--The results of performance measurements of modules
BOOKEXCERPT
42
Part III - Gathering Customer Feedback
External shopping This is often called “mystery shopping,” as conducted by “secret shoppers.” In this method, third parties are paid to pretend they are a customer. They visit a location and perform detailed reviews of performance against pre-determined standards and specifications.
Because Mindshare has its roots in mystery shopping, and our executives
have significant experience in all three methods, we feel confident in our
conclusion that, of the three methods, the most important is knowing what
How to measure
When it comes to measuring how well your employees are performing, there are multiple tools at your disposal. There are numerous efficiency and effectiveness measures. They include so-called “hard” measurements, such as units sold, hours worked, customers talked to, complaints resolved, etc.
2022年最新国家开 放大学电大《管理英语4》网络核心课形考网考作业附全答案〖备考〗
2022年最新国家开放大学电大《管理英语4》网络核心课形考网考作业附全答案100%通过考试说明：2022年春期电大把《管理英语4》网络核心课纳入到“国开平台”进行考核，它共有八个单元自测。
针对该门课程，给出了每个单元自测的二套标准题库，在考试中可多次抽取试题，直至与其中的一套答案相近即可。
本文库还有其他网核及教学考一体化答案，敬请查看。
单元自测1第一套一、选择填空题（每题10分，共5题）题目1— This project is too big for me to finish on time.选择一项：C. I'll give you a hand题目2— I think things have been a bit difficult for us the last couple of months.—__________. We've been working hard, but still getting behind.选择一项：A. You're right题目3AT&T found that employees with better planning and decision-making skills were ______ to be promoted into management jobs.选择一项：A. more likely题目4The Human Resource Managing Department at Honda is given specific instructions ______ employ the best possible workers.选择一项：C. on how to题目5The responsibilities in handbook ______ that managers have to be concerned with efficiency and effectiveness in the work process.选择一项：B. indicate题目6二、阅读理解：根据文章内容，判断正误（共50分）。
大学英语阅读三级Passage
大学英语阅读三级PassageThe secret of being born lucky is a summer birthday, with May babies most likely to enjoy a lifetime’s good fortune, according to a study of more than 40,000 people. The time of year at which you are born has an enduring influence on levels of optimism and self-reported luck, according to research by British and Swedish scientists. May was the luckiest month in which to be born, with 50 per cent of those born then considering themselves lucky, while October was the least lucky month, with just 43 percent claiming good fortune.The findings add to growing evidence that the phenomenon of luck is not all down to chance, but is affected by a person’ s general disposition.Other research has shown that whether people think themselves fortunate depends less on objective success than on having a “glass half-full” or “half-empty” approach to life. “What we are seeing suggests that something is influencing how people perceive their luckiness. My hypothesis is that people create their own luck by traits such as optimism, that luck is a psychological phenomenon rather than a matter of blind chance,” said Professor Richard Wise man, who led the research.The pattern of the results, with those born in spring and summer reporting themselves luckier than those born in autumn or winter, could have two potential explanations, Professor Wiseman said.1. According to the passage, whether people think themselves lucky not depends on the following factors EXCEPT ______A) one’s objective success B) one’s general dispositionC) one’s attitude to life D) one’s place of birth2. According to the passage, those who were born in _______ regard themselves as the most fortunate.A) March B) April C) May D) October3. Which of the following statements is TRUE according to the passage?A) Optimistic people tend to be luckier.B) Devoted people tend to be luckier.C) Objective success is more important than one’s general disposition in feeling lucky.D) People drinking more water tend to be luckier.4. Which of the following words can best replace the word “trait”(Line 8, Para.2)?A) quality. B) expectation. C) belief. D) idea.is the best title for the passage?A) Luck is Something Born.B) Luck is Not All Down to Chance.C) Luck is A Matter of Blind Chance.D) Luck and Age.Passage 2Researchers say most of us make instant judgement about a person on the basis of how they look. They say facial features can determine whether we like or trust someone. It may even influence how we vote.“Over the years, we have found that facial features affect the way many of us perceive others,” says Elisabeth Cornwell, a psychology researcher at the university’s Perception Laboratory. Studies suggest that people are less likely to trust those with particularly masculine features, such as a square jaw, small eyesor big nose. “They are perceived as dominant and less trustworthy,” says Ms Cornwell. “It doesn’t mean that men who look more masculine are less trustworthy—It’s just our first impressions. “ Those with less masculine features—larger eyes, a smaller nose and thinner lips—are deemed to be more trustworthy. “We are very good at processing these features quickly,” says Ms Cornwell.The researchers are putting their science to the test at the Royal society’s annual summer exhibition in London. They have subtly manipulated the faces of Prime Minister T ony Blair, Conservative leader Michael Howard and Liberal Democrat leader Charles Kennedy accentuating their dominant and tru stworthy features respectively. “We have u sed a computer programme to change the shape of their face and features. We hope it will help people to understand our work.” So should we expect to see Tony Blair, Michael Howard and Charles Kennedy at the exhibi tion getting tips? “I don’t think it’s something they will want to try,” says Ms Cornwell. “It’s not really possible with television. We all know what they look like. I think they would be naive to try it.”1. Why are people less likely to trust those with particularly masculine features?A) Because they are bad-tempered.B) Because they are perceived as dominant and less trustworthy.C) Because they are perceived as tricky.D) Because they are more stubborn.2. According to the passage, which of the following is perceived as a g masculine feature?A) Larger eyes. B) A square jaw.C) A smaller nose. D) Thinner lips.3. What can be inferred from the passage?A) Most of us tend to judge people by how they look.B) Some studies show that people with particular masculine features are more dominant.C) A candidate with less masculine features is more likely to win a vote.D) Most of us are with masculine features.4. Why will Tony Blair not want to change his facial features according to the passage?A) Because he is so popular that everyone knows what he looks like.B) Because he does not want to get tips.C) Because he has great confidence in his looks.D) Because he is very naive.5.. What is the best title for the passage?A) Facial Features.B) How People Perceive Others.C) Facial Features Are Everything.D) How Facial Features Affect One’s First Impression.Passage 3British university entrants expect to be provided with washing machines and dryers in their rooms, and even car parking spaces, a survey has found. Students are also less prepared to tolerate poor quality living conditions than their predecessors, says the survey by British polling organization Mori.More than 1,000 full-time undergraduates and postgraduates from 21 universities across the UK were surveyed for the research. It shows that location is the key factor in choosing accommodation for students—nearly half of thoseinterviewed said that being close to their place of study was the most important factor in their choice. Cost came second, with evidence that many parents foot the bills for their children’s rent. The survey also shows that students are no longer prepared to carry bags of washing to the nearest launderette. These newcomers expect washers and dryers to be provided with their ac commodation. The study also highlights those things today’s students expect as standard—communal areas to be cleaned regularly, utility bills to be included, even private car parking space to be included.Separate findings from the UK’s National Union of S tudents published earlier this year show more than half of students in private rented accommodation are living in unsatisfactory conditions.1. Who are the subjects of the survey?A) Some oversea students in U. K.B) Some undergraduates and postgraduates in U. K. universities.C) Some graduates in U. K. universities.D) Some British students in other countries.2. What kind of accommodation is the most attractive to students according to the survey by British polling organization Mori?A) An apartment near their universities.B) A cheap house far way from their universities.C) An apartment with car parking space.D) An apartment with washing machines.3. Which of the following statements is TRUE according to the passage?A) The survey described in the passage is conducted by UK‘ s National Union ofStudents.B) Most of the subjects are from universities in London.C) Most college students pay the rent by themselves.D) Students think that communal areas should be cleaned regularly by cleaners rather than themselves.4. According to the passage, the choice of accommodation is influenced by the following factors EXCEPT ______.A) convenience B) comfortC) low rents D) weather5. What does the survey indicate?A) U. K. university students are increasingly satisfied with their living conditions.B) U. K. university students are less and less energetic.C) U. K. university students demand higher qualities of their living conditions.D) U. K. university students pay less and less attention to their studies. Passage 4The former first lady and now New York Senator, Hillary Rodham Clinton, has written a book about her eight years in the White House. It is being released with a great deal of public fanfare. The book reveals details about the notorious Monica Lewinsky scandal involving her husband, President Clinton.In Living History, the wife of former President Clinton recounts the moment when Mr. Clinton informed her that he had, fact, had what he called “a relationship that was not appropriate” with Miss Lewins ky, then a White House intern. She writes, “I’ could hardly breathe. Gulping for air, I started crying and yelling at him. What do you mean? What are you saying? Why did you lie to me? I was furious and getting more so by the second. Hejust stood th ere s aying over and over again, I’m sorry. I’m so sorry. I was trying to protect you and Chelsea, referring to their daughter.”Mrs. Clinton says she hopes that people will read the book for more than intimate details of her troubled marriage. “It’ s a pretty lo ng book, and it’s about my life, and it’s about all of the issues that I’ve worked on, particularly on behalf of women and children, and things that I’ ye cared about literally since I was a little girl,” she said. “I think it will give people more insight and, perhaps, answer questions. It’s also my story.”Publisher Simon & Schuster paid Senator Clinton $ 8 million for the 560-page book, and has ordered an unusually large first printing of one-million copies. Publishing rights to the book already have been sold in 16 countries.1. What appeals to the readers most in the book Living History according to the passage?A) Hilary’s eight years in the White House.B) Hilary’s troubled marriage.C) The issues that Hilary have worked on.D) Hilary’s life as a sena tor.2. The word “notorious” (Line 4, Para. 1) is closest in meaning to______.A) well-known B) unheard-ofC) surprising D) amusing3. Which of the following can best describe Hilary’s reaction when Mr. Clinton told her his inappropriate relationship with Miss Lewinsky?A) Indifferent. B) Calm.C) Angry. D) Astonished.4. What is Hilary’s comment on her own book?A) It is more than interesting.B) It can meet the need of people to know about other’ s intim acy.C) It is an academic bookD) The language of the book is beautiful.5. What CANNOT be inferred from the passage?A) Living History is expected to sell well.B) Living History will be published beyond America.C) Mrs. Clinton is well paid for the book Living History.D) Mr. Clinton is a responsible husband.passage 5The human form of mad cow disease, an incurable, brain-wasting illness that’s killed more than 100 people in Britain, has claimed its first Canadian victim. Canadian health officials confirmed Thursday that the unidentified man died sometime this summer. The man, who lived in the western province of Saskatchewan, contracted the disease from eating contaminated meat while traveling in Britain.Dr. Antonio Giulivi, an official with the government agency Health Canada, quickly moved to calm fears by assuring the public the disease had not entered the Canadian food supply.The variant of the cow-killing illness, known as Creutzfeldt-Jakob disease, is believed to be caused when ground parts of diseased cattle are mixed into cattle feed and those cows are turned into processed meats for human consumption. Though the disease cannot be confirmed until an autopsy is performed on the dead brain, symptoms of human infection include uncontrolled shaking, dementia and finally paralysis.But while government officials insisted safeguards are in place to keep the disease out of Canadian meat, warnings were issued to 71 patients at the hospital where the infected man wastreated before his illness was identified. Those patients had been treated with the same medical instruments used on the diseased man. Though the instruments were cleaned and disinfected, officials said a theoretical possibility remains that those people could have been infected.News of the death initially sent Canadian restaurant stocks into a tailspin, but most of them recovered by the end of the trading session.1. Where is the Canadian supposed to contact mad cow disease?A) In Saskatchewan. B) In Britain.C) In Canada. D) Not mentioned.2. Which part of the body does the mad cow disease mainly affect?A) Hands. B) Legs.C) Brain. D) Liver.3. Why did the Canadian government issue warnings to 71 patients?A) They ever used the same medical instruments with the first Canadian victim.B) They were intimate relatives of the first Canadian victim.C) They had ever traveled to Britain.D) They were supposed to have contacted mad cow disease.4. What did Health Canada do after the mad cow disease infected a Canadian?A) Health Canada concealed the truth by all means.B) Health Canada tried to remove public fear.C) Health Canada succeeded in curing the victim.D) Health Canada tried to find ways to cure the disease.5. What can be inferred from the passage?A) The news of the mad cow disease death has no effect on Canadian economy.B) We can decide whether a person contract mad cow disease by the symptoms of uncontrolled shaking, dementia and paralysis.C) Some cows in Canada contracted mad cow disease.D) The mad cow disease is not completely known to the scientists yet.Passage 6A United Nations report is sounding an alarm on the state of the earth’s natural resources, in advance of this month’ s U. N. -sponsored sustainable development summit in Johannesburg.The report says sea levels rose and forests were destroyed at unprecedented rates during the last decade. It notes that more than 40 percent of the world’s population—two billion people now face water shortages. And it predicts that with the global population expected to increase from six billion to eight billion people over the next 25 years, further environmental stress is expected. . Undersecretary General Nitin Desai says the most important message in the report is that the world’s environmental crises are interrelated. As an example, he cites the “Asian Brown Cloud,” a “poisonous cocktail” of particulate matter, chemicals, and various aerosols currently hanging over a vast area of southeast Asia.“Here you have a situation which arises because of the unsustainable way energy is used in this region, which is leading to these problems which impact on agriculture, on water, on health,” said Mr. Desai. “If you really want to address water, agriculture and health, you have to address energy. You can’t reduce poverty unless you also address land and water. Youcan’t improve children’s hea lth without addressing water and sanitation and air quality.”Mr. Desai, who will lead the Earth Summit, says that governments must form specific partnerships to reduce threats in five areas: water, energy, agriculture, biodiversity and health.1. When is the . report mentioned in the passage released?A) At the sustainable development summit.B) Before the Earth Summit.C) After the sustainable development summit.D) Last year.2. “Asian Brown Cloud” is used as an example to show that ______A) environmental protection needs cooperation.B) Asia is the most polluted area in the world.C) air pollution in Asia is very serious.D) travelers are warned not to visit Asia.3. What results in the problems concerning agriculture, water and health according to the passage?A) The rising sea level.B) The conflicts around the world.C) The improved living standard.D) The unsustainable way energy is used.4. What doe s the word “address” (Line 4, Para. 3) mean?A) Speak to. B) Make a formal speech to.C) Deal with. D) Make use of.5. What can be inferred from the passage?A) Natural resource shortage will be a great problem in the future.B) Poverty can be reduced by increasing production.C) Sustainable development is impossible.D) Southeast Asia is the most polluted area in the world.Passage 7The University of Chicago is a private, nondenominational, coeducational institution of higher learning and research. It is located in the community of Hyde Park—South Ken-wood, a culturally rich and ethnically diverse neighborhood, seven miles south of downtown Chicago.The University was founded by John D. Rockefeller. William Rainey Harper was its first president. Classes began on October 1, 1892, with an enrollment of 594 students and a faculty of 103, including eight former college presidents. In 1930 the undergraduate College and the graduate divisions were created. Such cross-fertilization continues to characterize the University.Candidates for admission to graduate programs in the divisions at the University of Chicago should address their inquiries, including requests for application forms, to the dean of students of the graduate division to which application is being made.An applicant who holds a degree from an accredited institution is considered for admission on the basis of (1) an undergraduate record, (2) a well-organized plan for graduate study, (3) Graduate Record Examination (GRE) and TOEFL scores, where required, and (4) recommendations from three college faculty members acquainted with the character, ability, potential, qualifications, and motivation of he applicant. Persons who have been away from school for several years may submit recommendationsfrom employers, professional associates, or supervisors. Transcripts of all academic work should be submitted with the application if at all possible; the applicant should request eachinstitution attended to provide an official transcript in a settled envelope.I. What can be concluded from the first paragraph?A) Only boys were admitted when the University of Chicago was founded.B) The University of Chicago is mainly financed by the government.C) The University of Chicago is located in the suburb of a city.D) The people of South Kenwood have similar cultural tradition.2. The University of Chicago has long been characterized by _____A) its cross-fertilization B) its long historyC) its excellent teaching staff D) its beautiful campus3. Which of the following statements is TRUE according to the passage?A) The founder of the University of Chicago is also its first president.B) The University of Chicago began to enroll graduates since its foundation.C) Some of its first graduates or teachers became the presidents of its several colleges.D) The University of Chicago has always been reluctant to enroll students from other universities in its graduate programs.4. To whom should the application form for the admission to the graduate programs of the University of Chicago be addressed?A) The dean of students of its graduate division.B) The president of the university.C) The concerning professor.D) Any teachers in the university5. What is NOT a requirement for a graduate who wants to be admitted in the graduate programs in the University of Chicago?A) An undergraduate record. B) GRE scores.C) A detailed plan for graduate study. D) A national examination.Passage 8Internet use appears to cause a decline in psychological well-being, according to research at Carnegie Mellon University. Even people who spent just a few hours a week on the Internet experienced more depression and loneliness than those who logged on less frequently, the two- year study showed. And it wasn’t that people who were already feeling bad spent more time on the Internet, but that using the Net actually appeared to cause the bad feelings.Researchers are puzzling over the results, which were complete contrary to their expectations. They expected that the Net would prove socially healthier than television, since the Net allows users to choose their information and to communicate with others. The fact that Internet use reduces time available for family and friends may account for the drop in well-being, researchers hypothesized. Faceless, bodiless“virtual”communication may be less psychologically satisfying than actual conversation, and the relationships formed through it may be shallower. Another possibility is that exposure the wider world via the Net makes users less satisfied with their lives.