不定方程mx+2y+z=n(m≥3,n≥m+3)的正整数解数     

郭育红 《河西学院学报》2008,24(5)

给出了不定方程mx+2y+z=n(m≥3,n≥m+3)的正整数解以及非负整数解的个数的计算公式.同时也给出了将正整数n拆分成若干个1,2和m的拆分数的表达式.进一步给出了x1+2x2+3x3+4x4=n的正整数解的个数以及关于一般情形下的不定方程的正整数解的个数的递推关系.  相似文献   

2012—2014年F5000农业科学类论文来源及作者的文献计量学分析     

马秋明  窦春蕊  温晓平 《中国科技期刊研究》2016,27(8):818-824

【目的】对2012—2014年F5000中农业科学类论文的来源及作者进行文献计量学分析。【方法】筛选2012—2014年入选F5000的农业科学类论文,通过中国知网对其相关信息进行完善,利用EXCEL2007对论文的来源及作者信息进行统计与分析。【结果】共选出829篇论文,来自188家单位,其中中国科学院、中国农业科学院等23家高产单位共产出530篇。该类论文主要发表于少数知名度较高的中国精品科技期刊;北京和江苏产出的论文篇数远大于其他省区。论文的合著率为97.47％,合作度为4.999,20～30岁的硕士、博士作者是其核心作者群体。【结论】明确了2012—2014年F5000中农业科学类论文的来源和作者概况,为农业科技期刊编辑同仁组约高水平研究论文提供了方向。  相似文献   

各代状元在官场的发展空间——历代状元遭际考索之二     

周腊生 《宁波职业技术学院学报》2007,11(1):80-82

各代状元在官场的发展空间是很不相同的:状元宰相比例最高的是宋,最低的是唐;状元高官比例最高的是宋,最低的是五代;状元被淹没比例最高的是五代,最低的是清。综之,宋代状元在官场的发展空间最为广阔。  相似文献   

柳永词与他的从政之路     

李江峰 《山东教育学院学报》2005,20(5):34-36

柳永具有典型的两面性，他既是才华横溢的风流词客，又是苦游于宦海的颠簸士子。他的词创作和从政之路之间又有着千丝万缕的联系，可以说，《乐章集》中部分词就是其从政之路的写照。本文从柳永词作与其从政之路联系的角度上，论述了柳永在“狂荡”背后那不为人所熟悉的一面：积极于事功。  相似文献   

Relationships among computational performance,pictorial representation,symbolic representation and number sense of sixth‐grade students in Taiwan     

Der‐Ching Yang 《Educational studies》2004,30(4):373-389

Twenty classes in ten schools with 627 sixth‐grade students in five cities in Taiwan participated in this study. The research provides information on the performance differences among written computation, pictorial representation, symbolic representation and number sense. The results of One‐way ANOVA analysis indicate that significant difference was found among WCT, PRT, SRT and NST tests, with F=536.327, p=0.000. The a posteriori comparisons show for each pair (WCT vs PRT, WCT vs SRT, WCT vs NST, PRT vs SRT and SRT vs NST) significant difference at the 0.001 level (p=0.000), except for the pair comparison between PRT and NST. This implies that these Taiwanese students were highly skilled in written computation but their written skills were not equally transferred to use of non‐computational paths that depended on symbolic representation, pictorial representation and number sense to solve similar problems.  相似文献   

Number sense and the calculating child: Measure,multiplicity and mathematical monsters     

Elizabeth de Freitas 《Discourse: Studies in the Cultural Politics of Education》2016,37(5):650-661

ABSTRACT

Children and animals of all kinds are said to develop some degree of number sense. The search for ‘number neurons’ and neural correlates of computational thinking aims to identify biological primitives to explain the emergence of number sense. This work typically looks for the sources of number sense in organisms, but one might extend this search and study the possibility of a calculating matter more generally. Such a speculative project explores the implications of the non-human turn within the posthumanities. In this paper, I draw primarily on the work of Vicky Kirby and Gilles Deleuze in order to focus on becoming-monster through calculation. I show how calculation, as a machinic and empirical act that both serves and troubles images of mathematical truth, has always played a unique role in the production of mathematical monsters. I then discuss calculating children who participate in abacus clubs and annual abacus competitions, calculating at inhuman rates with imaginary abacuses. I argue that a new materialist philosophy of immanence demands a radically new approach to number sense.  相似文献   

网络状态方程研究     

张雪平 《宜宾学院学报》2005,5(6):71-76

状态变量法分析电路网络的动态过程，关键是网络状态方程的求解。本根据电路特点和计算误差的要求，介绍了网络状态方程的时域解法、频域解法、数值解法和精细积分解法。结合具体算例综合比较几种解法的特点。  相似文献   

谈俄汉民族特殊的文化现象--数字文化     

曹阳 《鞍山师范学院学报》2006,8(1):81-83

了解不同国家与民族之间的差异,以其文化现象为切入点也不失为一条捷径,文化现象是多方面的,本文试从特殊的文化现象-数字文化为突破口,对俄汉两民族独特的数字文化进行分析和比较。  相似文献   

柽柳属植物的染色体数目     

翟诗虹  李懋学 《中国科学院研究生院学报》1986,24(4):273-274

The chromosome number of thirteen species of Tamarix L. in China is re- ported in this paper.  All of them have the same number (2n=24) and most of them are reported for the first time except T. hispida, whose chromosome number is the same as previously reported.  相似文献   

Examining the reciprocal relations of mathematics anxiety to quantitative reasoning and number knowledge in Chinese children     

《Contemporary educational psychology》2020

This study aimed to examine the longitudinal relations of mathematics anxiety to quantitative reasoning and number knowledge in Chinese children. Three hundred and sixteen 6-year-old Chinese children in Hong Kong participated in two waves of assessments, eight months apart. Cross-lagged panel analyses showed that prior quantitative reasoning and number knowledge predicted lower mathematics anxiety, even after the effects of gender, mothers’ educational levels, and general anxiety were taken into account. However, earlier mathematics anxiety did not predict later quantitative reasoning and number knowledge. Our findings were consistent with the Deficit Theory, which postulates that mathematics anxiety comes from poor mathematical competence but not vice versa. We also found a reciprocal association between quantitative reasoning and number knowledge, in which initial quantitative reasoning had a stronger prediction on later number knowledge. Taken together with previous research, this result highlights the importance of quantitative reasoning in children’s mathematics learning and its role in mathematics education.  相似文献