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英语谜语大全
英语谜语大全1.What month do soldiers hate?2.How many feet are there in a yard?3.Why is an empty purse always the same?4.What book has the most stirring chapters?5.What kind of dog doesn't bite or bark?6.What is the smallest room in the world?7.What kind of water should people drink in order to be healthy?8.How do we know the ocean is friendly?9.Which can move faster, heat or cold?10.Why is the library the highest building?What month do soldiers hate?March (三月,行军)How many feet are there in a yard?It depends on how many people stand in the yard. (码,院子) Why is an empty purse always the same?There is no change in it. (零钱,变化)What book has the most stirring chapters?A cook book. (动人的,搅拌的)What kind of dog doesn't bite or bark?Hot dog. (热狗)What is the smallest room in the world?What kind of water should people drink in order to be healthy?Drink well water. (井水,健康的)How do we know the ocean is friendly?It waves. (起波浪,招手致意)Which can move faster, heat or cold?Heat, because you can catch cold. (追上冷,患感冒)Why is the library the highest building?It has the most stories. (故事,(楼)层)1. What table is in the field?2. What is the only thing you can break when you say its name?3. What is there in your house that ought to be looked into?4. What is that which you have never seen, heard or felt, which never existed and still has a name?5. What changes a pear into a pearl?6. What question can never be answered by 'Yes'?7. What ship has two mates but no captain?8. What is the most difficult key to turn?9. Where can you always find money?10. What is the surest way to double your money?11. Where does afternoon come before morning in the world?13. What letter makes a road broad?14. What letter sounds like a vegetable?15. Why is a pig the most unusual animal in the world?16. What match can't be put in a match-box?17. When do 2 and 2 make more than 4?18. I have cities but no houses, forests but no trees, rivers without water. What am I?19. I am something that has teeth but can't eat. What am I?20. What is a sick man a controdiction?Key:1.Vegetable 2.silence 3.mirror 4.nothing 5.the letter “l”6. Are you asleep?7.courtship8.a donkey9.In the dictionary 10. Fold it.11.In the dictionary 12.the bridge of a nose 13.letter B 14.letter P15.Because it is killed before it is cured (烧烤待处理)16.Football match, basketball match, etc.17.When they make 22.18.A map19.A comb20.When he is an impatient patient.Q: What are two things people never eat before breakfast? A: Lunch and supper.Q: Why did the man throw a bucket of water out the window? A: He wanted to see the waterfall.Q: Why did the man throw the butter out the window?A: He wanted to see the butterfly.Q: Why did the man put the clock in the safe?A: He wanted to save time.Q: What has two hands and a face, but no arms and legs? A: A clock.Q: What has a neck, but no head?A: A bottle.Q: Where is the ocean the deepest?A: On the bottom.Q: Why did the man throw his watch out of the window?A: He wanted to see time fly.Q: What State in the United States is High in the middle and round at the ends?A: Ohio.Q: "There were some twins. One was twenty, the other was twenty 2. One married the other. How can be this ?"A: "One was twenty, the other twenty too. One was a priest so he married the other"Q: How do you spell mousetrap?A: C-A-T.Q: How many legs does an ant have?A: Two, the same as an uncle.(HINT: ant = aunt)Q: How many people are buried in that cemetery?A: All of them.Q: What can't be used until it's broken?Q: What do tigers have that no other animals have?A: Baby tigers.Q: What is Black and white and read (red) all over?A: A newspaperSubmitted by: AshleyQ: Why is number six afraid ?A: Because seven eight nine (seven ate nine)Submitted by MR EngelsmanQ: How do you know when a motorcycle policeman is happy? A: He has bugs on his teeth!Submitted by Judy SnokeQ: What did zero say to eight?A: Nice belt.(The 8 looks like a 0 with a belt around its waist.)Q: What did number 1 say to 7?A: Nice hairIn the alphabet...Q: Which is the most self-centered letter of the alphabet?Q: Which letter is always trying to find reasons?"y" (Why?")Q: Which letter is not me?A: U.Q: What letter can do the work in one day that you can do in two days?A: W (Double u- Double you)Q: Why don't we need a compass at the North Pole?A: Because every direction is south.Submitted by Cüneyt ARASQ: Why is the A like a flower?A: Because the B is after it.Why is the letter "A" like noon?Because it's in the middle of the day.Q: "What letter of the alphabet has got lots of water?"A: "The C"Submitted by Susana P. VaronaQ: "What letter of the alphabet is always waiting in order?" A: "The Q. (queue)Submitted by José Mª PérezQ: What has two heads, four eyes, six legs and a tail?A: A horse and its rider.Q: What is as big as a horse but doesn't weigh anything? A: The horse's shadow.Q. Why was the hearse horse hoarse?A. Because of the coffinSubmitted by Ciaran P. McCarthyQ: Why are man with pierced ears better suited for marriage? Q: Because they have suffered and bought jewelry.Q: What begins with T, ends with T and has T in it?A: A teapot.Q: Do you know why birds fly to south in the winter?A: Because it's too far to walk there.Submitted by YangQ: Why do birds fly south in the fall?A: Because it's too far to walk!Submitted by Michèle LaroucheQ: Which letters do Tuesday, Thursday, Friday and Saturday have in common?A: None! None of them have "c", "o","m" or "n" in them. Submitted by Paulo José L. do AmaralI tried this one with Japanese university students. They understood all the words and enjoyed it.Q: What are the 3 important rings in life?A: Engagement ring, Wedding ring, and suffering.Q: Which room has no doors, no windows.A: A mushroom.Submitted by LUZQ: What gets wetter as it dries?A: A towelQ: A man rode into town on Tuesday. Two days later he rode home on Tuesday. How is this possible?A: His horse's name is Tuesday.Q: Why didn't the skeleton go to the dance?A: He didn't have anybody to take. (any BODY) Submitted by Toni Allen (from daughter)Q: A father and his son were in a car accident. The father died. The son was taken to the hospital. The doctor came in and said: I can't do surgery on him, because he's my son. Who was the doctor?A: The doctor was his mother.It's an old riddle that is more difficult in some countriesthan in others.Q: Why did the student take a ladder to school?A: Because he/she was going to high school!Q: Why did the tomato blush?A: Beacuse it saw the salad dressing!Submitted by: Dave WilliamsQ: What are the two strongest days of the week?A: They are Saturday and Sunday. All the others are weak (week) days.Submitted by both Motoko Hashimoto & Alfredo BilopolskyQ: How far can a dog run into the forest?A: Halfway, after that he is running out of the forest. Submitted by: Rabi'aQ: What do you call a bear without an "ear"?A: BBBBBBBSubmitted by: Drew BassettQ: Which is faster, heat or cold?A: Heat, because you can catch a cold.A: How many apples can you eat if your stomach is empty? B: 4 or 5A: No, that's wrong, because after eating one apple your stomach isn't empty.Submitted by: MiraliIf you are doing a discussion about space, then students will like this one.Q: Why did Mickey Mouse go to outer space?A: To find Pluto.Submitted by: Elisa-SN ArgentinaQ: What is the differnce between the capital of Russia and a calf's mother?A: One is Moscow, the other is a cow's Ma.(It needs to be spoken to understand it.)Q: What do you call a Spaniard who can't find his car?A: CarlosIt's pronounced "carless" (meaning without a car)Submitted by Laurence WhitesideQ: What's the difference between electricity and lightening?A: You don't have to pay for lightening.This riddle may be used when teaching a lesson on occupations.Q: What's the difference between a TEACHER and a CONDUCTOR ? A: A teacher TRAINS the MIND and a conductor MINDS the TRAIN. Submitted by: Tania Mello (Sao Paulo, Brazil)Q: What part of your body disappears when you stand up?A: Your lap. (good for phrasal 'stand up', and 'laptop',lap-dog, etc.)Submitted by: RichardQ: What do you call a witch at the beach?A: A sandwich.Submitted by TinourQ: Why did the trafic signal turn red?A: You would too if you had to change in the middle of the street.Submitted by: Drew HindsQ: What's the difference between a lion with toothache and a wet day?A: One's roaring with pain the other's pouring with rain Submitted by: Eileen DwyerQ: Why are baseball stadiums so cool?A: There is a fan in every seat.My Spanish-speaking students got a kick out of this one. Q: What do you call a person who speaks 3 languages?A: (Try to elicit responses..) Tri-Lingual.Q: What do you call a person who speaks two languages? A: (Many of them know this one) Bi-Lingual.Q: What do you call a person who speaks one language? A: An American!Submitted by: SarahQ: What do you call a fish without an eye?A: Fsh.(Hint: No "eye" = No "i")Submitted by: Kristi Swarbrick, Edmonton, AB, Canada Q: What has thirteen hearts but no body and no soul?A: A pack of playing cards.Q: What do you call a fish that only cares about himself? A: Selfish.Submitted by Cüneyt Aras, TurkeyQ: Why couldn't Mozart find his teacher?A: Because the teacher was Hayden.(Hayden --> Hidin' --> Hiding)Submitted by Sheila S. and Judy R.Q. What's a minimum?A. A very small mother!(mini-mom)Submitted by Thierry A.Q: Why can't a bicycle stand on its own?A: Because it's two-tired (too tired)Submitted by Shir NoyQ: What do you get if you cross a pig with a karate fighter? A: Pork chops.Q: What's got a head and a tail, but no body?A: A coin.Q: What's got a wave but no sea?A: My hair.Submitted by Nadia, age 7Q: What has three feet but no legs or arms?A: A yard.Submitted by Dobbin PelagiusQ: Where does a boxer who weighs 135 kilograms sit on a bus? A: Wherever he wants to.Submitted by François FalardeauWhat makes "oom" and gives milk?A cow walking backwards.Submitted by FernandoQ: What does a man say when he walks into a bar?A: Ouch!Submitted by Miguel M. Llop Díaz-CanoQ: Where does Dracula stay when he goes to New York City? A: The Vampire State building.Q: What do cows like to read?A: The mooooospaperQ: What is the longest word?A: Smiles, because there is a mile between the first and last s.Submitted by Guillermo Flores Grajales - Mexico City ESL teacher.Re-worded by another teacher.Q: What's the longest word in the English language?A: Smiles. (Because there's a mile between the first and the last letter.)A: What is the word that everybody always says wrong? B: "Wrong".Submitted by Qin HonghuaiQ: What five-letter word becomes shorter when you add two letters to it?A: ShortSubmitted by Kevin SchoeppA: What's the longest word in the dictionary?B; Rubber-band -- because it streches.Submitted by Christopher BerryQ. How many seconds are there in one year?A. Twelve. January second, February second, March second... Submitted by Mark A. ColeQ. What two days of the week start with the letter "T"?A. Tuesday and Thursday? NO, today and tomorrow! Submitted by Mark A. ColeQ: What did the doughnut say to the loaf of bread?A: If I had as much dough as you, I wouldn't be hanging around this hole.Submitted by M.PampushQ: Why did the pony have a sore throat?A: Because it was a little horse. (hoarse)Q: What did the undertaker die of?A: Coughin' (coffin)Q: Why can't a nose be twelve inches?A: Because then it would be a foot.Q: How do porcupines kiss each other?A: Very carefully.Q: What has four wheels and flies?A: A garbage truck.Q: What has teeth but can't bite?A: A Comb.Q: Why did the chicken cross the road?A: To get to the other side.Q. Why did the turkey cross the road?A. Because the chicken was on vacation.Submitted by Linda EdgertonQ. Why did the baby cross the road?A. Because it was stapled to the chicken.Q: Why did the germ cross the microscope?A: To get to the other slide!A: Why did the chewing-gum cross the road?B: Because it was stuck to the chickens foot.Submitted by Christopher BerryQ: Why did the chicken cross the road?A: To show the possum it could be done.Submitted by Alex McLeanQ: Why do people call their own language their mother tongue? A: Because their fathers seldom get a chance to use it.NOTE: For this to be funny, students need to understand thatin many cultures women have the image of speaking so much that their husbands seldom have a chance to say anything.Q: A big moron and a little moron are walking across a bridge when the big moron falls off. Why didn't the little moron fall off?A: He was a little more on.Submitted by Kevin SchoeppQ: Name one eight letter word that has kst in the middle, inthe beginning, and at the end.A: "Inkstand", "in" is at the beginning, "kst" is in themiddle, and "and" is at the end.Submitted by Kevin SchoeppQ: When does a dialect become a language?A: When its speakers get an army and a navy.Q: What is a Honeymoon Salad?A: Lettuce alone without any dressing.Submitted by David HenryQ: Why is it impossible to starve in the desert?A: Because of all the sandwiches (sand which is) there. Submitted by Shad SchroederQ: Why don't sharks eat clowns?A: Because they taste funny.Submitted by maggieQ: What would the pig say when its tailed was held tight by the farmer who had a sharp knife in his other hand?A: "That's the end of me!"Submitted by Jing Wen of San FranciscoQ: Do you know where people send a horse when it is sick? A: To a horsepital.Q: What did the doctor say when the invisible man called to make an appointment?A: Tell him I can't see him today.Submitted by Genivaldo Rodrigues SobrinhoQ: Which 'BUS' could cross the ocean?A: Columbus!Submitted by Kusuma from ThailandQ: What a bee says when it gets in the hive?A: Hi Honey! I'm home!Submitted by Bianca Lévesque -ESL Teacher , Montreal - CanadaQ: How do you catch a squirrel?A: Climb a tree and act like a nut !Submitted by Mark GrableA: Why did the boy balloon chase the girl balloon?Q: Because he wanted to see her bust!Q: What do you call a fish with no eyes?A: fsh (No letter "i", so no i's.)Q: What do you call a deer with no eyes?A: No idea. (No eye deer)Q: What do you call a deer with no eyes or legs?A: Still no idea.Q: Where do cows go for entertainment?A: They go to the mooovies!Q: What animal is it that has four legs a tail and flies?A: A dead horse!A: What is the difference between a mail box and an elephant?B: I don't know.A: I'm not going to give you any letters to post then! Submitted by Leda Giménez de Comba , from ArgentinaQ: What do you call 'a fly' without wings?A: You call it 'a walk.'Submitted by MakaronI saw this on a web-site of musician jokes. It's not original, but I thought I would share it. Here it is:Q: What's the difference between a musician and a savings bond?A: A savings bond eventually matures and earns money. Submitted by James Wilson, Mt. San Antonio CollegeQ: What color is a guitar string?A: Plink!(It is the sound the a guitar makes. The word sounds like the color "pink.")Submitted by Submitted by V. EllisonWhat goes "ZUB, ZUB"?A bee flying backwards.(Buz,Buz)wards.(Buz,Buz)Submitted by Jozef Karpat(After teaching about telling time)Teacher: What time is it?Students: Umm, eight fifty-nine?Teacher: Nope.Students: About nine o'clock?Teacher: No.Students: What then?Teacher: It's time to go home.Submitted by Kier BassQ: What did one light bulb say to another light bulb? A: You are the light of my life.Submitted by brenda "la chuca"Q: Why did the golfer take and extra pair of pants for his Saturday round of golf?A: In case he got a hole in one.Submitted by Leah DavisQ. Why did the golfer wear two pairs of trousers?A. In case he got a hole in one!Submitted by Lesley MorganQ: What flowers have two lips?A: TulipsQ: They travel all over the world but end up in the corner, what are they?A: StampsSubmitted by Takya, Malaysia.Q: Why didn't the farmer cry when his dairy cow fell off the cliff?A: There's no use crying over split milk.Submitted by Alfred VincentQ: Ten copycats were sitting in a boat, and one jumped out. How many were left?A: None. They were all copycats.Q: What is the difference between a jeweler and a jailor? A: A jeweler sells watches. A jailer watches cells. Submitted by Cristina TosoQ: What is a bachelor?A: A man who never Mrs. (misses) anyone.Submitted by C. BerryQ: Why do cows have bells?A: Because their horns don't work.Submitted by Barbara KoehlerThis one may be difficult for some ESL students since it requires knowing the words "seagul", "bay" and "bagel"Q: Why do seagulls fly over the sea?A: Because if they flew over the bay, they would be bagels! Submitted by Corey Palmer, Lemoore, CAQ: What's the difference between a trampoline and an English textbook?A: You take off your shoes before jumping on a trampoline. Q: How do you get ten English teachers to agree on the best teaching method?A: Shoot nine of them.(Use as an example of the insult variety of jokes.)Q: Why were the little drops of ink crying?A: Their mother was in the pen and they did not know how long her sentence would be.Submitted by Walter Lowe, aka "Anonymouse"Q: How many sheep does it take to make one wool sweater? A: I didn't even know sheep could knit!Q: What's a teacher's favorite nation?A: Expla-nation.Q: What's the most colorful state of U.S.A.?A: Color-ado.Submitted by Jeanine Padilha,BrazilQ: In what state does it cost the most to live in?A: Expennsylvania.Submitted by Mike McKinneyQ: What did the cannibal who was late for dinner get?A: The cold shoulder.Submitted by SeanA Christmas time joke for grammar classes:Q: What do you call Santa's helpers?A: Subordinate Clauses.Submitted by: MikeQ: What do you call a dog with no legs?A: Why bother, he won't come anyway.Q: How do you top a car?A: Tep on the brake, tupid!Submitted by Sandra DuncanQ: Is there a word in the English language that uses all the vowels including "y" ?A: Unquestionablely!Submitted by lisaQ: Why do birds fly south for the winter?A: Because it's too far to walk.Submitted by Kevin LongVocabulary Quiz:Q: What is the longest word in the English language? A: Smiles. (There is a mile between the first letter and the last letter.)Information Quiz:Q: What is the tallest building in our town?A: The library. (It has the most stories.)Submitted by Walter Lowe, aka "Anonymouse"Q: If you are Russian before you enter the bathroom and Finnish after you leave the bathroom, what are you when you are in the bathroom?A: European. (You're a-peein'.)Submitted by Cara Thompson (from my step-daughters)This riddle may be good for high-level science majors.Q: What do you call a test tube that graduates from high school?A: A graduated cylinderSubmitted by Margaret ElliottQ: How did Jonah feel after he got swallowed by a fish?A: Down in the mouth.Q: What did the monk say to the hotdog vendor?A: Make me one with everything.Submitted by Jason SchulteMaybe only appropriate for more mature students.Q: What did the fish say when he hit the wall?A: Dam!Submitted by: DuMarsQ: A man was locked in a room with only a bed, a calendar, and a piano. How did he drink, how did he eat, and how did he get out? Another man was locked in a room with only a mirror and a table. How did he get out? A third man was locked in an empty room. How did he escape?A: The first man drank from the springs of the bed, ate the dates off the calendar and played the piano until he found the right key, which he used to unlock the door. The second man looked in the mirror to see what he saw. Then he took the saw and cut the table in half. Next, he put the two halvestogether to make a whole. Finally, he crawled out through the hole. The third man broke out with the measles.Submitted by Walter Lowe, aka "Anonymouse"Q. What's brown and sticky?A. A stick!Submitted by Moira Dykes, Cambridge。
河南省九师联盟2024-2025学年高三上学期10月英语试题
