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.
研究有界区域内一类具有对数非线性项的伪抛物方程的齐次Dirichlet初值问题.分别在低初始能量0J(u_0)d和临界初始能量J(u_0)=d条件下,研究了问题的弱解的整体存在性.此外,在适当假设下,得到了问题的弱解的唯一性及其在有限时间内发生爆破的结果.  相似文献   

2.
考虑如下具有记忆项的非线性Petrovsky方程:utt+Δ~2u-∫t0g(t-τ)Δ~2 u(x,τ)dτ+︱u_t︱~(q-2) ut=︱u︱~( p-2) u,具Dirichlet边界条件的初边值问题。当松弛函数g满足适当的条件时,该问题的解在有限时间内会爆破。进一步对解的爆破时间进行研究,给出了正的初始能量下解的爆破时间的下界估计。  相似文献   

3.
讨论了一类带记忆项的双曲型的阻尼波动方程解的能量衰减估计问题.此类方程的损耗十分微弱,且包含在记忆项中.利用乘子思想,构造等价于能量函数E(t)的Lyapunov函数L并利用微分不等式来得到相应的解的能量衰减估计.  相似文献   

4.
在黄头 (Motacillacitreola)自然生长状态下 ,通过测定雏鸟气体代谢和身体组织能量积累的方法 ,研究了它们在生长期间的能量投入 .最小能量投入在 0~ 1d (d为日龄 ,用t表示 ) ,为 10 82kJ/d . 1只雏鸟需要能量为 414 2 6kJ,其中生产能为 15 3 14kJ,用于维持的能量是 2 6 1 12kJ .  相似文献   

5.
本文证明了在某些条件下,确定耦合的双曲-抛物方程组低阶项系数的反问题(带有Dirichlet-Cauchy数据)在H~5空间内存在有唯一的解。主要的工具是能量不等式。  相似文献   

6.
本文证明了在某些条件下,确定耦合的双曲-抛物方程组低阶项系数的反问题(带有Dirichlet-Cauchy数据)在H~8空间内存在有唯一的解。主要的工具是能量不等式。  相似文献   

7.
图的匹配能量定义为该图的匹配多项式的零点的绝对值之和.设U(n,d)为n阶且直径为d的连通单圈图的集合,刻画了U(n,d)中取到极小匹配能量的极图.  相似文献   

8.
在UB3L YP/6-311 G(d,P)、UB3L YP/6-311 G(3df,2p)、UB3L YP/AUG-CC-PVTZ,UQCISD/6-311 G(d,p)水平优化得到了N2S2单、三重态的平衡几何构型,发现单重态N2S2为能量最低的稳定分子。用优化的最稳定单重态N2S2结构在UB3L YP/6-311 G(d,p)//UB3L YP/6-311 G(d,P),UB3L YP/6-311 G(3df,2p)//UB3L YP/6-311 G(3df,2p)计算同键反应芳香性稳定化能(HASE)。用基团加和法(group increment approach)在UB3L YP/6-311 G(d,P)//UB3L YP/6-311 G(d,P)和UB3L YP/6-311 G(3df,2p)//UB3L YP/6-311 G(3df,2p)水平计算磁化率增量(A),计算结果表明N2S2分子的键长发生了平均化。同键反应芳香性稳定化能和磁化率增量均为负值.表明N2S2具有芳香性.实现了N2S2分子芳香性的几何、能量和磁性的判定.  相似文献   

9.
在黄头Ji Lin(Motacilla citreda)生长状态下,通过测定雏鸟气体代谢和身体组织能量积累的方法,研究了它们在生长期间的能量投入,最小能量投入在0-1d(d为日龄,用t表示),为10.82kJ/d,1只雏鸟需要能量为414.26kJ,其中生产能为153.14kJ,用于维持的能量是261.12kJ。  相似文献   

10.
我们在无机化学和结构化学的学习中,经常遇到这样的问题:3d和4s轨道的能量到底哪一个高?电子在填充这些轨道时,遵循什么规律,按照什么顺序?电离时首先失去的是哪个轨道上的电子?这些问题,现有的新版高校教材都没有予以圆满地、系统的阐述.目前,国内外的一些化学工作者都在积极地探讨这些问题.本文试从量子力学的基本假设出发,推出3d和4s轨道的能量计算公式,借助于斯莱特(Slatar)规则定量地计算出1~36号元素原子的3d和4s轨道能量,同时也计算了电子在这些轨道上排布时各种可能组态的能量,从而在解释上述问题时得到了比较满意的结果.  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.
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   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  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