BROOKNER E Trends in Radar and Phased Array Tech EUCAPPtrague 3-26_30-12

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Predictions and Trends for the Next Decade

Predictions and Trends for the Next Decade

Predictions and Trends for the Next DecadeThe constant evolution of technology has transformed our lives in numerous ways, and as we enter a new decade, it's fascinating to speculate on what the future holds. In this article, we will explore some predictions and trends that are likely to shape the next ten years.Artificial Intelligence (AI) is expected to continue its rapid advancement. With machine learning algorithms becoming increasingly sophisticated, AI will become more integrated into our daily lives. From voice assistants to autonomous vehicles, AI will revolutionize various industries, enhancing efficiency and convenience.The Internet of Things (IoT) will also play a significant role in the coming decade. The ability to connect everyday devices and appliances to the internet will create a seamless network of interconnected devices. Smart homes will become the norm, with automated systems controlling everything from lighting to security.5G technology will bring about a significant transformation in the way we communicate and access information. The increased speed and bandwidth offered by 5G networks will enable faster download and upload speeds, making tasks such as video streaming and online gaming even more immersive. Additionally, the Internet of Things will rely heavily on 5G connectivity, enabling real-time communication between devices.The healthcare industry is poised for a technological revolution. With advancements in medical research and technology, we can expect breakthroughs in personalized medicine, gene editing, and regenerative medicine. Wearable devices will become more prevalent, allowing individuals to monitor their health in real-time and enabling early detection of potential health issues.Renewable energy sources will gain even greater prominence in the next decade due to increased awareness of climate change and the need for sustainable alternatives. Solar and wind power will become more accessible and efficient, leading to a reduction in greenhouse gas emissions and a shift towards a greener future.Cryptocurrencies and blockchain technology will continue to disrupt traditional financial systems. As more businesses and individuals embrace cryptocurrencies, we can expect an increase in digital transactions and a decrease in reliance on traditional banking systems. Blockchain technology will also find applications beyond finance, such as supply chain management and voting systems, ensuring transparency and security.Virtual reality (VR) and augmented reality (AR) will revolutionize various industries, including gaming, entertainment, and education. VR will offer immersive experiences, allowing users to explore virtual worlds and interact with digital environments. AR, on the other hand, will enhance the real world by overlaying digital information, creating endless possibilities for education and training.Space exploration will take giant leaps in the next decade, with plans for manned missions to Mars and beyond. Private space companies will play a crucial role inexpanding our understanding of the universe and making space travel more accessible. These advancements will not only fuel scientific discoveries but also open up new opportunities for commercial space ventures.In conclusion, the next decade promises to be an exciting time filled with technological advancements and transformative changes. From AI and IoT to renewable energy and space exploration, our world is on the cusp of a new era. Embracing these predictions and trends will undoubtedly shape the future and propel us into a more connected, sustainable, and innovative world.。