河南省九师联盟2024-2025学年高三上学期10月英语试题一、阅读理解Ware Poets Open Poetry CompetitionWelcome! We’re pleased to announce the 26th annual Ware Poets competition. Since 1998, we’ve been devoted to offering poets a chance to resonate (共鸣) with our judges and win a prize. Entries are received from throughout the United Kingdom and abroad.Prizes: 1st prize: £600; 2nd prize: £300; 3rd prize: £150Rules and Instructions for Entry:● Th e competition is open to anyone aged 16 or over.● Poems should be in English and must not have been published either in print or online. They must not meanwhile be sent to other competitions or submitted for publication. They must be no longer than 50 lines.● Poems may be submitted:a. Either by post to The Competition Secretary, Ware Poets Competition, 25 Southbrook Drive, Cheshunt, Herts. , EN8 0QJ, using the Postal Entry Form. They must be typed or neatly handwritten on A4 paper. Each poem must be on a separate sheet of paper which must not bear your name.b. Or by email with the individual poems as either WORD or PDF attachments to w**********************.● Any number of poems may be submitted on payment of the proper fee, which is £5 per poem, or £13 for three poems and £4 per poem for more than three poems. If submitted by email, your submission will be admitted by email.● We regret that we’re unable to return poems, or allow corrections to be made after entry.● We’ll hold an informal prize-giving event and a reading event on the evening of Friday 13th September. Names of the prizewinners and winning poets will be published on our website at warepoets. org shortly after.● Copyright remains with the authors but Ware Poets reserves the right to print winning poems in the competition anthology (选集).1.What is a requirement for the entries?A.They should be 50 lines at least.B.They must be submitted by email.C.They have to be original works.D.They must be accepted by publishers. 2.How much should one pay to enter the competition with four poems?A.£13.B.£16.C.£18.D.£20.3.How will the winners benefit from the competition?A.Their works will be published.B.They can decide on the anthology.C.They can interview the judges.D.Their names will appear on a magazine.I was born in Mexico City, and raised in San Luis Potosi and Monterrey. I started learning how to cook by watching my mother and my grandmothers. My passion for cooking started at the age of 14 in Monterrey. Then, at age 17, I was contracted to work in New Orleans and cooked for three years. After that, I moved to Houston in 1990, where I fell in love and then had my first two beautiful children. We moved to Richmond in 1995 due to the unemployment of work in Houston.Living in Richmond, I saw many opportunities come up. I was one of the first ones in Richmond to open a food trailer (活动房屋) business on Jefferson Davis Highway in 2000. We were at this location for about two years, and then we decided to open a restaurant nearby on the same road towards the market. We moved to that location in 2007. Our business was going very well until my husband died, which forced us to close our restaurant.After sadly closing the business, I worked at Tio Pablo as the head cook. I was there for approximately 3 - 4 years, and then headed to Rancho T. I later started working a second job with Commercial Taphouse. After being with Taphouse from 2018, I worked until it closed in 2022. I then saw the opportunity to open my business again. I said to myself, “It’s time to reopen my business back up after so long. ”So now you can find me cooking seven days a week aboard my own food truck, El Taconazo, parked at 3227 Broad Rock Blvd. We have various dishes from tacos to hot, delicious soups like menudo on Sundays, and posole. Anyway, the traditional Mexican food I cook always attracts a crowd.I do my work with passion. I invariably give my 100% to ensure that my customers are happy and come back and visit us. My business may be small, but what makes it big is my happycustomers returning.4.What can we know about the author from paragraph 1?A.She got her first job at age 14.B.She grew up in Mexico City.C.Her family influenced her to cook.D.Her husband pushed her to move.5.What made the author shut down the restaurant on Jefferson Davis Highway?A.Her husband’s death.B.An offer from Tio Pablo.C.Her desire to expand.D.The depression of the market.6.What does paragraph 3 mainly talk about?A.Reasons for closing the business.B.Steps of reopening a restaurant.C.Restaurant industry’s expansion.D.The author’s working experience.7.What motivates the author to keep doing her work?A.Her increasing income.B.Her love of cooking.C.Her passion for eating.D.Her customers’ demand.Global travel is getting busier and busier, and this begs a question: Is there such a thing as an off-season anymore?Recently, ForwardKeys, a Spain-based travel data and analysis company, collected some numbers in three of the world’s most popular beach destinations: Thailand, Hawaii and the Maldives. Here’s the math: take the total number of tourists in a year and divide that figure by 12, which works out to an average of around 8% per month. Then, you can create a graph (图表) to see which months are higher or lower than that average.“In Thailand, low season typically lasts from April to September with April and May being really hot,” says Olivier Ponti, a director at ForwardKeys. “During this low season, the tourist volume each month covers over 7% of the annual total. That means very, very little seasonality.”Arguably, the biggest single factor affecting what we know as “peak season” travel is weather. A 2023 survey from the European Travel Commission reported that European travelers cited weather as their number-one factor in deciding where to go on vacation, with 8% of respondents saying they were concerned about extreme weather in European destinations.Climate may be an important factor in booking a holiday, but it’s not the only one. ForwardKeys’ Ponti, a father of two, notes that many travelers have to plan their trips at the sametime because they’re working around school schedules.But every family’s situation is different. For those whose kids are grown or who don’t have kids at all, there’re more opportunities to travel.Ann Woodward, a childfree American, makes a point of learning school schedules in her area so that she can plan around them. “I’m generally trying not to go to touristic attractions during those periods. I call it hiding,” she laughs. Woodward spent much of her youth traveling and has already checked off many of the big places that attract the most crowds, which means she can now go to less busy areas during an off-season. “For me, the challenge is about finding the joy in those low seasons,” she says.8.What does Olivier Ponti mean?A.Tourists find ways to fight overtourism.B.Off- season travel doesn’t exist anymore.C.More tourists enjoy traveling in low seasons.D.Peak-season travel is getting uncontrollable.9.What is the most important factor in European’s booking a holiday according to the 2023 survey?A.School plans.B.Economic budget.C.Technology.D.Climate.10.Why is Ann Woodward mentioned in the text?A.She is a travel enthusiast.B.She likes busier areas.C.She has flexible schedules.D.She has unique travel habits.11.What does the underlined phrase “checked off” in the last paragraph probably mean?A.Visited.B.Avoided.C.Examined.D.Remembered.If a stranger knocked on your door asking for using your phone, would you help? How about lending them five dollars for the bus, if they said they’d return and pay you back?Nowadays, many people find it hard to trust strangers. A recent study found that our ability to trust strangers may be more than just a social or psychological trait (特征) — it could be rooted in our DNA.This is important, as it turns out that trusting people might actually live longer and healthier lives compared to more skeptical people.Two main theories have appeared to explain why some people are more trusting than others. One suggests trust is a stable trait shaped by early life experiences. The other thinks it’s influenced by a person’s ongoing evaluation of the social environment. We can easily imagine that the answer to the question “Would you say that most people can be trusted? ” would depend on whether you’d been robbed the day before or if you’d had your dropped wallet returned.This is where the recent research comes in. A professor of Lund University, Edgerton and his coworkers have been doing research about trust. In their most recent study, involving 33, 882 Danish blood donors, their analyses identified a single gene (基因), PLPP4, which was strongly associated with the trait of trusting others. They discovered that the PLPP4 gene explained 6% of the variation in social trust within the study population. If you take two people who have similar education and life experiences, this gene alone could account for 6% of the difference in how much they trust others.They suspect that the PLPP4 gene may somehow soften our “fight-or-flight” survival mechanism. If our fight-or-flight system is less intense when we encounter new people, it makes sense that tending to trust others could have huge health benefits. Indeed, if trusting others acts as something against stress, it may lower the risk of cardiovascular (心血管的) disease.As people continue to uncover the mysteries of trust, one thing is clear: Understanding its genetic roots may hold the key to developing healthier communities in the world.12.What might affect people’s trust levels according to the existing theories?A.Their childhood habits.B.Their social experiences.C.Their personal abilities.D.Their communication skills.13.What does the recent study focus on?A.The ways to develop survival ability.B.The mental cause of trust.C.The connection between trust and a gene.D.The features of different genes. 14.What does the text say about trusting others?A.It could bring health benefits.B.It helps to develop the world faster.C.It lessens the intense stress in work.D.It causes better survival mechanisms. 15.What might be the best title for the text?A.Theories That Explain Why You Are TrustedB.Experiences Can Make You Grow DependableC.A Link Between Biology and Social ScienceD.A Gene Influences How Trusting You AreThanks to scientific and technological developments, billions of people today are living a better life than that of kings of centuries ago. 16 After all, despite all the progress we've made, the world faces many challenges in the 21st century: climate change, poverty and cancer, etc.Our best hope of dealing with these challenges is to make science and technology more productive. One practical way to achieve this is through the integration of Artificial Intelligence (AI) and laboratory automation. AI systems already possess superhuman scientific powers. They can remember massive volumes of facts and learn from huge datasets. 17 These powers are highly praised even by human scientists.18 Robots can now carry out most of the laboratory tasks humans can. Then there’re AI Scientists: AI systems integrated with laboratory automations that are capable of carrying out the closed-loop (闭环) automation of scientific research. These systems automatically generate hypotheses (假设) to explain observations, design experiments to test these hypotheses, interpret the results and then repeat the cycle.Within the last year or so, the world has been astonished by the success of Large Language Models (LLMs) like ChatGPT, which have achieved ground-breaking performance on a wide range of conversation- based tasks. 19 This is associated with their capacity to read all the scientific literature and act as a source of scientific knowledge.However, the application of AI to science has the potential for harm. As a step towards preventing this, some scientists have prepared the Stockholm Declaration on AI for Science.20 They urge all scientists working with AI to sign.A.They can carry out perfect logical reasoning.B.Today, laboratory automation is increasingly advancing.C.AI has the potential to transform the very process of thinking.D.These LLMs show great potential for super-charging AI Scientists.E.There’re now about 100 AI Scientists worldwide, working in various areas.F.However, it is deeply surprising how little appreciated this astonishing fact is.G.This commits the signees to the responsible and healthy development of AI for science.二、完形填空I carry the delayed dreams of my father firmly on my shoulders. People often looked 21 when they heard I 22 to be a lawyer, because that was my father’s dream when he was my age. They 23 me living my life for myself. What many people did not 24 was that there was no greater 25 for me than achieving what he had been unable to.About 17 years ago, I was born David Malakai Allen Ⅲ. I was named for my dad. This name, which now fills me with great pride and 26 , didn’t always do so. When I was younger, I often watched my father working at warehouses and driving trucks, which slowly 27 him down. I 28 to these with fear. I thought that giving me his name, my father had also handed me his 29 .One day in my freshman year of high school, my father told me that he knew from the moment when he 30 me for the first time that I was born to achieve something 31 . By naming me David Malakai Allen Ⅲ, he was 32 I was equipped with a resilient (不屈的) spirit.Now, with college enrollment (入学) only months away, I’m filled with pride 33 I’m the first person in my family who’ll graduate from college. When I was younger, the pressure of carrying my family’s legacy (遗赠) 34 felt tiring. As I’ve grown, I can 35 no greater blessing than achieving something those who came before me never thought possible for themselves.21.A.disappointed B.relieved C.surprised D.annoyed 22.A.desired B.happened C.failed D.refused 23.A.heard of B.insisted on C.objected to D.approved of 24.A.confirm B.doubt C.receive D.realize 25.A.strength B.energy C.honor D.method 26.A.motivation B.kindness C.trend D.space 27.A.turned B.wore C.calmed D.put 28.A.attended B.contributed C.reacted D.pointed29.A.rule B.future C.secret D.target 30.A.forgot B.saved C.approached D.held 31.A.similar B.relaxing C.great D.demanding 32.A.ensuring B.warning C.admitting D.debating 33.A.expecting B.knowing C.regretting D.stressing 34.A.eventually B.instantly C.formally D.really 35.A.imagine B.waste C.overlook D.research三、语法填空阅读下面短文,在空白处填入1个适当的单词或括号内单词的正确形式。
english jokes
Some scientists decided to do the following experiments on a dog.For the first experiment, they cut one of the dog's legs off, then they told the dog to walk. The dog got up and walked, so they they learned that a dog could walk with just three legs.For the second experiment, they cut off a second leg from the dog, then they told the dog once more to walk. The dog was still able to walk with only two legs.For the third experiment, they cut off yet another leg from the dog and once more they told the dog to walk. However, the dog wasn't able to walk with only one leg.As a result of these three experiments, the scientists wrote in their final report that the dog had lost it's hearing after having three legs cut off.Submitted by:Idrissi Mouhssine--------------------------------------------------------------------------------What is the longest word in the English language?SMILES: there is a mile between the first and last letters!"Submitted by: Kevin Penner--------------------------------------------------------------------------------Teacher: Maria please point to America on the map.Maria: This is it.Teacher: Well done. Now class, who found America?Class: Maria did.Submitted by: Kmankoolman--------------------------------------------------------------------------------A Scotsman who was driving home one night, ran into a car driven by an Englishman. The Scotsman got out of the car to apologize and offered the Englishman a drink from a bottle of whisky. The Englishman was glad to have a drink."Go on," said the Scot, "have another drink."The Englishman drank gratefully. "But don't you want one, too?" he asked the Scotsman. "Perhaps," replied the Scotsman, "after the police have gone."Submitted by: Ugur Yavuzturk--------------------------------------------------------------------------------A: Aren't you wearing your wedding ring on the wrong finger?B: Yes I am, I married the wrong woman.Submitted by: Anonymous--------------------------------------------------------------------------------A man was pulled over for driving too fast, even though he thought he was driving just fine.Officer: You were speeding.Man: No, I wasn't.Officer: Yes, you were. I'm giving you a ticket.Man: But I wasn't speeding.Officer: Tell that to the judge! (The officer gives man the ticket.)Man: Would I get another ticket if I called you a jerk?Officer: Yes, you would.Man: What if I just thought that you were?Officer: I can't give you a ticket for what you think.Man: Fine, I think you're a jerk!Submitted by: Nick Henry, ESL teacher in Korea--------------------------------------------------------------------------------What are the three quickest ways of spreading a rumour (or gossip). •Telegram•Telephone•Tell a womanPerhaps not very politically correct in the times we live in, but worth a slight chuckle. Submitted by: Dave & BrendanEDITOR'S NOTE: Maybe you could teach your students the phrase "politically correct" and discuss it.--------------------------------------------------------------------------------If you give a man a fish, he eats for a day.If you teach a man to fish, he can always eat.If you give a man a fire, he's warm for a day.If you light a man on fire, he is warm for the rest of his life.Submitted by: Anonymous--------------------------------------------------------------------------------A: Did you hear that a baby was fed on elephant's milk and gained twenty pounds in a week.B: That's impossible. Whose baby?A: An elephant's.Submitted by: Ugur Yavuzturk--------------------------------------------------------------------------------"Am I the first man you have ever loved?" he said."Of course," she answered "Why do men always ask the same question?".Submitted by: Ugur Yavuzturk--------------------------------------------------------------------------------When I was young I didn't like going to weddings.My grandmother would tell me, "You're next"However, she stopped doing that after I started saying the same thing to her at funerals. Submitted by: Chris Fisher--------------------------------------------------------------------------------A: I'm in a big trouble!B: Why is that?A: I saw a mouse in my house!B: Oh, well, all you need to do is use a trap.A: I don't have one.B: Well then, buy one.A: Can't afford one.B: I can give you mine if you want.A: That sounds good.B: All you need to do is just use some cheese in order to make the mouse come to the trap.A: I don't have any cheese.B: Okay then, take a piece of bread and put a bit of oil in it and put it in the trap.A: I don't have oil.B: Well, then put only a small piece of bread.A: I don't have bread.B: Then what is the mouse doing at your house?!Submitted by: Genti Biraci--------------------------------------------------------------------------------A very drunk man comes out of the bar and sees another very drunk man.He looks up in the sky and says, "Is that the sun or the moon?"The other drunk man answers, "I don't know. I'm a stranger here myself."Submitted by: Anonymous--------------------------------------------------------------------------------A man is talking to God.The man: "God, how long is a million years?"God: "To me, it's about a minute."The man: "God, how much is a million dollars?"God: "To me it's a penny."The man: "God, may I have a penny?"God: "Wait a minute."Submitted by: Freshteh Sadeghi--------------------------------------------------------------------------------Fred is 32 years old and he is still single.One day a friend asked, "Why aren't you married? Can't you find a woman who will be a good wife?"Fred replied, "Actually, I've found many women I wanted to marry, but when I bring them home to meet my parents, my mother doesn't like them."His friend thinks for a moment and says, "I've got the perfect solution, just find a girl who's just like your mother."A few months later they meet again and his friend says, "Did you find the perfect girl? Did your mother like her?"With a frown on his face, Fred answers, "Yes, I found the perfect girl. She was just like my mother. You were right, my mother liked her very much."The friend said, "Then what's the problem?"Fred replied, "My father doesn't like her."--------------------------------------------------------------------------------An elementary school teacher sends this note to all parents on the first day of school."If you promise not to believe everything your child says happens at school, I will promise not to believe everything your child says happens at home.Submitted by: Willaim Greaves--------------------------------------------------------------------------------A: Doctor, will I be able to play the piano after the operation?B: Yes, of course.A: Great! I never could before!Submitted by: Fred--------------------------------------------------------------------------------Why couldn't Cinderella be a good soccer player?She lost her shoe, she ran away from the ball, and her coach was a pumpkin.(Requires basic knowledge of the Cinderella story and that both ball and coach have double meanings.)Submitted by: Jillian H.--------------------------------------------------------------------------------Teacher: Tell me a sentence that starts with an "I".Student: I is the...Teacher: Stop! Never put 'is' after an "I". Always put 'am' after an "I".Student: OK. I am the ninth letter of the alphabet.Submitted by: Monirul Hassan--------------------------------------------------------------------------------Two factory workers are talking.The woman says, "I can make the boss give me the day off."The man replies, "And how would you do that?"The woman says, "Just wait and see." She then hangs upside-down from the ceiling.The boss comes in and says, "What are you doing?"The woman replies, "I'm a light bulb."The boss then says, "You've been working so much that you've gone crazy. I think you need to take the day off."The man starts to follow her and the boss says, "Where are you going?"The man says, "I'm going home, too. I can't work in the dark."Submitted by: Tshifhiwa Rambau--------------------------------------------------------------------------------Two cows are standing in a field.One says to the other "Are you worried about Mad Cow Disease?"The other one says "No, It doesn't worry me, I'm a horse!"Submitted by: Michael Trew--------------------------------------------------------------------------------Teacher: How can we get some clean water?Student: Bring the water from the river and wash it.Submitted by: Zeinab Eltayb--------------------------------------------------------------------------------Q. What do you call a ginger bread man with one leg?A. Limp Bizkit. (limp biscuit)(Alternate: What do the British call a cookie that got wet?)Submitted by: Emily Mileski(If you don't know what Limp Bizkit is, see the results of a Google search for Limp Bizkit.)