Thursday, August 27, 2020

Work At Home and Be Your Own Boss an Example by

Work At Home and Be Your Own Boss To what extent have you been jobless? Or on the other hand on the off chance that you are grinding away, would you say you are the conventional eight to five office laborer or the non-customary business person, who works any place and at whatever point the activity requires you? In the event that you the customary, 40-hrs per week proficient, what amount time do you truly need to spend from home to work and back? Furthermore, what amount time have you truly been gainful? Do you like being pushed around and determined what to do each and every waking hour of the day? It is safe to say that you are fulfilled at how things are in the workplace: with the bundy clock that reveals to you that you ought to have been 10 minutes sooner so your compensation slip would not have been deducted even a solitary penny? Or then again simply being with individuals that you would prefer truly not to be working with around? What about the paper stirs that record up on your table that should be done cont inuously end or, in all likelihood you will be reproved by your chief? Shouldn't something be said about a week ago when you need to do someone elses work on what you are now doing in light of the fact that you have recently arrived in a week or something like that and new representatives are dealt with that way? Need paper test on Work At Home and Be Your Own Boss subject? We will compose a custom paper test explicitly for you Continue Understudies Frequently Tell EssayLab professionals:I'm not in the temperament to compose my article. Since I need to invest energy with my familySpecialists propose: Buy An Essay Which Will Lead You To Your Academic SuccessCustom Writing Service Cheap Custom Writing Service Custom Writing Reviews Best Essay Writing Service Shouldn't something be said about the every day drives? How frequently do you have to get up sooner than expected regardless of whether it is a Monday morning and you have quite recently had a difficult night with your wiped out infant? Or on the other hand consider the odor of different explorers you smell while on board a PUB since you despite everything cannot bear to purchase a vehicle of your own.well, regardless of whether you have your own vehicle, you cannot drive it today since your plate number finishes with a number that isn't permitted to go for that specific day. Have you missed a significant occasion since you need to remain after some time to complete a paper that is expected on a similar day as that unique day of one of your children? Then again, on the off chance that you are the non-conventional worker, have you at any point thought of carrying out a responsibility where you wont be pushed around and advised where and when to be at a particular time? Or on the other hand has it entered your thoughts if there are different open doors where you could do the things you like most, at whatever point and any place you areeven in your night robe? These are only a portion of the inquiries that this book will reply. Functional tips on where and how you may begin functioning at home, where you can deal with your time and your assets and simultaneously appreciate what you do. Perusers will figure out how to win utilizing his PC and his extra an ideal opportunity to create month to month pay. Content Outline: Affirmation Presentation Section I Turn your PC into a lucrative machine Part II Consider Your Work Attitude (What sort of individual right? Is it accurate to say that you are author? On the off chance that an author, okay rather be a fiction or a genuine essayist? Or then again would you say you are adept to maintaining monotonous sources of income? Okay consider organizing? Or on the other hand would you rather give your hands a shot various online organizations? Shouldn't something be said about contributing? Does this intrigue to you?) Section III Transform your considerations into words: A Practical Guide To Article Writing; Some online destinations that offer compensation per-visit; Online-Article Submission Companies Part IV Blog for Profit (Practical Tips for Starters, Pay-Per-Blog destinations) Part V Research Writing: Earn While You realize (What is research composing?; What are the advantages of examination composing?; Practical guide for research scholars; Online organizations offering vocations on research composing) Section VI Teach Online (Is there any subject you feel great imparting to other people? Confer information, meet individuals and gain simultaneously. Remembers tips for web based instructing) Part VI I Receive Pay-Per-Post (Earn as you mingle and talk about anything under the sun; Guide when doing pay-per post; test pay-per-post locales) Section VIII Low Yield (LYOI) versus High return Online Investment (HYOI) (What these are? What are the advantages and disadvantages? Rundown of online organizations offering LYOI and HYOI) Part VIX General Guidelines in searching for the most productive and most appropriate work at home chances End Book Description: Work At Home and Be Your Own Boss tends to one of the most widely recognized concerns however least given thought by many individuals (those working, those unemployed because of state of being, housewives or fathers, school drop outs, retirees), that is the work elective that gives one the joy of working at home. This is planned to be written in a 80-100 pages end table sort book. Market Description: To be composed to assist an assortment of workers and non-utilized. Indeed, even the individuals who are still in school who should gain additional will likewise discover this book engaging as well as productive too. Schools that may discover this book noteworthy and incorporate this to its present prospectus incorporates however not restricted to the accompanying (English Department for the parts on composing and Business Administration for the articles on online business) Creator Description: A work at home mother who invests the vast majority of her energy with her three-year old kid. She is likewise a previous school teacher who instructed Communication subjects. She likewise had related knowledge in radio and furthermore had experience working for government organizations just as for a remote based organization occupied with promoting and dissemination of PC related items. Reference: Laine, Amy, How To Work At Home Without Paying Fees, Retrieved March 10, 2009

