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981.
982.
A major portion of the mammalian genome is transcribed to produce large numbers of noncoding RNAs(ncRNAs).During the past decade,the discovery of small RNAs,including the microRNAs(miRNA) and small interfering RNAs(siRNA),has led to important advances in biology.The breadth of the ncRNA field of study has substantially expanded and many recent results have revealed a range of functions that can be attributed to the miRNAs and other ncRNAs.For example,H19 RNA,HOTAIR RNA,transcribed ultraconserved regions(T-UCRs),natural antisense RNA,transfer RNA and mitochondrial noncoding RNA have been suggested to play important roles in cancers and other diseases as well as in diverse cellular processes.In this review,we focus on the current status of several classes of ncRNAs associated with cancer with the emphasis on those that are not microRNAs. 相似文献
983.
This paper presents a fast pseudorandom generation algorithm, which is based on the BLAKE hash function and can pass the random
test of the NIST (National Institute of Standards and Technology) Statistical Test Suite. Through theoretical analysis and
experimental imitation, our new algorithm is proven to be more secure and efficient than G-SHA1. Simultaneously, we introduce
and discuss the BLAKE in detail. Its security shows that can be utilized to generate pseudorandom bit sequences, which the
experimental results show the BLAKE hash function has excellent pseudorandomness. Therefore, we believe the BLAKE is one of
the most potential candidate algorithms of SHA-3 program. 相似文献
984.
NECESSARY AND SUFFICIENT CONDITION FOR GLOBAL CONTROLLABILITY OF A CLASS OF AFFINE NONLINEAR SYSTEMS
Yimin SUN Shengwei MEI Qiang LU 《系统科学与复杂性》2007,20(4):492-500
In this paper, we investigate the global controllability of a class of n-dimensional affine nonlinear systems with n- 1 controls and constant control matrix. A necessary and sufficient condition for its global controllability has been obtained by using the methods recently developed. Furthermore, we generalize the above result to a class of affine nonlinear systems with a block-triangular-like structure. Finally, we will give three examples to show the applications of our results. 相似文献
985.
焦小平 《阜阳师范学院学报(自然科学版)》2000,17(4):56-58
本文介绍了在中师数学课堂教学中培养学生自学能力、减轻学生的课业负担、提高课堂教学效率方面所做的探索性尝试。 相似文献
986.
This paper gives a theoretical analysis for the algorithms to compute functional decomposition for multivariate polynomials based on differentiation and homogenization which were proposed by Ye,Dai,and Lam(1999) and were developed by Faugere,Perret(2006,2008,2009).The authors show that a degree proper functional decomposition for a set of randomly decomposable quartic homogenous polynomials can be computed using the algorithm with high probability.This solves a conjecture proposed by Ye,Dai,and Lam(1999).The authors also propose a conjecture which asserts that the decomposition for a set of polynomials can be computed from that of its homogenization and show that the conjecture is valid with high probability for quartic polynomials.Finally,the authors prove that the right decomposition factors for a set of polynomials can be computed from its right decomposition factor space. 相似文献
987.
多进出口空间混合对流传热的数值分析 总被引:1,自引:0,他引:1
采用原始变量,等间距的交错网格等方法对多进出口空间混合对流传热问题进行数值分析。通过对不同几何模型和边界条件在较宽的参数范围内进行计算,从而总结出混合对流传热的一般规律。 相似文献
988.
Alexey B. Petrovsky 《系统科学与系统工程学报(英文版)》2007,16(1):22-33
There are many practical decision problems where decision makers' preferences may be inconsistent and contradictory. In this paper, new methods for ordering and classifying multi-attribute objects by discordant collective preferences are suggested. These methods are based on the theory of multiset metric spaces. The proposed techniques are applied to ranking companies and a competitive selection of projects, which are estimated by several experts upon multiple qualitative criteria. 相似文献
989.
邱锦艳 《黔西南民族师范高等专科学校学报》2007,(1):42-43,53
阅读是掌握语言知识、打好语言基础、获取信息的重要渠道。阅读能力是大部分大学生今后工作所需的主要语言技能,在大学英语教学中要始终注重阅读能力的培养。从语言学习的规律来看,英语应用能力的提高是建立在大量的语言输入,尤其是大量阅读的基础之上的。近年来,随着考试命题要求的不断提高,考查学生阅读能力的试题比重越来越大,阅读难度有所增加。因此,如何培养和提高肇生阅读能力,显得尤为重要。 相似文献
990.
丘世钧 《华南师范大学学报(自然科学版)》1985,(1):1
松散堆积物的粒度成分及分布规律与沉积环境息息相关,于潮间带以平台地形出现的现代礁坪对其上的松散堆积物的沉积过程施于深刻的影响.本文就海南岛西北岸邻昌、大铲离岸礁和小铲近岸滩礁礁坪上的松散堆积物的粒度参数和粒度分布的若干特征,探讨它们与沉积环境的关系. 相似文献