sat作文

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1、1.袁隆平袁隆平(1930-),农学家、杂交水稻育种专家。1953年西南农学院农学系毕业。历任研究员、湖南杂交水稻研究中心主任、湖南农科院名誉院长、国家杂交水稻工程技术研究中心主任,1995年当选为中国工程院院士。 袁隆平长期从事杂交水稻育种理论研究和制种技术实践。1964年首先提出培育“不育系、保持系、恢复系”三系法利用水稻杂种优势的设想并进行科学实验。1970年,与其助手李必湖和冯克珊在海南发现一株花粉败育的雄性不育野生稻,成为突破“三系”配套的关键。 1972年育成中国第一个大面积应用的水稻雄性不育系“二九南一号A”和相应的保持系“二九南一号B”,次年育成了第一个大面积推广的强优组合“南

2、优二号”,并研究出整套制种技术。1986年提出杂交水稻育种分为“三系法品种间杂种优势利用、两系法亚种间杂种优势利用到一系法远缘杂种优势利用”的战略设想。被同行们誉为“杂交水稻之父”Yuan Longping(1930-)I saw rice plants as tall as Chinese sorghum,” said Yuan Longping of a dream he once had, “each ear of rice as big as a broom and each grain of rice as huge as a peanut. I could hide in the

3、shadow of the rice crops with a friend. Born into a poor farmers family in 1931 and a graduate from the Southwest Agriculture Institute in 1953, Yuan began his teaching career at an agriculture school in Anjiang, Hunan Province.He came up with an idea for hybridizing rice in the 1960s, when a series

4、 of natural disasters and inappropriate policies had plunged China into an unprecedented famine that caused many deaths. Since then, he has devoted himself to the research and development of a better rice breed. In 1964, he happened to find a natural hybrid rice plant that had obvious advantages ove

5、r others. Greatly encouraged, he began to study the elements of this particular type. In 1973, in cooperation with others, he was able to cultivate a type of hybrid rice species which had great advantages. It yielded 20 percent more per unit than that of common ones.The next year their research made

6、 a breakthrough in seeding. They successfully developed a set of technologies for producing indica (long-grained non-glutinous) rice, putting China in the lead worldwide in rice production. For this achievement, he was dubbed the Father of Hybrid Rice. In 1979, their technique for hybrid rice was in

7、troduced into the United States, the first case of intellectual property rights transfer in the history of new China.Key words:agriculturist father of hybrid rice2.约翰那什约翰纳什生于1928年6月13日。父亲是电子工程师与教师,第一次世界大战的老兵。纳什小时孤独内向,虽然父母对他照顾有加,但老师认为他不合群不善社交。 纳什的数学天分大约在14岁开始展现。他在普林斯顿大学读博士时刚刚二十出头,但他的一篇关于非合作博弈的博士论文和其他

8、相关文章,确立了他博弈论大师的地位。在20世纪50年代末,他已是闻名世界的科学家了。然而,正当他的事业如日中天的时候,30岁的纳什得了严重的精神分裂症。他的妻子艾利西亚麻省理工学院物理系毕业生,表现出钢铁一般的意志:她挺过了丈夫被禁闭治疗、孤立无援的日子,走过了惟一儿子同样罹患精神分裂症的震惊与哀伤漫长的半个世纪之后,她的耐心和毅力终于创下了了不起的奇迹:和她的儿子一样,纳什教授渐渐康复,并在1994年获得诺贝尔奖经济学奖。如今,纳什已经基本恢复正常,并重新开始科学研究。他现在是普林斯顿大学数学教授,但已经不再任教。学校经济学系经常会举办有关博弈论的论坛,纳什有时候会参加,但是他几乎从不发言,

9、每次都是静静地来,静静地走。 John Nash(1928-)When the young Nash had applied to graduate school at Princeton in 1948, his old Carnegie Tech professor, R.J. Duffin, wrote only one line on his letter of recommendation: This man is a genius. It was at Princeton that Nash encountered the theory of games, then recentl

10、y launched by John von Neumann and Oskar Morgenstern. However, they had only managed to solve non-cooperative games in the case of pure rivalries (i.e. zero-sum). The young Nash turned to rivalries with mutual gain. His trick was the use of best-response functions and a recent theorem that had just

11、emerged - Kakutanis fixed point-theorem. His main result, the Nash Equilibrium, was published in 1950 in the Proceedings of the National Academy of Sciences. He followed this up with a paper which introduced yet another solution concept - this time for two-person cooperative games - the Nash Bargain

12、ing Solution (NBS) in 1950. A 1951 paper attached his name to yet another side of economics - this time, the Nash Programme, reflecting his methodological call for the reduction of all cooperative games into a non-cooperative framework.His contributions to mathematics were no less remarkable. As an

13、undergraduate, he had inadvertently (and independently) proved Brouwers fixed point theorem. Later on, he went on to break one of Riemanns most perplexing mathematical conundrums. From then on, Nash provided breakthrough after breakthrough in mathematics. In 1958, on the threshold of his career, Nas

14、h got struck by paranoid schizophrenia. He lost his job at M.I.T. in 1959 (he had been tenured there in 1958 - at the age of 29) and was virtually incapicated by the disease for the next two decades or so. He roamed about Europe and America, finally, returning to Princeton where he became a sad, gho

15、stly character on the campus - the Phantom of Fine Hall as Rebecca Goldstein described him in her novel, Mind-Body Problem. The disease began to evaporate in the early 1970s and Nash began to gradually to return to his work in mathematics. However, Nash himself associated his madness with his living

16、 on an ultralogical plane, breathing air too rare for most mortals, and if being cured meant he could no longer do any original work at that level, then, Nash argued, a remission might not be worthwhile in the end. As John Dryden once put it:Great wits are sure to madness near allied, And thin partitions do their bounds divide.Key words: economist illness Nobel price winner

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