“But it’s important to remember this is not about the technology per se ; it’s about how it is used,” says psychologist Christine Riley of Intel, one of the study’s sponsors. “It reallypo ints he need for considering social factors in terms of how you design applications and services for technology.”1. The word “well-being” (Line 1, Para. 1) is c losest in meaning toA) trouble B) health C) depression D) excitement2. What is the intended conclusion of the research conducted by Carnegie?A) Internet use may lead to mental dissatisfaction.B) Internet use is sure to cause a decline in mental well-being.C) People who spend just a few hours on the Internet will be happier.D) People who use TV are less socially healthier than those who use the Internet.3. Which of the following CANNOT explain the result of the research according to the passage?A) Internet users may spend less time with their family and friends.B) The “virtual” communication may be less psychologically satisfying.C) Internet users may be less satisfied with their lives.D) Internet users make too many friends through the Internet.4. What lessons may be drawn from the result of the research?A) We should not have developed the Internet technology.B) We should change the way we use the Internet.C) We need Internet technology very much.D) TV is more useful than the Internet.5. What is the best title for the passage?A) The Popularity of Internet Use.B) The History of Internet Use.C) The Harm of Internet Use.D) The Fast Development of Internet Use.Passage 9The computer virus is an outcome of the computer overgrowth in the 1980s. The cause of the term “computer virus” is the likeness between the biolo gical virus and the evil program infected with computers. The origin of this term came from an American science fiction The Adolescence of P-1written by Thomas J. Ryan, published in 1977. Human viruses invade a living cell and turn it into a factory for manufacturing viruses. However, computer viruses are small programs. They replicate by attaching a copy of themselves to another program.Once attached to me host Program, the viruses then look for other programs to“infect”. In this way, the virus can spre ad quickly throughout a hard disk or an entire organization when it infects a LAN or a multi-user system. At some point, determined by how the virus was programmed the virus attacks. The timing of the attack can be linked to a number of situations, including a certain time or date, the presence of a particular file, the security privilege level of the user, and the number of times a file is used. Likewise, the mode of attack varies. So-called “benign”viruses might simply display a message, like the one tha t infected IBM’s main computer system last Christmas with a season’s greeting. Malignant viruses are designed to damage the system. The attack is to wipe out data, to delete files, or to format the hard disk.1. What results in the wide spread of computer viruses according to the passage?A) The overgrowth of computer.B) The likeness between the biological virus and evil program.C) The American science fiction The Adolescence of P-ID) The weak management of the government.2. What is computer virus in fact?A) A kind of biological virus.B) A kind of evil program.C) A kind of biological worm.D) Something that only exists in the fictions.3. What usually determines the variety of the virus attacks?A) The time the attack is made.B) The presence of a particular file.C) The security privilege level of the user.D) The different ways the virus was programmed.4. What is the harm of “benign” viruses according to the passage?A) “Benign” virus might wipe out data from the computer.B) “Benign” virus might de lete files.C) “Benign” virus might display a message.D) “Benign” virus might format the hard disk.5. Where does the term “computer virus” come from?A) It comes from a play.B ) It comes from a computer game.C) It comes from a science fiction.D) It comes from a news report.Passage 10Fast food, a mainstay of American eating for decades, may have reached a high in the United States as the maturing baby-boom generation looks for a more varied menu. Fast food still represents a $ 102 billion a year industry, but growth has turned sluggish recently amid tough competition from retail food stores and a more affluent population willing to try new things andspend more, analysts say.Signs of trouble in fast food include price-cutting by industry leaders, including efforts by McDonald’s to attract customers with a 55cent hamburger, and major players pulling out or selling. 0’ Pepsico, for example, is selling its fast-food restaurant divi sion that includes Taco Bell, Pizza Hut and KFC. “It’s becoming harder a nd harder for these firms to grow,” said Jim Brown, a professor of marketing at Virginia Tech University. “I think in the United States fast food has reached a saturation point becaus e of the number of competitors and the number of outlets.”Fast-food restaurant revenues grew 2. 5 per cent in 1996, according to industry figures, the slowest since the recession of 1991. That is a far cry from the levels of the 1970s and1980s. According to the Food Marketing Institute, consumers are using supermarkets for 21 per cent of take-home food, nearly double the level of a year ago. While fast-food restaurants still lead, their share slipped significantly, from 48 per cent in 1996 to 41 percent in 1997.1. According to the passage, the following factors EXCEPT _____ lead to the slower growth of fast food industry.A) the tough competitionB) a richer populationC) the saturation of marketD) the lower quality of fast food2. Which of the following signs does NOT show that fast food industry is experiencinga hard time?A) Price-cutting by industry leaders.B) The leading role of fast food in the market of take-home foodC) The selling of KFC.D) The pulling out of some fast food restaurant.3. Who is a strong competitor to fast-food restaurants in the market take-home food according to the passage?A) Supermarkets. B) Chinese restaurants. C) Hotels. D) Groceries.4. What can be inferred from the passage?A) Fast-food restaurant revenues are declining.B) Fast food is very popular in the 1970s and the 1980s.C) The baby boom generation has never liked fast food.D) Rich people like fast food more.5. What is the passage mainly concerned about?A) The popularity of fast food.B) The disadvantage of fast food.C) The troubles of fast food.D) The advantages of fast food.。
Utilization of nucleotide probes for the measureme
专利名称：Utilization of nucleotide probes for themeasurement of specific mRNA for themolecular diagnosis of autosomal recessivespinal muscular atrophy发明人：Khue Vu Nguyen,Charles-MichelWolff,Philippe Poindron申请号：US09938013申请日：20010824公开号：US06924102B2公开日：20050802专利内容由知识产权出版社提供摘要：The present invention concerns the development of a quantitative method for the molecular diagnosis of autosomal recessive spinal muscular atrophy (SMA) by measuring the amount of cytosolic mRNA from human muscle cells. Both the procedure using radioactive material and the Enzyme-Linked Immunosorbent Assay (ELISA) nonradioactive method were developed using P-dCTP labeled and biotinylated nucleotide probes. The results obtained demonstrate that the measurement of mRNA could be used as a quantitative method for the molecular diagnosis of SMA. There was a perfect concordance of the results obtained between the procedure using radioactive material, the ELISA method and the single strand conformation polymorphism (SSCP) analysis regarding the negative and positive SMA samples. The methods developed in this study may be applicable to the diagnosis (detection of homozygous and heterozygous deletions in exons 7 and 8 of the SMN gene) and the control of mRNA concentrations in the future gene therapy of patients with SMA.申请人：Khue Vu Nguyen,Charles-Michel Wolff,Philippe Poindron 地址：San Diego CA US,Strasbourg FR,Plobsheim FR国籍：US,FR,FR更多信息请下载全文后查看。
高级英语第二册第三课词汇,短语,习题答案
Aims：1.To know how to make good conversation2.To trace the history of the King‟s English3.To learn the methods in developing an expository writing,esp. the use of examples4.To analyse the features of spoken English5.To appreciate the language features-------------------------------------------------------------------------------- Teaching Contents1. Exposition2. History of Britain3. Detailed study of the text4. Organizational pattern5. Language features6. The characteristics of spoken English--------------------------------------------------------------------------------Time allocation1.Exposition and history (15 min.)2. Detailed study of the text (105 min.)3. Structure analysis (15 min.)4. Language appreciation (15 min.)5. The characteristics of spoken English (30 min)词汇：intricate (adj) : hard to follow or understand because full of puzzling parts，details，or relationships错综复杂的；难以理解的，难懂的---------------------------------------------------------------------------------- indulge (v.) : give way to one‟s own desire尽情享受；从事于---------------------------------------------------------------------------------- meander (v.) : wander aimlessly or idly；ramble漫步；闲逛---------------------------------------------------------------------------------- conversationalist (n.) : a person who converses；esp．，one who enjoys and is skilled at conversation交谈者；(尤指)健谈者---------------------------------------------------------------------------------- anecdote (n.) : a short，entertaining account of some happening，usually personal or biographical轶事，逸事---------------------------------------------------------------------------------- intimate (n.) : a close friend or companion密友，知己----------------------------------------------------------------------------------on the rocks[colloq．]: in or into a condition of ruin or catastrophe (婚姻)破坏的；失败的musketeer (n.) : (formerly)a soldier armed with a musket火枪手---------------------------------------------------------------------------------- delve (v.) : investigate for information；search发掘；调查(研究)---------------------------------------------------------------------------------- recess (n.) : a secluded，withdrawn，or inner place幽深处---------------------------------------------------------------------------------- desultorily (adv.) : aimlessly；at random随意地；无目的地---------------------------------------------------------------------------------- alchemy (n.) : an early form of chemistry，whose chief aims were to change baser metals into gold：a method or power of transmutation; esp. the seemingly miraculous change of a thing into something better炼金术；变化物质的方法或魔力----------------------------------------------------------------------------------tart (adj.) : sharp in taste；sour；acid辛辣的；尖酸的；刻薄的---------------------------------------------------------------------------------- convict (n.) : a person found guilty of a crime and sentenced by a court罪犯---------------------------------------------------------------------------------- churl (n.) : a farm laborer；peasant农民；庄稼人，乡下人----------------------------------------------------------------------------------rift (n.) : an open break in a previously friendly relationship分裂；失和---------------------------------------------------------------------------------- scamper (v.) : run or go hurriedly or quickly急驰，快跑---------------------------------------------------------------------------------- rendering (n.) : a translation翻译---------------------------------------------------------------------------------- bilingual (adj.) : of，in or using two languages(用)两种语言的---------------------------------------------------------------------------------- intercept (v.) : seize or stop on the way，before arrival at the intended place 拦截；截断；截击。
2020年英语专四单选及答案详解最新资料
2008年51. Our association, which has consistently pressed for greater employment opportunities for the disabled, will publish ____ proposals in the near future.A. theirB. ourC. hisD. its答案：D. 考查物主代词。
逗号与逗号之间的是作为插入语，是association的定语从句，在此association作为一个整体概念出现，且其定语从句中也是用单数谓语动词has pressed，后面对应的物主代词也应该是单数概念的，故选D。
句意：我们的协会一直在敦促给残疾人更多的就业机会，并且讲在最近公布建议书。
publish公布，proposal提议；建议，press for敦促；迫切要求。
52. Had Judy been more careful on the maths exam, she ____ much better results now.A. would be gettingB. could have gotC. must getD. would get答案：D.考查虚拟语气（错综时间虚拟语气）。
从句部分是对过去的虚拟，省略了if，因此出现倒装，但主句部分出现了明显的时间标志词now，可见是对现在的虚拟，故应该是would/could/should/might do的形式，而get为瞬间动词，不用进行时，故选D。
句意：如果朱迪数学考试时更认真一些，她现在成绩就会好多了。
53. Nine is to three _____ three is to one.A. whenB. thatC. whichD. what答案：D。
这是专四考试频考知识点了：A is to B what C is to D，由what引导的方式状语从句。
高中英语人教版(2019)必修 第二册Unit 5 Music-章节测试习题(3)
章节测试题【答题】( ) What can be learned about the author as a baby?A. He helped his mother a lot.B. He learned music from his mother.C. He went to his mother’s workplace.D. He listened to classical music every day.【答案】C【分析】本题考查细节理解。
【解答】由第三段中的as a baby I was taken along to concerts and stages可知，作者常常被妈妈带到工作的地方。
故选C。
【答题】( ) What would the author probably like to do in the future?A. To be a teacher.B. To be a stage player.C. To be an ad designer.D. To be a businessman.【答案】B【分析】本题考查推理判断。
【解答】由最后一段中的a real show business personality可知，作者有可能成为舞台表演者。
故选B。
1.【答题】七选五Deciding whether or not to take part in an extracurricular（课外的） activity can be a challenge（挑战）. Before signing up to play on the volleyball team, first consider the advantages and disadvantages of such a decision.1. ______ Students are successful when they take part in many activities. They do well in their classes and feel more connected to school. Research shows that students in extracurricular activities have better attendance and grades.Extracurricular activities also help students make new friends and lasting relationships. 2. ______ Even though we became friends a long time ago, we are still close today.While these activities have many advantages, students should consider the downside as well. 3. ______ Extracurricular activities can be too much for students who do not practise good time management. Students need to be good at managing their time between different activities.Another downside to extracurricular activities involves transportation. 4. ______ This situation limits students’ extracurricular choices to those outside the school and closer to home. A few of my classmates joined the school’s cultural club. They later discovered that it met after school. These students dropped out of the club because they had to catch their buses.Only you can decide if extracurricular activities are right for you. Activities outside the school can help you succeed in many areas of your life. 5. ______ Are you up for a challenge?A. We were both in the eight-and-under age group.B. Some clubs or sports meet before or after school.C. One downside is that it can create a busy life for students.D. Many students are tired from all the things they have to do.E. Taking part in extracurricular activities has many advantages.F. I met my best friend when we were on the YMCA swim team.G. However, you need good time management skills to deal with a busy life.【答案】E F C B G【分析】本题考查信息匹配。
2021年广东省揭阳市普宁二中高考英语适应性试卷(一)(附答案详解)
