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1.
王永超  刘君 《长春大学学报》2002,12(4):16-17,23
通过无限小变换,把向量叉乘转换为矩阵运算,在引入向量的相伴矩阵的基础上,给出二重向量叉乘的转换法。最后引入惯量张量的矩阵法。  相似文献   

2.
根据向量代数运算的几何定义先推出各代数运算的坐标表示。利用这些坐标表示可简化所有运算律的证明;从而为解析几何中向量代数有关部分的教学处理提供了一个简明易懂的新方法。  相似文献   

3.
李凤 《科技资讯》2013,(25):188-189
中学向量内容主要是向量的线性运算与向量的数量积.而向量的数量积几乎可以解决几何所有度量问题,如长度、夹角、平行、垂直等,这使一些解析几何、立体几何中定理、公式的推导大为简化,大大降低了数学难度.  相似文献   

4.
作为推理的基础,时间的表示方法是一个基本的要素。文中为Allen的区间代数理论中区间的关系表达提出了向量表示法,称之为关系向量。其后,给出了定义在关系向量上的几种运算,并将其运用于时态推理中。这种方法把原先的矩阵表示法降为向量表示,从而较好地减少了时态推理计算量,并易于计算机实现。  相似文献   

5.
平面向量及其应用   总被引:1,自引:0,他引:1  
<正>向量及其运算是高中教材的新增内容。作为现代数学重要标志之一的向量引入中学数学后,给中学数学带来无限生机。由于向量融数、形于一体,具有几何形式与代数形式的"双重身份",使它成为中学数学知识的一个交汇点,成为联系多项内容的媒介。因此向量的引入,大大拓宽了解题的思路与方法,使它在研究其它问题时获得了广泛的应用。  相似文献   

6.
在高中引出向量及其运算,使高中数学与高等数学联系更为紧密。利用向量及其运算知识解立体几何求值题,进一步反映了立体几何中有关概念的本质,可避免添加辅助线或辅助面等,亦可使方法和过程更为简明。  相似文献   

7.
解决向量空间中8条运算公理在有理数域Q上的独立性问题,并指出[1]中一不足之处。  相似文献   

8.
提出一种直接列写电路节点电压矩阵方程的方法,通过直接建立独立源、受控源和控制变量等向量的KCL,KVL方程,使节点电压矩阵方程直接写出。该法可适用于含有各类受控源的电路,进行矩阵运算便可得到节点电压解向量和任意输出解向量。  相似文献   

9.
针对服务质量(QoS)要求严格的一类分布式应用,通过寻找近似最优的副本部署方式解决QoS感知的副本放置问题,使系统能够满足所有用户的QoS需求.在服务质量距离的基础上建立了一种基于图论的抽象副本放置模型,并提出一种集合覆盖预处理与向量运算相结合的快速启发式算法(CORePA).该算法首先引入集合覆盖的思想,通过拓扑预处理消除冗余节点以降低问题规模;然后通过矩阵和向量表示简化处理过程,并充分考虑副本开销作为启发信息,利用向量操作降低算法开销.实验和分析表明:与现有方法相比,CORePA算法速度更快,在不同节点规模下可获得更好的副本策略,且具有稳定性和高效性的特点.  相似文献   

10.
针对支持向量机算法耗时较长的问题,利用并行计算思想,基于图形处理器对多类支持向量机算法——Crammer-Singer算法进行改进,并利用循环展开、数据暂留、缓存和开放运算语言等技术对算法加以实现.分别在4个数据集上对原算法和改进算法进行对比实验,结果表明,改进算法在性能上获得了较大提升.  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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