初中英语教师刷题练习 11

初中英语教师刷题练习 11

绝密★启封前刷题练习 11.27英语考生注意:1.考试时间120分钟, 试卷满分150分。

2.本考试设试卷和答题纸两部分。

试卷分为第I卷(第1-12页)和第II卷(第13页),全卷共13页。

所有答题必须涂(选择题)或写(非选择题)在答题纸上,做在试卷上一律不得分。

答题前,务必在答题纸上填写准考证号和姓名,并将核对后的条形码贴在指定位置上,在答题纸反而清楚地填写姓名。

第I卷(共103分)Listening ComprehensionSection ADirections: In Section A, you will hear ten short conversations between two speakers. At the end of each conversation, a question will be asked about what was said. The conversations and the questions will be spoken only once. After you hear a conversation and the question about it, read the four possible answers on your paper, and decide which one is the best answer to the question you have heard.1.A.He knows who is knocking. B.He is eager to know who it is.C.He doesn’t want to open the door. D.He is ready to open the door.2.A.By plane. B.By bus. C.By taxi. D.By train.3.A.$100. B.$200. C.$300. D.$400.4.30.A.She went to cinema. B.She went to an exhibition.C.She stayed at home. D.She stayed with her classmates.5.A.In a doctor’s office. B.In a professor’s office.C.In an operating room. D.In an emergency ward.6.A.The man paid the tuition for learning physics. B.The man got a lot of money for his hard work.C.His hard work was not rewarding at all. D.His work before the test led to a good result.7.A.A furnished house. B.A recent book. C.A further study. D.A new record.34.A.They will go swimming. B.They will climb mountains.C.They will buy some clothes. D.They will forecast the weather conditions.8.A.He has another lecture to attend.B.He has no interest in the lecture.C.He’s attended the same lecture given by Professor Wilson bef ore.D.He might miss the lecture, if the woman didn’t remind him.9.A.She fully agrees with the man. B.They are uncertain about the weather.C.She disagrees with the man. D.She thought the man was always late.10.A. She fully agrees with the man.B. They are uncertain about the weather.C. She disagrees with the man.D. She thought the man was always late.Section BDirections: In Section B, you will hear one longer conversation and two short passages, and you will be asked several questions on each of the conversation and the passages. The conversation and the passages will be read twice, but the questions will be spoken only once. When you hear a question, read the four possible answers on your paper and decide which one would be the best answer to the question you have heard.Questions 11 through 13 are based on the following dialogue.Questions 11 through 13 are based on the following passage.11.A.People are encouraged to be a craftsman.B.Learning woodworking is not as hard as you think.C.Learning woodworking will help you know more people.D.Taking a class in woodworking will be very helpful.12.A.Because I am a talent in this art and want to share it with others.B.Because I am interested in it and want to show it to others.C.Because I wonder how to pick materials and how to do it well.D.Because it’s a good way to know more people interested in it.13.A.You can expect to do woodworking perfectly the very first time. B.Doing woodworking means being alone for long.C.You can also learn from other people interested in woodworking. D.Taking a class in woodworking costs a lot of money.Questions 14 through 16 are based on the following passage.14.A.To analyze causes and effects of using a credit card.B.To encourage people to borrow money from banks.C.To let people know the responsibility in using a credit card.D.To present the effect of computers in popularizing the use of credit cards. 15.A.The development of computers.B.People’s greediness for more money.C.People’s needs for less paper money.D.People’s learning to be more responsible.16.A.To learn to be responsible by using credit cards.B.To stop using credit cards and borrow money from friends or relatives. C.To pay money back as fast as possible after using credit cards.D.To stop borrowing money and use your own funds for shopping. Questions 17 through 20 are based on the following passage.17.A.A newspaper. B.An advertisement company.C.A cleanup company. D.A market.18.A.She wants to spare more room for something new.B.She wants to turn their old stuff into cash at a low cost.C.She knows that the sales consultant before the man does.D.She just wants to clean up their house.19.A.Rudy is likely to buy their stuff.B.Rudy will come and take their stuff away.C.Rudy plays guitar as well as the man.D.Rudy will help them with the ad and the sale.20.A.His old guitar.B.Their appliances, jewelry, furniture and exercise equipment.C.The spring cleanup sale.D.The low cost of ad and friendly service.II. Grammar and VocabularySection ADirections: After reading the passages below, fill in the blanks to make the passages coherent and grammatically correct. For the blanks with a given word, fill in each blank with the proper form. of the given word; for the other blanks, use one word that best fits each blank.A painter hangs his or her finished pictures on a wall, and everyone can see it. A composer writes a work, but no one can hear it 21.it is performed. Professional singers and players have great responsibilities, for the composer is absolutely dependent on them. A student of music needs as long and as tough a training to become a performer as a medical student needs22.(become)a doctor. Most training is concerned23.technique, for musicians have to be as muscularly skillful as an athlete or a ballet dancer. Singers practice breathing every day, as their vocal chords(声带)would be inadequate without24.(control)muscular support. String players practice moving the fingers of the left hand up and down, while drawing the bow back and forth with the right arm,25.are two entirely different movements.Singers and instruments have to be able to get every note perfectly in tune. Pianists 26.(spare)this particular anxiety, for the notes are already there, and it is the piano tuner’s responsibility to tune the instrument for27.. But they have their own difficulties; the hammers that hit the string must be dealt with carefully not to sound like drum or bass, and each tone, even if played very fast, has to sound clear.The problem28.(face)student conductors is that they have to learn to know every note of the music and29.it should sound, and they need to aim at controlling these sound with enthusiastic but selfless authority.Technique is of no use unless it is combined with musical knowledge and understanding. Great artists are those who are so thoroughly at home in the language of music30.they canenjoy performing works written in any century.Section BDirections: Fill in each blank with a proper word chosen from the box. Each word can beDear Admissions Committee,I had the pleasure of teaching Sara in her 11th grade honors English class at Mark Twain High School. From the first day of class, Sara impressed me with her ability to clearly explain difficult 31.and texts, her sensitivity to the slight differences within literature, and her passion for reading, writing, and creative expression— both in and out of the classroom. Sara is a talented literary critic and poet, and she has my highest 32.as a student and writer.Sara is talented at considering the elegances within literature and the 33.behind authors' works. She produced an extraordinary year-long thesis paper on creative identity development, in which she compared works from three different time periods and synthesized cultural and historical 34.to inform her analysis. When called upon to give her thesis defense in front of her peers, Sara spoke clearly and35.about her conclusions and responded to questions in a thoughtful way. Outside of the classroom, Sara is devoted to her literary pursuits, especially to poetry. She publishes her poetry in our school's literary magazine, as well as in online magazines. She is an insightful, sensitive, and deeply self-aware individual driven to 36.art, writing, and a deeper understanding of the human condition.Throughout the year Sara was an active participant in our discussions, and she always supported her peers. Her caring nature and personality allow her to work well with others in a team setting, as she always respects others' opinions even when they differ from her own. When we held a class debate about gun laws, Sara chose to speak for the side opposite her own views. She explained her choice as37.by a desire to put herself in other people's shoes, view the issues from a new perspective, and gain a clearer sense of the issue from all angles. Throughout the year, Sara 38.this openness to the opinions, feelings, and perspectives of others, along with sharp powers of observation, all 39.that make her outstanding as a student of literature and burgeoning writer.I am certain that Sara is going to continue to do great and creative things in her future. I highly recommend her for admission to your undergraduate program. She is talented, caring, dedicated, and focused in her pursuits. Sara consistently seeks out 40.feedback so she can improve her writing skills, which is a rare and impressive quality in a high school student. Sara is truly a stand-out individual who will impress everyone she meets. Please feel free to contact me if ********************************************.Sincerely,Ms. ScribeEnglish TeacherMark Twain High SchoolIII. Reading ComprehensionSection ADirections: For each blank in the following passage there are four words or phrases marked A, B, C and D. Fill in each blank with the word or phrase that best fits the context.Research has shown that two-thirds of human conversation is taken up not with discussion of the cultural or political problems of the day, not heated debates about films we've just watched or books we've just finished reading, but plain and simple 41 .Language is our greatest treasure as a species, and what do we 42 do with it? We gossip. About others' behaviour and private lives, such as who's doing what with whom, who's in and who's out——and why; how to deal with difficult 43 situations involving children, lovers, and colleagues.So why are we keen on gossiping? Are we just natural 44 , of both time and words? Or do we talk a lot about nothing in particular simply to avoid facing up to the really important issues of life? It's not the case according to Professor Robin Dunbar. In fact, in his latest book, Grooming, Gossip and the Evolution of Language, the psychologist says gossip is one of these really 45 issues.Dunbar 46 the traditional view that language was developed by the men at the early stage of social development in order to organize their manly hunting activities more effectively, or even to promote the exchange of poetic stories about their origins and the supernatural. Instead he suggests that language evolved among women. We don't spend two-thirds of our time gossiping just because we can talk, argues Dunbar —47 , he goes on to say, language evolved specifically to allow us to gossip.Dunbar arrived at his cheery theory by studying the 48 of the higher primates like monkeys. By means of grooming——cleaning the fur by brushing it, monkeys form groups with other individuals on whom they can rely for support in the event of some kind of conflict within the group or 49 from outside it.As we human beings evolve from a particular branch of the primate family, Dunbar 50 that at one time in our history we did much the same. Grouping together made sense because the bigger the group, the greater the 51 it provided; on the other hand, the bigger the group, the greater the stresses of living close to others. Grooming helped to 52 the pressure and calm everybody down.But as the groups got bigger and bigger, the amount of time spent in grooming activities also had to be 53 to maintain its effectiveness. Clearly, a more 54 kind of grooming was needed, and thus language evolved as a kind of vocal grooming which allowed humans to develop relationship with ever-larger groups by exchanging information over a wider network of individuals than would be possible by one-to-one 55 contact.41.A.claim B.description C.gossip D.language42.A.occasionally B.habitually C.independently D.originally 43.A.social B.political C.historical D.cultural44.A.admirers B.masters C.users D.wasters45.A.vital B.sensitive C.ideal D.difficult46.A.confirms B.rejects C.outlines D.broadens47.A.for instance B.in addition C.on the contrary D.as a result 48.A.motivation B.appearance C.emotion D.behavior49.A.attack B.contact C.inspection D.assistance50.A.recalls B.denies C.concludes D.confesses51.A.prospect B.responsibility C.leadership D.protection 52.A.measure B.show C.maintain D.ease53.A.saved B.extended C.consumed D.gained54.A.common B.efficient C.scientific D.thoughtful55.A.indirect B.daily C.physical D.secretSection BDirection:Read the following three passages. Each passage is followed by several questions or unfinished sattments. For each of them there are four choices markedA, B, C and D. Choose the one that fits best according to the information given in the passage you have just read.(A)In a career that lasted more than half a century, Tom Wolfe wrote fiction and nonfictionbest-sellers including The Electric Kool-Aid Acid Test and The Bonfire of the Vanities. Along the way, he created a new type of journalism and coined phrases that became part of the American vocabulary.Wolfe began working as a newspaper reporter, first for The Washington Post, then the New York Herald Tribune. He developed a literary style in nonfiction that became known as the “New Journalism.” “I’ve always agreed on a theoretical level that the techniques for fiction and nonfiction are interchangeable,” he said. “The things that work in nonfiction would work in fiction, and vice versa.”“When Tom Wolfe’s voice broke into the world of nonfiction, it was a time when a lot of writers, and a lot of artists in general, were turning inwards,” says Lev Grossman, book critic for Time magazine. “Wolfe didn’t do that. Wolfe turned outwards. He was a guy who was interested in other people.” Wolfe was interested in how they thought, how they did things and how the things they did affected the world around them.In 1979, Wolfe published The Right Stuff, an account of the military test pilots who became America’s first astronauts. Four years later, the book was adapted as a feature film. “The Right Stuff was the book for me,” says Grossman. “It reminded me, in case I’d forgotten, that the world is an incredible pla ce.”In The Right Stuff, Wolfe popularized the phrase “pushing the envelope.” In a New York magazine article, Wolfe described the 1970s as “The ‘Me’ Decade.” Grossman says these phrases became part of the American idiom because they were accurate.“He was an enormously forceful observer, and he was not afraid of making strong claims about what was happening in reality,” Grossman says. “He did it well and people heard him. And they repeated what he said because he was right.” All those words started a revolu tion in nonfiction that is still going on.56. The “New Journalism” is a style of journalism that .A. changes its news writing techniques frequentlyB. popularizes new American idioms in a literary wayC. combines novelistic techniques with traditional reportingD. reports various news events from a theoretical perspective57. It can be learned from the passage that The Right Stuff .A. is a film directed by Lev GrossmanB. is an influential book by Tom WolfeC. accounts for popular American phrasesD. deals with incredible places in the world58. According to the passage, Tom Wolfe .A. was good at reporting news from a realistic perspectiveB. preferred making claims about events to writing booksC. was fond of commenting on other people’s though tsD. liked analyzing social problems from the outside59. Which of the following is the best title for the passage?A. Tom Wolfe: A Professional Phrase CoinerB. Tom Wolfe: A Forceful Observer and NovelistC. Tom Wolfe: A Theoretical Creator in LiteratureD. Tom Wolfe: An Innovative Journalist and Writer(B)The idea of using radio or wireless to broadcast to audiences was formed in 1916 by a president of the American Marconi Company, David Sarnoff. His superiors were doubtful about his idea to “make radio a household cause, so that by purchase of a ‘radio music box’, the audience could enjoy lectures, music performance, etc.”Four years later the American engineer Frank Conrad, an employee at W E Corp, attracted considerable attention when a local newspaper reported on the growing audience listening on crystal radio sets to his evening and weekend amateur broadcasts. A local music store had provided records to play on the Victoria, and Conrad and his family served as disc jockeys(唱片音乐播音员). Westinghouse vice president Harry Davis asked Conrad to build a more powerful transmitter(发射台)in time to announce the outcome of the next US presidential election. Conrad completed his assignment, and on November 2, 1920, station KDKA in Pittsburgh, Pennsylvania, broadcast theannouncement that Warren G. Harding had been elected president. About 1000 people heard this first news broadcast.Radio communicated news much faster than did newspapers, and because crystal sets were easy to build and inexpensive, radio expanded rapidly in the following years. To stimulate the sale of radio sets, equipment manufactures provided transmitting facilities. Singers, comedians, and entire orchestras volunteered their services for publicity. The eventual financial basis of the new industry, however, was still unclear. One group in New York City tried to seek contributions from listeners while others urged that private foundations support radio stations as a public service. In August 1922 the first commercial radio advertisement was broadcast on WEAF (now WNBC) in New York City. In 1926, when about 5 million homes had radios, the Radio Corporation of America (RCA), in cooperation with the American Telephone & Telegraph Company, established the first commercial radio network. In the 1920s radio was established as a new mass medium had a practicable industry, and it became a national forum(论坛)for news and popular culture. 59.The passage is mainly concerned with _______.A.the contribution of radio to popular cultureB.the invention and uses of radioC.early radio programs for a mass audienceD.the history of radio broadcasting60.Who started broadcasting radio programs to mass audience?A.Frank Conrad B.David Sarnoff C.Harry Davis D.Warren Harding 61.After 1920, radio expanded rapidly because _______.A.people could easily get it in stores B.it was cheaper than newspapersC.it had advantages over newspapers D.people were interested in anything new62.By saying that “the eventual financial basis of the new industry was still unclear”, the author means that _______.A.the private foundations were unwilling to support the stationsB.the stations were not sure yet where to get the operational moneyC.advertising and commercial programs could not raise enough moneyD.the listeners would not pay for the broadcasting stations(C)The Earth is facing a climate crisis, but it’s also getting greener and leafier. According to new research, the rise is largely due to China and India.A study by National Aeronautics and Space Administration (NASA), based on extensive satellite photographs and published in the journal Nature Sustainability, has revealed that the two countries with the world’s biggest populations are also responsible for the largest increase in greenness.S ince 2000, the planet’s green leaf area has increased by 5 percent, or over 2 million square miles. That’s an area equivalent to the sum total of the Amazon rainforests, NASA says. But researchers stressed that the new greenery does not neutralize deforestation and its negative impacts on ecosystems elsewhere.A third of the leaf increase is thanks to China and India, due to the implementation of major tree-planting projects alongside a vast increase in agriculture.Using the data from a NASA sensor, researchers discovered that China is the source of a quarter of the increase in green leaf area, despite possessing only 6.6 percent of the world’s vegetated area (植被区). Forests account for 42 percent of that increase, while croplands make up a further 32 percen t. China’s increase in forest area is the result of forest preservation and expansion programs, NASA said, established to fight against the impacts of climate change, air pollution and soil erosion (水土流失). India has contributed a further 6.8 percent rise in green leaf area, with 82 percent from croplands and 4.4 percent from forests.Rama Nemani, a co-author of the study and a researcher at NASA’s Ames Research Center, said in a statement, “When the greening of the Earth was first observed, we thought it wa s due to a warmer, wetter climate and fertilization from the added carbon dioxide in the atmosphere, leading to more leaf growth in northern forests, for instance.” “Now, with the data that lets us understand the phenomenon at really small scales, we see t hat humans are also contributing,” Nemani said. “This will help scientists make better predictions about the behavior of different Earth systems, which will help countries make better decisions about how and when to take action.”Thomas Pugh, a professor a t the University of Birmingham’s School of Geography, Earth and Environmental Sciences, said the NASA report expands scientists’ understanding of the causes behind global greening. But he also cautioned that a direct line cannot be drawn between an increasein global greening and a decrease in negative impacts of climate change.63. The passage mainly tells us that .A. China and India have the world’s largest green leaf areasB. China and India are the lead role players in global greeningC. our planet is experiencing a climate crisis despite human effortsD. our planet is getting greener due to the joint efforts of the world64. What can be learned about China and India?A. The area of croplands in India is larger than that in China.B. India’s rise in leaf area is largely due to its forestry program.C. They both show a greater increase in forests than in croplands.D. China boasts twenty-five percent of the global rise in leaf area.65. According to Rama Nemani, their new findings are .A. unexpected but significantB. surprising but valuelessC. predictable but disappointingD. uncontrollable but inspiring66. What can be inferred from the passage?A. There is an indirect link between global greening and climate change.B. The new greenery does not have any positive effect on the global climate.C. The gain in greenness does not make up for the damage from loss of leaf area.D. The increase in greening reduces the deforestation rate and its impact globally.Section CDirections : Complete the following passage by using the sentences listed below. Each sentence can only be used once. Note that there are two sentences more than you need.Can just one person make a difference? You bet! In a community every person counts, and getting involved is not difficult. Take stock of your own talents and interests. ___67___. Don’t wait for someone else to act first. Take the initiative! Once you see what you can accomplish, you’ll want to keep going.Here are just a few ways to make a difference in your community. How many more ways can you come up with?Clean up the community. People often throw litter in places where there is already litter. And the problem only becomes worse until someone gets fed up and does something. Could your neighborhood use a cleanup? Neighborhood cleanups are often sponsored by local businesses or schools. But if your community doesn’t have a cleanup program, get together with friends to organize one. You could pick up garbage in a larger area twice a year, or you could clean a smaller area every few months. ___68___.Include the isolated. Do you know anyone who is housebound? Almost all neighborhoods have a few people who have to stay at their homes. These people are often elderly and unable to leave their homes to perform simple tasks. ___69___. By letting them “borrow” your legs and eyes, you can make them feel included. You can run errands for them like shopping or paying bills. They might like you to read to them if their eyesight is failing. Governments provide some of the services these people need, but programs cannot give them friendship; that’s what communities are for!___70___. Reading clubs are popular all over Europe and North America. Members might read at home to prepare for discussion, or they might read aloud to each other and talk about what they just read. Either way, a book or article can spark lively discussion and this often challenges people to take action.Section DDirections : Read the following passage , Summarize the main idea and the main points of thepassage in no more than 60 words . Use your own words as far as possible.Are you working with your computer routinely either as a office employee or a game lover? Are your eyes dry, watery, blurry, seeing double or sensitive to light? If your answer is a “yes”, you are likely one of many people today who suffer from digital eyestrain, also called computer-vision syndrome. What on earth is this syndrome coming from? What can we do to deal with this problem?Eyestrain is often related to the amount of exposure to screens, the distance from eyes to screens and the use of multiple screens simultaneously. However, studies have also shown that the blue light produced by digital devices today reaches further into the eyes than other kinds of light. This light actually assists attention during the day but can result in interrupted sleep patterns at night.Years of scientific researches indicate that eyestrain isn’t necessarily an unavoidable problem for those who deal with computer work in the daily base. There are ways you can adopt which can overcome the problem considerably. To begin with, your computer screen should be high-resolution(高分辨率), at least 50 centimeters wide diagonally and may require a screen filter to decrease reflections. Also, be aware that “computer glasses”, which cut down glare and blue light,are available.Besides, to reduce your risk for computer-vision syndrome, take frequent breaks during your computer workday. Many workers take only two 15-minute breaks from their computer throughout their day. According to a recent study, eyestrain are significantly reduced when computer workers take four additional five-minute “mini-breaks”throughout their workday.Finally, many of us fall into bad habits while using digital screens, which only worsen the effects of eyestrain. While viewing digital screens, many people blink (眨眼) one third less oftenthan they usually do. Place a reminder on your computer to “blink” so that your eyes don’t dry out.第II卷(共47分)I.TranslationDirections: Translate the following sentences into English, using the words given in the brackets.72. 远足是我们接触大自然的最简单方式之一。

人民大2024广告调查(第二版)英文PPTdavis_adresearch_ch1

人民大2024广告调查(第二版)英文PPTdavis_adresearch_ch1

Research Contributions: Media
▪ Research helps answer questions such as:
- How much are competitors spending? - Where, if anywhere, should the advertising be concentrated? - When and how should advertising be scheduled? - What is the optimal way to use different media? - What is the best media mix?
Slide 1 - 10
Who Conducts Research: Information Users
▪ Individuals with direct responsibility for brand- and advertising-related decisions
▪ Involved in all stages of research project: from planning to application
▪ Three dimensions of target audience analysis:
- Consumer trends - How consumers interact with brand/product/service - Relationship between consumers and brand/product/service
▪ In larger agencies there is typically a dedicated research department

