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1.
本文对于一类形如F(x)=g(x,maxΦ_(ij)(x),…,maxΦ_(mj)(x))+h(x)的拟可微函数(在Demyanov和Rubinov意义下)给出了一种优化算法,其中g,Φ_(ij)分别为R~(m+n)和R~n上的连续可微函数,且g(x,y_1,…,y_m)关于每一个y_i都是非增的,h(x)为R~n上的凸函数。  相似文献   

2.
对于凸函数有如下性质:如果f、g均为R~1上的凸函数,并且对任意的x∈R~n,(?)f(x)==g(x),其中f(x)与g(x)分别表示f和g的次微分,则f(x)-g(x)=const。关于近似次微分,1984年,Loffe在文中提出了如下问题:设f、g是R上Lipschitz函数,并且(?)_nf(x)=(?)_ag(z),是否有f(z)-g(z)=const? 可以证明当f(x)为局部Lipschitz函数,且几乎处处满足正则条件时,可以得到肯定的结论。但从下面提出的例子可看出,对于一般情形,即,对一般的Lipschitz函数来说结论  相似文献   

3.
对于可微的函数,其二阶导数可以刻画函数的凸性.受这种思想的启发,邢志栋等人根据微分方程的极值原理给出了拟凸函数的一个充分条件,本文利用文献[1]中建立的定理1,给出了二次可微的预不变拟凸函数的一个充分条件.X关于η(x,y)为不变凸集,二次连续可微函数f(x)满足条件D,η(x,y)满足条件C且η(x,y)下有界,若(A)x∈X,2f(x) g(x)f(x)T是半正定的(其中g(x):X(∩-)Rn→Rn是下有界函数),则f(x)关于η(x,y)是预不变拟凸函数.本文的结论是对文献[2]中相应结论的推广.  相似文献   

4.
利用连续同伦算法讨论具有形式F(x)=x f(x)的组合映射F:R~n→R~n的零点的计算,其中f是二阶连续可微映射,给出了F零点存在的一个条件,在此条件下,本文给出的算法是整体收敛的。  相似文献   

5.
本文分别对R′到π(R′)上的集值映射A(x)=[a(x),b(x)]视其为三种类型的不可微函数(凸函数,局部Lipschitz拟可微函数)的广义梯度,讨论了它的积分问题。  相似文献   

6.
1 问题的描述在含有随机变量的复杂决策问题中所产生的二阶段有补偿问题通常具有如下形式这里D={x|Ax=d,x≥0}?R~n为约束区域,A∈R~(m×n),d∈R~m(m≤n),h(x)为x的实函数,Q(x)=EQ(x,ω),而Q(x,ω)为相应于样本点ω的随机变量并取第二阶段(补偿)问题的最优值.对于问题(1),已有算法均限于具有简单补偿和随机右端项的随机线性规划问题,并且算法比较  相似文献   

7.
研究了[a,b]上的有界变差函数与[a,b]上的可微函数之间的关系,得出了有界变差函数是准可微函数;函数f(x)为准可微函数当且仅当f(x)为近似有界变差函数。  相似文献   

8.
研究了如下的不可微多目标规划问题:(MP)min(f1(x)+s(xC1), f2(x)+s(xC2),...,fp(x)+s(xCp)), s.t. h(x)≤0, 其中函数 fiX→R, (i=1,2,...,p)和h=(h1,h2,...,hm)X→Rm在X上是连续可微的;Ci(i∈{1,2,...,p})是Rn上的紧凸集, s(xCi)表示集合Ci在x的支撑函数.在(C, α, ρ, d)-凸性的假设下,得到了不可微多目标规划问题弱有效解的Kuhn-Tucher型最优性充分条件.而且本文得到了原问题的Mond-Weir型对偶以及相应的对偶结果.本文所得结果推广了一些最新的结果.  相似文献   

9.
假设F: D?R~n→R~n在x~#连续以及在x~#某邻域S_0?R~n上G-可微,如解非线性方程组F(x)=0本文提出了NeWton-AOR方法,对初始值X~(k,0),定义?其中D(x~k),L(x~k),u(x~k)分别是F'(x~k)的对角矩阵,严格下三角和严格上三角矩阵,並且?讨论了{x~k}的收敛性以及在非线性椭圆型边值问题上的应用.  相似文献   

10.
设K是一个正整数。W~k(R~n)表示所有定义在R~n内的函数f(x)〔x=(x1,x2…,xn)〕使得它和它的S(|S|=sum from j=1 to n S_j≤K)阶广义导数都属于L~2(R~n)的函数的集合。对K=n=1,设H_0(R~1)={f(x);f和它的广义导数Df属于L~2(R~1),但f=f(a、e),这里f是绝对连续函数}。这篇文章的主要结果是:H_0(R~1)=W~1(R~1)。  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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