so proper for the road use. This noise is mainly between the pad and disc during the braking. But squeal can also be combination of disc, calliper and brake pads. To avoid squeal under the braking condition is not so possible, if we are assuming brake to absorb very high energy inputs. Actually this brake squeal came into account when front wheel drive and metallic brakes arrived. These metallic pads are harder than asbestos counterparts, and thus more squeal is observed if there are more irregularities and roughness on the rotor surface or if you found looseness between the pads and callipers. Few types of calliper designs are more noisier, if the pads of this callipers are not fitted so tightly and the calliper itself move around when brakes are applied. The more the brakes play the more are the chances of noise. Fixing the squeal problems in wrong way can lead to the squeal more worse. Brake squeal also occurs due to vibration of brake pads towards the disc rotor when vehicle is moving at low speed, this may not affect the braking performance much but will lead to the replacement of brake pads, this is very common problem which most of the vehicles are facing now.   Lot of methods are used to reduce the level of noise,   simple methods like having chamfers to the linings, applying grease between the pads and calliper, adding the brake shim between   the brake back plate and brake pads etc., these may help in some way to reduce the noise. Ref: http://www.aa1car.com/library/bsqueal.htm While using the methods to reduce the brake noise, have to assume the vehicle suspension system which acts more on the braking system, but at the end the squeal is avoided by trial and error method. Although we see an efficient improvement in understanding the actual reason for the brake squeal, it has been difficult to solve it. It was easily verified through the design and study to overcome the squeal, but it was different case practically. The failure was mainly caused because of the dynamic behaviour of the braking system and due to the gap between braking components. The easiest way was using high temperature Effects of Material on Braking Abilities Effects of Material on Braking Abilities Abstract: The most important utility in our lives as of today is automobiles, there is a lot of research and development is going in every section of the automobile field to give the safest possible vehicle to the world. One such is Brakes section; this is very important part in every vehicle, though we have most accurate and efficient brakes now-a-days, but they fail at the extreme conditions of heat , vibrations , high frequencies etc., this project is mainly concentrated on the aspects which are causing adverse affect to fail and create unusual   disturbances in the brakes. One such is brake squeal, an unwanted sound which is caused due to the vibration of the brake pads against the disc generating the high pitch noise. There are few other problems which leads into the high frequency problems, vibrations, tear in the brake disc etc. Here in this project a detailed study of disc brake is taken into account by considering with two different materials cast iron and aluminium alloy. The performance of brake is studies using normal stress analysis, vibration analysis and thermal analysis. The main problem of squeal can be due to the combination of vibration in brake set-up from callipers to the brake discs. And can also due to the uneven surfaces of the brake disc which causes due to the improper heat dissipation in the brake disc, all this problems are kept into consideration and this analysis are carried out for brake disc with two different materials as mentioned. A simple change in the design of brake disc has also been done for the maximum heat dissipation and this design also studied in this extreme conditions. And these two type brake disc are compared in all its possibly calculated attributes and the best one is concluded. Introduction: An automobile is a creation of history when they started and now it has become a crucial part of the world. Automobile is a wheeled motor vehicle used for transporting passengers, good etc. There has been a lot of improvement in the automotive field in all ways from the past few decades. The main aim of the automotive department is to provide safest vehicle from its design to the material used for each component. Every single thing is decided on basis of the effect of it on the human lives. The vehicles we use are very efficient when compared with older generation vehicles, the safety increases with the development and technology. But there are few problems which are yet to be solved. One such is about brakes, as we know BRAKES are the most important part in the every moving body, we have seen very drastic improvement in the methods of braking system. In olden days the brakes were handled by hand and now we have disc brakes and hydraulic brakes.   