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1.
中介逻辑的谓词演算系统(Ⅱ)   总被引:1,自引:1,他引:0  
本文为参考文献[7]的续篇,在此继续生成中介逻辑的谓词演算系统MF的形式定理。定理10 MF:[1]x~A(x)~xA(x),[2]~xA(x)x~A(x)[3]~xA(x)x~A(x). 定理11 F:[1]x[A(x)→B(x)],xA(x)xB(x),[2]x[A(x)→B(x)],~xA(x)xB(x),[3]x[A(x)→B(x)],x~A(x)(x)B(x),[4]x[A(x)→B(x)],xA(x)xB(x),[5]x[A(x)→B(x)],x~A(x)xB(x),[6]x[A(x)→B(x)],xA(x)xB(x). 定理12 MF:[1]xA(x)∧Bx[A(x)∧B],x不在B中出现,[2]xA(x)∧BxA(x)∧B],x不在B中出现.[3]xA(x)∨Bx[A(x)∨B],x不在B中出现.[4]xA(x)∨Bx[A(x)∨B],x不在B中出现. 定理14 MF:[1]xA(x)∧xB(x)x[A(x)∧B(x)],[2]xA(x)∨xB(x)x[A(x)∨B(x)],[3]xA(x)∨xB(x)x[A(x)∨B(x)],[4]x[A(x)∧B(x)]xA(x)∧xB(x). 定理17 MF:[1]x[A(x)B(x)],x[B(x)C(x)x[A(x)C(x)],[2]x[A_1(x)B_1(x)],x[A_2(x)B_2(x)]x[A_1(x)∧A_2(x)B_1(x)∧B_2(x)],[3]x[A_1(x) B_1(x)],x[A_2(x)B_2(x)]x[A_1(x)∨A_2(x)B_1(x)∨B_2(x)].  相似文献   

2.
四阶两点常微分方程边值问题解的存在性   总被引:3,自引:0,他引:3  
讨论一类四阶两点常微分方程边值问题x(4)=f(t,x,x′,x″,x),边界条件的解的存在性,并给出相应的结论。其中边界条件如下:x(0)=A,x(1)=B,x″(0)=,x″(1)=, x(0)=A,x(1)=B,x″(0)=,x(1)=, x(0)=A,x(1)=B,x(0)=,x″(1)=, x(0)=A,x′(1)=B,x″(0)=,x″(1)=, x(0)=A,x′(1)=B,x″(0)=,x(1)=, x(0)=A,x′(1)=B,x(0)=,x″(1)=, x′(0)=A,x(1)=B,x″(0)=,x″(1)=, x′(0)=A,x(1)=B,x″(0)=,x(1)=, x′(0)=A,x(1)=B,x(0)=,x″(1)=。这些结论是在假设f(t,x,y,p,r)在形如[0,1]×Dx×Dy×Dp×I的区域内不变号的条件下给出的,其中Dx、Dy、Dp、I分别为某一区间。  相似文献   

3.
利用L iapunov函数法,给出两类方程…x g(x。)x。 bx。 f(x)=e(t,x,x,。x。)和…x g(x。)x。 f(x)x。 cx=e(t,x,x,。x。)零解全局渐近稳定性的充分条件,推广文献[1~4]中的相关结论.  相似文献   

4.
利用一不动点定理,对较同类具状态依赖时滞更为一般的非线性微分方程:x′(t)=-a(t,x(t))x(t)+f(t,x(t-1τ(t,x(t))),…,x(t-τm(t,x(t)))),x′(t)=a(t,x(t))x(t)-f(t,x(t-1τ(t,x(t))),…,x(t-τm(t,x(t)))),进一步研究,得到一些保证此类方程存在多个周期正解的充分条件而比相关研究有更好的结果.  相似文献   

5.
本文利用Galerkin方法和解的先验估计,研究了一类更广泛的Korteweg-de Vries方程的初边值问题。 u_t+f(u)_x-αu_(xx)+u_(xxx)=0 (x,t)∈R~+×[0,T] u(x,t)|_(t=0)=u_0(x) x∈R~+ u(x,t)|_(x=0)=0 u(x,t)→0 (x→∞)及 u_t+f(u)_x-u_(xxx)=0 u(x,t)|_(t=0)=u_0(x) x∈R~+ u(x,t)|_(x=0)=u_x(x,t)|x=0=0 u(x,t)→0,(x→∞)弱解的存在性,在适当的条件下,还可以得到古典解的存在性。  相似文献   

6.
讨论了余弦积分函数Ci(x)与正弦积分函数Si(x)的Hilbert变换,证明了Ci(x)与-sgn(x)Si(|x|)构成Hilbert变换对,即Ci(x)-isgn(x)Si(|x|)为解析信号,同时求出了Si(x)的Hilbert变换,证明了Si(x)与Ci(x)-Ci(0)构成Hilbert对.  相似文献   

7.
利用上下解方法和Schauder不动点定理,讨论了一类六阶两点边值问题x(6)(t)-f(t,x(t),x′(t),x″(t),x(4)(t),x(4)(t),x(5)(t))=0,t∈(0,1)x(0)=x′(1)=x″(0)=x″(1)=x(4)(0)=x(5)(1)=0,解的存在唯一性.  相似文献   

8.
分段函数与初等函数之间的关系   总被引:4,自引:0,他引:4  
讨论形如 f(x) =f1(x) ,x x0 ,f(x) =f1(x) ,x x0等以及两个和两个以上连接点的分段函数是否是初等函数的问题 ,并得到相应的判别法 .  相似文献   

9.
考虑二阶具正负系数非线性时滞差分方程Δ2 x(n) f(n ,x(n) ,x(σ(n) ) ) - g(n ,x(n) ,x(σ(n) ) ) =0及Δ2 (x(n) -a(n)x(δ(w) ) ) f(n ,x(n) ,x(σ(n) ) ) - g(n ,x(n) ,x(σ(n) ) ) =0 其中Δ是向前差分算子 ,Δx(n) =x(n 1 ) -x(n) ,Δ2 x(n) =Δ(Δx(n) ) ,获得了方程所有有界解或者振动或者趋于 0的充分条件  相似文献   

10.
导数定义公式的一个推广及其应用研究   总被引:1,自引:0,他引:1  
将导数在某一点的定义f(x0)=lim(h→0)f(x0+h)-f(x0)/h推广为f(x0)=limf[x0+α(x)]-f[x0+β(x)]/α(x)-β(x)(α(x)→0,β(x)→0),从而简化了有关导数定义一类问题的求解.  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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