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11.
魏莹 《武汉职业技术学院学报》2013,12(2):71-73
针对学生对矩阵乘法难以理解的问题,从实例出发引入矩阵乘法的定义,利用数学软件验证其正确性,用实例展示其应用价值。在矩阵教学中融于数学建模思想,通过实际——理论一实际的过程,帮助学生消除学习中的疑惑,突破难点。 相似文献
12.
科学知识体系的结构与演化规律 总被引：1，自引：0，他引：1
陈洪敏 《临沂师范学院学报》2003,25(2):51-54
科学知识体系是由事实前提、基本观点、特有概念、主导规律、无知识和典型应用等六要素形成的统一结构。它具有社会性、开放性、进化性、结构性和推理性等特征，并遵循建构原理、结构原理和，临原理以及增殖定律、发育重演律和投入产出律等规律发生演化。 相似文献
13.
本文对大花蕙兰外植体消毒方式,原球茎增殖的培养基,大花蕙兰无根茵诱导生根培养基三个方面进行了系统的研究。结果表明：外植体在用A．1％Tween-60的1％HgCl2溶液消毒8分钟效果最明显,利于原球茎增殖的培养基为MS＋6-BA1．0mg／L＋NAA0．5mg／L,增殖系数为3．97,最佳的生根培养基为MS＋NAA0．2mg／1＋GA1．0mg／1＋香蕉泥150g／L,生根率最高可以达到100％。 相似文献
14.
研究了n进制非零数字之积函数均值的计算公式问题,采用初等方法,运用猜想、归纳、递推的办法.给出积函数均值的定义,得出了Smarandache问题中n进制非零数字之积函数三次均值的精确计算公式.解决了美籍罗马尼亚数论专家F.Smarandache教授著的Only problems,not solutions一书中的部分问题,对于Smarandache问题中的积性函数理论的研究起着重要的作用. 相似文献
15.
This research aims to improve the forecasting precision of electric quantity. It is discovered that the total electricity consumption considerably increased during the Spring Festival by the analysis of the electric quantity time series from 2002 to 2007 in Shandong province. The festival factor is ascertained to be one of the important seasonal factors affecting the electric quantity fluctuations, and the multiplication model for forecasting is improved by introducing corresponding variables and parameters. The computational results indicate that the average relative error of the new model decreases from 4.31% to 1.93% and the maximum relative error from 14.05% to 6.52% compared with those of the model when the festival factor is not considered. It shows that introducing the festival factor into the multiplication model for electric quantity forecasting evidently improves the precision. 相似文献
16.
在梅州的艺术长廊中,版画有着一段令人瞩目的历史。从20世纪30年代开始,梅州的版画艺术就在全国的版画艺术浪潮中唱响了号角,涌现了一批名垂历史的版画大家,他们为梅州的绘画艺术增添了绚丽的色彩。时至今日,当代版画的发展已经呈现多元化趋势,并向传统观念发出挑战。梅州版画如何在保持自身特色的同时,又要走向更广阔的天地,是今后梅州版画创作研究的课题。 相似文献
17.
<诗经>中有相当数目的情歌吟咏于水滨河畔或与雨水密切相关.究其深层原因,这与古人对水的崇拜分不开.古人认为,水乃万物之源,水蕴含着神奇的生殖力,人也从水出.因此,女人临水或与水接触,便能获取生殖繁衍能力,多子多孙. 相似文献
18.
This paper describes thereanalysis of data obtained in 1987 on themental calculation strategies used by asample of 11-year-olds
in the course of anational survey of schools in England,Wales and Northern Ireland. The mentalskills test was administered
to pupils in aone-to-one situation and the reanalysismade use of classifications of mentalstrategies developed in the past
decade ininternational research. These pupils werea subsample of the main sample of about 10000 who took a written test of
mathematicsin the survey, 247 taking both tests. Thescores on the written test were used todistribute these pupils into three
bands ofattainment in order to compare thefrequency and effectiveness of thestrategies used by pupils of differentlevels of
attainment. Eight of thereanalysed questions are discussed, each ofthem involving one of the four basicarithmetic operations.
Some are purelynumerical and in others the numbers are ina context. Top band pupils mostly preferredsequential strategies
which leave one ofthe numbers in the calculation complete,while the Bottom band generally preferredto split complete numbers
and operateseparately on the components of the numbersthus partitioned. The most popularstrategy for Middle band pupils in
severalquestions was the standard algorithm usedmentally. Complete number strategies werethe most successful for pupils in
all threebands. Possible implications for theNational Numeracy Strategy in Britain arediscussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
19.
由于矩阵的乘法运算不满足交换律,因此对矩阵A,B而言,在一般情形下,AB≠BA.通过对矩阵乘法的深入研究,利用分块乘法的初等变换,讨论了矩阵A,B的特征多项式之间、特征值之间、特征矩阵的秩之间等的关系,并进一步地得到矩阵乘积AB与BA的一些性质,所得结果是矩阵理论的补充和推广. 相似文献
20.
投资环境建设是发展经济的一项基础性工程，直接影响到资本、项目、人才、技术等的引进。投资环境建设的实质内容是建立起良好的资本运行秩序。各级政府作为投资环境建设的主体，应该从建设而不是仅仅从改善投资环境的角度来思考。为资本自然属性的实现创造良好条件。 相似文献