2021年广东省揭阳市普宁二中高考英语适应性试卷（一）一、阅读理解（本大题共15小题，共37.5分）ASmith, Williams, Brown are common surnames that you will meet in Britain. However, you may come across some strange English surnames. The following surnames are rare, but they are real.GotobedYou are not going to meet many people with the surname "Go-to-bed". The first recorded person to have this surname was John Gotobedde of Cambridge in 1269. Professor Reaney, an authority on English surnames, explains the surname originated from people who had a bed, which was rare back in the 12th century. People were proud that they could afford to have a bed, thus adding it to their name. Strange but true!OnionsThis surname, which was first popular in France and Ireland before coming over to the UK，dates back to 1279 and identified a person's job. He was either a seller or a grower of the vegetable.NutterNutter means a crazy or silly person in spoken English. You wouldn't usually call yourself a nutter,but it's genuinely a surname that originated from Yorkshire and Lancashire. It's a variation of the old English surnames "Notere"，which means a clerk, and "Nothard"，which means a person that keeps oxen.HardmeatYou might have guessed that "Hardmeat" must have something to do with a family of butchers. In fact,it might just have been a misspelling of the village that the name came from, which was "Hardmead" in England. Wish they had a spellchecker back then!1.Which of the following surnames can tell a family's wealth？______A. Gotobed.B. Onions.C. Nutter.D. Hardmeat.2.What do Onions and Nutter have in common？______A. They originated in the UK.B. They mean silly people.C. They show the occupations.D. They date from the 13th century.3.Where does the surname of Hardmeat come from？______A. A family of butchers.B. A place famous for hard meat.C. A village without a spellchecker.D. An incorrectly-spelt village name.BAustralian magpies（喜鹊）are common in Australia,loved and feared in equal measure. The fear arises from the fact that nesting females aggressively dive at animals - including, or perhaps especially, humans - often drawing blood. The love comes from the fact that they are simply everywhere, easy to identify, and possessed of a song that has come to represent the sound of nature.And also, they seem rather clever. Now, research by zoologists at the University of Western Australia has corroborated this - but their levels of intelligence are dependent on the size of the group they belong to.To reach this conclusion,the Australian scientists examined 56 birds from 14 groups of wild magpies living in the suburbs of Western Australia's capital city, Perth. The groups ranged between 3 and 12 individuals. Each magpie - tested separately to avoid the risk of it getting help from its mates - was put through four tasks that taxed its cognitive（认知的）abilities. These included finding food hidden in a transparent container,finding food hidden in differently coloured containers, and a memory test involving finding hidden food. Adult and young birds were tested repeatedly and the results were clear. The birds that lived in large groups were quicker to master the tasks than those that lived in smaller ones. The difference between intelligent big group members and less intelligent little group members appeared very early in birds' lives.In a paper published in the journal Nature, lead author Benjamin Ashton and his colleagues report that birds living in large groups "show increased cognitive performance". Moreover, this "general intelligence factor" is strongly linked to reproductive（生殖的）success in females. Ashton suggests that the findings indicate the evolution of intelligence is influenced by pressures present in complex social groups. "Our results suggest that the social environment plays a key role in the development of cognition," he says.4.Which word best describes Australians' feelings about Australian magpies？______A. Frightened.B. Loving.C. Mixed.D. Tolerant.5.What does the underlined word "corroborated" in paragraph 2 mean？______A. Assessed.B. Confirmed.C. Disapproved.D. Doubted.6.How were the magpies treated in the research？______A. They were allowed to seek help.B. They were put in containers.C. They were divided into some groups.D. They were studied individually.7.Which of the following can be the best title for the text？______A. Magpies Seem to Be More Social BirdsB. Magpies in Small Groups Often Perform BetterC. Large-group Living Increases Magpies' IntelligenceD. Cognitive Levels Affect Magpies' Reproductive SuccessC"Well, I just wouldn't sit by her, anymore," I said, more bothered than Abby, and Abby listened quietly. "If she says any more rude things to you, I'll go to your teacher and make sure you are never in a situation where you have to sit next to her again."By this time, Allyson, my then eight-year-old, had joined us, listening to every word. Neither of my daughters interrupted as I finished my heartfelt speech, filled with motherly wisdom. Then,as I was telling each of them what I thought right,Allyson's real words of wisdom came about. "Mom," she said. "I was just thinking. Maybe Abby is supposed to be that girl's friend so that she can bear her. Maybe Abby can let that girl see forgiveness and goodness through her. "I didn't expect to become a student. At that moment,I realized that even though I was working hard to wear "Mother's Hat"，the "hat" certainly didn't make me right.In fact, I wanted to pull that hat over my face and hide. On the other hand,it did comfort and surprise me. "Yes, that's a good point, " I commented, forcing a half smile at my girls. "Abby, you handle this situation the way you think is right. " "OK，" she said, giving me a quick hug before walking out of the door and off to school. "Bye, Mom! " Allyson called, following her big sister out the door.I was left alone. In those following quiet moments I was lost in thought and thought about mytwo remarkable daughters, who are little in height but big in heart as well as a lesson - sometimes our children have great lessons to teach us, if we only listen.8.What bothered the author at first？______A. Her daughter's teacher was irresponsible.B. Her daughter hardly communicated with her.C. Her daughter didn't perform well in school.D. Her daughter was badly treated by a classmate.9.What does the author want to convey by "Mother's Hat"？______A. She felt very proud to be a mother.B. She was too strict with her children.C. She found it hard to be a good mother.D. She failed to play the role of the mother well.10.How did the author feel on hearing Allyson's words？______A. Surprised and concerned.B. Ashamed but grateful.C. Embarrassed but relieved.D. Confused and doubtful.11.What conclusion can be drawn from the story？______A. Children are the mirror of their parents.B. Children may be their parents' teachers.C. Listening creates a deeper connection.D. Kindness has the power to make changes.DThe secrets of dreaming are always interesting psychologists. It is generally acknowledged in the field that dreams people have during this time between childhood and full adulthood, that's around 30，are the strongest and most influential. Yet not enough is known about the repeated patterns of dreaming. Researchers are still trying to answer a basic question：How does dreaming relate to the life experiences and developmental challenges？G.William Domhoff and Adam Schneider, at the University of California, help to answer this question by examining the lengthy dream series of two individuals, "Izzy" and "Jasmine". Izzy provided a collection of 4，329 dream reports from between the ages 12 and 25，while Jasmine provided 664 dreams recorded between the ages of 14 and 25.Large collections of dreams like these pose challenges to researchers. Until recently, the means of studying dream series was to employ a team of recorders who take the time to code eachdream for a predetermined number of content categories,and then compare their results. Nowadays,digital technologies enable the analysis of language usage in dreams with high speed, precision, and objectivity. This marks a revolutionary advance in the science of dreaming. However, it can only lead so far.To gain more specific and detailed insights,Domhoff and Schneider tailored word strings for each dreamer, mixing elements of traditional research with digital tools for analyzing large data sets. For Izzy these word strings included "family and relatives"，"celebrities" and "fantasy"，while the word strings they created for Jasmine included "familiar places"，"electrical equipment" and "music". The researchers used these word strings to identify connections between their dreams and real lives. Surprisingly,the results of the analysis revealed a great deal of consistency and continuity in both sets of dreams. Izzy pays much attention to pop culture, and has affection for famous actors. Jasmine is an accomplished musician and performer."The frequencies of dream elements reveal the intensity of the dreamer's personal concern with that element in waking thought," Domhoff and Schneider conclude. For anyone who still claims dreaming is merely random nonsense from the brain and mental world, these findings are hard to explain away.12.What do psychologists agree with about dreams？______A. Dreams are influenced by life experiences.B. Dreaming is never nonsense from the brain.C. Dreams in one's teens and twenties are most intense.D. The patterns of dreaming are usually repeated.13.What does "it" underlined in paragraph 3 refer to？______A. The collection of dreams.B. Research into dreaming.C. The digital method.D. The challenge for psychologists.14.How do the researchers conduct their study？______A. By analyzing large data sets.B. By developing individualized word strings.C. By identifying the patterns of dreaming.D. By making comparison with traditional research.15.Which can be the best title for the text？______A. New tech, new findingB. Dreams：reflections of waking realityC. Lives, languages, dreamsD. Life experiences：elements of mental world二、阅读七选五（本大题共5小题，共12.5分）People have been faced with illness, death, isolation（隔离）or job losses. （1）______ It's hard, but possible. Here are key strategies to cultivate （培养）hope in these trying times. Start with goals. Hopeful people establish clear, achievable goals and make clear plans. They believe in their capacity, and recognize that their path will be marked by stresses, roadblocks and failures. （2）______ When their hopes are frustrated, they tend to become more focused on doing things to achieve their goals and think that desired goals are attainable even if personal resources are exhausted.（3）______ People high on hope spent less time paying attention to emotionally sad or threatening information. In a world filled with options for what we read,watch and listen to maintaining hope may not require us to go after positive information, but it does require that we avoid negative images and messages.Seek community. （4）______ Connection to others allowed us to feel a sense of accountability,to recognize that our work mattered and that we were part of something bigger than ourselves. Health research suggests that sustaining （维持）hope depends partly on the partly on the particular company we keep.Look at the evidence.（5）______ Hopeful people put their trust in data,particularly in the evidence of history. Cultivating and sustaining hope requires that we gather evidence from our own lives, history and the world at large and use that evidence to guide our plans, pathways and actions.In sum,hope is about how we plan and act to achieve what we want. Hard as it is, see the hope and start to achieve it.A. Manage your attention.B. Hope also requires trust.C. Further, hopeful people adapt.D. Hope is hard to sustain in isolation.E. How can we avoid these misfortunes？F. How do we find hope when times are tough？G. The journey of life starts from the set goal.16. A. A B. B C. C D. D E.E F.F G. G17. A. A B. B C. C D. D E.E F.F G. G18. A. A B. B C. C D. D E.E F.F G. G19. A. A B. B C. C D. D E.E F.F G. G20. A. A B. B C. C D. D E.E F.F G. G三、完形填空（本大题共15小题，共15.0分）As she pulled herself over the summit of El Capitan, Emily Harrington knew she had made history. The 34-year-old completed the （1）______ task in 21 hours, 13 minutes and 51 seconds, becoming the first US woman to free（2）______ the difficult Golden Gate route. Since she started climbing as a 10-year-old, El Capitan has fascinated Harrington. She's spent numerous hours practicing to become（3）______ to climbing it. Free climbers use just their hands and feet to climb,with a（4）______ to catch them if they fall. Such a high risky and （5）______ life-threatening challenge requires years of preparation, both mentally and physically. However,an attempt last year ended in disaster after Harrington hit her head on a rock, and suffered concussion（脑震荡）.（6）______ ，she did not suffer any long-term injuries. It's absolutely a mental（7）______ to return this year and try again. Harrington was pushed to her limits when she fell,her hands（8）______ when at approximately 2，800 feet off the ground. It felt like a（9）______ fall,for the rope was going to catch her. But she felt the（10）______ of blood pouring down her face. She realized that she had hit her head （11）______ .The wound on her head was deep and it seemed as though the challenge would have to be （12）______ again. But this time she hadn't suffered concussion. Stopping the blood flow and determined not to let another fall（13）______ her dream, Harrington had one more go. "We should be less afraid to be afraid. It's a very valid emotion we shouldn't（14）______ from. In many ways,we can use it as fuel and strength." Harrington is currently staying put during thepandemic, hoping to be（15）______ climbing around the world when it's safe. More dangerous trips come after a lot of thought.21. A. easy B. huge C. rigid D. urgent22. A. climb B. visit C. walk D. measure23. A. accustomed B. addicted C. attached D. devoted24. A. chain B. rope C. companion D. doctor25. A. randomly B. wholly C. potentially D. absolutely26. A. Unfortunately B. Unexpectedly C. Consequently D. Luckily27. A. campaign B. task C. struggle D. request28. A. holding B. slipping C. stretching D. rubbing29. A. elegant B. sudden C. safe D. risky30. A. thickness B. freshness C. coldness D. wetness31. A. again B. hard C. straight D. opposite32. A. continued B. abandoned C. experimented D. undertaken33. A. follow B. realize C. change D. steal34. A. shy away B. build up C. turn off D. take down35. A. down B. on C. forward D. back四、语法填空（本大题共1小题，共15.0分）36.China has by far （1）______ largest high-speed railway network in the world.Itshigh-speed rail system stretches over 38，000 kilometers ，which is almost enough （2）______ （circle）the earth once, and is still growing. Currently it（3）______ （make）up 70 percent of the world's high speed rail systems. The network is so extensive thatnearly all big Chinese cities can be reached by high-speed trains.China's rail system also operates in extreme locations such as on the plateau and desert in northwestern China as well as in cities in southern China, （4）______ have a 3-month rainy season every year.The overall design and core technologies of the Fuxing high-speed train wereindependently developed in China,which has independent intellectual property rights of those developments. Among the 254 important standards, Chinese standards account for84 percent. To date, China's high-speed rail products and technology（5）______ （export）to nearly 100 countries and regions on six continents.To our（6）______ （amaze），China has set a new record by developing and（7）______ （build）the world's first locomotive prototype（机车原型）using high-temperaturesuperconducting magnetic levitation technology（HTS Maglev高温超导磁悬浮技术）and the trains will run（8）______ （fast）than any other train in the world as they have been designed to run（9）______ a speed of 620 kilometers per hour. "It's been 20 years in the making. In 2000，our lab developed a small prototype carrying five people using this technology. I'm thrilled to see that we are able to build this to carry so many people in 2021，" said Zhang Jinkai, a graduate student from Southwest Jiaotong University who has been（10）______ （close）working on the project.五、书面表达（本大题共2小题，共40.0分）37.假定你是李华，请给你的外教John Smith 写一封信，邀请他参加你校中华传统文化艺术节的闭幕式晚会。
全新版大学英语第二册unit1课后练习题详解及翻译
Language FocusVocabularyI.1. Fill in the gaps with words or phrases given in the box. Change the form where necessary.1) insert【译文】使用这台机器首先需要投入合适的硬币，然后挑选你喜欢的饮料并按下按键。
2) on occasion【译文】史密斯教授不仅能翻译法语，有时也翻译波兰语。
3）investigate【译文】食品化学家将会对市场上出售的保健食品进行调查，看其是否具备所称的功效。
4）In retrospect【译文】回想起来，当时在这个城市创建的数据处理中心真是不合时宜。
5）initial【译文】我对这个消息的第一反应是如释重负，但仔细一想又觉得愤怒。
6）phenomena【译文】丰富的数学知识足以解释许多自然现象。
7）attached【译文】邮寄包裹前请确保标签已经贴牢。
8）make up for【译文】作为他前一天迟到的补偿，我男朋友请我吃晚饭。
9) is awaiting【译文】委员会正等候总部的决定，然后再采取行动。
10）not…in the least【译文】自己一个人呆在屋子里，这个小姑娘似乎一点儿也不害怕。
11）promote【译文】世界贸易组织宗旨是促进各成员国之间的贸易往来。
12）emerged【译文】当月亮从云层后面露出来的时候，我看见远处有个人影在走动。
2. Rewrite each sentence with the word or phrase in brackets, keeping the same meaning. The first part has been written for you.1) a striking contrast between the standards of living in the north of the country and the south 【译文】该国南北方生活水平差异很大。
人教版高一英语必修一Unit2知识梳理、重点词汇解析
人教版高一英语必修一Unit2知识梳理、重点词汇解析常言说:万事开头难。
还常说,能有一个好的开头,就是胜利的一半;即使不能有一半的胜利,也为今后打下好的基础。
进入高一学好英语打好基础很重要，以下是整理的高一英语学习文章。
人教版高一英语必修一Unit2学问梳理、重点词汇解析及单元自测Unit2一、学问点1. go to the pictures去看电影(美);go to the movies 去看电影(英)2. list the countries tht use English s n officil lnguge 列举把英语用作官方语言的GJ3. the rod to 通向之路4. t the end of在末端，在尽头，by the end最终(=finlly)5. becuse of 因为(留意和becuse 的区分)Mny beutiful fish re fst disppering becuse of the severe pollution.因为污染严峻，很多秀丽的鱼类正在面临绝种。
n rgument ws inevitble becuse they disliked ech other so much.争辩是不行幸免的，因为他们彼此特别厌恶。
6. ntive English spekers 以英语作为母语的人7. even if (= even thoug)即使，用来引导一个让步状语从句，后面既可用陈述语气，也可用虚拟语气，但是even if/even though,引导的从句中不用将来时。
如：Even though/if it rins tomorrow, we will leve for Beijing.8. come up 走上前来，走近，发生，出现come up with 追上，赶上，提出9. ctully ll lnguges chnge nd develop when cultures meet nd communicte with ech other.事实上，当不同文化互相沟通渗透时，全部的语言都会有所进展、有所改变。
publish performance test result report
Publish Performance Test Result ReportIntroductionIn the realm of software development, performance testing plays acrucial role in evaluating the efficiency and responsiveness of an application. One of the key deliverables of performance testing is the performance test result report. This report serves as a comprehensive summary of the testing process, the analysis of the results, and recommendations for improvement. In this article, we will delve into the importance of publishing a performance test result report and exploreits various components.Why Publish Performance Test Result Report?Publishing a performance test result report is essential for several reasons:1. Transparency and AccountabilityBy publishing the test result report, the development team demonstrates transparency and accountability to stakeholders, including clients, management, and end-users. It allows them to understand the performance characteristics of the application and make informed decisions based on the results.2. Benchmarking and ComparisonThe test result report provides a benchmark for future testing and allows for comparisons between different releases or versions of the software. By analyzing historical data, the development team canidentify performance trends and track improvements over time.3. Identification of Bottlenecks and IssuesThe report highlights performance bottlenecks and issues encountered during the testing process. It provides valuable insights into areas of the application that may need optimization or further investigation.4. Justification for Performance Improvement EffortsA well-documented report serves as justification for investing time and resources in performance improvement efforts. It provides evidence of potential risks and the impact they may have on user experience, business operations, and reputation.Components of a Performance Test Result ReportA comprehensive performance test result report consists of several key components:1. Executive SummaryThe executive summary provides a high-level overview of the testing process, key findings, and recommendations. It is designed to give stakeholders a quick understanding of the report without delving into technical details.2. Testing MethodologyThis section details the testing approach, tools used, and the environment in which the tests were conducted. It outlines the objectives of the performance test and the metrics used to measure the performance of the application.3. Test Scenarios and ResultsIn this section, different test scenarios are described and the corresponding results are presented. It includes metrics such as response time, throughput, CPU and memory utilization, and error rates. These metrics are often compared against predefined performance targets or industry benchmarks.Sample Test Scenarios:1.Simulating 100 concurrent users accessing the login page.2.Stress testing the application with gradually increasing load forup to 1000 concurrent users.3.Analyzing the system under peak load conditions for sustainedperiods.Sample Test Results:Test Scenario Response Time (ms) Throughput (requests/sec)Scenario 1 250 50Scenario 2 350 40Scenario 3 800 204. Analysis and RecommendationsBased on the test results, this section provides a detailed analysis of the application’s performance characteristics. It identifies bottlenecks, potential areas of improvement, and recommendations for mitigating performance issues. It may also include comparisons with previous tests or industry standards to provide additional context.Sample Recommendations:•Optimize database queries to reduce response time.•Scale the infrastructure to handle the expected user load.•Implement caching mechanisms to improve overall performance.5. ConclusionThe conclusion summarizes the key findings of the report and reiterates the importance of addressing performance issues. It may also outline the next steps, such as further testing, performance tuning, or additional analysis.ConclusionPublishing a performance test result report is crucial for ensuring transparency, accountability, and improvement in software applications.It provides stakeholders with valuable insights into the application’s performance characteristics and guides decision-making processes. Awell-crafted report, including an executive summary, testing methodology, test scenarios and results, analysis with recommendations, and a conclusion, is vital for effective communication and continuous performance optimization.。
