一个支持任务动态调度和进程迁移的PC机群并行计算系统

介绍一个基于任务排队的能够动态调度并行任务且具有进程迁移功能的PC机群并行计算环境.     

一种基于扩展主题图的分布式知识融合

针对知识融合的效率问题, 扩展了传统主题图的组织结构, 并在此基础上构建一种基于扩展主题图的分布式知识融合体系结构, 提出一种基于全信息的主题图相似度算法, 设计了扩展主题图融合的规则和算法, 充分考虑了比较元素的涵义和所处语境, 提高了相似度算法的准确性, 实现了分布式环境下知识的有效融合.     

基于整数小波变换和差值扩展的可逆数据隐藏

针对传统差值扩展嵌入算法存在过分修改像素值、须嵌入溢出定位图等缺点,提出了一种基于整数CDF(2,2)双正交小波变换和差值扩展的彩色图像可逆数据隐藏算法.该算法用较小的差值扩展量扩展1个色彩分量的像素值,扩展方向由溢出像素的数量决定,采用调整像素值的方法避免像素溢出,并用少量的调整信息代替定位图,从而提高嵌入容量.提取端根据临界像素值的顺序定位调整的像素,用调整信息恢复调整像素的值,提取信息的同时可无损地恢复原始图像.实验结果表明:算法的整体性能优于预测误差差值扩展和传统差值扩展算法.     

分簇结构模调度框架研究

构建了面向分簇体系结构的模调度编译框架.介绍了分簇结构和支持向量化执行的体系结构的机器资源描述方法,研究了模调度和循环展开的关系,并给出循环展开的有效性条件判断,提出了向量化体系结构下模变量扩展算法框架,有效解决该体系结构下模调度的代码生成问题.实验结果表明,提出的面向分簇向量化体系结构的模调度编译框架,可以大幅提升程序循环部分的性能,加速比为170%~680%.     

基于图文法的可重构机床配置规划方法

为提高制造系统的快速结构配置规划响应速度,提出了基于图文法的可重构机床配置规划方法.使用图文法直观而形像地刻画动态体系结构的配置行为,利用基于图文法的平行模块配置技术,实现了体系结构图模型在具体系统配置规划中的物理实施,并使得图文法模型的图转换操作可以自动映射到实际配置系统的动态配置上.全面表达了可重构机床在配置规划中的相关特征和目标任务的对应变化,实现了平行模块配置规划技术.通过实例验证了该方法.     

动态图上的最短路径距离并行算法

设计动态图上最短路径距离查询的并行计算框架。通过构建增量图的方法, 实现一个批次内的多个查询在不同数据图版本的多线程并发执行。对于每个查询, 使用双向宽度优先搜索算法来减少搜索空间, 并提出搜索过程中扩展方向的决策函数。利用BSR对数据图邻接表进行编码, 结合 SIMD指令和图顶点重标号算法, 进一步提升数据级并行度。在真实图数据集下的大量实验验证了所提方法的高效性。     

润扬长江大桥结构损伤预警系统的设计与实现

研究了润扬长江大桥结构损伤预警系统的功能、体系结构、数据库和应用软件的设计与实现方法.提出了结构损伤预警系统的两级架构设计和两阶段实现方法,以保证结构损伤预警的实时性和准确性.建议采用Client/Server和扩展Browser/Server两种系统模式相结合的形式将结构健康监测系统与损伤预警系统相互结合,并采用MIMOSA数据库规范进行损伤预警数据库的设计.针对基于扩展Browser/Server模式的损伤预警软件特点,提出分别采用ActiveX技术和ASP技术实现客户端和服务器端应用的软件设计方法,并在此基础上编制了润扬长江大桥结构损伤预警系统软件.     

关于MIMD系统的并行处理——并行任务的识别

本文提供了一个用户程序的并行任务的自动识别方法,主要是引进了父进程与祖先进程以描述并行性的概念,引进了进程流程图以建立我们的并行程序模型,提出了一个并行处理图式用以自动地实现并行任务的识别与调度.     

轮扩展图的电阻距离及Kirchhoff指数

对于一些复杂图来说,计算其电阻距离非常困难.定义了一类新的图运算:轮扩展图.通过此类图的Laplacian矩阵和Laplacian矩阵的广义逆,给出了轮扩展图中任意两点之间的电阻距离和轮扩展图的Kirchhoff指数表达公式.用Matlab编程计算了此类图任意两点之间具体的电阻距离值及Kirchhoff指数.     

基于变量相关性分解方法的稀疏线性方程组并行求解算法

稀疏线性方程组的求解是许多大规模科学计算任务的核心环节。目前,并行算法的发展为稀疏线性方程组的求解提供了新的思路和强有力的工具。然而,现有的并行算法存在一些缺陷,如最优子矩阵的划分难以获得、并行任务间的同步开销较大等。针对上述问题,该文提出一种基于变量相关性分解方法的稀疏线性方程组并行求解算法。该算法首先对系数矩阵进行不完全LU分解,得到上三角和下三角方程组,然后在这2个方程组求解过程中利用y与x的关系分解变量的相关性,同时并行计算变量的独立部分值,最后将所有的独立部分值相加得到变量的最终值。由于算法中变量的求解无需等待其所有前继变量计算完成即可进行部分值计算,因此有效减少了算法的执行时间,进而提高了算法的求解速度及并行度。实验结果表明:与调用cusparse库函数实现的并行求解方法相比,该文提出的算法能将稀疏线性方程组的求解速度提升了50%以上。     

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…     

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。     

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     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

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.     

An improved R-tree based on childnode''s probability

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).     

Integrating GIS Web services based on mediating architecture

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.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

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.