--------------------------------------------------------------------------------A guy says to his friend, "Guess how many coins I have in my pocket."The friends says, "If I guess right, will you give me one of them?"The first guys says, "If you guess right, I'll give you both of them!"Submitted by: Matty--------------------------------------------------------------------------------This is a good one to follow the following previously submitted joke.A: What do you call a deer with no eyes?B: No idea. (No Eye Deer.)A: What do you call a dead deer with no eyes?B: Still no idea.--------------------------------------------------------------------------------A: Meet my new born brother.B: Oh, he is so handsome! What's his name?A: I don't know. I can't understand a word he says.Submitted by: Landa Eugene--------------------------------------------------------------------------------Q: When does the (English) alphabet have only 25 letters?A: At Christmas time, because it is the time of Noel. (No L)Submitted by: George Hurlburt--------------------------------------------------------------------------------Q: What starts with E, ends with E and only has one letter?A: An envelope.--------------------------------------------------------------------------------Q: If you drop a white hat into the Red Sea, what does it become?A: Wet.--------------------------------------------------------------------------------Q: What do you call a boomerang that won't come back?A: A stick.--------------------------------------------------------------------------------Q: Where do you find giant snails?A: On the ends of their fingers.(Giants' nails.)--------------------------------------------------------------------------------Q: What travels around the world and stays in a corner?A: A stamp.--------------------------------------------------------------------------------Q: What is white when it's dirty and black when it's clean?A: A blackboard.--------------------------------------------------------------------------------These need to be written.Q: What do you call a pig with three eyes?A: A piiig.Q: What goes Oh, Oh, Oh?A: Santa Claus walking backwards.--------------------------------------------------------------------------------Q: What do elephants have that no other animal has?A: Baby elephants.--------------------------------------------------------------------------------Depending on where you live, students will enjoy this one.Q: What do you call a hippie's wife?A: Mississippi.--------------------------------------------------------------------------------Q: What did the ocean say to the beach?A: Nothing, it just waved!Submitted by: Eric Stein--------------------------------------------------------------------------------The First 3 Years of Marriage•In the first year of marriage, the man speaks and the woman listens.•In the second year, the woman speaks and the man listens.•In the third year, they both speak and the neighbors listen.--------------------------------------------------------------------------------A man inserted an 'ad' in the classifieds: "Wife wanted".The next day he received a hundred letters. They all said the same thing: "You can have mine."--------------------------------------------------------------------------------Love is one long sweet dream, and marriage is the alarm clock.。
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Scenario-Specific Topology Reduction in Network SimulationsJournal:International Symposium on Performance Evaluation of Computerand Telecommunication SystemsManuscript ID:SPECTS-05-NTS-012.R1Topic Area:Networking and Telecommunication SystemDate Submitted by the26-May-2005Author:Complete List of Authors:Petit, Barath; Georgia Tech, College of ComputingAmmar, Mostafa; Georgia Tech, College of ComputingFujimoto, Richard; Georgia Tech, College of ComputingKeywords:scalable simulation , topology reductionScenario-Specific Topology Reduction in Network Simulations1Barath Petit(bpetit@)Mostafa Ammar(ammar@)Richard Fujimoto(fujimoto@)College of Computing,Georgia Institute of TechnologyAtlanta,GA30332USAAbstractOur current ability to perform packet-level simulations of large-scale networks is limited by factors such as processing speed and memory resources.Many approaches have been proposed to reduce the complexity of simulation models in a manner that reduces the computing resources required while preserving thefidelity of the simulation.In this paper we con-sider topology reduction as a means to reduce the resource re-quirements of network simulations.We show that it is possi-ble to reduce topologies of simulation models while preserving certain classes of metrics.We do this in the particularly chal-lenging environment where closed loop traffic(e.g.,TCP)is being simulated in the network.The reductions are scenario specific in the sense that the desired performance metrics of a network simulation experiment dictate the feasibility of partic-ular reduction methods.We use a set of experiments represent-ing simulation scenarios to demonstrate our approach.1IntroductionCurrent communication networks are extremely complex making theoretical analysis difficult or impossible.The bulk of the complexity lies in the often vast number of interacting agents including protocols,traffic sources and routers.Thus, simulation is the only recourse for the analysis of large net-works.Simulation of packet switched networks involves the modelling of every packet in the network.Packet level sim-ulation requires many events and thereby simulation of large scale networks is very resource intensive in nature.Thus,our current ability to simulate large networks is limited by fac-tors such as processing speed and memory resources.Reduc-ing simulation runtime often involves reducing the number of events to be processed.A reduction in model size of the simulation directly translates to speeding up of the execution times.Reducing the topology of the simulation would lead to a decrease in the number of hops to be traversed by a packet thereby yielding a savings in the number of packet events.Further,the memory requirements are also reduced.In[4]the authors list various methods for reducing Internet topologies with the objective of preserving the graph-theoretic properties.The methods are essentially traffic and topology independent and,thus,it is not clear that preserving graph-theoretic properties would indeed preserve the experimental outcomes of the network simula-tions.In order to demonstrate the importance of bandwidth awareness in topology reduction,we perform the following experiment.We removed some of the bottleneck links of the 1This work is supported in part by NSF under contract number ANI-0136936topology of one of our experiments(to be described in section 5)and compared the results of the simulation run of the re-duced topology with the results obtained by running the sim-ulation on the original topology.In this case the outcome of interest is the response time distributions of the webflows. As seen infigure1,the results do not match.Present approaches to reduce simulation complexity pertain to traffic reduction[1]or abstraction of the simulation model[3].However,reducing the topology to be simulated(to reduce simulation cost)while preserving the traffic properties and metrics(in the context of TCP/IP traffic)has proven to be difficult.As will be elaborated in section3,the difficulty in reducing the topology owes much to the closed-loop nature of transport protocols employed in current communication net-works.It is inherently difficult to characterize traffic from closed-loop sources since this requires prior knowledge of measures such as packet loss ratios.The difficulty further in-creases in direct proportion to the number of bottleneck links in the network.On the other hand it has been shown in[4] that it is possible to remove high capacity nodes in an ATM network,while preserving queuing behavior at the low capac-ity nodes that are retained.In this paper we show that it is possible to reduce topologies of networks when the traffic is closed-loop in na-ture with the caveat that only certain classes of metrics are preserved as a result of the reduction.Thus,the reductions are scenario-specific since the metrics to be observed dictate the feasibility of the reduction method.We define the reductions to be scenario-specific because unlike current schemes whose feasibility is determined by the traffic in the network and net-work parameters,our methods’feasibility is dictated by the scenario or more specifically the performance measures to be determined.The outline of the paper is as follows.In section2 we present related work on approaches to reduce simulation complexity.We elaborate on the model reduction framework and a classification of network simulation scenarios in section 3.We list our topology reduction methods in section4.We present the applicability of the reduction methods on three example scenarios in section5with a discussion of the results in section6.We conclude the paper with directions for future work in section7.2Related WorkCurrent approaches to reducing run-time of simulations are hinged on abstracting or reducing some aspects of the simulation.For example,recently approaches have been sug-(a)Simulation Outcome:Original Response TimeDistribution (b)Simulation Outcome:After Removal of BottlenecksFigure1:Sensitivity of Response Time Distributions to Bot-tlenecksgested to reduce simulation run-time by scaling down the traf-fic fed to the simulator while keeping the network topology untouched[1].In addition to the traffic,the network parame-ters such as link capacities and buffers are scaled by the cor-responding factor but the number of nodes in the network remains unchanged.However,SHRINK[1]does not work for DropTail schemes in certain scenarios and its behavior in scenarios where the network composition is diverse remains unclear.Similarly RSM[2]scales down only the network pa-rameters while leaving the network traffic and topology un-touched.We have also observed that while RSM[2]preserves to some extent packet-level metrics such as queuing delay and link utilization,it fails forflow level metrics.Another approach includesfluid simulations[3]that seeks to determine network characteristics by solving a set of closely coupled differential equations.Fluid simulation methods model packet transfer asfluidflows.Thus,each connection is assumed to have a certain amount offluid to be transferred across the network.Event processing is required only when thefluid transfer is initiated or terminated and intermediate events that involve change of rate offluid transfer.Thus,thefluid abstraction obviates the necessity of simulating every single packet.Thefluid approach leads to event reduction in scenarios where network topology is moderate and dynamicity of traffic is limited.However,in cases where the topology is large or the traffic is dynamic the event rate exceeds that of the packet level simulation.This is due to the fact that dynamic traffic scenarios involve frequent rate change events when the transfer rate of aflow needs to be changed to accommodate a newflow arrival/departure or buffer overflow at the links.A rate change event at a link can trigger multiple rate changes in downstream links.This problem is exacerbated in large networks.This is referred to as the’ripple’effect[3]and is one of the main limitations of fluid simulations.It is notable thatfluid simulations are not scalable with respect to heavy web traffic and are not suitable for packet-level metrics.Note that the reduction methods dis-cussed above cannot be applied to the simulation scenarios considered in this paper.More specifically,fluid simulation techniques fail to preserve packet-level measures and are prone to ripple effects(described above)in face of heavy web traffic.Similarly,as discussed above,SHRiNK does not apply in scenarios where routers employ the DropTail scheme and RSM fails forflow-level measures.3Model Reduction FrameworkA simulation experiment can be thought to be consisting of three main aspects viz.the topology,traffic and outcome.If the topology is a router-level topology then other factors such as the queuing scheme at the links come into play as well.The outcome of the experiment could be values or distributions of specific metrics or relative ordering among various metrics among others.3.1Fine and Coarse Grained MetricsDefining a metric as a measure that is a function of the traffic and topology of the simulation experiment,we could classify metrics asfine-grained or coarse-grained.Some examples offine-grained metrics are packet-level metrics in a packet switched network such as the end-end delay(per packet), queuing delay and buffer occupancy at the routers.Some ex-amples of coarse-grained metrics are:•Response time distributions of webflows in a network with long-lived TCPflows as background traffic•The distribution of response times,number of customers in servers in Content Delivery Networks(CDN),anycast delivery network scenarios.•The query response time,rate of QueryHits in a Gnutella P2P network.•Server metrics of web servers withfinite job buffers3.2Open and Closed Loop TrafficWith the aim of reducing router-level topologies,we classify metrics relative to the traffic used in the simulation experi-ment.Thus,the traffic would dictate the feasibility of re-duction methods relative to the particular metric but the de-gree of reduction would be dictated by the topology.Within the context of the Internet we classify the traffic as closed-loop(elastic)and open-loop(inelastic).Before delving fur-ther,we outline the issues involved in reducing a topology for the above two traffic classes with respect to the corresponding metrics.First we consider the open-loop traffic scenario.Prime examples are ATM networks with voice/video traffic.It is possible to characterize the traffic as a function of time for open-loop scenarios.For example,the traffic could be char-acterized by its peak rate or the envelope.It is possible to reduce these networks and still preservefine-grained metrics such as buffer overflow probability or buffer length distribu-tion.In[5]the authors demonstrate that in a network of ATM buffers fed with open-loop traffic removal of upstream nodes with high service rates leaves the queuing behavior at down-stream nodes unchanged.However,it is not possible to apply the same to a closed-loop traffic based network.For example,we con-sider now the case of closed loop traffic where the traffic is controlled by TCP-like congestion control algorithms.In these cases it is non-trivial to obtain traffic estimate with-out the prior knowledge of measures such as drop proba-bility and round trip time.Furthermore,under this regimesources modify their sending rates in response to network conditions.Thus,unlike the above case it is non-trivial to reduce the topologies while preservingfine-grained metrics such as throughput offlows,packet loss ratio and buffer oc-cupancy at the routers.3.3Simulation Scenario ClassesWith the above as background we now move on to classify simulation experiments into four main classes.The classifica-tion will be based on traffic and observable metrics assuming that we are dealing with router level topologies.•Class1scenario consists of open-loop traffic cases.As pointed out in the discussion above,it is possible to re-duce these networks while maintaining thefidelity offine-grained metrics.Thus,the range of observable metrics under topology reduction includes bothfine-grained and coarse-grained metrics(since we expect coarse-grained metrics to hold in the face offine-grained metrics’fidelity).•Class2scenario consists of networks that use closed-loop traffic and metrics to be observed arefine-grained like packet-level metrics.•Class3scenario consists of networks that use closed-loop traffic but the metrics to be observed are coarse-grained be-sides being relatively insensitive to the closed-loop nature of the system.•Class4scenario consists of networks that use a mixture of closed-loop and open-loop traffic.The observable metrics here are not only coarse-grained metrics butfine-grained metrics pertaining to the open-loop traffic as well.The classification of simulation scenarios is summarized in Table1.The classification also applies to QoS centric exper-iments.For example,if the metric of interest is an end-to-end packet delay bound determined as a function of link utiliza-tion,then assuming TCP based traffic,this experiment falls under class2scenarios.However,if the experiment pertains to evaluation of an admission control scheme based on the number offlows then this experiment will fall under class 3scenarios.Similarly if the experiment pertains to packet scheduling schemes then since packet-level detail is central to the experiment,it falls under either class1or class2sub-ject to the input traffic being TCP or open-loop.Reduction methods for class1scenarios include[5] and[6].To the best of our knowledge there are no known reduction methods covering class2,3and4scenarios.Reduction methods for class2scenarios are non-trivial.The method would have to preservefine-grained met-rics such as packet level details.One plausible approach could be thefixed point approximation approach,whereby we aim to reduce the topology while preserving the operat-ing point of the network.However,applying this approach seems non-trivial for networks with more than one bottleneck link[7].In this work,we list several methods of topology re-duction for class3and4scenarios as per the above classifi-cation.To preserve thefidelity of these metrics we reduce the topology represented by a graph G(V,E),where V is the set of all nodes of the topology and E is the set of all the links in the topology to a reduced graph G(V ,E )where|V|>|V |and|E|>|E |.Table1:Classification of network simulation experimentsTraffic Observable metricsClass1Open-loopfine-grained,coarse-grained Class2Closed-loopfine-grainedClass3Closed-loop coarse-grainedClass4Closed-loop coarse-grainedand open-loop andfine-grained(wrt open-loop traffic)4Model Reduction MethodsIn this section,we outline different methods of reducing the topology of the network.We maintain the following invari-ants while reducing the topology.•The addition of a new link in the topology should not in-duce a new bottleneck.•The total propagation delay encountered by a packet of aflow remains unchanged.Notation We use the following notation while describingthe algorithms.•Flows belonging to the same source destination pair are classified as belonging to the same class.•P(l)={S,N1,N2,...,D}is the sequence of nodes tra-versed by the class l where S,D are the source and desti-nation nodes.•C(m,n):capacity of the bidirectional link between nodesm,n•S l(N i):for any node N i∈P(l),N i=S,D we refer toN i−1as entry point of l through N i represented by S l(N i)•D l(N i):for any node N i∈P(l),N i=S,D,N i+1is referred to as the exit point of l through N i represented byD l(N i).•C n:represents the set of allflows passing through node n.•L n:for a given node n we define the set L n as L n={m:m=S l(n)∀l∈C n}•R n:for a given node n we define set R n as R n={k:k=D l(n)∀l∈C n}•I x:For each node x of the set R n for a given node n,wedefine the set I x={m: l∈C n s.t m=S l(S l(x))}.I x represents the set of nodes that haveflows coming into x through n.