机器人的英文PPT

机器人的英文PPT
The history of robot
the third stage---intelligent robotics development(1984---?)1999 Sony demonstrated the Intelligent robotics---AIBO2002 iRobot company introduced a vacuum cleaner robot Roomba.2006 Microosoft introduced Microsoft Robotics studio.
The application of robot
A robot which operates semi or fully autonomously to perform services useful to the well being of humans and equipment,excluding manufacturing operations.Care-O-Bot,helps achieve greater independence for elderly or mobility impaired persons from outside help,and therefore contributes to longer remmaining at home.Cleaning robots have entered the rger surfaces as railway ststions,airports,malls,etc.can already be cleaned automatically with full autonomous navigation capability.
Trend of Robot

核磁共振氢谱应用于高分子化学

核磁共振氢谱应用于高分子化学
材料物性研究上的重要性也与日俱增。
核磁共振原理
核磁共振研究的对象为具有磁矩的原子核。原子核是 带正电荷的粒子,其自旋运动将产生磁矩,但并非所 有同位素的原子核都有自旋运动,只有存在自旋运动 的原子核才具有磁矩。原子核的自旋运动与自旋量子 数I相关,I=0的原子核没有自旋运动,I≠0的原子核 有自旋运动。核磁共振研究的主要对象是I=1/2的原 子核,这样的原子核不具有电四极矩,核磁共振的谱 线窄,最易于核磁共振检测。原子核同时具有电荷及 自旋,根据古典电磁学理论,旋转的电荷可视为环电 流,故原子核也有对应的磁矩μ,其与自旋角动量P成 正比,关系如下:μ=γP =γI(1.1)磁矩和自旋角动量之 间的比例常数定义为旋磁比γ,旋磁比随着原子核种
核磁共振技术可对聚合物作以下几种形式 的表征:
1、共聚物中各组分的含量 2、链段长度的分析 3、聚合物相对分子量的测定 4、高聚物混合物的化学组成 5、共混及共聚物的定性定量分析 6、共聚物端基分布的测定 7、聚合物支化度的分析 8、聚烯烃立构规整度及序列结构的研究及官能团鉴别 等。
固体高分子形态研究
核磁共振氢谱应用于高分子化学
1971年J.Jeener提出了具有两个独立时间变量 的核磁共振实验,首先引入了二维谱的概念。
并由R.R.Ernst小组于1974年成功地实现了二维 核磁共振实验,之后,多维的核磁共振技术呈
现爆炸性的发展。并在超导材料的发展下,将
其导入NMR作为超强的静磁场,大幅提升了核 磁共振信号的分辨率。1973年,美国纽约州立 大学的Lauterbur在Nature杂志上发表了利用梯 度场技术可表示空间位置的质子密度,这是核
差条件,原子核即可进行能级之间的跃迁,发
生核磁共振。在考虑磁距与磁场相互作用时,

14207125袁家宝翻译译文

14207125袁家宝翻译译文

扭曲的引力模型:国际贸易的集约边际与扩展边际托马斯.切尼著袁家宝译克鲁格曼(1980)通过分析一个同质性企业模型,认为商品之间更高的替代弹性将会扩大贸易壁垒对于贸易流量的影响。

在本文中,作者将企业异质性引入一个简单的国际贸易模型。

当企业生产率符合帕累托分布的时候,接近美国企业规模观测数据的分布,克鲁格曼代表性企业模型的预测被推翻了:替代弹性没有扩大贸易壁垒对于贸易流量的影响,反而抑制了这种影响。

在克鲁格曼(1980)的研究中,尽管存在贸易壁垒,相似国家之间依然会贸易差异化产品,因为消费者偏好多样化的产品。

如果商品之间相互替代性较低,消费者愿意购买国外进口产品,即使其价格更高;另外,贸易壁垒对于双边贸易流量几乎没有影响。

从A国到B国的出口总量通过以下的表达式给定:Exports AB=Constant×GDP A×GDP B,(Trade barriers AB)σ这里σ是不同商品之间的替代弹性。

这个模型里的一个关键假设是所有企业都是同质的,并且唯一的贸易成本是可变成本。

在这两个假设之下,每一个企业向全世界每一个国家出口。

当商品之间的替代弹性较高的时候,贸易壁垒对于贸易流量有着很强的影响。

当替代弹性高的时候,企业间的竞争非常激烈,任何成本劣势都将会导致巨大的市场份额损失。

在本文中,作者将企业生产率异质性和固定出口成本引入了上述模型之中。

这些简单的修正引出了一个新的调节边际:扩展边际。

当贸易成本变化的时候,不仅是每个出口者改变其出口规模(集约边际),出口企业组合也将产生变化(扩展边际)。

本文主要的发现时替代弹性对于这两个边际有着相反的作用。

更高的替代弹性使得集约边际对于贸易壁垒的变化更加敏感,却降低了扩展边际对于贸易壁垒变化的敏感性。

原因如下。

当贸易壁垒下降的时候,生产率较低的新企业进入出口市场。

在高替代弹性的情况下,低生产率是一个严重的劣势。

这些低生产率的企业只能获得很小的市场份额。

50年代BT科洛米耶茨等人开始了对硫系玻璃的研究1968年SR

50年代BT科洛米耶茨等人开始了对硫系玻璃的研究1968年SR

第十三章非晶态半导体50年代B.T.科洛米耶茨等人开始了对硫系玻璃的研究,但直到1968年S.R.奥弗申斯基关于硫系薄膜制作开关器件的专利发表以后,才引起人们对非晶态半导体的兴趣。

1975年W.E.斯皮尔等人在硅烷辉光放电分解制备的非晶硅中实现了掺杂效应,使控制电导和制造PN 结成为可能,从而为非晶硅材料的应用开辟了广阔的前景。

在理论方面,P.W.安德森和N.F.莫脱建立了非晶态半导体的电子理论。

一、非晶态半导体的分类目前主要的非晶态半导体有两大类。

1、硫系玻璃:含硫族元素的非晶态半导体。

例如As-Se 、As-S ,通常的制备方法是熔体冷却或气相沉积。

2、四面体键非晶态半导体。

如非晶Si 、Ge 、GaAs 等,此类材料的非晶态只能用薄膜淀积的办法(如蒸发、溅射、辉光放电或化学气相淀积等),只要衬底温度足够低,淀积的薄膜就是非晶态结构。

四面体键非晶态半导体材料的性质,与制备的工艺方法和工艺条件密切相关。

图1中a 、b 是硅烷辉光放电分解,衬底温度分别为500K 和300K ,c 是溅射,d 为蒸发。

非晶硅的导电性质和光电导性质也与制备工艺密切相关。

其实,硅烷辉光放电法制备的非晶硅中,含有大量H ;不同工艺条件,氢含量不同,直接影响到材料的性质。

与此相反,硫系玻璃的性质与制备方法关系不大。

由图2可见,用熔体冷却和溅射的办法制备的As 2SeTe 2样品,它们的光吸收系数谱具有相同的曲线。

二、非晶态半导体的电子结构1、能带结构:非晶态与晶态半导体具有类似的基本能带结构,也有导带、价带和禁带。

以四面体键的非晶Ge 、Si 为例,Ge 、Si 中四个价电子经SP 3杂化,近邻原子的价电子之间形成共价键,其成键态对应于价带;反键态对应于导带。

无论是Ge 、Si 的晶态还是非晶态,基本结合方式是相同的,只是在非晶态中键角和键长也有一定程度的畸变,因而它们的基本能带结构是类似的。

2、电子态:非晶态半导体中的电子态与晶态比较有着本质的区别。

2023年高考英语新时政热点阅读 13 科学技术(含解析)

2023年高考英语新时政热点阅读 13 科学技术(含解析)