Saturday, August 22, 2020

Darkness from Within: Analyzing Hawthorne’s Essay

Nathaniel Hawthorne’s â€Å"Young Goodman Brown† is a chilling investigation of how a man could extend upon others his own murkiness. Through an agreement with the Devil, Goodman Brown gets fixated on the alleged sins of the townspeople. Hawthorne used numerous imageries to delineate how Goodman Brown changed into â€Å"a harsh, a miserable, a hazily thoughtful, a skeptical, if not a urgent man did he become† (91). To utilize a word engaging of numerous individuals today, Goodman Brown turned into a skeptic. So when he kicked the bucket, the townspeople â€Å"carved no confident section upon his gravestone, for his withering hour was gloom† (92). Toward the beginning of the story, Goodman Brown was a guileless youngster who has recently been hitched. He has a fantasy where he sees all the best individuals in the town, including his better half. Apparently, in his involvement in sex in his recently hitched express, the sexuality †the human quality †of everybody, including his better half, his folks, his pastor, and his educators, occurs to him in a horrendous route in that he has consistently been instructed by his Puritan instructors that the substance is wicked. Be that as it may, Goodman Brown had seen both the best and the most noticeably terrible in human instinct. In this procedure, Goodman loses his â€Å"faith† and his adoration and decides to accept the most exceedingly terrible. The story didn't tell everything as simple since perusers are charged to expect that Goodman Brown’s previous honesty had been gotten from obliviousness, as information comes to him with so much force that he can't pardon himself for the numbness that he had. What's more, he accuses every other person since none of them revealed to him these things previously. To put it plainly, he needs to have had divine information, and he along these lines difficulties the method of things in each regard. Just by being human, individuals he sees through his cold eyes change into witches. The individuals who have this cold perspective on others have as of now, amusingly, participated in the devil’s absolution. Like Brown, they everlastingly after will be â€Å"more aware of the mystery blame of others, both in deed and thought, than they could now be of their own† (91). Perusing â€Å"Young Goodman Brown† is a decent inspiration for analyzing perspective †the manner in which we see others. The outcome is an inversion of jobs among great and abhorrence, which resembles the inversion that happened after the insanity of 1692 whereby the â€Å"witches† were seen as saints and the informers and condemners were viewed as persecutors. Hawthorne is keen on what people’s perspectives and judgment enlighten us regarding them, so the concentration in the conversation of black magic is fundamentally on the individuals who see black magic in others. The story is wealthy in imageries thst make up what it needs physical portrayals, which adds to its reader’s puzzlement that all the more frequently becomes dread. In the story, we just realize that Faith has a â€Å"pretty head† (83); that Goodman Brown is youthful; that Goody Cloyse is â€Å"a female figure† (85) who snickers; that Martha Carrier is â€Å"a wild hag† (90); that the group in the woodland is â€Å"a grave and dim clad company† (89). The motivation behind why Hawthorne keeps away from points of interest in this story is on the grounds that the illusion and dubiousness increment the nightmarish air of the story. For example, for what reason is Faith’s â€Å"pink ribbons† is referenced multiple times altogether? What is the importance of the presence of the strips in the forested areas? It would appear to be a solid proof that something awful happened to her. Fogle (1964, p. 18) proposed something else: â€Å"If Goodman Brown is dreaming the lace might be taken as an integral part of his fantasy. . . This pink strip shows up in his wife’s hair again as she meets his on his arrival to Salem the following morning†. For me, what’s all the more terrifying in Hawthorne’s â€Å"Young Goodman Brown† isn't the fallen angel, the black magic or even Brown’s single stroll through the woods at sunset, yet it is the complexity between Brown’s honesty and the detestable that he comes to learn is covered up in his own one of a kind network. Works Cited Fogle, Robert Harter. Hawthorne’s Fiction: The Light and Dark (Norman: Univ. of Oklahoma Press, 1964). Hawthorne, Nathaniel. â€Å"Young Goodman Brown†

Friday, August 21, 2020

Lessons on How to Start a Hard Tech Startup, with Sam Altman

Lessons on How to Start a Hard Tech Startup, with Sam Altman How to know when to jump into a field A photo posted by Michael Cheung (@m_cheung_) on Apr 13, 2016 at 4:07pm PDT If you know anything about startups, you know Y Combinator.  YC has spawned $50 billion worth of startups, including Dropbox and Airbnb, and shows no signs of slowing down.  A common criticism of Silicon Valley startups, however, is that they often go after easy money instead of tackling hard technology problems that have more world-changing potential. Sam Altman (president of Y Combinator) gave a talk today at MIT about why hard tech startups are hard, and why theyre still worth it.  Heres the main lessons I took away from his talk: How to know when to jump into a field 70-80% of the market is chasing the current fad.  This means that if you choose to make a video streaming startup, or a social network startup, youll have an enormous amount of competition both from established companies and other startups. Far better is to think of a new idea that the rest of the world is missing.  Sam says that very few founders do this. Two important factors he stressed when evaluating a field are cost and cycle time.  If the costs in a field have come down recently, or if cycle time has gotten much faster, then it might be a good time to start up in that field (see: genome sequencing). Aim for small wins first Startups survive on momentum.  How do you maintain momentum when youre working on problems with a time scale of many years?  If youre a nuclear reactor startup targeting goals 7 years in the future, what can you deliver in 3 months? The answer is to shorten your cycle time by aiming for small wins early. Instead of the whole nuclear reactor, is there a subsystem that you can deliver in 3 months?  Small wins build on each other and lead to big wins. Momentum attracts good people, and makes people motivated to work harder.  Another benefit of shorter cycle times is that it forces you to build for a real customer; when you have deadlines every few months, its harder to relax too much. Learn from software companies Most of the $10-20 billion dollar companies started in the last few decades have been software companies.  The huge benefit of a software startup is that cost is low, and cycle time is fast. The secret of software companies, Sam says, is that they can aim to get 10% better every week. Short iteration cycles allow them to get feedback from customers and improve their product. Dont be afraid of detours Most founders hate detours, and want to focus on the big picture.  But its often impossible to go from 0 to 100 right off the bat.  For example, take Tesla and its goal of creating a mass market electric vehicle (the Model 3).  Before it got there, it had to start with a high performance, extremely expensive car (the Roadster), then a sporty four-door sedan (the Model S).  These earlier smaller wins are what made the end goal possible.  Another example is SpaceX and its goal of colonizing Mars.  You cant get to Mars without making a lot of smaller wins developing reusable rockets, for example. Why do this at all? The U.S. has seen 200 years of incredible economic growth, and 100 years of territorial expansion.  But today, were in a world of 2% per year economic growth. Sam brought this into the larger context of our current society: people want their life to improve year over year.  But if the pie isnt getting bigger, then for your life to improve you have to take it from someone else.  And this leads to a mess (see: current election year).  Thats why the fundamental motivation of Y Combinator is to reignite technological innovation.  Not just to make money, but to change the world.  And I think thats a goal that MIT can very much identify with.

