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“Greatest lake period” and its palaeo-environment on the Tibetan Plateau 被引量:7
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作者 LI Bing-yuan, ZHU Li-ping (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第1期34-42,共9页
The “greatest lake period” means that the lakes are in the stage of their maximum areas. As the paleo lake shorelines are widely distributed in the lake basins on the Tibetan Plateau, the lake areas during the “gre... The “greatest lake period” means that the lakes are in the stage of their maximum areas. As the paleo lake shorelines are widely distributed in the lake basins on the Tibetan Plateau, the lake areas during the “greatest lake period” may be inferred by the last highest lake shorelines. They are several, even tens times larger than that at present. According to the analyses of tens of lakes on the Plateau, most dating data fell into the range of 40-25 ka BP, some lasted to 20 ka BP. It was corresponded to the stage 3 of marine isotope and interstitial of last glaciation. The occurrence of maximum areas of lakes marked the very humid period on the Plateau and was also related to the stronger summer monsoon during that period. 展开更多
关键词 Tibetan Plateau greatest lake period highest lake levels interstitial of last glaciation paleo-monsoon
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A CLASS OF NATURALLY ORDERED ABUNDANT SEMIGROUPS WITH A GREATESTIDEMPOTENT
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作者 曾祥金 景奉杰 《Acta Mathematica Scientia》 SCIE CSCD 1997年第2期198-204,共7页
On the base of the construction of abundant semigroups with a normal medial idempotent [14], in this paper we consider a class of naturally ordered abundant semigroups which satisfies the regularity condition and cont... On the base of the construction of abundant semigroups with a normal medial idempotent [14], in this paper we consider a class of naturally ordered abundant semigroups which satisfies the regularity condition and contains a greatest idempotent. Furthermore, we give a completely description of the overall structure of such ordered semigroups via the algebraic structure of them, which generalizes known result obtained by Blyth and McFadden[3]. 展开更多
关键词 abundant semigroups natural order greatest idempotents
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A Note on Determine the Greatest Common Subfamily of Two NFSRs by Grbner Basis
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作者 WANG Zhongxiao QI Wenfeng TIAN Tian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第5期1231-1242,共12页
For nonlinear feedback shift registers (NFSRs), their greatest common subfamily may be not unique. Given two NFSRs, the authors only consider the case that their greatest common subfamily exists and is unique. If th... For nonlinear feedback shift registers (NFSRs), their greatest common subfamily may be not unique. Given two NFSRs, the authors only consider the case that their greatest common subfamily exists and is unique. If the greatest common subfamily is exactly the set of all sequences which can be generated by both of them, the authors can determine it by Grobner basis theory. Otherwise, the authors can determine it under some conditions and partly solve the problem. 展开更多
关键词 greatest common subfamily Grobner basis nonlinear feedback shift register stream cipher
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High Unemployment: Greatest ChallengeTo China in the New Millennium
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作者 Hu Angang 《China Population Today》 2000年第4期2-5,共4页
关键词 High Unemployment greatest ChallengeTo China in the New Millennium rate than
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Unemployment──The Greatest Challenge to China in the Next Century
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作者 HuAngang 《China's Foreign Trade》 1999年第11期18-19,共2页
关键词 The greatest Challenge to China in the Next Century UNEMPLOYMENT
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Dickens The Greatest Critical Realist
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《零陵学院学报》 1995年第Z1期65-68,共4页
Charles John Huffum Dickens(1812 k1870) was born in a poor petty-bourgeois family. His father was a clerk in the Navy Pay Office. When he was twelve, his father was heavily in debt and was
关键词 口口 In 口门 Dickens The greatest Critical Realist
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Guardian Correspondent:China Is the “Greatest Place for Foreign Journalists”
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作者 FU QI 《The Journal of Human Rights》 2008年第3期7-9,共3页
"I have worked in ten countries as a reporter and been posted in two, China and Japan," said Jonathan Watts, correspondent of The Guardian in Beijing. "I think China is the greatest place for journalists."