2023年高考英语新热点时文阅读-科学技术01(河北省示范性高中2022-2023学年高三9月调研考试英语试题)Housing ranks high among the numerous challenges that still need to be overcome before humans can colonize(征服) Mars. The brave pioneers that make the six-month voyage to the Red Planet will need a place to live in as soon as they land. While the best solution would be to have the structures ready before they get there, it has so far been a challenge given that most construction robots have never made it out of the laboratory. Now, there may be a bit of hope thanks to Massachusetts Institute of Technology’s newly revealed Digital Construction Platform (DCP).The DCP comprises a double arm system that is fitted on a tracked vehicle. As the larger arm moves, the smaller, precision motor robotic arm builds the structure by shooting out the necessary construction material, ranging from insulation foam(绝缘泡沫) to concrete. The team of researchers led by Ph. D.Steven Keating say that unlike other 3-D printers that are limited to building objects that fit within their overall enclosure, DCP’s free moving systems can be used to construct structures of any size.The team recently demonstrated the DCP’s building skills on an empty field in Mountain View, CA.The robot began by creating a mold with expanding foam that hardens when dry. It then constructed the building, layer by layer, using sensors to raise itself higher as it progressed. The final product was a sturdy “home” that had 50-foot diameter walls and a 12-foot high roof with room for essentials like electricity wires and water pipes to be inserted inside. Even more impressive? It took a mere 14 hours to “print”!The researchers’ next plan is to make the DCP smart enough to analyze the environment where the structure is going to be built and determine the material densities best suited for the area. However, that’s noteven the best part. Future DCP models are going to be solar-powered, autonomous, and, most importantly, capable of sourcing construction components from its surroundings. This means the robot can be sent to remote, disaster-stricken areas, and perhaps even to Mars, to build shelters using whatever material is available.1.What do we learn from the first paragraph?A.Housing pioneers on Mars is a reality.B.Colonizing Mars is out of the question.C.Building structures on Mars is in the testing phases.D.Finding a liveable place on Mars is a top priority.2.How does the DCP differ from other 3-D printers?A.It consumes less time.B.It comes in more different sizes.C.It is more environmentally friendly.D.It can build more diverse structures.3.What is the third paragraph mainly about?A.The successful case of the DCP.B.The working principle of the DCP.C.The instructions of using the DCP.D.The limitation of the DCP’s function.4.What might be the biggest highlight of future DCP ?A.Being powered by solar.B.Building shelters anywhere.C.Collecting building materials on site.D.Analyzing building material densities.02(2022·河南·洛宁县第一高级中学高三开学考试)Climate science has been rapidly advancing in recent years, but the foundations were laid hundreds of years ago.In the 1820s, French scientist Joseph Fourier theorized that Earth must have some way of keeping heat and that the atmosphere may play some role. In 1850, American scientist Eunice Newton Foote put thermometers(温度计)in glass bottles and experimented with placing them in sunlight. Inside the bottles, Foote compared dry air, wet air, N2, O2 and CO, and found that the bottle containing humid air warmed upmore and stayed hotter longer than the bottle containing dry air,and that it was followed by the bottle containing CO2. In 1859, Irish scientist John Tyndall began measuring how much heat different gases in the atmosphere absorb. And in 1896, Swedish scientist Svante Arrhenius concluded that more CO2in the atmosphere would cause the planet to heat up: These findings planted some of the earliest seeds of climate science.The first critical breakthrough happened in 1967 when Syukuro Manabe and Richard Wetherald connected energy absorbed by the atmosphere to the air movement vertically over Earth.They built a model which first included all the main physical processes related to climate changes. The predictions and the explanations based on their model still hold true in the real world almost half a century later.The model was improved in the 1980s by Klaus Hasselmann who connected short-term weather patterns with long-term climate changes. Hasselmann found that even random weather data could yield insight into broader patterns.“ The greatest uncertainty in the model remains what human beings will do. Figuring it out is 1,000 times harder than understanding the physics behind climate changes,” Manabe said.“ There are many things we can do to prevent climate change. The whole question is whether people will realize that something which will happen in20 or 30 years is something you have to respond to now.”So, it’s up to us to solve the problem that these pioneers helped the world understand.5.What does the word “humid” underlined in paragraph 2 mean?A.Cool.B.Cold.C.Dry.D.Wet.6.What is Klaus Hasselmann’s contribution to climate science?A.He found that CO2 causes global warming.B.He invented a unique measuring instrument.C.He improved Manabe and Wetherald’s model.D.He built a reliable model on climate change.7.What is paragraph 5 mainly about?A.The biggest problem with the climate model.B.The necessity for human beings to take action now.C.The challenge of understanding climate change.D.Measures to be taken to prevent climate change.8.Which of the following can be the best title for the text?A.Negative Effects of the Global WarmingB.Historic Breakthroughs in Climate ScienceC.Main Causes Leading to Climate ChangeD.Difficulties of Preventing Climate Change03(2022·河北邯郸·高三开学考试)To effectively interact with humans in crowded social settings, such as malls, hospitals, and other public spaces, robots should be able to actively participate in both group and one-to-one interactions. Most existing robots, however, have been found to perform much better when communicating with individual users than with groups of conversing humans. Hooman Hedayati and Daniel Szafir, two researchers at University of North Carolina at Chapel Hill, have recently developed a new data-driven technique that could improve how robots communicate with groups of humans.One of the reasons why many robots occasionally misbehave while participating in a group conversation is that their actions heavily rely on data collected by their sensors. Sensors, however, are prone (易于遭受) to errors, and can sometimes be disturbed by sudden movements and obstacles in the robot’s surroundings.“If the robot’s camera is masked by an obstacle for a second, the robot might not see that person, and as a result, it ignores the user,” Hedayati explained. “Based on my experience, users find these misbehaviors disturbing. The key goal of our recent project was to help robots detect and predict the position of an undetected person within the conversational group.”The technique developed by Hedayati and Szafir was trained on a series of existing datasets. By analyzing the positions of other speakers in a group, it can accurately predict the position of an undetected user.In the future, the new approach could help to enhance the conversational abilities of both existing and newly developed robots. This might in turn make them easier to serve in large public spaces, including malls, hospitals, and other public places. “The next step for us will be to improve the gaze behavior of robots in a conversational group. People find robots with a better gaze behavior more intelligent. We want to improve the gaze behavior of robots and make the human-robot conversational group more enjoyable for humans.” Hedayati said.9.What is the technique developed by Hedayati and Szafir based on?A.Data.B.Cameras.C.Existing robots.D.Social settings.10.What is mainly talked about in Paragraph 2?A.The working procedure of robots.B.The ability of robots to communicate.C.The experience of the researchers.D.The shortcomings of existing robots.11.What will happen if a robot’s camera is blocked?A.It will stop working.B.It will break down.C.It will abuse its user.D.It will misbehave.12.What do we know about the new data-driven technique?A.It is considered a failure.B.It has been used in malls.C.It gets satisfactory result.D.It only works with new robots.04(2021·浙江湖州·高三阶段练习)Researchers say they have used brain waves of a paralyzed man who cannot speak to produce words from his thoughts onto a computer. A team led by Dr. Edward Chang at the University of California, San Francisco, carried out the experiment.“Most of us take for granted how easily we communicate through speech,” Chang told The Associated Press. “It’s exciting to think we’re at the very beginning of a new chapter, a new field to ease the difficulties of patients who lost that ability.” The researchers admit that such communication methods for paralysis victims will require years of additional research. But, they say the new study marks an important step forward.Today, paralysis victims who cannot speak or write have very limited ways of communicating. For example, a victim can use a pointer attached to a hat that lets him move his head to touch words or letters on a screen. Other devices can pick up a person’s eye movements. But such methods are slow and a very limited replacement for speech.Using brain signals to work around disabilities is currently a hot field of study. Chang’s team built their experiment on earlier work. The process uses brain waves that normally control the voice system. The researchers implanted electrodes on the surface of the man’s brain, over the area that controls speech. A computer observed the patterns when he attempted to say common words such as “water” or “good.” Overtime, the computer became able to differentiate between 50 words that could form more than 1,000 sentences. Repeatedly given questions such as “How are you today?” or “Are you thirsty,” the device enabled the man to answer “I am very good” or “No, I am not thirsty.” The words were not voiced, but were turned into text on the computer.In an opinion article published with the study, Harvard brain doctors Leigh Hochberg and Sydney Cash called the work a “pioneering study.” The two doctors said the technology might one day help people with injuries, strokes or diseases like Lou Gehrig’s. People with such diseases have brains that “prepare messages for delivery, but those messages are trapped,” they wrote.13.How is the new method different from the current ones?A.It involves a patient’s brain waves.B.It can pick up a patient’s eye movements.C.It is a very limited replacement for speech.D.It can help a patient regain his speech ability.14.What does the underlined word “differentiate” in paragraph 4 mean?A.Organize.B.Learn.C.Distinguish.D.Speak.15.What was Leigh Hochberg and Sydney Cash’s attitude towards the study?A.Positive.B.Negative.C.Doubtful.D.Critical.16.Which of the following is the best title for the text?A.Researchers Found Good Methods to Help Paralyzed PatientsB.Device Uses Brain Waves of Paralyzed Man to Help Him CommunicateC.Years of Additional Work Needed to Improve the Communication MethodsD.Device Uses Brain Waves of Paralyzed Man to Cure His Speaking Disability05(2022·安徽·高三开学考试)When people think of farming today, they usually picture a tractor (拖拉机) rather than horses in the farmland. That’s because tractors that relied on engines revolutionized farming in the late 1800s. Now a new type of tractor can do the same in the 21st century.Agriculture has been changing dramatically in the last few decades. The push for innovation is fed by the need to produce larger amounts of food for a growing world population. Autonomous tractors may be the key to solving this challenge. They can be used to carry out labor-intensive farming while allowing farmersto do other work. A big plus is that it can increase crop output while reducing costs because the autonomous machines can work in all weather conditions without any rest.Part of push for automation is a shortage of farm workers due to people’s desire to have higher paying jobs with better work conditions. Farm owners are competing against companies like Amazon and restaurants that are raising wages to attract workers. “With labor shortages and the increase in the hourly wages that have to be paid in order to be competitive, all of a sudden automation seems like a more reasonable decision,” said David Swartz, a professor at Penn State University.Many believe the time is ripe for an autonomous revolution because robotics is already in use in agriculture. One company that is working to bring autonomous tractors into main stream farming is Blue and White Robotics, an Israeli agricultural technology company, whose mission is to make a fully autonomous farm. The company released an autonomous tractor kit in February 2021 that can be fixed on any existing tractor. The kit includes camera detection, speed controls, as well as an anti-crash system. Blue and White’s kit is being used by West Coast growers in the US. It may soon come to a farm near you.17.What contributes to the agricultural revolution according to Paragraph 2?A.The urge to feed more people.B.The extreme weather conditions.C.The need to reduce farming cost.D.The desire for automatic farming.18.What is Swartz’s attitude to automation?A.Critical.B.Negative.C.Supportive.D.Indifferent.19.What can be inferred about Blue and White’s kit?A.It has been widely used.B.It can be made in many firms.C.It can improve safety of tractors.D.It will detect the way of farming.20.What may be a suitable title for the text?A.Automation Is Transforming Agriculture B.Big Companies Are Making A Difference C.Driverless Tractors Are Worth Investing D.Traditional Farming Is Falling out of Date参考答案:1.C2.D3.A4.C【导语】本文是一篇说明文。

托福阅读tpo70R-2原文+译文+题目+答案+背景知识

托福阅读tpo70R-2原文+译文+题目+答案+背景知识

托福阅读tpo70R-2Nineteenth-Century Theories of Mountain Formation原文 (1)译文 (5)题目 (8)答案 (16)背景知识 (17)原文Nineteenth-Century Theories of Mountain Formation①One of the central scientific questions of nineteenth-century geology was the origin of mountains.How were they formed?What process squeezed and folded rocks like bread dough?What made Earth's surface move?Most theories invoked terrestrial contraction as a causal force.It was widely believed that Earth had formed as a hot,incandescent body and had been steadily cooling since the beginning of geological time.Because most materials contract as they cool,it seemed logical to assume that Earth had been contracting as it cooled,too.As it did,its surface would have deformed,producing mountains.②In Europe,Austrian geologist Eduard Suess(1831-1914)popularized the image of Earth as a drying apple:as the planet contracted,its surface wrinkled to accommodate the diminished surface area.Suess assumed that Earth’s initial crust was continuous but broke apart as the interior shrank.The collapsed portions formed the ocean basins, the remaining elevated portions formed the continents.With continued cooling,the original continents became unstable and collapsed to form the next generation of ocean floor,and what had formerly been ocean now became dry land.Over the course of geological history,there would be a continual interchange of land and sea,a periodic rearrangement of the landmasses.③The interchangeability of continents and oceans explained a number of other perplexing geological observations,such as the presence of marine fossils on land(which had long before puzzled Leonardo da Vinci)and the extensive interleaving of marine and terrestrial sediments in the stratigraphic record.Suess's theory also explained the striking similarities of fossils in parts of Africa and South America. Indeed,in some cases the fossils seemed to be identical,even though they were found thousands of miles apart.These similarities had beenrecognized since the mid-nineteenth century,but they had been made newly problematic by Darwin's theory of evolution.If plants and animals had evolved independently in different places within diverse environments,then why did they look so similar?Suess explained this conundrum by attributing these similar species to an early geological age when the continents were contiguous in an ancient supercontinent called Gondwanaland.④Suess’s theory was widely discussed and to varying degrees accepted in Europe,but in North America geologist James Dwight Dana(1813-1895)had developed a different version of contraction theory.Dana suggested that the continents had formed early in Earth history,when low-temperature minerals such as quartz and feldspar had solidified.Then the globe continued to cool and contract,until the high-temperature minerals such as olivine and pyroxene finally solidified—on the Moon,to form the lunar craters,on Earth,to form the ocean basins.As contraction continued after Earth was solid,its surface began to deform.The boundaries between continents and oceans were most affected by the pressure,and so mountains began to form along continental margins.With continued contraction came continued deformation,but with the continents and oceans always inthe same relative positions.Although Dana's theory was a version of contraction,it came to be known as permanence theory,because it viewed continents and oceans as globally permanent features.⑤In North America permanence theory was linked to the theory of subsidence(or sinking)of sedimentary basins along continental margins.This idea was developed primarily by paleontologist James Hall(1811-1898),who noted that beneath the forest cover,the Appalachian Mountains of North America were built up of folded layers of shallow-water sedimentary rocks,thousands of feet thick.How did these sequences of shallow-water deposits form?How were they folded and uplifted into mountains?Hall suggested that materials eroded off the continents accumulated in the adjacent marginal basins, causing the basins to subside.Subsidence allowed more sediment to accumulate,causing more subsidence,until finally the weight of the pile caused the sediments to be heated,converted to rock,and then uplifted into mountains.Dana modified Hall's view by arguing that thick sedimentary piles were not the cause of subsidence but the result of it.Either way,the theory provided a concise explanation of how thick sequences of shallow-water rocks could accumulate,but was vague on the question of how they were transformed into mountainbelts.译文19世纪山脉形成理论①十九世纪地质学中的一个核心科学问题是山脉的起源。

中国渔业节能减排状况及发展建议

中国渔业节能减排状况及发展建议
( 农业农村部渔业装备与工程技术重点实验室,中国水产科学研究院渔业机械仪器研究所,上海,200092)
摘要:进入 21 世纪,中国渔业得到了更加快速的发展,也取得了一些令人瞩目的成绩,极大地弥补了优质蛋 白源短缺,为中国粮食安全提供了重要保障。 但是,渔业是一个对能源和资源有较大依赖的行业,在快速发 展的同时,也付出环境和能耗的代价,粗放的生产模式,给周围环境带来赤潮、水华等负面影响,渔船燃油生 产性成本投入已超过捕捞总成本的 2 / 3,这已经成为制约渔业可持续发展主要障碍。 党的十八大报告提出 大力推进生态文明建设,为渔业的发展指明了方向。 本文重点介绍了国内外水产养殖、水产捕捞、水产品加 工领域的节能减排发展情况。 与国外渔业发达国家相比,国内在渔业这 3 个领域的节能减排研究应用起步 较晚、基础较弱,但发展较快、成果较好,节能减排的动力和潜力也较大。 同时,对今后的发展提出了建议:一 是积极采取措施,促进生产方式向节能减排方向转变;二是加强基础性、关键性技术研究,推进传统生产方式 转型升级;三是加强新产品、新技术的示范推广,建立引领性水产高效生产新模式。 本研究以期为渔业转型 升级,走节能减排绿色可持续发展之路提供参考。 关键词:渔业;水产养殖;水产捕捞;水产品加工;节能减排;发展;建议 中图分类号:S969 文献标志码:A 文章编号:1007-9580(2021)03-0010-08
养殖模式方面,主要 是 通 过 构 建 鱼 - 微 生 物、 渔农结合等方式,实现养殖尾水的零排放。 “ 十 三五” 期间,在全国形成许多新的模式,尤其是在 全国淡水渔业主产区,采用了池塘设施化工程技 术、池塘环境生态设施与装备技术等,形成了黄河 滩涂提质增效型养殖模式等绿色高效养殖典型模 式,并以此为基础建立 14 个养殖模式示范点( 表 1) ,取得良好的经济和示范效果。

重庆市巴蜀中学2023-2024学年高二上学期期中英语试卷

重庆市巴蜀中学2023-2024学年高二上学期期中英语试卷

高2025届高二(上) 半期考试英语试卷(命题人: 徐薇、孙小涵审题人: 杨静)注意事项:1. 答题前, 考生务必将自己的姓名、准考证号、班级、学校在答题卡上填写清楚。

