新概念英語文章及譯文

　　《新概念英語》自出版以來受到了英語學習者的熱烈歡迎。下面是小編帶來的，歡迎閱讀!

　　Statistics

　　統計學

　　There were two widely divergent influences on the early development of statistical methods. Statistics had a mother who was dedicated to keeping orderly records of governmental units ***states and statistics come from the same Latin root status*** and a gentlemanly gambling father who relied on mathematics to increase his skill at playing the odds in games of chance. The influence of the mother on the offspring, statistics, is represented by counting, measuring, describing, tabulating, ordering, and the taking of censuses-all of which led to modern descriptive statistics. From the influence of the father came modern inferential statistics, which is based squarelyon theories of probability.

　　統計方法的早期發展受到兩種截然不同的影響。統計學有一個“母親”，她致力於井井有條地記錄政府機構的檔案***國家和統計學這兩個詞源於同一個拉丁語詞根，status***，還有一個有紳士般的賭博“父親”，他依靠數學來提高賭技，以便在機率的遊戲中取勝。“母親”對其子女統計學的影響表現在計數、測量、描述、製表、歸類和人口普查。所有這些導致了現代描述統計學的誕生。由於“父親”的影響則產生了完全基於概率論原理的現代推理統計學。

　　Descriptive statistics involves tabulating, depicting and describing collections of data. These data may bequantitative such as measures of height, intelligence or grade level -- variables that are characterized by an underlying continuum -- or the data may represent qualitative variables, such as sex, college major or personality type. Large masses of data must generally undergo a process of summarization or reduction before they are comprehensible. Descriptive statistics is a tool for describing or summarizing or reducing to comprehensible form the properties of an otherwise unwieldy mass of data.

　　描述統計學涉及對所收集資料的製表、製圖和描述。這些資料可以是數量性的資料，如高度、智商、或者是層級性的資料——具有連續性的變數——或資料也可以代表性質變數，如性別、大學專業或性格型別等等。數量龐大的資料通常必須經過概括或刪減的程式才能為人所理解。描述統計學就是這樣一個工具，它對極其龐雜的資料進行描述、概括或刪減，使其變成能為人理解的東西。

　　Inferential statistics is a formalized body of methods for solving another class of problems that present great difficulties for the unaided human mind. This general class of problems characteristically involve attempts to make predictions using a sample of observations. For example, a school superintendent wishes to determine the proportion of children in a large school system who come to school without breakfast, have been vaccinated for flu, or whatever. Having a little knowledge of statistics, the superintendent would know that it is unnecessary and inefficient to question each child: the proportion for the entire district could be estimated fairly accurately from a sample of as few as 100 children. Thus, the purpose of inferential statistics is to predict or estimate characteristics of a population from a knowledge of the characteristics of only a sample of the population.

　　推理統計學是一套已定形了的方法體系，它解決的是光憑人腦極難解決的另一類問題。這類問題的顯著特點是試圖通過取樣調查來作出預測。例如，有一位教育督察想知道在一個龐大的學校系統中，不吃早飯就上學的學生、已經做過防感冒免疫的學生，或其它任何型別的學生佔多大比例。若具備一些統計學的知識，這位督察應明白，詢問每個孩子是沒有必要而且沒有效率的，只要用100個孩子為樣本，他就可以相當精確地得出這些孩子佔整個學區的比例了。因此，推理統計學的目的就是通過了解一個群體中一些樣本的特性，從而對整個群體的特性進行推測和估算。

　　Coal-fired power plants

　　火力發電廠

　　The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap,readily available fuel with which to generate large amounts of electric power. Coal seemed to fit the bill, and it fueled the earliest power stations ***which were set up at the end of the nineteenth century by Edison himself***. As more power plants were constructed throughout the country, the reliance on coal increased. Since the First World War, coal-fired power plants have accounted for about half of the electricity produced in the United States each year.

　　托馬斯·愛迪生1879年發明的白熾燈導致對便宜、易得、可生產大量電能的燃料的需求。煤似乎符合這個要求，併成為第一批電廠的燃料***正是愛迪生本人在19世紀末建造了第一批電廠***。全國到處興建電廠時，對煤的依賴加深了。自第一次世界大戰以來，美國每年約有一半的電力是以煤為燃料的電廠提供的。

　　In 1986 such plants had a combined generating capacity of 289, 000 megawatts and consumed 83 percent of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty in the future growth of nuclear power and in the supply of oil and natural gas, coal-fired power plants could well provide up to 70 percent of the electric power in the United States by the end of the century.

