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1.
本文通过讨论一类非线性差分方程Δ(x_n-p_nx_(n-τ))+sum from i=1 to k(q_i(n))muitiply from j=1 to m_i(|x_n-σ_y|α_ySgnx_n)=0,n≥0最终正解的存在性,得到了差分方程Δ(x_n-x_(n-τ))+q(n)muitiqly from j=1 to m_i(|x_n-σ_j|α_jsgnx_n)=0有最终正解与方程Δ(x_n-x_(n-τ))+1/τq_nx_n~α=0有最终正解的等价性。  相似文献   

2.
正形置换具有良好的密码学性质,可用于分组密码的设计以抵抗密码分析。正形置换目前还没有成熟的构造方法。本文从正形拉丁方截集的角度出发,通过正形拉丁方的增长实现了由n-bit正形置换生成(n+1)-bit正形置换的构造过程。该方法能够迭代产生大量的非线性正形置换,而且算法形式简洁,可用于动态产生正形置换。本文的结果提供了一个研究正形置换结构和构造方法的新思路。  相似文献   

3.
本文主要采用Riccati变换,研究二阶中立型非线性时滞差分方程△(an(△xn+Pnxn-τ))γ)qf(n,xσ^α(n)+τnf(n,xσ^β(n))=0的振动性问题,给出新的判据,推广和改进了已有的结果。  相似文献   

4.
在用特定系数法把一个n元齐次对称多项式f(x_1,x_2,…x_n)表成初等对称多项式的多项式(σ_l,σ_2,…,σ)这一问题中。根据对称多项式基本定理的存在性和唯一性,在满足:l、f的首项应先于f_1的首项,再个f_i的首项先于f_i+1的首项;2、fi首项的指数组r_1,r_2,…,r_n满足r_1≥r_2≥…≥r_n;3、fi的首项的次数都等于f的次数r,即  相似文献   

5.
本文研究了一类非公度系统中电子运动的能谱及其与电子动力学性质的联系 ,分析了体系的本征能量E与参数λ的关系 ,计算了自关联函数C(t)和均方位移σ(t) ,分析其长期行为 ,发现当体系各态均为扩展态时 ,σ(t)~t1,C(t)~t- 1,当体系中仅存在局域态时 ,σ(t)~t0 ,C(t)~t0 ;当体系在复杂相区时 ,体系的长期行为 ,即t→∞时 ,σ(t)~t1。  相似文献   

6.
本文给出等差数列的两个判定方法,供学习中参考,现举例说明其方法和应用.1 通项公式是n的一次式,即通项公式判定法.数列{a_n}为等差数列的充要条件是a_n=pn+b(p,b为常数)证:必要性,设{a_n}是公差为d的等差数列,则:a_n=a_1+(n-1)d=d_n+(a_1-d)记:d=pa_1-d=b ∴a_n=pn+b(充分性)若a_n=pn+b(p,b为常数)则a_(n+1)=p(n+1)+b ∴a_(a+1)-a_n=p(n+1)+b-pn-b=p(n=1,2,3…)故{a_n}是等差数列.∴数列{a_n}是等差数列的充要条件是a_n=pn+b(p,b为常数)2 前n项的和是n的二次式(不含常数项)即前n项和判定法.  相似文献   

7.
考虑如下纵向数据半参数回归模型:yij=xijβ+g(xij)+еij,i=1,2,…,n,j=1,2,…,mi,结合现有文献,利用最小二乘法和非参数权函数估计方法给出了模型中参数分量β,回归函数g(.)和误差方差σ2的估计量形式,并在适当条件下,证明了它们的r(r≥2)阶平均相合性。这些结果是截面数据半参数回归模型yi=xiβ+g(xi)+еii=1,2,…,n,的研究基础上的推广。  相似文献   

8.
在本文中,通过对图族Q(S3,Cs,Cl,Ch)的σ-指标的研究,刻画出了图族Q(S3,Cs,Cl,Ch)的σ-指标的最大值序列、最小值序列、最大值及最小值.  相似文献   