•M x: i∈I x C(i,n)•Throughout the reduction process,we denote the nodes thathave been removed as marked.A set of nodes,all of whose members have not been removed is referred to as being not marked.Method-1We remove a node from the topology if the out-bound capacity exceeds the inbound capacity.The network is rewired by adding the propagation delays of the removed links.The new link has its capacity as the minimum of the previous two capacities and it’s link cost(used by the routing algorithm)is the sum of the previous two link costs.Before removing node n,we verify that the existing bottlenecks for the nodes in R n,L n are unchanged.In effect,we are remov-ing links that induce negligible queuing delay.Thus,remov-ing these nodes would have minimal effect on the class3and 4scenario metrics.We remove nodes only if for allflows passing through the node,the inbound capacity is exceeded by the outbound capacity.More formally,method-1can be described by the following pseudo-code.for each n∈V doif L n,R n not marked∧L n R n=∅thenfor each x∈R n doif M x>C(n,x)thenbreakif n’s removal modifies bottlenecks of R n,L nthenbreakfor each l∈C n doC(S l(n),D l(n))=C(S l(n),n)Add propagation delaysModify link costsRemove n and all incident linksAdd newly formed linksMark n as markedMethod-2Since class3and4scenario metrics are insensi-tive to topology reductions,reduction of the capacity of new links to be added should not induce much distortion either. The reduced capacity on the other hand results in reduced number of packet events to be processed.Now let C1and C2be the inbound and outbound capacity of aflow through a node n and C2≥C1.We apply the same method as in method-1to determine if a node n is to be removed.Then wereplace the new link’s capacity by C=(11+12)−1and it’slink cost(used by the routing algorithm)is the sum of the pre-vious two link costs.This results in the new node providing the same transmission delay per packet as the previous two nodes in succession.As in method-1,the propagation delay of the new link is the sum of the delays of the links that it replaced.We apply this method as long as the new link does not induce a new bottleneck in the topology.The reduction in number of packet events is inversely proportional to capacity of the new link.Thus,since C<C1and C<C2,the method is likely to yield more reduction in terms of numbers of events to be processed.As will be seen below,the reduction in the number of events is reflected in the loss of throughput of the long-lived closed-loop traffic.More formally,method-2can be described by the following pseudo-code.for each n∈V doif L n,R n not marked∧L n R n=∅thenfor each x∈R n doif M x>C(n,x)thenbreakfor each l∈C n doC lef f=(1C(S l(n),n)+1C(n,D l(n))−1if C lef fmodifies bottlenecks of R n,L n thenbreakfor each l∈C n doC(S l(n),D l(n))=C lef fAdd propagation delaysModify link costsRemove n and all incident linksAdd newly formed linksMark n as markedWe examine the sensitivity of packet level metrics (class2scenarios)to the reduction methods described above. In a scenario where TCP long-livedflows share the network with webflows,the throughput of one of the long-lived TCP flows was observed to be1.032Mbps.After the removal of a single node(via method-2described above),a difference of13%was observed in the throughput.After a removal of another node by method-2,the difference in throughput increased to27%.This reinforces the applicability of these methods to class3and4scenarios only.4.1Reduction methodologyThe reduction methodology is illustrated infigure2.We use the ns-2simulation script to extract the topology parameters. The parser processes the script and populates the data struc-tures such as the adjacency matrix.In addition,the cost and delay matrices are also populated with the entries correspond-ing to the link costs(used by the routing algorithm)and the propagation delays of the links.These matrices,next-hop routing matrix and the traffic specification(source-destination tuples)are used by the reduction algorithm to mark edges and nodes for removal as detailed in the pseudo-code for method-1and method-2.Note that we assumeflat routing i.e.,there is no hierarchical routing.This is necessary to ensure that the reduction algorithm preserves the propagation delay of each path in the topology.PARSERextract topologyADJACENCY MATRIXCOST MATRIXDELAY MATRIXns−2scriptextract next−hop matrix NEXT−HOPMATRIXREDUCTIONMETHOD(method−1,method−2)ns−2 scriptfor reducedtopologysource−destinationtuplesFigure2:Reduction Methodology5Class3and Class4ScenariosWe elaborate on the effectiveness of the above reduction methods while dealing with class3and4scenarios.We con-sider three example scenarios noting that the metrics of inter-est are relatively insensitive to the the closed-loop nature of background traffic.The background traffic for all the scenar-ios consists of long-lived TCPflows.The scenarios are:•Scenario A:This is a class3scenario where we study the response times of web requests.•Scenario B:This is a class3scenario where we study web servers with limited job buffers.The metric of interest is the response time distributions.•Scenario C:This is a class4scenario where we consider UDP sources in a network with background TCP traffic. The metric of interest is average one-way packet delay. 5.1The TopologyWe use the GT-ITM topology generator[8]to generate a2420 node topology with3442links.We use the transit-stub model to generate the topologies.The router buffers of the links employ the DropTail policy.The propagation delay of the links were assigned uniformly in the range of10ms to50ms. The bandwidth of the links were uniformly assigned in the range of1Mbps to500Mbps.The foreground traffic consists of HTTPflows and the background traffic consists of long-lived TCPflows.The web traffic(for scenarios A and B) is generated using the webtraf module of the ns-2network simulator.The foreground traffic for scenario C consists of UDP exponential on/off sources.5.2Scenario A:Web trafficWe study a scenario,where we are interested in the response times of the web requests in a network.In order to gener-ate traffic for the experiment,1000source-destination pairs were chosen randomly.We refer to each of these source-destination pairs as aflow.The endpoints of eachflow were designated as the server and the client.The background traf-fic consists of100,000long-lived TCPflows.For eachflow, the requests for web objects is assumed to be Poisson at the rate of20per second.The size distribution for the requests is heavy-tailed with mean3packets and shape parameter1.2. Results We compare the response time distributions of original(unscaled)and reduced simulation runs by employ-ing the Kolmogorov-Smirnov test[9].The level of signifi-canceαis assumed to be0.05.While checking for the accep-tance of the null hypothesis that the empirical distributions are the same,we also observe the value of the D-statistic. Note that the D-statistic gives us the absolute maximum dif-ference in the empirical cumulative distribution functions of the samples.We list the results in Table2andfigures3and 4.The run-time results correspond to10seconds of simula-tion time.As seen from Table2,the application of the re-duction methods distortes the mean response times by0.45% (for method-1)and0.62%(for method-2).The low values of the D-statistic indicate that the response time distributions obtained from the reduced topology simulation runs match the original response time distributions.This is reflected in figures3and4,where the response time distribution obtainedby each method is superimposed against the original response time distribution.The difference in average response times of individualflows(between the original average response timeof theflow and average response time of theflow in the scaled simulation)was also observed.The empirical probability dis-tribution of the difference in average response time of eachflow for method-1is depicted infigure5.Fromfigure5,we observe that most of theflows experience a distortion of less than3%in the average response times.Table2:Scenario A:ResultsUnscaled Method-1Method-2 Mean response time(ms)1762.191754.641751.05 D-statistic N.A0.01660.0191 Simulation Run-time(secs)459003560032400 00.0050.010.0150.020.0250.030.0350.040.04501020304050607080 ProportionofflowsResponse time (50ms units)"unscaled""method-1"Figure3:Scenario A:Response time distribution-Method1 00.0050.010.0150.020.0250.030.0350.040.04501020304050607080 ProportionofflowsResponse time(50ms units)"unscaled""method-2"Figure4:Scenario A:Response time distribution-Method25.3Scenario B:Servers withfinite job queuesIn scenario A,the web servers had zero processing overhead.In this section,we consider servers which inducefinite pro-0.050.10.150.20.250.30.350.40.450.502468101214161820P r o p o r t i o n o f f l o w sRelative Difference in Avg. Response times (%)"Scenario-A"Figure 5:Scenario A:Relative Difference in Response Times cessing delay for every incoming request,the delay being de-pendant on the size of the request.This entails a job buffer at the servers.Note that this queue resides at the application level and the processing latency of the server will depend on the CPU speed of the server.We denote the processing rate of the server by C expressed in packets per second.Thus,a request of sizeb packets entails a processing time of bC secs.The size of the job buffer is denoted by B .An incom-ing request is enqueued if there is no buffer overflow.The request’s response time is the sum of the queuing time,the processing latency and the transfer latency of the web object across the network.The acceptance ratio is defined as the ra-tio N −N dNwhere N is the total number of requests which ar-rive at the servers and N d denotes the number of requests that are dropped due to buffer overflow at the job queue.Clearly factors such as B ,C and the distribution of the input arrival stream of the requests affect metrics such as distribution of response times and the acceptance ratio.As in scenario A,we pick 1000flows randomly and each flow is assigned a server and client.The background traffic consists of 100,000long-lived TCP flows.The arrival rate for the requests for the web objects was assumed to be Poisson at the rate of 20per second.The size distribution for the requests is heavy-tailed with mean 3packets and shape parameter 1.2.The values of the parameters were B =10and C =220.Results We list the results in Table 3and figures 6and 7.The run-time results correspond to 10seconds of simulation time.As seen from Table 3,the distortion induced in the av-erage response times and the acceptance ratios on the appli-cation of method-1and method-2is minimal.Similarly,the low value of the D-statistic for method-1and method-2is re-flected in figures 6and 7.The difference in average response times of individual flows (between the original average re-sponse time of the flow and average response time of the flow in the scaled simulation)was also observed.The empirical probability distribution of the difference in average response time of each flow for method-1is depicted in figure 8.From figure 8,we observe that most of the flows experience a dis-tortion of less than 3%in the average response times.Table 3:Scenario B:ResultsUnscaled Method-1Method-2Mean response time(ms)1889.651885.671881.66D-statistic N.A 0.01240.0123Acceptance Ratio 0.6040.5890.585Simulation Run-time(secs)4680032400316800.0050.010.0150.020.0250.030.0350.040.04501020304050607080P r o p o r t i o n o f f l o w sResponse time (50ms units)"unscaled""method-1"Figure 6:Scenario B:Response time distribution -Method 15.4Scenario C:UDP SourcesIn this scenario,we consider a set of UDP sources with expo-nential on-off traffic.The mean on and off times were 10ms and 90ms respectively.We observe that topology reduction applied via method 1preserves the mean one way per-packet delay.We consider two cases where the rate of each of the sources during ON time are 20Mbps and 100Mbps.The experiments included 1000ON/OFF sources with the back-ground traffic consisting of 1000long-lived TCP flows.We present results for method-1only since results for method-2were not satisfactory.0.0050.010.0150.020.0250.030.0350.040.04501020304050607080P r o p o r t i o n o f f l o w sResponse time(50ms units)"unscaled""method-2"Figure 7:Scenario B:Response time distribution -Method 2。
18个喜闻乐见的分手故事
18个喜闻乐见的分手故事18 Horrifying Breakup Stories That Will Make You Glad You’re Single喜闻乐见的18个分手故事1. Submitted by Abby Morris (Facebook)1、Abby MorrisI dated a guy for a few months. One day, he stopped returning my texts/calls. He told me he was having “family trouble” and couldn’t talk. This went on for a few days until I found out the real reason he wasn’t talking to me: He was waiting for his breakup postcard to arrive in my mailbox. That’s right. He broke up with me via postcard. A POSTCARD.我和一个家伙交往了几个月。
有一天,他不再回我的短信和电话。
他告诉我他有“家庭问题”,所以不想说话。
几天后我发现他只是不跟我说话:他在等我收到他寄的分手明信片。
没错,他通过一张明信片来跟我分手。
一张明信片。
2. Submitted by meghans43902c5752、meghans43902c575We had dated for a while and talked about getting married. After a couple months of future planning we decided to go look at rings. The next night after looking at rings, he showed up at my house, knocked on the door, gave me a hug and kiss, looked deep into my eyes, and said, “I think we should break up.”我们交往了一段时间,都谈婚论嫁了。
Submitted By
INTERNATIONAL SPACE STATION ELECTRIC FIELD MEASUREMENT PACKAGE (EFMP)Final Technical ReportReport No. A-5508FContract No. H-28501D20 January 1998John K. DaherMark L. WheelerSubmitted To:NASA/MSFCProcurement OfficeAttn: GP24M/Glynda H. MeeksMarshall Space Flight Center, AL 35812Phone: 205-544-0422Fax: 205-544-9080E-Mail: glynda.meeks@Submitted By:Electromagnetics and Antennas DivisionSensors and Electromagnetic Applications LaboratoryGeorgia Tech Research InstituteGeorgia Institute of TechnologyAtlanta, GA 30332Contracting Through:Georgia Tech Research CorporationAtlanta, Georgia 30332TABLE OF CONTENTS1.INTRODUCTION (1)1.1Background (1)1.2Program Scope and Objectives (1)2.KICKOFF MEETING AT NASA/MSFC (2)3.ELECTRIC FIELD MEASUREMENT REQUIREMENTS DEFINITION (3)3.1The United States Space Surveillance Network (3)3.2ISS Orbital Parameters (3)3.3Frequency Range/Resolution Requirements (6)3.4Sensitivity Requirements (6)3.5Dynamic Range Requirements (6)3.6Sensor/Antenna Performance Requirements (6)3.7Resolution Bandwidth Requirements (7)3.8Electric Field Sampling and Data Recording Rates (8)3.9Number of Orbits Required to Collect the Data (9)3.10Summary of Electric Field Measurement Requirements (10)4.ELECTRIC FIELD MEASUREMENT AND RECORDING TECHNOLOGYASSESSMENT (12)5.ALTERNATE EXPERIMENTAL CONCEPT EXPLORATION (15)6.INTERFACE REQUIREMENTS DEFINITION (17)7.QUALIFICATION REQUIREMENTS DEFINITION (19)8.PREFERRED MEASUREMENT PACKAGE CONCEPT SELECTION (21)9.IMPLEMENTATION PLAN PREPARATION (22)10.REFERENCES (23)APPENDIX A........................................................................................................................A-1 APPENDIX B.........................................................................................................................B-1 APPENDIX C – IMPLEMENTATION PLAN.......................................................................C-1PREFACEThe work described in this report was performed by personnel within the Electromagnetics and Antennas Division (EAD) of the Sensors and Electromagnetic Applications Laboratory (SEAL) of the Georgia Tech Research Institute (GTRI). This task was sponsored by the National Aeronautics and Space Administration / Marshall Space Flight Center (NASA/MSFC) under Basic Ordering Agreement NAS8-97089, Contract No. H-28501D. This task was monitored by Mr. Tony Clark of NASA/MSFC. The described work was directed by Mr. John K. Daher, Project Director, under the technical supervision of Mr. David P. Millard, Chief of EAD. This report summarizes the activities and results of a concept study for an electromagnetic field measurement package (EFMP) to be flown on the International Space Station (ISS).ACKNOWLEDGEMENTSThe authors are most grateful for the overall direction and technical support provided Mr. Tony Clark of NASA/MSFC. The authors would also like to acknowledge the helpful information and documentation provided by the following individuals: Mr. Mark Chavez and Mr. Nicholas L. Johnson of Johnson Space Center (JSC), Dr. Sid Sdriharan of Massachusetts Institute of Technology/Lincoln Laboratory, Mr. Paul Gilbert and Mr. Lowell Primm of NASA/MSFC, Mr. Cesar Gimenez and Mr. Mark Estes of Boeing Defense & Space Group, and Mr. Taft Devere, Unites States Space Command.1.INTRODUCTION1.1BackgroundThe current radiated susceptibility test specification limit for ISS payloads is as low as 5 V/m over portions of the test frequency range [1]. Electromagnetic environmental analyses have predicted that on-orbit field strength levels, due to ground-based emitters, can be as high as 250 V/m. An Electric Field Measurement Package (EFMP) is required to determine, through experiments, the validity of these predicted levels. Validation of the on-orbit field levels will determine whether or not an increase in the radiated susceptibility test specification limits for ISS payloads is warranted.1.2Program Scope and ObjectivesThe purpose of this study was to develop an implementation plan for a flight experiment on the International Space Station (ISS) to measure the on-orbit electric field environment. The EFMP experiment will: (1) provide accurate measurement of the on-orbit electric field environment across the applicable frequency range of significant ground and ISS transmitters;(2) provide publishable measurement results and data for U.S. military and commercial spacecraft and payload developers; (3) be compatible with interface requirements (such as size and power) for an ISS external payload attach site; and (4) meet the applicable qualification requirements of ISS attached payloads. To accomplish these program objectives, the concept study consisted of the following eight tasks:Task 1: Attend Kickoff Meeting at NASA-MSFCTask 2: Define Electric Field Measurement RequirementsTask 3: Assess Electric Field Measurement and Recording TechnologyTask 4: Explore Alternate Experimental ConceptsTask 5: Define Interface RequirementsTask 6: Define Qualification RequirementsTask 7: Select Preferred Measurement Package ConceptTask 8: Prepare Implementation Plan2.KICKOFF MEETING AT NASA/MSFCOn 26 August 1997, GTRI and NASA/MSFC personnel met in Huntsville, AL. The meeting consisted of the following: (1) technical discussions related to the desired performance of the EFMP; (2) an overview presentation of the EXpedite the PRocess of Experiments to Space Station (EXPRESS) pallet system for external payloads; (3) a brief discussion of the proposed Environmental Monitoring Package (EMP); and (4) a review of proposed program tasks/ schedule for the EFMP Concept Study. NASA personnel also provided GTRI engineers with an informal tour of their EMI test facilities and ISS assembly areas, as well as reference documentation.During technical discussions, NASA personnel provided GTRI with the ISS orbital parameters including the inclination, altitude (minimum and nominal), and orbital period. NASA personnel also indicated that they are particularly interested in verifying the on-orbit field levels produced by UHF and C-Band emitters that are part of the Space Surveillance Network (SSN). This would require the measurement package to provide frequency information (at a minimum for these two bands). The desired configuration for the system is to mount the antenna/sensors externally. However, if necessary, there is an earth-pointing window on the ISS through which an internally mounted antenna could be pointed. The EXPRESS pallet system is being developed to modularize all external payloads for ease of implementation. EXPRESS pallet discussions focused on size and electrical interface constraints for a modularized EXPRESS pallet payload. Also, NASA is developing an Environmental Monitoring Package (EMP) payload for the ISS. It was initially recommended that the possibility of integrating the Electric Field Monitoring Package with the EMP should be explored. However, it was later learned that the conceptual payload design for the EMP was due 1 September 1997. Therefore, if the integration with the EMP takes place, it will have to be done as part of the pre-planned product improvements (P3I) program.During the meeting, GTRI obtained a number of documents [2-8] that proved to be very useful in completing the various tasks on this program. Finally, it is noted that NASA personnel were in complete concurrence with the proposed program plan for the EFMP Concept Study and had no recommended changes to the proposed program tasks or schedule.3.ELECTRIC FIELD MEASUREMENT REQUIREMENTS DEFINITIONThe objective of this task was to determine fundamental design requirements for the EFMP. The EFMP design requirements consist of the following: (1) frequency range/resolution;(2) sensitivity; (3) dynamic range; (4) sensor/antenna performance; (5) electric field sampling rate; (6) electric field data recording rate; and (7) number of orbits required to collect the requisite data. It is important that that the system design requirements be tailored to optimize the measurement of the expected on-orbit electric field environment. Therefore, as part of this task, GTRI reviewed the relevant documentation [9,10] to determine the expected ISS on-orbit electric field environment. Reference 9 defines the expected electric field environment produced by terrestrial emitters for orbital ranges of 100 to 2,000 nmi. Reference 10 contains RF output power data for transmitters that will be located on-board the ISS and the shuttle orbiter. The design requirements for the EFMP were based primarily on the predicted electric field environment as specified in these reports.During the program kickoff meeting at NASA/MSFC, NASA personnel stated that the primary goal of the EFMP is to measure the field levels produced at the ISS orbital altitude by terrestrial emitters and that measuring field levels from ISS on-board transmitters are of lower priority. Thus, the data in Reference 9 was of primary interest for this task. In particular, the worst-case field strength plot contained in Reference 9 (page A-10) for a 200 nmi orbit was used as a guide for defining the desired frequency range/resolution, sensitivity, and dynamic range requirements for the EFMP. The data in the Reference 10 was used to determine the frequency range and power levels of on-board transmitters. NASA is particularly interested in measuring the field levels produced by radars that comprise the U.S. Space Surveillance Network (SSN). 