2. 每小题选出答案后, 用2B铅笔把答题卡上对应题目的答案标号涂黑, 如需改动, 用橡皮擦干净后, 再选涂其他答案标号。

在试卷上作答无效。

3. 考试结束后, 请将答题卡交回, 试卷自行保存。

满分150分, 考试用时120分钟。

第I卷(选择题)第一部分听力(共两节, 满分20分)第一节(共5小题: 每小题1分, 满分5分)听下面5段对话。

每段对话后有一个小题, 从题中所给的A、B、C三个选项中选出最佳选项。

听完每段对话后, 你都有10秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

1. What’s wrong with the woman’s foot?A. It’s broken.B. It has a skin disease.C. It got burned by hot oil.2. What was Sparky probably doing?A. Trying on a hat.B. Destroying a hat or a tie.C. Chewing on one of his toys.3. Where does the woman want to go?A. To the office.B. To the library.C. To the dining hall.4. Why did the woman start her business?A. To learn about dogs.B. To help her neighbors.C. To finish a research project for school.5. Where might the speakers be?A. On a bridge.B. At a movie theater.C. In a car.第二节(共15小题: 每小题1分, 满分15分)听下面5 段对话或独白。

外文翻译---相控阵和雷达技术的突破

外文翻译---相控阵和雷达技术的突破

毕业设计(论文)外文文献翻译翻译(1)题目相控阵和雷达技术的突破翻译(2)题目发射KU-波段的相控阵天线在FSS通信系统中的应用学院电子信息学院专业英文译文1:相控阵和雷达技术的突破【摘要】许多人认为雷达是一个成熟的领域,不会发生任何新的变化,这种看法存在很久了,没有比这个看法更错误的了。

当我1950年参与到雷达领域的时候,我也有过同样的看法,例如,我认为麻省理工学院的雷达丛书已经是包罗万象了,不需要增加任何新的内容。

然而我是多么的错啊,从那时起雷达技术领域中已经发生了许多令人眼花缭乱的发展,雷达一直受益于Moore s定律和许多新的技术上的成果,例如,MMIC GaAs T/R组件和相控阵组件。

现在雷达技术发展得更快了,在这篇文章里,我将给出某些最近突破的例子。

【关键词】雷达;有源相控阵;MMIC;MEMS;T/R组件;相控阵;AESA;电扫;GaAs;GaN;SiC;CMOS;数字波束形成;自适应阵列;旁瓣对消器;超宽带天线;金属材料;电子管;真空电子器件;回旋管;磁控管;速调管;行波管;微波功率组件;MPM;功率放大组件;SBX;GBR—P0:SEA-BASED X-波段雷达24层楼高的SEA-BASED X-波段相控阵雷达是一个世界奇迹。

1:GaAs MMIC T/R模块(单片微波集成电路)在过去的十年成功和广泛的应用了MMIC和AESA(有源电子扫描阵)2:低成本¥19K AESA谁说AESA是非常昂贵的,在DARPA(Defense Advanced Research Projects Agency美国国防部先进研究项目局)的低资金¥19K资助下使35GHZ相控阵成为可能。

DARPA 已经资助发展了¥10 X-band,10’smW,单T/R芯片模块。

3:低成本的MEMS(微机电系统)相控阵即使我们只有一个低损耗的移相器,那么就能够用在一个模块上安装很多的移相而MEMS提供了这个可能。

一种新的部分神经进化网络的股票预测(英文)

一种新的部分神经进化网络的股票预测(英文)

一种新的部分神经进化网络的股票预测(英文)一种新的部分神经进化网络的股票预测自从股票市场的出现以来,人们一直在寻求能够提前预测股票走势的方法。

许多投资者和研究人员尝试使用各种技术分析工具和模型来预测股票未来的走势,但是股票市场的复杂性和难以预测性使得这变得困难重重。

因此,寻找一种能够准确预测股票走势的方法一直是金融界的热点问题。

近年来,人工智能技术在金融领域的应用日益增多。

其中,神经网络是一种被广泛使用的工具,它可以自动学习和识别模式,并根据所学的模式进行预测。

然而,传统神经网络在预测股票市场方面存在诸多问题,例如过拟合和难以处理大量数据等。

为了克服这些问题,本文提出了一种新的部分神经进化网络(Partial Neural Evolving Network, PNEN)模型来预测股票走势。

PNEN模型将神经网络和进化算法相结合,通过优化和训练来实现更准确的预测结果。

PNEN模型的核心思想是将神经网络的隐藏层拆分为多个小模块,每个小模块只负责处理一部分输入数据。

通过这种方式,模型可以更好地适应不同的市场情况和模式。

同时,采用进化算法来优化模型的参数,可以进一步提高模型的预测性能。

具体而言,PNEN模型包括以下几个步骤:1. 数据准备:从股票市场获取历史交易数据,并对数据进行预处理和归一化处理,以便更好地输入到模型中。

2. 构建模型结构:将神经网络的隐藏层拆分为多个小模块,通过进化算法来确定每个小模块的结构和参数。

进化算法通过优化模型的准确性和稳定性,以获得更好的预测结果。

3. 训练模型:使用历史数据集对模型进行训练,并通过反向传播算法来更新模型的权重和偏置。

同时,通过与进化算法的交互,不断调整模型结构和参数。

4. 预测结果:使用训练好的模型对未来的股票走势进行预测。

通过模型对市场的分析和判断,可以为投资者提供决策参考。

为了验证PNEN模型的效果,我们在实际的股票市场数据上进行了实验。

结果表明,与传统神经网络模型相比,PNEN 模型在预测股票走势方面具有更好的准确性和稳定性。

22825458

22825458

员并不知道这些化合物在动物体 内究竟起 了什 么作用 , 他们完 {领 导 研 制 出 世 界 上 第 一 种 降 胆 固 醇 药 、控 制 前 列 腺 增 生 药 和 重 全没有在分 子水平上认识药物 的作 用 , 也从来没有做过这 方面 组乙肝疫苗等新药。当别的实验 室看到默克做 出成果 日 就开 寸
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改 变他人生 角色 的电话打到 了他 的办公 室 , 国制 药工业巨头 :方 法 。所 有 的 酶 都 有 活 性位 点 这 些 活 性 位 点 好 比是 锁 眼 中的 美 默 克公 司邀 请他担任 公司研 究部 的负责人。瓦格洛斯 拒绝了邀 锁舌 ,当配套 的 “ 钥匙 “——某种化 合物—— 精确 地顶开 “ 锁 请 我没有兴趣做 应用研究 。 默 克公司还是 盛情 邀他 到总部 舌 “ 就 会 阻 止 化 学 反 应 的 发 生 。因此 , 离 出 某 种 关 键 酶 , 分 并 去访问。默 克公司的总部 在新泽西州的罗韦 这是瓦格洛斯少 j精确地确定 它的结构 研究人 员发现某种能 阻断化 学反应 的化
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光材料学英文文献(1)

光材料学英文文献(1)

