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1.
代数格的拓扑刻画   总被引:1,自引:1,他引:0  
利用拓扑学理论讨论了代数格,强代数dcpo以及强代数格上的Scott拓扑,得出了一个拓扑若是超-coherent的当且仅当它与某个强代数dcpo上的Scott拓扑一致,其超紧基在交运算下非空且封闭当且仅当它是某个代数格上的Scott拓扑.  相似文献   

2.
研究了上定向的具有Riesz分解性质的广义效应代数的结构.引入了广义效应代数中素理想的定义,证明了上定向的具有Riesz分解性质的广义效应代数是有限次直既约的当且仅当它是反格;上定向的具有Riesz分解性质的广义效应代数通过理想得到的商代数是反格当且仅当此理想是素理想.最后证明了上定向的具有Riesz分解性质的广义效应代数具有子直积表示.  相似文献   

3.
研究了几类效应代数的张量积及其可表示性.证明了两个效应代数关于不同的双态射的张量积是同构的,通过构造适当的双态射,给出效应代数{0,1}E、Cm(a)Cn(b)、C2(x)C4(y,z)及C2(x)C′4(y,z)的具体形式,结果表明:{0,1}E是可表示的当且仅当E是可表示的,Cm(a)Cn(b)与C2(x)C4(y,z)都是可表示的效应代数,但C2(x)C′4(y,z)是不可表示的效应代数.  相似文献   

4.
基于连通集的定义,引入了c-理想的概念,得出了连通代数domain中每一个元都是相容紧元,当且仅当它的每个c-理想都是主c-理想,给出了连通代数domain满足升链条件.研究了连通完备偏序集A中的每个元是相容紧元的充要条件是A与A的c-理想格同构.最后,证明了连通代数domain范畴与偏序集范畴等价.  相似文献   

5.
本文在定向空间的基础上通过收敛的方式定义了拟连续空间和交连续空间,推广了Domain理论中的相应结果.主要结果如下:(1)一个T_0空间是拟连续的,当且仅当它是局部强紧的,当且仅当它的开集格在集包含关系下是超连续格,当且仅当它的sober化是拟连续dcpo;(2)一个定向空间是交连续的当且仅当它的闭集格在集包含关系下是一个Frame;(3)一个T_0拓扑空间是c-空间当且仅当它既是交连续的又是拟连续的.  相似文献   

6.
利用Nevanlinna代数体函数的值分布理论,讨论了代数体函数微分单项式的值分布问题,得到了:设w(z)是一个v值代数体函数,那么当n≥(l2+2σ+2l0+4)v-2σ-2时,(w’)i1…(w(n))in(w(z))n取任意非零有限复数无穷多次,除非w(z)是代数函数.  相似文献   

7.
设B是一个超有限因子,T(N)是B中的正则套代数.给出了T(N)中的Lie理想的结构.证明了T(N)的一个σ-弱闭子空间L是T(N)的Lie理想当且仅当存在T(N)的一个σ-弱闭的结合理想J和T(N)的对角部分的中心的子空间E,使得J0LJ+E,其中J0为J中的迹为零的元的集合.  相似文献   

8.
蕴涵格、弱Ro代数与正则剩余格   总被引:2,自引:0,他引:2  
讨论了蕴涵格、弱Ro代数以及正则剩余格之间的相互关系,证明了以下结论:(1) 弱Ro代数既是蕴涵格又是正则剩余格;(2) 蕴涵格L是正则剩余格(弱Ro代数)的充分必要条件是:对任意x,y,z∈L,x→(y→z)=y→(x→z);(3) 正则剩余格L是蕴涵格(弱Ro代数)的充分必要条件是:对任意x,y,z∈L,x→y∨z=(x→y)∨(x→z).  相似文献   

9.
M-阶化广义李超代数H(n)的导子超代数   总被引:2,自引:2,他引:0  
给出了M-阶化广义李超代数H(n)的定义,证明了M-阶化广义李超代数H(n)是Z-阶化的,刻画了H(n)的导子超代数的Z-阶化成分,进而确定了M-阶化广义李超代数H(n)的导子超代数.  相似文献   

10.
《河南科学》2017,(10):1567-1569
借助于效应代数中的主元研究了效应代数中的理想.证明了[0,e]是效应代数E的理想当且仅当e是E中的主元;在序列效应代数E中,E_p=E_S;特别地,在Hilbert空间效应代数ε(H)中,[0,P]是ε(H)的理想当且仅当P是H上的投影算子.  相似文献   

11.
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   

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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
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   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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