The Mall as Disney Coursework Example | Topics and Well Written Essays - 500 words

The Mall as Disney - Coursework Example Since Richards main concern is in Disneyland, Main Street is of much importance to him so that the people reading his essay can understand the whole history behind Disneyland Richard also uses Main Street because of its architectural similarities with Disneyland. This clearly shows that main street had a big role to play in the development of Disneyland. The past life of the American people shows by the architecture of Main Street. This same architecture also exists in Disneyland and this is the reason why Richard focuses a lot on Main Street. Main streets a generic street name, which in most parts of the world, used for socializing and retailing. USA Main Street has a lot of cultural impact on the lives of the American people. It is here that people came to shop for all their needs and at the same time sit down and socialize with others about what was going on in their lives. Main Street in the USA led to the development of several cities as more people came to these places to shop and socialize while providing enough recourse to the public to be able to come up with Disneyland. The architecture of Main Street also tells a lot about the culture of the American people. Every little building shows that the people were organized and that they valued art and architecture. The architectural configuration of Main Street gives us the impression of how the people loved buildings. The buildings perform different functions; some act as shopping malls. Each building has a place for socializing meaning that the people loved a lot of socializing. The other cultural role played by Main Street is the development of architecture in America. From Main Street, we are able to see how buildings look and how similar they are to Disneyland. We get to see how people built their houses, how they shopped and exact places where they socialized. Main Street also gives us the American culture of education. Many schools and colleges develop from

Online Billing System Essay Example for Free

Online Billing System Essay POS, Inventory System, Networking and Web Based System are one of the most useful systems for the company. Nowadays, because of our technologies it’s easy to transfer the different information in different branch of company with the help of our computers and also the system. Almost all businesses use a POS process. There are many reasons for this. Many businesses have multiple locations. POS can help to automate transactions and it can records all the sales in the organization or we can say it can use it to make transaction easier. Every employee can also see all the transaction that has been made. Inventory System can be used for transactional updates or it can view all the available stocks and display out of stock products or items. Inventory System can have many advantages and are suitable in availability and display the in and out of stocks products. Networking’s usually use to connect the POS and Inventory system to all branches of the CreamlineDairy Corporation. Web Based System has many advantages and is preferable in POS, inventory and networking particularly notifying your outstanding sale. The company have been encountering some problem in terms of no link depot and main plant. They want to connect to the other branch, or we can say they want to view their point of sale and inventory system to their entire branch. The purpose of our system is to let every branch of Creamline be updated to the transactions of sale by the help of networking. The develop system will be a great help to the employee but of course for the manager even if they are not in the organization. Creamline Dairy Corporation located at Unit 701 Prestige tower condominium, F. Ortigas Jr. Ave.(Fromely Emerald Ave.), Ortigas Center Pasig City 1605 Philippines.Creamline’s plant and head office is located at Bldg. 5210, C.M. Recto Highway, Clark FreeportZone, Pampangga.

Richard the Third as a Hero or a Villain :: Papers Richard III

A hero is a man who is distinguished by exceptional courage, nobility and strength to carry out tasks that are involving great risks. A hero can also be a person who fights for other people to help or save them from their fears. He opposes the villain- a person who does wicked or evil intentionally to harm others in some way, emotionally or physically. A character that is placed to do badly. He is always opposing the hero to overthrow the hero’s qualities to gain power from the other side to help him or his side. Villain: Richard is seen as a villain in some aspects because he kills anyone who stands in his way. Richard talks about a pretext for his villainy by pointing out his physical deformity. â€Å"Why, I in this weak piping time of peace. Have no delight to pass away the time unless to spy my shadow in the sun and descant on mine own deformity. And therefore since I cannot prove a lover to entertain these fair well-spoken days, I am determined to prove a villain and hate the idle pleasures of these days.† He says that since he was not made to be a lover, he has no use for peace, and will willingly destroy peace with his crimes. This contributes to a very villainous role. Richard begins his movement for the throne. He manipulates Lady Anne, into marrying him, even though she knows that he murdered her first husband. He has his own older brother, Clarence, executed, and shifts the burden of guilt onto his sick older brother King Edward. He is eager to get the throne and he kills an enormous amount of people to get there: King Edward. Court noblemen, Lord Hastings, kinsmen of Edward, Queen Elizabeth, the two young princes and Queen Anne. These people were killed because he needed to get the throne for his greed. Only a villain would commit these crimes for his greed. Richard is disloyal by betrayal of close family, friends and relatives.