9.
在B3LYP/6-311 G**[I-离子使用赝势基组(4s4pld)/(2s2pld)]水平下得到X-.H2O(X=F,Cl,Br,I)复合物优化构型。经MP2校正电子相关能及基组叠加误差(BSSE)在相同基组下单点校正,求得精确的单体间相互作用能的大小。由自然键轨道(NBO)分析揭示了相互作用的本质,阐述了相互作用的强度以及它对复合物构型和振动参数的影响。经分析得到电荷由X-离子的孤对电子迁移(CT)到σ*OH(…X)反键上,σ*OH(…X)的自然布居数增加,削弱了σOH(…X)键使σOH(…X)键增长,力常数变小,导致红移(与单体H2O相比),与实验值非常吻合,且它们之间具有很好的相关性,同时,红移强度加强。  相似文献   

10.
运动诱发大鼠在体心脏心肌顿抑现象的研究   总被引:3,自引:0,他引:3  
方法:成年雄性SD大鼠22只,随机分为A组(对照组,n=8)和B组(运动组,n=14);根据运动后心电变化又将B组随机分为B1组(心电异常组,n=8)和B2组(心电未异常组,n=6);连续测定运动前后不同时相心电图、左心室收缩功能,并于运动后110分钟行心肌HE染色.结果:(1)B1组在运动后出现心电异常,表现为J点下移、T波低平或倒置、ST-T下移等;(2)大负荷运动后B1组LVESP、+dp/dtmax出现两次升降现象,第二次升降为心肌顿抑现象发生,B2组未见明显第二次升降变化;(3)三组HE染色评分两两组间比较无显著性差异.结论:大负荷运动可以诱发心肌顿抑现象发生,表现为异常心电、短时可逆性心肌收缩功能障碍和心肌组织染色变化不明显.  相似文献   

11.
Since the late 1960s,culture has been considered tighter with communication.Culture IS based on the community of communication.Communication involves people and their environment.Thus culture is an important factor in communication.Today with modem economic and technological development,intercultural communication is mole important than ever before. When people from different cultural background communicate with each other,their social stereotype pattern of behavior, their habits of language and thought differ from one another,because these are the possible factors that affect intercultural communications.Culture norms also change,culture may be transferred as signs but we have to study and understand the above carefially.  相似文献   

12.
The thesis mainly discusses the character of the heroine in Charlotte Brontes famous novel "Jane Eyre". There are three major parts-introduction,analysis which is the main body of the thesis,and conclusion.Jane Eyre,the heroine,is a new woman image who requires independence equality and freedom.The thesis just analyzes Janes these rebellious characters through four peroods of her experiences.First,in her childhood,she has shown her rebellious spirit.As an orphan,Jane suffers a lot of misery.Not only her aunt treats her cruelly,her cousins despise her,but also do servants have a prejudice against her.In Janes immature heart, she is unwilling to bear ill treatment.She rebels them bravely.Second,when she studies at Lowood,her rebellious spirit is exposed furtherly.Her view doest stay in Mrs Reeds,instead turns to the whole society.She makes hypocrisy of so-called charity to be discovered completely.At the same time,she declares her independent,equal rebellious thought to her friend-Helldn who endures oppression willingly.Third,she,as a governess in Thornfield Hall falls in love with Rochester-her master.During this period,her thought grows into maturity.Thought she loves him passionately,she never loses her dignity and independence for him.When she knows his mad wife still lives,she makes up her mind to leave him.For she doesnt want to become his mistress.Fourth,her refusal of St Johns proposal of marriage depicts Janes character.She knows John does not love her at all and his purpose of marriage is only to perform his great task missionary.Jane does want to become a sacrifice.She breaks traditional morality,then she goes back to Rochester.  相似文献   

