Chapter-1
1-what is energy
Chapter 1: What is Energy?Energy causes things to happen around us.Look out the window. During the day, thesun gives out light and heat energy. Atnight, street lamps use electrical energy tolight our way.When a car drives by, it is being poweredby gasoline, a type of stored energy.The food we eat contains energy. We use that energy to work and play.We learned the definition of energy in the introduction:Energy Is the Ability to Do Work.Energy can be found in a number of different forms. It can be chemical energy, electrical energy, heat (thermal energy), light (radiant energy), mechanical energy, and nuclear energy.Stored and Moving EnergyEnergy makes everything happen and can be divided into two types:•Stored energy is called potential energy.•Moving energy is called kinetic energy.With a pencil, try this example to know the two types of energy.Put the pencil at the edge of the desk and push it off to the floor. The moving pencil uses kinetic energy.Now, pick up the pencil and put it back on the desk. You used your own energy to lift and move the pencil. Moving it higher than the floor adds energy to it. As it rests on the desk, the pencil has potential energy. The higher it is, the further it could fall. That means the pencil has more potential energy.How Do We Measure Energy?Energy is measured in many ways.One of the basic measuring blocks is called a Btu. This stands for British thermal unit and was invented by, of course, the English.Btu is the amount of heat energy it takes to raise the temperature of one pound of water by one degree Fahrenheit, at sea level.One Btu equals about one blue-tip kitchen match.One thousand Btus roughly equals: One average candy bar or 4/5 of a peanut butter and jelly sandwich.It takes about 2,000 Btus to make a pot of coffee.Energy also can be measured in joules. Joules sounds exactly like the word jewels, as in diamonds and emeralds. A thousand joules is equal to a British thermal unit.1,000 joules = 1 BtuSo, it would take 2 million joules to make a pot of coffee.The term "joule" is named after an English scientist JamesPrescott Joule who lived from 1818 to 1889. He discovered thatheat is a type of energy.One joule is the amount of energy needed to lift somethingweighing one pound to a height of nine inches. So, if you lifted afive-pound sack of sugar from the floor to the top of a counter(27 inches), you would use about 15 joules of energy.Around the world, scientists measure energy in joules ratherthan Btus. It's much like people around the world using themetric system of meters and kilograms, instead of the Englishsystem of feet and pounds.Like in the metric system, you can have kilojoules -- "kilo" means 1,000.1,000 joules = 1 kilojoule = 1 BtuA piece of buttered toast contains about 315 kilojoules (315,000 joules) of energy. With that energy you could:•Jog for 6 minutes•Bicycle for 10 minutes•Walk briskly for 15 minutes•Sleep for 1-1/2 hours•Run a car for 7 seconds at 80 kilometers per hour (about 50 miles per hour) •Light a 60-watt light bulb for 1-1/2 hours•Or lift that sack of sugar from the floor to the counter 21,000 times! Changing Energyof energy. But it cannot be created AND itcannot be destroyed. Energy has alwaysexisted in one form or another.Here are some changes in energy from oneform to another.Stored energy in a flashlight's batteriesbecomes light energy when the flashlight isturned on.Food is stored energy. It is stored as achemical with potential energy. When yourbody uses that stored energy to do work, itbecomes kinetic energy.If you overeat, the energy in food is not"burned" but is stored as potential energy infat cells.When you talk on the phone, your voice istransformed into electrical energy, whichthe air). The phone on the other endchanges the electrical energy into soundenergy through the speaker.A car uses stored chemical energy ingasoline to move. The engine changes thechemical energy into heat and kineticenergy to power the car.you'll see the glowing wires.)A television changes electrical energy into light and sound energy.Heat EnergyHeat is a form of energy. We use it fora lot of things, like warming ourhomes and cooking our food.Heat energy moves in three ways:1. Conduction2. Convection3. RadiationConduction occurs when energy is passed directly from one item to another. If you stirred a pan of soup on the stove with a metal spoon, the spoon will heat up. The heat is being conducted from the hot area of the soup to the colder area of spoon.Metals are excellent conductors of heat energy. Wood or plastics are not. These "bad" conductors are called insulators. That's why a pan is usually made of metal while the handle is made of a strong plastic.Convection is the movement of gases or liquids from a cooler spot to a warmer spot. If a soup pan is made of glass, we could see the movement of convection currents in the pan. The warmer soup moves up from the heated area at the bottom of the pan to the top where it is cooler. The cooler soup then moves to take the warmer soup's place. The movement is in a circular pattern within the pan (see picture above).The wind we feel outside is often the result of convection currents. You can understand this by the winds you feel near an ocean. Warm air is lighter than cold air and so it rises. During the daytime, cool air over water moves to replace the air rising up as the land warms the air over it. During the nighttime, the directions change -- the surface of the water is sometimes warmer and the land is cooler.Radiation is the final form of movement of heat energy. The sun's light and heat cannot reach us by conduction or convection because space is almost completely empty. There is nothing to transfer the energy from the sun to the earth.The sun's rays travel in straight lines called heat rays. When it moves that way, it is called radiation.When sunlight hits the earth, its radiation is absorbed or reflected. Darker surfaces absorb more of the radiation and lighter surfaces reflect the radiation. So you would be cooler if you wear light or white clothes in the summer.。
牛津英语八年级上册知识点总结
Chapter 1 Water1.we can’t live without (没有) /with（有）waterHe went away without saying goodbye.2.two litres of water （两升水）/ three cups of coffeefour pieces of paper…3. a little oil （有一点）/ little oil（几乎没有）+ 不可数名词a few books/ few books + 可数名词4.too much + 不可数名词（太多）/ much too （太）+形容词too many + 可数名词（太多）5.boiling water （正在沸腾的水）& boiled water （开水）relaxing （令人放松的）& relaxed（人）感到放松的6.cover A with B 用B盖住A / be covered with 被。
覆盖7.one third （三分之一）/ two thirds（三分之二）子基母序，分子超过一，分母加s8.half of… 。
的一半(主语看后面名词)9.flow into / run into 流入。
10.t he sun rises in the east太阳从东方升起/ raise your hand 举手11.f rom A to B 从A到B12.b rush one’s teeth 刷牙13.l eave … on 让。
处于开着的状态14.p our into 倒入15.t urn on/ off = switch on/off 打开/ 关掉turn up 调大/ turn down 调小16.v oice 人的声音/ noise 噪音/ sound 声音17.l ook around 环视周围18.w aste time （in）doing sth / on sth 浪费时刻做某事19.s ound angry ---- look/ smell / taste / sound / feel + 形容词（比较级）be / become/ go/ get/ turn/ keep/ make +形容词（比较级）much / even / far / any / a little / a bit/ no/ still + 比较级20.i t’s easy for you to do sth 做。
chap1-digitalconcepts
Digital Fundamentals, 9e
Digital : A digital quantity is one having a discrete set of values 数字：一个数字量是有一组离散值
Figure 1–2 Sampled-value representation (quantization) of the analog quantity in Figure 1–1. Each value represented by a dot can be digitized by representing it as a digital code that consists of a series of 1s and 0s.采样值表示（量化）在
Each value represented by a dot in figure 1-2 can be digitized by representing it as a
Binary digits
• In digital circuits, two different voltage levels are used to represent the two bits. 在数字电路中，两个不同的电压等级是用来表示 两个位 In positive logic (正逻辑）：LOW=0, HIGH=1 In negative logic(负逻辑）: HIGH=0,LOW=1
Figure 1–11 Example of a timing diagram.