Mid-Infrared Fiber LasersMarkus Pollnau1and Stuart D.Jackson21Advanced Photonics Laboratory,Institute for Biomedical Imaging,Optics and Engineering,Swiss Federal Institute of Technology1015Lausanne,Switzerlandmarkus.pollnau@epfl.ch2Optical Fibre Technology Centre,Australian Photonics CRC.The University of Sydney206National Innovation Centre,Australian Technology ParkEveleigh NSW1430,Australias.jackson@.auAbstract.The current state of the art in mid-infraredfiber lasers is reviewed in this chapter.The relevantfiber-host materials such as silicates,fluorides,chalco-genides,and ceramics,thefiber,pump,and resonator geometries,and the spectro-scopic properties of rare-earth ions are sers at transitions ranging from1.9to4µm occurring in the rare-earth ions Tm3+,Ho3+,and Er3+and their population mechanisms are discussed on the basis of the fundamental spectroscopic properties of these ions.Continuous-wave,fundamental-mode power levels ranging from a few mW near4µm up to≈10W near2µm have been demonstrated in recent years.Power-scaling methods and their limitations,the possibilities to op-timize the population mechanisms and increase the efficiencies of these lasers,as well as the prospects of future mid-infraredfiber lasers in a number of rare-earth ions at transitions in the wavelength range beyond3µm and extending to5µm are described.1IntroductionSince the introduction of the double-cladfiber more than a decade ago and with the recent technological advances in thefields offiber fabrication and beam-shaped high-power diode lasers,the performance of diode-pumpedfiber lasers has steadily improved.Today,fiber lasers can compete with their cor-responding bulk crystalline systems in certain applications,especially when transverse-fundamental-mode,continuous-wave(CW)laser operation at out-put powers in the milliwatt to multiwatt range is required.The increased recent interest infiber lasers emitting at mid-infrared wavelengths between 2and3µm primarily relates to the high potential of these wavelengths for applications in laser microsurgery.Due to the high absorption of water in the spectral region at2.7–3.0µm,high-quality laser cutting or ablation has been demonstrated in biological tissues.In addition,laser wavelengths near 2µm could be suitable for tissue welding.A number of other potential laser applications in the mid-infrared spectral region,e.g.environmental trace-gas I.T.Sorokina,K.L.Vodopyanov(Eds.):Solid-State Mid-Infrared Laser Sources,Topics Appl.Phys.89,219–255(2003)c Springer-Verlag Berlin Heidelberg2003220Markus Pollnau and Stuart D.Jacksondetection,are currently becoming increasingly important.In all these appli-cations fiber lasers may find their niches.The high development costs of fabricating fibers with sufficiently low losses in the mid-infrared spectral region has impeded the necessary research efforts in the field of mid-infrared fiber lasers.The currently available fiber materials that are suitable as host materials for specific rare-earth-doped fiber lasers in the spectral region 2–5µm will be introduced in Sect.2.More than any other idea,the invention of the double-clad fiber geometry has accelerated the output-power scaling and hence the success of fiber lasers.The various aspects of the fiber,pump,and resonator geometries will be de-scribed in Sect.3.A significant number of spectroscopic investigations has led to a better understanding of the population mechanisms of rare-earth-doped laser systems.The fundamental spectroscopic properties of rare-earth ions in solid-state host materials will be reviewed in Sect.4.Equipped with this general information,the performance of the most important mid-infrared fiber laser transitions in the wavelength range 2–3µm can be understood in detail.Sect.5will be devoted to the Tm 3+fiber lasers at 1.9and 2.3µm,whereas the Ho 3+fiber lasers at 2.1and 2.9µm will be discussed in Sect.6.An impressive example of the variety of population mechanisms and operational regimes in a single system is the Er 3+2.7µm fiber laser transition that will be investigated in Sect.7.At wavelengths beyond 3µm,it becomes increasingly difficult to find suitable host materials for actively doped laser systems.This statement holds true for glass fibers in the same way as for crystalline materials.The prospects of future mid-infrared fiber lasers in this wavelength range will be discussed in Sect.8.Besides general introductions to the different topics of lasers [1,2]that include many aspects relevant also to mid-infrared fiber lasers,a comprehen-sive introduction to the field of rare-earth-doped fiber lasers can be found in [3].2Fiber MaterialsThe choice of the fiber material involves a number of considerations:the maximum phonon energy,the environmental durability,the draw ability,the rare-earth solubility,and the purity of the starting materials.The maximum phonon energy of the glass sets the overall infrared transparency range of the fiber and the multiphonon relaxation rates which influence the quantum efficiency.The multiphonon relaxation rates for the common fiber glasses as a function of the energy gap between energy levels are shown in Fig.1.The optical transparency range relates to both the size of the band gap and also the infrared absorption cut-off,hence to the vibrational frequency νof the anion–cation bonds of the glass.For an ordered structure,ν=(1/2π) k/M ,(1)Mid-Infrared Fiber Lasers221101010M u l t i p h o n o n R e l a x a t i o n R a t e (s -1)Energy Gap (cm )Fig.1.Calculated and measured multiphonon relaxation rates as a function of the energy gap between energy levels for glasses with different maximum phonon energies.(Data taken from [4,5])where M =m 1m 2/(m 1+m 2)is the reduced mass for two bodies m 1,m 2vibrating with an elastic restoring force k .While for disordered structures like glass,this is not an accurate expression,nevertheless,it does highlight the important contributions to the glass transparency.The relative cation–anion bond strength is intimated by the field strength Z /r 2,where Z is the valence state of the cation or anion and r is the ionic radius.Generally,glasses composed of large anions and cations with low field strengths display high transparency in the mid-infrared spectral region.The important physical properties of the popular glasses used for optical fibers are shown in Table 1.Table 1.Properties of popular fiber materialsFibermaterialMax.phonon energy (cm −1)Infrared transparency (µm)Propagation losses (λat minimum)(dB/km)Thermal conductivity (W/K m)Silica1100[4]<2.50.2(1.55µm) 1.38[6]ZBLAN550[7]<6.00.05(2.55µm)0.7–0.8[8]GLS 425[5]<8.00.5(3.50µm)0.43–0.5[9]2.1SilicatesThis glass is perhaps the most important material used for optical fiber pro-duction [3,10],however,the maximum phonon energy is high (≈1100cm −1)and has so far limited the emission wavelength of mid-infrared fiber lasers us-ing this material to ≈2.2µm [11].Silica is robust and involves the very effec-222Markus Pollnau and Stuart D.Jacksontive modified chemical vapor deposition(MCVD)technique forfiber fabrica-tion.Reducing the OH−content in the glass,which has two main absorption peaks in the range1.3–2.0µm[12],improves the near-to-mid-infrared utility. Rare-earth ions such as Nd3+and Er3+which have highfield strengths have low solubility in silicate glass which can lead to clustering and micro-scale phase separation.2.2FluoridesThe use offluoride glasses,especially the heavy-metalfluorides[13,14],as host materials for mid-infraredfiber lasers has found wide acceptance.The most common form of heavy-metalfluoride glass is thefluorozirconate(ZrF4) composition and the most widespreadfluoridefiber material is ZBLAN[15], a mixture of53mol.%ZrF4,20mol.%BaF2,4mol.%LaF3,3mol.%AlF3, and20mol.%NaF.Since it can be readily drawn into single-mode optical fiber[16]it is particularly important to mid-infraredfiber lasers[17].The large atomic weight of the zirconium atom combined with relatively weak bonding provides a maximum phonon energy for ZBLAN of≈550cm−1and allows for high infrared transparency up to≈6µm.Multiphonon relaxation, however,becomes significant for transitions at wavelengths longer than≈3µpared to silica,ZBLAN has a lower damage threshold and a lower level of inhomogeneous spectral-line broadening(Sect.4.1)because the rare-earth ion is placed in sites of a less perturbed network.The crystal-field strength is also comparatively weaker[18].An overview of the spectroscopic properties of rare-earth ions doped into ZBLAN has been given in[7].2.3ChalcogenidesChalcogenides are composed of the chalcogen elements S,Se and Te[19,20,21]. They are environmentally durable,have a low toxicity and have reasonably large glass forming regions.When the rare-earth ions are doped into these glasses[22],the radiative transition probabilities and,therefore,the absorp-tion and emission cross-sections are high as a result of the high refractive in-dex(≈2.6)of the glass and the high degree of covalency of the rare-earth ion with the surrounding medium.Maximum phonon energies of300–450cm−1 produce low rates of multiphonon relaxation,see Fig.1,and therefore high quantum efficiencies.The low thermal conductivity,see Table1,is however an important factor to be considered in the design of chalcogenide-based lasers. Of the large number of rare-earth chalcogenides studied for luminescent emis-sion,the most important glasses are the sulfide glasses GaLaS(GLS)[23]and GeGaS[24]because of the reasonably high rare-earth solubility.2.4CeramicsStudies into the use of ceramics as host materials for the rare earths have recently made a lot of progress[25].These ceramics are composed of nano-Mid-Infrared Fiber Lasers223 crystallites of materials such as Y3Al5O12(YAG)and can be produced ina simple and cost-efficient process at relatively low temperatures.This allows the fabrication of materials with very high melting points[26]that are difficultto grow by other techniques such as the Czochralski method[27].This class ofmaterials is also available infiber geometry[28].Ceramicfibers combine the characteristics of crystalline materials such as high absorption and emissioncross-sections,large thermal conductivity,and even the possibility of doping with transition-metal ions[28]with the convenience of guiding the pump andsignal light in afiber.Currently,the losses of thesefibers are comparativelyhigh,but further improvement can be expected.3Fiber,Pump,and Resonator GeometriesThe light oscillating in afiber-laser resonator can be either free running or deliberately modulated depending on whether CW or pulsed output,re-spectively,is desired.Consequently,a large number of techniques for pulsedoperation including Q-switching and mode locking offiber lasers have been explored.These techniques have been investigated intensively for the commonlaser transitions at1µm in Nd3+and Yb3+and at1.5µm in Er3+,and are usually described in combination with these lasers.The smallfiber size limitsthe peak power through the damage-threshold intensity(propagating powerper core area)and,hence,crystalline lasers in bulk geometries or optical parametric processes are often preferred when high-energy short pulses areneeded.This argument accounts especially for mid-infrared ZBLAN-basedfiber lasers,because thesefibers possess a lower damage threshold compared to silicafibers.The description of mid-infraredfiber lasers is,therefore,con-fined to CW operation and specific techniques for pulsed operation offiber lasers are not discussed in this chapter.In an analogous way to the optical excitation of bulk gain media,dopedopticalfibers can be either end pumped(core pumped)or side pumped (cladding pumped).The former method is less scalable since it relies onthe use of expensive high-beam-quality pump sources because core areas areusually<100µm2.On the other hand,the larger cladding area(>104µm2) allows for high-power diode-array pumping[29,30,31,32,33].The obvious sim-plicity of the core-pumping method negates further explanation and we will concentrate on the cladding-pumping technique:one of the most important developments infiber-laser technology.3.1Fiber Designs for Cladding PumpingIn the design offibers for cladding pumping,the core of thefiber is gener-ally made to guide a single-transverse LP01mode.The shape of the mul-timode pump cladding,see Fig.2,however,remains somewhatflexible and can be shaped with a number of considerations in mind.The pump cladding,224Markus Pollnau and Stuart D.Jackson (a)(b)(d)CorePump cladding Outer cladding Jacket Fig.2.Principal double-clad fiber geometries which include (a )circular shaped pump cladding with axially positioned core,(b )circular shaped pump cladding with off-axially positioned core,(c )rectangular shaped pump cladding and (d )D-shaped pump claddingwhich in turn is surrounded by a low-refractive-index transparent polymer or glass,provides a high numerical aperture (NA)of 0.3–0.55for the pump cladding.There are three main double-clad-fiber layouts:circular,circular with offset core,and rectangular as shown schematically in Fig.2.Maxi-mum pump-light absorption sees the core near the outer edge of the circular pump cladding [34]because a portion of the launched light is skew to the fiber axis and produces an inner caustic and never crosses the central re-gion of the pump cladding.Scrambling these skew rays by bending [35]or by using a graded and slightly elliptical pump cladding [36]increases the pump-absorption efficiency as does spatially varying refractive-index fluctuations in inhomogeneous pump claddings [37].Inner caustics can be avoided by rectilinearly shaping the pump cladding [38]which has the ancillary advantage of matching the shape of diode-array output.The overall absorption coefficient of the fiber is reduced by the ratio of the core area to the area of the pump cladding [34].The propagation losses for the rectangular-shaped pump cladding are higher and the effective numerical aperture lower as compared to the circular shape [39];however,in certain cases higher dopant concentrations can provide shorter fiber lengths that also lead to reduced nonlinear effects.A D-shaped or trun-cated circular pump cladding [40],see Fig.2d,is also effective while be-ing easier to make than rectangular preforms.The circular-multimode pump cladding may also have the gain medium distributed in a ring around the edge of the pump cladding either discretely or continuously in multi-core [41]and M-profile [42]arrangements,respectively.The effective absorption coef-ficient is now further increased while maintaining high-beam-quality output.A large-mode-area core [43]can also increase the effective absorption coeffi-cient of the fiber.Recently,double-clad pump schemes have been demonstrated also with holey fibers [44].These structures offer the additional advantage of single-mode guiding over a broad spectral range [45].Mid-Infrared Fiber Lasers 2253.2Fiber-Laser ResonatorsTypical free-running fiber-laser resonators are shown schematically in Fig.3.In the simplest resonator,see Fig.3a,the pump light passes through a dichroic mirror that is highly reflective for the oscillating laser light.Fresnel reflection at the cleaved output end facet of the fiber can provide sufficient feedback for laser oscillation;however,with an output-coupler mirror –and pump retro-reflector –placed at the output end of the fiber the optical efficiency can be maximized.In an alternative arrangement,the pump light can be launched into the output end of the fiber,see Fig.3b.A dichroic mirror oriented at 45◦to the fiber axis extracts the laser output and a broadband highly reflecting mirror is placed at the rear fiber end.To scale the output power,each end of the fiber can be pumped,see Fig.3c.Periodic V-grooves [46]or prism coupling [47]along the fiber to distribute the pump access allow one to further scale the output power and are useful for pumping fiber ring resonators.Spectrally combining the output from a number of separate fiber lasers is also a promising power-scaling technique [48,49,50].The highest reported fiber-laser output powers of 110W in a singly Yb 3+-doped fiber [51]and 150W in a Nd 3+,Yb 3+-codoped fiber [52]have been obtained using arrangements as shown schematically in Fig.3c.Bragg gratings can substitute the fiber-butted mirror if spectrally well-defined output is required.PumpPump Pump Pump Output Output OutputMM M MMFiberFiberFiber(a)(b)(c)Fig.3.Schematic diagram of resonators used for free-running fiber lasers with (a )a single-end co-propagating pump,(b )a single-end counter-propagating pump and (c )dual end pumps.M represents the mirror226Markus Pollnau and Stuart D.Jackson3.3Thermal IssuesAs higher pump powers become available from laser-diode systems,it is gen-erally recognized that thermal and thermo-optical issues set limitations to the power scalability of end-pumped bulk-laser systems.Owing to the unfavor-able temperature dependence of thermal and thermo-optical parameters[53], the large heat load in the crystal leads,firstly,to a significant temperature increase in the rod,secondly,to strong thermal lensing with pronounced spherical aberrations,and ultimately,to rod fracture in a high-average-power end-pumped system.Due to its geometry,thefiber provides potentially high pump-and signal-beam intensities without the drawbacks of significant thermal and thermo-optical effects.Its large surface-area-to-volume ratio means that the heat generated from multiphonon relaxation in the core is dissipated effectively by radiation and convection from the outer surface of thefiber.This is es-pecially true for single-clad,core-pumped single-modefibers where this ratio is highest[54].Double-cladfibers have a relatively smaller surface-area-to-volume ratio and thermal issues need to be taken into account[6,55,56]. Thermal management will be required when very high output powers are desired.In particular,for high-power mid-infrared operation,thermal man-agement may be very important because of the decreased quantum efficiency and the consequently higher amount of heat dissipation.4Spectroscopic and Laser Propertiesof Rare-Earth IonsThe structure of a glass is less well defined as compared to a crystalline mate-rial.The local variation of the chemical environment of active ions in a glass has a number of consequences.Most important,the active ions may undergo chemical reactions during the fabrication process and be incorporated in the host in several oxidation states with different spectroscopic properties.Oxi-dation states other than the desired one may act as impurities that introduce undesired optical effects such as parasitic pump absorption,the reabsorption of oscillating laser light,the lifetime quenching of the laser ion,and the trap-ping of the excitation energy.A stable oxidation state of the optically active ion is thus highly desirable.The necessity of a stable oxidation state excludes a number of transition-metal ions from the list of suitable dopants in glass environments.This is one of the possible reasons why examples of transition-metal-ion-doped lasers in glass hosts are rare.On the other hand,most of the rare-earth ions prefer to stabilize in the trivalent oxidation state and are, therefore,suitable candidates as glass andfiber dopants.This chapter will, therefore,concentrate on the rare-earth ions as active dopants offiber lasers.Mid-Infrared Fiber Lasers227 4.1Spectra of Rare-Earth Ions in GlassesThe optical transitions of lanthanide(rare-earth)ions in the visible and in-frared spectral region occur within the4f subshell.This subshell is shielded by the outer5s and5p subshells and the influence of the host material isrelatively small compared to,e.g.,the3d transitions in transition-metal ions.The electronic structure of trivalent rare-earth ions derives from the perturba-tion of the4f energy level in the central-field approximation by the noncen-trosymmetric electron–electron interaction,the spin–orbit interaction,andthe crystal-field splitting(Stark effect);see the example of the energy-level scheme of Er3+in Fig.4.The spin–orbit multiplets are commonly denotedby their2S+1L J terms in Russell–Saunders coupling,although the4f elec-trons of lanthanide ions exhibit intermediate coupling and the total angularmomenta J of the spin–orbit multiplets are linear combinations of the totalorbital angular momenta L and total spins S.Single crystal-field(Stark)tran-sitions between two spin–orbit multiplets cannot be distinguished in glasses at ambient temperature,because inhomogeneous spectral-line broadening oc-curs due to the local variation of the ligand electricfield.Also homogeneous (lifetime)broadening mechanisms are relevant in a number of glasses.This spectral-line broadening makes glasses the preferred hosts when broadband,Fig.4.Energy-level scheme of triva-lent erbium indicating the splitting ofthe4f11configuration in the central-field approximation by the noncen-trosymmetric electron–electron inter-action,the spin–orbit interaction,andthe Stark splitting by the local elec-tricfield of the host material(indi-cated only for selected spin–orbit mul-tiplets)228Markus Pollnau and Stuart D.Jacksoncontinuous tunability of lasers is desired.On the other hand,the spectral-line broadening leads to lower absorption and emission cross-sections for the same transition in glasses compared to single-crystalline hosts.The reducedcross-sections lead to generally higher pump threshold of laser transitions inglasses,a fact that is compensated infiber geometry because a high pump confinement is achieved over the wholefiber length.4.2Intraionic ProcessesGenerally,the probability of an allowed electric-dipole transition is seven or-ders of magnitude larger than that of an allowed magnetic-dipole transition.Since electric-dipole transitions within the4f subshell are parity forbidden,the intensities of radiative transitions in rare-earth ions are weak and the radiative lifetimes of the emitting states are long,typically in the ms range.Mixing of the4f states with higher-lying(typically5d)electronic states of opposite parity at ion sites without inversion symmetry,however,means thatelectric-dipole transitions become partially allowed and are usually the dom-inant transitions between4f electronic states.The oscillator strengths f and integrated absorption and emission cross-sectionsσof these spin–orbit mul-tiplet-to-multiplet transitions can be calculated with the help of the semi-empirical Judd–Ofelt theory[57,58].If the degree of inhomogeneous spectral-line broadening is relatively small and the absorption and emission spectraremain structured,as is the case for ZBLAN,the cross-sectionsσ(λ)at in-dividual wavelengths that are relevant to pump absorption and stimulatedemission of narrow laser lines must be determined experimentally.Besides ground-state absorption(GSA),excited-state absorption(ESA) of pump photons,see Fig.5a,can play a significant role infiber lasers,specif-ically in the case of high-intensity core pumping.An experimental examplewill be given later in Sect.7.1.Since the absorption increases exponentially with the absorption coefficientα(λP)=Nσ(λP),ESA becomes relevant forthe population dynamics of a laser when(a)the ESA and GSA cross-sectionsσ(λP)are comparable at the pump wavelengthλP and(b)the population density N of the excited state in which the second pump-absorption steporiginates becomes a significant fraction of the density of ions in the ground state,i.e.,a large degree of ground-state bleaching must be present for ESA to play a significant role.A radiative transition from an excited state i to a lower-lying state j is characterized by the radiative rate constant A ij.If the decay occurs to sev-eral lower-lying states,the overall radiative rate constant A i is the sum of all individual rate constants.The branching ratio of each radiative transition is defined asβij=A ij/A i.Radiative decay of excited states is in competition with nonradiative decay by interaction with vibrations of the host material, called multiphonon relaxation.The rate constant of a multiphonon relaxation process decreases exponentially with the energy gap to the next lower-lying state and with the order of the process,i.e.,the number of phonons required(a)Ion (b)12Donor Ion Acceptor IonAcceptor Ion (c)Sensitizing Ion ALaser Ion B(d)1Laser Ion AQuenching Ion B (e)Donor Ion Acceptor Ion(f)1Donor Ion Acceptor Ion Fig.5.Intra-and interionic processes infiber lasers:(a)excited-state absorption (ESA);(b)energy migration;(c)sensitization and(d)quenching of a laser ion by an ion of a different type;(e)cross-relaxation and(f)energy-transfer upconversionto bridge the energy gap[59,60].This fact is illustrated in Fig.1for differ-ent glasses.The rate constant of multiphonon relaxation increases with host temperature.The measurable luminescence lifetimeτi of an excited state i is the inverse of the sum of the overall radiative rate constant A i and the rate constant of multiphonon relaxation,W i.The radiative quantum efficiency is defined asη=A i/(A i+W i).The influence of multiphonon relaxations is stronger in oxides as com-pared tofluorides because of the smaller atomic mass m2of the anion and the larger elastic restoring force k,see(1),due to stronger covalent bonds in oxides[3],both resulting in larger maximum phonon energies in oxides.A brief example:The luminescence lifetime of the4I11/2upper laser level of the erbium3µm laser(Sect.7)is partly quenched by multiphonon relaxation. Typically,nonradiative decay becomes dominant iffive or less phonons are required to bridge the energy gap.With an energy gap between the4I11/2and the next lower lying4I13/2levels of≈3400–3500cm−1,radiative decay pre-vails for phonon energies below≈600cm−1,roughly the maximum phonon energy of ZBLAN,see Table1.Fluorides are,therefore,preferred over oxides as host materials for most of the mid-infrared laser transitions.Like absorption,the strength of a stimulated-emission process is char-acterized by the emission cross-sectionσ(λL)of the laser transition.From a simple analysis,for one resonator round-trip of oscillating laser photons, the productτσ(λL)withτthe luminescence lifetime of the upper laser level, is identified as a“figure of merit”for a possible laser transition.The larger this product,the lower is the expected pump threshold of the laser transition. This“figure of merit”,however,does not take into account the numerous par-asitic effects that can occur in the population dynamics of a laser system,such as pump ESA,reabsorption of laser photons,and energy-transfer processes. It is often these parasitic processes that lead to surprising performance char-acteristics–as likely in the negative as in the positive sense–and make the interpretation of rare-earth-doped solid-state lasers challenging.Examples will be discussed in Sects.5–7.4.3Interionic ProcessesIn addition to intraionic excitation and decay mechanisms,radiative en-ergy transfer due to reabsorption of emitted photons by other active ions in the sample and nonradiative energy-transfer processes due to multipole–multipole or exchange interactions between neighboring active ions can occur. Radiative energy transfer leads to an increase in the luminescence lifetime. Among the nonradiative energy-transfer processes,most common is the elec-tric dipole–dipole interaction,which can occur as a direct[61]or phonon-assisted[62]energy transfer.A direct energy transfer requires spectral reso-nance between the involved emission and absorption transitions whereas an indirect transfer can also be nonresonant,i.e.,an existing energy gap between the emission and absorption transitions involved in the transfer is bridged by。