关键词 Guardian Correspondent greatest Place for Foreign Journalists
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China's Greatest Contribution to the World Lies in Safeguarding Democracy and Wellbeing for One-Fifth of Humanity
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作者 SONG YUEHONG researcher of the Institute of Modern China Studies under the Chinese Academy of Social Sciences 《The Journal of Human Rights》 2010年第2期18-23,共6页
China has a population that is one-fifth of humanity. Most of its people live in rural areas. This country has been built and developed on the ruins of semi-colonialism and semi-feudalism and on a foundation of "pove... China has a population that is one-fifth of humanity. Most of its people live in rural areas. This country has been built and developed on the ruins of semi-colonialism and semi-feudalism and on a foundation of "poverty and blankness." The founding of New China created the political condition for the advancement of people's democracy. Since the adoption of reform and open policies, or gaige kaifang, China has gradually found an effective way, suited for Chinese conditions, 展开更多
关键词 China’s greatest Contribution to the World Lies in Safeguarding Democracy and Wellbeing for One-Fifth of Humanity World
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The Greatest Liar
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《大学英语》 2000年第11期18-,共1页
关键词 The greatest Liar
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Fermat and Pythagoras Divisors for a New Explicit Proof of Fermat’s Theorem:a4 + b4 = c4. Part I
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作者 Prosper Kouadio Kimou François Emmanuel Tanoé Kouassi Vincent Kouakou 《Advances in Pure Mathematics》 2024年第4期303-319,共17页
In this paper we prove in a new way, the well known result, that Fermat’s equation a<sup>4</sup> + b<sup>4</sup> = c<sup>4</sup>, is not solvable in ℕ , when abc≠0 . To show this ... In this paper we prove in a new way, the well known result, that Fermat’s equation a<sup>4</sup> + b<sup>4</sup> = c<sup>4</sup>, is not solvable in ℕ , when abc≠0 . To show this result, it suffices to prove that: ( F 0 ): a 1 4 + ( 2 s b 1 ) 4 = c 1 4 , is not solvable in ℕ , (where a 1 , b 1 , c 1 ∈2ℕ+1 , pairwise primes, with necessarly 2≤s∈ℕ ). The key idea of our proof is to show that if (F<sub>0</sub>) holds, then there exist α 2 , β 2 , γ 2 ∈2ℕ+1 , such that ( F 1 ): α 2 4 + ( 2 s−1 β 2 ) 4 = γ 2 4 , holds too. From where, one conclude that it is not possible, because if we choose the quantity 2 ≤ s, as minimal in value among all the solutions of ( F 0 ) , then ( α 2 ,2 s−1 β 2 , γ 2 ) is also a solution of Fermat’s type, but with 2≤s−1<s , witch is absurd. To reach such a result, we suppose first that (F<sub>0</sub>) is solvable in ( a 1 ,2 s b 1 , c 1 ) , s ≥ 2 like above;afterwards, proceeding with “Pythagorician divisors”, we creat the notions of “Fermat’s b-absolute divisors”: ( d b , d ′ b ) which it uses hereafter. Then to conclude