普通网格用户资源管理模型的进一步研究

从方便普通用户的角度出发,提出了一种以网格企业为管理域的网格资源管理模型.该模型以网格经济模型为基础,既可以实现资源使用计费问题,又可以实现管理域内的资源最优化分配,在一定程度上提高了系统的性能.对服务请求的网格企业间分配可以打破管理域的限制,进一步优化资源配置,提高处理能力和服务质量.简要介绍了基本的资源管理方式,对提出的普通用户资源管理模型的网格企业的内部管理方式、企业间资源交易进行了阐述,最后讨论了资源信息发布和需求信息发布两种方式的优缺点.     

网格计算环境中的资源管理研究

现有的资源管理模型往往无法同时满足网格计算的动态性、可伸缩性和适应性需求.针对这个问题,提出了一种融合了Web计算技术、正统的网格计算技术和对等计算技术的资源管理模型.它将整个网格计算环境分为两级,在各个管理域内部可采用不同的管理策略和体系结构,体现了对遗留系统的适应性支持;各管理域之间的组织则采用对等计算模式,从而可适应网格计算环境的动态性和可伸缩性.在该模型中,标准化的互操作性通过万维网服务提供,以克服资源的异质性;动态资源部署采用基于XML的数据模型来描述资源信息,并通过软状态机制来解决分布式垃圾收集问题;动态资源发现克服了LDAP和关系性数据模型的限制,具有高度的灵活性和可扩展性.     

面向密集数据处理的网格平台研究

针对网格环境下的密集数据处理,构建了网格平台IDPGP.该平台基于Globus Toolkit 4、OGSA-DAI、Condor和PBS,主要提供网格信息服务、网格资源管理、数据访问与集成等服务,实现网格资源共享,完成密集数据的读取与处理.在网格资源管理服务中设计了一个基于分层模型的计算资源管理模型,既保证了每个虚拟域的一致性和可管理性,又增强了整个平台的可扩展性和容错能力.     

基于ASP的制造网格资源发现模型

针对制造网格应用上的困难,基于应用服务提供商(ASP)模式,提出了基于多区域多层次树型覆盖网络的ASP平台分布的制造网格资源发现模型,在此基础上提出了自动在线组建机制及其波浪推进式的信息更新算法,剖析了模型的ASP应用模式的本质,进而给出了资源发现机制及其实现算法.与传统的典型资源发现相关模型相比,该模型在资源发现和资源更新方面更具优越性.文中还基于该资源发现模型,设计并实现了包括基于eUDDI注册中心的资源注册、资源发现、资源信息监控与动态维护以及信息交流等功能的企业信息节点原型系统.     

网格环境下一种基于招标的信任评估模型

为了提高信任模型中信任查找的效率和更有效的防止恶意推荐,对在网格环境下的信任模型引入了招标的思想以及改进了信任更新机制.首先由评估者向资源实体发出招标信息,资源实体根据招标信息投标或不投,评估者收到资源实体的投标申请书,就只需在已发投标申请的资源实体中进行信任查找,然后与符合条件的资源实体签订合约;在信任更新机制中将推荐行为发生后总体信任值作为较真实的信任值,与中间实体推荐信任值比较,根据二者的误差生成反馈,调整对此实体的信任度.实验表明信任模型在引入招标机制和改进了信任更新机制后,不仅调动了资源节点的主动性,实现了用户和资源的互动,提高了信任查找的效率,而且能够更好更有效的防止恶意推荐.     

基于分层结构和树型覆盖网络的网格资源发现模型

针对现有网格资源发现方法的不足,提出了一种基于分层结构和树型覆盖网络的网格资源发现模型.该模型将网格从逻辑上分成上下两层:下层由拥有各种网格资源和服务的网格资源节点组成;上层为网格信息节点组成的可靠分布树型覆盖网络,负责信息节点的组织、管理和资源定位.该模型以分层的方法来改进大规模分布网格环境资源发现的可扩展性,以可靠的树型覆盖网络来提高资源发现的效率,以并行方式来实现快速资源定位,以完全分布的方式组织信息节点来解决资源信息更新和维护问题.实验结果验证了所提出模型的有效性.     

网格环境下的资源信用模型

主要解决网格环境下动态资源的管理问题.首次提出了资源信用的概念,通过资源信用描述资源的可靠性和动态性.初步定义了影响网格资源信用的关键因素,给出了网格资源信用的简单计算方法.通过将资源信用模型嵌入资源调度系统,尽量将任务分配给信用值较好的资源以提高系统的可靠性.实验结果表明,引入资源信用模型后,网格系统的稳定性有了明显提高,说明网格资源信用模型是有效的.     

基于P2P结构的无线网格资源发现机制

针对无线网络的特殊环境,提出了一种基于P2P结构的无线网格资源发现机制,该机制结合了分布式与集中式网格资源发现的优点,引入了超级节点的概念,通过超级节点管理域内用户,将资源信息存放在超级节点中,避免了中央节点聚合目录的更新.并在此机制基础上给出了一个无线网格信息服务架构,满足了无线网格资源发现的分散性和可扩展性的特点.理论分析和实验证明能够提高无线网格资源发现效率.     

网格身份认证和细粒度访问控制模型的研究与设计

网格是继因特网(Internet)、万维网(Web)之后,互联网发展的第三个里程碑。网格系统具有数据量大、地理上分布、数据库结构异构、其应用环境网络化、用户人数众多、分散的特点。开放的网络环境对信息的传输没有足够的安全保证。网格系统的安全问题已经成为网格研究的热点问题,国内外研究机构正在对网格安全问题进行广泛的研究。身份认证和访问控制机制是网格安全的重要研究方面,产生了集中式层次认证模型、混合交叉认证模型等网络安全认证模型。这些方法都存在各种各样的缺陷,如证书管理复杂,路经选择困难,不能进行细粒度的访问控制等。探讨在网格环境中跨域身份认证和细粒度访问控制系统方面,提出了基于多种认证组合和资源代理的网格身份认证及访问控制模型,通过混合身份认证和票据交换达到身份认证的及时性、有效性和细粒度资源控制,在用户数量大、更新频繁的情况下,达到系统响应速度快的要求。     

基于拍卖和免疫优化的网格作业分配机制

基于微观经济学方法和群体智能算法,设计了一种网格作业分配机制.首先建立网格资源管理模型,然后对经典拍卖模型进行了改进,通过拍卖过程对网格资源定价;引入亲和度函数,通过抗体生成、选择、克隆扩展、免疫记忆、自适应变异和调整等操作,基于改进的免疫优化算法,寻找最佳作业分配方案,兼顾时限和成本.基于GridSim对该机制进行了仿真实现,与现有的两种作业分配机制进行了性能对比,结果表明该机制更优.     

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)

正~~     

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.