Thomas L. Floyd
Digital Fundamentals, 9e
Copyright ©2006 by Pearson Education, Inc. Upper Saddle River, New Jersey 07458 All rights reserved.
英语国家概况第一章
Chapter1Land and PeopleGreat Britain is the largest island in Europe. It is made up of England, Scotland, and Wales.Together with Northern Ireland, it forms the United Kingdom of Great Britain and Northern lreland. This is the full name of the country which constitutes all these places. The United Kingdom of Great Britain and Northern Ireland, or the United Kingdom, is “the UK" for short. However,most people call the UK ”Britain" or “Great Britain,” and some people simply say “England," which is incorrect and particularly annoys the Scots.According to the 2011 census, the total population of the UK was around 63 million. It is the third-largest in the European Union (behind Germany and France) and the 22nd-largest in the world.The UK is a developed country. According to 2013 statistics it has the sixth-largest national economy in the world (and third-largest in Europe) measured by nominal GDP and eighth-largest in the world (and second-largest in Europe) measured by purchasing power parity (PPP). It was the world's first industrialized country and the world's foremost power during the 19th and early 20th centuries. The UK remains a great power because it still has considerable economic,cultural,military,scientific and political influence internationally.The capital of the UK is London, which is among the world's leading commercial, financial,and cultural centers. Other major cities include Birmingham,Liverpool, and Manchester in England, Belfast and Londonderry in Northern Ireland, Edinburgh and Glasgow in Scotland, and Swansea and Cardiff in Wales.I.Geographical Features1. The UK's Geographical Location and Its SizeThe UK is bordered on the south by the English Channel. It is bordered on the east by the North Sea, and on the west by the Irish Sea and the Atlantic Ocean. The UK's only land border with another nation is between Northern Ireland and Ireland.The UK is separated from the rest of Europe by the English Channel. The English Channel between England and France is quite narrow and the narrowest part is called the Suraits of Dover, which is only 33 km across. In 1985 the British government and the French government decided to build a channel tunnel under the Straits of Dover so that England and France could be joined together by road. After eight years of hard work this channel tunnel, which is called"Chunnel,” was open to traffic in May 1994.The UK covers a total area of 244,110 sq km. lt runs 1,000 km from north to south and extends,at the widest part, about 500 km. So no part of the UK is very far from the coast and it provides a valuable resource. The British coast is long and has good, deep harbors. Sea routes extend far inland, providing cheap transportation.England is the largest, most populous, and wealthiest division of the UK. It makes up 130,400 sq km of the UK's total area.The area of Scotland is 78,800 sq km, the area of Wales is20,800 sq km, and the area of Northern Ireland is 14,100 sq km.This means that England makes up 53.4% of the area of the UK, Scotland 32.3%, Wales 8.5%, and Northern Ireland 5.8%.2.Rivers and LakesSince the UK has a moist climate with much rainfall, it has many rivers and lakes.Rivers in central and eastern Britain tend to flow slowly and steadily all year long because they are fed by the frequent rain. Many have been navigable, and from the earliest times they have served peoples interested in either commerce or invasion. The Highlands act as a divide and determine whether rivers flow west to the Irish Sea or east to the North Sea.Rivers and streams moving westward down from the Highlands tend to be swift and turbulent; rivers flowing eastward tend to be long and gentle, with slowly moving waters.The Thames and the Severn are the longest rivers in Britain and are almost equal in length. The Severn flows south out of the mountains of central Wales to the Bristol Channel at Bristol. It is 354 km long. The Thames,338 km long, flows eastward out of the Cotswold Hills and weaves through the metropolis of London. The Thames provides water to the city of London and is used to carry commercial freight. Other important rivers in England are the Mersey,which enters the Irish Sea at Liverpool; the River Humber on the east coast,into which the Trent River and several other rivers flow; and the Tyne River in northern England,which flows past Newcastle upon Tyne to the North Sea.In Scotland the important rivers are the Clyde and the Forth, which are joined by a canal. The River Clyde flows northwest, past Glasgow, and empties into the Atlantic at the Firth of Clyde. (Firth is the Scottish name for an arm of the sea that serves as the broad estuary of a river.) The River Forth flows eastward into the Firth of Forth, where Edinburgh rises on its south bank.The most important rivers in Northern Ireland are the Lagan, the Bann, and the Foyle.Most of the large lakes in the UK are located in the upland areas of Scotland and northern England,although Lough Neagh in Northern Ireland is the largest lake in the UK. Loch Lomond, on the southwestern edge of the Highlands of Scotland, is the largest on the island of Great Britain, measuring 37 km long and from 1.6 to 8 km ke Windermere is the largest of 15 major lakes in the famous Lake District of northwestern England.It is about 1.6 km wide and more than 16 km long.