Monday, May 25, 2020

Essay on The Dark Life and Confessional Poetry of Sylvia...

By the mid twentieth century, the dominance of post-modernist literature began to decline with the emergence of contemporary poets, who brought with them a new type of perspective within their poetry. These poets—especially those who wrote confessional poetry—established their poetry in a single, unified voice that accentuated intimate human topics such as death, sexuality, and family. An important contributor to contemporary and confessional poetry was Sylvia Plath, who employed personal aspects of her life into her style of confessional poetry. Plath suffered from a deep depression that influenced her to often write in a dark, melancholy style. This depression included two suicide attempts of which she wrote before succeeding in suicide†¦show more content†¦This era included several different movements, including imagism, projectivism, beat poetry, and largely, confessional poetry. These different types of poetry, especially confessional poetry, still have a wide influence on American Literature today. If any one group of poets is known to receive the widest amount of praise from academics and critics, it is the group known as confessional poets. Confessional poetry is known to reveal private, intimate experiences with the audience; it is thought of as a way of creating character so as to inform the trauma of the past with understanding and, sometimes, compassion (Hamilton 97). This poetry destroyed the wall between the public and private world, removing with it the taboo label from personal life. It possesses with it a keen interest in the human condition. Though the idea of confessional poetry is not innovative, the way in which contemporary poets employed the idea was. Though confessional poetry is impersonal, that is, objective rather than subjective, many poems were considered the spiritual autobiography of a poet (Malkoff 27). Because their poetry employed very deep, personal ideas, illness and stress were often a part of the live s of confessional poets. Many critics and psychiatrists questioned whether the illness and stress was a price willingly paid for ones art (Malkoff 29) by these poets. These poets included Robert Lowell, Allen Ginsberg, Theodore Roethke, John Berryman, Anne Sexton, and SylviaShow MoreRelatedLife, Poetry, And Death1467 Words   |  6 PagesLife, Poetry, and Death Death, madness, and love are the main points of impulse in Sylvia Plath’s life, a habit that can be described as part of the unconscious. According to psychological studies, the effects of trauma and experience on an author can manifest itself in their writing (Caruth). For instance, we learned that the suffering of Sylvia Plath her whole life due to depression, the attempted of suicide, and the death of her father. Those traumatic experiences influenced the writing and interpretationRead MoreSylvia Plaths Lady Lazarus1289 Words   |  6 PagesSylvia Plath, author of â€Å"Lady Lazarus†, is â€Å"widely considered one of the most emotionally evocative and compelling American poets of the postwar period† (â€Å"Plath, Sylvia: Introduction†). Plath was born in Boston, Massachusetts and her father died when she was eight. Plath attended Smith College and due to overwhelming conditions, she lapsed into a severe depression and overdosed on sleeping pills. Afte r receiving psychiatric care, Plath enrolled in Newnham College where she met and married EnglishRead MoreSylvia Plath is an American Writer who Writes Confessional Poems about her Life1117 Words   |  4 PagesSylvia Plath is an American writer, commonly known for her poetry works. Her poetry can be categorized as â€Å"confessional poetry†, which are poems about the poet’s personal life. Her two most famous published collections of poems are The Colossus and Other Poemsand Ariel, but it was not until after Plath’s death that The Bell Jarwas published. The Bell Jar is considered a more personal and semi-autobiographical novel. Throughout Sylvia Plath’s lifetime, she suffered mentally since she was a littleRead MoreAnalysis Of The Starrry Night Painting By Vincent Van Gogh1373 Words   |  6 Pagesuse them because, in the compilation, they provide a link from the art to the psychological, mental health, and symbolic aspects of Van Gogh’s works. Locating references to support Sylvia Plath’s poem were a bit more challenging, however, I was able to identify four for this evaluation. The first Plath reference, Sylvia Plaths Narrative Strategies is from the Iowa Review published in 1982 by Margaret Dickie. This article delves into Plaths tendency put the reader into the intense emotions of theRead MoreThe Poetry Of Sylvia Plath1811 Words   |  8 PagesSylvia Plath is often described as a feminist poet who wrote about the difficulties women faced before womens right were a mainstream idea. From reading her poetry, it is quite obvious that Plaths feminism is extremely important to her, but she also wrote about a lot of day to day experiences and made them significant through her use of literary devices such as metaphors and symbols. Plath may also be best known for her autobiographical poetry written in a confessional style that appeared duringRead MoreThe Highs And Lows Of Manic Depressive Writing1507 Words   |  7 Pa gesSylvia Plath: The Highs and Lows of Manic Depressive Writing Sylvia Plath, a successful confessional style poet, struggled throughout her life with issues revolving around her father’s death, unsuccessful and unfulfilling relationships with men, and her mental illnesses. Throughout her struggles, Plath wrote, sometimes writing as much as 10 drafts a day. Despite welcoming into the world two children, whom she loved dearly, Plath still felt unfulfilled by her duties as a housewife. As she wroteRead MoreSylvia Plath was American short-story writer, poet and novelist that was born on October 27, 1932900 Words   |  4 PagesSylvia Plath was American short-story writer, poet and novelist that was born on October 27, 1932 in Boston, Massachusetts and died on February 11, 1963. Sylvia Plath is best known for, her books of poems, â€Å"The Colossus and Other Poems Collection† and the â€Å"Ariel Collection† of Poems.Plath’s poetry was known for its rhyme, alliteration and disturbing and violent imagery. Plath’s p oetry is considered part of the Confessional movement, which became very popular in the United States during the 1950sRead MoreOne Art By Sylvia Plath Critical Analysis1446 Words   |  6 PagesLazarus† by Sylvia Plath, the poets write to conceptualize and understand their losses, ultimately applying radically opposing solutions to the same emotional struggle. Elizabeth Bishop was a high-caliber poet known for her excellent use of form and technical genius. Suffering tragedy at a young age when â€Å"her father died, and shortly thereafter, her mother was committed to a mental asylum,† it is somewhat surprising that the majority of Bishop’s poetry is detached from her personal life, instead focusingRead MoreSylvia Plath s Poetry And Her Sanity1075 Words   |  5 PagesSylvia Plath was an American Poet who was renowned for poetry mostly in the United States. She, however lived a difficult and depressing life which led to a few futile suicide attempts, but ultimately led to a successful suicide attempt leaving her children to live on without a mother. This end result was due to a multitude of issues in her life from Sylvia’s sanity. She wasn’t the most stable child. Her marriage also played a role in her suicide. Her successes weren’t acclaimed until after her deathRead MoreThe Colossus and Daddy by Sylvi a Plath802 Words   |  3 Pages Sylvia Plath is one of the greatest poets of all time- the queen of confessional poetry. Her writing is thick with figurative language that cannot be interpreted only one way. Sylvia Plath herself was complicated, and she struggled with her own personal hardships up until the day she took her own life. Plath’s father passed when she was only eight, and she struggled with his absence not only though the rest of her childhood but also into adult hood. Many critics believe her famous poems, such