3.1The United States Space Surveillance NetworkThe mission of U.S. SSN is to detect, track, catalog, and identify all man-made objects in space [9]. The network is comprised of dedicated, collateral, and contributing sensors distributed about the earth. The primary mission of dedicated sensors is to support the SSN in maintaining the catalog of artificial satellites and supporting a host of space operations. Although the primary mission of collateral sensors, which include 12 major radars, is ballistic missile attack warning and/or intelligence gathering, these sensors actually provide a significant share of U.S. space surveillance observations. Finally, contributing sensors are owned and operated by other Agencies but provide space surveillance data under special agreements or contracts. The radars which comprise the U.S. SSN are listed in Table 1 [9,12]. According to Reference 12, the transmit polarization for these radars are all either linear (typically vertical) or right-hand-circular (RHC).3.2ISS Orbital ParametersThe ISS will orbit the earth at a nominal altitude of approximately 200 nmi (150 nmi minimum altitude) and an inclination of approximately 51.6°. The nominal orbital period is 90 minutes. SSN radar site locations along with typical orbital ground tracks for a 90 minute orbital period and a 60° orbital inclination are shown in Figure 1 [9]. The contour lines in the figure represent line-of-sight intercepts for a 200 km altitude (line-of-sight coverage for the 200 nmiTABLE 1. UNITED STATES SPACE SURVEILLANCE NETWORK RADARS [9,12]FREQ. BAND SENSORTYPE SYSTEM LOCATIONOPAGENCYOPFREQ.(MHz)ALT.1AZIMUTHALCOVERAGE(deg)SSNCATEGORYVHF Interfer-ometer NAVSPASUR CONUS(32.6N,243.OE)(33.4N.,253.0E)(33.3N,266.4E)(33.1N.,269.0E(32.3N,276.5E)(32.0N,278.1E)USN217LEOHEO90,270DEDICATEDVHF DISHRADAR ALTAIR ROI-NAMUR IS.(09.4N,167.5E)USA153-162LEO0-360CONTRIBUTINGUHF DISHRADARBMEWS II(AN/FPS-92)ALASKA(64,3N,210.SE)USAF400-450LEO0-360COLLATERALUHF DISHRADAR ALTAIR ROI-NAMUR IS.(09.4N,167.5E)USA415-440LEOHEO0-360CONTRIBUTINGUHF PHASEDARRAYRADARBMEWS I(AN/FFPS-120)GREENLAND(79,6N,291.7E)USAF420-450LEO0-360COLLATERALUHF PHASEDARRAYRADARBMEWS III(AN/FPS-126)ENGLAND(54.4N,359.3E)RAF420-450LEO0-360COLLATERALUHF PHASEDARRAYRADAREGLIN(AN/FPS-85)CONUS(30,6N,273.8E)USAF NA LEOHEO120-240DEDICATEDUHF PHASEDARRAYRADARPARCS(AN/FPQ-16)CONUS(48.7N,262.1E)USAF NA LEO298-3600-078COLLATERALUHF PHASEDARRAYRADAR PAVE PAWS E(AN/FPS-123)CONUS(41.8N.289.5E)USAF420-450LEO347-3600-227COLLATERALUHF PHASEDARRAYRADAR PAVE PAWS W(AN/FPS-123)CONUS(39.1N,2387.6E)USAF420-450LEO126-3600-227COLLATERALC DISHRADAR ALCOR ROI-NAMUR IS.(09.4N,167.5E)USA5664-5672LEO0-360CONTRIBUTINGC DISHRADARANTIGUA(AN/FPQ-14)ANTIGUA IS.(17.1N,298.2E)USAF5400-5900LEO0360CONTRIBUTINGC DISHRADAR ASCENSION(ANFPS-15)ASCENSION IS.(07.9N298.2E)USAF5400-5900LEO0-360COLLATERALC DISHRADARKAENAPOINT(AN/FPQ-14)HAWAII(21.6N,201.7E)USAF5400-5900LEO0-360COLLATERALL DISHRADAR MILLSTONEHILLCONUS(42.6N,288.5E)MIT1295LEOHEO0-360CONTRIBUTINGX DISHRADAR HAYSTACKLRIRCONUS(42.6N,288.5E)MIT10000LEOHEO0360CONTRIBUTINGKu DISHRADARHAYSTACKAUXILIARYRADAR (HAX)CONUS(42.6N,288.5E)MIT16,700LEOHEO0-360CONTRIBUTING Note 1:LEO = Low Earth Orbit HEO = High Earth OrbitISS orbital altitude would be somewhat larger). A 10 degree minimum elevation angle is assumed for the ground radars.3.3Frequency Range/Resolution RequirementsThe frequency range requirement is defined to be 100 MHz to 18 GHz. The lower frequency range requirement of 100 MHz is selected to enable detection of Russian space surveillance radars, many of which operate in the VHF band. The frequency range requirement covers all emitters of interest in the Reference 9 except the 35 and 95.5 GHz instrumentation radars located at Roi-Namur in the Marshall Islands. It is GTRI's judgment that: (1) very few EMI problems are generated by millimeter wave emitters due to the high susceptibility thresholds of electronic devices and the small coupling cross-sections of receptors at these very short wavelengths and (2) a measurement package design that included these Ka and W-Band frequencies would be cost prohibitive when compared with the limited additional data that would be collected at these bands.3.4Sensitivity RequirementsThe sensitivity requirement is defined to be 2 V/m. The 2 V/m system sensitivity level is considered an adequate lower limit for detecting field levels that will be of interest. Currently all ISS payloads must meet a minimum radiated susceptibility test requirement of 5 V/m [1]. Thus, the 2 V/m measurement package sensitivity level will allow adequate margin for evaluating this payload susceptibility limit in the ISS operational environment.3.5Dynamic Range RequirementsThe minimum dynamic range requirement is defined to be 42 dB. Based on Reference 8, the highest expected field strength at 200 nmi is approximately 250 V/m. With a desired sensitivity of 2 V/m, the minimum dynamic range requirement is readily calculated to be 42 dB (i.e., 20log[250/2]). Additional dynamic range would provide for greater signal detection capability and additional flexibility in the design of the measurement package. Dynamic range is limited on the high end by possible saturation and damage of the receiver front end. The low end of the dynamic range is primarily limited by antenna sensitivity and receiver noise figure.3.6Sensor/Antenna Performance RequirementsThe remaining design requirements (sensor/antenna performance, frequency resolution, electric field sampling rate, electric field data recording rate, and number of orbits required to collect data) will vary depending on the measurement technique that is used to implement the measurement package system. Sensitivity, dynamic range, and frequency resolution requirements make the use of a frequency scanning superheterodyne receiver (e.g., a spectrum analyzer) an attractive measurement instrument. Therefore, it is reasonable to determine the sensor/antenna performance, frequency resolution, electric field sampling rate, electric field data recording rate, and number of orbits requirements assuming an implementation of this type of measurement system.The antenna factor (AF) requirement is specified to be 31–70 dB/m. To allow for design flexibility, this AF specification is to include any cable losses or external attenuation between the antenna and the receiver input. Antenna factor, which is defined as the ratio of the incident field strength to the induced antenna voltage, is a convenient parameter for use in specifying the antenna performance. The minimum AF of 31 dB/m was determined based on the maximum anticipated field strength (250 V/m) and the maximum allowable input level to the receiver (typically 1 W or approximately 7 V into 50 Ω). The maximum allowable AF of 70 dB/m was determined from the sensitivity requirements of the EFMP. Broadband antennas with AFs in the 30-70 dB/m range will have sufficiently broad beamwidths to cover the solid angle subtended by the earth's surface at a 200 nmi orbit.Appendix A contains a Mathcad® model which was developed to calculate the maximum allowable AF (and, equivalently, the minimum required antenna gain) to meet the measurement sensitivity requirements. Inputs to the model include the following: the frequency range and the number of points to be used for the calculations; the total amount of RF attenuation (both internal and external); the receiver IF bandwidth and noise figure; the antenna temperature; the minimum signal-to-noise ratio (S/N); the minimum electric field sensitivity; and the coaxial cable parameters (length, geometry, dielectric constant and power factor, and conductor material parameters). Based on the 2 V/m sensitivity requirement and a typical worst-case spectrum analyzer noise level of -61 dBm (as measured for an HP 8566B spectrum analyzer with a resolution bandwidth of 3 MHz); the AF could not exceed 70 dB to maintain a minimum S/N of 10 dB. Again, the 70 dB/m AF specification includes any RF cable losses or external attenuation between the antenna and the receiver (e.g., as seen in Appendix A, with 10 dB of cable loss, the AF could not exceed 60 dB/m).The optimum antenna solution to ensure coverage of all incident signal polarizations (i.e., eliminate polarization mismatch losses for all possible signal polarizations) is to use dual, orthogonally polarized antennas. Examples include a dual polarized, log-periodic dipole array or one RHCP and one left-hand-circularly polarized (LHCP) conical log spiral antenna. The total field level can be determined by performing separate measurements for each polarization and then appropriately adding the orthogonal polarization electric field components (i.e., calculating the square root of the sum of the squares) as part of the post-measurement data calibration process.3.7Resolution Bandwidth RequirementsThe EFMP should at the least have sufficient frequency resolution to discriminate between emissions in broad frequency bands of interest (e.g., as a minimum, upper VHF, lower UHF, L, S, C, X, and Ku bands). The majority of the SSN radar systems operate in the lower UHF band (400-450 MHz) or C-Band (5400-5900 MHz). Measurement of field levels in these two frequency bands should therefore be given a high priority in the design of the EFMP. Better frequency resolution (on the order of a few MHz) is highly desirable. However, narrowing the frequency resolution beyond this point will reduce measurement sensitivity and accuracy when measuring signals from narrow pulse width emitters.Most of the high power emitters of interest are pulsed radars. Based on the data contained in NASA Contractor Report 4776, the pulse repetition frequencies (PRFs) and pulsewidths for these radars are in the ranges of 0.1 to 400,000 pulses per second and 0.03 to 50,000µs, respectively. The goal of the measurement system is to measure the peak field level of these radars. If the impulse bandwidth of the receiver is greater than the reciprocal of the pulsewidth of the radar signal, then the receiver will detect the peak amplitude of the pulse. For narrower impulse bandwidths, the peak response of the receiver is a function of the product of the pulse width and impulse bandwidth. Under these conditions, the amplitude reduction of the detected signal level in dB relative to the actual peak pulse level is approximated by:where:L p = amplitude loss in dB;τ = pulsewidth of the measured signal; and B i = impulse bandwidth of the receiver.For spectrum analyzers that specify 6 dB resolution bandwidths, the resolution bandwidth is nearly equal to the impulse bandwidth. Thus, the amplitude loss can be made to equal zero if the product of the pulsewidth and resolution bandwidth can be made to be greater than or equal to one. The maximum resolution bandwidth for typical spectrum analyzers is in the range of 3MHz. Thus, peak field levels for radars with pulsewidths greater than 0.33 µs can be detected without significant loss. All but seven of the emitters surveyed in the NASA Contractor Report 4776 have pulsewidths greater than 0.33 µs. Resolution bandwidths greater than about 5 MHz result in little improvement in pulse response for the emitters of interest while reducing the frequency measurement accuracy and the receiver sensitivity to continuous wave (CW) or long pulse width signals. Resolution bandwidths much less than 1 MHz result in degraded pulse response. Thus, the recommended resolution bandwidth is 3 MHz.3.8Electric Field Sampling and Data Recording RatesIn the calculations of receiver frequency scan rates, it is assumed that the ISS (and thus the receiver) is being tracked by the terrestrial radar. One approach to sampling the electric field strength from these pulsed radars with a scanning receiver is to scan in frequency slow enough to insure that no pulses go undetected. This approach will be called the “slow scan” approach. If the resolution bandwidth requirement is set at 3 MHz, the required electric field sampling rate (expressed as the inverse of the spectrum analyzer’s sweep time) can be calculated. The majority of the radars surveyed in the NASA Contractor Report 4776 have PRFs greater than 100 Hz.Thus, the equivalent pulse repetition interval is 0.01 s or less. To ensure that signals with pulse repetition intervals less than 0.01 s (PRFs greater than 100 Hz) are detected by the scanning spectrum analyzer, the time that any given frequency is within the passband of the resolution filter must be at least 0.01 s. Thus, the corresponding sweep time constraint can be expressed as:where:L B p i =⋅⋅20log()τ (1)ST SRBW PRF r ≥⋅min (slow scan approach) (2)ST = receiver sweep time (time for full sweep);SR = receiver sweep range (frequency band over which the receiver sweeps);BW r = receiver resolution bandwidth; andPRF min = minimum radar pulse repetition frequency.Covering the 100 MHz to 18 GHz frequency range requires a total SR of 17.9 GHz (which with an HP 8566B spectrum analyzer would require four sub-bands having bandwidths of 100 MHz to 2.5 GHz; 2.5 GHz to 5.8 GHz; 5.8 GHz to 12.5 GHz; and 12.5 GHz to 18.0 GHz). With the spectrum analyzer resolution bandwidth set at 3 MHz; the minimum scan time that would be required to ensure that all pulsed signals with PRFs greater than 100 Hz are detected is approximately 60 s. However, sampling two orthogonal electric field polarizations with a single receiver will require a total frequency scan time of approximately 120 s. Thus, approximately 1/120 Hz or 8.3 millihertz (mHz) will be defined as the maximum electric field sampling rate. If a faster sampling rate is required for particular sub-bands (e.g., during particular portions of the orbit), the scan range for those particular sub-bands can be reduced. In this way, the measurement package would have the capability to scan narrow sub-bands to accommodate the efficient collection of data for specific emitters of interest. The electric field data will likely be stored to an electronic file at the completion of each scan. Thus, the data sampling rate (for all frequencies in each band) will have a maximum rate of somewhat less than 8.3 mHz (allowing for overhead time of approximately 1 second to store each trace corresponding to an orthogonal field polarization). For minimum sampling rate specifications, we will select a minimum electric field sampling rate and a minimum data sampling rate of 8 mHz.An alternate approach, which we will call the “fast scan” approach, would be to use the “MAX HOLD” feature of the spectrum analyzer to display the maximum detected amplitudes from a number of sweeps using a relatively fast sweep rate before storing the trace. With this approach, radar pulses could be missed if the ST is a harmonic or a sub-harmonic of the radar pulse repetition interval (1/PRF). Thus, the STs would have to be carefully selected and/or multiple STs would have to be used on alternate scans to insure a high probability-of-intercept (POI). (Note that an intercept becomes a detection only if the intercepted signal strength exceeds the detection threshold sensitivity of the receiving system.) With the fast scan approach, the electric field sampling rate would be significantly higher than the slow scan approach outlined above. However, the data sampling rate would likely be comparable to that of the slow scan approach since a number of frequency scans would have to be made to ensure an acceptably high POI. A Mathcad® model that calculates the measurement time required to achieve a desired POI using the fast scan approach is provided in Appendix B.3.9Number of Orbits Required to Collect the DataBased on a nominal 90 minute orbital period, successive ground tracks will be separated by approximately 22.5 degrees in longitude (see Figure 1). With an orbital inclination of 51.6 degrees and a 200 nmi orbital altitude, all SSN emitters with latitudes between approximate 65 degrees N and 65 degrees S should be able to have line-of-sight (LOS) visibility to the ISS. Of the 17 radars that make up the U.S. SSN, only one (BMEWS I) will not have LOS visibility to the ISS.SSN radar metric observations include time, elevation, azimuth, range, and possibly range rate [10]. Three to five metric observations are typically made per track and six to ten seconds are typically required per metric observation. Thus, track times are expected to be in the 18-50 second range. As detailed in Section 3.7, spectrum analyzer scan times of approximately 60 seconds per polarization (or 120 seconds total for two orthogonal polarizations) are required to scan the entire 100 MHz to 18 GHz frequency range. However, spectrum analyzer scan times can readily be reduced below 18 seconds while still ensuring intercept of radar pulses by narrowing the scan frequency range about the known operating frequency of the tracking radar. Also, longer track times could presumably occur provided that special arrangements are made in advance. In either case, if the ISS is tracked by a SSN radar, it can be assumed that electric field data can be collected from that SSN radar.According to Reference 10, standard procedure for tracking the ISS would consist of at most a single SSN radar track per orbit (provided LOS visibility exists). Furthermore, without special arrangements being made, it is likely that certain SSN assets would be used to track the ISS more often than other assets. For example, all else being equal, UHF phased array radars would likely be the asset of choice (in favor of UHF or C band dish radars) due to the higher achievable data rates. With 16 radars in the U.S. SSN with LOS visibility to the ISS and without special arrangements being made to ensure that specific assets are used to track the ISS, an inordinately high number of orbits would be required to ensure that all SSN radar emissions are characterized. Thus, it is assumed that special arrangements will be made in advance of the experiment to allow for tracking of the ISS with specific radars during specific times and orbits and, if desired, tracking of the ISS by more than one SSN radar in a single orbit. Assuming that these prior arrangements will be made and allowing for the possibility of some orbits in which the ISS will not be visible to a SSN radar or will only be visible to a radar which has already be characterized, it is estimated that a minimum of about 10 orbits will be required to characterize the emissions from the SSN. A greater number of orbits are desirable to provide better statistical data on SSN radars and other emitters.3.10Summary of Electric Field Measurement RequirementsThe EFMP design requirements defined under this task are summarized below (sampling rates based on slow scan approach):(1) Frequency Range: 100 MHz to 18 GHz(2) Sensitivity (min): 2 V/m(3) Dynamic Range (min): 42 dB (2 V/m – 250 V/m)(4) Antenna Factor (including cable losses and external attenuation): 31 - 70 dB/m(5) Resolution Bandwidth (nom): 3 MHz(6) Electric Field Sampling Rate (min): 8 mHz(7) Data Sampling Rate (min): 8 mHz(8) Number of Orbits (min): 10These design requirements are idealized requirements that have been defined to guide the design of the measurement package system. Based on the analyses performed under this task, it is believed that these design requirements are adequate to meet the baseline objectives of the experiment and are achievable with commercial off-the-shelf (COTS) hardware. However, it。
PPAP填写说明(提交给伟创力的PPAP如何填写)
2. Shifted mold:
Supplier provides the samples and FAI/PPAP report to Flex ASQE;
中文解释 图纸编号 零件名称。 版本编号参见flex 图纸 提交文件编号 模号或穴号 材质或材料规格 检验者 检验日期,月/日/年 格式 审核者 填写测量实际数据 关键尺寸
12
PPAP Instruction
Sheet C : CPK(制程能力指数)
注意:
1.至少32pcs样品实际测量值!! 2.CPK值须≥1.5,CP值须≥2.0!!
Reviewed By: PPAP提交之前的审核人。 Supplier Comments: 供应商注释或建议 Submission Reason 提交原因(只能填选一种)
Initial Submission 首次提交 Engineering Change(s) 工程变更
Tooling: Transfer, Replacement, 模具搬迁更换,翻新等
Sheet B: FAI (首件样本尺寸检查)
注意: 1. FAI中的Location要求必须对应图纸中所有尺寸所处位置填写, 例如: D5, A2, C3……; 2. FAI中CTF尺寸是指图纸中的重点管控尺寸(即Cpk尺寸), 若图纸要求是Cpk尺寸 的就必须选择Yes, 否则不需要填写. 因此有CTF尺寸的就必须做CPK与GR&R分析. 3. 在FAI sheet 输入正负公差时不需要加上正负号, 否则后面的公式无效. 4.