13.
The context of a word consists of the other words surrounding it and the situation in which it is used.When we come across a new word in our reading,instead of looking it up in a dictionary for its definition,we can guess its meaning from its context.  相似文献   

14.
当代中国武术经历了时代的沧桑和变迁,在历经了文化和历史的发展与洗礼之后,依然发展、繁衍至今。在这样一个漫长的过程中,伴随着以社会环境和社会人群价值取向为主的变迁与变化,当代中国武术的发展与当代社会的发展正逐渐的呈现出某些相背离和不和谐的表象。通过研究,我们发觉中国武术中原本一些内在的东西正在不断的被遗忘,正在不断的流逝。本文试从中国武术在当代发展中的问题境域入手,解读中国武术在当今世界和社会中存在的一些问题,希望能够从中找到中国武术发展的"合法性"或"合时性"的内在依据,以挺立中国武术的脊梁。  相似文献   

15.
Introduction Whatisculture?Toputitsimply,culturemeansthe totalwayoflifeofaperson.Thissimpledefinitionimplies thatculturereferstothepattersofcustoms,traditions,socialhabits,values,beliefsandlanguageofasociety.As cultureissoinclusive,itincludesvirtuallyeverythingthat agroupofpeoplethink,say,doandmake.Followingthedefinitionofsociologists,theterm culturereferstothetotalpatternofbeliefs,customs,institutions,objects,andcharacterizesthelifeofhuman community.“Cultureconsistsofallthesharedproductsof …  相似文献   

16.
"Midnight"is a poem written by Archibald·Lampman,a Canadian poet,who loved nature very much,but his poor health prevents him from being very active in the outdoor life.So he is often the quite,thoughtful observer of nature in his poems.This article mainly talks about how to appreciate the poem in the following aspects:word selecting,rhyme,sentence structure and atmosphere.After reading this poem,we cannot get rid of the air of horror and mystery."Midnight" reveals another aspect of the nature:wild,rough and unknown.There is something else in the nature that can awe human beings even though we don't know what it is.  相似文献   

17.
Chapter Ⅰ Introduction Sitting in the rocking chair,Carrie dreams her future.This is the deep impression the novel"Sister Carrie"gives us,which is written by Theodore Dreiser(1871-1945),the great American realism writer.  相似文献   

18.
国外锻炼行为理论研究综述   总被引:22,自引:2,他引:22  
正确认识和促进与健康有关的锻炼行为必须以合理的理论为基础。对国外锻炼心理学领域与健康有关的锻炼行为理论和模型:健康信念模型、保护动机模型、合理行为模型、计划行为模型、自我决定模型、社会认知模型、自我效能模型和跨理论模型进行分析,评价其成功和不足的地方。在前人研究的基础上提出态度-行为综合模型作为研究锻炼行为参与新的研究方向。  相似文献   

19.
我国普通高等院校体育教育效果调查与分析   总被引:8,自引:0,他引:8  
以全国高等教育科学"十五"规划重点课题<对我国普通高校体育教育效果的调查>调查结果为依据,通过调查大学生对高校体育教育的态度、认识水平、学习的获得和养成性等方面情况,分析了21世纪初以"健康第一"为指导思想的高校体育教育对在校大学生的作用和影响,发现和揭示了高校体育教育过程中存在于深层与潜在的问题,并以此为基础,对高等学校体育教育的效果进行客观评价,为推进高等院校体育的进一步改革提供依据.  相似文献   

20.
同义词的语用研究   总被引:1,自引:0,他引:1  
从语义学的角度来研究同义词只是同义词研究的出发点和基础,我们必须在此基础上进一步研究在实际的语言交流和运用中如何得体而恰当地运用同义词。同义词的语用研究把同义词的研究范畴从传统的语义学研究范畴延伸到了语用学、修辞学、心理学等研究范畴,因为这些学科本身就是密切联系的。只有这样,同义词———这些看似“相似的词语”才能有用武之地,才能丰富和美化我们的表达,使我们的语言表达准确而得体。  相似文献   

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