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1.
给出判定函数是否一致连续的几个命题,主要有:若函数f(x)在区间[a,+∞)上连续,且当x→+∞时,f(x)有渐近线y=kx+b,则f(x)在[a,十∞)上一致连续;若函数f(x)是[a,+∞)上单调增加的可导函数,并且其图形在该区间上上凸,则f(x)在[a,+∞)上一致连续;若函数f(x)在区间[a,+∞)上可导,且,则f(x)在[a,+∞)上不一致连续.  相似文献   

2.
在没有基本假设∞↑∑↑n=1(kn-1)〈∞或∞↑∑↑n=1(kn^p-1)〈∞的前提下研究了一类具体的渐进非扩展映像的不动点迭代构造问题,获得了几个强收敛结果,其中p〉1为固定的实数,{kn}为渐进非扩展映像的渐进序列。  相似文献   

3.
本文证明了两端奇异的微分算子的Kodaira公式:若τ(y)是(-∞,∞)上定义的n阶微分算式,其在(-∞,0]上的亏指数为d ̄-,在[0,∞)上的亏指数为d ̄+,则τ(y)的亏指数d=d ̄-+d ̄+-n。  相似文献   

4.
对中立型微分差方程d[y(t)+Py(t-τ)]/dt+Q(t)y(t-σ)=0,其中P∈R,R∈(0,∞),σ∈[0,∞),Q∈([t0,∞),R^+),得到了其一切解振动的充分条件及非动解的渐近性质,其结果推广并改进了文献中的一些熟知定理。  相似文献   

5.
首先研究建立在任意域是上的A∞型路代数kA∞的有限维模范畴,给出了kA∞的有限维模范畴与A∞的有限子quiver所对应的路代数上的有限维模范畴之间的关系,特别的具体的给出了所有的不可分解有限维kA∞模,精确的刻画了不可分解模之间的模扩张;然后给定有限域k,研究了建立在有限维kA∞模范畴上的Ringel—Hall代数H(kA∞).证明了H(kA∞)恰好是当n趋向∞时H(kA∞)的正向极限,特别的找到了H(kAv)的一个PBW基,并且证明H(kA∞)恰好与它的合成子代数相符合.  相似文献   

6.
通过对广义二重积分F(α,β)=∫+∞-∞∫+∞-∞(αx+βy)λe-(x2+y2)dxdy作正交变换,得到它满足的函数方程,并求得该函数方程的一般解,进而导出对任意参数λ计算上述广义二重积分的基本定理。并将基本定理推广导出计算广义n重积分F(α1,α2,…,αn)=∫+∞-∞∫+∞-∞…∫+∞-∞(α1x1+α2x2+…+αnxn)λe-(x21+x22+…+x2n)dx1dx2…dxn的公式。  相似文献   

7.
运用留数定理求解形如∫^∞ -∞e^axf(e^x)dx的一类亚纯函数的广义积分及其Cauchy主值的和,得到∫^∞ -∞e^axf(e^x)dx(Cauchy主值)与留数间的关系.  相似文献   

8.
把空间L′[a,b]中集合列紧性的判别法推广到L^p(-∞,+∞)中,得到空间L^p(-∞,+∞)中集合列紧性的一个充要条件。  相似文献   

9.
整函数与基样条的关系   总被引:1,自引:1,他引:0  
主要结果是:对f∈L2(R),有limE(f,π/σ,m∩L2(R))2(R)=E(f,σ∩L2(R))2(R),且存在f0∈L∞(R),使得linE(f0,π/σ,m∩L∞(R))∞(R)>E(f0,σ∩L∞(R))∞(R),其中π/σ,m为m-1次的以{(1/2)jπσ-1(m+1)}j∈Z为节点的基样条的全体,σ表示指数σ型的整函数在R的限制的全体,其中σ>0。  相似文献   

10.
运用Lyapunov泛函方法,研究一类具有连续分布时滞模型x′i(t)=-bixi(t)+∑nj=1aijfj(μj∫t-∞kij(t-s)xj(s)ds)+Fi(t),τij∈[0,∞),i,j=1,2,…,n其平衡点的全局渐近稳定性,获得了一些新的充分条件.  相似文献   

11.
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   

12.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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