THe Metamorphosis of MAlcolm X Essays -- Essays Papers

THe Metamorphosis of MAlcolm X Malcolm X once wrote, â€Å"My life has always been one of changes† (Haley 404). In his autobiography, The Autobiography of Malcolm X, it is very evident that through his life, he went through a series of drastic changes that went from one extreme to another. He went from being at â€Å"the bottom of the American white man’s society,† to become one of the most influential advocates of Black pride (150). Throughout the novel the most evident changes are when Malcolm X moves to Boston, goes to prison, and going on Hajj. After living in Michigan, Malcolm X moves in with his half-sister, Ella, in Boston. Malcolm X described the move as â€Å"pivotal or profound in its repercussions† (38). When he gets to Boston, he sets out to explore the city and to â€Å"get the feel of Boston† (40). When he looks around the area he is living in he finds it full of nothing but â€Å"Hill Negroes† (40). He notices that all these black people are simply breaking their â€Å"backs trying to imitate white people† (40). He immediately rejects their way of thinking and finds himself in the middle of the town’s â€Å"ghetto section† (42). Soon through his friendship with â€Å"Shorty†, Malcolm X is exposed to a new kind of living. He spends his first month in Roxbury with his â€Å"mouth hanging open† (48). He saw small black children â€Å"shooting craps, playing cards, fighting†¦ [throwing] around swear words and slang expressions† (43). Eventually, all this exposure to black people â€Å"being their natural selves† took a great toll on him (43). After hanging out with Shorty and his friends, inevitably, he took his first reefers, first cigarettes, and the first liquor he drank. He ultimately went from being â€Å"country† to a â€Å"cool cat.† When he was exposed to all these â€Å"jungle streets,† he became a hustler and soon began to live like an animal, living only to survive (163). As he became more involved with these people he lost all sense of values and morals. He eventually became a common street hustler, drug dealer, and burglar until he was finally caught and served seven years in jail. Malcolm X’s experience in jail â€Å"saved† him eventually and molded him into the great leader he is known for today. While in prison the first thing that made a â€Å"positive impression† on his life is a fellow inmate named â€Å"Bimbi.† (153). What impressed him the most... ...letion of the Hajj he accepted the true Islam. The â€Å"color-blindness of the Muslim world’s religious society and the color-blindness of the Muslim world’s human society† greatly influenced Malcolm X’s decision to convert to the true Islam, and take back all his beliefs that the white man on the whole was the devil. Rather, the â€Å"specific attitudes and actions toward the black man, and toward all other non-white men† that was condescending, was what was wrong with the American society (333). This trip made a great impact on Malcolm X’s beliefs and changed his life. A year after he returned, Malcolm X was shot repeatedly in the chest while giving a speech in front of two hundred people, including his wife and four children. His life was characterized by a number of extreme changes that transformed his views and what he stood for. When he moved to Boston he found himself at the bottom of the American society, when he went jail he found himself again and gained self-pride, but when he came back form Mecca, as El-Hajj Malik El-Shabazz, his views totally changed, he was on the top of the American society and there he will remain as one of the most influential advocates of Black pride.

In the stories of F. Scott Fitzgerald, everyone in the end experiences defeat. To what extent is this statement true? Essay