　　1986年這些電廠的總髮電能力達到28,900千瓦並且消耗了當年全國開採的九億噸煤的83%。考慮到核能發展以及石油、天然氣供應中的不確定因素，到本世紀末，火力發電廠仍可能為美國提供多達70%的電力。

　　Yet, in spite of the fact that coal has long been a source of electricity and may remain one for many years ***coal represents about 80 percent of United States fossil-fuel reserves***, it has actually never been the most desirablefossil fuel for power plants. Coal contains less energy per unit of weight than natural gas or oil; it is difficult to transport, and it is associated with a host of environmental issues, among them acid rain. Since the late 1960's problems of emission control and waste disposal have sharply reduced the appeal of coal-fired power plants. The cost of ameliorating these environmental problems along with the rising cost of building a facility as large and complex as a coal-fired power plant, have also made such plants less attractive from a purely economic perspective.

　　然而，儘管煤長期以來一直是電力的原料之一併且可能會繼續如此***煤佔美國化石燃料儲量的80%***，它卻不是電廠的理想燃料。煤的單位能量含量低於石油和天然氣，而且會導致包括酸雨在內的一系列環境問題。從1960年以來，排放控制和垃圾處理的問題極大地削弱了燃煤電廠的魅力。由於減輕這些環境問題需要大量資金，而且建造龐大複雜的燃煤電廠的費用不斷上漲，也使得這些電廠從經濟角度上不具備吸引力。

　　Changes in the technological base of coal-fired power plants could restore their attractiveness, however. Whereas some of these changes are evolutionary and are intended mainly to increase the productivity of existing plants, completely new technologies for burning coal cleanly are also being developed.

　　改變火力發電廠的基礎技術卻可能恢復它們的吸引力。雖然某些技術改進是漸進的，其目的只是提高現有電廠的生產率，但人們正在開發全新的清潔燃煤的技術。

　　Obtaining Fresh water from icebergs

　　從冰山中獲取淡水

　　The concept of obtaining fresh water from icebergs that are towed to populated areas and arid regions of the world was once treated as a joke more appropriate to cartoons than real life. But now it is being considered quite seriously by many nations, especially since scientists have warned that the human race will outgrow its fresh water supply faster than it runs out of food.

　　把冰山拖到世界上人口稠密的地區和乾旱地帶，再從中獲取淡水，這個想法曾一度被認為是一個笑話，更適合於卡通畫，而非現實生活。然而現在，許多國家正相當認真地考慮這件事情，特別是在科學家們發出警告之後。科學家們認為人類將在耗盡糧食之前首先耗盡淡水資源。

　　Glaciers are a possible source of fresh water that has been overlooked until recently. Three-quarters of the Earth's fresh water supply is still tied up in glacial ice, a reservoir of untapped fresh water so immense that it could sustain all the rivers of the world for 1,000 years. Floating on the oceans every year are 7,659 trillionmetric tons of ice encased in 10000 icebergs that break away from the polar ice caps, more than ninety percent of them from Antarctica. Huge glaciers that stretch over the shallow continental shelf give birth to icebergs throughout the year.

　　冰川是一個直到最近以前一直被忽視的可能的淡水源。全球四分之三的淡水還鎖在冰川的冰塊中。冰川就是一個蓄水池，其中未開發的淡水量是如此巨大，足夠支援全世界的江河1000年。每年有7,659萬億公噸冰漂流在海洋中。它們包含在10,000座從極地冰帽中斷裂出來的冰山中。這些冰山的90%以上來自南極。一年四季裡，覆蓋在淺層大陸架上的巨大冰川生成了眾多冰山。

　　Icebergs are not like sea ice, which is formed when the sea itself freezes, rather, they are formed entirely on land, breaking off when glaciers spread over the sea. As they drift away from the polar region, icebergs sometimes move mysteriously in a direction opposite to the wind, pulled by subsurface currents. Because they melt more slowly than smaller pieces of ice, icebergs have been known to drift as far north as 35 degrees south of the equator in the Atlantic Ocean. To corral them and steer them to parts of the world where they are needed would not be too difficult.The difficulty arises in other technical matters, such as the prevention of rapid melting in warmer climates and the funneling of fresh water to shore in great volume. But even if the icebergs lost half of their volume in towing, the water they could provide would be far cheaper than that produced by desalinization, or removing salt from water.

　　冰山和海水的冰不同，後者是海水自身結冰形成的，而冰山則完全是在陸地上形成的。當冰川伸展到海水中時，冰山就斷裂下來。當漂離極地地區時，冰山有時會在底層洋流的推動下頗為神祕地逆風移動。由於冰山比小塊的冰融化要慢，因此有的冰山在大西洋中向北飄到了赤道以南35°的地方。把冰山蓄攔起來並拖到世界上需要它們的地方將不會太困難。有困難的是其它的技術事宜。比如，如何防止冰山在較暖的氣候中迅速融化以及如何把大量的淡水收集到岸上去。但是，即便在拖的過程中冰山失去了一半體積，這樣做也遠比從海水中脫鹽取得淡水便宜。