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1.
关于拟阵的基,G·C·Rota 1989年提出了一个对于某个秩为n的拟阵的n个基的猜想,简称Rota猜想.本文对这个猜想作了进一步的研究.由于相关文献主要集中在对n的讨论上,本文从另外一个角度讨论了特殊矩阵关于Rota猜想的情况,同时还提出了一个关于线性空间的类似于Rota猜想的推论.  相似文献   

2.
粗糙拟阵是同时推广了粗糙集和拟阵的数学工具,它既可以被理解为是借助拟阵研究粗糙集,也可以被当作是通过粗糙集来研究拟阵.粗糙拟阵能够利用粗糙集和拟阵各自的优势处理和分析数据.通过等价关系上可定义集的性质,研究了基于等价关系的上粗糙拟阵和下粗糙拟阵.事实上,基于等价关系的上粗糙拟阵同时也是基于这个等价关系的下粗糙拟阵.因此给出了基于等价关系的粗糙拟阵的概念.类比拟阵中基的概念,定义了基于等价关系的粗糙拟阵的基,并且研究了这些基的性质.根据基的性质得到一个论域上所有的粗糙拟阵.特别地,讨论了论域的任何一个子集与该论域上的粗糙拟阵之间的某种对应关系.  相似文献   

3.
讨论了基图与欧图的关系,并给出了拟阵基图是欧拉图的充分条件,然后又证明了拟阵基图为欧拉图的一个充分必要条件。  相似文献   

4.
Welsh猜想:按平均计算,一个拟阵的圈的数目少于基的数目。Quirk和Seymour证明了:若M是简单图的圈拟阵,则b(M)≥c(M),其中b(M),c(M)分别表示M的基与圈的数目。本文证明:若M是至多含有一个2—圈的无环图的圈拟阵,则b(M)≥c(M) 1。从而改进并推广了Quirk和Seymour的结果。  相似文献   

5.
闭正规模糊拟阵的模糊基集特征   总被引:3,自引:3,他引:3  
通过对初等模糊拟阵的模糊基的讨论,找到了闭正规模糊拟阵的模糊基集的特征,这种正是拟阵的基公理在模糊拟阵中的推广。  相似文献   

6.
提出了拟阵的基关联矩阵概念,基于此给出了一个求秩的公式,以及一个矩阵是拟阵的基关联矩阵的充要条件.同时给出两个拟阵有K-公共独立集(基数为K的公共独立集)的另一充要条件,并与Edmonds交定理判定的复杂性进行了比较.  相似文献   

7.
关系粗糙拟阵的概念最早是由祝峰教授等人最先提出的,是作为一种同时推广了粗糙集和拟阵的概念.在他们工作的基础上,本文将进一步对关系粗糙拟阵的性质进行研究.首先,研究了基于关系的可定义集的一些性质.特别地,基于一个自反关系上的可定义集关于集合的包含运算作成一个格;其次,探究了关系粗糙拟阵的一些性质,并且给出了一些特殊关系粗糙拟阵的等价描述.  相似文献   

8.
准模糊图拟阵   总被引:8,自引:0,他引:8  
在作者前期工作的基础上继续讨论国圈好模糊拟阵的基础性质,给出圈好模糊拟阵的“模糊圈公理”;然后,研究了“基好模糊拟阵”及其与圈好模糊拟阵的等价性;最后,总结圈好模糊拟阵与“基好模糊拟阵”的性质,提出“准模糊糊图拟阵”的概念,证明了“准模糊图拟阵”的“模糊基公理”和导出拟阵序列特征。刻画了“准模糊图拟阵”的内在本质,提供了一种构造“准模糊图拟阵”的方法。  相似文献   

9.
根据传统拟阵的基交换定理,作者给出了闭正规模糊拟阵的基交换定理,得到了一系列结论,并在此基础上进一步研究了闭正规模糊拟阵的模糊基与模糊圈之间的关系,然后给出了闭正规模糊拟阵中某模糊独立集是模糊基、从一个模糊基得到一些模糊圈、以及从一个模糊圈得到一些模糊基的充要条件.  相似文献   

10.
若一个正整数m可表为正整数n与它的除数函数d(n)之商,则称m为优美指数.本文证明了,存在无穷多个正整数m不是优美指数,从而否定了A.Murthy的猜想,并提出了若干个关于非优美指数的猜想.  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 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   

13.
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   

14.
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   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
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   

18.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

19.
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   

20.
赵英华 《科技信息》2008,(12):219-220
0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation's behavior in their social life throughout the long history is beyond list.  相似文献   

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