In â€Å"Flappers and Philosophers†, the ideas of defeat and humiliation are presented throughout the collection. The author produces a profound exploration into the lives of the female protagonists who depend on popularity and sexuality as sources of power. It also deals with the ramifications of being an outsider during that period of time and how defeat is nearly always the result from the need for acceptance into those societies. Although many of the characters suffer the negative consequences of their actions in their respective societies, some do achieve victory, but at a price. To understand the characters in the story we must first deal with the social, cultural and historical contexts. These short stories were written between the world wars and among the interwar boom, before the Great Depression. This era was very important of women, young people, the arts and creative industries. The blossoming of youth culture also contributed to the rise of â€Å"flapperdom†. Before this period, we had the Victorian era, where women were subjected to immense conservatism, and their emotions and opinions were unjustly oppressed. Women were expected to cover up and know their place in the social hierarchy. â€Å"Flapperdom† introduced the thought of independence and non-conformity. The epitome of this idea would be the character of Ardita in â€Å"The Offshore Pirate†. She is an allegory that represents a whole shift in the mode of behaviour, a kind of liberation into something that is more dangerous, alive and sexy. In many of the short stories the female protagonist does suffer from defeat as shown in the short story â€Å"The Ice Palace†. Sally Carrol is a Southern Belle, who wishes to become a flapper. She does not succeed in this matter, as she is forced to return to her home after a trial run in the North. The author has used two distinct sematic fields to suggest the binary opposition between the North and the South. The South is warm and bright, with â€Å"the sunlight dripp[ing] over the house light golden paint.† The central motif in the paragraph of the short story is liquid light and that gives the reader a feeling of warmth and laziness. The two worlds are juxtaposed when the author describes the setting of the North. The rigid nature of the lexical choice in part III of the story shows how Sally Carrol is a microcosm of the South transplanted into the hostile nature of the North. â€Å"It was very cold† and Sally Carrol â€Å"slid uncomfortably† into her clothes and she â€Å"stumbled† up to the diner. The semantic field of ice is used here as seen in the words â€Å"sliding† and â€Å"slippery†. This gives the reader the impression that Sally Carrol is very awkward in this setting and not in control as a flapper should be. Sally Carrol judges things by how long it has been around, not in terms of monetary value. The difference in value systems between the North and the South makes it impossible for Sally Carrol to integrate into the Northern society, a society fuelled by money. Therefore Sally Carrol has the hallucination of Margery Lee, who is a personification of the old South. Sally Carrol experiences defeat and cannot follow her dreams of living as a flapper because of the restrictions in her abilities to adapt to a new environment. However, one may look at it the other way and say she has actually succeeded in living the life she is most suitable for – the Southern life. This is evident in the lexical shift in part VI, where the surroundings are smothered in the â€Å"wealth of golden sunlight†. This parallels part I of the story provides a certain unity that enables the reader to feel like the Southern life is where Sally Carrol belongs. In â€Å"Bernice Bobs Her Hair†, Bernice deals with the problem of being an outsider to an elite society full of successful people. She is seduced into â€Å"flapperdom† by Warren, who initiated the process by flirting with her. The remark that she had an â€Å"awfully kissable mouth† made her excited enough to change into someone who is obsessed with superficiality. She becomes an artificial flapper, a shadow of Marjorie. The struggle for acceptance is evident through the fact that even though the ideas underpinning their belief system is from two different paradigms, Bernice still learns to grasp onto that vibrant and fleeting youth. Stripped from her original values, and seduced into the world of â€Å"flapperdom†, Bernice only superficially assimilates into the elite society but fails at the end when her bluff is called. However, through this defeat, one may argue that she has actually achieved more. Liberating herself from the shackles of the Victorian era, she started to exhibit the traits of a flapper when she cuts off Marjorie’s hair. Not only did this provide an intense climax to the short story, it also explains that although the character experiences defeat, the resultant victory can compensate for that. Although on the surface â€Å"The Cut-glass Bowl† is a story about an enormous glass punch bowl ruining the life of Eveyln Piper, when you look at it closely, the story traces the deterioration of her â€Å"flapperdom† and her marriage to a prosperous hardware dealer whose business declines over several years. The author foreshadows this deterioration at the beginning of the text when he says that â€Å"the struggle for existence began†. â€Å"The bonbon dish lost its little handle†; a â€Å"cat knocked the little bowl off the sideboard†; â€Å"the wine glasses succumbed to leg fractures†. Throughout the story, an idea of superficiality comes into play. The cut-glass bowl is a conceptual metaphor that not only embodies the character Evelyn, but also outlines the features of her marriage. It is â€Å"as hard as† she is and â€Å"as beautiful and as empty and as easy to see through.† Her marriage is empty as she has to see someone else other than her husband to relight her fire. Even her words contain nothing, as they are in italics suggesting a false and unnecessary emphasis. Evelyn lives in a society obsessed with external beauty and superficiality. The author finds it necessary to describe the â€Å"beautiful† Mrs Harold Piper with her â€Å"young, dark eyes†. Evelyn experiences defeat as she is married and no longer able to capture that fleeting youth and vibrant energy that formed the basis of her existence. She fails to retain her physical beauty in a society where it is valued the most. Again, towards the end, she gains a sense of victory when she destroys the cut-glass bowl that has destroyed her life. Even here, the author stresses how vulnerable and helpless Eveyln is as she struggles to smash the bowl. The lexical choice here is in the sematic field of difficulty and uneasiness. She had to â€Å"tighten her arms† and her muscles were â€Å"tauted†. Her energy was â€Å"desperate† and â€Å"frantic†, and her effort was â€Å"mighty† and â€Å"strained†. The author cleverly uses the juxtaposition of the size of the bowl with the size of Evelyn to accentuate the difficulty she experiences. Furthermore, the repetition of the phrase: â€Å"she must be quick – she must be strong† shows that although she does suffer defeat, victory and liberation can be achieved through great difficulty. In his short stories, F Scott Fitzgerald has made sure everyone at the end suffers some kind of defeat. This is achieved by Ardita in â€Å"The Offshore Pirate† being humiliated, Sally Carrol in â€Å"The Ice Palace† returning to her hometown, Bernice in â€Å"Bernice Bobs Her Hair† bobbing her hair, and Evelyn in â€Å"The Cut-glass Bowl† losing the essence that used to define her as a flapper. However, the author has also made us realise that in life, even though we may experience defeat and humiliation, we must look within ourselves and find that personal victory that will surpass the negative feelings of loss.

