伪黎曼流形的极小子流形与调和映射

本文讨论伪欧氏空间中位置向量 x 满足 △x=λx 的子流形,并把一些结论推广到伪黎曼流形之间的光滑映射。     

伪黎曼空间形式中完备类空子流形的余维数约化

设M~n为等距浸入到伪黎曼空间形式N_p~(n+p)(c)中的完备类空子流形,平均曲率H有界且具有平行单位平均曲率向量场.如果M~n的平均曲率H满足相应条件,证明了该子流形的余维数p-可约化的问题.     

Hilbert空间中严格伪压缩映射Mann迭代的一个收敛定理

设H是实Hilbert空间,K为H中的紧凸集,T:K→H为严格伪压缩映射,满足弱内向条件.本文给出的主要结论是:若{αn}为(0,1)中的数列满足控制条件∑∞n=1αn(1-αn)=∞,x1∈K,则Mann迭代序列{xn}强收敛于T的一个不动点,此结果改进了文献[1]的结论.     

Banach空间上广义正则值原像的性质

本文指出广义正则值推广了通常正则值的概念.首次引进两个Banach空间之间C1映射f的广义正则值y的原像S=f-1(y)上的一对指标M(x)和Mc(x),证明它们是连续的.同时,讨论f(x)=y有孤立解的充分条件,证明S=f-1(y)含X0的连通分支是一个维数为M(xo)的C1Banach子流形,由此得到大范围分析中构造Banach流形的一个原理.     

伪球面及其子流形的一些性质

(n+p)一维伪球面H~(n+p)(-a~2)是指具有负常数截面曲率-a~2的完备、单连通的双曲空间。近来已有一些文章讨论伪球面上子流形的性质。本文采用在黎曼流形中引入半对称度量联络的方法来研究H~(n+p)(-a~2)及其子流形,得到共形平坦子流形为全脐点的一个条件。     

高阶色散方程的柯西问题

主要研究了高阶色散方程ut+2j+1xu=j+1x(u2)+j-1x(ux2),j≥2,j∈N,x,t∈R的柯西问题.使用修正傅里叶限制范数方法和Strichartz估计以及修正Bourgain空间,证明了这个问题在修正的Sobolev空间H(s,1/2j)(s-j/2+3/4)上是局部适定的.使用迭代技巧,也证明了这个问题在H(s,w)(0w1/2j)中,对于任意的s∈R,流映射不是C2的.     

不动点集为P(6,2n+1)的对合

设(M,T)是一个带有光滑对合T的光滑闭流形,T在M上的不动点集为F={x|T(x)=x,x∈M},则F为M的闭子流形的不交并.证明了:当F=P(6,2n+1)(n为奇数)时,(M,T)协边于0.     

拟欧氏空间R_2~4中的类空曲面

给出2阶实对称矩阵(h=(hij))空间到C的Hopf变换L(h)与平均曲率向量H满足的条件,讨论了拟欧氏空间R42中的类空曲面的一些性质,并将Pinl关于Gauss映射的一个结果推广到拟欧氏空间R42上.     

球面上k-极值子流形的特征值问题

通过选取适当的测试函数,估计单位球空间S~(n+p)(n≥3)中n维闭的k-极值子流形(k≥1)M~n上Schrdinger型算子L=-Δ-k(2-1/p)(S-nH~2)的第一特征值的上界,并基于特征值给出子流形M~n的特征,其中H和S分别为M~n的平均曲率和第二基本型模长平方,Δ为M~n上的Laplace算子.     

局部对称伪黎曼δ-拼挤流形中的极大类空子流形

在子流形几何中,极小子流形的研究是一个热门课题,许多作者做了研究.伪黎曼流形在物理和数学上都具有重要的研究价值,自然伪黎曼流形中的极大子流形就成了大家所关注的对象.局部对称伪黎曼流形是伪黎曼空间型的推广.主要研究了局部对称伪黎曼δ-拼挤流形中的极大类空子流形,通过活动标架法对子流形的第二基本形式模长平方的Laplacian进行了计算,从而得到了这类子流形是全测地子流形的一个充分条件,推广了局部对称空间中全测地子流形的外围空间.     

Markedness and its Interpretation in Language Use

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Features of Women's language

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.     

Design and analysis of generic LBS application developing platform

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

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.     

A computer generator for randomly layered structures

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

低渗透非均质砂岩油藏启动压力梯度研究

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

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.