Thursday, May 14, 2020

Psy 360 Language Essay - 1417 Words

Language Essay Ryan Butler Psychology 360 August 29, 2011 Professor Newlin LANGUAGE Have you ever wondered how we speak? How about why our communication is considered a language and other animal’s communication is not considered language? A wide range of beliefs exist on what defines language. Thus, by exploring the definition of language and lexicon, evaluating language’s key features, the four levels of language structure and processing, and the role of language in Cognitive Psychology, an understanding of what language is becomes clear. Let us begin by defining language and a term named lexicon. LANGUAGE AND LEXICON DEFINITION One big question, when the subject of language comes up, is exactly what language is. What†¦show more content†¦of a word. Also, the Yerkes (2011) text defines Lexicology as a study focusing on the meaning of words. Thus, we see a lexicon as an area in the human brain which stores the meaning, and all aspects, associated with a word. However, to reach the point where a lexicon may be used language must be acquired. To acquire such a skill, one must master the four levels associated with language. FOUR LEVELS OF LANGUAGE To constitute what a language is, four levels of language structure have been established. Specifically, these levels of analysis include phenomes, words, sentences and texts. According to the Willingham (2007) text, phenomes are a small unit of sound which make up a word. A potential problem is if these words are mispronounced. For example, slang changes from one area to another. When a person is thrown a new word, it throws them off on the rest of the topic. If I say Im fixin to go downtown, some may only know fixin as literally fixing something and not preparing or getting ready as fixin means in this context. This non familiar use of a word may be confusing to oneself, but to the person saying the word, â€Å"fixin† is a lexicon built into a vocabulary. Accents of foreigners may be another potential barrier. By mishearing these phenomes and not understanding language due to this deficit, obtaining meaningful language is difficult. Words themselves, and specifical ly the separation of words, may be another potential barrier to languageShow MoreRelatedFate and Destiny7886 Words   |  32 Pagesmeans â€Å"to ordain, to devote, to consecrate† and is connected to the word destination, suggesting that destiny \\server05\productn\T\THE\26-1-2\THE1203.txt unknown Seq: 2 26-FEB-07 9:49 206 Journal of Theoretical and Philosophical Psy. Vol. 26, 2006 includes both a direction and a plan (p. 89). Bollas states that â€Å"[D]estiny is linked to actions rather than words. If fate emerges from the word of the gods, than destiny is a preordained path that man can fulfill† (p. 32). In EnglishRead MoreHuman Resources Management150900 Words   |  604 Pagestraining becomes crucial to acquaint new employees with their jobs and the McDonald’s philosophy of customer service and quality. McDonald’s has taken its Hamburger University curriculum from the United States and translated it into 22 different languages to use in training centers throughout the world. Once training has been done for trainers and managers, they then conduct training for all employees selected to work at McDonald’s locations in the foreign countries.54 Questions 1. Identify cultural