Business Essay Writing Guide Essays

Business Essay Writing Guide Essays Business Essay Writing Guide Paper Business Essay Writing Guide Paper The business essay related to the finance, investments or budgeting operates around the specific terminology, encompasses credible sources, adequate and faithful statistical representation, and clear and readable structure. The formal writing such as request or application forms to banks or credit unions uses the standardized structure with the clear introduction, the purpose of the paper, and necessary information that accurately supports the meaning of the essay. While the internal business communication can be simplified to the company’s cultural code and ethics, the business request or financial letter is using specific structure and vocabulary that makes them the gold standard in writing about money. The semi-formal managerial pieces about money may have more extended structure and organization that depend on the purpose and the outcome of such an article. Thereby, all these ‘money’ papers have several features in common so that these aspects can be used as a background for the financial report, business requests or topic-essays related to the money. Structure of the Paper Introduction Each paper should represent the aim or the purpose why it is written or what results do you expect to get. The introductory part should include the overall representation of the topic, whether it is the report, request, informative article or essay. Moreover, the introduction should encompass the reason why you are writing this piece so that the reader of your article will understand your motivation or why this essay is essential to read. The final part of the introduction is your thesis statement or request that will state your position during the whole paper or indicate the precise message of your writing. Body part The body part can be divided into various sections that will represent several ideas that should be included or delivered by the essay. While this aspect depends on the writers’ preferences, it is better to explain what some papers should consist of, based on their purposes. Examples of Money Papers’ Structure The financial request should include information about all the vital economic aspects that you want to discuss or present. The information should be supported by real-world evidence, clear statistical data, and references to the appropriate literature (other financial reports, legal acts or credible business documents), databases or commercial organizations. Moreover, the terminology of such writing should provide the writer’s in-depth understanding of the topic and excellent money management skills. Furthermore, the financial request should exclude any vagueness or biased language and operate only with information presented in the paper. In case some supportive documents are used they should be mentioned and appropriately cited to exclude plagiarism or misleading information. The business essay related to the finance or budgeting should consist, at least, of three paragraphs that represent the background of the proposal, analysis of the situation, and recommendations or the solution. If you want to write the paper related to money savings or about how to manage money, you should begin with the problem or issue introduction. The brief explanation about the problem or solution should include background information, main causes that insisted on writing the paper, and how the situation looks like for now. Then, the money essay should provide the analysis of the case, using some principals of money management, amount of money that should be used or saved, and people that may be involved or affected by the depicted problem or proposed solution. Besides, the last paragraph of the money essay’s body part should summarize the issue and provide the recommendation or resolution as the paper’s outcome. While this type of writing has extended purposes, the topic may vary from the improvement of poor money management to explain how to save money or place money in the bank. Another type of essays related to money is students’ requests for a student loan or some college incentives that are the important issue for the modern youth. This type of money management essay is essential for those who need not only to make a financial request but also to get an understanding of how to communicate in the real world. Besides, this type of writing requires in-depth preparations and double-check of the information that may be included in the paper. The money management essay related to the students’ loans or financial activities should encompass the specific and clear purpose, information about the writer, and the reason why you write this paper. Besides, the paper cannot operate with such terms, as a ‘lot of money,’ ‘manage money’ or ‘need money’ so that you should exclude them from your writing. Nonetheless, these phrases can be replaced by more appropriate information about the precise sum, the purpose for this money, and why the student will need these funds. Conclusion The conclusion of the essay related to money should be a brief reminder of the paper thesis and summary of all points mentioned in the paper. Besides, the document can include some references to the reader if the writing piece is the report or advisory article. Some Tips to Improve Money Essay Writing Skills The structure and organization of the money essay have no clear definition or standards as all depends on the purpose of the paper. Thereby if you required to write the article about your money or some aspects of money management and allocation, you should focus on your writing skills, language, and main ideas that you want to deliver. For instance, to request money, you should include the reasons and main fields where you will use them. This can be college, additional education, some personal activities or even mortgage. However, such paper does not require you to write about you or your preferences directly, as the caring message is obtaining the permission or grant. In case, the writing should discuss the financial status or some money-saving process; you should represent your excellence in money management and resources allocation. While this can be a tricky task, to avoid some traps, you should analyze the situation and possess your proposals from the reader’s perspective. If the topic of your essay is overspending and budgeting, include the information or techniques that may save money or mitigate some adverse issues in the financial statements. These will ensure that you omit the poorly developed thesis and will show your ability advice people appropriately and even about some considerable sums of money. Are you looking for the service that will meet all your wishes and expectations? We offer you to try Thewritemyessayas it can write the best money management essay. Do not hesitate, submit the request and enjoy your free time.