But the whole concept of brakes is working on same principle of kinetic energy is converted into heat energy. We find brakes very commonly used in cars, bikes, aeroplanes, automated machines etc. Brake is a device which decelerates the vehicle or machine by converting its kinetic energy into other form of energy, which will bring the vehicle down to the rest. We have disc brakes now which require very less amount of effort and time to stop the vehicle due to its accuracy and sensitivity; this are widely used in vehicles now-a-days. The drum brakes were used for very long time and we use even now, these were also very efficient brakes but due to the very common issues of changing the brake pads very often due to the short hand braking or improper usage, this has been replaced by disc or hydraulic in few machines. But we have found very common issues in disc brakes due to the brake rotor and brake pads. Due to the high friction while short braking we get unwanted noise brake squeal, though it doesnt have much effect on the performance of the vehicle, but it may fail the brake due to the tear o f brake disc or brake pads. A detailed study of each problem will be studied in further report taking disc brake system. History of Brakes: Invention of brake has started with the automated machines; brakes came into light mainly when the motorised wheeled vehicles came into existence. Brakes were not only used in the vehicles, these are used in other machines as brake lever to stop the motion rotor and so on. It has been an essential part of the moving systems. Brakes have developed a lot from first generation vehicles to present time. Early braking systems used steel rimmed wheels to stop the vehicle, which consists of curved wooden block designed to bear against the steel tire when operated by a single leverage system from the driver seat. But the brake shoe used was normal way of braking either in the horse drawn vehicle or steam locomotive. In 1895 Michelin Brothers move a step ahead to replace the steel rimmed wheels with the pneumatic rubber tire to come out with a new braking system as the brake shoes were no longer satisfactory.   A new method of braking system was required in those times as two early devices attempted to apply the friction force to the axle or to drum on axle or transmission shaft were not efficient as wanted. One method was use of wooden block inside a flexible contracting metal band which when pressed together would tighten the drum causing friction between the drum, which is connected to the wooden block and w heel, then the vehicle gets slow down. The other method was inner wheel or brake drum which will add an external contracting band to bear against the drum to bring the vehicle to rest. In 1899 Daimler started cable operated braking system; a cable was wound around a drum and attached to the chassis, so that when the cable is tightened when car was moving forward, the rotation of drum will increase the tightness and grip of cable, so that it will reduce the amount of force required to pull the cable-lever on the pedal to stop the moving vehicle. This brake system worked well but still the braking efficiency was less, the added efficiency called servo assistance is still an important factor in drum brakes even today. The external brake was vulnerable to the atmospheric conditions like weathering and to un-even roads which caused a rapid loss of efficiency and wear of the brake shoe lining and on few times automatic brake use to happen due to the drum expansion. To overcome all these problems an internal shoe brake was developed were the expanding the brake shoes were placed the inside the brake drum, mainly to protect from the dust and weather. Originally early brakes were operated by mechanically, i.e. the transformation by mechanical system was used to expand the brake shoes against drum by the drivers effort applied on the brake pedal. It works by pressing the brake pedal, which make cam to rotate by a lever connected to pedal, which forces the shoes to come on contact with the brake drum. And springs attached to both of the brake shoes to retain the original position when brakes are released. As the early brakes use to operate on lever supported cables and linkage system of fixed rods, equalising the same amount of brake pressure on the wheels has presented many problems , which were solved when hydraulic system was introduced, which used fluid to transfer the force applied to the brake pedal. In hydraulic braking system the set-up of cylinders and pipe lines forms a closed system which is filled with fluid. The pressure generated in master cylinder will transmit equal force to the each wheel cylinder and then equal pressure is applied to all brake shoes. This hydraulic system is used with the disc brake as well. Disc brake is more efficient braking system which was used mostly sports car when introduced but now it has been a very common system in passenger vehicles. It has a disc and a calliper is attached to it which can be operated mechanically, hydraulically, pneumatically, electromagnetically. Types of brakes: The brakes are broadly explained as using friction, pumping or electromagnetism. But one brake system can also use more than one principle. As the project is based on the disc brake we will look forward only to discuss about the frictional brake. Frictional brakes: These types of brakes are mostly rotating devices with a stationary pad attached with a rotating surface. These types of brakes are widely used even now in modern automotive braking system. Basically this are developed from band brakes to drum brakes then to the disc brakes. Band brakes: A simple type of brake, works on a principle that a band is wrapped round the rotating drum. When a force is applied on the lever, the restraining torque is found from the difference in tension between the two ends of the belt. The principle of operation of the band brake is same as for belt drives. This is external type braking system, as we see in picture the brake shoe are mounted on the drum. Ref: http://school.mech.uwa.edu.au/~dwright/DANotes/brakes/intro/intro.html Drum shoe brakes: This type of brake usually mean the brake shoe is mounted to press the inside surface of the drum. Two brake shoes are connected with a calliper set-up; it has lining on it which will create a frictional force when pressed towards the moving surface of the vehicle. These types of drum brakes are still used in modern cars due to the some cost and engineering benefits. These are applied to the rear wheels of today cars. Ref: http://school.mech.uwa.edu.au/~dwright/DANotes/brakes/intro/intro.html Disc Brake: these most widely used brake of these days, A disc is mounted on the wheel or axle and brake pads are placed within the jaws of the calliper, this is give the necessary friction when it will grip on the brake disc. Ref: http://static.howstuffworks.com/gif/disc-brake3.jpg Characteristics of brakes: Brakes are described on basis of several characteristics as Peak force: The maximum force obtained to decelerate the vehicle is called peak force. Few times this can be more than the traction limit of tires, then the wheel gets skid Continuous Power dissipation: As we know that the brakes get hot in use and get fail when the temperature gets too high, the maximum amount of power that dissipates through the brake without failure is the continuous power dissipation. Fade: Due to the over heat of the brakes the surface of the brake pads or disc get fade which will cause decrease in the effectiveness of brakes. Few times even cooling will have big effect on to fade. Power: when a very less force leads to the braking force, which is higher than the other brakes in similar class then its stated as powerful brake, which is due to the sensitivity of the brake system. Durability: Friction brakes have the lining which has wear surfaces, these to be renewed periodically.   Like brake shoes, pads or brake disc. Even if wear surface due to brake shoe generates high peak force this will lead to wear quickly. Weight: In some circumstances brakes are often mounted on wheels, this can disturb the traction significantly. Here weight means brake itself or an additional support structure Noise: generally brakes create some minor noise when applied, but sometimes create a high pitch noise called squeal or grinding noise. Principles of braking system: Brakes work on simple principle to slow down the moving vehicle by applying an external force, it may use more than one component; directly or indirectly several components effect on the momentum of the moving vehicle. Various types of process are used for braking effect. Frictional brakes are most commonly used these days, these works on the simple mechanism of changing the kinetic energy into the heat energy, which is done by only factor friction. Friction is created when a stationary brake pad grips on the moving brake disc with a force applied. This type of braking system is also used in the disc brakes; the stationary brake pads rub on the disc rotor which moves relatively in its own axis. Basic laws of braking system: Braking system can be explained by two simple Newton laws; which will explain the whole concept of the braking system As we know that the Newtons second law The net force on an object is equal to the its mass times its acceleration and points in the direction of the acceleration F = m* a The law is used to find out the net force required by brake pads to bring the moving vehicle to rest, tough there are many other factors to be considered for calculation of brake force which will be discussed further. It can also be explained through Newton first law Every object remains at rest or in motion in a straight line at constant speed unless it is forced to change its state by an external force if we check this law, an external force (brake force) is required to change the state of the vehicle (motion to rest). As this law explained the evaluation of the brake force and system of braking, a further law explains how the brake force will stop the vehicle. Law of thermodynamics: Energy can neither be created nor be destroyed; it will be converted from one form of energy to other form. This explained the frictional force (brake force) is converted into the heat energy. Factors considered while Braking: There are many factors to be considered for the high braking efficiency and performance; here we will see the few important factors which have a more effect on braking efficiency. 1. Condition of disc rotor: An uneven disc or ruffed disc rotor will decrease the braking effect; it has to be very well maintained as few a times due to dust and weather a extra layer is formed on the disc surface which will have a negative effect on the braking concept. Or wear of disc rotor due to overheat. 2. Pressure on brake rotor: A sufficient amount of brake pressure is to be maintained to get enough frictional force to stop the vehicle. If less pressure is applied it will directly affect the brake efficiency as force acting on the two rubbing surface will become less. 3. Contact surface: The area of contact between the brake pads and disc rotor should be more then the high friction is obtained. If lining of brake pads or surface of disc rotor is uneven then area of contact will be less, which will affect the brake efficiency. 