our proof, we establish the following main theorem: there is an equivalence between (i) and (ii): (i) (F<sub>0</sub>): a 1 4 + ( 2 s b 1 ) 4 = c 1 4 , is solvable in ℕ , with 2≤s∈ℕ , ( a 1 , b 1 , c 1 )∈ ( 2ℕ+1 ) 3 , coprime in pairs. (ii) ∃( a 1 , b 1 , c 1 )∈ ( 2ℕ+1 ) 3 , coprime in pairs, for wich: ∃( b ′ 2 , b 2 , b ″ 2 )∈ ( 2ℕ+1 ) 3 coprime in pairs, and 2≤s∈ℕ , checking b 1 = b ′ 2 b 2 b ″ 2 , and such that for notations: S=s−λ( s−1 ) , with λ∈{ 0,1 } defined by c 1 − a 1 2 ≡λ( mod2 ) , d b =gcd( 2 s b 1 , c 1 − a 1 )= 2 S b 2 and d ′ b = 2 s−S b ′ 2 = 2 s B 2 d b , where ( 2 s B 2 ) 2 =gcd( b 1 2 , c 1 2 − a 1 2 ) , the following system is checked: { c 1 − a 1 = d b 4 2 2+λ = 2 2−λ ( 2 S−1 b 2 ) 4 c 1 + a 1 = 2 1+λ d ′ b 4 = 2 1+λ ( 2 s−S b ′ 2 ) 4 c 1 2 + a 1 2 =2 b ″ 2 4;and this system implies: ( b 1−λ,2 4 ) 2 + ( 2 4s−3 b λ,2 4 ) 2 = ( b ″ 2 2 ) 2;where: ( b 1−λ,2 , b λ,2 , b ″ 2 )={ ( b ′ 2 , b 2 , b ″ 2 )  if λ=0 ( b 2 , b ′ 2 , b ″ 2 )  if λ=1;From where, it is quite easy to conclude, following the method explained above, and which thus closes, part I, of this article. . 展开更多
关键词 Factorisation in greatest Common Divisor Pythagoras Equation Pythagorician Triplets Fermat's Equations Pythagorician Divisors Fermat's Divisors Diophantine Equations of Degree 2 4-Integral Closure of in
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多通道奇异频率信号的稳相合成研究
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作者 陈昌锐 李超 谢翔宇 《压电与声光》 CAS 北大核心 2024年第3期404-408,共5页
为了解决多通道奇异频率间相位差稳定的难题,理论上分析了锁相环稳相原理,提出了一种多通道奇异频率的稳相算法。该算法通过求解奇异频率间的最大公约数,联动输出频率的同时可满足稳相合成的条件。电路实物加入适当的环路阶型设计,当输... 为了解决多通道奇异频率间相位差稳定的难题,理论上分析了锁相环稳相原理,提出了一种多通道奇异频率的稳相算法。该算法通过求解奇异频率间的最大公约数,联动输出频率的同时可满足稳相合成的条件。电路实物加入适当的环路阶型设计,当输出频率在S波段时,相位差稳定性≤4°,满足使用需求,同时很好地验证了该算法的可行性和灵活性。 展开更多
关键词 异频 稳相 锁相环 最大公约数
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围长为8的较大列重准循环低密度奇偶校验码的行重普适代数构造
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作者 张国华 秦煜 +1 位作者 娄蒙娟 方毅 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第7期3019-3025,共7页
适合于任意行重(即行重普适(RWU))的无小环准循环(QC)低密度奇偶校验(LDPC)短码,对于LDPC码的理论研究和工程应用具有重要意义。具有行重普适特性且消除4环6环的现有构造方法,只能针对列重为3和4的情况提供QC-LDPC短码。该文在最大公约... 适合于任意行重(即行重普适(RWU))的无小环准循环(QC)低密度奇偶校验(LDPC)短码,对于LDPC码的理论研究和工程应用具有重要意义。具有行重普适特性且消除4环6环的现有构造方法,只能针对列重为3和4的情况提供QC-LDPC短码。该文在最大公约数(GCD)框架的基础上,对于列重为5和6的情况,提出了3种具有行重普适特性且消除4环6环的构造方法。与现有的行重普适方法相比,新方法提供的码长从目前的与行重呈4次方关系锐减至与行重呈3次方关系,因而可以为QC-LDPC码的复合构造和高级优化等需要较大列重基础码的场合提供行重普适的无4环无6环短码。此外,与基于计算机搜索的对称结构QC-LDPC码相比,新码不仅无需搜索、描述复杂度更低,而且具有更好的译码性能。 展开更多
关键词 低密度奇偶校验码 准循环 围长 最大公约数
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The Greatest Prime Factor of the Integers in a Short Interval (Ⅳ) 被引量:1
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作者 Jia Chaohua Institute of Mathematics Academia Sinica Beijing, 100080 China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1996年第4期433-445,共13页
Let P(x) denote the greatest prime factor of ∏<sub>x【n≤x+x<sup>1/2</sup></sub>n. In this paper, we shall prove that P(x)】x<sup>0.728</sup>holds true for sufficiently large x.