The Largest Countries by Population in 2100

The Largest Countries by Population in 2100 In 2017, the United Nations Population Division released its World Population Prospects: The 2017 Revision, a set of population projections out to the year 2100 for the planet Earth and for individual countries. The United Nations expects the global population- 7.6 billion as of 2017- to reach 11.2 billion by the year 2100. The report placed current population growth at 83 million people per year. Key Takeaways: The Most Populous Countries in 2100 The U.N. expects the current global population of 7.6 billion to reach 11.2 billion in 2100. Most population growth is expected to take place in a small group of countries, including India, Nigeria, the United States, and Tanzania. In many other parts of the globe, fertility rates are declining, and populations are expected to see little or negative growth. Migration- driven by the effects of climate change and other challenges- is expected to play a larger role in demographic changes over the next century. The United Nations looked at population growth both globally and at the country level. Of the 10 largest countries, Nigeria is growing the fastest and is expected to have a population of nearly 800 million by 2100, making it even larger than the United States. By 2100, the U.N. predicts that only India and China will be larger than Nigeria. The Most Populous Countries in 2100 Current population growth varies wildly from country to country, and the list of the most populous nations in the world is expected to look much different by the turn of the next century. Ranking Country 2100 Population Current Population (2018) 1 India 1,516,597,380 1,354,051,854 2 China 1,020,665,216 1,415,045,928 3 Nigeria 793,942,316 195,875,237 4 United States 447,483,156 326,766,748 5 Democratic Republic of the Congo 378,975,244 84,004,989 6 Pakistan 351,942,931 200,813,818 7 Indonesia 306,025,532 266,794,980 8 Tanzania 303,831,815 59,091,392 9 Ethiopia 249,529,919 107,534,882 10 Uganda 213,758,214 44,270,563 These U.N. projections are based on national censuses and survey data from around the world. They were compiled by the Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat. The full data is available for download in a customized Excel spreadsheet. Compared to current population estimates and 2050 population projections, note the high number of African countries on this list (five out of the top 10).  While  population growth rates are expected to decline in most countries in the world, African countries by 2100 may not experience much reduction in population growth at all. Even some countries whose growth rates are expected to decline will still become much larger, as their growth rates are already relatively high. Most notably, Nigeria is expected to become the third most populous country in the world, a spot long held by the United States of America. Of the five most populous nations in 2100, five are expected to be African countries. About half of the worlds population growth over the next 30 years is expected to take place in only nine countries: India, Nigeria, the Congo, Pakistan, Ethiopia, Tanzania, the United States, Uganda, and Indonesia. Reasons for Population Growth In developed nations around the world- including England, France, and Japan- fertility rates are declining, reducing overall population growth. However, some of the decline in growth is being mitigated by longer life expectancies, which have risen to 69 years for men and 73 years for women. The global increase in life expectancies is due to multiple factors, including a reduction in child mortality rates and improved treatment for HIV/AIDS and other diseases. In most developed nations, populations are expected to see minimal or negative growth over the next century. Diminished fertility rates will result in aging populations, with people over the age of 60 making up about 35 percent of Europes population (they currently make up only 25 percent). Meanwhile, the number of people over the age of 80 is expected to increase as well. By 2100, the U.N. predicts there will be about 900 million people in this age cohort around the globe, nearly seven times as many as there are now. Another reason for shifting populations, the U.N. notes, is migration, and the Syrian refugee crisis, in particular, is expected to substantially increase the populations of Syrias neighbors, including Turkey, Jordan, and Lebanon. Migration is also expected to take place in other parts of the globe, much of it driven by the effects of climate change. As rising temperatures disrupt ecosystems and increase food insecurity, more and more populations will be displaced, causing demographic changes in affected areas. A 2018 report by the World Bank found that worsening climate change could cause more than 140 million people to become climate migrants by 2050.

How to Register as a Government Contractor

How to Register as a Government Contractor For thousands of small businesses, contracting for the sale of their goods and services to the federal government agencies opens the doors of growth, opportunity and, of course, prosperity. But before you can bid on and be awarded government contracts, you or your business must be registered as government contractor. Getting registered as a government contractor is a four-step process. 1. Obtain a D-U-N-S Number You will first need to obtain a Dun Bradstreet D-U-N-S ® Number, a unique nine-digit identification number for each physical location of your business. D-U-N-S Number assignment is free for all businesses required to register with the federal government for contracts or grants. Visit the D-U-N-S Request Service to register and learn more about the D-U-N-S system. 2. Register Your Business in the SAM Database The System Award Management (SAM) resource is the database of vendors of goods and services doing business with the federal government. Sometimes called â€Å"self-certifying,† SAM registration is required by the Federal Acquisitions Regulations (FAR) for all prospective vendors. SAM registration must be completed before your business can be awarded any government contract, basic agreement, basic ordering agreement, or blanket purchase agreement. SAM registration is free and can be done completely online. As part of SAM registration process you will be able to record your business’ size and socio-economic status, as well as all FAR-required solicitation clauses and certifications. These certifications are explained in the Offeror’s Representations and Certifications - Commercial Items section of the FAR. SAM registration also serves as a valuable marketing tool for government contracting businesses. The federal agencies routinely search the SAM database to find prospective vendors based on goods and services provided, size, location, experience, ownership and more. In addition, SAM informs the agencies of firms that are certified under the SBA’s 8(a) Development and HUBZone programs. 3. Find Your Company’s NAICS Code While it’s not absolutely necessary, chances are you will need to find your North American Industry Classification System (NAICS) code. NAICS codes classify businesses according to their economic sector, industry, and location. Depending on the products and services they offer, many businesses may fit udner multiple NAICS industry codes. When you register your business in the SAM database, be sure to list all of its applicable NAICS codes. 4. Obtain Past Performance Evaluations If you want to get in on the lucrative General Services Administration (GSA) contracts and you should want to you need to get a Past Performance Evaluation report from Open Ratings, Inc. Open Ratings conducts an independent audit of customer references and calculates a rating based upon a statistical analysis of various performance data and survey responses. While some GSA solicitations for bids do contain the form to request an Open Ratings Past Performance Evaluation, vendors may submit an online request directly to Open Ratings, Inc. Items You Will Need for Registration Here are some of the things you will need when registering your business. Your NAICS codesYour DUNS - Data Universal Numbering System numberYour Federal Tax Identification Number (TIN or EIN)Your Standard Industrial Classification (SIC) codesYour Product Service codes (optional but helpful)Your Federal Supply Classification codes (optional but helpful) Obviously, all of these codes and certifications are geared toward making it easier for the federal government purchasing and contracting agents to find your business and match it to their specific needs.   US Government Contracting Rules to Know Once you are registered as a government contractor, you will be required to comply with several laws, rules, regulations, and procedures when doing business with the government. By far the two most important of these laws are the aforementioned Federal Acquisition Regulations (FAR) and the 1994 Federal Acquisition Streamlining Act (FASA). However, there are many other laws and regulations that deal with government contracting. Government Contracting Procedures Briefly Each agency of the federal government conducts business with the public through three specific authorized agents, called contracting officers. These officers are: The Procurement Contracting Officer (PCO)- awards contracts and deals with contract terminations in the event the contractor defaults on the terms of the contract.The Administrative Contracting Officer (ACO)- administers the contract.The Termination Contracting Officer (TCO)- deals with contract terminations when the government chooses to terminate the contract for its own reasons. Depending on the situation, the same person may the PCO, the ACO, and the TCO. As a sovereign entity (the sole ruling power), the federal government retains rights that commercial businesses do not have. Perhaps most importantly, the government has the right to unilaterally change the terms of the contract, provided that the changes are within the general parameters of the contract.