4. Tyres: The design of tyre also have a normal affect on the brake efficiency, the more the contact of tyre to the road surface the good will be the braking system. Worn tyres will have less braking action and will not allow vehicle to stop the required point and may also skid, braking action is found high in new tyres due to its more contact with the road surface. There are other factors which also play an crucial part in brake efficiency like aerodynamics, heat dissipation, weight of body etc., Causes of failure: The most commonly found causes for the brake failure are 1. Oil or grease on the brakes will cause failure as it interferes with the friction. If we found oil in brakes mean the oil seal has failed and is why oil is leaking. 2. Overheat of brakes to great degree, which will develop a hot spot on the rotor and drums. This spots will resist the friction from brake shoe and pads, therefore braking power is lost and brake fails. 3. Brake squeal which indicates the tear in the brake pads, by the time the brakes start making a grinding sound, they would have worn out past the pads to rotors. This will require to change more than just brake pads for new one, which will increase replacement cost as well. 4. Improper wheel alignment or disturbance in the steering system will also lead into the failure of brakes. Even if the mass of vehicle will get out of its range due to extra load will cause a brake failure due to the uneven load distribution. DISC BRAKE Introduction: Disc brakes came into existence in 1890s in England. But due to the poor state of roads and dusty conditions the disc and pads use to get rust and get wear, so the system got non-viable at that time. But later it was fully adopted in 1950s with new innovations in the previous design. Many companies started using it in their cars as it was better when to compared with drum brakes, the main reason as it has overcome the brake fade problem by providing the resistance to the brake components and overall performance is better when compared with drum brakes.   Disc brakes become popular in sports cars due to its braking performance. Now it has been common in commercial vehicles as well, as its used at front of the vehicles, as the front brakes perform most of the braking effort. Components: A disc brake assembly consists of a 1. Cast-iron disc (disc rotor) that rotates with the wheel. 2. Calliper assembly attached to the steering knuckle (operated mechanically or hydraulically). 3. Friction materials (disc pads) that are mounted to the calliper assembly. Operation: (Hydraulically powered) Disc brakes prove to be efficient when compared with drum brakes even the working principle is same for both systems. The basic principle of braking system The kinetic energy is converted into heat energy   When brake pedal is pressed, the hydraulic pressure is applied on the piston; it pushes the brake pad to get in contact with the disc. As the pressure increases the calliper pushes the outside pad to get in contact with the disc. Due the friction generated between pads and disc will create the braking force as the pads gets in contact fully with the disc rotor. But if we study the disc brakes widely, it shows that it does not use the much of the friction between the lining and rotor to increase the braking power as drum brakes does, they likely cause a pull between them. Disc brakes have constrained self-energizing action, there has to be sufficient hydraulic pressure to get the required braking force. The braking force can be increased by changing the size of calliper piston. Even less heat dissipation occurs as the friction surface is exposed to the air, which also reduces the braking fade.   Design of disc rotor: generally disc rotors are either solid or ventilated. The ventilated type disc rotor has cooling fins in the middle of the disc to ensure good cooling. Proper cooling ensures longer pad life and it also prevents fading. Some ventilated rotors have spiral fins which allow more air flow and better cooling. These fins are mounted on side of the vehicle and directional. Spiral fins are used in the front of the vehicles as front brakes take most of the braking action as more heat generates. Ref: https://pontiworld.com.au Design of calliper: The calliper are used as floating calliper or fixed calliper design, and these are mounted on the axle or attached to the wheel. Floating calliper type: The calliper are used as floating calliper or fixed calliper design, and these are mounted on the axle or attached to the wheel. this type of calliper requires less parts than the other type and its also less in weight and economical. Based on requirement it consists of one or two pistons. The piston is either side of the calliper. Hydraulic pressure from the main cylinder is generated and the piston thus press the brake pad towards the disc, then instantly an equal hydraulic pressure is generated at the other side and right brake pad pushed towards disc rotor and vehicle stops due to the braking force. Fixed calliper type: The calliper are used as floating calliper or fixed calliper design, and these are mounted on the axle or attached to the wheel. This type of calliper design has piston on both sides of the calliper, which provides the equal force to each brake pad. These fixed calliper types can set-up either one or two pistons on each side. The two pistons can generate a more braking force and a compact design, as these absorb and dissipate more heat, due to its size and weight. This design is capable for greater number of hard stops of short brakes without the effect of brake fade. Materials used for component: The material used for disc rotor plays an important role in braking force. The material should be tuff enough to stand on high pressures and high friction forces. Generally cast iron is used for disc rotor commercially, but ceramic discs are used for high-performance vehicles and heavy automobiles. Recent study shows that aluminium alloys also do a great job as disc. Now we will discuss in detail about the commonly used materials cast iron and aluminium alloys. Cast iron: Grey cast iron alloy is used for the manufacturing of disc rotor; it has superior properties and various advantages over other materials, as it best suitable for manufacturing and machining when compared with other materials which lead to the graphite lubricating the cut and breaking the chips. It contains 2.5%-4% of carbon and greater than 2% of silicon.   