Ⅱ.Climate1.A Maritime ClimateWhen we say climate we mean the average weather conditions at a certain place over a period of years.We don’t mean the day-to-day weather conditions at a certain place. Though it seems that people are always complaining about the weather in the UK because it is rainy and so changeable and unpredictable,the climate in the UK is in fact a favorable one. The UK has a maritime climate. Winters are mild,not too cold and summers are cool,not too hot.It has a steady reliable rainfall throughout the whole year.It has a small range of temperature.The average temperature in winter in the north is 4—6℃and in summer in the south is 12—17℃.So even in winter one can still see stretches of green grass in the open country,in the parks and round the houses.2.Factors Which Influence the ClimateThe UK is an island country which lies between latitude 50°to 60°north. It lies farther north than even the northernmost par of Heilonjiang Province of China. Compared with other countries of the same latitudes it has a more moderate climate. This is influenced mainly by three factors:(1)The surrounding waters tend to balance the seasonal differences by heating up the land in winter and cooling it off in summer. As the sea heats up and cools off relativelyb slowly it brings warm air in winter and cool air in summer.(2)The prevailing southwest winds or the Westerlies (winds which come from the west) blow over the country all the year round, bringing warm and wet air in winter and keeping the temperatures moderate.(3) The North Atlantic Drift, which is a warm current, passes the western coast of the British Isles and warms them.Since the UK's climate is of the maritime type, it is characterized by cool temperatures, frequent cloudy days and rainstorms. It changes from day to day, and this makes it difficult to forecast. It is so changeable that sometimes one can experience four seasons in the course of a single day. Day may break as a fine spring morning; an hour or so later black clouds may have appeared from nowhere and rain may be pouring down. At midday conditions may really be wintery with the temperatures down to about 8 °C. Then in the Jater atfternoon the sky will be clear, the sun will begin to shine again, and for an hour or two before darkness falls, it will be summer. It has been said that the uncertainty about the weather has had a definite effect upon the Englishman's character. It tends to make him cautious, for example. You may laugh when you see an Englishman going out on a brilliantly sunny morning wearing a raincoat and carrying an umbrella. However, most frequently it comes in drizzles and you don't necessarily need an umbrella.3.RainfallThe UK has a steady reliable rainfall throughout the whole year.The average annual rainfall in the UK is over 1,000 mm. It has 750 mm to 1,250 mm of rainfall along the coast in the east and south except a small area in the southeastern corner of the country which receives less than 750 mm. In the west there is as much as 1,250 mm to 2.000 mm of rainfall and in some areas in the northwest it is over 2,000 mm.The Westerlies blow over the UK all the year round, bringing warm and wet air from the Atlantic Ocean. They rise, climb the highlands and the mountains in the west, become colder and then cause heavy rainfall. There is not so much rainfall in the east because after climbing over the highlands and mountains the air gets warmer and drier when it descends and does not give so much rain.As a result of the rainfall distribution in Britain there is a water surplus in the north and west, and a water deficit in the south and east. Reservoirs have therefore to be built in such highland areas as Central Wales,the Lake District and the Scottish Highlands, so that water can be stored here and then transferred to the more populated and industrial areas of lowland Britain.Generally speaking,the climate in the UK is favorable and equable (neither too hot nor too cold).Extremes of heat or cold, or of drought or prolonged rainfall are rarely experienced. It is estimated that on average about 3-6 cubic meters of rain per person per day fall over the UK. Thisis far more than is needed,but problems still remain. Sometimes there are several months of drought, and at other times too much rain causes flooding. Fog,smog, frost and severe gales are not uncommon and often cause great damage to crops and to people's life. In 1952 the sulphur dioxide in the four-day London smog,an unhealthy atmosphere formed by mixing smoke and dirt with fog, left 4,000 people dead or dying.Since then most cities in the UK have introduced “clean air zones” whereby factories and households are only allowed to burn smokeless fuel.Although the UK does not experience hurricanes, that is,storms with a strong fast wind such as typhoons or cyclones, many areas are subjected to severe gales, especially in winter.III.Plant and Animal Life1.Plant LifeThe mild climate,ample rain, and long growing season in the UK support a great variety of plants,which grow exceptionally well. Most of the UK was once covered with thick,deciduous forests in which oak trees predominated.(Deciduous trees are those that lose their leaves every year.)The impact of centuries of dense human polpulation has massively altered the flora of the UK, and only tiny remnants of these forests remain today.Before they were affected by centuries of clearing and human use, the great oak forests spread over the best soils in Britain. Forests were unable to establish themselves in the poorer soils of the mountains,wetlands,heath,and moorlands.The plants common to these wilder areas are heather,gorse and peat moss.These regions have been altered by heavy grazing of livestock and by controlled burning.Controlled burning creates environments suitable for game birds,which feed on the shoots of the new covered by towns and farmland.The marginal wetlands that remain continue to be threatened by reclamation for farms and homes,and some wetland plant species now grow only in conservation areas.2. Animal LifeBritain has many smaller mammals, and the larger ones tend to be gentle. The only surviving large mammals are red deer, which live in the Scottish Highlands