Pop Culture Media Critique Essay Example | Topics and Well Written Essays - 250 words

Pop Culture Media Critique - Essay Example As observed ‘Will and Grace’ present the gay community as a society struggling for acceptance while the show ‘The New Normal’ portrays the gay community as an accepted part of the society, even the name suggests the acceptance as it refers to being gay as the ‘new normal’. The United States government thought the governance of George W. Bush greatly supported the theme presented by ‘Will and Grace’ and it offered great support through the broadcast of hundreds of commercials on the sit-com with the help of the Bush campaign during the presidential campaigns. The heterosexual women in both shows play the role of supporting the couple and are used as the audiences judge on the gay characters. They are greatly important as they help the gay couple in understanding their roles as partners and also enabled the audience in the acceptance of the gay in the society showing that they are simply as natural as any other community in the society. For example, the women in ‘The New Normal’ help the couple in acquiring an adopted child. (Will & Grace Season 1 Videos & Clips Online, Trailer: The New

Culinary Tourism Food and Drink Product Inventory Assignment

Culinary Tourism Food and Drink Product Inventory - Assignment Example If the tourist people obtain their home country food in outside nations, they become highly attractive and visit the same in a frequent way (Knight, 2012). In relation to the above context, the assignment intends to create a food and drink inventory and likewise prepare a report based on culinary tourism food and drink products of a destination i.e. Sussex located in New Brunswick in the nation of Canada. Secondary method of data collection is appropriate for this research study to collect information for preparing the food and drink inventory report. It will be vital to mention in this regard that journals, articles and online sources relevant to specific topic of a study are deemed to be the decisive sources of secondary data collection method through which valuable and relevant information can be acquired. Through secondary sources, it is possible to gather accurate and recent information about any stated topic. Secondary data collection is also important for this research study to identify any sort of persisted research problem and derive effective solutions to resolve the same. It will be vital to mention in relation to the above context that the adoption as well as the review of varied secondary sources would certainly provide a better comprehension about how to promote the progression of culinary tourism specifically in Sussex, which is positioned in Canada. Apart from this, s uch sources would aid in examining the varied food products that persist in this specific region (Ut, 2013). It has been earlier mentioned that culinary tourism can also be related to food and drink tourism, which signifies that it is not only limited to food and drink sector, but also correlated to cultural aspects tourism. It can be ascertained that the food as well as drink menu is deemed to be different from one nation to another.

History Essay Example | Topics and Well Written Essays - 500 words - 4

History - Essay Example This is one of those moments that redefined the status of the country as one of the biggest economic powerhouses of the world. It also brought into existence, a large number of fiscal and monetary policies that have been a guiding light for the other economies. During the period of 1920’s, there was a period of great turbulence as the growth among the various sectors was uneven. The period was marked by fall of the farm prices, whereas the industrial profits grew. There was an inflated stock market, which led to the Great depression of 1929. The unemployment increased from three percent in the year of 1929, to almost twenty five percent by 1925. The production fell by one third. These led to large scale reforms in the American economy in the form of a lot of new path breaking laws (the social security Act, Works progress Administration Act, The emergency Banking Act and the Economy Act) (Bordo et al, 1998). World War II The World War II was one of the most defining moments in the history of the United States. Categorically, America had always tried to stay away from the war and had tendered its ideological support to the allies. The main contribution of the US to the war was resources, men, money, and ammunition. That actually triggered to the rise in the GDP.

Globalization, Outsourcing, Off-shoring, and Offshore Outsourcing Essay

Globalization, Outsourcing, Off-shoring, and Offshore Outsourcing Impact on Culture - Essay Example By the first decade of 2000, it had become widespread business practice to contract knowledge reliant work to countries such as India or the Philippines. Now, the number of certain jobs decreases in the United States, but new positions and responsibilities are emerging. Along with risk comes opportunity. Next, we detail how globalization, outsourcing, off-shoring and offshore outsourcing have influenced contemporary culture. The dangers of losing important business skills and dependence upon remote suppliers looms large (Loebbecke, C., Huyskens, C., and Mitev, N.). Team disintegration due to global divisions of labor is problematic. Off shoring has affected job opportunities for graduates of information systems programs. To fill these gaps, American students train to manage offshore operations which has required adaptations of IS curricula globally. Such programs focus on thinking globally but acting locally - a set of independent interrelationships. Finally, we give the modern business person clues to solving the challenge of globalization, outsourcing, off-shoring, and offshore outsourcing.

