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1.
关于LD*设计的一个递归定理   总被引:2,自引:0,他引:2  
本文给出了三D~*设计的一个递归构造,证明了如下结论:X为n元集,I_v=[0,v],且存在LD~*[X]={L_1~1,L_1~2,L_x;x∈X}和LD~*[I_v]={L_2~1,L_2~2,L_i;i∈I_v},若满足条件:(i_0,i_1,i_2,i_3)∈L_2~1当且仅当(i_1,i_0,i_2,i_3)∈L_2~2,则存在LD~*[X×I_v]。  相似文献   

2.
提出了完全分配元的概念,证明了:(1)在 CMP 范畴中,L∈ob(CMP)上的自由分子格恰是由 L 的完全分配元构成的 L 的子偏序集 C(L).(2)在 CMP′范畴中,L∈ob(CMP′)上的自由 F 格恰是 C(L)赋予某种逆合对应所得到的格,  相似文献   

3.
可补格按恒Ⅰ式集分类的问题(Ⅱ)   总被引:1,自引:1,他引:0  
本文是[1]的续篇。关于问题的含义以及有关概念与结果,都请参看该文,这里不再重复。本文讨论一种称为分组格的特殊可补格,得到了关于分组格按同型关系分类的一些初步结果。设 L 为一可补格,若存在 n 个子可补格 L_1,…,L_n 适合:(i)每一 L_i都含有0、I 以外的元。  相似文献   

4.
在本文中(L,≤,∨,∧,,)表示一个Fuzzy格,即具有逆序对合对应的完全分配格,这个格的最大元与最小元分别用1与0表示,I表示通常的单位区间[0,1],以及I(L)表示L不分明单位区间,在其上总取标准拓扑,记作τ,命L~b={α∈L|若α<β与α<γ,则α<(β∧γ)}S.E.Rodabaugh在[3]中讨论了不分明拓扑学中的连通性,证明了当ο∈L~b时(I(L),τ)是连通的,本文将在这基础上继续这方面的工作,讨论不分明拓扑中  相似文献   

5.
1 几乎连续、几乎开(闭)序同态的特征性质定义1 设f:(L_1(M_1),δ_1)→(L_2(M_2),δ_2)是序同态,a∈M_1,若Q∈η_2(f(a)),f~(-1)(Q°~-)∈η_1(a),(其中η_1(a)表示口的一切远域之集),则称f在分子a处几乎连续。定义2 设L(M)是拓扑分子格,S={S(n),n∈D}是分子网,a∈M,S叫做几乎收敛于a,若P∈μ(a),S(n)不≤P°~-最终成立。  相似文献   

6.
本文证明了以下结果:定理1 设f(z)是整函数,级λ< ∞,并且具有k个判别的级<1/4的渐近整函数,a_i(z)(i=1,2,...,k),L_i是相应的渐过路径对,D_i是相邻的L_i和L_(i 1)(L_(k 1)=L_1)界囿的单连通区域,再假设k=2λ,则在D_i(i=1,2,...,k)内存在一条连续伸展到∞的曲线F_i(i=1,2,...,k),使得(?)loglog|f(z)|/log|z|=λ;定理2 在定理1的假设条件之下,f(z)不具有级<λ的亏整函数.  相似文献   

7.
记f -=f1×f2×…×fn,N -n={1,2,…,n},=X1×X2×…×Xn,本文给出了f -是拓扑遍历的两个充要条件.若fi有POTP,Xi是连通的,i∈N -n,则f -是拓扑遍历的27个等价条件被给出.讨论了f -是拓扑遍历的一些充分条件和必要条件.设fi∈C0(Xi,Xi),Xi为紧度量空间,i∈N -n,证明了:①若f -是拓扑遍历的,则f ~1×…×f ~n∶ M(X1)×…×M(Xn)→M(X1)×…×M(Xn)是拓扑遍历的.②设(X∞(j), f∞(j))为由{Xi(j),gi(j), fi(j)}∞i=1生成的逆极限系统,j∈N -n,则f∞(1)×…×f∞(n)为拓扑遍历的当且仅当∏nj=1fi(j)(i=1,2,…)均为拓扑遍历的.③若存在j∈N -n,使得对t∈N -n且t≠j, ft均为拓扑混合的,则f -是拓扑遍历的当且仅当fj是拓扑遍历的.  相似文献   

8.
对任意一族具有小元的dcpo{Li}i∈I,证明了若每个σ(Li)是连续格,则ⅡLi上的Scott拓扑恰是诸Scott拓扑σ(Li)的积拓扑,得到了关于连续函数way-below关系的一些结果。  相似文献   

9.
基于Hilbert空间H上的一个完全分配可交换子空间格代数Alg L,考虑Alg L上的中心化映射.设为Alg L上的一个可加映射,用完全分配可交换子空间格代数的结构性质和代数分解,证明了:若存在正整数m,n≥1,使得A∈Alg L,(Am+n+1)-Am(A)An∈F I成立,则存在Alg L中心里的元素λ,满足A∈Alg L,有(A)=λA.  相似文献   

10.
本文讨论可补格的一种分类问题,它是由于考虑多值逻辑的判定问题而引起的。(正文中谈到了问题的逻辑来源。) 一个具有最小元O及最大元I的格L,如果在其中又定义了一个单值的1元运算“′”能适合O′=I,I′’=O,则称L为一可补格,一个命题演算良构式A(设只含命题连接词A,V,~),如果命它的变数在L中任意取值且将A,V,~分别解释为L中的运算∩,U,′时,A永远得到值I,则称A为L上的恒I式,当两个可补格L_1,L_2上的恒I式集相同时,称L_1,L_2为同型的,本文就是讨论可补格按同型关系分类的问题,所得结果如下: 定理设有限可补格L_2适合条件:(C),存在一良构式A(x,y)能使则任一可补格L_1与L_2同型的一个充分必要条件是: (A_1).存在一个由L_1的子可补格到L_2上的同态对应φ,并且, (A_2).对L_1中每一ξ≠I,都存在一个由L_1到L_2内的同态对应φ_ξ能使φ_ξ(ξ)≠I。  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
The non-orthogonal localized molecular orbital(NOLMO)is the most localized representation of electronic degrees of freedom.As such,NOLMOs are thus potentially the most efficient for linear scaling calculations of electronic structures for large systems.However,direct ab initio calculations with NOLMO have not been fully implemented and widely used,partly because of the slow convergence issue in the optimization of NOLMO.We devel-  相似文献   

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