会议记录英语范文10篇
会议记录英语范文10篇 Meeting Minutes Template 1。
Meeting Title: Project Status Update.Date: March 15, 2023。
Time: 10:00 AM 12:00 PM.Location: Conference Room A.Attendees:John Smith (Project Manager)。
Mary Jones (Developer)。
Bob Brown (Designer)。
Jane Doe (Tester)。
Agenda:1. Project Overview.2. Project Status Update.3. Discussion on Project Challenges.4. Next Steps.Minutes:1. Project Overview.John Smith opened the meeting by providing an overview of the project, including its goals, scope, and timeline.2. Project Status Update.Mary Jones presented the current status of the project. She reported that the development team had completed 75% ofthe coding and 50% of the testing.Bob Brown provided an update on the design phase. He confirmed that the design was finalized and was being implemented.3. Discussion on Project Challenges.The team discussed several challenges that had arisen during the project, including:Delays in receiving feedback from stakeholders.Technical issues with the software.Unforeseen changes in project requirements.4. Next Steps.The team agreed on the following next steps:Prioritize fixing the technical issues with thesoftware.Schedule more frequent meetings with stakeholders to provide updates and receive feedback.Monitor the changing project requirements and make necessary adjustments.Meeting Adjournment:The meeting was adjourned at 12:00 PM.Minutes Submitted by:Jane Doe (Tester)。
英语绕口令
Listen to the Teacher(to the tune of "Twinkle, Twinkle, Little Star")Students, students, look this way.Listen to what I will say.Fold your hands and sit up straight.Please be quiet as you wait.Students, students, look this way.Listen to what I will say.Ailing Auntie Annie Ames ate apple butter in abundance.The big fat cat sat on the rat. (Repeat 3x)(submitted by Brian T. from Texas)The rain in Spain falls mainly on the plain.(Thanks to Brian T. from Texas for this submission from "My Fair Lady") Double bubble gum bubbles double. (submitted by Elisabeth from Brazil) Betty Botter had some butter,"But," she said, "this butter's bitter.If I bake this bitter butter,it would make my batter bitter.But a bit of better butter--that would make my batter better."So she bought a bit of butter,better than her bitter butter,and she baked it in her batter,and the batter was not bitter.So 'twas better Betty Botterbought a bit of better butter.Billy blows big blue bubbles.Barber baby bubbles and a bumble bee(submitted by Tracy Paul Feyereisen)Baby boy blue blows bubbles.(submitted by Toniann DeFusco)Busy buzzing bumble bees.A big black bug bit a big black bear,Made the big black bear bleed blood.(submitted by Jacqui Phillips)Captain Kangaroo's carefully crunching crunchy candy corn.Chris crashes crimson cars quickly.A cup of proper coffee in a copper coffee cup.(submitted by Robin Keith)How much wood would a woodchuck chuckif a woodchuck could chuck wood?He would chuck, he would, as much as he could,and chuck as much wood as a woodchuck wouldif a woodchuck could chuck wood.How much woodWould a woodchuck chuckIf a woodchuck could chuck wood?He'd chuck all the woodThat a woodchuck couldIf a woodchuck could chuck wood.(submitted by Byron Stuckless)A cheap sheep is cheaper than a cheap ship.(submitted by Anne-Cécile Couderc)The cheeky Chief Chef Chicken chatted to the Second Chef Chicken as he cooked.(submitted by Derrell Thomas)Chubby Chuck got chubby cheeks.(submitted by Andrea)Chipp couldn't chop chocolate chips 'cause Chip chipped his chocolate chip chopper.(submitted by Madu Bodinagoda)If one doctor doctors another doctor, does the doctorwho doctors the doctor doctor the doctor the way thedoctor he is doctoring doctors? Or does he doctorthe doctor the way the doctor who doctors doctors?Dazzling dinosaurs dance, dance, dance."Ed's easily excited," excitedly exclaimed Edwina.Eddie eats eight eggs easily every evening.(submitted by Nguyen Quoc Viet)A flea and a fly flew up in a flue.Said the flea, "Let us fly!"Said the fly, "Let us flee!"So they flew through a flaw in the flue.Funny Frank fell fifty feet.Four fluffy feathers and a fiffer feffer feff(submitted by Tracy Paul Feyereisen)Fresh fried fish,Fish fresh fried,Fried fish fresh,Fish fried fresh.Of all the felt I ever felt,I never felt a piece of feltwhich felt as fine as that felt felt,when first I felt that felt hat's felt.Fe Fi Fo Fom --Tell me quickly where you're from.(anonymous submission)Greek grapes.Grandma gathers great green grapes.Gray geese graze in the green, green grass.George and Grace grew glossy grapes and grimy garlic gladly. (submitted by Janet Kidon)In Hartford, Hereford and Hampshire, Hurricanes Hardly Hever Happen. (Thanks to Brian from "My Fair Lady.")Harry helped Hailey hold the hot pot. (Repeat 3x.)Inchworms itching.Icabod is itchy; so am I.(submitted by Tracy Paul Feyereisen)Jackie's jumping jovially 'round Jakarta.Chubby jugglers juggling oranges jovially.Jumping Jacky jeered a jesting juggler.Did Jumping Jacky jeer a jesting juggler?If Jumping Jacky jeered a jesting juggler,Then where is the jesting juggler that Jumping Jacky jeered?(submitted by Ameeta)Red leather, yellow leather. Red leather, yellow leather.Red lorry, yellow lorryRed lorry, yellow lorryRed lorry, yellow lorry(submitted by Andrew Johnston)Note: ("Lorry," for those who don't know, is the British English word for the American English "truck.")Really leery, rarely Larry.Round the rugged rock, the ragged rascal ran.Raleigh, are you already ready?Are you really ready, Raleigh?Raleigh's really ready, Riley.Riley, Raleigh's already ready!Rubber baby buggy bumpers,Rubber baby buggy bumpers,Rubber baby buggy bumpers.(submitted by Valerie Brown-Wood)Lucy and Lacy love lemon lollipops.Little Lola Lopp licked a lollipop.(submitted by Tracy Paul Feyereisen)A real weird rear wheel. (Repeat 3x)(submitted by Jason Morgan)Rory, the Romanian rural warrior-ruler rip roared as he rested on his horses' real rear posterior wrongly.(submitted by Derrell Thomas)Rory and Rupert warriors and Roger the worrier were all really reared wrongly in a rural brewery.(submitted by Derrell Thomas)Might might make right.Momma made me mash my M & M's.(submitted by Robin Keith)Moose noshing much mush.Nine new noisy, nosy, annoying neighborsNine nervous Nuns in an Indiana Nunnery.(submitted by Robin Keith)Nine new neckties and a nightshirt and a nose(submitted by Tracy Paul Feyereisen)Noisy knobbly kneed gnomeHad nine nice niecesWho knocked nine times,On a nutty knotty knocker.The nine nice nieces were known to be naughty,For eighty one knocksOn a nutty knotty knockerIs a noisy niecy nutty knotty knocker knock(submitted by James Corr)Naive Nanna Nancy needed no nickname.(submitted by Nguyen Quoc Viet)You know New York.You need New York.You know you need unique New York.(submitted by Doug Nelson)Orange jello, lemon jello,Orange jello, lemon jello,Orange jello, lemon jello.Peter Piper picked a peck of pickled peppers.Did Peter Piper pick a peck of pickled peppers?If Peter Piper picked a peck of pickled peppers,where's the peck of pickled peppers Peter Piper picked?Poppa, Poppa picked a pot of peas.(submitted by Robin Keith)Pirates' private property(submitted by Catherine Quinto)Push, pull. Push, pull. Push, pull.(submitted by Brianna)Plead Lee's pleas for peas, please!(submitted by Lee the Lemon)Quaint queens can't quarrel crazily.Queenie is quite quiet, but quick-witted.(submitted by Fong Chee)The sixth sick sheik's sixth sheep's sick.She sells sea shells by the sea shore.(submitted by Donna Caddie)Seven slippery sea- snakes slithered past the shore. (submitted by Kathy Donaghey)Sister Suzie sewing shirts for soldiersSuch skill at sewing shirtsOur shy young sister Suzie showsSome soldiers send epistlesSay they'd rather sleep in thistlesThan the saucy, soft short shirts for soldiers Sister Suzie sewsSal sang seven silly songs.Sally sells sea shells by the sea shore. But if Sally sells sea shells by the sea shore then where are the sea shells Sally sells?Slender skiers slammed into sleek smugglers.(submitted by Rose Richman)Scandalous scouts scaled a scaffold.(submitted by Rose Richman)Students scribbled on scruffy sneakers.(submitted by Rose Richman)Skillful skaters skidded and slammed against a big stone slab.(submitted by Rose Richman)Stodgy students study static structures.(submitted by Rose Richman)Squirmy squirrels swim in slosh.(submitted by Rose Richman)I vigorously sheared the swift smelly silly sheep on the sweet swell sheep swift ship.(submitted by Derrell Thomas)Sixty six sick chicks are stuck in the stock room full of sixty six sticks. (submitted by Francis Joshua Calabia)Sailor Sam saw some swallows swooping suddenly.(submitted by Nguyen Quoc Viet)The sailor thought his ship was sinking,such thoughts no sailor should be thinking.(submitted by Dieter Wolters)One smart fellow, he felt smart.Two smart fellows, they felt smart.Three smart fellows, they all felt smart. (Repeat 3x.)(submitted by Donna Hoult)Susie sells sea shells by the sea shore.(submitted by Brian T. from Texas)Moses supposes his toes-es are roses, but Moses supposes erroneously. Moses, he knows-es his toes-es aren't roses, as Moses supposes his toes-es to be.(Thanks to Brian T. from Texas for this submission from "Singing in the Rain.")The sixth sheik's sixth sheep is sick.She sees Shem shake.A cheap sheep is cheaper than a cheap ship.(submitted by Anne-Cécile Couderc)The three trees(submitted by Lisa Cyr)Not these things here but those things there.(submitted by Dan)King Thistle stuck a thousand thistles in the thistle of his thumb.A thousand thistles King Thistle stuck in the thistle of his thumb.If King Thistle stuck a thousand thistles in the thistle of his thumb,How many thistles did King Thistle stick in the thistle of his thumb?Ruth and Luther's moose's loosest tooth is uncouth.(submitted by Norma Jean Krim)I can think of six thin things, but I can think of six thick things too.(submitted by Elisabeth from Brazil)One way to outthink others is to make them think you think you're not really thinking what you're trying to get them to think you think.(submitted by Krista Lewis)Whether the weather is cold,Whether the weather is hot,We’ll weather the weather, whatever the weather,Whether we like it or not.(submitted by Jen Kerr from Canada)Three free throws. (Repeat 3x.)Three thieves thank you. (Repeat 3x.)A Tudor who tooted a flutetried to tutor two tooters to toot.Said the two to their tutor,"Is it harder to tootor to tutor two tooters to toot?"Never trouble about trouble until trouble troubles you!If a Hottentot taught a Hottentot totTo talk ere the tot could totter,Ought the Hottenton totBe taught to say aught, or naught,Or what ought to be taught her?If to hoot and to toot a Hottentot totBe taught by her Hottentot tutor,Ought the tutor get hotIf the Hottentot totHoot and toot at her Hottentot tutor?Twelve twins twirled twelve twigs.Tie three tree twigs.(submitted by Lisa MacIntyre)Truly rural.Toy boat, toy boat, toy boat.(submitted by Donna Hoult)You usually use unique unicorns.Betty loves the velvet vest best.(submitted by Ian Wilson)Vincent vowed vengeance very vehemently.Vincent the very vivacious vacuuming vampire visited Victor Von Viking the vegetarian veterinarian vacationing in Valentine Valley.(submitted by Madu Bodinagoda)Which wristwatch is a Swiss wristwatch?Fuzzy Wuzzy was a bear,Fuzzy Wuzzy had no hair,Fuzzy Wuzzy wasn't very fuzzy,Was he?Whether the weather is warm,Whether the weather is hot,We have to put up with the weatherWhether we like it or not.(submitted by Montserrat Casas)Whether the weather is cold,Whether the weather is hot,We’ll weather the weather, whatever the weather,Whether we like it or not.(submitted by Jen Kerr from Canada)Would that we would work without weariness!(adapted from submission by Nguyen Quoc Viet)If two witches were watching two watches: which witch would watch which watch?(anonymous submission)Three Swedish switched witches watch three Swiss Swatch watch switches. Which Swedish switched witch watched which Swiss Swatch watch switch? (submitted by Stela Bortolon)Lesser leather never weathered wetter weather better.Wrist watch, wrist watch, wrist watch.(submitted by Donna Hoult)How much wood would a woodchuck chuck if a woodchuck could chuck wood? (submitted by Susanna Garcia Pons)"Extra, Extra!" Exton exclaimed excitedly.Sixish.Expect exactly, exactly expect excellence.(submitted by Josefine Mangaoang)Exemplary example exempts jinxes.(submitted by Josefine Mangaoang)Exacting vixen exudes existence.(submitted by Josefine Mangaoang)Extreme exercise exacerbates exhaustion.(submitted by Josefine Mangaoang)Yellow yo-yos,Yellow yo-yos,Yellow yo-yos.Yellow Jello. Yellow Jello. Yellow Jello. Yellow Jello.(submitted by Rose Richman)Zebras zig and zebras zag.Zac the xenophobic zebraLived in a XebecAnd zealously zapped out zangy zippy xeroxed tuneson his Zippy xylophone and zingy zither.(submitted by James Corr)To sit in solemn silence in a dull dark dock in a pestilential prison with a life long lock awaiting the sensation of a short sharp shock from a cheap and chippy chopper on a big black block.(From Gilbert and Sullivan's "The Mikado"; thanks to Teresa Howie for identifying the source of this quote.)。
英文的长篇笑话
first driver.
The second replied, "I did, but I had some money left, so we're going to
the cinema now."
(Present continuous / just for fun)
"The Weather forecast?"
"Yes, the weather forecast. the forecaster said on the one hand it might
be fine but on the other hand there might be some rain."
told him he would not take the test.
The student asked, "Do you know who I am?"
The prof said, "No and I don't care."
The student asked again, "Are you sure you don't know who I am?"
(Cantonese students have problems with "on the other hand" because there
is a similar expression in Cantonese that means "in addition". This joke
名人名言
Inspirational QuotesThings turn out best for people who make the best out of the way things turn out.Submitted by: somebody.....2042The greatest pleasure in life is doing what people say you cannot do. Submitted by: me1797Live each day as if it were your last because tomorrow may never come. Submitted by: Alan1434The only difference between try and triumph is a little umph.Submitted by: *Tasha1383You’ve gotta dance like there’s nobody watching,Love like you’ll never be hurt,Sing like there’s nobody listening,And live like it’s heaven on earth.– William W. PurkeySubmitted by: amy1299Never regret anything because at one time it was exactly what you wanted. Submitted by: mimi1213It’s not about how hard you hit.It’s how hard you get hit and keep moving forward.Submitted by: mikeyAdvertisements1021It takes a lot of courage to forgive someone…but it takes an even bigger courage to ask for forgiveness!Submitted by: RominNiamat954You walk through life much easier with a smile on your face.937A winner is a loser who never gave up.Submitted by: chege887When ending a day you should never say “I could have”, “I should have”, or “I would have”. At the end of the day you should always say “I did”.Submitted by: louville784Most of the important things in the world have been accomplished by people who have kept on trying when there seemed to be no hope at all.–Dale CarnegieAdvertisements627Don’t Chase Your Dreams..CATCH THEMSubmitted by: Lola599Life should not be a journey to the grave with the intention of arriving well- preserved, but to skid in sideways, chocolate in one hand, wine in the other, and still screaming, “Whoo! What a ride!”Whenever you feel you will never see light, feel warmth or be happy ever again, just remember, somewhere on earth right now, the sun is rising.Submitted by: ^_^587Today I shall behave as though this day is the one by which I shall may be remembered.Submitted by: dazWhen one door of happiness closes, another opens; but often we look so long at the closed door that we do not see the one which has been opened for us. Submitted by: Nathan528When your mind says give up hope whispers one more try.Submitted by: Meg487Do not go where the path may lead, go instead where there is no path and leave a trail.Submitted by: linnea469Forget yesterday, live for today, tomorrow will take care of it itself.Submitted by: lfc007469Be someone you would be proud to knowSubmitted by: jujubee444Here’s to the crazy ones. The misfits.The rebels.The troublemakers. The round pegs in the square holes. The ones who see things differently. They’re not fond of rules. And they have no respect for the status quo. You can quote them, disagree with them, glorify or vilify them. About the only thing you can’t do is ignore them. Because they change things. They push the human race forward. And while some may see them as the crazy ones, we see genius. Because the people who are crazy enough to think they can change the world, are the ones who do.– Apple Inc.443Never regret a day in your life, “Good day gives you joy while bad day gives you experi ence”. Both are important for a successful life.Submitted by: ABEL, AAdvertisements440Be someone else’s sunshine. Be the reason someone smiles today.435If God gave us all good days, how would we learn from our mistakes? Submitted by: snn404When life rains on your parade- –> bring out the slip’n’slide.Submitted by: me392Sometimes it’s not how good you are, but how bad you want it.Submitted by: Vgirl19384Life may not lead you where you want, but have faith and you are exactly where you were meant to beSubmitted by: Nikki PesterAdvertisements380Life isn’t an adventure that should be taken fast.take it slow live your life, enjoy the days you have because you never know when your days will be numbered.Submitted by: eb.348Nothing lasts forever,So this saddness will pass.Submitted by: *Kea*337Live every day like it’s your last.“Accept that you have lost, but never accept that you have failed”Submitted by: JD315Never give up on something you really want. It’s difficult to wait, but more difficult to regret.315You have to put up with a little rain to get to the pot of gold at the end of the rainbowSubmitted by: kenny313Love others for who and what they are not..do not love them for what they have… ^^Submitted by: Denise Michelle Pasoquen312When you have no one around you, believe that you got yourself and everything is gonna work perfectly.Submitted by: YINKA AJIBODE281The scariest moment is always just before you start.–Stephen King281Dont expect a miracle ; Be the miracle .Submitted by: vckAdvertisements275A ship is safe in harbor, but that’s not what ships are for.– William G.T. SheddSubmitted by: Rachel271Life is full of unexpected things but always remember that it’s hard to beat a person who never gives up.Submitted by: Savanah Crane267The meaning of life is to give life meaning…..Submitted by: PriyaLife is as extreme as you want to make it. (quoted from Sponge Bob, he is wise)Submitted by: Jakob Arana256There will be a moment in your life where you’ll just want to give up but you must push yourself to continue its those moments that make us stronger and make that next moment just a little easier. Never give up on yourself and others will never give up on you.Submitted by: TonyAdvertisements247When someone you love breaks up with you, cry a river, build a bridge and get over it.Submitted by: Carissa241Tell those around you that you love them, you may not get another chance. Submitted by: Ma.Lyzle (lala) Snead239If you think you don’t make a difference in this world, remember one rain drop raises the ocean.Listen up guys.A true love is the person that loves you because you are you, not the guy next to you.So never think that you have to change to find her!!! The woman of your dreams will love you because you are…just that.YOU.Submitted by: Kacey231Expectations may sometimes lead you to disappointments, but the anger of getting disappointment may sometimes lead you to what you expected. Submitted by: JAIMIN231Today is the first day of the rest of your life, make it work for you.Submitted by: zeyzird230Im hurt, and I’m heartbroken, and I’m sad, and I’m depressed, and ive been crying, but I dontwanna let it ruin my life.Stand up for what is right, even if you’re standing alone!!Submitted by: gaby221Be courageous, It’s the only place left uncrowded.Submitted by: Judy216A smile can save a life, it saved mine, my friends, and my whole world. Before you take the last peice offer it to someone else.Submitted by: Love, Love, Ride, SingAdvertisements206Fairy tales are more than true; not because they tell us that dragons exist, but because they tell us that dragons can be beaten.–G.K. Chesterton205Sometimes we need to go through the pain and mistakes to be able to appreciate and understand what we really value and want in our lives. Submitted by: Divine Lapus202You do n’t have to be great to start, but you have to start to be great.–Zig Ziglar201Don’t look for inspiration. Start working and inspiration will come to you. Submitted by: alina195Possible is more a matter of attitude, a matter of decision, to choose among the impossible possibilities, when one sound opportunity becomes a possible solution.–Dejan Stojanovic。