and in Exmoor in southwestern England, and roe deer, foud in the woodlands of Scotland and southern England. At one time boars (wild pigs) and wolves roamed Britain, but they were hunted to extinction.Many smaller mammals inhabit Britain, including foxes,otters, red squirrels, and wildcats. Otters are found mainly in southwestern England and in the Shetland and Orkney islands.The red squirrel, driven out of most of its range by the imported gray squirrel, is now limited mainly to the Isle of Wight and Scotland. Wildcats are found only in parts of Scotland.Bird-watching is a popular national pastime. Britain is home to a large variety of birds, due in lange measure to its position as a focal point of a migratory network.Saltwater fish were once important to Britain's economy. Cod, herring and mackerel are still caught off the coasts of Britain, although quotas are now imposed. Lobster, crab,and other shellfish are caught along inshore waters.IV. People1.Ethnic GroupsFor centuries people have migrated to the British Isles from many parts of the world,some to avoid political or religious persecution, others to find a better way of life or to escape poverty. In historic times migrants from the European mainland joined the indigenous population of Britain during the Roman Empire and during the invasions of the Angles,Saxons,Jutes,Danes,and Normans. The Irish have long made homes in Great Britain.Many Jews arrived in Britain toward the end of the 19th century and in the 1930s. After 1945 large numbers of other European refugees settled in the country. The large immigrant communities from the West Indies and South Asia date from the 1950s and 1960s. There are also substantial groups of Americans, Australians, and Chinese, as well as various other Europeans, such as Greeks, Russians,Poles, Serbs, Estonians, Latvians, Armenians,Turkish Cypriots, Italians, and Spaniards. Beginning in the early 1970s, Ugandan Asians and immigrants from Latin America, Southeast Asia, and Sri Lanka have sought refuge in Britain. People of Indian, Pakistani, and Bangladeshi origin account for more than half of the total ethnic minority population, and people of West Indian origin are the next largest group. The foreign-born element of the population is concentrated in inner-city areas, and more than half live in Greater London.nguagesOf the surviving languages the earliest to arrive in Britain were the two forms of Celtic: the Goidelic (from which Irish, Manx, and Scottish Gaelic derive) and Brythonic (from which the old Cornish language and modern Welsh have developed). Among the contemporary Celtic languages Welsh is the strongest: about one-fifth of the total population of Wales are able to speak it. Scottish Gaelic is strongest among the inhabitants of the islands of the Outer Hebrides and Skye, although it is still heard in the nearby North West Highlands.In Northern Ireland very little Irish is spoken. The last native speakers of Cornish died in the 18th century.The second link with Indo-European is through the ancient Germanic language group, two branches of which, the North Germanic and the West Germanic, were destined to make contributions to the English language. Modern English is derived mainly from the Germanic dialects spoken by the Angles, Saxons, and Jutes (who all arrived in Britain in the 5th century AD) and heavily influenced by the language of the Danes (Vikings), who began raiding the British Isles in about 790 and later colonized parts of northern and eastern England.Under the Norman and Angevin kings, England formed part of a continental empire,and the prolonged connection with France retained by its new rulers and landlords made a deep impression on the English language. Many additions to the English language have been made since the 14th century,but the Normans were the last important linguistic group to enter Britain.3.ReligionThe various Christian denominations in the UK have emerged from schisms that divided the church over the centuries.The greatest of these occurred in England in the 16th century, when Henry VIII rejected the supremacy of the Pope. This break with Rome facilitated the adoption of some Protestant tenets (a principle or belief held by a person) and the founding of the Church of England,still the state church in England,although Roman Catholicism has retained adherents (supporters).In Scotland the Reformation gave rise to the Church of Scotland,which was governed by presbyteries—local bodies composed of ministers and elders—rather than by bishops,as was the case in England.Roman Catholicism in Ireland as a whole was almost undisturbed by theseevents,but in what became Northern Ireland the Anglican and Scottish (Presbyterian) churches had many adherents.The British tradition of religious tolerance has been particularly important since the 1950s, when immigrants began to introduce a great variety of religious beliefs.There are large and growing communities that pactice Islam, Hinduism, and Sikhism.The largest number of Muslims came from Pakistan and Bangladesh.,The lange Sikh and Hindu communities originated in India. There are also many Buddhist groups.4.UrbanizationBy any standard the UK is among the most urbanized of countries. The greatest overall change that accompanied Britain's early industrial development was, in fact, the large-scale urbanization. The increasing percentage of employees in offices and service industries ensures continued urban growth, Of every 10 people in the UK, nine live in towns and more than three of them in one of the country's 10 largest metropolitan areas. The Greater London metropolitan area—the greatest port, the largest center of industry, the most important center of office employment, and the capital city—is by far the largest of these. The need for accommodating business premises (offices) has displaced