Wednesday, May 6, 2020

Captain Beatty in Fahrenheit 451 Essay - 962 Words

Of all literary works regarding dystopian societies, Ray Bradbury’s Fahrenheit 451 is perhaps one of the most bluntly shocking, insightful, and relatable of them. Set in a United States of the future, this novel contains a government that has banned books and a society that constantly watches television. However, Guy Montag, a fireman (one who burns books as opposed to actually putting out fires) discovers books and a spark of desire for knowledge is ignited within him. Unfortunately his boss, the belligerent Captain Beatty, catches on to his newfound thirst for literature. A man of great duplicity, Beatty sets up Montag to ultimately have his home destroyed and to be expulsed from the city. On the other hand, Beatty is a much rounder†¦show more content†¦He simply attempts to accelerate the task and stolidly states â€Å"We’re due back at the house. Besides, these fanatics always try suicide; the pattern’s familiar† (39). Beatty’s c ruelty is soon accompanied by suspicion towards Montag, and he eventually ends up overturning Montag’s life. Although Beatty’s cruel, insidious personality makes him the quintessence of a villain, his hypocritical words and actions make him much more perplexing. Throughout the novel, Beatty proves to be a well-read person, although he adamantly opposes books. For example, when the old woman stays inside of her burning house just to be with her books, she shouts out â€Å"Play the man, Master Ridley!† (40), originally said by a man condemned to being burned at the stake for heresy in 1555. Beatty understood this quote to the extent that he knew who originally said it and even the date it was said, although he simply explained â€Å"I’m full of bits and pieces . . . most firemen have to be† (40). Later in the novel, Beatty uses his knowledge of literature to confuse Montag in attempts to dissuade him from books. Beatty perverts the original tex ts and quotes several literary works and authors to confuse Montag and at one point arrogantly states that he is â€Å"using the very books you clung to, to rebut you on every hand, on every point! You think they’re backing you up, andShow MoreRelatedCharacter Analysis of Captain Beatty (Fahrenheit 451)1404 Words   |  6 PagesBeatty, the Nearly Enlightened As fire captain, it is Captain Beatty’s job to promote and direct the eradication of knowledge and free thought within his district through the burning of books in Ray Bradbury’s novel Fahrenheit 451. Though one may expect his job to be one occupied by a brutish, obtuse man with a powerful inferiority complex, this is not so: Beatty is obviously intelligent, well-versed in literature, but also completely devoted to the act of book-burning and the structure thatRead MoreFahrenheit 4511365 Words   |  6 PagesBradbury s novel, Fahrenheit 451, was written at the onset of the fifties as a call to the American people to reflect on how the dominant social values of their times were effecting both the lives of individual Americans and their government. Fahrenheit 451 attacks utopian government and focuses on society s foolishness of always being politically correct. (Mogen 113). According to Mogen, Fahrenheit 451 depicts a world in which the American Dream has turned int o a nightmare because it has beenRead MoreFahrenheit 451 symbolism paper1535 Words   |  7 Pages American Literature 11 11 November 2013 Symbolism in Fahrenheit 451 Ray Bradbury, the author of the well-known science fiction novel Fahrenheit 451, was alarmed by how much time he felt the public devoted to watching television in the 1950’s. â€Å"If this [trend of television watching] goes on†¦Ã¢â‚¬  he wrote, â€Å"nobody will read books anymore† (XIII). This thought of a television-obsessed future public frightened Bradbury. He was particularly fearful of how technology might prevent people from formingRead MoreDystopia Depicted in Bradburys Fahrenheit 451 Essay868 Words   |  4 PagesIn Fahrenheit 451, the reader gets a very vivid description of the deplorable dystopian society by reading only the first few pages. Fahrenheit 451 was written by Ray Bradbury in 1953. A dystopia is an imaginary place where everything is as miserable and horrific as it could possibly be for the citizens. Guy Montag is the central character and a fireman, under the command of his superior fireman, Captain Beatty. Montag walks home with seventeen year old Clarisse, who asks him manyRead MoreFahrenheit 451 Vs. 1984970 Words   |  4 PagesFahrenheit 451 vs. 1984 Ray Bradbury and George Orwell share a very similar theme in their two novels, Fahrenheit 451 and 1984. Winston Smith and Guy Montag work within an authoritarian organization, in which, they have opposing views of the authority. The novels are placed in a dystopian setting that the authority believes is a utopia. The dystopian fictions both have very similar predictions of the future. The predictions from these novels have not happened. However, it could be a short matterRead MoreTheme Of Fire In Fahrenheit 4511246 Words   |  5 PagesThe world of Fahrenheit 451 is not a place that one may want to live. It is a dystopian world. With authoritative control and absolutely no individual freedom, the author Ray Bradbury really set out to emphasize not only the need for literature/knowledge but also the power technology holds in his envisioned future. The novel being titled Fahrenheit 451 one might have thoughts of heat or burning or fire. Whether fire is being used as a weapon of destruction or a way to cleanse the impurity in theRead MoreComparison of Mustapha Mond from Brave New World and Captain Beatly from Fahrenheit 451772 Words   |  4 Pages(Arnold Schwarzenegger). I am Comparing and Contrasting 2 different Characters from 2 different books, Mustapha Mond from Brave New World and Captain Beatty from Fahrenheit 451. These 2 books are very similar and different in many ways. They both are similar because of the power or strength they have over people and the way they brain wash them. Captain Beatty somehow persuades people to believe that books are contain unpleasant and contradicting facts and opinions that should be destroyed. But thereRead MoreTheme Of Heroes In Fahrenheit 451701 Words   |  3 Pages Heroes of Fahrenheit 451 A heroes’s actions reflect his character. Montag, Beatty, and, Granger are characters in the novel by Ray Bradbury, Fahrenheit 451. These characters possess motives, commit actions, and have qualities that would classify them as heroes. Only Granger and Montag are heroes while Beatty is the definite antithesis of the two. Montag believes that books shouldn’t be feared and be embraced, Granger leads a society of individualsRead MoreFahrenheit 451 By William Bradbury Essay1179 Words   |  5 PagesThe book Fahrenheit 451 is set in a dystopian, authoritarian world. The main character, Guy Montag, joins a movement for books when he begins to go against his society’s and government’s regulations. It is a book about censorship, individualism, and mass media. Censorship takes away the intentions left by the creator. It becomes bland, and unoriginal. Words set the mood of the story and character’s behavior within a work. It is important for explicit material to remain raw and natural. It is meantRead MoreBiblical And Literary Allusions Of Bradbury s Fahrenheit 451 1735 Words   |  7 Pagesto think individual thoughts, and with this loss comes the all-too-real possibility that dangerous ideas may not be dismissed. If there are no other voices to make an oppressive idea back down, reality could become a dystopia similar to that in Fahrenheit 451. The idea of a dystopia plays a role in the novel through both the story itself and the presence of a Grand Inquisitor figure, but also is presented to pose the question of why a dystopia could occur at all. Before pondering the cause for too