高中英语一轮复习语基默写选择性必修第四册UNIT 12 INNOVATION (学生版)

 高中英语一轮复习语基默写选择性必修第四册UNIT 12 INNOVATION (学生版)

UNIT 12INNOVATION(限时:20分钟)Ⅰ.阅读单词1.vitamin tablets 维生素片bour-saving machine 节省劳力的机器3.discover the causes of diseases under microscopes在显微镜下发现疾病的起因4.correspond with my friends by letters与我的朋友通信unch satellites into orbit发射卫星至轨道6.the smallest particle of matter in the universe宇宙中最小的物质微粒7.one of the 20th century’s premier scientists20世纪最重要的科学家之一8.the theory of relativity相对论9.an evolutionary biologist who studies insects一位研究昆虫的进化生物学家10.a blue mould in the dish 盘子里蓝色的霉菌11.the natural form of penicillin青霉素的天然形式12.be dressed in a smart navy blue suit穿一身漂亮的海军蓝制服13.improve the accuracy of their missiles提高他们导弹的准确度14.an outstanding physicist一位杰出的物理学家15.thousands of circuits成千上万的电路16.what a coincidence真是个巧合17.after an incubation period 经过孵化期之后18.his brilliant work in cosmology他在宇宙学方面的杰出工作19.lift a kettle top 移去壶盖20.the Industrial Revolution工业革命21.bamboo fibre竹纤维22.mechanical clocks 机械钟23.subsequently ad v.后来,随后Ⅱ.核心单词1.health and well-being健康和幸福2.garbage gathering device垃圾收集装置3.how to split the atom 如何分裂原子4.this outspoken young man这个直言不讳的年轻人5.the finding of a recent survey最近一项调查的发现6.perceive the world differently用不同的方式感知世界lions of people 数百万人8.remain humble about the amazing outcome of his discovery对他发现的惊人结果保持谦虚9.problems begin to emerge问题开始出现10.overcome the difficulty 克服困难11.his grand design for the economic future他对未来经济的宏伟计划12.under the influence of gravity在重力的影响下13.the steam engine 蒸汽机1.instant adj.立刻的,马上的;即食的n.片刻;瞬间unch v t.发射;发动,发起,开始从事3.orbit n.轨道v i. & v t.沿轨道运行4.constant adj.恒久不变的;持续不断的,经常发生的n.常量,恒量5.tube n.圆管,管子;电视显像管,阴极射线管6.decline v i.减少,降低v i. & v t.谢绝n.下降,衰退7.bonus n.意外收获,额外的好处;奖金;红利8.mass n.大量,大宗;堆;块adj.大量的Ⅲ.派生单词1.entertain v t.招待;使快乐;娱乐→entertaining adj.有趣的→entertainment n.娱乐活动,娱乐节目2.gift n.天赋;天才;才能;礼物→gifted adj.有天赋的,有才华的3.produce v t.生产→product n.产品;产物→productive adj.多产的;丰饶的;富有成效的→production n.生产;产量4.science n.科学→scientific adj.科学(上)的→scientist n.科学家5.donate v i. & v t.捐献(器官),献(血);捐赠,捐献→donation n.捐赠;捐赠物→donor n.捐赠者6.accurate adj.正确无误的;精确的;准确的→accuracy n.准确性;精准度;正确,准确→accurately ad v.准确地7.join v t.参加;加入→joint adj.联合的,共同的,共有的→jointly ad v.共同地;联合地8.efficiency n.效率→efficient adj.效率高的→efficiently ad v.有效率地,高效能地→inefficient adj.效率低的9.propose v t.提出(某观点、方法等)→proposal n.提议;建议;求婚10.clue n.线索;提示→clueless adj.一窍不通的,一无所知的11.evaluate v t.评价;评估→evaluation n.评价,评估12.theory n.理论;学说→theoretical adj.理论的13.boil v i. & v t.(使)沸腾,煮沸;(用开水)煮n.沸腾→boiling adj.很热的;炽热的→boiled adj.煮沸的,煮熟的14.improve v t.改善;改进→improvement n.改善,改进;改进之处15.available adj.可利用的;可获得的→availability n.可能性16.explode v i. & v t.(使)爆炸;急剧增长→explosion n.爆炸→explosive adj.易爆炸的17.sail v i.航行;起航→sailor n.水手,海员→sailing n.帆船运动;航行18.illustrate v t.说明,阐明;给(书籍、文章等)加插图→illustration n.图表;图解;实例,示例19.regulate v t.控制,管理→regulation n.规则;章程;管理20.preserve v t.保存(食物),腌制;维护,保护n.腌菜,果酱→preservation n.维护;保存21.specific adj.特有的;具体的;明确的→specifically ad v.特定地,专门地22.electric adj.用电的,带电的,电动的→electrical adj.电的;用电→electronic adj.电子的→electricity n.电;电能1.not to mention our knowledge of the world and space2.更不用说我们对世界和空间的了解了2.courses range from cooking to computing课程从烹饪到计算机应用都有3.figure out what to do with the plastic弄清楚如何处理塑料4.single out a few pioneers of the 20th century挑选几个20世纪的先驱5.turn to my teacher for help 向我的老师求助6.do the job in a joint effort共同努力做这项工作7.the bedroom light went out after a moment卧室的灯片刻后熄灭了8.be dedicated to improving the quality of human life致力于提高人类生活质量9.be expected to drop to 400 or below预计会降到400或更低10.be reduced to zero 减少到零11.in spite of the bad weather 尽管天气恶劣12.reflect on your successes and failures反思一下你的成功和失败1.If you had to choose the single most important discovery of the 20th century,you would have a real problem on your hands.(if引导虚拟条件句)如果你必须在20世纪重大发现中选出最重要的一项,你将会真正地陷入进退两难的境地。

专业英语四级(阅读)模拟试卷119(题后含答案及解析)

专业英语四级(阅读)模拟试卷119(题后含答案及解析)

专业英语四级(阅读)模拟试卷119(题后含答案及解析)题型有:1. 2.SECTION AIn this section there are several passages followed by ten multiple-choice questions. For each question, there are four suggested answers marked [A], [B], [C] and [D]. Choose the one that you think is the best answer.There must be few questions on which responsible opinion is so utterly divided as on that of how much sleep we ought to have. There are some who think we can leave the body to regulate these matters for itself. “The answer is easy,” says Dr.A. Burton. “With the right amount of sleep you should wake up fresh and alert five minutes before the alarm rings.”If he is right many people must be undersleeping, including myself. But we must remember that some people have a greater inertia than others. This is not meant rudely. They switch on slowly, and they are reluctant to switch off. They are alert at bedtime and sleepy when it is time to get up, and this may have nothing to do with how fatigued their bodies are, or how much sleep they must take to lose their fatigue. Other people feel sure that the present trend is towards too little sleep. To quote one medical opinion, “Thousands of people drift through life suffering from the effects of too little sleep; the reason is not that they can’t sleep.”Like advancing colonists, we do seem to be grasping ever more of the land of sleep for our waking needs, pushing the boundary back and reaching, apparently, for a point in our evolution where we will sleep no more. This in itself, of course, need not be a bad thing. What could be disastrous, however, is that we should press too quickly towards this goal, sacrificing sleep only to gain more time in which to jeopardize our civilization by actions and decisions made weak by fatigue. Then, to complete the picture, there are those who believe that most people are persuaded to sleep too much. Dr H. Roberts, writing in Every Man in Health, asserts:”It may safely be stated that, just as the majority eat too much, so the majority sleep too much.” One can see the point of this also. It would be a pity to retard our development by holding back those people who are gifted enough to work and play well with less than the average amount of sleep, if indeed it does them no harm. If one of the trends of evolution is that more of the life span is to be spent in gainful waking activity, then surely these people are in the van of this advance.1.The author seems to indicate that ______.A.there are many controversial issues like the right amount of sleepB.among many issues the right amount of sleep is the least controversialC.people are now moving towards solving many controversial issuesD.the right amount of sleep is a topic of much controversy among doctors正确答案:D解析:本题考查读者对文章首句的理解。