英语双关语笑话23篇 English Puns
英语双关语笑话23篇English PunsThree tomatoes are walking down the street, a poppa tomato, a momma tomato, and a little baby tomato. The baby tomato is lagging behind the poppa and momma tomato. The poppa tomato gets mad, goes over to the momma tomato and stamps on him --(STAMPS on the ground)-- and says:catch up.There once was a very large lady in our town. She wore a dress size 16. I knew her when she was young, but she had a much smaller size.Why do you think she is now wearing a size 16?I guess she just 8 + 8 (ate and ate).Submitted by David TriminghamA man wanting to borrow another man's newspaper asks, "Are you finishe(d)?" The other man replies, "No, I'm Norwegian."Submitted by Aleksander EriksenI was arrested at the airport. Just because I was greeting my cousin Jack!All that I said was "Hi Jack", but very loud.Submitted by Carcelli's familyA woman was driving in her car on a narrow road. She was knitting at the same time, so she was driving very slowly.A man came up from behind and he wanted to pass her. He opened the window and yelled, "Pull over! Pull over!"The lady yelled back, "No, it's a sweater!"Submitted by: Britt Bolving HansenTwo friends meet and one of them says:"I've taught my dog how to speak English!""That's impossible", says the other man."Dogs don't speak!""It's true! I'll show you." He turns to his dog, "How's the situation in England?"The dog answers: "Rough, rough."Submitted by: Alexandra PedroOne day an English grammar teacher was looking ill.A student asked, "What's the matter?""Tense," answered the teacher, describing how he felt.The student paused, then continued, "What was the matter? What has been the matter? What might have been the matter... ?"Submitted by: FredricTeacher:Rumiko, be careful your purse is open. Someone might take your money!Rumiko:Oh, no. I left it open so I can get more money.Teacher:How can you get more money?Rumiko:The weather report said we would have some change in our weather! Submitted by Walter Lowe, aka "Anonymouse"Boyfriend:What is your favorite music group?Girlfriend:I love U2!Boyfriend:I love you too, but what is your favorite music group?Submitted by PhyllisA horse walks into a bar and the bartender says, "So what's with the long face?" Submitted by Joe Cohen Sped TeacherI hear this new cemetry is very popular. People are just dying to get in. Submitted by Glen AshOne day a man went to see the Mozart's tomb.When he got there, the tomb was open and Mozart was sitting there tearing up pieces of paper.The men asked:"What are you doing with all of your great works of music?" Mozart repied, "I'm decomposing!".Submitted by Marcia VillasanaThere is this man who meets a fairy. He is granted three wishes. Having wished for his most urgent needs the man uses his third wish to ask the fairy to return and give him three more wishes.The fairy complies and says: "You can call me whenever you want.""How can I call you. Please tell me your name." the man says."My name is Nuff," says the fairy."Well", says the man "That is an odd name. I have never heard of it before."The fairy replies, "Surely you will have heard of Fairy Nuff." (fair enough)Submitted by: Uli (Paderborn, Germany)[This one works best when spoken aloud.]Once upon a time a mother skunk had two children named "In" and "Out". They were very active children and whenever In was in, Out was out. When Out was in, In was out.One day when Out was in and In was out, the mother skunk said "Out, go out and find In and tell In to come in." Out went out to find In to bring In back in. Within a minute, Out came back in from going out and Out brought In right back in.Amazed, the mother skunk said, "Out, you just went out to find In and brought In right back in! How did you do it?"To this, Out replied "Instinct!" [In stinked]Submitted by Walter LoweWhat's the difference between white socks and red socks?(Students will most likely answer the color)Then you say, "yes, that's one difference but there's another:The White Sox play in Chicago and the Red Sox play in Boston!Submitted by:Rolando SilvaIn London, one man to another:A:"You know, my daughter has married an Irishman"B:"Oh, really?"A:"No, O'Reilly"Submitted by:Scalmo (Italy)A man walks into a bar with a lizard on his shoulder. He walks up to the bar and asks for a pint for himself and a half pint for Tiny, his lizard.The barman looks a little taken aback but serves him and Tiny. Finally, curiosity gets the better of him;Barman: Why do you call him Tiny?Man: Because he's my newt.It pays to be prepared to teach newt, lizard and minute afterwards, but expect a few groans as the penny drops!Submitted by Andy Harvey, Solihull College, UK.A useful one on homophones :Once upon a time, somewhere in Europe, a family with three sons lived on a farm. As the farm was too small to support all of them, and the parents were not yet ready to retire, the sons decided to emigrate to South America, where they bought a ranch and raised beef cattle.Question: So what did they call their ranch?Answer: They called it "Focus", because that's where the sun's rays meet (sons raise meat).Submitted by: Jacky AmarThis is the same joke as above, but an earlier submission and worded differently.Three brothers started a cattle ranch out west. They were very successfull, but could not agree what to call their ranch. They finally agreed to wire their father back east and abide by his decision. He replied at once they should call it "focus". They did so, but now argued endlessly about why he had given them that name. They sent him another wire to ask why that name. He replied, "Simple, because focus is where the sun's rays meet (son's raise meat)."Submitted by Don HolzworthA:How do you like your new job at the cemetery?B:I quit after a week. I found the work too frustrating.A:What happened?B:No matter what I said to the customers, they were always dead right! Submitted by Bob Burgel, VancouverThere were two spies escaping from the enemy over the Alps into neutral Switzerland during the war. As they began to feel safe, one spy starts to tell the other what he found out in enemy territory. The other tells him to speak quietly. "Why?", asks his friend a little perplexed. "There's nobody around for miles. I could scream and not a soul would hear us up here.....!""Ah," replied the other,"haven't you heard? There are mountain ears?" (mountaineers)Submitted by Paddy Greenleaf, teacher IH Viseu, PortugalLynn:Tom's always running into cars in front of him at traffic lights making dents.Max:Is he really? A wreckless type, huh? What does he do for a living? Lynn:He is a dent-ist.(If the student can also speak Japanese, then continue the joke.)Max: I suppose he's had to pay a lot in damages.Lynn: No. He usually says "sorry" and gets away with it.Max: Don't they complain?Lynn: It may be strange, but they don't.Max: What are they afraid of?Lynn: They're afraid of shikaeshi from the dentist!(For those of you who don't speak Japanese, "shikaeshi" means revenge or getting back at someone while "shikaishi," which sounds similar, refers to a dentist.)Submitted by Seiichi Nakada, Pu.D (a doctor of punology)A:Did you hear about the guy with the corduroy pillow?B:No, I didn't.A:Really? It made headlines!Submitted by Dale Ehrlich; Seoul, Korea。
英语被动语态练习题
英语被动语态练习题一、选择题1. The new bridge is being built over the river.A) has been builtB) is being builtC) will be builtD) was built2. Many books were donated to the library last week.A) were donatedB) are donatedC) will be donatedD) have been donated3. The meeting has been postponed until next week.A) postponedB) is postponedC) was postponedD) will be postponed4. The letter was written by Tom.A) was writtenB) is writtenC) has been writtenD) will be written5. The flowers are being watered by the gardener.A) are wateredB) are being wateredC) will be wateredD) were watered6. The problem will be discussed at the next meeting.A) will be discussedB) is discussedC) has been discussedD) was discussed7. The windows were cleaned yesterday.A) were cleanedB) are cleanedC) will be cleanedD) have been cleaned8. The cake was baked for the party.A) was bakedB) is bakedC) has been bakedD) will be baked9. The report must be submitted by tomorrow.A) must be submittedB) must submitC) is submittedD) was submitted10. The house is being painted in blue.A) is paintedB) is being paintedC) will be paintedD) was painted二、填空题11. The car ________ (repair) by a mechanic.12. The painting ________ (hang) in the living room.13. The project ________ (complete) before the deadline.14. The room ________ (clean) every day.15. The book ________ (translate) into several languages.16. The news ________ (broadcast) all over the world.17. The concert ________ (organize) by the local community.18. The experiment ________ (conduct) under strict conditions.19. The letter ________ (send) to the wrong address.20. The food ________ (prepare) for the guests.三、改写句子21. The children have been punished by the teacher. (主动语态) _____________________________________________22. The house is being built by the workers. (主动语态)_____________________________________________23. The books were returned to the library by the students. (主动语态)_____________________________________________24. The flowers are being watered by the gardener. (主动语态) _____________________________________________25. The problem was discussed by the committee. (主动语态)_____________________________________________四、翻译题26. 这座桥正在被建造。
2022年新高考全国Ⅰ卷英语试题及参考答案
2022年普通高等学校招生全国统一考试(新高考全国Ⅰ卷)英语本试卷共10页,满分120分。
考试用时120分钟。
注意事项:1. 答卷前,考生务必用黑色字迹钢笔或签字笔将自己的姓名、考生号、考场号和座位号填写在答题卡上。
用2B铅笔将试卷类型(A)填涂在答题卡相应位置上。
将条形码横贴在答题卡右上角“条形码粘贴处”。
因笔试不考听力,选择题从第二部分的“阅读”开始,试题序号从“21”开始。
2. 作答选择题时,选出每小题答案后,用2B铅笔把答题卡上对应题目选项的答案信息点涂黑;如需改动,用橡皮擦干净后,再选涂其他答案,答案不能答在试卷上。
3. 非选择题必须用黑色字迹钢笔或签字笔作答,答案必须写在答题卡各题目指定区域内相应位置上;如需改动,先划掉原来的答案,然后再写上新的答案;不准使用铅笔和涂改液,不按以上要求作答的答案无效。
4. 考生必须保持答题卡的整洁:考试结束后,将试卷和答题卡一并交回。
第二部分阅读(共两节,满分50分)第一节(共15小题;每小题2.5分,满分37.5分)阅读下列短文,从每题所给的A、B、C、D四个选项中选出最佳选项。
AGrading Policies for Introduction to LiteratureGrading Scale90-100, A; 80-89, B; 70-79, C; 60-69, D; Below 60, E.Essays(60%)Your four major essays will combine to form the main part of the grade for this course: Essay 1 =10%; Essay 2=15%; Essay 3=15%; Essay 4=20%Group Assignments(30%)Students will work in groups to complete four assignments(作业)during the course. All the assignments will be submitted by the assigned date through Blackboard, our online learning and course management system.Daily Work/In-Class Writings and Tests/Group Work/Homework(10%)Class activities will vary from day to day, but students must be ready to complete short in-class writings or tests drawn directly from assigned readings or notes from the previous class' lecture/discussion, so it is important to take careful notes during class. Additionally, from time to time I will assign group work to be completed in class or short assignments to be completed at home, both of which will be graded.Late WorkAn essay not submitted in class on the due date will lose a letter grade for each class period it is late. If it is not turned in by the 4th day after the due date, it will earn a zero. Daily assignments not completed during class will get a zero. Short writings missed as a result of an excused absence will be accepted.21. Where is this text probably taken from?A. A textbook.B. An exam paper.C. A course plan.D. An academic article.22. How many parts is a student's final grade made up of?A. Two.B. Three.C. Four.D. Five.23. What will happen if you submit an essay one week after the due date?A. You will receive a zero.B. You will lose a letter grade.C. You will be given a test.D. You will have to rewrite it.BLike most of us, I try to be mindful of food that goes to waste. The arugula(芝麻菜)was to make a nice green salad, rounding out a roast chicken dinner. But I ended up working late. Then friends called with a dinner invitation. I stuck the chicken in the freezer. But as days passed, the arugula went bad. Even worse, I had unthinkingly bought way too much; I could have made six salads with what I threw out.In a world where nearly 800 million people a year go hungry, "food waste goes against the moral grain," as Elizabeth Royte writes in this month's cover story. It's jaw-dropping how much perfectly good food is thrown away—from “ugly"(but quite eatable)vegetables rejected by grocers to large amounts of uneaten dishes thrown into restaurant garbage cans.Producing food that no one eats wastes the water, fuel, and other resources used to grow it. That makes food waste an environmental problem. In fact, Royte writes, "if food waste were a country, it would be the third largest producer of greenhouse gases in the world."If that's hard to understand, let's keep it as simple as the arugula at the back of my refrigerator. Mike Curtin sees my arugula story all the time —but for him, it's more like 12 bones of donated strawberries nearing their last days. Curtin is CEO of DC Central Kitchen in Washington, D.C., which recovers food and turns it into healthy meals. Last year it recovered more than 807,500 pounds of food by taking donations and collecting blemished(有瑕疵的)produce that otherwise would have rotted in fields. And the strawberries? V olunteers will wash, cut, and freeze or dry them for use in meals down the road.Such methods seem obvious, yet so often we just don't think. "Everyone can play a part in reducing waste, whether by not purchasing more food than necessary in your weekly shopping or by asking restaurants to not include the side dish you won't eat," Curtin says.24. What does the author want to show by telling the arugula story?A. We pay little attention to food waste.B. We waste food unintentionally at times.C. We waste more vegetables than meat.D. We have good reasons for wasting food.25. What is a consequence of food waste according to the test?A. Moral decline.B. Environmental harm.C. Energy shortage.D. Worldwide starvation.26. What does Curtin's company do?A. It produces kitchen equipment.B. It turns rotten arugula into clean fuel.C. It helps local farmers grow fruitsD. It makes meals out of unwanted food.27. What does Curtin suggest people do?A. Buy only what is needed.B. Reduce food consumption.C. Go shopping once a week.D. Eat in restaurants less often.CThe elderly residents(居民)in care homes in London are being given hens to look after to stop them feeling lonely.The project was dreamed up by a local charity(慈善组织)to reduce loneliness and improve elderly people's wellbeing, It is also being used to help patients suffering dementia, a serious illness of the mind. Staff in care homes have reported a reduction in the use of medicine where hens are inuse.Among those taking part in the project is 80-year-old Ruth Xavier. She said: “I used to keep hens when I was younger and had to prepare their breakfast each morning before I went to school."I like the project a lot. I am down there in my wheelchair in the morning letting the hens out and down there again at night to see they've gone to bed."It's good to have a different focus. People have been bringing their children in to see the hens and residents come and sit outside to watch them. I'm enjoying the creative activities, and it feels great to have done something useful."There are now 700 elderly people looking after hens in 20 care homes in the North East, and the charity has been given financial support to roll it out countrywide.Wendy Wilson, extra care manager at 60 Penfold Street, one of the first to embark on the project, said: "Residents really welcome the idea of the project and the creative sessions. We are looking forward to the benefits and fun the project can bring to people here."Lynn Lewis, director of Notting Hill Pathways, said: "We are happy to be taking part in the project. It will really help connect our residents through a shared interest and creative activities."28. What is the purpose of the project?A. To ensure harmony in care homes.B. To provide part-time jobs for the aged.C. To raise money for medical research.D. To promote the elderly people's welfare.29. How has the project affected Ruth Xavier?A. She has learned new life skills.B. She has gained a sense of achievement.C. She has recovered her memory.D. She has developed a strong personality.30. What do the underlined words "embark on" mean in paragraph 7?A. Improve.B. Oppose.C. Begin.D. Evaluate.31. What can we learn about the project from the last two paragraphs?A. It is well received.B. It needs to be more creative.C. It is highly profitable.D. It takes ages to see the results.DHuman speech contains more than 2,000 different sounds, from the common "m" and "a" to the rare clicks of some southern African languages. But why are certain sounds more common than others? A ground-breaking, five-year study shows that diet-related changes in human bite led to new speech sounds that are now found in half the world's languages.More than 30 years ago, the scholar Charles Hockett noted that speech sounds called labiodentals, such as "f" and "v", were more common in the languages of societies that ate softer foods. Now a team of researchers led by Damián Blasi at the University of Zurich, Switzerland, has found how and why this trend arose.They discovered that the upper and lower front teeth of ancient human adults were aligned(对齐), making it hard to produce labiodentals, which are formed by touching the lower lip to the upper teeth. Later, our jaws changed to an overbite structure(结构), making it easier to produce such sounds.The team showed that this change in bite was connected with the development of agriculture in the Neolithic period. Food became easier to chew at this point. The jawbone didn't have to do as much work and so didn't grow to be so large.Analyses of a language database also confirmed that there was a global change in the sound of world languages after the Neolithic age, with the use of "f" and "v" increasing remarkably during the last few thousand years. These sounds are still not found in the languages of many hunter-gatherer people today.This research overturns the popular view that all human speech sounds were present whenhuman beings evolved around 300,000 years ago. "The set of speech sounds we use has not necessarily remained stable since the appearance of human beings, but rather the huge variety of speech sounds that we find today is the product of a complex interplay of things like biological change and cultural evolution," said Steven Moran, a member of the research team.32. Which aspect of the human speech sound does Damián Blasi's research focus on?A. Its variety.B. Its distribution.C. Its quantity.D. Its development.33. Why was it difficult for ancient human adults to produce labiodentals?A. They had fewer upper teeth than lower teeth.B. They could not open and close their lips easily.C. Their jaws were not conveniently structured.D. Their lower front teeth were not large enough.34. What is paragraph 5 mainly about?A. Supporting evidence for the research results.B. Potential application of the research findings.C. A further explanation of the research methods.D. A reasonable doubt about the research process.35. What does Steven Moran say about the set of human speech sounds?A. It is key to effective communication.B. It contributes much to cultural diversity.C. It is a complex and dynamic system.D. It drives the evolution of human beings.第二节(共5小题;每小题2.5分,满分12.5分)阅读下面短文,从短文后的选项中选出可以填入空白处的最佳选项。
举证通知书英文
篇一:举证通知书中英文对照
举证通知书
noticetoProduceEvidence
根据《中华人民共和国民事诉讼法》和最高人民法院《关于民事诉讼证据的若干规定》,现将有关举证事项通知如下:
accordingtothecivilProceduralLawofthePeople’sRepublicofchinaandtheSeveralProvisionsoftheSupremePeople’scourtonEvidencesforcivilactions,themattersofproducingevidenceswillnotifyasfollowing:
六、你方收到本通知后,可以与对方当事人协商确定举证期限后,向本院申请认可。你方与对方当事人未能协商一致,或者未申请本院认可,或本院不予认可的,你方应当于年月日前向本院提交证据。若举证期限不足15日,则自收到通知之日起第15日为举证期限届满之曰。逾期不提交证据的,视为放弃举证权利。逾期提交的证据材料,本院审理时不组织质证,裁判时不予采纳。
五、申请证据保全,应当在举证期限届满的七日前提出,本院可根据情况要求你方提供相应的担保。如本案适用简易程序审理,申请证据保全的时间可以不受七日的限制。
Vwhereyouintendtoapplyforpreservationofevidence,youshallfile
anapplicationwiththiscourtseven(7)daysbeforeexpirationoftheevidenceproducingterm.Thiscourtmayrequireyoutoprovidecorrespondingpreservationasthecircumstancesmayrequire.Providedthatthesummaryprocedureisfollowedinthiscase,thetimeforpreservationofevidenceisnotlimitedby10days.