population from Inner London, and this outward movement, in part, has led to the development of new towns outside the 16-km-wide Green Belt that surrounds London's built-up area.Large metropolitan areas also formed in industrial areas during the 19th and early 20th centuries.Although coalfields or textile manufacture started the initial growth of many of these urban areas, coal mining had virtually ceased in all of them by the end of the 20th century, and heavy industry and textile production had given way to a more diverse form of manufacturing and service activities. Birmingham dominates the extensive built-up area of the West Midlands metropolitan area,but the industrial Black Country—named for its formerly polluted skies and grimy buildings—also has several large and flourishing towns.In Greater Manchester, with a similar number of inhabitants, urbanization accompanied the mechanization of the cotton textile industry. Across the Pennines similar mechanization of wool textiles created the West Yorkshire metropolitan area, with Leeds and Bradford as its twin centers. The metropolitan area of Tyne and Wear (centered on Newcastle upon Tyne) and the Greater Glasgow metropolitan area are also located on coalfields. Greater Glasgow has about one-third of Scotland's people. Merseyside (centered on Liverpool) has traditionally served as a seaport and distribution center for Greater Manchester and the rest of Lancashire.Other large metropolitan areas in Great Britain include South Yorkshire(centered on Sheffield),Nottingham,and Bristol.About one-fifth of Northern Ireland’s people live in Belfast.In addition to these large metropolitan areas,there are many other minor urban areas and large towns,several of which line the coast.With so much urban and suburban concentration, the problems of air,water,and noise pollution have caused much concern in the UK. Clean-air legislation has brought considerable progress in controlling air pollution.Smoke-control areas have been established in most cities and towns, and there has been a shift from coal to cieaner fuels.Pollution of the rivers remains a large problem, particularly in the highly industrialized parts of the UK, but vigilance,research, and control by the National River Authorities and general public concern for the environment are encouraging features of contemporary Britain.5. Population GrowthFrom the 18th century until well into the 19th century, Britain's population soared as the death rate dropped and the birth rate remained high. During this period the total population increased from about 6 million in the 1760s to 26 million in the 1870s. Toward the end of the 19th century and into the 20th century the birth rate stabilized and the death rate remained low. The population took on the characteristics of a modern, developed,and prosperous state. Family size decreased and the median age of the population pared to the rest of the world, the UK has a smaller percentage of younger people and a higher percentage of older people, with more than 20% over the age of 60; those under the age of 15 make up only 13% of the population. Britain's population has been growing slowly, slower than the average for countries in the European Union (EU).6. Migration PatternsBeginning in the 1950s, the immigration of nonwhite(“New Commonwealth") people from such developing nations as India, Pakistan, and the countries of the West Indies became significant, and from 1957 until 1962 there was a net migration gain. Since then restriction on the entry of New Commonwealth citizens has decreased the primary inflow,but dependents of immigrants already in the UK are still admitted. The reasons for restricting entry were in part economic but were also associated with the resistance of the existing population to the new arrivals. Nevertheless, thc UK continues to gain people from the New Commonwealth.Migration within the UK has at times been sizable. Until 1700 the relatively small population was sparsely distributed and largely rural and agricultural, much as it had been in medieval times. From the mid-18th century, scientific and technological innovations created the first modern industrial state.At the same time, agriculture underwent technical and tenurial changes that allowed increased production with a smaller workforce, and revolutionary improvements in transport made the movement of materials and people easier. As a result,by the late 19th century a mainly rural population had largely become a nation of industrial workers and town dwellers.Industry, as well as the urban centers that inevitably grew up around it, concentrated near the coalfields,while the railway network, which grew rapidly ather 1830,enhanced the commercial importance of many towns.The migration of people,especially young people, from the country to industrialized towns took place at an uprecedented rate in the early railway age, and such movements were relatively confined geographically.Migration from agricultural Ireland was an exception, for, when the disastrous potato disease of 1845-1849 led to widespread famine, large numbers moved to Great Britain to become urban workers in Lancashire,Clydeside (the Glasgow region), and London.The rural exodus (a lot of people leaving a place at the same time) went on, but on a greatly reduced scale after 1901.Soon after World War I, new interregional migration flows began when the formerly booming 19th-century industrial and mining districts lost much of their economic momentum. Declining heavy industry in Clydeside, northeastern England, South Wales, and parts of Lancashire and Yorkshire caused a lot of people to lose jobs, and many migrated to the relatively more prosperous Midlands and southern England. This movement of people continued until it was checked by the relatively full employment conditions that occurred