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1.
数学问题意识、问题提出能力的调查研究   总被引:1,自引:0,他引:1  
参照国、内外量表的设计并结合我国的实际情况,编制了数学问题意识、问题提出能力的问卷;通过问卷调查,考察问题意识、问题提出能力的年级差异是否显著,学生之间的数学问题意识、问题提出能力是否存在差异,存在哪些差异。  相似文献   

2.
在一般线性规划反问题的基础上,考虑广义规划问题的反问题。利用线性规划的最优性条件,给出了(GUB)问题在l1模意义下的反问题的数学模型及求解方法。并且我们给出了把(GUB)问题的反问题转化为它的对偶问题求解的一种方法,若在给定(GUB)问题的一个0-1可行解,并且(GUB)问题的一个最优解的所有分量是在0与1之间的条件下。  相似文献   

3.
地球问题是指在地球表层系统中存在的一系列阻碍或破坏人类生存的发展,并得到全球社会普遍关注的事件与现象。本文探讨了跨世纪地球问题的确认条件,表现以及科学预言在确认地球问题中的作用。  相似文献   

4.
通过调整核函数K(x,t)满足的边界条件讨论一般边界条件下逆Sturm-Liouville问题的求解.同时对包括势函数q(x)对称在内的多种情况证明了逆Sturm-Liouville问题解的唯一性.最后讨论已知势函数q(x) q(1-x)所对应的一列谱如何求解逆Sturm-Liouville问题.  相似文献   

5.
讨论离散型问题与连续型问题的相互转换,用例题进行说明,归纳出解题方法和基本思路.  相似文献   

6.
本文概要介绍了问题、问题解决与问题解决教学的涵义,并在此基础上,详细论述了制约问题解决教学的因素。  相似文献   

7.
仅从如何建立物理模型、如何构建符合物理规律的数学模型或图像、利用定性或半定量的估算等几个方面给出实际问题向物理学问题转化的途径.  相似文献   

8.
仅从如何建立物理模型、如何构建符合物理规律的数学模型或图像、利用定性或半定量的估算等几个方面给出实际问题向物理学问题转化的途径.  相似文献   

9.
本文综述了正的斯图谟—刘维尔特征值问题(简称S-L问题)的定性性质,介绍了S—L方程特征反问题的提法、解的存在唯一性,以及由特征数据构造势函数q(x)的条件和方法,最后探讨了反问题在物理、力学中的应用。  相似文献   

10.
数学问题意识、问题提出的涵义及因素分析   总被引:7,自引:6,他引:1  
研究数学问题意识、问题提出的一般理论,对它的涵义进行界定,分析它的特征和因素.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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