英语课堂小笑话集
英语课堂小笑话集(总16页)--本页仅作为文档封面,使用时请直接删除即可----内页可以根据需求调整合适字体及大小--英语课堂小笑话英语笑话(一)Q: Which is the strongest creature in the worldA: The snail. It carries its house on its back.因为snail(蜗牛)的后背上总是背着一所房子,所以说蜗牛是世界上最强壮的生物是不足为奇的。
你说呢Q: What do people do in a clock factoryA: They make faces all day.一看到make faces这个短语,你可千万别以为是在钟表厂工作的人整天都做鬼脸呀!因为除了这个意思以外,它还可以从字面上解释为制造钟面。
Q: How do you stop a sleepwalker from walking in his sleepA: Keep him awake.怎样才能不让梦游者(sleepwalker)梦游(walk in his sleep)呢最简单的方法就是不让他睡觉。
虽然这不是治疗方法,但如果让梦游者醒着呢,他的确就不会去梦游了。
英语笑话(二)He is really somebody-- My uncle has 1000 men under him.-- He is really somebody. What does he do-- A maintenance man in a cemetery.他真是一个大人物-- 我叔叔下面有1000个人。
-- 他真是一个大人物。
干什么的-- 墓地守墓人。
英语笑话(三)Not long after an old Chinese woman came back to China from her visit to her daughter in the States, she went to a city bank to deposit the US dollars her daughter gave her. At the bank counter, the clerk checked each note carefully to see if the money was real. It made the old lady out of patience.At last she could not hold any more, uttering. "Trust me, Sir, and trust the money. They are real US dollars. They are directly from America."它们是从美国直接带来的一位中国老妇人在美国看望女儿回来不久,到一家市银行存女儿送给她的美元。
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Leading Indicators of Safety In Virtual OrganizationsSubmitted to:Stig JohnsenSINTEF Industrial ManagementSP Andersens veg 5NO-7465Trondheim, Norway47.957.27788 voiceEmail: Stig.O.Johnsen@sintef.noSubmitted by:Martha GrabowskiLeMoyne CollegeProfessor, DirectorInformation Systems Program1419 Salt Springs RoadSyracuse, New York 13214315.445.4427 voice 4540 faxResearch ProfessorDepartment of Decision Sciences & Engineering SystemsRensselaer Polytechnic Institute110 8th Street CII 5015Troy, New York 12180-3590518.276.2954 voice 8227 faxemail: grabowsk@/~grabowsk13 January 2006Under review at Safety Science, January 2006Leading Indicators of SafetyIn Virtual Organizations1.IntroductionA primary purpose in measuring safety is to develop intervention strategies to avoid future accidents. Recognizing signals before an accident occurs offers the potential for improving safety, and many organizations have sought to develop programs to identify and benefit from alerts, signals and prior indicators. A recent study by the U.S. National Academy of Sciences focused on these signals, the conditions, events and sequences that precede and lead up to accidents, or the “building blocks” of accidents (Phimister, Bier, & Kunreuther, 2003, p.6):In the aftermath of catastrophes, it is common to find prior indicators, missed signals, and dismissed alerts, that, had they been recognized and appropriately managed before the event, might have averted the undesired event. Indeed, the accident literature is replete with examples, including the space shuttle Columbia (Columbia Accident Investigation Board, 2003), the space shuttle Challenger (Vaughan, 1996),Three Mile Island (Chiles, 2002), the Concorde crash (BEA, 2004), the London Paddington train crash (Cullen, 2000) and American Airlines flight 587 to Santo Domingo (USA Today, May 25, 2003), among many others (Kletz, 1994; Marcus & Nichols, 1999; Turner & Pidgeon, 1997).In this paper, we address the challenge of identifying and evaluating leading indicators of safety in virtual organizations--organizations comprised of multiple, distributed members, temporarily linked together for competitive advantage, that share common value chains and business processes supported by distributed information technology (Davidow and Malone, 1992; Mowshowitz, 1997; Kock, 2000). Examples of virtual organizations in which risk mitigation processes are critical include healthmaintenance systems of doctors in widely dispersed managed care environments, medical societies, and electronically-linked members of Physicians On-Line (Physicians On-Line/Medscape, 2006); fire and emergency medical services units providing support in large-scale disasters (Weick, 1993; 1996); oil spill response teams responding to oil spills of national significance (Harrald, Cohn, & Wallace, 1992; Grabowski, Harrald & Roberts, 1997); aerospace conglomerates jointly developing mission- and safety-critical applications (Augustine, 1997; Spotts & Castellano, 1997); international oil exploration consortia merging in the North Sea (Herring, 2002) and developing oil fields in the Caspian Sea (Oil and Gas Investor, 2003), global telecommunications alliances providing 99% of the world's inter-bank financial transactions (SWIFT, 2006), offshore oil and gas exploration and drilling in Norway (Gulbrandsoy, Hepso & Skavhaug, 2002), and Danish offshore wind farm management consortia (Andersen & Drejer, 2005).Risk in systems can exist because one or more components in the system are risky, or it can result from components that are themselves relatively safe, but interact in ways that increase risk. Perrow (1984) discusses such risk propensities at length, but generally for smaller systems than those that can be imagined as virtual organizations. Here we use the commonly used engineering definition of a risky event as one that is low probability but high consequence (e.g. Wenk, 1982).Virtual organizations and systems of organizations are of increasing interest to systems and organizational researchers. The literature on inter-organizational alliances offers one paradigm for studying organizational systems (Barrett & Konsynski, 1982; Cash & Konsynski, 1985; Johnston & Vitale, 1988; Hagedoorn, 1993; Benasou &Venkatraman, 1995), as does the literature on network organizations (Powell, 1990; Miles & Snow, 1992; Nohria & Eccles, 1992). More recently, researchers have begun to examine systems of organizations (e.g. Uzzi, 1997; Eisenhardt & Schoonhaven, 1996), and risk propensities in large-scale systems have received empirical attention (Perrow, 1984; Pauchant & Mitroff, 1992; Sagan, 1993; Vaughan, 1996; Grabowski & Roberts, 1996; 1997; 1999). The efficiency, effectiveness and trustworthiness of virtual organizations has also been the subject of recent research (Staples, Hulland and Higgins, 1999; Kasper-Fuehrer & Ashkanasy, 2001; Morris, Marshall & Rainer, 2002).In this paper, we draw on research on high reliability organization (HRO's) (LaPorte, 1982; Roberts, 1990); risk, safety and leading indicator research (Shrivastava, 1986; Wildavsky, 1988; Sagan, 1993; Vaughan, 1996, Mearns, Whitaker & Flin, 2001, 2003; Phimister, Bier & Kunreuther, 2003); research on network organizations (Powell, 1990; Nohria & Eccles, 1992; Jarillo, 1988; Thorelli, 1986) and inter-organizational systems (Barrett & Konsynski, 1982; Johnston & Vitale, 1988; Konsynski & McFarlan, 1990); and virtual organization research (Davidow and Malone, 1992; Goldman, Nagel & Preiss, 1995; Preiss, Goldman and Nagel, 1996; Staples, Hulland & Higgins, 1999; Kock, 2000; Morris, Marshall & Rainer, 2003) in our exploration of leading indicators of safety in virtual organizations. We begin by discussing risk propensity in virtual organizations, and examine in detail characteristics of virtual organizations important to enhancing safety. We then discuss research to identify leading indicators of safety in virtual organizations, and conclude with a discussion of next steps and suggestions for how thoughtful management of leading indicators can enhance safety.2. Risk Propensity in Virtual OrganizationsThe major distinction between virtual and other organizations is that the former are networked (usually electronically) organizations that transcend conventional organizational boundaries (e.g. Barner, 1996; Berger, 1996; Mowshowitz, 1997). The bonds among members of virtual organizations are temporary, and virtual organizations are noted for forming and dissolving relationships with other members of the virtual organization (e.g. Palmer, Friedland & Singh, 1986; Bleeker, 1994; Nohria & Berkley, 1994; Coyle & Schnarr, 1995). The traditional advantages attributed to virtual organizations include adaptability, flexibility, and the ability to respond quickly to market changes.Although members of virtual organizations may occasionally meet face-to-face as well as electronically, members are not co-located, and virtual organization success hinges on shared, interdependent business processes that are designed to achieve shared business objectives. Virtuality thus has two features: the creation of a common value chain among the distinct entities of the virtual organization (Benjamin & Wigand, 1995; Rayport & Sviokla, 1995), and business processes supported by distributed information technology (Palmer & Speier, 1997; Kumar, 2001). Virtual organizations are distinguished from traditional network organizations by the temporary linkages that tie together the distinct organizations, and by the members' shared business processes and common value chains supported by distributed information technology. Network organizations, in contrast, generally establish more permanent linkages between members, and generally do not create shared value chains and interdependent business processes between members, as virtual organizations do.Research shows that risk propensity in traditional organizations has its roots in a number of factors (Wenk, 1982; Perrow, 1984, National Research Council, 1996; Grabowski & Roberts, 1996; Tenner, 1996; Vaughan, 1996). One cause of risk is that the activities performed in the system are inherently risky (e.g. mining, medicine, manufacturing, airline transportation); another is that the technology is inherently risky, or exacerbates risks in the system (e.g. drilling equipment, high speed engines, nuclear propulsion systems). Yet a third cause is that the individuals and organizations executing tasks, using technology, or coordinating both can propagate human and organizational errors. In addition, organizational structures may encourage risky practices or encourage workers to pursue risky courses of action (e.g. lack of formal safety reporting systems or departments in organizations, or organizational standards that are impossible to meet without some amount of risk taking). Finally, organizational cultures may support risk taking, or fail to sufficiently encourage risk aversion (e.g. cultures that nurture the development of "cowboys" who succeed by taking risks, or of management practices that encourage new generations of risk takers) (Grabowski & Roberts, 1996).Virtual organizations are characterized by several of the same factors that determine a traditional organization's risk propensity. Tasks executed by members of the virtual organization, although distributed, may still be inherently risky (e.g. oil exploration, fire fighting, eye surgery), as in traditional organizations. Technology used to execute the virtual organization’s tasks may also be inherently risky (e.g. drilling equipment, interacting chemicals, lasers, or infrared equipment). Human and organizational error can continue to propagate in virtual organizations as long as humans and organizations are a part of them. Organizational structures in virtual organizationsmay make risk mitigation difficult (e.g. virtual management structures can reduce physical oversight and contact, and organizational relationships presumably based on shared commitments to safety may not be equally shared among members of a virtual organization). Finally, organizational cultures may send confusing or contradictory messages to members about risk tolerance in the virtual organization (e.g. safety bulletins that celebrate the number of accident free days while the virtual organization simultaneously rewards workers for flaunting safety practices and "living on the edge").However, risk propensity in virtual organizations has some interesting differences. Because virtual organizations are distributed, networked organizations with fluid and shared business processes, risk in the virtual organization can migrate between organizational members, making risk identification and mitigation difficult. Because virtual organizations are comprised of members with their own individual goals, policies, and cultures, and because the members are bound in temporary alliances that reflect changing marketplace opportunities, developing a shared culture of reliability and shared commitments to reliability goals is difficult, as the presence of simultaneous interdependence and autonomy creates an inherent tension in the virtual organization. Finally, because virtual organizations are large scale organizations with complex interactions between their members, precipitating incidents and accidents may have long incubation periods, making identification of a leading error chain difficult (Grabowski & Roberts, 1997; 1999). These risk propensities can provide important clues about effective risk mitigation in virtual organizations, and important motivation for examining leading indicators of safety in virtual organizations.3.Leading IndicatorsSafety performance has traditionally been measured by ‘after the loss’ type of measurements such as accident and injury rates, incidents and dollar costs. However, there is a growing consensus among safety professionals and researchers that lagging indicators, which means that an accident must occur or a person must get injured before a measure can be made, may or may not provide the necessary insights for avoiding future accidents. A low reported accident rate, even over a period of years, is no guarantee that risks are being effectively controlled, nor will it ensure the absence of injuries or accidents in the future (Lindsay, 1992).Leading indicators, one type of accident precursor, are conditions, events or measures that precede an undesirable event and that have some value in predicting the arrival of the event, whether it is an accident, incident, near miss, or undesirable safety state. Leading indicators are associated with proactive activities that identify hazards and assess, eliminate, minimize and control risk (Construction Owners Association of Alberta, 2004). Lagging indicators, in contrast, are measures of a system that are taken after events, which measure outcomes and occurrences.Examples of leading indicators include near hit reporting in anesthesia management (Pate-Cornell, 2003), accident precursor assessment programs in nuclear safety (Sattison, 2003), and hazard identification and analyses for offshore oil and gas in the United Kingdom (Step Change in Safety, 2004). Examples of lagging indicators include recordable injury frequencies, lost time frequencies, total injury frequencies, lost timeseverity, vehicle accident frequencies, workers’ compensation losses, property damage costs, and numbers and frequency of accident investigations (Construction Owners Association of Alberta, 2004).Leading and lagging indicators differ by granularity and focus, as seen in Figure 1 (Bergh, 2003). Leading indicators are primarily focused at the individual and perhaps departmental level. In contrast, lagging indicators are broader in scope and generally focus on organizational measures. Lagging indicators are seldom focused on individual performance; similarly, leading indicators are most often focused on small units of analysis (i.e., at the individual, group or departmental level). These differences have important implications for data collection, analysis and measurement of leading indicators.Figure 1Units of Analysis for Leading and Lagging Indicators (Bergh, 2003)Figure 1 also suggests the notion of shared leading and lagging indicators within the same organization or domain, ideas echoed by Bergh (2003), Petersen (1998), and Step Change in Safety (2004). Thus, both leading and lagging indicators coexist within the same domain, although they can be expected to focus on different units of analysis within that domain.Indicator CharacteristicsThe links or associations between signals or indicators in a system and the onset of adverse events may take a variety of forms. Some indicators may precisely herald the onset of an adverse event in a predictive way; other indicators may be direct causes of adverse events. In either of these cases, the links or associations between indicators and events are direct, visible and demonstrable. An individual’s presence could be an indicator, for instance; one such example of a causal link between an indicator and an adverse event is the recent case where a nursing home attendant was convicted of administering lethal doses of medications to patients in the home. The signal and cause were the presence of the attendant; the adverse event was clearly the death of the nursing home residents.Historical accident analyses, however, reveal that accident causes are more often the result of interactions between interdependent elements in complex, high hazard systems (Perrow, 1984). Investigations into the dynamics of system interdependence and complexity are still the focus of much on-going research (Sagan, 2004). Thus, several indicators or signals can be correlated with the onset of an adverse event. Thesecorrelations might be links between single indicators and adverse events, or between groups or clusters of indicators and adverse events. Examples of correlations between leading indicators and adverse events include links between electrical system defects and main propulsion system failures. Examples of correlations between groups of leading indicators can be seen in links between large numbers of port state detentions, structural failures and substance abuse problems within a shipping company and an operational failure (Soma, 2005). Some indicators may serve as proxies or surrogates for other indicators. Proxy or surrogate indicators are substitutes or approximations for leading indicators; they are more easily measured, captured or analyzed than are the true leading indicators, and they have predictive associations with adverse events. Clusters and groups of indicators have also been used to develop risk indices to categorize and rank leading indicators of risk in a system. Each of these different types of relationships between indicators and adverse events can be considered in analyses of leading indicators for virtual organizations.Previous Work with Leading IndicatorsLeading indicators have been studied in many types of systems, with widely varying results (Leveson, 1995; Hollnagel, 1998). Many economic systems, including the U.S. economy, use composite indexes and economic series with leading, coincident, and lagging indicators of economic performance (Conference Board, 1997; 2004). In economic systems, leading indicators are those indicators that tend to shift direction in advance of a business cycle. Coincident economic indicators, such as employment and production, are broad series that measure aggregate economic activity, and thus define the business cycle. Lagging indicators tend to change direction after the coincident series.In economic systems, lagging indicators are used to confirm turning points and to warn of structural imbalances in the economy.Over the past thirty years, the medical community has developed increasingly sophisticated leading indicators of health in the United States. Initially, these efforts focused on identifying predictors of individual mortality; recently, the focus has shifted to include identifying leading indicators for improving the nation’s health (Chrvala & Bulger, 1999), echoing the notion from the previous section that leading indicators can be individually and broadly focused within the same domain. The electric power industry has also evaluated the predictive validity of leading indicators of individual and group safety and performance in nuclear power plants (Gross, Ayres, Wreathall, Merritt, & Moloi, 2001; Ayres & Gross, 2002).Some industries, such as aviation, have a relatively long history of seeking to identify leading indicators; others, such as blood banks and hospitals, are relative newcomers to the field. Nevertheless, each field uses similar information-gathering processes and weighs common design choices (Tamuz, 2003). Some of these industries discovered accident precursors based on their common experiences, such as having to draw on small samples of accidents (March, Sproull & Tamuz, 1991), while other industries developed signal detection programs as a result of learning by imitation (Levitt & March, 1988), such as medicine’s Patient Safety Reporting System, which drew on aviation’s experience with its Aviation Safety Reporting System (Tamuz, 2003). It is worthwhile noting that, although very little predictive validity has been provided with theuse of leading indicators, attempts still continue to identify and validate such measures in a variety of safety- and mission-critical industries. One such example is given in the following section, where a pilot study to identify a framework for leading indicators in marine transportation is described.4.Pilot Study:Leading Indicators for Marine TransportationA pilot study was undertaken in 2004 to identify, evaluate and analyze a set of leading indicators of safety for marine transportation. Initially, the focus of the project was on domestic U.S. tanker operations. It was thought that such a pilot study could serve as the foundation for a broader study of leading indicators in virtual organizations, such as international shipping organizations, as well as remote offshore oil and gas operations.Previous work in leading indicators suggests that the process of identifying leading indicators involves two steps: first, identifying significant safety factors, and second, identifying suitable metrics or leading indicators that correlate with the safety factors (Khatib-Rahbar, Sewell, & Erikson, 2000; Sorensen, 2002). In this pilot study, an expert elicitation technique, referred to as Value Focused Thinking, was utilized in order to identify significant safety factors in marine transportation. The initial safety factor structure elicited is shown in Figure 2 (Merrick, Grabowski, Ayyalasomayajula & Harrald, 2005).Figure 2 illustrates each of the safety factors thought important by key decision makers in the pilot study’s industry partner organization. The senior management teamidentified that hiring quality personnel, providing safety orientation, promoting safety through top management commitment, and developing a formal learning system were critical to improving an organization’s safety culture. The vessel management team identified that responsibility, communication, problem identification, problem prioritization and a feedback system aboard the vessel were critical to improving a vessel’s safety culture. Similarly, the safety, health and environmental team identified that individual empowerment, responsibility, and systems for anonymous reporting and feedback were essential to improving an individual’s safety attitude. The items elicited in the expert elicitation sessions thus represent the initial safety factor structure.Figure 2. Initial safety factor structureFigure 3 shows the research model constructed from the Figure 2 safety factors (Merrick, et al., 2005). The independent variables in the boxes to the left were derived from the expert elicitation sessions; the dependent variables listed under “Safety Performance” in the boxes on the right hand side of Figure 3 represent measures of safety performance commonly used in marine transportation (Mearns, et al., 2001; 2003; Soma,2005). Each arrow in Figure 3 represents a causal relationship. For example, an improvement in organizational safety is hypothesized to lead to an improvement in vessel safety culture and an improvement in individual safety attitudes.Figure 3. Research Model for Safety Factors for Marine Transportation *H1 through H13 refer to hypotheses in the research model (Table 1)The research model hypothesized that improvements in safety performance can be linked causally to the organizational, vessel and individual safety factors. The organizational safety factors--Hiring Quality Personnel, Safety Orientation, Promotion of Safety and Formal Learning System—were proposed to influence the safety performanceof organizations. Similarly, the vessel safety factors and individual safety attitudes were hypothesized to influence the safety performance of vessels and individuals, respectively. The hypotheses associated with the research model are listed in Table 1.Organizational HypothesesH1 Hiring Quality People at the organizational level will lead to an improvement in safety performanceH2 Safety Orientation at the organizational level will lead to an improvement in safety performanceH3 An effective formal learning system at the organizational level will lead to an improvement in safety performanceH4 Promotion of safety at organizational level will result in better safety performanceShipboard HypothesesH5 Prioritization of Safety at the shipboard level will result in better safety performanceH6 Effective Communication at shipboard level will result in better safety performanceH7 Effective problem identification at the shipboard level will result in better safety performanceH8 Effective feedback at the shipboard level will result in better safety performanceH9 Responsibility at shipboard level will result in better safety performanceIndividual HypothesesH10 Employee empowerment will result in better safety performanceH11 Anonymous Reporting by individuals will result in better safety performance.H12 Effective feedback at individual level will result in better safety performanceH13 Responsibility at the individual level will result in better safety performance.Table 1: List of Organizational, Shipboard and Individual HypothesesBoth objective measures of safety and subjective safety climate measures were used to establish the statistical significance of the safety factors and identify the leading indicators. The correlations between the significant safety factors and safety performance were used to validate the leading indicators. In the past, guidance notes have been developed by research organizations that suggest the use of objective measures asleading indicators (Chrvala & Bulger, 1999; Step Change in Safety, 2004). However, the validity of these indicators has not been empirically established. Thus, one of the contributions of this pilot study was to empirically assess objective safety and subjective safety climate data to identify leading indicators of safety that are quantitatively validated and supported by the available data.5. Leading Indicators in Virtual OrganizationsThe initial pilot study provided a research model and framework from which to consider the development of leading indicators of safety in virtual organizations. High reliability organization (HRO) research also suggests issues that merit attention in developing leading indicators for virtual organizations. In high reliability organizations, as in safety-critical virtual organizations, small errors can propagate into grave consequences, and risk mitigation processes are critical to the organization's survival (Roberts, 1990; LaPorte and Consolini, 1991; Sagan, 1993; Weick, 1987; 1993). Typical examples of high reliability organizations include flight operations aboard aircraft carriers, command and control organizations in battle management operations, the U.S. air traffic control system, and operations of some U.S. commercial nuclear power plants (Rochlin, LaPorte, & Roberts, 1987; LaPorte, 1988; Roberts, 1990; La Porte & Consolini, 1991).Initially, four findings from high reliability research seem appropriate to consider in our examination of leading indicators of safety in virtual organizations (Grabowski & Roberts, 1999). First, high reliability organizations are characterized by prioritization ofsafety and reliability as goals, as such practices enhance a milieu of safe operations. High reliability organizations clearly define what they mean by safety goals and establish safety standards against which they assess themselves. For instance, at the Navy Aviation School in Monterey, California, aviation accidents are detailed on a large board adjacent to a chart showing the Navy's aviation safety record since the early 1950's. In safety-critical virtual organizations, prioritizing safety and reliability across the entire virtual organization is also important. Thus, prioritizing safety across the virtual organization is one example of a safety factor for improving safety in a virtual organization.Operationalizing safety and reliability goals in high reliability organizations often takes the form of redundancy in personnel and technology. Pilots and co-pilots on commercial airliners can both fly the airplane, and both pilots and co-pilots are required aboard before commercial airliners will fly. In safety-critical virtual organizations, redundancy creates opportunities for system members to communicate, to cross check information, and to ensure that individual and business goals and plans are consistent with the goals and plans of the virtual organization, particularly in a dynamic environment. The geographical distribution of virtual organizations and the necessity for reliability enhancing organizations to prioritize safety goals and engage in redundancy suggest the necessity of paying attention to organizational structuring and design in the interests of safety in virtual organizations.High reliability organizations are also noted for developing a high reliability culture that is decentralized and constantly reinforced, often by continuing practice and through training. For instance, nuclear power plants that run well build in high reliability。