欣喜若狂钢琴比赛作文英语
The exhilarating experience of participating in a piano competition is one that can leave a lasting impression on any musician.Heres a detailed account of such an event, written in English,that captures the essence of the excitement and joy that comes with it.As the curtains drew back,the stage lights illuminated the grand piano,casting a warm glow over the polished ebony surface.The audience hushed,their anticipation palpable in the air.I stood backstage,heart pounding in my chest,a mixture of nerves and excitement coursing through my veins.The moment I had been preparing for had finally arrived.Months of practice,countless hours spent perfecting each note,every crescendo and decrescendo,all culminating in this singular performance.I took a deep breath,feeling the weight of the moment,yet also the thrill of the challenge.Walking onto the stage,I felt a rush of energy.The audiences gaze was upon me,but instead of feeling overwhelmed,I felt a surge of confidence.I approached the piano,my fingers lightly touching the keys,almost as if greeting an old friend.As I began to play,the music filled the concert hall,each note resonating with the passion and dedication that had gone into my practice.The melody soared,the harmonies intertwined,and the rhythm pulsed with life.I was completely immersed in the music, my fingers dancing across the keys with a fluidity that felt almost effortless.The piece I had chosen was a challenging one,full of technical demands and emotional depth.But as I played,I felt a connection to the music that transcended mere technique.It was as if the composers spirit was guiding my hands,the music flowing through me as naturally as breathing.The audience was captivated,their silence a testament to the power of the music.I could feel their collective emotion,their shared experience of the music,and it fueled my performance,pushing me to reach new heights of expression and nuance.As the final notes of the piece rang out,the silence was broken by a thunderous applause. The audience rose to their feet,their cheers and whistles a validation of my efforts.I stood,humbled and grateful,basking in the warmth of their appreciation.Winning the competition was a bonus,but the true victory was in the joy of sharing my love for music with others.The sense of accomplishment,the knowledge that I hadtouched the hearts of the audience,was a reward beyond any trophy or medal.The piano competition was more than just a test of my skills it was a celebration of music and its ability to inspire,to connect,and to uplift.It was a moment of pure joy,a memory that I will cherish forever,and a reminder of the power of music to bring people together in a shared experience of beauty and emotion.。
2022年大学英语三级英语B级考试真题及答案38
2022年大学英语三级英语B级考试真题及答案一、Listening Comprehension1、Section ADirections: This section is to test your ability to give proper answers to questions. There are 5 recorded questions in it. After each question, there is a pause. The questions will be spoken two times. When you hear a question, you should decide on the correct answer from the 4 choices marked A, B, C and D. 听力原文：How long will the play last?(1)A.About 50 pages.B.It is very long.C.About 2 hours.D.It is 2 hours.2、听力原文：Can you tell me when the next bus for London leaves?(2)A.Three-thirty.B.By gate 12.C.A moment ago.D.At the Bus Station.3、听力原文：I don't feel like going to the cinema. Any other ideas?(3)A.Yes, I'll go with you.B.No, I don't like it.C.It's my pleasure.D.What about going to the beach?4、听力原文：Could you help me with the luggage, please?(4)A.No problem.B.What is it?C.Sorry, I don't know.D.Yes, I could.5、听力原文：May I have some information about opening an account here?(5)A.How much do you plan to save?B.What would you like to know?C.You have the right.D.You are welcome.6、Section BDirections: This section is to test your ability to understand short dialogues. There are 5 recorded dialogues in it. After each dialogue, there is a recorded question. The dialogues and questions will be spoken two times. When you hear a question, you should decide on the correct answer from the 4 choices marked A, B, C and D.听力原文：M: Hurry up, or we'll miss the train.W: Is it really so late? It's only two o' clock.Q: What does the woman mean?(6)A.They must hurry up.B.They will miss the train.C.They won't take this train.D.They won't miss the train.7、听力原文：M: Say something about your trip to Paris. W: Well, I visited a lot of good places, and ate in some good restaurants.Q: What's the woman talking about?(7)A.A trip she took.B.A party she attended.C.The place she wanted to go.D.The restaurant she ate in.8、听力原文：M: Excuse me, could you tell me how to get to the shopping centre?W: Certainly, but it's quite a long way.Q: What does the woman mean?(8)A.He doesn't know how to get to the shopping centre.B.He only knows one way to get to the shopping centre.C.The shopping centre is round the corner.D.The shopping centre is a bit far away.9、听力原文：M: Mrs. Wang, what was the hotel like?W: Oh, I stayed in the most comfortable hotel in the city. Q: What does the woman think of the hotel?(9)A.Terrible.fortable.C.Noisy.D.Expensive.10、听力原文：M: How many students took part in the competition? W: About 20, but only 4 got the prize.Q: How many students got the prize?(10)A.Four.B.Twelve.C.Twenty.D.Sixteen.11、Section CDirections: In this section you will hear a short recorded passage. The passage has some words or phrases missing. The passage will be read three times. During the second reading, you are required to put the missing words or phrases on the blank in order of numbered blanks according to what you hear. The third reading is for you to check your writing. Now the passage will begin.听力原文： We usually think that people have five senses. Senses are the way we learn about what is happening around us. The five main senses are sight, hearing, touch, taste and smell. Each sense depends on a certain part of the body. This part of the body receives information and then .sends the information to file brain. Besides these five senses, there are also some other senses. There is a sense of balance which stops us from falling down. We also have senses of hunger, thirst and cold.We usually think that people have five senses. Senses are the 【B1】______ we learn about what is happening around us. Thefive main senses are 【B2】______ ,hearing,touch,taste and smell.Each sense 【B3】______ a certain part of the body. This part of the body receives information and then 【B4】______ the information to the brain. Besides these five senses, there are also some other senses. There is a sense of balance which stops us from 【B5】______.We also have senses of hunger, thirst and cold.【B1】12、【B2】13、【B3】14、【B4】15、【B5】二、Vocabulary and Structure1、Section ADirections: In this section, there are 10 incomplete sentences. You are required to complete each one by deciding on the most appropriate word or words from the 4 choices marked A , B, C, and D.Jerry received a letter yesterday ______ that he got the job.A.speakingB.sayingC.tellingD.talking2、 The salesman had to ______ the conversation in order to wait on a customer.A.break offB.break awayC.break inD.break up3、 I think it is hard to ______ what you said.A.ensureB.convinceC.agreeD.believe4、 I wish we had a colour television. I'm ______ pictures in black and white.A.tired ofB.interested inC.fond ofD.fed up5、 By the time you get there tomorrow,they ______ for Beijing.A.will have leftB.are leavingC.will leaveD.are to leave6、There has been an immediate ______ against their government's proposed tax increases.A.applicationB.reactionC.associationD.reception7、It’s necessary that the problem ______in some way or other.A.is settledB.was settledC.be settledD.has been settled8、 You'd better ______ the water until it has been boiled.A.not to drinkB.not drinkC.not drunkD.not drinking9、 It will only ______ me a minute to repair your shoes.A.giveB.makeC.keepD.take10、 The days ______ you could travel without a passport are gone.A.of whichB.on whichC.in whichD.at which11、Section BDirections: There are 10 incomplete statements here. You should fill in each bland with the proper form. of the word given in the brackets.The manager has received only one (apply) ______for the post.12、 Don't you think their rents (reason) ______?13、 The wine is in the fridge ——it just wants (cool)______ for a couple of minutes.14、 If I hadn't driven the car yesterday, I (avoid) ______ the accident.15、 Hearing the bell ring, the students stopped (joke)______with each other.16、 Mary had made up her mind to go and what I said to her didn't make any (different) ______.17、 Seeing nobody in the classroom, he decided to stay there (read) ______ for a while.18、I thought his explanation was (unnecessary) ______ complex.19、 The girls happily look forward to (see) _______ the movie star at the party.20、 Could you go to bed (early) ______ than you usually do?三、Reading Comprehension1、Task 1Directions: After reading the following passage, you will find 5 questions or unfinished statements, numbered 36 through 40. For each question or statement there are 4 choices marked A, B, C, and D. You should make the correct choice.Doctors believe that second-hand smoke may cause lung cancer in people who do not smoke. Nonsmokers often breathe in the smoke from other people's cigarettes. This is second-hand smoke. The U. S. Environmental Protection Agency (美国环保局) reports that about fifty-three thousand people die in the United States each year as a result of exposure (暴露) to second-hand smoke.It is harder for children to avoid second-hand smoke. In the United States, nine million children under the age of five live in homes with at least one smoker. Research shows that these children are sick more often than children who live in homes where no one smokes. The damaging effects of second-hand smoke on children also continue as they grow up. The children of smokers are more than twice as likely to develop lung cancer when they are adults as children of nonsmokers. The risk is even higher for children who live in homes where both parents smoke. People are becoming very aware of the danger of second-hand smoke. As a result, they have passed laws that prohibit people from smoking in many public places. Currently, 45 states in the United States have laws that restrict, or limit, smoking. The most well-known law doesn't allow people to smoke on short native airline flights, i. e. flights within the country.Compared with nonsmokers' children, the children whose parents both smoke are likely to ______.A.grow up more slowlyB.be sick under the age of fiveC.develop lung cancer more oftenD.become smokers more easily2、Why are there laws made against smoking in public places in the U.S.?A.Because people have realized the danger of second-hand smoke.B.Because more and more people don't like smoking now.C.Because parents don't want their children to become smokers.D.Because the government wants to limit the production of cigarettes.3、Which of the following statements is TRUE?A.The number of smokers' children is twice greater than that of nonsmokers' children.B.People are now allowed to smoke on airline flights in the U. S. .C.Adults whose parents smoked when they were children get cancer more frequently.D.Second-hand smoke is not as dangerous as first-hand smoke.4、From the passage we can conclude that ______.A.the main cause of lung cancer is second-hand smokeB.most people know nothing about the danger of second-hand smokeC.public places are dangerous for people to stayD.children suffer most from second-hand smoke5、This passage is mainly about ______.A.how people get cancerB.who can get cancer easilyC.what should be done with smoking in publicD.whether second-hand smoking can be harmful6、Task 2Directions: This task is the same as Task 1.The 5 questions or unfinished statements are numbered 41 through 45.As working women continue to receive better and better wages, house wives still work at home without receiving paychecks. Should a woman who works at home, doing the housework and caring for children, be paid for her services? In a 1986 study at Cornell University, it was found that the value of the services of a housewife averaged ＄ 11,600 a year. This rate was based on a family com posed of a husband, wife, and three young children. The ＄11,600 is what the husband would have to pay if he hired others to take over his wife's household work. The researchers concluded that it would be fair for husbands to pay wives according to government guidelines(方针)for leastamounts of wages.Another plan for rewarding women who work at home has been suggested by Dr. Johnson, a former Secretary of Health and Human Services. He says that full-time housewives should be allowed to pay social security taxes(社会保障金) ,with their employers (that is ,their husbands) offering part of the payment. He feels that the present system is unfair. He said, "If you work in a store you can qualify for Social Security, but if you stay at home and raise a family, you can't qualify for it."Now in the U. S. the women working outside home can get______.A.the same pay as those doing houseworkB.as much as their husbandsC.an average payment of ＄ 11,600 a yearD.more and more money7、The researchers at Cornell University suggest that _______.A.husbands hire others to do their houseworkB.husbands pay their wives for their work at homeC.policies he worked out on women' s wagesD.women go out to work instead of working at home8、The expression "full-time housewives" in paragraph 2 means______.A.wives who can' t do any houseworkB.wives who don' t like to stay at homeC.wives staying at home doing houseworkD.wives working outside home sometimes9、Why do some people feel that husbands should pay their wives for their housework?A.Because husbands are employers.B.Because raising a family needs money.C.Because wives' work at home has its value.D.Because wives can't qualify for Social Security.10、Why does Dr. Johnson think that the present system is unfair?A.Husbands are paying the social security taxes for their wives.B.Women working at home can't get social security.C.Bosses refuse to pay part of the taxes for female employees.D.Full-time housewives are required to pay social security taxes.11、Task 3Directions: The following is a passage. After reading it, youare required to complete the outline in the table below (No.46 through 50).You should write your answers briefly (in no more than 3 words) on the blanks.Miracle of the ForestWhen you walk into a National Forest, you really believe you're the fist person who's ever been here. Funny thing is, you're not.These forests have been used for over a hundred years. From this timber stand(堆木场) ,settlers used wood to build their homes. And ties(枕木)were cut for the railroad. Hard to believe, isn't it? But that's the Miracle of the Forest. With careful management these forests have renewed themselves, year after year providing us with all kinds of benefits. And that's why we call them" For ever Forests".Come to see for yourself! And get involved with the new "Forests For Us” program and tell people all about the Miracle of the Forest,For more information, write: Forest for Us, P. O. Box 2000,Washington, DC 20223Miracle of the ForestIn addition to many other things, the National Forests have provided (46) ______ for the building of houses, and (47)______for the railroad. The National Forests have renewed themselves because of (48)______ and so they are now called (49)______ . This advertisement invites readers to join in the program of (50)______ .(46)12、(47)13、(48)14、(49)15、(50)16、Task 4Directions: The following is a list of terms. After reading it, you are required to find the items equivalent to those given in Chinese in the table below. Than you should put the corresponding letters in the brackets of question NO. 51-55.()显示编辑资料()关闭其次个编辑窗口17、()选择你想打印的文本 ()删除当前选项18、()选择电源管理模式 ()以只读模式打开文件19、()移动光标到当前行的开关()给—个已存在的文件重命名20、()显示隐蔽文件()给当前文件选择一个路径名21、Task 5Directions: The following is a passage. After reading the passage you should give brief answers to the 5 questions (No.56 through No.60) following them.A Job Wanted AdCASTLE HOTELAssistant ManagerWe are looking for an enthusiastic person to assist in the expansion of the hotel.The successful applicant(申请人)will have experience of overall hotel work and at least one year's experience as an AssistantManager.Applicants need good knowledge of English and possibly two other languages.Good salary, bonus(奖金) , good holidays and excellent prospects for promotion(晋升) within the group.Apply in confidence with a full resume and a recent photograph to:Mr. Gerry Bateman, Castle Hotel, Green Street, Barton BR77QT An Application Letter136 Brownless RoadCatford.PL4 2EBAugust 19, 2000Dear Mr. Bateman,I saw your advertisement for an Assistant Manager in this week's issue of The Hotelier and I should like to apply for the position.I am enclosing my resume and a recent photograph.As you see I have been Assistant Manager at the Granada Hotel in Madrid for a year and I would very much like to have experience of hotel work in England.I am at present on holiday in England and staying with friends at the above address. I shall be returning to Spain at the end of the month.Yours sincerely,Maria SanchezWhere did the applicant find the advertisement?In ____________________ of The Hotelier.22、What other experience should the applicants have besides being an Assistant Manager?They should have experience of____________________.23、What are the applicants required to send to Mr. Gerry Bateman?A full resume and ___________________ .24、What is Mari a Sanehez’s present job?She is_____________________ .25、What is Maria Sanchez doing in England now?She is____________________ there .四、Translation from English to Chinese1、 Had she found the right buyer, she would have sold the house.A.只有找到了正式的买方，她才能售出房屋。
学术英语(理工)详解答案_Unit 2
highlighted texts such as words in bold or italic text;
graphs, tables or diagrams.
