首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
f(z)是一个亚纯函数,g(z)是f(z)的一个齐次微分多项式且f(z)与g(z)有相同的级。方程f(z)=0,f(z)=∞,g(z)=1的根分布在射线束;re~(iω)_1,re~(i(?))_1,…re~(iω)_(?)(r≥0,q≥1)上,并且δ(0,f)+δ(∞,f)+δ(1,g)>0。则f的级ρ必是有穷的,且 ρ≤β=sup{π/ω_2-ω_1,π/ω_3-ω_2,…,π/ω_(q+1)-ω_q} [ωq+1=2π+ω_1]  相似文献   

2.
在Harrison意义下的无界报酬函数折扣模型下,本文讨论了最优策略的几个性质和它的结构。本文证明了:若π~*=(π_1~*,π_2~*,…)是该模型的最优策略,则π_1~(*∞),(π_1~*,…,π_n~*)~∞与(π_1~*,…,π_n~*,π_1~*,π_2~*,…)(n≥1)都是最优策略;给出π_n~*也构成最优随机平稳策略的条件和修改方法;策略π~*=(π_1~*,π_2~*,…)是最优的当且仅当它在任何时刻可达的状态上都必须选取最优决策;最后指出π_0~(*∞)为最优随机平稳策略的充要条件是决策规则π_0~*是若干个最优平稳策略f_n~∞的决策函数f_n的凸组合。从而较完满地解决了Harrison无界报酬意义下折扣模型的最优策略结构问题。  相似文献   

3.
§1.設ξ_1,ξ_2是兩个相互独立的或然变量,F_1(x),F_2(x)是它們的分布函数;且設ξ=ξ_1+ξ_2,ξ的分布函数为F(x).如果ξ_11的分布与ξ_2的分布皆是正态分布,显然ξ的分布也是正态分布.反过来,如果ξ的分布是正态分布是否可以推出ξ_1的分布与ξ_2的分布也是正态分布呢?这个問題會为P.Levy考虑过,P.Levy断言如ξ的分布是正态分布,ξ_1的分布与ξ_2的分布也必須是正态分布,  相似文献   

4.
设π=(d_1,d_2,…,d_n)是非负整数序列,π_1,π_2是将π的所有元素划分为两部分后的两个子序列.如果-1≤|π_1|-|π_2|≤1,则称π_1,π_2是π的一个平衡二部划分,其中|π_i|(i=1,2)表示π_i中的元素数目.设k和n是两个正整数,π=(k~n)是k-正则可图序列.本文确定了ψ_(max)(π)的值和ψ_(min)(π)的值.  相似文献   

5.
设函数f(x)∈L(0,2π)是以2π为周期的周期函数,它的福里哀级数是 sum from 0 to ∞ (A_n(x))≡1/2α_0 sum from 1 to ∞ (α_ncosnx b_nsinnx) 固定x,瓦虚尼[1]证明了:当函数  相似文献   

6.
<正> 具有密度函数f(x)=1/π·λ/(λ~2(x-μ)~2)的连续型随机变量称为服从柯西分布的随和变量,尽管这种随和变量的各阶矩都不存在,也不服从中心极限定理,然而它却有着许多良好的性质。众所周知,若ξ_1、ξ_2、……ξ_n 为任意n 个相互独立的柯西型随机变量,则它们的线性组合η=α_1ξ_1+α_2ξ_2+……+α_nξ_n 仍然服从柯西分布,即具有再生性。本文要指出,利用柯西分布与均匀分布的密切联系,可推得柯西分布的另一种复杂得多的组合分布仍然服从柯西分布。定义称μ=0,λ=1时的柯西分布为标准柯西分布。定理若随机变量ξ服从标准柯西分布,则随机变量  相似文献   

7.
本文根据R·P·Feynman量子力学路径积分方法,求得了偶极近似下单模场与二能级原子系统相作用的传播函数。当传播函数具有最大值时,得到入射光与受激辐射光的量子相位关系Φ_2-Φ_1=2nπ,(n=0,±1,±2,…)与相干光条件一致。  相似文献   

8.
§1.引言用 C_(2n×2n)表示对每个变元均以2π为周期的二元连续函数空间,其范数为‖f‖_c=■|f(x,y)|。函数类 H~(ω_1,ω_2)。由 C_(2n×2n)中满足下述条件的函数 f(x,y)组成  相似文献   

9.
本文讨论了平面有界区域上,散度形式的二阶椭圆型方程的Dirichlet问题:■的弱解的全局Hlder估计。其中,α~(if)(x)是Ω上的有界可测函数,且满足■对一切x∈Ω,ξ=(ζ1,ξ2)∈R~2成立;λ_1>0,λ=λ_1/λ_2。本文证明了(1)、(2)的解u∈W~(1.2)(Ω)∩C°■在φ∈C~β(■Ω)和边界满足适当条件时,可以有βrπ/2(2π-α)(r<1/2(1 λ)λ~(1/2),0≤α≤π)的全局Hlder连续性,比K. O. Widman 1969年两种情况的结果都好。  相似文献   

10.
缺项整函数的奇异方向的分布   总被引:2,自引:2,他引:0  
本文着重讨论缺项整函数的Julia方向和Borel方向的分布,并获致以下两个有趣的结果。定理1.设f(Z)=∑C_nZ~(λn)为一整函数,且满足缺项条件:■ (A)则对于任一条从原点出发的半直线J:arg z=θ_0(0≤θ_0<2π),或者J:arg z=θ_0为f(z)的Julia方向;或者存在正数ε(θ_0),使得■ (B) 定理2.设f(z)=∑C_nZ~(λn)为一满足缺项条件(A)的正规增长整函数。若f(z)的级λ为正数或无穷大,则对于任一条从原点出发的半直线B:arg z=θ_0(0≤θ_0<2π),或者B:arg z=θ_0为f(z)的Borel方向;或者存在一正数ε(θ_0)及集合E满足lim mes(E(z;|z|≥r))=0,使得■ (C)  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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号