This material has good wear resistance and galling which leads to self lubricating due to the graphite flakes. The graphite microstructure of grey cast iron allows less shrinkage. The silicon percentage in the grey cast iron makes the material corrosion resistance and increases its fluidity when casting which also makes material easy to weld. Compared with other alloys of the cast iron, grey cast iron has low tensile strength , the good point about this material is the shock and impact resistance is almost doesnt exist. Here we will see the properties of the grey cast iron for ASTM 60, Tensile strength 62.5 Kpsi Compressive strength 187.5 Kpsi Shear modulus of rupture 88.5 Kpsi Modulus of elasticity ( Tension ) 20.4 - 23.5 Mpsi Modulus of elasticity ( Torsion ) 7.8 - 8.5 Mpsi Endurance Limit 24.5 Kpsi Brinerll Hardness 302 H_b Specific heat 447 j/kg deg Ref: http://www.engineershandbook.com Characteristics of Grey cast iron: Wear resistance: Grey cast iron works as excellent resistance to sliding friction wear, it is widely used for manufacturing of sliding components, most of the automobile components are made up of this item, its all because of the low coefficient of friction, resistance to the galling it has which is due to the effect of graphite flakes . This will help the disc rotor to withstand for high friction forces. Thermal conductivity: The important merit of grey cast iron is its high thermal conductivity, due to its flake graphite structure, heat dissipates occurs in material with good rate. This will increase the cooling of the disc rotor Machinability: Due to the ferrite graphite structure, grey cast iron is simplest and easiest alloys for machining and casting. This will make easy to get the typical designs of the disc rotor with spiral and fins Damping capacity: Grey cast iron has high ability to absorb vibration energy and also damping vibrations, which is due to the high percentage of the graphite flakes it has in it. It also has great property to resist high frequency vibrations. This will help disc rotor Aluminium Alloys: Aluminium is the important alloy of aluminium alloys, were the other metals are copper, silicon and magnesium. It has less tensile strength and low melting pointing. It has good casting characteristics due to its great levels of silicon (4-13%) in it. It is widely used as disc rotor due to its corrosion resistance.   But this is quite expensive when compared with cast iron. Though is in light in weight, has good electrical and thermal conductivity. It does also can be recyclable. All these properties brought a change in many industries to change their traditional materials i.e., aluminium alloys. Characteristics of aluminium alloys: Light weight: The best part of this material is its light in weight, actually its one third of steel in weight, due to its specific weight of 2.7 g/cm3. The more the energy consumed by aluminium the high will be the load capacity of the vehicle.   This will decrease the vibrations and also increases the brake efficiency due to its light weight. Properties of the aluminium alloys: Density 2600-2800 kg/m3 Melting point 660 deg Elastic modulus 70-79 Gpa Poisson's ratio 0.33 Tensile Strength 230-570 Mpa Yield Strength 215-505 Mpa Percent Elongation 10-25% Thermal expansion coefficient 20.4 -25.0 10-6 /k Thermal conductivity: its used in most of the high conductivity line like power transmission, it has twice of the copper in the properties, and its a good conductor of heat and electricity. This will increase the heat dissipation of the disc rotor. Ductility and recyclability: Due to the lower density and melting point, the material is considered as ductile, this will help to the complicated design, as we need in the disc rotor with spiral fins and groves for the air dissipation. Recyclability is also one great factor of aluminium as it consumes only 5% of the energy to melt it, and it doesnt affect its original quality of aluminium. Corrosion resistance: This is the main factor which made it to select for disc rotor manufacturing. It has a natural property of corrosion resistant as it surfaces form an oxide coating on it. While using as disc rotor further surface treatments like lacquering and anodising are done to increase its resistance towards corrosion. Major problems with Disc Brakes: The disc rotor of Disc Brakes is more exposed to the air, due to which there are very frequent chances of getting damaged. Usually this damage of disc rotor is explained in four common ways warping, cracking, rusting and scarring. Few a times the damage takes the disc into the unsafe area then the new disc is replaced with damaged ones. But sometimes using simple machining and other process this damages can be overcome. As scratches or damage on disc rotor can be