Unit 2 Searching for Information
2 Scanning and skimming
1 What does “A.I.” in the title stand for? Artificial intelligence. 2 What is the main idea of the article you may predict from the title? The article may argue for/again the idea that Artificial intelligence will replace human jobs in the future. 3 What does the story in the first paragraph imply? The story tells that computerization threatens to replace
To evaluate source materials
Is the material a primary or a secondary source? Is the source the latest one? Is the author a reliable scholar or an expert in the field? Does the author have biases or prejudices? Has the author been cited frequently in the field? Are the author’s arguments supported by evidence such as statistics, experiment, recent scientific findings? Are different opinions considered and weighed or simply ignored ? Are the author’s arguments and conclusions convincing?
Melp600_MILCOM 2001
A 600 BPS MELP VOCODER FOR USE ON HF CHANNELSMark W. ChamberlainHarris Corporation, RF Communications Division1680 University Avenue Rochester, New York 14610ABSTRACTThe U.S. government has developed and adopted a new Military Standard vocoder (MIL-STD-3005) algorithm called Mixed Excitation Linear Prediction (MELP) which operates at 2.4Kbps. The vocoder has good voice quality under benign error channels. However, when the vocoder is subjected to a HF channel with typical power output of a ManPack Radio (MPR), the vocoder speech quality is severely degraded. Harris has found that a 600 bps vocoder provides significant increase in secure voice availability relative to the 2.4Kbps vocoder. This paper describes a 600 bps MELP vocoder algorithm that takes advantage of the inherent inter-frame redundancy of the MELP parameters. Data is presented showing the advantage in both Diagnostic Acceptability Measure (DAM) and Diagnostic Rhyme Test (DRT) with respect to SNR on a typical HF Channel when using the vocoder with a MIL-STD-188-110B [1] waveform.INTRODUCTIONA need exists for a low rate speech vocoder with the same or better speech quality and intelligibility as the current performance of 2.4Kbps Linear Predictive Coding (LPC10e) based systems. A MELP speech vocoder at 600 bps would take advantage of robust lower bit-rate waveforms than the current 2.4Kbps LPC10e standard and benefit from better speech quality of the MELP vocoder parametric model. Tactical ManPack Radios (MPR) require lower bit-rate waveforms to ensure 24-hour connectivity using digital voice. Once H F users receive reliable good quality digital voice, wide acceptance will provide for better security by all users. HF user will also benefit from the inherent digital squelch of digital voice and the elimination of atmospheric noise in the receive audio.The LPC10e vocoder has been widely used as part of NATO’s and the US DoD’s encrypted voice systems in use on H F channels. The 2.4Kbps system allows for communication on narrow-band H F channels with only limited success. The typical 3 kH z channel requires a relatively high SNR to allow reliable secure communications at the standard 2.4Kbps bit rate. The useof MIL-STD-188-110B waveforms at 2400bps would still require a 3 kH z SNR of more than +12 dB to provide a usable communication link over a typical fading channel.When H F channels do allow a 2400 bps channel to be relatively error free, the voice quality of LPC10e is still marginal. Speech intelligibility and acceptability of LPC10e is limited to the amount of background noise level at the microphone. The intelligibility is further degraded by the low-end frequency response of the military H-250 handset. The MELP speech model has an integrated noise pre-processor as described in [2] that improves the vocoder’s sensitivity to both background noise and low-end frequency roll-off. The 600 bps MELP vocoder would benefit from the noise pre-processor and the improved low-end frequency insensitivity of the MELP model.The proposed 600 bps system discussed in this paper consists of a conventional MELP vocoder front end, a block buffer for accumulating multiple frames of MELP parameters, and individual block Vector Quantizers for MELP parameters. The low-rate implementation of MELP uses a 25 ms frame length and the block buffer of four frames, for block duration of 100ms. The MELP parameters are coded as shown in Table 1. This yields a total of sixty bits per block of duration 100 ms, or 600 bits per second.Details of the individual parameter coding methods are covered below, followed by a comparison of bit-error performance of a Vector Quantized 600 bps LPC10e based vocoder contrasted against the proposed MELP 600 bps vocoder. We will discuss Diagnostic Rhyme Test (DRT) and the Diagnostic Acceptability Measure (DAM) resultsfor MELP 2400 and 600 for several different conditions,SPEECH PARAMETERS BITS Aperiodic Flag 0 Band-Pass Voicing 4Energy 11 Fourier Magnitudes 0Pitch 7 Spectrum (10+10+9+9)Table 1 - MELP 600 VOCODERand compare them with the results for LPC10e based systems under similar conditions. DRT and DAM results represent testing perform by H arris and the National Security Agency (NSA). H arris performed tests shall be identified by a superscript value 1 and NSA data shall be identified by a superscript value 2.LPC SPEECH MODELLPC10e has become popular because it preserves nearly all of the intelligibility information, and because the parameters can be closely related to human speech production of the vocal tract. LPC10e as defined in [3] represents the speech spectrum in the time domain rather than in the frequency domain. The LPC10e Analysis process (transmit side) produces predictor coefficients that model the human vocal tract filter as a linear combination of the previous speech samples. These predictor coefficients are transformed into reflection coefficients to allow for better quantization, interpolation, and stability evaluation and correction. The synthesized output speech from LPC10e is a gain scaled convolution of these predictor coefficients with either a canned glottal pulse repeated at the estimated pitch rate for voiced speech segments, or convolution with random noise representing unvoiced speech.The LPC10e speech model then consists of two half frame voicing decisions, an estimate of the current 22.5 ms frames pitch rate, the RMS energy of the frame, and the short-time spectrum represented by a 10th order prediction filter. A small portion of the more important bits of a frame are then coded with a simple hamming code to allow for some degree of tolerance to bit errors. During unvoiced frames, more bits are free and are used to protect more of the frame from channel errors.The simple LPC10e model does generate a high degree of intelligibility. H owever, the speech can sound very synthetic and often contains buzzing speech. Vector Quantizing of this model to lower rates then would still contain the same synthetic sounding speech. The synthetic speech usually only degrades as the rate is reduced. A vocoder that is based on the MELP speech model may offer better sounding quality speech than one based on LPC10e. The remaining portion of the paper investigates the vector quantization of the MELP model.MELP SPEECH MODELMELP was developed by the U.S. government DoD Digital Voice Processing Consortium (DDVPC) [4] as the next standard for narrow band secure voice coding. The new speech model represents a dramatic improvement in speech quality and intelligibility at the 2.4Kbps data rate. The algorithm performs well in harsh acoustic noise such as HMMWV’s, helicopters and tanks. The buzzy sounding speech of LPC10e model has been reduced to an acceptable level. The MELP model represents the next generation of speech processing in bandwidth constrained channels.The MELP model as defined in MIL-STD-3005 [5] is based on the traditional LPC10e parametric model, but also includes five additional features. These are mixed-excitation, aperiodic pulses, pulse dispersion, adaptive spectral enhancement, and Fourier magnitudes scaling of the voiced excitation.The mixed-excitation is implemented using a five band-mixing model. The model can simulate frequency dependent voicing strengths using a fixed filter bank. The primary effect of this multi-band mixed excitation is to reduce the buzz usually associated with LPC10e vocoders. Speech is often a composite of both voiced and unvoiced signals. MELP performs a better approximation of the composite signal than LPC10e’s Boolean voiced/unvoiced decision.The MELP vocoder can synthesize voiced speech using either periodic or aperiodic pulses. Aperiodic pulses are most often used during transition regions between voiced and unvoiced segments of the speech signal. This feature allows the synthesizer to reproduce erratic glottal pulses without introducing tonal noise.Pulse dispersion is implemented using a fixed pulse dispersion filter based on a spectrally flattened triangle pulse. The filter is implemented as a fixed finite impulse response (FIR) filter. The filter has the effect of spreading the excitation energy within a pitch period. The pulse dispersion filter aims to produce a better match between original and synthetic speech in regions without a formant by having the signal decay more slowly between pitch pulses. The filter reduces the harsh quality of the synthetic speech.The adaptive spectral enhancement filter is based on the poles of the LPC vocal tract filter and is used to enhance the formant structure in the synthetic speech. The filter improves the match between synthetic and natural bandpass waveforms, and introduces a more natural quality to the output speech.The first ten Fourier magnitudes are obtained by locating the peaks in the FFT of the LPC residual signal. The information embodied in these coefficients improves the accuracy of the speech production model at the perceptually important lower frequencies. The magnitudes are used to scale the voiced excitation to restore some of the energy lost in the 10th order LPC process. This increases the perceived quality of the coded speech, particularly for males and in the presence of background noise.MELP 2400 PARAMETER ENTROPYThe entropy values shown below give interesting insight into the existing redundancy in the MELP vocoder speech model. MELP’s entropy is shown in Table 2 below. The entropy in bits was measured using the TIMIT speech database of phonetically balanced sentences that was developed by the Massachusetts Institute of Technology (MIT), SRI International, and Texas Instruments (TI). TIMIT contains speech from 630 speakers from eight major dialects of American English, each speaking ten phonetically rich sentences. The entropy of successive number of frames was also investigated to determine good choices of block length for block quantization at 600 bps. The block length chosen for each parameter is discussed in the following sections.Vector quantization is the process of grouping source outputs together and encoding them as a single block. The block of source values can be viewed as a vector, hence the name vector quantization. The input source vector is then compared to a set of reference vectors called a codebook. The vector that minimizes some suitable distortion measure is selected as the quantized vector. The rate reduction occurs as the result of sending the codebook index instead of the quantized reference vector over the channel. The vector quantization of speech parameters has been a widely studied topic in current research. At low rate of quantization, efficient quantization of the parameters using as few bits as possible is essential. Using suitable codebook structure, both the memory and computational complexity can be reduced. One attractive codebook structure is the use of a multi-stage codebook as described in [6]. In addition, the codebook structure can be selected to minimize the effects of the codebook index to bit errors. The codebooks presented in this paper are designed using the generalized Lloyd algorithm to minimize average weighted mean-squared error using the TIMIT speech database as training vectors. The generalized Lloyd algorithm consists of iteratively partitioning the training set into decisions regions for a given set of centroids. New centroids are then re-optimized to minimize the distortion over a particular decision region. The generalized Lloyd algorithm is reproduced here from reference [7].1. Start with an initial set of codebook values {Y i (0)}i=1,Mand a set of training vectors {X n}n=1,N. Set k = 0, D(0)=0. Select a threshold ε.2. The quantization region {V i(k)}i=1,M} are given byV i(k) = {X n:d(X n,Y i) < d(X n,Y j) ∀ j ≠ i} i = 1,2,…,M. 3. Compute the average distortion D(k) between thetraining vectors and the representative codebook value.4. If (D(k)-D(k-1))/D(k) < ε, stop; otherwise, continue.5. k=k+1. Find new codebook values {Y i(k)}i=1,M that arethe average value of the elements of each quantization regions V i(k-1). Go to step 2.APERIODIC QUANTIZATIONThe aperiodic pulses are designed to remove the LPC synthesis artifacts of short, isolated tones in the reconstructed speech. This occurs mainly in areas of marginally voiced speech, when reconstructed speech is purely periodic. The aperiodic flag indicates a jittery voiced state is present in the frame of speech. When voicing is jittery, the pulse positions of the excitation are randomized during synthesis based on a uniform distribution around the purely periodic mean position. Investigation of the run-length of the aperiodic state indicates that the run-length is normally less than three frames across the TIMIT speech database and over several noise conditions tested. Further, if a run of aperiodic voiced frames does occur, it is unlikely that a second run will occur within the same block of four frames. It was decided not to send the Aperiodic bit over the channelsince the effects on voice quality was not as significant as quantizing the remaining MELP parameters better.BANDPASS VOICING QUANTIZATIONThe band-pass voicing (BPV) strengths control which of the five bands of excitation are voiced or unvoiced in the MELP model. The MELP standard sends the upper four bits individually while the least significant bit is encoded along with the pitch. Table 3 illustrates the probability density function of the five bandpass voicing bits. These five bits can be easily quantized down to only two bits with very little audible distortion. Further reduction can be obtained by taking advantage of the frame-to-frame redundancy of the voicing decisions. The current low-rate coder uses a four-bit codebook to quantize the most probable voicing transitions that occur over a four-frame block. A rate reduction from four frames of five bit band-pass voicing strengths is reduced to only four bits. At four bits, some audible differences are heard in the quantized speech. H owever, the distortion caused by the band-pass voicing is not offensive.ENERGY QUANTIZATIONMELP’s energy parameter exhibits considerable frame-to-frame redundancy, which can be exploited by various block quantization techniques. A sequence of energy values from successive frames can be grouped to form vectors of any dimension. In the MELP 600 bps model, we have chosen a vector length of four frames of two gain values per frame. The energy codebook was created using the K-means vector quantization algorithm and is described in [7]. The codebook were trained using training data scaled by multiple levels to prevent sensitivity to speech input level. During the codebook training process, a new block of four energy values are created for every new frame so that energy transitions are represented in each of the four possible location within the block. The resulting codebook is searched resulting in a codebook vector that minimizes mean squared error. For MELP 2400, two individual gain values are transmitted every frame period. The first gain value is quantized to five bits using a 32-level uniform quantizer ranging from 10.0 to 77.0 dB. The second gain value is quantized to three bits using an adaptive algorithm that is described in [5]. In the MELP 600 bps model, we have vector quantized both of MELP’s gain values across four frames. Using the 2048 element codebook, we reduce the energy bits / frame from 8 bits per frame for MELP 2400 down to 2.909 bits per frame for MELP 600. Quantization values below 2.909 bits per frame for energy were investigated, but the quantization distortion becomes audible in the synthesized output speech and effected intelligibility at the onset and offset of words.FOURIER MAGNITUDES QUANTIZATIONThe excitation information is augmented by including Fourier coefficients of the LPC residual signal. These coefficients or magnitudes account for the spectral shape of the excitation not modeled by the LPC parameters. These Fourier magnitudes are estimated using a FFT on the LPC residual signal. The FFT is sampled at harmonics of the pitch frequency. In the current MIL-STD-3005, the lower ten harmonics are considered more important and are coded using an eight-bit vector quantizer over the 22.5 ms frame.The Fourier magnitude vector is quantized to one of two vectors. For unvoiced frames, a spectrally flat vector is selected to represent the transmitted Fourier magnitude. For voiced frames, a single vector is used to represent all voiced frames. The voiced frame vector was selected to reduce some of the harshness remaining in the lowrate vocoder. The reduction in rate for the remaining MELP parameters