Tuesday, May 5, 2020

Printed Circuit Board free essay sample

PCBs/Overview – Printed Circuit Boards (PCB) †¢ Introduction †¢ Conductors. Supply Planes. Dielectric. †¢ Vias †¢ PCB Manufacturing Process †¢ Electronic Assembly Manufacturing Process 29/09/2005 EE6471 (KR) 263 PCBs/Overview – For electronic assemblies PCBs are substrates providing mechanical support as well as electrical interconnect – PCB: Rigid or flexible substrate with single or multiple layers of conductors separated by insulating layers Note: PCBs are sometimes also referred to as PWBs (Printed Wiring Boards) 29/09/2005 EE6471 (KR) 264 PCBs/General PCB Origin: United States – Therefore: Non-SI units (oz, mil, in) have been universally adopted for specifying PCBs: †¢ Board dimensions in inches (1in = 25. 4mm) †¢ Dielectric thicknesses and conductor widths/spacing in mil (1mil = 0. 001in = 25. 4 µm) †¢ Conductor (commonly copper) thicknesses in ounces (oz) The weight of conductor metal in a square foot of mat erial. Typical copper thicknesses are: 0. 5oz (17. 5 µm), 1oz (35 µm), 2oz (70 µm), 3oz (105 µm)  µ  µ  µ  µ 29/09/2005 EE6471 (KR) 265 PCBs/General – PCB General Dimensional Specifications: †¢ Finished thicknesses – Standard: 31mil, 39mil and 62mil (0. 8mm, 1. 0mm and 1. We will write a custom essay sample on Printed Circuit Board or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page mm) – Non-standard:  » Readily available for high-volume orders  » Board thicknesses: 10mil-125mil (many PCB manufacturers stop at 20mil depending on plating finish) †¢ Maximum dimensions typically 16in x 20in †¢ Irregular shapes/slots etc readily available (routing) 29/09/2005 EE6471 (KR) 266 Prepreg Core PCBs/Stackup Shown: Cross-section of a typical 8layer PCB Stackup Prepreg Core Prepreg Core – Typical PCB Stackup: Prepreg †¢ Alternating layers of core and prepreg †¢ Core: Thin piece of dielectric with copper foil bonded to both sides. Core dielectric is cured fiberglass-epoxy resin †¢ Prepreg: Uncured fiberglass-epoxy resin. Prepreg will cure (i. e. harden) when heated and pressed †¢ Outermost layers are prepreg with copper foil bonded to the outside (surface foils) †¢ To avoid crosstalk: Wires on adjacent signal layers are routed mostly orthogonally †¢ Stackup is symmetric about the center of the board in the vertical axis to avoid mechanical stress in the board under thermal cycling 29/09/2005 EE6471 (KR) 267 PCBs/Conductors – Conductor: †¢ Material: Typically Cu †¢ Number of layers: – Single or multilayer (up to 20 layers, and more) – Dedicated supply layers (also called â€Å"ground layers†, â€Å"ground planes†) – Most popular: 4-8 signal layers plus 4-8 ground layers Material dimensions: – Thicknesses: 0. 5oz-3oz typically. 0. 5oz/1oz standard for inner layers. – Trend: towards 0. 25oz (particularly for laminated IC packages) – Width and spacing: ? 5mil 29/09/2005 EE6471 (KR) 268 Prepreg Core PCBs/Stackup Shown: Cross-section of a typical 8layer PCB Stackup Prepreg Core Prepreg Core Prepreg – Power Planes: †¢ Power planes are typically built on thinnest core available from a fabrication vendor to maximize the capacitance between the planes †¢ Power planes often use thicker copper layers than signal layers to reduce resistance Why power planes? †¢ Provide stable reference voltages for signals †¢ Distribute power to all devices †¢ Control cross-talk between signals 29/09/2005 EE6471 (KR) 269 PCBs/Conductors – PCB sheet resistances †¢ Cu resistivity ? =1. 7*10-8? m †¢ Remember: Sheet resistance†¦ PCB Sheet Resistances at T=300K (TC Copper: +3930ppm) Conductor PCB Copper Track (0. 5oz Cu) PCB Copper Track (1oz Cu) PCB Copper Track (2oz Cu) PCB Copper Track (3oz Cu) Rs in  µ? 971 486 h W L L = R= = Rs h ? W W A Compare to Semiconductor Rs figures: Sheet Resistances Material Metal (Aluminium) (top layer) Metal (Aluminium) (lower layers) Polysilicon (silicided) Diffusion (n+, p+, silicided) Polysilicon (doped) Diffusion (n+, p+) Rs ? 0. 05 0. 1 6 10 30 100 5k several k several Meg in ? ? L L 243 162 n-well Nichrome Mixed signal IC resistor material. Stable and lasertrimmable Polysilicon (undoped) 29/09/2005 EE6471 (KR) 270 PCBs/Insulators – Dielectric Materials: †¢ Typically Fiberglass Epoxy-resin (FR4) – most common, widely available, relatively low cost – rigid structure – temperature range up to 130 °C †¢ CEM: Extremely low-cost. Punchable holes. Also available: – Polyimide: high temperature, rigid or flexible – Teflon: high temperature †¢ Thicknesses – Standard core thicknesses for ML PCBs: 5, 8, 10, 14, 20, 40 mil – Prepreg thicknesses: 4mil typical – Most PCB materials support a (relatively) controlled dielectric/impedance †¢ Suitable for transmission line s 29/09/2005 EE6471 (KR) 271 PCBs/Vias – Vias †¢ Interconnect layers through vias (plated holes) †¢ Via dimensions: – Standard minimum finished hole sizes: ? 8mil – Aspect ratio restrictions apply Aspect ratio of a via: Ratio of board thickness to via diameter. Allows judgement of manufacturability. The larger the aspect ratio, the more difficult it is to achieve reliable plating. Premium charge for aspect ratios 8. 