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 为了更好的帮助您理解掌握查询词或其译词在地道英语中的实际用法，我们为您准备了出自英文原文的大量英语例句，供您参考。 
It is well known that Gabor expansions generated by a lattice of Nyquist density are numerically unstable, in the sense that they do not constitute frame decompositions.


It is well known that for certain sequences {tn}n∈? the usual Lp norm ∥·∥p in the PaleyWiener space PWτp is equivalent to the discrete norm ‖f‖p,{tn}:=(∑n=∞∞f(tn)p)1/p for 1 ≤ p = >amp;lt; ∞ and ‖f‖∞,{tn}:=supn∈?f(tn for p=∞).


It is well known that amplitude modulation does not affect Fredholmness of Toeplitz operators.


It is well known that singular maps (i.e., those have only one face on a surface) play a key role in the theory of upembeddability of graphs.


Although the two electrontransfer branches in the reaction centers (RC) of purple bacteria are virtually symmetric, it is well known that only one of them is functionally active (the Abranch).

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Itis well known that this independence implicitlyassumes that a population's effective size(Ne) is equal to its census size(N).




 The measurement with given standard deviation of population σ is presented in this paper,which is proved to be more officient than Nairs one in judyement without consulting any table and with fiducial probability p as a fixed value(0 99 or 0 95)  这是已知总体标准差σ判断异常值的一种检验法。这种检验法不用查表，置信概率ｐ为固定值（０９９或０９５），本文证明了它比奈尔检验法的判断效率高。  It is well known that narrow slit may be used as acoustical element. The exact formulae of the acoustical impedance of a narrow slit and its lowfrequency approximation are available. The theory of slit is extended and a simple and practical formula is derived for the single slit. It is found that the resistancestoreactance ratio of the slit increases to larger than one when the slit width is decreased to submillimeter range, and a panel with extremely narrow slits plus a back cavity will make an absorber... It is well known that narrow slit may be used as acoustical element. The exact formulae of the acoustical impedance of a narrow slit and its lowfrequency approximation are available. The theory of slit is extended and a simple and practical formula is derived for the single slit. It is found that the resistancestoreactance ratio of the slit increases to larger than one when the slit width is decreased to submillimeter range, and a panel with extremely narrow slits plus a back cavity will make an absorber with good absorption in a wide frequency range, without any porous or fibrous material. A complete theory of the microslit absorber (MSA) is, thus, presented and its absorption characteristics are discussed. It is found that the MSA has essentially the same formulae as the microperforated absorber (MPA), except that the numerical coefficient of the resistance is smaller and the end correction for the mass reactance is larger for the MSA, resulting a performance inferior to that of MPA, ordinarily. Measures are proposed to compensate for these.  窄缝可做为声学原件，这是已知的。窄缝的声阻抗严格公式以及低频近似公式都存在。本文发展了窄缝的基本理论，求得了其声阻抗的简单实用公式。由此可见，缝宽减小至丝米级，其阻抗比将超过一，因而微缝板加后腔形成的微缝吸声体可具有良好吸声性能，而不需任何多孔性或纤维性材料。文中提出微缝吸声体的概念和严格理论，并讨论其吸声性能。微缝吸声体的公式与微穿孔吸声体的完全相似，只是其声阻系数较小而声抗过大，一般说，如参数相同，其吸声特性将比微穿孔吸声体为差。改进措施可有效地补救。  A new ornithopod dinosaur,Lanzhousaurus magnidens gen. et sp. nov.,from the Early Cretaceous of the Lanzhou Basin, Gansu Province,China,possesses the largest teeth of any herbivorous dinosaur yet discovered. The dental morphology of Lanz housaurus,in which only 14,～4 cm wide tooth families are preserved in the tooth row of the 1 m long lower jaw,augments the known morphological diversity of dinosaurs. Cladistic analysis recovers a close relationship between L. magnidens and Lurdusaurus are natus from the... A new ornithopod dinosaur,Lanzhousaurus magnidens gen. et sp. nov.,from the Early Cretaceous of the Lanzhou Basin, Gansu Province,China,possesses the largest teeth of any herbivorous dinosaur yet discovered. The dental morphology of Lanz housaurus,in which only 14,～4 cm wide tooth families are preserved in the tooth row of the 1 m long lower jaw,augments the known morphological diversity of dinosaurs. Cladistic analysis recovers a close relationship between L. magnidens and Lurdusaurus are natus from the Early Cretaceous of Africa. Together,these species represent a previously unrecognized,massively constructed quadrupedal lineage in the evolution of ornithopod dinosaurs. This discovery also implies a close connection between Eurasia and Africa during the Early Cretaceous.  巨齿兰州龙(新属、新种)是发现于中国甘肃省兰州盆地早白垩世地层中的一新鸟脚类恐龙,其牙齿是世界上已知植食性恐龙中最大的。兰州龙下颌长1m,每侧有14个齿槽,而单个牙齿宽约4cm,这是已知恐龙中的首次报道。分支系统学分析发现巨齿兰州龙与非洲早白垩世的Lurdusaurusarenatus关系密切。它们代表了鸟脚类恐龙进化中四足行走的笨重的一新支。兰州龙的发现也表明欧亚大陆与非洲在早白垩世具有较密切的联系。   << 更多相关文摘 
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