reduce the effect seen at the higher data rates to Fourier magnitudes. No bits are required to perform the above quantization.PITCH QUANTIZATIONThe MELP model estimates the pitch of a frame using energy normalized correlation of 1kH z low-pass filtered speech. The MELP model further refines the pitch by interpolating fractional pitch values as described in [5]. The refined fractional pitch values are then checked for pitch errors resulting from multiples of the actual pitch value. It is this final pitch value that the MELP 600 vocoder uses to vector quantize.MELP’s final pitch value is first median filter (order 3) such that some of the transients are smoothed to allow thelow rate representation of the pitch contour to sound more natural. Four successive frames of the smoothed pitch values are vector quantized using a codebook with 128 elements. The codebook was trained using the k-means method as described in [7]. The resulting codebook is searched resulting in the vector that minimizes mean squared error of voiced frames of pitch.SPECTRUM QUANTIZATIONLPC spectrum of MELP is converted to line spectral frequencies (LSFs) [8] which is one of the more popular compact representations of the LPC spectrum. The LSF’s are quantized with a four-stage vector quantization algorithm [9]. The first stage has seven bits, while the remaining three stages use six bits each. The resulting quantized vector is the sum of the vectors from each of the four stages and the average vector. At each stage in the search process, the VQ search locates the “M best” closest matches to the original using a perceptual weighted Euclidean distance [5]. These M best vectors are used in the search for the next stage. The indices of the final best at each of the four stages determine the final quantized LSF.The low-rate quantization of the spectrum quantizes four frames of LSFs in sequence using a four-stage vector quantization process. The first two stages of codebook uses ten bits, while the remaining two stages uses nine bits each. The search for the best vector uses a similar “M best” technique with perceptual weighting as is used for the MIL-STD-3005 vocoder. Four frames of spectra are quantized to only 38 bits.The codebook generation process uses both the K-Means and the generalized Lloyd technique. The K-Means codebook is used as the input to the generalized Lloyd process. A sliding window was used on a selective set of training speech to allow spectral transitions across the four-frame block to be properly represented in the final codebook. It is important to note that the process of training the codebook requires significant diligence in selecting the correct balance of input speech content. The selection of training data was created by repeatedly generating codebooks and logging vectors with above average distortion. This process removes low probability transitions and some stationary frames that can be represented with transition frames without increasing the over-all distortion beyond unacceptable levels.DAM / DRT PERFORMANCEThe Diagnostic Acceptability Measure (DAM) [10] and the Diagnostic Rhyme Test (DRT) [11] are used to compare the performance of the MELP vocoder to the existing LPC based system. Both tests have been used extensively by the US government to quantify voice coder performance. The DAM requires the listeners to judge the detectability of a diversity of elementary and complex perceptual qualities of the signal itself, and of the background environment. While the DRT is a two choice intelligibility test based upon the principle that the intelligibility relevant information in speech is carried by a small number of distinctive features. The DRT was designed to measure how well information as to the state of six binary distinctive features (voicing, nasality, sustension, sibiliation, graveness, and compactness) have been preserved by the communications system under test. The DRT performance of both MELP based vocoders exceeds the intelligibility of the LPC vocoders for most test conditions. The 600bps MELP DRT is within just 3.5 points of the higher bit-rate MELP system. The rate reduction by vector quantization of MELP has not effected the intelligibility of the model noticeably. The DRT scores for HMMWV demonstrate that the noise pre-processor of the MELP vocoders enables better intelligibility in the presence of acoustic noise.the strength of the new speech model. MELP’s speech acceptability at 600 bps is more than 4.9 points better thanLPC10e 2400 in the quiet test condition, which is the most noticeable difference between both vocoders. Speaker recognition of MELP 2400 is much better than LPC10e 2400. MELP based vocoders have significantly lesssynthetic sounding voice with much less buzz. Audio of MELP is perceived to being brighter and having more low-end and high-end energy as compared to LPC10e.SECURE VOICE AVALIBILITYSecure voice availability is directly related to the bit-error rate performance of the waveform used to transfer the vocoder’s data and the tolerance of the vocoder to bit-errors. A 1% bit-error rate causes both MELP and LPC based coders to degrade voice intelligibility and quality as seen in table 5. The useful range therefore is below approximately a 3% bit-error rate for MELP and 1% for LPC based vocoders.The 1% bit-error rate of the MIL-STD-188-110B waveforms can be seen for both a Gaussian and CCIR Poor channels in figures 1 and figure 2, respectively. The curves indicate a gain of approximately seven dB can be achieved by using the 600 bps waveform over the 2400bps standard. It is in this lower region in SNR that allows HF links to be functional for a longer portion of the day. In fact, many 2400 bps links cannot function below a 1% bit-error rate at any time during the day based on propagation and power levels. Typical ManPack Radios using 10-20W power levels make the choice in vocoder rate even more mission critical.HARDWARE IMPLEMENTATIONThe MELP vocoder discussed in this paper runs real-time on a sixteen bit fixed-point Texas Instrument’s TMS320VC5416 digital signal processor. The low-power hardware design resides in the RF-5800H/PRC-150 ManPack Radio and is responsible for running several voice coders and a variety of data related interfaces and protocols. The DSP hardware design runs the on-chip core at 150MH z (zero wait-state) while the off-chip accesses are limited to 50 MHz (two wait-state). The data memory architecture has 64K zero wait-state on chip memory and 256K of two wait-state external memory which is paged in 32 K banks. For program memory, we have an additional 64K zero wait-state on chip memory and 256K of external memory that is fully addressed by the DSP.The 2400 bps MELP source code was developed by NSA, Microsoft, ASPI, Texas Instruments, and ATT. The source code consists of TI’s 54X assembly language source code combined with Harris’s MELP 600 vocoder. This code has been modified to run on the TMS320VC5416 architecture using the FAR CALLING run-time environment, which allows DSP programs to span more than 64K. The code has been integrated into a C calling environment using TI’s C initialize mechanism to initialize MELP’s variables and combined with a H arris proprietary DSP operating system.Run-time loading on the MELP 2400 target system allows for Analysis to run at 24.4 % loaded, the Noise Pre-Processor is 12.44% loaded, and Synthesis to run at 8.88 % loaded. Very little load increase occurs as part of MELP 600 Synthesis since the process is no more than a table lookup. The additional cycles for MELP 600 vocoderis contained in the vector quantization of the spectrum in Analysis.CONCLUSIONSThe speech quality of the new MIL-STD-3005 vocoder is indeed much better than the old FED-STD-1015 [3] vocoder. This paper has investigated the use of Vector Quantization techniques on the new standard vocoder combined with the use of the 600 bps waveform as is defined in U.S. MIL-STD-188-110B. The results seem to indicate that a 5-7 dB improvement in HF performance is possible on some fading channels. Furthermore, the speech quality of the 600 bps vocoder is better than the existing 2400 bps LPC10e standard for several test conditions. However, on air testing is required to validate the simulation results presented. If the on air tests confirm the results presented in this paper, low-rate coding of MELP should be considered to be added to the MIL-STD-3005 for improved communication and extended availability to ManPack radios on difficult HF links.ACKNOWLEDGMENTSThe author wishes to acknowledge the contributions of John Collura of the National Security Agency and to all participating members of the U.S. government’s DoD Digital Voice Processing Consortium (DDVPC), in their efforts to create the 2.4Kbps Mixed Excitation Linear Prediction (MELP) voice coding algorithm standard.REFERENCES(1) MIL-STD-188-110B – “Mil. Std. Interoperability andPerformance Standards for Data Modems”, Draft Version Revised 7 March 2000(2) Collura, John S., “Noise Pre-Processing for TacticalSecure Voice Communications.” IEEE Speech Coding Workshop-99, Porvoo Finland(3) “Analog to Digital Conversion of Voice by 2400bits/second Linear Predictive Coding”, Federal Standard 1015, Nov 1984(4) Supplee Lynn M., Cohn Ronald P., Collura John S.,McCree Alan V., ”MELP: The New Federal Standard at 2400 bps”, IEEE ICASSP-97 Conference, Munich Germany(5) “Analog-to-Digital Conversion of voice by 2400bit/second Mixed Excitation Linear Prediction (MELP)”, MIL-STD-3005, Dec 1999(6) Gersho A., Gray R. M., Vector Quantization andSignal Compression, Norwell, MA:Kluwer Academic Publishers, 1991 (7) Linde Y., Buzzo A., Gray R. M., “An Algorithm forVector Quantization Design”, IEEE Transactions on Communications, COM-28:84-95, Jan 1980(8) Soong F., Juang B., ”Line Spectrum Pairs (LSP) andSpeech Compression”, IEEE Int. Conf. On Acoustics, Speech, and Signal Processing, 1983(9) Juang B. –H., Gray A. H. Jr., “Multiple Stage VectorQuantization for Speech Coding”, In International Conference on Acoustics, Speech, and Signal Processing, volume 1, pages 597-600, Paris France, April 1982(10) Voiers William D., “Diagnostic AcceptabilityMeasure (DAM): A Method for Measuring the Acceptability of Speech over Communications Systems”, Dynastat, Inc.; Austin Texas(11) Voiers William D., ”Diagnostic Evaluation of SpeechIntelligibility.”, In M.E.Hawley, Ed, Speech Intelligibility and Speaker Recognition (Dowder,Huchinson, and Ross; Stroudsburg, PA 1977)。
费列罗的经典广告词（1篇）
费列罗的经典广告词(1篇)以下是网友分享的关于费列罗的经典广告词的资料1篇，希望对您有所帮助，就爱阅读感谢您的支持。
篇一经典的slogan 广告词1．Good to the last drop．滴滴香浓，意犹未尽。
（麦斯威尔咖啡）2．Obey your thirst．服从你的渴望。
（雪碧）3．The new digital era．数码新时代。
（索尼影碟机）4．We lead. Others copy．我们领先，他人仿效。
（理光复印机）5．Impossible made possible．使不可能变为可能。
（佳能打印机）6．T ake time to indulge．尽情享受吧！（雀巢冰激凌）7．The relentless pursuit of perfection．不懈追求完美。
（凌志轿车）8．Poetry in motion, dancing close to me．动态的诗，向我舞近。
（丰田汽车）9．Come to where the flavor is. Marlboro Country．光临风韵之境，万宝路世界。
（万宝路香烟）10．T o me, the past is black and white, but the future is always color．对我而言，过去平淡无奇；而未来，却是绚烂缤纷。
（轩尼诗酒）11. Just do it. 只管去做。
（耐克运动鞋）12. Ask for more. 渴望无限。
（百事流行鞋）13. The taste is great. 味道好极了。
（雀巢咖啡）14. Feel the new space. 感受新境界。
（三星电子）15. Intelligence everywhere.智慧演绎，无处不在。
（摩托罗拉手机）16. The choice of a new generation.新一代的选择。
（百事可乐）17. We integrate, you communicate.我们集大成，您超越自我。
考试失利然后反思经历英语作文
考试失利然后反思经历英语作文Reflection on a Failed ExamExams are an integral part of the academic journey, and they serve as a crucial measure of our knowledge and understanding. They challenge us to demonstrate our abilities, push our limits, and strive for excellence. However, sometimes, despite our best efforts, we face the disappointment of failing an exam. In my case, this experience was a pivotal moment that led to a profound reflection on my approach to learning and personal growth.The day I received my exam results was a mixture of disbelief and self-doubt. I had prepared diligently, spent countless hours studying, and was confident in my abilities. Yet, the scores did not reflect the effort I had put in. As I sat there, staring at the numbers, I couldn't help but feel a sense of failure and disappointment wash over me. It was a humbling experience, one that forced me to confront my own limitations and shortcomings.In the aftermath of the failed exam, I found myself grappling with a range of emotions. Anger and frustration were initial reactions, as I questioned the fairness of the assessment and the validity of theresults. However, as the initial shock subsided, I realized that dwelling on these negative emotions would only hinder my ability to learn from the experience.Determined to move forward, I embarked on a journey of self-reflection. I started by carefully analyzing my study habits, the way I approached the material, and the strategies I employed during the exam. I recognized that my preparation, while extensive, lacked the depth and focus required to truly master the subject matter. I had been relying too heavily on memorization and surface-level understanding, rather than developing a deeper, more comprehensive grasp of the concepts.This realization was pivotal, as it led me to reevaluate my approach to learning. I recognized the importance of not just memorizing facts and formulas, but truly understanding the underlying principles and their practical applications. I made a conscious effort to shift my mindset from simply passing exams to truly engaging with the material and cultivating a genuine interest in the subject.Furthermore, I acknowledged the role that my personal limitations and weaknesses played in my performance. I identified areas where I struggled, such as time management, test-taking strategies, and the ability to effectively communicate my knowledge. Recognizing these shortcomings was the first step in addressing them.With a renewed sense of purpose, I set out to implement a more comprehensive and strategic study plan. I started by breaking down the subject matter into manageable chunks, focusing on one concept at a time and ensuring a solid foundation before moving on. I also incorporated active learning techniques, such as practice problems, group discussions, and real-world applications, to deepen my understanding.Additionally, I sought out support from my professors, tutors, and peers. I was not afraid to ask for help or clarification when I encountered difficulties, understanding that seeking guidance is a sign of strength, not weakness. Through these collaborative efforts, I gained new perspectives and valuable insights that enriched my learning experience.As I progressed through this process of reflection and self-improvement, I began to see tangible results. My subsequent exam performance improved significantly, and I found that I was not only able to achieve better grades but also develop a genuine passion for the subject matter. The sense of accomplishment that came with this transformation was immensely rewarding, and it reinforced my belief in the power of resilience and determination.The experience of failing an exam, while initially difficult, ultimatelyserved as a catalyst for my personal growth and academic development. It taught me the importance of adaptability, humility, and a willingness to embrace challenges as opportunities for learning and improvement. By reflecting on my shortcomings and taking proactive steps to address them, I was able to transform a seemingly negative experience into a positive and transformative one.Today, I look back on that failed exam with a sense of gratitude, as it has shaped me into a more thoughtful, resilient, and dedicated student. The lessons I learned have not only benefited my academic pursuits but have also equipped me with valuable skills and mindsets that I can apply to various aspects of my life. This experience has reinforced my belief that failure is not the end, but rather the beginning of a journey towards greater growth and success.。
(日记)补课英语日记范文
补课英语日记范文相信很多同学都有补课的经历。
那么关于补课的英语作文有哪些呢下面是学习啦我推荐给大家的关于补课的英语作文，供大家参考。
