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1.
证明了当 f∈PWπ时 ,‖s(k)2mf - f(k) ‖ Lp(R) → 0 (m→∞ ,2≤p≤∞ ,k =0 ,1,2 ,… ) ,其中PWπ是经典的Paley Wiener类 ,s2mf是在实Riesz基序列上对 f插值的唯一确定 2m - 1次缓增样条 .同时还证明了当 { f(tj) }∈l2 ,f∈Lp(R) (p≥ 2 ) ,‖s2mf‖2 ≤A一致成立时 ,若limm→∞ ‖f -s2mf‖ p=0 ,则 f∈Bπ ,p,其中Bπ ,p为指数π型整函数在R上的限制与Lp(R)的交  相似文献   

2.
等距节点下三次样条函数的误差估计   总被引:1,自引:0,他引:1  
样条插值函数的余项估计是样条函数逼近的基本问题之一,假设函数f(x)是足够光滑的,即满足对f(x)的高阶导数的要求,对f(x)的余项R(x)利用泰勒展开式及积分表达式,分析其特性,运用一些变换技巧,而得到余项R(x)的估计式,并给出了误差限,同时还可以对余项的导数R(i)(x)(i=1,2,3)进行估计。  相似文献   

3.
设 是区间[0,1]的一列分划;sp(3,△R)是对于分划△R 的三次样条函数空间,即若s(x),则s (x)i=0,1,…,NR-1;且 s(x)[0,1].记 对干连续函数[0,1] ,在sp(3,△k)中构造它的插值样条s(x),常见的三种,即三次周期型插值样条(若f(0)=f(1)的话)、三次自然型插值样条,(在[1]中称为(Ⅱ’)型插值样条)和三次(Ⅰ’)型插值样条(见[1] p94)。这三种样条在[2]中分别用插值算子L△Kf,N△Kf和S△Kf来表示,它们都是线性、幂等因而是投影算子。 I.J.Schoenberg[3] 曾提出过这样的问题:对于满足△k→0的分划列△R,是否对[0,1]上的一切连续函数f都有P△Kf-f…  相似文献   

4.
证明了当f∈PWπ时,‖ s2m^(k)f-f^(k)‖Lp(R)→0(m→∞,2≤p≤∞,k=0,1,2,…)其中PWπ是经典的Paley-Wiener类,s2mf是在实Riesz基序列上对f插值的唯一确定2m-1次缓增样条,同时还证明了当{f(ti)}∈ι2,f∈Lp(R)(p≥2),‖s2mf‖2≤A一致成立时,若lin/m→∞‖f-s2mf‖p=0,则f∈Bπ,p,其中Bπ,p为指数π型整函数R上的限制与 Lp(R)的交。  相似文献   

5.
设K是一个域,一个超曲面f(x1,x2,…,xn)=0的坐标环是K[x1,…xn]/f,令R=K[x1,…,xn-1],则K[x1,…,xn]=R[xn].坐标环为R[xn]/f.根据Hilberx合冲定理,R[xn]的整体同调维数是n.本文中假设R是一个有单位元的交换环,f是R上的一个多项式,A=R[x]/(f).我们定义了一个(R,k)-多项式,它是首一多项式的推广,即当k=0时,它是环R上的一个首一多项式.本文的主要结果是当f是(R,k)-多项式时,A是忠实平坦的R-模,并且当A的同调维数为有限时,其整体同调维数满足GD(A)≤GD(R)≤GD(A)+pdR(A)≤GD(A)+1,这里我们认为R的同调维数是有限的.  相似文献   

6.
把线段连续自映射混沌集合的Hausdorff维数的有关结论推广到I2上,证明了在C °(I2)中存在一个剩余集R,使对每一f∈R,如果集合CI2对f是Li-Yorke混沌的,则C的Hausdorff维数dimH (C)≤1.  相似文献   

7.
给出了在非均匀节点情形下用任意k阶B样条作为基函数构造具有高次局部多项式再生性质拟插值的一种方法,并用此方法构造出在无限区间R上具有k-1次多项式再生和k阶收敛阶性质的高精度拟插值(㏑f)(x).进一步地,利用B样条的相关性质由(㏑f)(x)构造出有限区间[a,b]上的高精度拟插值(㏑f)(x).作为数值例子,最后用4阶B样条构造的高精度拟插值(㏑f)(x)逼近一些典型函数以说明其确实具有高精度逼近性质.  相似文献   

8.
探讨了交换环上上三角矩阵空间、对称矩阵空间以及全矩阵空间中保持行列式的函数.证明了如下结论:1)设f是交换环R到自身的一个映射,n(n≥2)是一个整数,则下列条件等价:①f是R上n阶上三角矩阵空间中保持行列式的函数;②f=f(1)δ,其中f(0)=0,f(1)n=f(1),δ满足δ(xy)=δ(x)δ(y).2)设f是交换环R到自身的一个映射,n(n≥3)是一个整数,则下列条件等价:①f是R上n阶对称矩阵空间中保持行列式的函数;②f是R上n阶全矩阵空间中保持行列式的函数;③f=f(1)δ,其中f(1)n=f(1),δ是R上的非零自同态.  相似文献   

9.
利用R(L)型诱导拓扑空间的概念,证明了R(L)型诱导拓扑空间(R(L)X,ω(δ))是C1,C2可数的和准lindelёf空间当且仅当拓扑空间(LX,δ)是C1,C2可数的和准lindelёf空间,即可数性是R(L)的良好推广.  相似文献   

10.
主要证明了以下定理:设f是超越整函数,R是非常数有理函数,k、m是两个不同的正整数,d=(k,m)是k、m的最大公约数.若f,f(k)f(m)CM分担R,那么f=f(d).  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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
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   

19.
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   

20.
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   

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