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1.
Chemotaxis-Growth系统的整体吸引子   总被引:1,自引:0,他引:1  
研究了具有Dirichlet边界条件的Chemotaxis-Growth系统解的长时间行为.证明了Chemotaxis-Growth系统的解在L2(Ω)×L2(Ω)和H01(Ω)×H01(Ω)上的整体有界性,得到系统在L2(Ω)×L2(Ω)中整体吸引子的存在性.  相似文献   

2.
本文证明了抛物方程组N的弱解u=(u_1,u_2,…,u_N∈L_2(O,T)_3W_2~1-(Ω))∩L∞(O,T;L_2(Ω))的梯度的有界性。  相似文献   

3.
带梯度项的发展P-Laplace方程解的耗竭   总被引:2,自引:0,他引:2  
考察带梯度项的发展p-Laplace方程的第一初边值问题 ut - div(|u|p- 2u) = - λ|u|α- 1u |u|β, x ∈Ω,t> 0,u = 0, x ∈Ω,t> 0,u(x,0) = u0(x), x ∈Ω,其中p > 2,λ,α和β为正常数,u0(x) ∈L∞(Ω) ∩W1,p0 (Ω).  众所周知,若方程不带梯度项,上述问题的解当且仅当0 < α< 1 时在有限时间内耗竭.本文的目的是研究方程右边正的梯度项是否会影响解的耗竭性.应用能量方法,我们给出了解在有限时间内耗竭的充分条件.  相似文献   

4.
考虑了一类退化抛物方程全局吸引子的正则性.当非线性项任意阶增长时,通过渐近先验估计方法和投影方法分别得到了这类方程在L2(Ω),L°(Ω),L2p-2(Ω)(p≥2)及H10’a(Ω)中全局吸引子的存在性.  相似文献   

5.
目的 讨论了L2(Ω,F,P)空间上投影映射与条件数学期望的等价性.方法 采用了逻辑推理的方法进行了证明.结果 证明了L2(Ω,F,P)空间上的投影映射就是条件数学期望E(ξ|R).结论 表明在L2(Ω,F,P)空间上,条件数学期望E(ξ|R)是唯一满足投影方程的投影映射.  相似文献   

6.
研究半线性椭圆边值问题{-Δu(x)=λa(x)uq+b(x)up,x∈Ωu(x)=0,x∈■Ω的正解的存在性.其中Ω是RN中的有界光滑区域.λ>0是参数,00},{x∈Ω:b(x)>0}的测度均大于零.  相似文献   

7.
利用核的分解技术和Fourier变换估计,得到了粗糙核带参数的抛物型Marcinkiewicz 积分μ(Ω)(f)的L2(Rn)有界性.作为应用得到了分别与Littlewood-Paley g(λ)函数和Lusin面积函数相应的参数型Marcinkiewicz函数μ(Ω),(λ)和μ(Ω),s的L2(Rn)有界性.  相似文献   

8.
基于R -T空间Vh×Wh H(div;Ω)×L2 (Ω) ,本文讨论了Sobolev方程 -div{α ut+b1 u}=f的初边值问题混合有限元方法的最大模误差估计 .得到了数值解在L∞( 0 ,T ;L∞(Ω) )模下的拟最优阶误差估计 (有限元空间指数k =0 )和最优阶误差估计 (有限元空间指数k≥ 1)以及在L∞( 0 ,T ;L∞(Ω) 2 )模下的拟最优阶误差估计 .  相似文献   

9.
基于R -T空间Vh×Wh H(div;Ω)×L2 (Ω) ,讨论了Sobolev方程-div{a ut b1 u}=f初边值问题混合有限元方法的收敛性 .得到了最优L2 模误差估计  相似文献   

10.
利用算子半群分解技巧得到了非线性可拉伸梁方程在L2(Ω)×H01(Ω)中指数吸引子的存在性.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
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   

15.
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   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
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   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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