Microsoft Introduction Research Paper Example | Topics and Well Written Essays - 750 words

Microsoft Introduction - Research Paper Example Bill Gates was the first president while Paul Allen was the executive vice-president (Nell 12) Microsoft a corporation, like others has goals, vision and mission. The vision of Microsoft is to create accessible innovative technology, which sheds light on its mission which is to make people and businesses all over the word to realize their potential. The company’s main focus is on software products and services where they develop and also license them. Microsoft operating systems is among its products that mainly allow a computer to operate. Microsoft has packaging software called Microsoft Office that is used in an office set up which include word processor and spreadsheet among others (Randall 22). Microsoft has had three C.E.O’s since it was found with Bill Gates as the first one and Steve Ballmer being the second. Sadya Natella is the third and current C.E.O of Microsoft. He has been working with the company for more than two decades and he is famous for pushing vigorous changes in the company’s culture and products. This has led to him having a reputa tion of proven potential and capability of being the C.E.O of a big corporation like Microsoft. The company’s main headquarters is on One Microsoft way, in Redmond, Washington, United States of America. Microsoft has put a lot of effort to make sure most parts of the world are experiencing its availability. Branches of Microsoft are mainly found in the United States of America with its subsidiaries in more than seventeen countries. Some of these countries are France, India, Canada, Nigeria and Peru, which mostly deal with its software and programming industry. Microsoft is estimated to have one hundred and twenty eight thousand employees (128,000). Microsoft has been focusing keenly on expanding its markets in all the continents of the world to keep up with competition in the computing world. There are three subsidiaries that I have chosen for this project and they are Microsoft

Globalization, Outsourcing, Off-shoring, and Offshore Outsourcing Essay

Globalization, Outsourcing, Off-shoring, and Offshore Outsourcing Impact on Culture - Essay Example By the first decade of 2000, it had become widespread business practice to contract knowledge reliant work to countries such as India or the Philippines. Now, the number of certain jobs decreases in the United States, but new positions and responsibilities are emerging. Along with risk comes opportunity. Next, we detail how globalization, outsourcing, off-shoring and offshore outsourcing have influenced contemporary culture. The dangers of losing important business skills and dependence upon remote suppliers looms large (Loebbecke, C., Huyskens, C., and Mitev, N.). Team disintegration due to global divisions of labor is problematic. Off shoring has affected job opportunities for graduates of information systems programs. To fill these gaps, American students train to manage offshore operations which has required adaptations of IS curricula globally. Such programs focus on thinking globally but acting locally - a set of independent interrelationships. Finally, we give the modern business person clues to solving the challenge of globalization, outsourcing, off-shoring, and offshore outsourcing.

Choosing the one you love Essay Example | Topics and Well Written Essays - 750 words

Choosing the one you love - Essay Example After the completion of their college studies, both Tom and Julie started their search for employment. Tom succeeded in getting a good job in a highly reputed company located in a city around 200 kilometres away his home. It was difficult and painful for Tom and Julie to separate each other; but both of them agreed to contact each other at least twice in a day. Tom started his career as a computer programmer in that company. Initially, it was difficult for Tom to execute his responsibilities in a timely manner. Diana, another experienced programmer working with Tom, helped him a lot in managing his initial problems in that organization. Both Tom and Diana became good friends within a month. Diana was a charming girl and her mannerisms and behaviour were very much attractive to everybody. She liked modern dresses and looked pretty in her dress codes. Tom’s innocence and mannerisms were caught the attention of Diana. Tom was a strongly built, 6 feet taller handsome young man and Diana slowly started to fall in love with him. Tom realised the intentions of Diana, but it was difficult for Tom to avoid her considering the assistances, he was receiving from her in professional matters. Tom never said anything about his love affairs with Julie. He was afraid of the consequences. He never told Julie also about Diana and her intentions. But he maintained his deep love affairs with Julie. Diana started to give Tom the company on holidays. It was difficult for Tom to avoid the invitations of Diana for watching movies, shopping and spending time on parks and other public gathering places. Diana never asked Tom anything about his past life and Tom never said anything to Diana about his love affairs with Julie. As time passes, Dina’s love towards Tom strengthened and once she revealed her intentions and feelings to Tom. Tom was also started to love her; however it was difficult for him to avoid