soon after the start of World War II.In the 1950s job opportunities in the UK improved with government sponsored diversification of industry, reducing the volume of migration to the south. The decline of certain northern industries—coal mining, shipbuilding, and cotton textiles in particular—had nevertheless reached a critical level by the late 1960s, and the emergence of new growth points in the West Midlands and southeastern England made the drift to the south a continuing feature of British economic life. During the 1960s and 1970s the areas of most rapid growth were East Anglia, the South West, and the East Midlands, partly because of limitations on growth in Greater London and the development of new towns in surrounding areas.During the 1980s the government largely abandoned subsidies for industry and adopted a program of rationalization and privatization. This resulted in the collapse of coal mining and heavy industry in the north and the West Midlands of England and in the Lowlands of Scotland and a similar loss of heavy industry in Northern Ireland, thus creating a wave of migration from these regions to the more prosperous south of England, especially East Anglia,the East Midlands,and the South West.As the economy became stable during the 1990s,migration from Scotland, Northern Ireland, and northern England decreased.While the South East (including Greater London) was the chief destination of external immigrants into Britain, this region, along with the West Midlands, produced a growing internal migration to surrounding regions of England during the 1990s. This pattern reflected a larger trend of migration out of older urban centers throughout Britain to surrounding rural areas and small towns at the end of the 20th century.。
语用学第一章
• Definition 2: • Pragmatics is the study of all those aspects of meaning not captured in a semantic theory. • 语用学是对所有那些未能纳入语意理论 的意义侧面的研究。
• Definition 3: • Pragmatics is the study of the relations between language and context that are basic to an account of language understanding. • 语用学是对语言和语用之间对于说明语 言理解来说是十分根本的那些关系的研 究。
Component vs. perspective分相论与 综观论
• • Component view of pragmatics Davis points out in his book Pragmatics: A Reader(1991) that pragmatics, like phonetics, phonology, morphology, syntax and semantics, is a component of linguistics. • Perspective view of pragmatics Verschueren(1999) proposes that pragmatics is not a component of linguistics, but a new way of looking at language. Pragmatics is specified as “a general cognitive, social, and cultural perspective on linguistic phenomena in relation to their usage in forms of behavior”(Verschueren,1999) 语用学是语言各个方面的功能总览, 即研究人类生活中语言的 认知、社会和文化的功能。
语言学第一章
语言学第一章Chapter 1 Invitation to linguistics1.1 Why study language?1. Language is very essential to human beings.2. In language there are many things we should know.3. For further understanding, we need to study language scientifically.1.2 What is language?Language is a means of verbal communication. It is a system of arbitrary vocal symbols used for human communication.1.3 Design features of languageThe features that define our human languages can be called design features which can distinguish human language from any animal system of communication.1.3.1 ArbitrarinessArbitrariness refers to the fact that the forms of linguistic signs bear no natural relationship to their meanings.1.3.2 DualityDuality refers to the property of having two levels of structures, such that units of the primary level are composed of elements of the secondary level and each of the two levels has its own principles of organization.1.3.3 CreativityCreativity means that language is resourceful because of its duality and its recursiveness.Recursiveness refers to the rule which can be applied repeatedly without any definite limit. The recursive nature of language provides a theoretical basis for the possibility of creating endless sentences.1.3.4 DisplacementDisplacement means that human languages enable their users to symbolize objects, events and concepts which are not present (in time and space) at the moment of conversation.1.4 Origin of language1. The bow-wow theoryIn primitive times people imitated the sounds of the animal calls in the wild environment they lived and speech developed from that.2. The pooh-pooh theoryIn the hard life of our primitive ancestors, they utter instinctive sounds of pains, anger and joy which gradually developed into language.3. The “yo-he-ho” theoryAs primitive people worked together, they produced some rhythmic grunts which gradually developed into chants and then into language.1.5 Functions of languageJacobson——language has six functions:1. Referential指称功能: to convey message and information;2. Poetic: to indulge in language for its own sake;3. Emotive: to express attitudes, feelings and emotions;4. Conative意动功能: to persuade and influence others through commands and entreaties;5. Phatic寒暄功能: to establish communion with others;6. Metalingual元语功能: to clear up intentions, words and meanings.Halliday ——that language has three metafunctions:1. Ideational function: to convey new information, to communicate a content that is unknown to thehearer;2. Interpersonal function: embodying all use of language to express social and personal relationships;3. Textual function: referring to the fact that language has mechanisms to make any stretch of spokenand written discourse into a coherent and unified text and make a living passage different from a random list of sentences.Hu Zhuanglin——language has at least seven functions:1.5.1 InformativeThe informative function means language is the instrument of thought and people often use it to communicate new information.1.5.2 Interpersonal functionThe interpersonal function means people can use language to establish and maintain their status in a society.1.5.3 Performative施为功能The