雷达的发展论文中英文对照资料外文翻译文献

雷达的发展论文中英文对照资料外文翻译文献

雷达的发展论文中英文对照资料外文翻译文献At the beginning of the 20th century。

XXX。

XXX for the development of radar。

However。

it was not until before and after World War II that XXX 1922.XXX objects。

In 1925.the United XXX and used it to measure the height of objects。

The US Navy also discovered continuous wave radar in 1922.which could be used on ships.During World War II。

XXX ns。

It was used to detect enemy planes and ships。

XXX。

After the war。

XXX such as air traffic control and XXX.In the 1950s and 1960s。

the development of XXX imaging of objects。

and were used in XXX.Today。

XXX。

radar will XXX industries.In the early 1930s。

XXX system for aircraft with a range of about 40 kilometers and a n of 457 meters in 1936.Two years later。

the United Kingdom deployed a chain of early warning radar XXX.Overall。

the XXX role in the n of XXX off the ionosphere。

新潮引领者的英文名词解释

新潮引领者的英文名词解释

新潮引领者的英文名词解释New Wave Influencer: Definition and Exploration of the TermIntroductionIn today's rapidly changing world, new trends and ideas emerge constantly, shaping various aspects of our lives. A new breed of individuals has emerged, known as "New Wave Influencers." This article aims to shed light on the meaning and significance of this term, exploring their role in shaping contemporary society.Defining New Wave InfluencerA New Wave Influencer refers to an individual who possesses a unique ability to identify emerging trends and effectively communicate and promote them across various mediums. They are seen as pioneers and trendsetters, with a profound impact on consumer behavior, fashion, lifestyle, and even digital culture. They possess a keen eye for innovation and an innate understanding of evolving social dynamics.Characteristics of New Wave Influencers1. Cultural Agility: New Wave Influencers are not limited by geographical boundaries. They have a global mindset, transcending cultural barriers to reach a diverse audience. Their appeal lies in their ability to bridge gaps and connect people from different backgrounds.2. Authenticity: These influencers prioritize authenticity above everything. They have managed to build a loyal fan base by staying true to their values, opinions, and vision. Their followers trust them as reliable sources of information and genuine opinions.3. Multidimensional Expertise: New Wave Influencers are proficient in multiple domains, often defying categorization. They can seamlessly blend elements of fashion, art, music, and technology, pushing boundaries and encouraging fresh perspectives.4. Proactive Adaptability: Given their role in driving trends, New Wave Influencers need to be proactive in adapting to their rapidly changing environments. They are quick to spot shifts in public sentiment and are willing to adapt their strategies accordingly.The Impact of New Wave InfluencersInfluencing Consumer Behavior: New Wave Influencers have a significant impact on consumer behavior. Through their endorsement or promotion of products and services, they shape purchasing decisions of their followers. Subsequently, businesses recognize the potential of collaborating with these influencers to reach their target markets effectively.Cultural Transformation: With their ability to bridge gaps between different cultures, New Wave Influencers bring about cultural transformations. They introduce new ideas, beliefs, and practices, challenging traditional norms and encouraging diversity and inclusivity.Digital Innovation: New Wave Influencers thrive in the digital realm, utilizing various platforms and technologies to disseminate their ideas. They take advantage of social media platforms, websites, podcasts, and even virtual reality to engage with their audiences. This innovative approach to communication has revolutionized the way information is shared and consumed.Empowerment and Social Change: Beyond shaping trends and influencing consumer behavior, New Wave Influencers empower individuals and advocate for social change. They use their platforms to address social issues, raise awareness, and inspire collective action. Their impact extends beyond the realms of branding and marketing, ensuring a positive influence on society as a whole.ConclusionNew Wave Influencers embody the spirit of innovation and forward-thinking. Through their multidimensional expertise and cultural agility, they are at the forefront of shaping trends and driving societal changes. Their influence extends well beyond consumer behavior, creating a cultural and digital revolution that inspires and empowersothers. As we navigate the complexities of an ever-changing world, their role as trendsetters and pioneers will remain crucial in shaping our collective future.。

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Achievement and Future Trends in Phased Arrays and RadarsBy Dr. Eli BrooknerRaytheon Company, 528 Boston Post Road, Sudbury, MA 01776Tel: 978-440-4007; e-mail: Eli_Brookner@EUCAP, March 26-30, 2012, Prague, CZECH RepublicSystems:• 3, 4, 6 face “Aegis” systems developed by China, Japan, Australia, Netherlands, USA;Low Cost Packaging:• Raytheon funding development of low cost flat panel X-band array using COTS type PCB;• MA-COM/Lincoln-Lab. developing low cost S-band flat panel array using PCB, overlapped subarrays and a T/R switch instead of a circulator;• Purdue Un. (and now Un. of Oklahoma) developing S-band low cost Digital Array Radar; GaN PA and A/D at every element;• Selex (British), Thales (French) and EADS (German) all developing low cost X-band arrays;• Ball and AFRL (Hanscom) developing L-, S-band geodesic dome antennas using wireless COTS for command and control,• Lockheed Martin developing COTS PCB L-band array intended for space based radar,Extreme MMIC:• T/R module on single chip possible at X- and Ka-band costing respectively less than $10 and $30 per T/R module; 8-element 8-16 GHz SiGe phased array receiver; 16-element 30-50 GHz SiGe transmit phased array, miniature (< 3mm2) and low power (<100 mW) CMOS phased array receiver at 24 GHz; 4-element SiGe/CMOS Tx/Rx phased array at 34-38 GHz with 5-bit amplitude and phase control; 2-antenna 4-simultaneous beam phased array chip at 15 GHz;Digital Beam Forming:• Israel and Australia “Aegis” AESAs have an A/D for every element channel, a major breakthrough;• Lincoln Lab and AFRL X-band have 600 MHz instantaneous wideband DBF at element development effort• Low cost DBF at element arrays for on-the-move Ethernet by IMST;• Lincoln Lab using 2W chip increases spurious free dynamic range of receiver plus A/D by 20 dB;• Radio Astronomy scientists looking at using arrays with DBF,Materials:• GaN advancing r apidly. Will be helped by use for PCs, notebooks, cell phones, servers and GaN LED industry where they are expected to replace incandescentbulbs $100 billion industry. With GaN can now put 5X the power of GaAs in same footprint.• SiGe for backend, GaAs for front end of T/R module;• Metamaterials: 1. Can now focus 6X beyond diffraction limit at 0.38 μm –Moore’s Law marches on; 2. French, ESPCI PARISTECH, demonstrated 40X diffraction limit, λ/80, at 375 MHz; Can extent to IR. 3. Used in cell phones to obtain antennas 5X smaller (1/10th λ) and have 700 MHz-2.7 GHz bandwidth simultaneously serving GPS, Blue Tooth, Wi Max and WiFi; 4. Provides isolation between closely spaced antennas and antenna elements; Un. Michigan demonstrated equivalence of 1m separation with only 2.5 cm separation of two antennas on a ground plane using electronic bandgap (EBG) material; n-doped graphene has negative index of refraction, first such material found in nature; potential being pursued for low cost electronically steered metamaterial passive phased array,Low Cost Systems:• Valeo Raytheon (now Valeo Radar) developed low cost, $100s only, car 25 GHz 7 beam phased array radar; over 1 million sold already, more than all the radars ever built up to a very few years ago;• Commercial ultra low cost 77 GHz Roach radar on 72mm2chip with >8 bits 1 GS/s A/D and 16 element array; See a man at 100’s of meters.• Un. Michigan developing low cost 240GHz 4.2x3.2x0.15 cm2 5 gm radar for bird inspired robots and crawler robots; Frequency scans 2o x8o beam ±25o; Can see a man at 600m,• DARPA has goal to build 28,000 element 94 GHz array costing $1/element, 50W total RF peak power,.Technology and Algorithms:• Butler matrix using CMOS• Potential for terahertz clock speeds using graphene transistors. Could be used for nonvolatile memory, flexible displays and camouflage clothing; self cooling; Can now be used as switch with 100,000 to 1 on/off ratio; IBM producing 200 mm wafers with RF devices,• Potential use of electron spin for memory; Nonvolatile has high density, fast write and read speeds, low power, unlimited write endurance;• Potential for use of 12 iron atoms for 1 bit of memory; provide hard drive with 100X density,• Revolutionary 3-D Micromachining: integrated circuitry for microwave components, like 16 element Ka-band array with Butler beamformer on 13X2 cm2 chip.• JPL’s SweepSAR provides wide swath SAR from space with 1/6 th power required by ScanSAR;• MIT makes major advance in solving the MEMS sticking problem that has stumped the designers for many years. Due to csimur quantum forces existing at close spacings of 100’s nm.• Iridium/GPS (IGPS) Positioning Navigation and Timing (PNT) system demonstrated ability to locate objects to within 1 cm in minute.• High resolution ISAR imaging of tank moving over rough terrain using motion compensation based on tracking history of prominent scatterers with Geometric Invariant Technique (GIT) method;• Principal Components of matrix formed from prominent scatterers track history used to determine target unknown motion and thus compensate for it to provide focused ISAR image;• S-method eliminates ISAR image blurring due to acceleration of scatterers.• Army Research Lab demonstrated 12 dB reduction in sidelobes of forward looking SAR back projection images for IED ultra wideband radar by use of Recursive Sidelobe Minimization (RSM) Algorithm;• Potential for low cost, high speed using MIM diodes;• Biodegradable array of transistors or LEDs for detecting cancer or low glucose; can then dispense chemotherapy or insulin.• 3D display from 2D image without the need for special eyeglasses. Can be use d for displaying 3D SAR and ISAR image on our radar screens. Being used for video games;• We may still achieve supe rconductivity at room temperature. Superconductivity recently obtained for first time with iron compounds. May reveal what leads to superconductivity;• 100 GFlops in cell phone using only 2 W instead of the present required 600 W for the same throughput. Goal of DARPA-Intel UHPC program for 100 to 1000 reduction in computer required power by 2018;Brookner Bio; 2-11-12BEE: The City College of the City of New York, ’53, MEE and DrSc: ColumbiaUniversity ’55 and ’62.Dr. Eli Brookner at Raytheon Company since 1962, where he is a PrincipalEngineering Fellow. There worked on ASDE-X airport radar, ASTOR AirSurveillance Radar, RADARSAT II, Affordable Ground Based Radar (AGBR),major Space Based Radar programs, NAVSPASUR S-Band upgrade, COBRADANE, PAVE PAWS, Missile Site Radar (MSR), COBRA JUDY Replacement,THAAD, Brazilian SIVAM, SPY-3, Patriot, BMEWS, UEWR, Surveillance RadarProgram (SRP), Pathfinder marine radar, Long Range Radar (upgrade for 68 ATC ARSRs), COBRA DANE Upgrade, AMDR, Space Fence, 3DELRR. Prior to Raytheon he worked on radar at Columbia University Electronics Research Lab. [now RRI], Nicolet and Rome AF Lab. Received IEEE 2006 Dennis J. Picard Medal for Radar Technology & Application “For Pioneering Contributions to Phased Array Radar System Designs, to Radar Signal Processing Designs, and to Continuing Educa tion Programs for Radar Engineers”; IEEE ’03 Warren White Award; Journal of the Franklin Institute Premium Award for best paper award for 1966; IEEE Wheeler Prize for Best Applications Paper for 1998. Fellow of IEEE, AIAA, MSS.Published four books: Tracking and Kalman Filtering Made Easy, John Wiley and Sons, Inc., 1998; Practical Phased Array Antenna Systems (1991), Aspects of Modern Radar (1988), and Radar Technology (1977), Artech House. Gives courses on Radar, Phased Arrays and Tracking aroundthe world (25 countries). Over 10,000 attended these courses. Banquet/keynote speaker twelve times. >230 papers, talks and correspondences, >100 invited. Six paper reprinted in Books of Reprints (one in two books). Contributed chapters to three books.。

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