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1.
首次把p半线性映射引入到线性空间,并深入研究特征p域上的线性空间p半线性映射.给出了p半线性映射的一些基本性质,包含类似线性映射的一些性质和不同于线性映射的性质.  相似文献   

2.
根据缓冲算子的结构,提出了线性缓冲算子、线性弱化缓冲算子和线性强化缓冲算子及线性缓冲算子矩阵的概念;然后,给出了利用线性缓冲算子矩阵判断线性缓冲弱化算子和线性缓冲强化算子的方法.  相似文献   

3.
根据缓冲算子的结构,提出了线性缓冲算子、线性弱化缓冲算子和线性强化缓冲算子及线性缓冲算子矩阵的概念;然后,给出了利用线性缓冲算子矩阵判断线性缓冲弱化算子和线性缓冲强化算子的方法.  相似文献   

4.
研究多元线性模型在不等式约束下齐次线性估计和非齐次线性估计的可容许性, 刻画了二者之间的关系, 得到了齐次线性估计(非齐次线性估计)在齐次线性估计类(非齐次线性估计类)中是可容许的充要条件.  相似文献   

5.
利用缓冲算子的结构与性质,定义了线性缓冲算子、线性弱化缓冲算子和线性强化缓冲算子.研究了线性缓冲算子的复合运算及运算的性质,以及可逆线性缓冲算子及其性质,证明了可逆线性缓冲算子集合为线性缓冲算子群,为使用线性缓冲算子处理数据提供了数学理论依据.  相似文献   

6.
利用缓冲算子的结构与性质,定义了线性缓冲算子、线性弱化缓冲算子和线性强化缓冲算子.研究了线性缓冲算子的复合运算及运算的性质,以及可逆线性缓冲算子及其性质,证明了可逆线性缓冲算子集合为线性缓冲算子群,为使用线性缓冲算子处理数据提供了数学理论依据.  相似文献   

7.
讨论矩阵损失下带约束多元线性模型中线性估计的可容许性问题,证明了约束条件下多元线性模型中线性估计KB的可容许性与约束条件下一元线性模型中线性估计Kβ的可容许性具有等价性;根据这一特征得出了多元线性模型中线性估计KB的估计LY是可容许估计的充要条件。  相似文献   

8.
针对自适应线性神经网络的大量理论和应用文献都没有多层线性网络应用、讨论的现象,研究基于线性神经元作用函数,推导出多层的多输入/单输出和多输入/多输出的线性神经网络数学表达式,其函数形式等效于单层线性神经网络,同样是关于输入变量的线性关系,仅权值和阈值更加复杂而已.为了验证多层自适应线性神经网络与单层自适应线性神经网络的等效性,分别以两个线性函数的逼近为例,通过MATLAB软件仿真平台作了进一步的验证.仿真结果表明,多层线性神经网络能实现线性函数的逼近,但效果不如单层线性神经网络理想.因此,多层线性神经网络的功能完全可由单层线性神经网络精确地实现,多层线性神经网络的存在是没有必要的.  相似文献   

9.
主要研究半拓扑线性空间中半拓扑线性有界与完全半拓扑线性有界的关系,得到了半拓扑线性子空间中半拓扑线性有界的充分必要条件,以及半拓扑线性空间中半拓扑线性有界的等价条件.  相似文献   

10.
研究了一般增长曲线模型中线性可预测变量的最优预测,给出了可容许线性预测的定义,并分别在齐次线性预测类和非齐次线性预测类中得到了线性可预测变量的一个线性预测是可容许预测的充要条件.  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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

17.
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   

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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