关键词 MATH In The greatest Prime Factor of the Integers in a Short Interval
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THE GREATEST PRIME FACTOR OF THE INTEGERS IN A SHORT INTERVAL(Ⅰ)
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作者 贾朝华 《Chinese Science Bulletin》 SCIE EI CAS 1987年第7期500-501,共2页
Let P(x, y) denote the greatest prime factor of multiply from x<n≤x+y n. Ramachandra proved that P(x, x1/2)>x15/26 and P(x,x1/2)>x5/8(see J. London Math. Soc., 1(1969), 303—306 and J. Indian Math. Soc.... Let P(x, y) denote the greatest prime factor of multiply from x<n≤x+y n. Ramachandra proved that P(x, x1/2)>x15/26 and P(x,x1/2)>x5/8(see J. London Math. Soc., 1(1969), 303—306 and J. Indian Math. Soc., 34(1970), 39—48). In 1981, Graham improved the exponent to 0.662(J. London Math. Soc., 24(1981), 427—440). 展开更多
关键词 EXPONENT GRAHAM multiply Indian LONDON greatest Vaughan letter HEATH
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Peace Is the Greatest Trait of China's Development
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作者 Zhang Weiwei 《Qiu Shi》 2019年第2期74-83,共10页
In the short period of 70 years between 1949 and 2019, socialist China has lifted itself, through unwavering efforts, from economic and cultural destitution to become the worlds second largest economy, largest manufac... In the short period of 70 years between 1949 and 2019, socialist China has lifted itself, through unwavering efforts, from economic and cultural destitution to become the worlds second largest economy, largest manufacturing nation, largest trader of goods, second largest consumer of commodities, and second largest recipient of foreign investment. It has held the world5s largest foreign exchange reserves and contributed about 30% of global economic growth for many years running, while its GDP accounts for 15.2% of the global total. 展开更多
关键词 greatest TRAIT China's DEVELOPMENT 70 YEARS
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JERRY RICE Football's greatest player dishes on Super Bowls and career highs
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作者 ANDREW CHIN 《城市漫步(GBA版)》 2014年第11期16-16,共1页
How did you feel about being chosen as football's greatest player?You would never hear me say that,so I feel honored to be selected.I think it had to do with my work ethic and approach to the game.I always wanted ... How did you feel about being chosen as football's greatest player?You would never hear me say that,so I feel honored to be selected.I think it had to do with my work ethic and approach to the game.I always wanted to perform at my best.If I had just 11 catches for more than 100 yards,I wanted to come back next week and have a better game. 展开更多
关键词 PLAYER greatest WANTED
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WORLD CUP CHINA? Plans afoot to host planet's greatest sporting show
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作者 IAN WALKER 《城市漫步(GBA版)》 2015年第4期92-92,共1页
Former England international goalkeeper,Ian Walker played for Tottenham Hotspur,Leicester City and Bolton Wanderers.In 2012 he moved to China to become goalkeeper coach of Shanghai Shenhua,before crossing the city div... Former England international goalkeeper,Ian Walker played for Tottenham Hotspur,Leicester City and Bolton Wanderers.In 2012 he moved to China to become goalkeeper coach of Shanghai Shenhua,before crossing the city divide to join Shanghai SIPG in 2014.Follow him on Twitter and Weibo@lanWalksl. 展开更多
关键词 PLANET Bolton greatest
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JERRY RICE Football's greatest ptayer touches down in Shanghai
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作者 ANDREW CHIN 《城市漫步(上海版、英文)》 2014年第11期20-21,共2页
Last year,legendary quarterback Joe Montana came for a China tour.In 2014,his longtime卩artner Jerry Rice has made the trip out East.Lauded by the NFL Network as footballs Greatest Player Ever,the wide receiver holds ... Last year,legendary quarterback Joe Montana came for a China tour.In 2014,his longtime卩artner Jerry Rice has made the trip out East.Lauded by the NFL Network as footballs Greatest Player Ever,the wide receiver holds a ridiculous array of the sports records:most touchdowns,most receptions completed and most yards caught.We caught up with Rice and the 13-time Pro Bowler dished on his career,his Super Bowl predictions and his dancing prowess. 展开更多
关键词 holds Montana greatest
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WORLD CUP CHINA?Plans afoot to host pSnefs greatest sporting show
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作者 IAN WALKER 《城市漫步(上海版、英文)》 2015年第4期120-120,共1页
Former England international goalkeeper,lan Walker played for Tottenham Hotspur,Leicester City and Bolton Wanderers.In 2012 he moved to China to become goalkeeper coach of Shanghai Shenhua,before crossing the city div... Former England international goalkeeper,lan Walker played for Tottenham Hotspur,Leicester City and Bolton Wanderers.In 2012 he moved to China to become goalkeeper coach of Shanghai Shenhua,before crossing the city divide to join Shanghai SIPG in 2014.Follow him on Twitter and Weibo@lanWalks1. 展开更多
关键词 Bolton greatest ENGLAND
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The Greatest?
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《英语沙龙(高中)》 2011年第5期36-37,共2页
斯托克城足球俱乐部(Stoke City Football Club),是位于英格兰特伦特河畔斯托克的足球俱乐部,也是足球联盟的创始成员。该俱乐部成立于1863年,被视为仅次于诺茨郡为世界上第二古老的足球联赛俱乐部。现时在英格兰冠军联赛参加比赛,主... 斯托克城足球俱乐部(Stoke City Football Club),是位于英格兰特伦特河畔斯托克的足球俱乐部,也是足球联盟的创始成员。该俱乐部成立于1863年,被视为仅次于诺茨郡为世界上第二古老的足球联赛俱乐部。现时在英格兰冠军联赛参加比赛,主场为不列颠尼亚球场。 展开更多
关键词 《The greatest?》 英语教学 教学方法 阅读
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