29/09/2005 EE6471 (KR) 272 PCBs/Vias – Vias †¢ Vias require pads on each layer to which they connect. Because the holes are not guaranteed to be perfectly aligned with the copper traces there will need to be an annulus of copper around the plated hole. This is to ensure that the copper won’t be broken by the drilling operation †¢ Pads on inner vias are larger than outer pads to allow for greater dimensional tolerances †¢ Where a via passes through a plane (i. e. ot connect to the plane) a clearance hole is required †¢ Where a via is supposed to connect to a plane, a thermal relief structure is required (usually four small metal bridges between via and plane). Thermal relief is required to facilitate soldering operations. 29/09/2005 EE6471 (KR) 273 PCBs/Vias – Vias †¢ Vias are much larger than signal wires †¢ Vias oc cupy all layers (with the exception of blind and buried vias) †¢ Consequence: Vias reduce wiring density and are therefore expensive! 29/09/2005 EE6471 (KR) 274 PCBs/Special Vias – Vias †¢ Special vias available for high-volume PCBs: Blind vias (connection of outer layer to inner layer) – Buried vias (connection of inner layers preferably on same core! ) †¢ Advantages – Increased wiring density (vias don’t occupy all layers) – Product safety (creepage and clearance distances for electrical insulation) †¢ Penalties: – Restricted choice of suppliers – More complex process:  » Cost  » Reliability Blind Via Via Buried Via 29/09/2005 EE6471 (KR) 275 PCBs/Manufacturing Process – Manufacturing process steps (for a typical rigid multilayer PCB representing about 70% of all PCBs manufactured) †¢ †¢ †¢ †¢ †¢ †¢ †¢ †¢ †¢ PCB data acquisition Preparation of PCB laminate (core) Inner layer image transfer Laminate layers Drilling and cleaning holes Make holes conductive Outer layer image transfer Surface finish Final fabrication EE6471 (KR) 276 29/09/2005 PCBs/Manufacturing Process/Step 1 – Step 1: PCB data acquisition †¢ Files transferred from PCB design house to PCB manufacturing facility: – Gerber files, drill files, fabrication drawings †¢ File review by PCB manufacturer †¢ Creation of PCB tooling – Photo-tool for image transfer Image created by PCB software is reproduced on film using laser photoplotters Drill files – Profile routing files CNC route file – All tooling is stepped and repeated for optimum utilisation of standard panels (24in x 18in) 29/09/2005 EE6471 (KR) 277 PCBs/Manufacturing Process/Step 2 – Step 2: Preparation of PCB laminate (core) †¢ Dielectric material: Woven glass fiber or paper Material depends on the function of the PCB. Some materials perform better in some environments than others (heat, humidity). Some materials are more suitable for particular manufacturing processes (e. g. hole punching). Others again are chosen for electric properties (permittivity). Most widely used: FR4 / CEM Coat/impregnate dielectric material with resin harden †¢ Copper foil is rolled or electrolytically deposited on the base laminate †¢ Core material is sheared to panel size †¢ Core material is cleaned mechanically and/or chemically Removal of surface contamination required to promote subsequent adhesion of photoresist (PR) 29/09/2005 EE6471 (KR) 278 PCBs/Manufacturing Process/Step 3 – Step 3: Inner layer image transfer (photo-lithography) Purpose: Transfer circuit image to core through â€Å"print-and-etch† process †¢ Coat copper foils with photoresist (PR) Negative PR: Light-sensitive organic PR polymerises (â€Å"hardens†) when exposed to light. Polymerised PR will resist etching. †¢ Place phototool and expose to light After expose, PR layer is developed. Polymerised areas remain, unexposed areas are washed away. †¢ Etching Selectively remove exposed copper areas. Etching is performed with conveyorised equipment (etchant flood rinse, several water rinses). Common etchants: Acidic cupric chloride and alkaline ammoniacal. 29/09/2005 EE6471 (KR) 279 PCBs/Manufacturing Process/Step 4 – Step 4: Lamination †¢ Cores are pinned in a stack with sheets of prepreg (b-stage) separating the copper layers. Outer layers are made with a foil of copper †¢ Horizontal alignment critical! Stack is pinned between two heavy metal plates creating a â€Å"book†. †¢ Book is put in a heated hydraulic press for about 2h. Prepreg is available in different styles with varying amounts of resin and glass fibers. This allows the manufacturer to control thickness between layers and thickness of the overall PCB. 29/09/2 005 EE6471 (KR) Outer Cu foil Prepreg Core Prepreg Core Prepreg Core Prepreg Outer Cu foil Temperature (175 °C) Pressure (3000kg) Time (2h) 280 PCBs/Manufacturing Process/Step 5 – Step 5: Drilling and cleaning Purpose: Holes are drilled through PCB to interconnect layers (vias), and to allow the insertion of PTH components Drilling performed with CNC equipment Using drill files. Alternative methods to drilling exist (punching, laser). †¢ Multiple panels can be drilled together Drilling of complex boards can take several hours per load †¢ Desmear Desmear removes the melted resin smear †¢ Etchback Etch glassfibers. Goal: Copper on the inner layers protrude out into the barrel of the hole †¢ Panels are deburred/scrubbed after drilling 29/09/2005 EE6471 (KR) 281 PCBs/Manufacturing Process/Step 6 – Step 6: Make holes conductive PCB substrate is not conductive. Therefore a non-electrolytic deposition method is required. In a later process step, electroplating to the required thickness can be performed †¢ Process: Electroless copper Electroless copper is reliable but alternative methods exist. Electroless copper has some significant disadvantages (like exposure to formaldehyde, which is carcinogen). †¢ Electroless copper bath Deposits 75-125 µIn of copper †¢ Constituents of electroless copper: Sodium hydroxide, formaldehyde, EDTA and copper salt. Complex reaction catalysed by palladium, formaldehyde reduces the copper ion to metallic copper. 