performative function of language is primarily to change the social status of persons, as in marriage ceremonies, the sentencing of criminals, the blessing of children, the naming of a ship at a launching ceremony, and the cursing of enemies.1.5.4 Emotive functionThe emotive function is one of the most powerful uses of language because it is so crucial in changing the emotional status of an audience for or against someone or something.1.5.5 Phatic communionThe phatic communion means people always use some small, seemingly meaningless expressions such as Good morning, God bless you, Nice day,etc., to maintain a comfortable relationship between people without any factual content.1.5.6 Recreational functionThe recreational function means people use language for the sheer joy of using it, suc h as a baby’s babbling or a chanter’s chanting.1.5.7 Metalingual functionThe metalingual function means people can use language to talk about itself. E.g. I can use the word “book” to talk about a book, and I can also use the expression “the word book” t o talk about the sign “b-o-o-k” itself.1.6 What is linguistics?Linguistics is the scientific study of language. It studies not just one language of any one community, but the language of all human beings.1.7 Main branches of linguistics1.7.1 PhoneticsPhonetics is the study of speech sounds, it includes three main areas: articulatory phonetics, acoustic phonetics, and auditory phonetics.1.7.2 PhonologyPhonology studies the rules governing the structure, distribution, and sequencing of speech sounds and the shape of syllables.1.7.3 MorphologyMorphology studies the minimal units of meaning –morphemes and word-formation processes.1.7.4 SyntaxSyntax refers to the rules governing the way words are combined to form sentences in a language, or simply, the study of the formation of sentences.1.7.5 SemanticsSemantics examines how meaning is encoded in a language.1.7.6 PragmaticsPragmatics is the study of meaning in context.1.8 MacrolinguisticsMacrolinguistics is the study of language in all aspects, distinct from microlinguistics, which dealtsolely with the formal aspect of language system.1.8.1 Psycholinguistics心理语言学Psycholinguistics investigates the interrelation of language and mind, in processing and producing utterances (and in language acquisition for example).1.8.2 Sociolinguistics社会语言学Sociolinguistics is the study of the characteristics of language varieties1, the characteristics of their functions2, and the characteristics of their speakers3. (123相互作用构成一个speech community 语言社团)1.8.3 Anthropological linguistics人类语言学Anthropological linguistics studies the history and structure of formerly unwritten language, the emergence of language and the divergence of languages.1.8.4 Computational linguistics计算语言学Computational linguistics is an interdisciplinary field which centers around the use of computers to process or produce human language.1.9 Important distinctions in linguistics1.9.1 Descriptive描写vs. Prescriptive规定A linguistic study is descriptive if it describes and analyses the facts observed.It is prescriptive if it tries to lay down rules for the “correct” use of language.1.9.2 Synchronic共时vs. Diachronic历时The description of a language at some point in time is a synchronic study.The description of a language as it changes through the time is a diachronic study.The distinction between synchronic and dischronic studies is only theoretically clear.原因：①Languages are in a constant state of changing.②The language of any speech community is never uniform.③When a language changes, one set o f features are not suddenly replaced by another set of features.1.9.3 Langue 语言& parole言语Saussure distinguished the linguistic competence of the speaker and the actual phenomena or data of linguistics as langue and parole.Langue refers to the abstract linguistic system shared by all the members of a speech community.Parole refers to the actualized language, or realization of langue.区别：①Langue is abstract but parole is specific to the situation in which it occurs.②Langue is not actually spoken by anyone; parole is alwaysa naturally occurring event.③Langue is relatively stable and systematic; parole is subject to personal and situational constraints.1.9.4 Competence and performanceAccording to Chomsky, a language user’s underlying knowledge about the system of rules is called the linguistic competence, and the actual use of language in concretesituations is called performance.Competence is the ideal language user`s knowledge of the rules of his language.Performance is the actual realization of this knowledge in utterances.。
专业英语翻译第一章
注：电气工程及其自动化专业英语翻译 1~7面班级：1002班学号：20姓名：王定瑞PART 1 FUNDAMENTALS OF ELECTRIC ENGINEERINGChapter 1 Circuit Fundamentals第1部分的电气工程基础第1章电路原理Electrostatic Charges静电荷Protons and electrons are parts of atoms that make up all things in our world. The positive charge of a proton is similar to the negative charge of an electron. However, a positive charge is the opposite of a negative charge. These charges are called electrostatic charges. Each charged particle is surrounded by an electrostatic field.质子和电子部件的原子构成一切事物在我们的世界。
正电荷的质子是类似于负电荷的电子。
然而,一个正电荷的反面是一个负电荷。
这些指控被称为静电荷。
每个带电粒子周围是一个静电场。
The effect that electrostatic charges have on each other is very important. They either repel (move away) or attract (come together) each other. It is said that like charges repel and unlike charges attract.这个效应,静电指控对方是非常重要的。
他们要么排斥(离开)或吸引(一起)每个其他。
哈利波特英文学习 哈利波特与魔法石之第一章 大难不死的男孩