Witnesses Fear of Retribution by the Gangs Essay Example for Free

Witnesses Fear of Retribution by the Gangs Essay In America there are a lot of many gangs such as Pico Rivera and Pico Nuevo and many Americans have fallen victims of them. These gangs terrorize people and the police are very determined to control then but their efforts are hampered by one thing, and this is the fact that the witnesses to particular cases refuse to give their testimonies for fear of retribution by the gang members. My focus on this essay is to discuss on why witnesses fear to testify in courts and how this fear should be allayed. According to the deputy attorney general Gary Haearnsberger, out of 258 cases that were heard, over 170 of them were murder cases and witnesses refuse to testify for fear of reprisal by the gang. People feel free to explain to the police what they saw but when it comes to testify in the court they refuse. As per the West Covina detective Dan Nalian in his news report on gangs noted hat there are people who witness shooting scenes and even identify the culprits but when they are asked to be witnesses in court they object. This has even become like a norm in the United States of America that it is not the right thing to testify against any gang for fear that you shall be attacked in retaliation though others refuse to testify due to their criminal related records. A case in point is of 4th March 2005 where a four-man gang tricked a woman claiming that they were his boyfriend’s gang mates only to demand to be directed to them. After they reached where his boyfriend and his two friends were, fierce shooting ensued and a fifteen-year-old boy sustained head injuries while her boyfriend and his partner went unhurt. This woman clearly identified the four-gang members as the residents of Pico Rivera. According to her eye account, these gang members were: Joseph Aranda who was aged twenty years old and Fernando Aranda aged twenty years. She forwarded their names to the police department and promised that she would testify in court against them. But as time went by she could not fulfill the promise she made to the police officers that she would testify in court against them. After a period of three years later the woman refused to testify claiming she couldn’t remember exactly what happened on that fateful day or even remember who the men in a jeep were. Not that it was hard to remember what happened but she feared retribution by the gang. (Gonzalez R. 2008) According the Gary Hearnsberger, the Deputy District Attorney, all gang cases have one thing in common and this is that no one is willing to appear in a courtroom to testify of anything because they fear that the gang who would then seel reprisal would mark them. These gangs have their working code that disallows anybody from testifying against any gang group in court. As per this town code, even the gangsters are not allowed to talk with the police or have any relationship whatsoever. The gang members are very stubborn individuals who are ready to suffer rather than cooperate with the police. They would rather go to jail than reveal their secrets. Many people have been victims of witnesses in courts and these gangs have killed some of them. â€Å"Some gang members live up to this code even if it means going to prison. They see that as a badge of honor, Hearnsberger said. What is kind of funny about the gang culture, as much as they completely disregard rules and laws, they will live up to their own. † (Gonzalez R. 2008) As the president of the California Gang Investigators put it, people confide to the police on everything that they witnessed but when it comes to making a testimony against the gang members it becomes extremely hard. All people should wake up to the fact that gangs rarely attack law abiding citizens and this includes those who are willing to testify in courts on a particular case but this does not mean that they cannot be attacked. In accordance with the 6th amendment, the accused person is entitled to a speedy and public trial conducted by a jury in the place the cat was committed. The accused person must be told in no uncertain terms the reasons for the arrest and then be challenged by witnesses with their evidences or what they saw. The witnesses should be escorted by police officers in and out of the courtroom to prevent them from being attacked by the gangs, as this has been the case in the past. No body should be imprisoned if there is no enough evidence given by the witnesses and the defendant should also be allowed to call his/her witnesses and they should be compelled to testify if they refuse. If the accused persons are capable of representing themselves in court according to the 6th amendment, then they should be given that chance. The defendant is also given a chance to cross-examine the other witnesses who are against them so that the truth could be established. The witnesses from both sides should be protected to allay their fear of retribution. There is nothing that worries the witnesses more than to hear that their families would be attacked just because they tesfied in courts. According to Cmdr. Karpal, witnesses who refuse to testify in court even after they are provided with proper security they should be charged of court contempt like that woman who witnessed robbery and even identified the gang members but when the time for testifying came, she refused to turn up though she was assured of protection by the police. This woman when she was arrested gave an information that contradicted the information that was recorded when she reported the case by saying that she could not identify the gang members. It was later established that this woman was an accomplice of one of the members that were standing on Rex road and this is why one of the reason that was given by the police for witnesses’ failure to testify was that some of them have criminal records though to others it is fear of retribution. (Gonzalez R. 2008) Witnesses should also be fully convinced that they would be guaranteed security even if it means being relocated to another area. The Pasadena police is determined to ensure that witnesses are given the protection they deserve. The Pasadena police are also prepared to arrest those gang members who victimize and intimidate witnesses. If there arises a situation that the gang members are intimidating any witness, then the police would relocate the witness and protect them. For example, the woman who was tricked by the thugs was to be relocated after she reported that those thugs were threatening her. â€Å"Her car was vandalized, she was being stared down and having stuff thrown at her. † (Gonzalez R. 2008) If witnesses could be assured of maximum security, then the fight against gangs would be won, as the main stumbling block is that witnesses fear to testify for fear of reprisal by gang members though there are others who fear to testify because they have some criminal records. The police has come up with a new plan so that they could offer protection to all those that are willing to testify in courts. They also go for those gang members who intimidate witnesses from testifying against their case. Reference. Gonzalez R. 11th March 2008. Witnesses Fear Retribution from Gang Members. Star News Pasadena, CA.

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