29/09/2005 EE6471 (KR) 282 PCBs/Manufacturing Process/Step 7 – Step 7: Outer layer image transfer Most common process: Print, pattern plate, and etch †¢ Coat copper foils with photoresist (PR) †¢ Place phototool and expose to light Outer layer phototools are positive images of the circuit. Circuit image is developed away exposing the copper. PR remaining on the panel will act as plating resist †¢ Pattern plating (copper electroplating) Outer layers will be plated to a thickness of 1. 5mil (to ensure a minimum thickness of 1mil in the holes). Copper electroplating takes place in a copper sulfate bath. Plating is performed at roughly 30A/ft2. Plating duration is roughly 1h. †¢ Plate metallic etch resist †¢ Etching 9/09/2005 EE6471 (KR) 283 PCBs/Manufacturing Process/Step 8 – Step 8: Surface finish Purpose: Prevent copper oxidation. Facilitate solderability. †¢ Most popular surface finish process: SMOBC/HASL: SMOBC: Solder-mask-over-bare-copper. HASL: hot-air-solder-leveling †¢ Solder mask pre-clean (mechanical scrub) †¢ Application of solder mask Purpose of solder mask: Insulate those portions where no solder is required. Most popular mask type: LPI (liquid photoimageable). †¢ Application of flux Provides oxidation protection. Affects heat transfer during solder immersion. †¢ HASL Panels are dipped into molten solder (237 °C). Panels are then rapidly carried past jets of hot air. Exposed copper is coated with solder. Masked areas remain solderfree. Panels are then cleaned in hot water. 29/09/2005 EE6471 (KR) 284 PCBs/Manufacturing Process/Step 9 – Step 9: Final fabrication Mechanical features are added to the board (mounting holes, cutouts, etc) †¢ Routing done through CNC machines †¢ De-panelisation – Partial de-panelisation. Most of the circuit is routed out of the panel, but tabs remain to hold the circuit in place. This allows the assembly machine to populate multiple boards at once. Afterwards, the circuit can be snapped or broken out of the panel. Such panels are called â€Å"breakaways†, â€Å"snaps†, or â€Å"arrays†. – The alternative to partial de-panelisation is to have the panel V-scored. Vscoring is done through a thin rotating scoring blade that will route across the top and the bottom of the panel with about 30% of the thickness of the panel. Vscoring allows more circuits per panel (no spacing is required for routing bits). 29/09/2005 EE6471 (KR) 285 PCBs/Panels – PCB Boards are fabricated in panels to minimise cost of PCB manufacturer and assembly manufacturer – Typical panel dimensions are 18*24in (460x610mm) – Overall board dimensions are kept much smaller than a full panel 9/09/2005 EE6471 (KR) 286 PCBs/Typical Assembly Process – Panel of an electronic unit (left) – Electronic assembly after manufacturing process – Typical manufacturing process: †¢ Silk-screen solder paste onto the panel †¢ Pick-and-place (PP) components (PP machine or manually) †¢ Heavier components and components on bottom side of the board need to be glued down (epoxy-based glue) †¢ Soldering in IR reflow oven (providing the required reflow temperature profile of gradually increasing, sustaining, and removing heat) †¢ Visual inspection (manual or vision systems) †¢ Electrical testing (ATE) 9/09/2005 EE6471 (KR) 287 PCBs/Layout/Do’s and Don’ts – Do’s: †¢ Use (continuous) supply layers whenever possible. Keep connections to supply layers short †¢ Use SMT components wherever possible †¢ Use filter components where required and possible †¢ Place blocking capacitors as close as possible to supply pins of transient loads. Use star-point connections at blocking caps. Signal and Vcc Layer Ground Layer C C 74HCTxxx 29/09/2005 C EE6471 (KR) 74HCTxxx 288 PCBs/Layout/Do’s and Don’ts – Do not’s: †¢ Do not create ground loops! Mutual inductances couple ground loops to other currents loops. Ground loops typically have very small impedances. Currents coupled into ground loops can be very large. They cause problems like ground bounce, signal distortion, etc. Signal and Vcc Layer Ground Layer C C 74HCTxxx 29/09/2005 C EE6471 (KR) 74HCTxxx 289 PCBs/Layout/Do’s and Don’ts – Do not’s: †¢ Avoid discontinuities in grounds layers! High frequency return currents in ground layers follow the path with the least inductance. This path is usually directly underneath the signal trace. If there are discontinuities in the ground layer high frequency currents cannot flow underneath the signal trace. Large loop areas are created, and cause a variety of problems (ground bounce, cross-talk) Signal and Vcc Layer Ground Layer C C 74HCTxxx C PTH connector causing a slot in the ground layer 29/09/2005 EE6471 (KR) 74HCTxxx 290