Chapter 1 The Boy Who Lived 大难不死的男孩Mr. and Mrs. Dursley, of number four, PrivetDrive女贞路, were proud to骄傲say that they were perfectly normal, thank you very much. They were the last people (最后一个…的人，即最不希望…的人)you'd expect to希望be involved被卷入in anything strange奇怪的or mysterious神秘故事, because they just didn't hold with such nonsense. (因为他们根本不相信这种无稽之谈)Mr. Dursley was the director老板of a firm called Grunnings, which made drills钻机. He was a big, beefy man with hardly几乎没有any neck, although he did have a very large mustache胡子. Mrs. Dursley was thin and blonde金发and had nearly twice the usual amount of neck, which came in very useful as she spent so much of her time craning over 伸长脖子透过garden fences围栏, spying on偷窥the neighbors. The Dursleys had a small son called Dudley and in their opinion(在他们看来) there was no finer boy anywhere. The Dursleys had everything they wanted, but they also had a secret 秘密, and their greatest fear最大的担心was that somebody would discover it. They didn't think they could bear it if anyone 住在四号普里怀特街的杜斯利先生及夫人，非常骄傲地宣称自己是十分正常的人。
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典型的编译程序具有7个逻辑部分 典型的编译程序具有 个逻辑部分 S.P 词法分析程序 符 号 表 管 理 语法分析程序 语义分析、生成中间代码 代码优化 生成目标程序 O.P
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出 错 处 理
1.3.2 遍（PASS） 遍：对源程序（包括源程序中间形式）从头到尾扫描一次， 并做有关的加工处理 ，生成新的源程序中间形式或目标程序， 通常称之为一遍。 第一遍 第二遍 S.P C1 S.P
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三地址指令） 四元式（三地址指令 三地址指令 对于前面提到的例子 X1:= (2.0+ 0.8 ) * C1 运算符
(1) (2)
左运算对象
右运算对象
结果
+ *
2.0 T1
(3) :=
X1 其中T1和T2为编译程序引入的工作单元
0.8 C1 T2
T1 T2
四元式的语义为： 2.0 + 0.8 → T1 T1 * C1 → T2 T2 → X1 这样所生成的四元式与原来的赋值语句在语言的 形式上不同，但语义上等价。
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例： X1:= (2.0+ 0.8 ) * C1 由语法分析识别出为赋值语句，语义分析首 先要分析语义上的正确性，例如要检查表达式中 和赋值号两边的类型是否一致。 根据赋值语句的语义，生成中间代码。即用 一种语言形式来代替另一种语言形式，这式翻译 的关键步骤。（翻译的实质：语义的等价性） 下面介绍一种常用的中间代码来替换上述的赋值 语句
•编译程序 编译程序
若源程序是用高级语言书写，经加工后得到目标程序，上述 翻译过程称“编译”（Compile) 汇编程序与编译程序都是翻译程序，主要区别是加工对象的 不同。由于汇编语言格式简单，常与机器语言之间有一一对 应的关系。汇编程序所要做的翻译工作比编译程序简单的多。
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源程序的编译和运行
• 编译或汇编阶段
1.5 编译技术的应用 语法制导的结构化编译器 程序格式化工具 软件测试工具 程序理解工具 高级语言的翻译工具 等等。 等等。
作业： 作业：第13页1、2题 页 、 题
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• 要求： 要求：
– 提前预习，上课认真听讲； 提前预习，上课认真听讲； – 课后即时复习，认真完成作业。 课后即时复习，认真完成作业。
辅导老师：。 辅导老师：。
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第一章
概论
(介绍名词术语、了解编译系统的结构和编译过程） 介绍名词术语、了解编译系统的结构和编译过程） 介绍名词术语
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内
容
1.1.编译的起源：程序设计语言的发展 .编译的起源： 1.2. 基本概念 1.3. 编译过程和编译程序构造 1.4. 编译技术的其他应用
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四、代码优化 任务：目的是为了得到高质量的目标程序。 例如：上面的四元式中第一个四元式是计算常 量表达式值，该值在编译时就可以算出并存放在工 作单元中，不必生成目标指令来计算，这样四元式 可优化为： 编译时： * := 2.0 + 0.8 → T1 T1 *1 C1 T2
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T2
五、生成目标程序
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1.1 基本概念
• 低级语言（Low level Language) 低级语言（
– 字位码、机器语言、汇编语言 字位码、机器语言、 –特点：与特定的机器有关，功效高，但使用复杂、繁 琐、费时、易出错
• 高级语言 -- Fortran、Pascal、C 语言等 、 、
–特点：不依赖具体机器，移植性好、对用户要求低、 易使用、易维护等。
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1 2 3 4
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6 7 8 9
二、语法分析
任务：根据语法规则（即语言的文法），分析并识别出 各种语法成分，如表达式、各种说明、各种语句、 过程、函数程序等，并进行语法正确性检查。 例如，对于前面提到的例子X1:= (2.0+ 0.8 ) * C1 我们可以 根据语言赋值语句的文法来分析和识别该语句（单词串）。首先 给定文法： <赋值语句>→<变量><赋值操作符><表达式> <变量>→<简单标识符> <赋值操作符>→:= <表达式>→ …… 语法分析根据文法，将<变量>、<赋值操作符>、<表达式>识 别出来，进而将赋值语句识别出来，在识别过程中进行语法检查， 若有错误，则应输出出错信息。
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•源程序 源程序
用汇编语言或高级语言编写的程序称为源程序
•目标程序 目标程序
用目标语言所表示的程序 目标语言：可以是介于源语言和机器语言之间的“中间 语言”，可以是某种机器的机器语言,也可以是某机器的汇 编语言。
•翻译程序 翻译程序
将源程序转换为目标程序的程序称为翻译程序。它是 指各种语言的翻译器，包括汇编程序和编译程序，是汇编 程序、编译程序以及各种变换程序的总称。
编译技术
邵兵
shaobing@
博士 副教授
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课程要求 课时:48学时 课时:48学时 :48
:(分别计分) 分为两部分:(
–理论基础:70%,课堂教学，按时交作业,闭卷考试 理论基础:70%,课堂教学，按时交作业, 理论基础:70%,课堂教学 –实践部分:30%,上机实践(50机时) 实践部分:30%,上机实践(50机时) 实践部分:30%,上机实践(50机时
S.P
词法分析 程序
语法分析 程序
语义分析 生成中间 代码
代码优化 程序
生成目标 程序
O.P
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在上列五个阶段中都要做两件事： （1）建表和查表；（2）出错处理； 所以编译程序中都要包括表格管理和出错处理两部分 表格管理（符号表组织） 在整个编译过程中始终都要贯穿着建表（填表）和查表的工 作。即要及时的把源程序中的信息和编译过程中所产生的信息登 记在表格中，而在随后的编译过程中同时又要不断的查找这些表 格中的信息。 出错处理 规模较大的源程序难免有多种错误，编译程序必须要有出错 处理的功能。即能诊察出错误，并能报告用户错误性质和位置， 以便用户修改源程序。出错处理能力的优劣是衡量编译程序质 量好坏的一个重要指标。
源程序 编译程序 或汇编程序 目标程序
• 运行阶段
输入数据 目标程序 + 运行子程序 输出数据
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•解释程序（Interpreter） 解释程序（ 解释程序 ） 对源程序进行解释执行的程序。 • 工作过程 源程序
输入数据
解释程序
输出数据
• 特点、与编译程序比较 特点、
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“编译-解释执行”系统 编译-解释执行”
取单词 返回单词 词法分析 整理目标程序 停机 语法分析 语法成分 返回分析结果 语义分析生成 目标程序
O.P.
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1.3.3 前端和后端 根据编译程序各部分功能，将编译程序分成前端和后端。 前端：通常将与源程序有关的编译部分称为前端。 前端 词法分析、语法分析、语义分析、中间代码生成、 代码优化 -------分析部分 特点：与源语言有关 后端：与目标机有关的部分称为后端。 后端 目标程序生成（与目标机有关的优化） -------综合部分 特点：与目标机有关
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1.4 编译程序的前后处理器
源程序：多文件、宏定义和宏调用，包含文件 源程序 目标程序：一般为汇编程序或可重定位的机器代码 目标程序
框架源程序 预处理器 源程序 编译程序 目标程序（汇编） 目标程序（汇编） 汇编程序 可运行的机器代码 可重定位机器码 文件） （Obj文件） 文件
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可重定位机器码 文件组） （文件组） 连接编译 可重定位机器码 加载器 库目标、可重 库目标、 定位目标文件
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源程序、翻译程序、目标程序 三者关系： 源程序
SOURCE PROGRAM
翻译程序
TRANSLATER
目标程序
OBJECT PROGRAM
即源程序是翻译程序的输入，目标程序是翻译程序的输出
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•汇编程序 汇编程序
若源程序用汇编语言书写，经过翻译程序得到用机器语言 表示的程序，这时的翻译程序就称之为汇编程序，这种翻译过 程称为“汇编”(Assemble）
目的: 目的
掌握编译的基本理论、常用的编译技术，了解编译过 程及编译系统的构造（结构和机理）。能运用所学技 术解决实际问题，能独立编写一个小型编译系统。
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• 教材和参考书
– 高仲仪、金茂忠，《编译原理及编译程序构造》，北航出版社 高仲仪、金茂忠， 编译原理及编译程序构造》 。 – 高仲仪、蒋立源，《编译技术》，西北工业大学出版社。 高仲仪、蒋立源， 编译技术》 西北工业大学出版社。 – 吕映芝，张素琴等，《编译原理》，清华大学出版社，1998，1 吕映芝，张素琴等， 编译原理》 清华大学出版社， ， 。
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语义分析、 三、语义分析、生成中间代码
任务：对识别出的各种语法成分 进行语义分析，并产生相应的中间代码。
•中间代码：一种介于源语言和目标语言之间的中间语言形式。 • 生成中间代码的目的： <1> 便于做优化处理； <2> 便于编译程序的移植（中间代码不依赖与目标计 算机）。 •中间代码的形式：编译程序设计者可以自己设计，常用的有 四元式、三元式、逆波兰表示等。
由中间代码很容易生成目标程序（地址指令序列）。这 部分工作与机器关系密切 ，所以要根据机器进行。在做这 部分工作时（要注意充分利用累加器），也可以进行优化 处理。
注意：在翻译成目标程序的过程中，要切记保持语义 的等价性。
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1.3 编译程序构造
1.3.1 编译程序的逻辑结构 按逻辑功能不同，可将编译过程划分为五个基本阶 段，与此相对应，我们将实现整个编译过程的编译程序划 分为五个逻辑阶段（即五个逻辑子过程）。
中间形式1
C2
S.P
中间形式2