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1.
裴道武 《陕西师大学报》1995,23(4):12-16,20
模糊逻辑函数的计数至今仍是一个未解决问题,本文利用模糊逻辑函数析取范式的存在唯一性,引进基本片语集合,Aj,G(a)及G(a1,…Gk),推导出G(a),G(a1,…,ak)G(a)∩Aj以及G(a1,…,ak)∩Aj的计数公式,并给出了n元模糊逻辑函数的一个计数公式。  相似文献   

2.
设Cn〈a1,a2,…,ak〉是个循环图,t(G)是图G的支撑树数。本文利用第二类Chebyshev多项式给出了t(Cn〈1,3〉,t(Cn〈2,3〉),t(Cn〈1,2,3〉),t(Cn〈1,5〉),t(Cn〈3,5〉),t(C2n〈1,2,n〉)的公式。一个具体的例子表明,利用Chebyshev多项式的性质,即使n很大,这些公式的值是不难得到的。  相似文献   

3.
用半经验的紧束缚方法sp3s*计算了薄层应变超晶格(InxGa1-xAs)n/(GaAs)n(001)的电子结构.给出了组份X为0.53的超晶格(InxGa1-xAs)n/(GaAs)n的带隙值随层厚n的变化关系,以及超晶格(InxGa1-xAs)12/(GaAs)12的带隙值随组份X的变化关系.在得到超晶格能量本征值和本征函数的基础上,计算了该超晶格系统的光学介电函数虚部,并与体材料GaAs和体合金InxGa1-xAs的光学性质作了比较.计算结果表明,应变超晶格在较宽的能量范围有较好的光谱响应.  相似文献   

4.
证明了图的逻辑积的色数公式x(G1∧G2∧…∧Gn)≤min{x(G1),x(G2),…,x(Gn)},边色数有并作如下猜想:x(G1∧G2∧…∧Gn)=min{x(G1),x(G2),…,x(Gn)}.  相似文献   

5.
以Jacobi多项式的零点作为插值的节点,构造了一个组合型的Bernstein多项式算子Cn(f,x).若f(x)∈Cj[-1,1],0≤j≤5,则Cn(f,x)对f(x)的逼近程度均达到最佳。即|Cn(f,x)-f(x)|=O1nj+1+1njωf(j),1n,(0≤j≤5).  相似文献   

6.
用半经验的紧束缚方法sp^3s^*计算了薄层应变超晶格(InxGa1-xAs)n/(GaAs)n(001)的电子结构。给出了组份X为0.53的超晶格(InxGa1-xAs)n/(GaAs)n的带隙值随层厚n的变化关系,以及超晶格(InxGa1-xAs)12/(GaAs)12的带隙值随组份X的变化关系。在得到超昌格能量本征值和本征函数的基础上,计算了该晶格系统的光学介电函数虚部,并与体材料GaAs和  相似文献   

7.
记B是由1,2,…,n的循环排列组成的集合,A_3(n)=maxmin(a_(i+1)+a_(i+2)+a_(i+3)),其中i=0,1,2,….n-1,a_(n+1)=a_1,a_(n+2)=a_2;ai取1.2,…,n中的任意值,i=1,2,…,n.本文讨论了A_3(n)的上界:除n=3,5.6外,当3|n-1时,A3(n)≤ ;当3|n时,A3(n)≤ ;当3|n+1时.A_3(n)≤.  相似文献   

8.
以修正的Jacobi多项式算子的零点作为插值的节点,构造了一个“1/16”平均插值过程Cn(f,x).若f(x)∈Cj[-1,1],0≤j≤3,则Cn(f,x)对f(x)的逼近程度达到最佳,结论为|Cn(f,x)-f(x)|=O1nj+1+1njωf(j),1n(0≤j≤3)|Cn(f,x)-f(x)|=Oωφλf,1nδn(x)1-λ(0≤λ≤1)  相似文献   

9.
讨论了图G-v与G-e的星色数的一些基本性质,得到了一些不等式和等式,给出等式x(G)=X(G)成立的图G的一个特征,并进一步证明了X(W2n+1)=X(W2n+j1)=4从而回答了A.Vince提出的某些问题。  相似文献   

10.
设a≤b是整数,G=(V(G),E(G)是一个图。G的一个支撑子图F称为G的一个[a,b]-因子,若对任意的υ∈V(G)有a≤dF(υ)≤b,图G称为是[a,b]-覆盖图,若对G的每一条边,存在G的一个[a,b]-因子包含它。本文给出了一个图的[a,b]-覆盖图的关于领域并的充分条件,得到了下列结果:设1≤a〈b是整数,G是一个阶为n的图,最小度δ(G)≥α且n≥2(a+b)(a+b-1)1/b如  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
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   

15.
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   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
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   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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