我们的结果应该投哪个期刊？ 我们近年一共发现了 3 个 比当前国内外《数理统计学》教材中普遍使用的“ Fisher z 变换”更好的初等显式 函数 。 （1） 第一个 形式 特别简单，已经被《 Transactions of Tianjin University 》录用。这是EI核心期刊。 该函数的最大误差是“Fisher z 变换”的 70.7% ，累计误差为“Fisher z 变换”的 141% 。 该 Quadratic Radical Function 很简单，对改进某重要问题的计算机算法，有很好的作用。不排除将来进入《计算机算法设计与分析》之类书籍或教材的可能性。这个是不是有点 阿Q 了 ？ （2） 第二个 形式略微复杂，已经被《 Communications in Statistics-Theory and Methods 》录用。目前是4区的SCI期刊。 该函数的最大误差是“Fisher z 变换”的 21.4% ，累计误差为“Fisher z 变换”的 8.90% 。 该 Sigmoid-like 函数首次胜过“Fisher z 变换”，不仅可以替换“Fisher z 变换”取得更好的精度，还对加深了解“Fisher z 变换”有重要的启发。 现在是 第三个 初等显式函数要投稿，不知道 投哪里 ？请您指教！ 谢谢！ 第三个函数 的最大误差约是“Fisher z 变换”的 18% ，累计误差约为“Fisher z 变换”的 4.7% 。 第三个函数的形式比第二个“应该”简单些。 除了我们的工作，Yun, Beong In 的 Approximation to the cumulative normal distribution using hyperbolic tangent based functions, Journal of the Korean Mathematical Society , 2009, 46(6): 1267-1276. 是近期的他人工作，里面有近几十年有 关工作的概述。这也是个4区的SCI期刊。 ————————— 相关背景 ————————— Sir Ronald Aylmer Fisher Photograph courtesy of Professor A W F Edwards by kind permission of Joan Fisher Box http://www.galtoninstitute.org.uk/Newsletters/GINL0306/university_of_cambridge_eugenics.htm 在《 大 英百科全书 ， Encyclopaedia Britannica 》 http://www.britannica.com/EBchecked/topic/208658/Sir-Ronald-Aylmer-Fisher Sir Ronald Aylmer Fisher, byname R.A. Fisher (born February 17, 1890, London, England—died July 29, 1962, Adelaide, Australia), British statistician and geneticist who pioneered the application of statistical procedures to the design of scientific experiments. 在《 The MacTutor History of Mathematics archive 》 http://www-history.mcs.st-andrews.ac.uk/Biographies/Fisher.html Fisher z-transform 在《苏联数学百科全书》的当前网络版 词条“Correlation (in statistics)” http://www.encyclopediaofmath.org/index.php/Correlation_(in_statistics) If one usually uses the Fisher z-transform , with replaced byz according to the formula Even at relatively small values the distribution of is a good approximation to the normal distribution with mathematical expectation and variance . On this basis one can now define approximate confidence intervals for the true correlation coefficient . For the distribution of the sample correlation ratio and for tests of the linearity hypothesis for the regression, see . References H. Cramér, "Mathematical methods of statistics" , Princeton Univ. Press (1946) B.L. van der Waerden, "Mathematische Statistik" , Springer (1957) M.G. Kendall, A. Stuart, "The advanced theory of statistics" , 2. Inference andrelationship , Griffin (1979) S.A. Aivazyan, "Statistical research on dependence" , Moscow (1968) (In Russian) 相关链接： 《胜过 Fisher z 变换！（1）》 http://bbs.sciencenet.cn/home.php?mod=spaceuid=107667do=blogid=603297 《胜过 Fisher z 变换！（2）》 http://blog.sciencenet.cn/home.php?mod=spaceuid=107667do=blogid=657534
Microprojectile-mediated transformation of rice was carried out according to the procedure described in ref. 25 . Calli were derived from the hypocotyls of germinating mature seeds of the cultivar TP309 ( Oryza sativa , subsp. Japonica ). Calli with a diameter of 24 mm were selected and placed on an N6 medium (Sigma) supplemented with 0.3 M mannitol and 0.3 M sorbitol for about 20 h before bombardment. Bombardment was carried out with the Biolistic PDC-1000/He instrument (Bio-Rad). Fifty microliters of gold particles (60 mgml 1 at 1:1 ratio of 1.0 and 1.53.0 m diameter gold particle) were coated with effector DNA, target DNA, and selection marker DNA in a ratio of 3:3:1 (wt/wt) and accelerated with a helium pressure of 1,100 psi. After a 2-day incubation, calli were transferred to N6 selection media containing 35 mgl 1 hygromycin B and allowed to grow in dark at 26C for 45 days. Calli resistant to hygromycin B were transferred to regeneration media to generate plantlets as described in ref. 25 . After shoots had reached a height of 13 cm, the plantlets were transferred to rooting media (MS plus 0.05 mgl 1 -naphthaleneactic acid, Sigma). After 2 weeks, the plantlets were transferred to soil and grown in a greenhouse to maturity.
Abstract. Besides Einsteins two fundamental postulates, additional assumptions are made in various derivations of the Lorentz transformation (LT). Two or three so-called exact derivations of the LT have been highly abstract and abstruse. Thus, the validity of the derivation of the LT has been questioned. Here, we present a rigorous derivation of the LT, the approach of which differs from that typically employed. Our derivation is only based on the constancy of the speed of light and two thought experiments. No additional assumptions are needed because the constancy of the speed of light is used to prove the necessary assumptions. A rigorous derivation of the Lorentz transformatio
第2代转基因技术这个词来自于一篇网络文章.这里面的所谓的第2代基本观点应该是这篇文章的 All-native DNA transformation: a new approach to plant genetic engineering All-native DNA transformation ,作者 Caius M. Rommens,单位:J.R. Simplot Company,Simplot Plant Sciences.单位我不熟悉,但肯定是公司 .............................................................. 还有这篇 The intragenic approach as a new extension to traditional plant breeding intragenic 这篇文章的第一作者为Caius M. Rommens 综合两篇文章的信息,可以这样概括:至少有一个美国公司在开发第2代转基因技术.一旦这做的非常成熟了,再要反对转基因该怎么反?第2代反不了第1代还是可以反的. ........................................................ 关于转基因,现在有人反转基因反得热闹.但转基因好象是能够发展到你想反都没有理由去反对的地步.关于转基因产品的推广,既然有争议,可以放缓,但对转基因技术的研究则不可掉以轻心.
标签: transformation
