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1.
严格不变拟单调性   总被引:1,自引:0,他引:1  
本文对严格拟单调进行推广,定义了严格不变拟单调:设K为Rn中的不变凸集,η:Rn×Rn→Rn,如果f是不变拟单调的,且对x,y∈K,x≠y,存在z∈{y λη(x,y):λ∈(0,1)},使得η(x,y)Tf(z)≠0,则称f为集合K上相对于η的严格不变拟单调映射.并建立了严格不变拟单调与严格预拟不变凸之间的关系:设K为Rn中的不变凸集,f是K上的可微函数,η:Rn×Rn→Rn,如果η满足文中所述条件1,则f是集合K上相对于η的严格预拟不变凸函数的充分必要条件是f是集合K上相对于η的严格不变拟单调,且对所有x,y∈K,有f(y)≤f(x)f(y η(x,y))≤f(x)成立.  相似文献   

2.
提出了一类新的向量值映射-D-半预不变真拟凸映射,它是D-预不变真拟凸映射与D-半预不变凸映射的真推广。首先,给出例子说明半不变凸集、D一半预不变真拟凸映射的存在性;然后,给出了相关集合的稠密性结果以及在下D-半连续条件下D-半预不变真拟凸映射的判定,并建立了D-半预不变真拟凸映射与D-严格/半严格半预不变真拟凸映射间的关系;最后,讨论了D-半严格半预不变真拟凸映射在向量优化问题中的一个应用,并举例验证了所得结论的正确性。  相似文献   

3.
讨论了集值映射的严格不变拟单调性与Clarke次微分意义下不可微函数的严格预拟不变凸性.  相似文献   

4.
文献[5]在前人的基础上证明了半严格预拟不变凸函数的一个充分条件,即在一定条件下可微的伪不变凸函数关于相同的向量值函数η为半严格预拟不变凸函数.本文将此结论推广到了非光滑的情形,利用Clarke次微分理论和条件C,证明了在关于向量值函数η的开不变凸集上,满足局部Lipschitz条件的伪不变凸函数关于相同的向量值函数η...  相似文献   

5.
【目的】研究预(拟)不变凸性的一些等价刻画。【方法】将多元实值函数f 转化为单变量实值函数φ来处理预(拟)不变凸性。【结果】首先,当条件C1和条件D成立时,f的预(拟)不变凸性等价于φ的(拟)凸性;其次,利用类似的方法获得了中间点预(拟)不变凸性的等价刻画;最后,给出了这些结论的一些应用。【结论】f的预(拟)不变凸性可以等价转化为φ的(拟)凸性;然而,ρ-预(拟)不变凸情形却有些不同,即φ的ρ-(拟)凸性是与f 的弱ρ-预(拟)不变凸性相对应的。
  相似文献   

6.
借助于n维模糊数空间上的偏序关系, 提出和定义了n维模糊映射的预不变凸性, 包括n维模糊映射的预不变凸、严格预不变凸、弱严格预不变凸、预拟不变凸、严格预拟不变凸、弱严格预拟不变凸性;进而讨论了各种预不变凸性之间的相互关系;并对其相互关系进行了举例说明。  相似文献   

7.
在Banach空间中,定义了含参变数的映射的Adjacent导数及不变类凸、拟不变类凸和伪不变类凸.给出了参变数优化问题的向量Lagrange函数和向量Kuhn-Tucker条件.提出了参数优化问题的几个最优性充分条件.  相似文献   

8.
讨论了集值映射的半严格不变拟单调性与Clarke次微分意义下不可微函数的半严格预拟不变凸性.  相似文献   

9.
提出了一类新的向量值映射—D-半预不变真拟凸映射,它是 D-预不变真拟凸映射与D-半预不变凸映射的真推广。首先,给出例子说明半不变凸集、D-半预不变真拟凸映射的存在性;然后,给出了相关集合的稠密性结果以及在下D-半连续条件下D-半预不变真拟凸映射的判定,并建立了D-半预不变真拟凸映射与D-严格/半严格半预不变真拟凸映射间的关系;最后,讨论了D-半严格半预不变真拟凸映射在向量优化问题中的一个应用,并举例验证了所得结论的正确性。
  相似文献   

10.
在Banach空间中定义了一种新的广义凸函数——半严格拟不变凸函数。举例说明了半严格拟不变凸函数是比拟不变凸函数和伪不变凸函数更为广泛的一类广义凸函数。对于非光滑的半严格拟不变凸函数,讨论了它的C larke广义次微分性质。讨论了半严格拟不变凸函数与拟不变凸函数之间的关系。此外,在这篇文章里,还给出了半严格拟不变凸函数的两个基本性质。本文的结果扩充了无限维空间中的凸性理论。  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.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

16.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

17.
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   

18.
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   

19.
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   

20.
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   

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