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1.
讨论了具有滞后的中立型定常线性控制系统:X(t)=A1X(t)+A2X(t-τ1)+A3X(t-τ2)+B1U(t)+B2U(t-τ3),Y(t)=C1X(t)+C2X(t-τ4),与无滞后的定常线性控制系统X(t)=A2X(t)+B1U(t)Y(t)=C1x(t)。在镇定理论方面的有关问题,并且得到了该系统的滞后量范围 工,所得结论推广了前人的结果。  相似文献   

2.
设(X,T)是T2空间,T1是拓扑T的基,A是*X上的内代数,ν是A上的内测度,本文用无穷小方法证明了:在k-饱和的非标准模型中,若X是正则空间,且对每一T∈T1,*T∈A,则对X的每一Borel集B,st-1(B)∈Lu(A)∩ns(*X),且νst-1|F(X)是τ-光滑Borel测度,νst-1|F(X)是Radon测度;若对每一T∈T,*T∈A,并且对每一T∈T及每一ε∈R+,有闭集CT,使L(ν)(*T-*C)<ε,则对每一Borel集B,st-1(B)∈L(ν,A)∩ns(*X)且νst-1|F(X)是正则τ-光滑Borel测度.文中并讨论了这些结果在测度扩张中的应用  相似文献   

3.
设A为Banach空间X上强连续C-余弦算子函数C(t)的母元,则C(t)C ̄-1为R9c ̄2)上的(无界)余弦算子函数,本文给出了A与C(t)C ̄-1之间的谱映射定理。  相似文献   

4.
设A为Banach空间X上强连续C-余弦算子函数C(t)的母元,则C(t)C^-1为R(C^2)上的(无界)余弦算子函数,本文给出了A与C(t)C^-之间的谱映射定理。  相似文献   

5.
考察了A1Et2C1/t-BuC1引发体系的α-蒎烯阳离子聚合反应行为。结果表明,A1Et2C1单独不能引发α-蒎烯聚合,与t-BuC1复合后才具有引发活性。其引发活性随t-BuC1/A1Et2C1的不同而变化,质谱分析表明α-蒎烯聚合产物中存在t-BuC1和基(CH3)3C,证明t-BuC1参与了链的引发反应。进一步实验还有表明:t-BuC1与A1Et2C1相互作用除生成活性物质Bu^+AlEt  相似文献   

6.
第一节在没有指数有界的假设条件下,讨论了积分C-半群的一些性质,以及积分C-半群与C-半群的关系,推广了[5,定理2]。第二节讨论了积分C-半群的谱映射定理。主要结果如下:设A为积分C-半群{T(t)}的生成元,ρc(A)≠Φ,则(i)t>0(ii)(a)反之,若存在x∈X,x≠0,使得对任何t>0那么,(A)。(b)若(A),则对任何t>0,t(T(t)C-1)。反之,若对任何t>0,t(T(t)C-1),且存在X∈X,X≠0,使得T(t)Cx=tX,则,0(A)(iii){(t)。  相似文献   

7.
OA能诱发人神经母细胞瘤SK细胞进行编程死亡.死亡细胞缩小变圆,细胞质凝聚,DNA有控降解成约200bp左右的片段,且这一过程可由蛋白质合成抑制剂亚胺环己酮(CHX)抑制.将编码Bc1-2全长蛋白质的cDNA植入pXJ41neo载体中,使其表达由HCMV病毒启动子控制.形成的顺义(pBcl-2-S)及反义(pBcl-2-AS)表达质粒经转染导入SK细胞中获得稳定转染子,West-ern印迹表明顺义转染子表达较大量的26kdBc1-2蛋白,而反义转染子则不表达.增强表达的Bc1-2基因产物对OA引SK细胞编程死亡无抑制效应.  相似文献   

8.
本文考虑含有n个未知矩阵X1,X2,X3,…,Xn的非齐次矩阵方程:A1X1B1+A2X2B2+…+AnXnBn=F,(1)其中Ai∈Cm×li,Bi∈Cpi×q,Xi∈Cli×pi,Fi∈Cm×q.我们先给出一个求解的方法;然后利用矩阵的拉直运算和...  相似文献   

9.
关于C0—算子半群的紧扰动   总被引:1,自引:1,他引:0  
设A是Banach空间X中的C0-算子半群e^tA的无究小生成,K是X中的有界线性算子,本文证明了Δ(t)=e^t(A+K)-e^tA对t〉0是紧算子当且仅当Δ(t)对t〉0按一致算子拓扑连续且对λ∈p(A)(A的豫解集),(λ-A)^-1K(λ-A)^-1是紧算子。此外若X是可分Hilbert空间,则Δ(t)对t〉0按一致算子拓扑连续的条件等价于对τ〉ω(A)(e^A增长界),lim│ω│→∞‖  相似文献   

10.
在MRSDCI/DZ+P水平上,计算了SiC2分子7个电子态X^1A1,^3B2,^1B2,^3B1,^1B1,^3A2和1^A2的平衡构型和激发能。所得X^1A2和^1B2态的平衡构型以及X^1A2→^1B2的激发能和实验值符合很好。  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.
<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   

20.
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