removed by removing the thin layer on the disc on lathe machine if after that the thickness of the disc falls in the safe dimensions for the braking force. Warping: This is caused due to the excessive heat of the friction area of the disc rotor, due to excessive shorthand braking, uneven cooling of disc may also causes warping. If braking pads get into contact of disc excessively this will lead to warping after certain times, this warping is most commonly found in the racing cars as brakes are used very frequently due to speed and used at high gear times. There are few methods which can avoid the warping, braking at lower gear which will help to reduce the braking load on the brakes, and less heat is generated. The more the braking load, the more the heat generated and more the chances of improper cooling to take place. Changing the disc design with more fins can few times avoids warping. Improper installation of disc rotor may also leads to the warping as only the overwhelmed disc will come in contact with the brake pads. Cracking: This is found mainly in the drilled disc. Cracking occurs mostly around the edges and holes of the disc, due to the uneven expansion in severe environments. As the uneven expansion take place and the braking load varies every time the brake is applied which will lead to the cracking. And in several situations the disc will fail and no possible repair can be done. Even cracking can be overcome by maintaining proper the cooling of the disc and proper heat dissipation. If cracking is become severe then there might be a chance to replace the disc rotor. Rusting: This is found in the vehicle which are not used for period of time, the regular use keeps the friction area clean, but when not in use the friction area and slots get rusted and it reduces the braking power, due to which the strength of the disc also falls down and at this conditions disc should replace with new one. Scarring: Scarring occurs if something hard gets in contact with the disc while moving, which forms a hard spot on the disc, which reduces the braking power and weakens the brake. Generally this happens when the brake pad service life come to end and still its attached to the brake set-up then the steel support of the brake pad get in contact with the disc which creates a hard scratch. These scratches will form black slots when a vehicle come in use, and reduces the structure strength. This can be avoided by regular checking of brake pads checking life of the friction layer, machining the disc to remove the layer on surface of disc which removes the scratches. There are few phenomenal problems which has been a challenging task in braking department like brake squeal, brake judder and brake dust. These problems can be dangerous when they get on excessively. Change of design, material, brake assembly setup all these have been checked extensively to find out the perfect solution for these problems, this project is undertaken based on this problems. Lets discuss in detail about these problems and what are the methods being simplified to overcome it. Brake Squeal: squeal mean noise, this brake noise is a vehicle system problem due to the regularity and severity. The noise generated is mainly because of brake and suspension components together. This is not considered as the main problem to the vehicle were performance is the initial objective, but its not so proper for the road use. This noise is mainly between the pad and disc during the braking. But squeal can also be combination of disc, calliper and brake pads. To avoid squeal under the braking condition is not so possible, if we are assuming brake to absorb very high energy inputs. Actually this brake squeal came into account when front wheel drive and metallic brakes arrived. These metallic pads are harder than asbestos counterparts, and thus more squeal is observed if there are more irregularities and roughness on the rotor surface or if you found looseness between the pads and callipers. Few types of calliper designs are more noisier, if the pads of this callipers are not fitted so tightly and the calliper itself move around when brakes are applied. The more the brakes play the more are the chances of noise. Fixing the squeal problems in wrong way can lead to the squeal more worse. Brake squeal also occurs due to vibration of brake pads towards the disc rotor when vehicle is moving at low speed, this may not affect the braking performance much but will lead to the replacement of brake pads, this is very common problem which most of the vehicles are facing now.   Lot of methods are used to reduce the level of noise,   simple methods like having chamfers to the linings, applying grease between the pads and calliper, adding the brake shim between   the brake back plate and brake pads etc., these may help in some way to reduce the noise. Ref: http://www.aa1car.com/library/bsqueal.htm While using the methods to reduce the brake noise, have to assume the vehicle suspension system which acts more on the braking system, but at the end the squeal is avoided by trial and error method. Although we see an efficient improvement in understanding the actual reason for the brake squeal, it has been difficult to solve it. It was easily verified through the design and study to overcome the squeal, but it was different case practically. The failure was mainly caused because of the dynamic behaviour of the braking system and due to the gap between braking components. The easiest way was using high temperature