补课英语日记1Parents, especially those of teenagers, care about their children’s education more than anything else. They could do everything for their children. Many of them spend most of their spare time coaching their children in studies; those who have time or cannot do it have hired tutors. Some also send children to after-class schools. Some even have tried to mould their home environment more favorable for study. It seems as if a better education is all that parents expect for children.The present situation can be explained by the following reasons. First of all, as our country’s economy moves ahead healthily, many parents have become aware that future success depends more and more on skills and education. Lack of training and education will no longer ensure young people to have a promising future. Secondly, it is evident that in a competitive society there are both losers and winners. The better skills and knowledge children possess, the more opportunities they will be ensures. What is more, with school tuitions increasing it is also reasonable for parents to expect their children to be somebody or dosomething great as a result of education they have received. Certainly, it is good to see much of parents’ attention on children’s education. However, in my opinion, emphasis should also be laid on fostering other abilities and personal qualities. True, it is important to learn to succeed, but the first thing to learn is how to survive and how to be a qualified citizen. If this is included in good education that parents are seeking now, their children will be definitely ensured not only of a bright future but also a sound intellectual and mental foundation, hence a healthy life.补课英语日记2It is nothing new that many students go to take after-school classes now, but in my opinion, it’s just a waste of time and money. When I was in primary school, my parents sent me to different kinds of these classes, too. But later I realized I didn’t want to do that anymore. I began to spend more time on reading, doing sports and taking social activities. However, I didn’t fall behind any others in study.If I have time, I will play basketball with my friends. It’s a wise way to stay in good health. I really enjoy it. Through playing basketball, I know how to cooperate with others, and I make a lot of friends, too. What’s more, I become stronger and taller. I have benefited a lot from it. And now I become more creative and confident than those who are always involved in taking after-school classes. I think students should spendmore time on doing the things they like instead of going to after-school classes, thus we can live happier.补课英语日记3In order to know what the students ideas are to the question of making-up lessons during weekends(holiday) a certain students’ union did investigations on it.Finally it got the following results. Some students go along with the measure. They think the measure have some good points.For example the measure can be give less time to play for students and let students to review knowledge that can help them give more grades. But the measure will make teachers feel tired.However other students don’t go along with the measure. They think the measure is only a tactical fatigue which goes against allocation of time and will wasted time.They also think it will add to the burden and it is bad for development of the personality of students.补课英语日记4It seems that many students go to take after-school classes but it is just a waste of time and money. I used to go to different kinds of these classes too.But later I realized I couldnt do that any more. I began to spend more time reading doing sports and taking some social activities.Meanwhile I didnt fall behind others in study.I prefer to have time to enjoy the nature. Its a wise way to know about the world. So I often put my spare time to good use by watching animals plants rocks .Around my city. I still remember that day I went to the Forest Park this spring! And I found a few plants appearing in my biology books.It offered me an opportunity to deepen my understanding of my textbooks.Learning by using is a real practice. I have benefited a lot from it. Now I am becoming more creative and confident than those who are always involved in taking after-school classes.补课英语日记5On Saturday morning, we went to Miss Lius house at 7:20 to wait for the bus. We waited at Miss Lius house for a while. Well get on the bus. We talked about the beautiful scenery while enjoying it in the car. Soon we arrived at the place where we made up the lessons. We took our books upstairs.We had a rest when we got upstairs. We were going to have class. The teacher drew four figures for us. The teacher said, the answer to the Chinese question is not unique. Ill have lunch soon. After lunch, we have English class. Well go home at three oclock.补课英语日记6Make up a missed lesson is many students choose to ascend grades of important ways is also the commonly used method can make up a missed lesson learned knowledge to review deepen prevent forgotten. If excellent students make up a missed lesson can assure result not to drop more and more outstanding; For bad grades for students it can ascend results is that many parents and students performance enhancing primary choice.At the same time make up a missed lesson also exists some bad influence.Students for ascension results spend most of my time spent on make-up often do not and extracurricular knowledge contact cause for the final in-class knowledge skilled for extracurricular practice unfamiliar and make up a missed lesson will also give students at school at ordinary times the pressure for example after-school also spent in study energy to students only the correct understanding of the advantages and disadvantages of make-up make enough psychological preparation and is willing to make up missed lesson so that make up a missed lesson can play its real effect.补课英语日记7Summer vacation came.I thought I could have a rest after this semester’s hard work.But my mom and dad had their plan. They asked a teacher to make uplessons for me.So I had to get up early at 6 o’clock every morning and went a long way to the teachers.After I finished my classes and went home it was already late.I almost had no time to play and even had little time to rest.What a hard time for me!But my mom and dad said to me that if I didn’t work hard now I would be nothing in the future.What can I do then。
国开《商务英语1》形考任务单元自测5答案
国开《商务英语1》形考任务单元自测5答案适用专业及层次：电子商务、工商管理(市场营销方向)、会计学(财务会计方向)、金融(保险方向)、金融(货币银行方向)、金融(金融与财务方向)、物流管理和物业管理专科。
试题及答案题目顺序是随机的，使用查找功能(Ctrl＋F)进行搜索[题目1] ________improve your service, you need to make market surveys so as to know what your customers are thinking and demanding.[答案] In order to[题目2] ________your customers what they need and more than they expect will lead customers to return to you.[答案] Giving[题目3]Every business has its ups and downs, and so________every person.[答案] does[题目4]—Hello, David! I haven’t heard from you for a long time. How have you been recently？—_________________________________.[答案] Not bad, thank you.[题目5]—Hi, Lily, what’s up with Mike？I heard the boss yelling at Mike earlier today.—_________________________________.[答案] It’s said that Mike made a mistake and then tried to cover it up.[题目6]—I bet that Mike wished you had told him that earlier.—_________________________________.[答案] Well, Mike isn’t a fool, he won’t do that again.题目7]I bet that Mike wished you________him that earlier.[答案] had told[题目8]In this way you will stay________in these changing times.[答案] competitive[题目9]It is better to tell someone to get it________.[答案] fixed[题目10]—Oh. But why didn’t he just own up and tell someone？—_________________________________.[答案] He was too scared that he would be fired, I suppose.[题目11]The quality, specifications and prices are________in our contract.[答案] clarified[题目12]The re-examination results indicate that one-third of the goods are not _____ standard. [答案] up to[题目13]We are entitled to cancel it if you fail to_____the contract.[答案] honor[题目14]We try our best to_____your requirement.[答案] meet[题目15]—Your request for compensation made me surprised. What happened？—_________________________________.[答案] It’s because of the quality.二、听力理解：请听下面的对话，根据对话内容从A、B、C三个选项中选出一个最佳选项。
国开大学商务英语1-5答案
国开04009商务英语1任务5参考答案之宇文皓月创作说明：如果课程题目是随机的，请按CTRL+F在题库中逐一搜索每一道题的答案题目1：—Oh. But why didn’t he just own up and tell someone?—: He was too scared that he would be fired, I suppose.; You should have told him that earlier.; So be careful with our job.尺度答案：He was too scared that he would be fired, I suppose.题目2：—I bet that Mike wished you had told him that earlier.—: We should also find what the customers think.; So be careful with our job.; Well, Mike isn’t a fool, he won’t do that again.尺度答案：Well, Mike isn’t a fool, he won’t do that again.题目3：—Hello, David! I haven’t heard from you for a long time. How have you been recently?—: Not bad, thank you.; That’s ok.; Long time no see.尺度答案：Not bad, thank you.题目4：We are entitled to cancel it if you fail to the contract.: honor; sign; draw up尺度答案：honor题目5：improve your service, you need to make market surveys so as to know what your customers are thinking and demanding.: In order that; So as to; In order to尺度答案：In order to题目6：二、阅读理解：阅读下面的对话，选择合适的内容将对话弥补完整。
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ResearchThe Results of Performance Measurements of Field-aged Crystalline Silicon Photovoltaic ModulesArtur Skoczek,Tony Sample*,y and Ewan D.DunlopDG-Joint Research Centre—Institute for Energy,Renewable Energy unit,ItalyThis paper presents the results of electrical performance measurements of204crystalline silicon-wafer based photovoltaic modules following long-term continuous outdoor exposure.The modules comprise a set of 53module types originating from20different producers,all of which were originally characterized at the European Solar Test Installation(ESTI),over the period1982–1986.The modules represent diverse generations of PV technologies,different encapsulation and substrate materials.The modules electrical performance was determined according to the standards IEC60891and the IEC60904series,electrical insulation tests were performed according to the recent IEC61215edition2.Many manufacturers currently give a double power warranty for their products,typically90%of the initial maximum power after10years and80%of the original maximum power after25years.Applying the same criteria(taking into account modules electrical performance only and assuming2Á5%measurement uncertainty of a testing lab)only 17Á6%of modules failed(35modules out of204tested).Remarkably even if we consider the initial warranty period i.e.10%of P max after10years,more than65Á7%of modules exposed for20years exceed this criteria. The definition of life time is a difficult task as there does not yet appear to be afixed catastrophic failure point in module ageing but more of a gradual degradation.Therefore,if a system continues to produce energy which satisfies the user need it has not yet reached its end of life.If we consider this level arbitrarily to be the 80%of initial power then all indications from the measurements and observations made in this paper are that the useful lifetime of solar modules is not limited to the commonly assumed20year.Copyright#2008John Wiley&Sons,Ltd.key words:outdoor tests;qualification tests;long-term degradationReceived23September2008INTRODUCTIONModule lifetime is one of the crucial factors in deter-mining the cost of solar electricity(together with the system price,the annual solar irradiance,and the capital interest rate),which is why lifetime prediction related issues remain a topic of interest of many researchers.The effort to assure high reliability of photovoltaic modules has resulted in the introduction by the International Electrotechnical Commission (IEC)of accelerated test procedures termed‘‘Module Design and Type Approval’’the IEC612151and IEC 61215edition2.2PROGRESS IN PHOTOVOLTAICS:RESEARCH AND APPLICATIONSProg.Photovolt:Res.Appl.2009;17:227–240Published online24December2008in Wiley InterScience()DOI:10.1002/pip.874 *Correspondence to:Tony Sample,DG-Joint Research Centre—Institute for Energy,Renewable Energy unit,Via E.Fermi2749Ispra,Varese21027,Italy.y E-mail:tony.sample@jrc.itCopyright#2008John Wiley&Sons,Ltd.The IEC61215standard‘‘lays down IEC require-ments for the design qualification and type approval of terrestrial photovoltaic modules suitable for long-term operation in general open-air climates,...’’The standard specifies its purpose as‘‘...to determine the electrical and thermal characteristics of the module and to show,as far as is possible within reasonable constraints of cost and time,that the module is capable of withstanding prolonged exposure in climates described in the scope.The actual lifetime expectancy of modules so qualified will depend on their design,their environment,and the conditions under which they are operated...’’A failure according to the IEC61215is deemed to have occurred if the loss in maximum power following a test is greater than5%þthe repeatability of the power measurement of the control module.For a sequence of tests,failure occurs when the cumulative loss exceeds 8%þrepeatability.The other failure modes are major visual defect(such as cracked cells,bubbles or delamination,or loss of mechanical integrity),open-circuit or ground faults detected during or after test execution,andfinally electrical insulation failures. The IEC61215helps manufacturers to assess module lifetime,against a minimum standard,but does not provide an unambiguous value of lifetime, which long-termfield ageing can give.Long-term outdoor exposure in diversified climatic conditions intends to address all failure mechanisms which are difficult or impossible to simulate in the lab during time constrained accelerated tests.Weathering is a continuous process but the magni-tude of the effect will vary due to several factors. Sunlight has one of the greatest effects on outdoor weathering of PV modules and of this the majority of damage is caused by the ultraviolet component of the sunlight.The amount of sunlight is dependent on geo-graphical location and altitude.Geographic location and positioning of the module has a significant effect on it’s weathering resistance.A module in a sunny environment will degrade faster due to increased UV content and elevated temperature.Exposure at elevated altitudes can significantly increase exposure to ultraviolet light and therefore significantly reduce the expected lifetime.Water,falling as rain or as atmospheric humidity,will also have an impact on the weathering resistance.Another factor is air pollution. Its sources may be natural,for example sea salt or dust, or man-made such as soot from exhaust fumes and industrial gases.Sulfur and other pollutants such as acidic fumes which can speed up the degradation process stressing junction boxes,encapsulation material and cause not only the tarnishing of metal frames but also the front glass surface.Also module mounting system has an impact on modules aging. Roof mounted or building integrated modules usually run hotter than free rack-mounted ones. DESCRIPTION OF THEEXPERIMENTThis paper presents the results of electrical perform-ance measurements of204crystalline silicon wafer based photovoltaic modules(53different module types)following long-term continuous outdoor exposure.Between1983and1986the European Solar Test Installation—ESTI laboratory installed(free rack-mounting)various sets of crystalline silicon wafer based photovoltaic modules at the ESTI outdoor field in the Ispra site.The climatic conditions of Ispra (located in northern Italy)at220m above sea level, where the weathering was executed,are considered to be a moderate subtropical climate(À10toþ358C, with less than90%RH).Before outdoor exposure most modules were tested at ESTI lab according to CEC501 test sequence,3or individual parts of the sequence.The basic principles which were later used for the formation of the IEC61215were already applied in this standard,however,the test levels were notably less severe than are applied now.4From the results of the application of the CEC501none of these modules exhibited failure with regard to electrical performance (although two modules failed the electrical insulation test).These modules were then,on completion of the CEC501tests,installed in the ESTI outdoor test site in racks allowing free circulation of air.One group of modules was connected to the grid inverter with the maximum power point tracking circuit,another group was connected to battery charger used occasionally for charging an electric car andfinally the last group was mounted and left at the open circuit conditions.In the mid1990s,all modules were disconnected and left in the open circuit conditions.Before installation,all modules were characterized by measuring their electrical performance,visual inspection,and electrical insulation test.The general measurement principle and equipment used in the1980s and during the latest measurement campaign(2004)is very similar.Modules are measured utilizing the same Large Area Pulse Solar Simulator Spectrolab(LAPSS),which consists of twoCopyright#2008John Wiley&Sons,Ltd.Prog.Photovolt:Res.Appl.2009;17:227–240DOI:10.1002/pip 228 A.SKOCZEK,T.SAMPLE AND E.D.DUNLOPXenon pulseflash tube lamps at a distance of13m from the test plane.The electronic load has a voltage range of1Á0–100V and a current range of0Á1–20A. The shape of SpectroLab LAPSS pulse is trapezoidal with theflat part of the pulse at the set point of1000W/ m2lasting for approximately2ms.In the1980s,the I–V curve data were recorded using dedicated equipment supplied by Spectrolab(8-bit, three channel data acquisition system).Later due to its failure,in the mid1980s,the acquisition system was replaced by a12-bit,four channel Krenz transient recorder and in the2001by the currently used Nicolet INTEGRA20digital oscilloscope with true1M sample/s sampling rate at12-bit signal resolution.The module and the reference cell temperatures are measured with resistance temperature sensors PT-100.The main changes introduced in the operation of the measurement system are the implementation of an improved STC temperature controlÆ0Á58C or better versusÆ28C in the1980s and a new method of digital signalfiltering andfitting of the maximum power point.It should be noted that the reference cell utilized for the comparison of the modules electrical performance has been changed.The original reference cell R301 used20years ago was no longer available;hence all current measurements were performed with the reference cell PX202C.The calibration of the reference cells in the1980s was much more difficult and the uncertainty of the calibration value of the R301 is not available.It was performed by the Royal Aircraft Establishment(RAE)in Cyprus using an outdoor method.Since the idea of the experiment relies on relative measurements,utilization of a different reference cell can be questionable.In