解线性互补问题的多分裂多松弛因子迭代算法

考虑矩阵的多重分裂与处理器的并行计算,提出了求解线性互补问题的多分裂多松弛参数迭代算法,利用M-矩阵和H-矩阵的性质及松弛迭代的收敛性,证明了算法产生的迭代点列的聚点为原互补问题的解。最后,为提高算法的收敛速度,分析了ILU分解预处理技术的收敛特性。     

解线性互补问题的非精确松弛多分裂算法

基于矩阵的非精确分裂和多重分裂、处理器的并行计算和松弛迭代算法,提出了求解线性互补问题的非精确松弛多分裂算法,当问题的系数矩阵为对角元为正的H-矩阵时或对称半正定时,证明了算法的全局收敛性.并在一定条件下给出了非精确松弛多分裂算法内迭代的特殊形式,分析了该情形下算法的收敛特性.     

求解一类非线性互补问题的广义模基矩阵分裂迭代法

通过引入新的正对角参数矩阵, 提出了求解$H$-矩阵非线性互补问题的广义模基矩阵分裂迭代法和广义二步模基矩阵分裂迭代法, 取定特殊的正对角参数矩阵和矩阵分裂后, 两种算法都可转化为已有的模基矩阵分裂迭代法, 因此是已有求解线性互补问题和非线性互补问题模基矩阵分裂迭代法的推广. 利用$H$-矩阵的相关性质建立了两种算法的收敛性分析, 在算法收敛的充分条件中, $H$-分裂的假设比已有的非线性互补问题模基矩阵分裂迭代法$H$-相容分裂的收敛条件更弱; 另外, 所得到的正对角参数矩阵的收敛域比已有非线性互补问题模基矩阵分裂迭代法的收敛域更大, 因此收敛性结果是已有算法收敛性结果的推广改进, 这表明新的正对角参数矩阵是有效的.     

线性互补问题的SSOR多分裂算法

运用矩阵的SSOR多分裂和松弛迭代算法,提出了一类求解线性互补问题的数值解法.在一定条件下分析了算法的全局收敛性和松弛因子的范围,扩大了以往求解线性方程组的SSOR多分裂迭代算法的收敛区域.     

解线性互补问题的多重分裂乘性Schwarz算法

运用矩阵多重分裂理论并考虑并行计算,建立求解线性互补问题的多重分裂乘性Schwarz迭代算法,给出算法的收敛性定理,应用加权最大模获得了算法的收敛速度．数值结果表明,多重分裂乘性Schwarz迭代算法具有很好的有效性．     

一般二次规划的一种分解算法

提出了求解一般二次规划问题的一种分解迭代算法.算法的主要思想是对问题的Hessian矩阵G进行正则分裂,即G=N H并且满足N-H是正定的.在每次迭代中用一个易于求解的矩阵N代替G进行计算.在矩阵G是正定的条件下,算法具有线性收敛性质,产生的迭代点列收敛到原问题的最优解.当矩阵G不正定时,算法产生的点列收敛到问题的稳定点.     

两步模系矩阵分裂算法求解弱非线性互补问题

考虑两步模系矩阵分裂算法求解弱非线性互补问题,理论分析给出了当系数矩阵为正定矩阵或H+-矩阵时迭代法的收敛性质和两步模系超松弛迭代法的参数选取范围.数值实验表明,两步模系矩阵分裂算法是行之有效的,并在迭代步数和迭代时间上均优于模系矩阵分裂算法.     

对称仿射二次锥互补问题的二级迭代算法

仿射二次锥互补问题是一类重要的均衡优化问题,包括线性互补问题、半定互补问题、非线性互补问题等。基于矩阵分裂,提出了求解对称仿射二次锥互补问题的一类迭代算法,给出了算法的全局收敛性。并在一定条件下分析了算法的收敛速度。     

求解分裂可行问题的一种新算法

主要对解决分裂可行问题的松驰CQ算法进行修正,设计了一种新的算法.该算法在每步迭代中应用类-Armijo搜索来获取步长,避免了矩阵逆和矩阵最大特征值的计算,而且在每步迭代中都根据当前迭代点的信息选择合适的步长,证明了该算法的全局收敛性.     

EAOR投影迭代算法求解一类对称双正型线性互补问题

研究求解一类对称双正型的线性互补问题的EAOR迭代算法．证明了由此算法产生的迭代序列的聚点是线性互补问题的解．并且，当互补问题中的矩阵为对称双正加阵或严格对称双正阵时，算法产生的迭代序列存在子序列收敛到互补问题的解．而当矩阵为非退化对称双正加阵时，该序列收敛．     

An Index mechanism for multi-scale view in spatial databases

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

A computer generator for randomly layered structures

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

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

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     

Advances in broadband wireless communications under high-mobility scenarios

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.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

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。     

Scale-based spatial data model for GIS

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.     

Exciton Seebeck in Molecular Systems

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     

Achieving Unusual States of Matter Under High Pressure

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