order to quantify the potential difference between the reference cells used for these measurements a series of modules which were measured in the1980s and then kept under dark, dry storage conditions for the last20years have been re-measured using the new reference cell PX202C.It is assumed that the stored modules exhibited the same performance(especially modules I SC since FF may be affected by interconnections degradation)in compari-son to their initial state,although it is impossible to preclude their degradation.The results of these measurements are presented in the Table I.The difference in measurements using the two reference cells is small.These results increase the confidence that any changes measured after long-term exposure are the result of aging and not due to change of reference cell.CHARACTERISTICS OF THE MODULESThe main design details of all53different module types(204individual pieces)are presented in Table II. The modules represent various commercially available silicon wafer based technology of the1980s and incor-porate different cell types,encapsulation,and substrateTable parison of measurements performed with two reference cells:R301in the1980s and PX202C in2008oncontrol modules stored in the darkPolycrystalline modulesEsti code IC01GA01GC04MA01Date19862008D[%]19852008D[%]19872008D[%]19852008D[%] V oc[V]22Á3022Á16À0Á6%20Á8320Á890Á30%21Á1020Á97À0Á63%20Á0920Á230Á68% FF[%]71Á0069Á91À1Á5%75Á6075Á38À0Á29%72Á8072Á64À0Á22%75Á2075Á230Á04% P MAX[W]37Á1035Á63À3Á7%43Á3943Á07À0Á73%44Á9044Á35À1Á23%35Á9535Á89À0Á16% I SC[A]2Á342Á30À1Á7%2Á752Á73À0Á62%2Á912Á910Á07%2Á382Á36À0Á87%Monocrystalline modulesEsti code HH01LE01LE04HO02Date19872008D[%]19872008D[%]19882008D[%]19892008D[%] V oc[V]21Á7121Á32À1Á79%21Á6221Á39À1Á06%21Á6621Á27À1Á81%21Á2021Á14À0Á30% FF[%]69Á7269Á41À0Á45%76Á0176Á29À1Á04%75Á5075Á09À0Á55%70Á9071Á010Á16% P MAX[W]41Á4740Á75À1Á72%48Á7747Á54À2Á52%47Á9046Á99À1Á90%43Á0042Á37À1Á47% I SC[A]2Á742Á750Á52%2Á972Á91À2Á02%2Á932Á940Á46%2Á862Á82À1Á30% Copyright#2008John Wiley&Sons,Ltd.Prog.Photovolt:Res.Appl.2009;17:227–240DOI:10.1002/pip FIELD-AGED CRYSTALLINE SILICON PHOTOVOLTAIC MODULES229Table II.Design details of investigated module seriesCode (samples)Cells Strings CelltypeSubstratematerialEncapsulant Totalcellarea[m2]Cell tomodulearea ratioAveragemoduleefficiency[%]P MAX[W]Numberof yearsoutsideAC(6)361Mono—EV A0Á360Á8512Á05220 BA(2)721Mono Silicone Silicone0Á560Á698Á06622D0(8)721Mono Plastic PVB0Á560Á586Á36423 DA(2)331Poly Tedlar,Al PVB0Á330Á758Á53722E0(2)361Mono Glass—0Á280Á636Á83123F0(5)201Poly Glass PVB0Á200Á787Á11823 FA(3)401Poly Glass PVB0Á400Á819Á14023 FD(1)401Poly Glass PVB0Á200Á787Á41923 FF(6)401Poly Glass PVB0Á400Á817Á93920H0(4)726Mono Silicone Silicone0Á560Á666Á15421 HA(6)726Mono Silicone Silicone0Á560Á666Á25520 HB(2)726Poly Tedlar EV A0Á560Á666Á45620 HD(4)401Poly Tedlar EV A0Á400Á847Á23522 HE(4)401Poly Glass EV A0Á400Á847Á63622 HF(2)723Mono Tedlar EV A0Á560Á656Á96022 HG(2)723Poly Tedlar EV A0Á720Á838Á06922 IA(8)361Mono Glass EV A0Á280Á656Á93223 IB(2)361Mono Glass EV A0Á280Á647Á23222 IC(6)401Poly Glass EV A0Á400Á807Á33620J0(4)363Mono Glass Silicone0Á280Á646Á93121 JA(8)361Poly Glass Silicone0Á360Á796Á93121 JB(4)361Mono Glass EV A0Á360Á8110Á54720L0(2)1448Mono Polyester,Al PVB1Á130Á778Á011821 LA(8)1448Mono Polyester,Al PVB1Á130Á777Á911821 LB(8)1448Mono Polyester,Al PVB1Á130Á778Á612421 LD(2)1448Mono Polyester,Al PVB1Á130Á779Á213619M0(4)804Poly Polyethylene EV A0Á400Á858Á43921 MA(6)722Poly Tedlar,Al EV A0Á330Á889Á63621N0(4)721Mono Plastic PVB0Á560Á587Á16823 NA(8)361Poly Tedlar,Al PVB0Á360Á787Á73621 NB(2)361Poly Glass PVB0Á360Á787Á83621 OA(4)361Mono Tedlar,Al EV A0Á280Á647Á43321 OB(4)361Mono Tedlar,Al EV A0Á280Á647Á73420 OC(4)361Mono Tedlar,Al EV A0Á280Á627Á13120 OD(2)341Mono Glass EV A0Á280Á606Á63021 OE(2)361Mono Tedlar EV A0Á280Á637Á53221 OF(1)361Mono Glass EV A0Á280Á637Á33321 OG(2)361Mono Tedlar EV A0Á080Á535Á3821 OH(2)361Mono Glass EV A0Á080Á515Á5921 OI(2)361Poly Tedlar EV A0Á730Á158Á64221 OJ(2)361Mono Tedlar EV A0Á280Á636Á62921 PA(2)361Mono Tedlar,Al PVB0Á440Á718Á95223 QB(2)662Mono Tedlar EV A0Á520Á729Á06423 RA(2)401Poly Silicone Silicone0Á410Á766Á33422 RB(6)361Poly Silicone Silicone0Á180Á706Á91819 SB(2)401Poly——0Á40Á847Á13423 SC(2)401Poly Tedlar EV A0Á40Á8410Á95119 SD(2)361Poly—EV A0Á460Á8410Á35619 UD(2)401Poly Tedlar EV A0Á400Á848Á84219V0(8)361Mono Glass Silicone0Á270Á585Á72820Y0(8)361Mono Tedlar EV A0Á270Á667Á13123 YB(4)381Mono Tedlar EV A0Á290Á708Á73719 YC(4)361Mono Tedlar EV A0Á360Á819Á34119 Copyright#2008John Wiley&Sons,Ltd.Prog.Photovolt:Res.Appl.2009;17:227–240DOI:10.1002/pip 230 A.SKOCZEK,T.SAMPLE AND E.D.DUNLOPmaterials.The majority of modules underwent different types of module qualification tests prior to the continuous outdoor exposure.Modules are rated from about8Wp up to117Wp with average value of around 40Wp.The number of cells varied from20to144cells connected in a configuration of1–8substrings.The material of choice for the front side for all types, similar to modern designs,is hardened/tempered glass. Similarly to contemporary products ethylene-vinyl acetate(EV A)was the most widely used encapsulant for tested modules—29types.However,other types of encapsulants were used,such as polyvinyl butyral (PVB)in14cases and polysiloxanes(silicone)in8 cases.In two cases,the information of the material type is missing.Selection of substrate materials was even more diverse.Like contemporary designs polyvinyl fluoride(tedlar)based foils and combination of tedlar and aluminum foil was the most widely used—21 cases.This was followed by glass—17cases, silicone—5cases,polyester/aluminum4cases,and 1case of polyethylene.Infive cases,the data about the substrate material was not available.Among tested module types,similar numbers of monocrystalline and polycrystalline cells can be found(31and22,respec-tively).Each of the53module types was represented by1–8modules with an average of about four modules. The total exposure time for the different module types varies from19to23years with the average value over21years.The cell packaging density(total active cell area/module area ratio)is lower than for contemporary modules especially for those incorpor-ating monocrystalline round cells,with an average value of0Á66for monocrystalline and0Á77for the polycrystalline modules.Low packaging density results in relatively low average modules efficiency:7Á6%for monocrystalline and8%for polycrystalline modules(11Á4and9Á7%cell efficiency,respectively) considerably lower values to contemporary silicon wafer based modules.MODULES CHARACTERISATION FOLLOWING LONG-TERM OUTDOOR EXPOSUREResults of the electrical performance tests of an initial batch of40modules following long-term outdoor exposed modules at the ESTI site have been already published.4,5Following the initial investigation of the 40modules a further10modules were removed from the outdoorfield(in2004)with the remaining154 modules(in2006).The front surfaces of all of the modules were cleaned and electrical performance tests were conducted according to the IEC608916and the IEC60904series.7–13The modules then underwent a visual inspection and electrical insulation test follow-ing the methods described in the IEC61215edition2.2 The results of these measurements are presented in the following sections.Long-term weathering impact on basic electrical parametersDuring the performance measurements the basic elec-trical parameters:P MAX,I SC,and V OC were deter-mined.Results of the maximum power losses for all module series are presented in the Figures1and2in the form of bar plots.Figure1comprises module series exhibiting average power loss greater than20%. Module series exhibiting smaller average powerlossesFigure1.Relative P MAX losses(module types exhibiting average loss greater than20%)Copyright#2008John Wiley&Sons,Ltd.Prog.Photovolt:Res.Appl.2009;17:227–240DOI:10.1002/pip FIELD-AGED CRYSTALLINE SILICON PHOTOVOLTAIC MODULES231are presented in Figure2.The standard deviations are presented for each series(as dark black lines)giving information on the uniformity of the behavior of each module type(which can be used as an indication of the design and production quality control).The ESTI codes of each series are presented along with the number of modules being tested(in parentheses). The majority of module series exhibit a very coherent behavior of individual modules.As many as39out of the 53types(74%)exhibit the standard deviation of maxi-mum power change below5%.This coherent behavior of individual modules within a given module type is true of both modules with small maximum power loss and modules which suffer significant degradation. Seven module series presented in Figure1(BA(2),FA (3),HE(4),IA(5),OA(4),SD(2),and NA(8))out of the15types(module series with standard deviation of maximum power change greater then5%)exhibit signi-ficantly higher values of standard deviation greater than 15%.Such a large spread of maximum power losses of modules within one series may indicate serious problems with maintaining quality of the production process. Some module series comprise modules with total circuit breakage(IA series three modules out of eight failed,HE series two modules out of four,FA series two modules out of three)and therefore exhibit the highest value of standard deviation.The results also indicate some series where very significant power loss or total circuit failure occurred with consistently poor performance of all modules(E0(2),JB(4),L0(2),OD (2)),which can indicate low quality of the production process or material quality/design problems.The mean calculated power loss of all204modules isÀ17Á3%with the standard deviation of23Á5%.The power loss is a combination of the losses in the V OC,I SC,and FF of the modules.Average losses in other parameters are as follow:I SC:À10Á6%,V OC:À5Á8%, FF:À9Á1%with the standard deviation18Á5,20,and 22%,respectively.In terms of average loss,V OC reveals the smallest values,with the majority of the module series exhibiting little loss of V OC.The significant losses of V OC exhibited only by six series of modules reflect the loss of one or more substrings of the module.Smaller standard deviation in I SC losses indicate higher uniformity in module behavior but the average I SC loss is almost twice as large as the average loss in V OC.The I SC and FF are more strongly affected by module aging processes such as,gradual degradation of semiconductor properties,cell interconnections,and also encapsulant browning.The FF loss is usually attributed to an increase of the series resistance due to the degradation of cell interconnections(such as microscopic cracks).14One of the non-destructive methods used in the investigation of series resistance is IR imaging of the module under forward bias con-ditions with short circuit currentflow.15An example of a thermal image of module NA07with FF loss of 27Á9%can be seen in Figure3.The hot spots visible in the images in Figure3are places of higher resistance caused by contacts degradation,however,the detection of localized heating by thermal imaging does not always indicate significant FF loss.In some cases,hot spots are caused through cell mismatches.The comparison of the I–V curves of two modules D002and NA07exhibiting significant FF loss is shown in the Figure4.The curves plotted with the solid line represent measurements performed in the1980s before long-term outdoor exposure.Dashed lines are the I–V Figure2.Relative P MAX losses(module types exhibiting average loss smaller than20%)Copyright#2008John Wiley&Sons,Ltd.Prog.Photovolt:Res.Appl.2009;17:227–240DOI:10.1002/pip 232 A.SKOCZEK,T.SAMPLE AND E.D.DUNLOPcurves measured in 2006.It can be observed that both modules lost about 9%of short circuit current due to aging process but main power degradation comes from FF loss (43Á7and 28Á9%,respectively).The scatter plots of the P MAX loss dependence on FF and I SC losses are presented in Figures 5and 6.It can be observed in Figure 5that P MAX change is proportional to FF losses especially for high maximum power losses (>20%)which are attributed generally to FF losses (serial resistance increase)with the excep-tion of six modules exhibiting high V OC losses (triangles).The correlation in I SC and P MAX losses presented in Figure 6is not so obvious,although some linear corre-lation is noticeable for moderate modules degradation (I SC losses caused by optical properties degradationlike surface soiling,encapsulant browning,and also light induced doped silicon degradation).15,16The only module type where high power loss (about 40%,marked with black diamonds in Figures 5and 6)is correlated to high short circuit loss is the one exhibiting very strong delamination and encapsulant discoloration (Figure 7).Calculated average annual power degradation The careful evaluation of an annual performance degradation rate relies on periodic electric character-ization of the modules.In the great majority of cases,the modules exposed at Ispra were not periodically checked (some but not representative data exists for individual modules)thus the variation ofannualFigure 3.Thermal image of NA07module under forward bias conditions with short circuit currentflowFigure 4.The I –V curves of two modules measured before and after long-term outdoor exposureCopyright #2008John Wiley &Sons,Ltd.Prog.Photovolt:Res.Appl.2009;17:227–240DOI:10.1002/pipFIELD-AGED CRYSTALLINE SILICON PHOTOVOLTAIC MODULES 233degradation ratio is impossible to obtain.It has been observed by different studies 5,16that the degradation rate is faster at the beginning of the exposure (initial degradation)and then stabilizes at a lower level.For long periods of time (the projected lifetime of the photovoltaic plant)an assumption of linear annual degradation rate might be the first approximation for capital investment costs payback time.In this study,the average annual degradation rate was calculated simply by dividing the total degradation rate by the number years of the outdoor exposure.The obtained results are presented in the form of histogram bin plot in Figure 8.More than 70%of modules have annual maximum power degradation rate lower than 0Á75%.Modules with the total circuit failure are marked with the black bin.Unfortunately,the failure time for those modules is unknown,but it is obvious that those modules exhibit manufacturing problems resulting in cells interconnections breakage.Modules preconditioning tests impact on electrical performanceAs mentioned previously many modules were sub-jected to various stress tests (based on the CEC 501Test Specification)prior to outdoor weathering.In order to identify if there is a systematic relationship between the type of testing sequence and modules performance after long-term exposure,the degradation as a function of test sequence was analysed.The following preconditioning tests were carried out on the modules:-hot spot heating (HSP);short circuit conditions under 1000W/m 2Æ10%,1h,-high temperature storage (HTS);90Æ28C,20days,-ultra violet exposure (UVE);50Æ28C,total UV fluence of 15kWh/m 2,-high temperature high humidity storage (HTH);90Æ28C,95Æ3%RH,20days,-thermal cycling (TC50);from À20to þ808C,50cycles with total duration 400h,-humidity freezing (HUF);À208C,85%RH,2cycles with total duration of 72h,-salt mist test (SALT);358C,50g/L NaCl for 4days,-ice formation (ICE);water spraying at À208C,aver-age ice layer thickness 15mm,Figure 5.The scatter plot of the dependence of the P MAXlosses on the FFlossesFigure 6.The scatter plot of the dependence of the P MAX losses on the I SClossesFigure 7.The front surface of the module from JB seriesexhibiting severe delaminationCopyright #2008John Wiley &Sons,Ltd.Prog.Photovolt:Res.Appl.2009;17:227–240DOI:10.1002/pip234 A.SKOCZEK,T.SAMPLE AND E.D.DUNLOP-damp heat(DAH);85Æ28C,95Æ3%RH,for30 days,-climatic test with O3(OZONE);258C,55Æ3% RH,O3concentration0Á5vpm for4days,-climatic test with SO2(SO2);408C,85%RH,SO2 concentration100vpm for4days.The impact of the initial accelerated stress tests on later module behavior is difficult to determine since long-term outdoor exposure is the decisive factor in the module electrical performance.Figure9shows the maximum power losses of the module series exhibiting the highest values of standard deviation.Some modules from three series:HE,FA,and IA suf-fered total circuit breakdown.Modules without prior conditioning are marked with black color.Among the presented results there is no obvious correlation between maximum power loss and initial accelerated stress test. There is only one series,HE,in which results can indicate a direct relationship between conditioning test and power loss.Modules HE03and HE04exhibit total circuit breakdown while HE01and HE02perform fairly well.However,the results can be attributed to different outdoor exposure conditions rather than the type of preconditioning test(HE01and HE02were kept at the open circuit while HE03and HE04were connected to the maximum power tracker)which will be discussed later in the paper.Concluding,the direct impact of the accelerated stress test was not confirmed but it is to be remembered that the level of the damp heat test and number of thermal cycles was less severe(as shown above)than the levels applied in today’s Type ApprovalTests.Figure9.Relative P MAX of selected modules series(black bars—no preconditioningtest)Figure8.The histogram of average calculated maximum power loss per yearCopyright#2008John Wiley&Sons,Ltd.Prog.Photovolt:Res.Appl.2009;17:227–240DOI:10.1002/pip FIELD-AGED CRYSTALLINE SILICON PHOTOVOLTAIC MODULES235。