网络容灾系统的规划和实现

规划和实现了一种网络容灾系统,采用"本地数据中心+异地容灾备份中心"的系统架构,实现了网络容灾、数据容灾和应用容灾.整个系统具有很强的系统防护和灾难容忍能力,同时还改善了系统服务质量.经过实际应用,系统功能和性能均达到了网络容灾系统的要求,     

基于SAN存储模式的异地容灾系统

为了确保基于存储区域网络(Storage Area Network,SAN)的异地容灾系统在主系统发生意外灾难后实现同城异地的数据容灾,采用SAN作为数据存储模式,通过光纤通道将生产数据中心和备份数据中心连接起来,使用跨阵列磁盘镜像技术实现异地数据中心之间的备份和恢复.容灾系统是计算机系统安全的最后保障,适用于大多数中...     

一种远程容灾系统的设计与实现

设计和实现了一种异地容灾系统,系统采用本地冗余和异地冗余相结合,服务和存储相分离的结构,采用本地控制中心作为事件处理中心和数据转发的缓存。并且设计了一种动态的失效检测算法,算法综合考虑了消息的延迟、丢失、当前网络状况和当前系统状况,能够有效的降低误判率和加快服务自动恢复速度。测试表明该系统的数据恢复速度和服务切换速度有了明显的提高。实际应用中系统运行稳定,性能良好,达到了高级别容灾系统要求。     

一种远程容灾系统的设计与实现

设计和实现了一种异地容灾系统,系统采用本地冗余和异地冗余相结合,服务和存储相分离的结构,采用本地控制中心作为事件处理中心和数据转发的缓存。并且设计了一种动态的失效检测算法,算法综合考虑了消息的延迟、丢失、当前网络状况和当前系统状况,能够有效的降低误判率和加快服务自动恢复速度。测试表明该系统的数据恢复速度和服务切换速度有了明显的提高。实际应用中系统运行稳定,性能良好,达到了高级别容灾系统要求。     

一种异地容灾系统的状态监控方法

针对异地容灾系统提出了一种基于Internet的状态监控方法,即聚类时间触发状态监控方法.该方法能很好地将各种监控对象进行整合,可有效地对各个监控对象的运行状态进行实时监控,并可对状态监控数据进行提取和分析.该方法能很好地适应异地容灾系统结构庞大、本地和远程多台服务器、多段网络、多容灾任务的情况.     

利用DRBD和Pacemaker技术构建高可用数据容灾备份系统

为充分保证数据信息安全,提高数据中心容灾备份能力,以DRBD和Pacemaker技术为基础构建具有高可用性的数据容灾备份系统,实现生产数据在本地、异地之间三台服务器的镜像复制,并且实现应用和数据两个级别的高可用(HA),解决目前主流SAN存储环境下共享磁盘阵列的单点故障威胁,有效满足不断提升的数据恢复RTO和RPO的要求.本论述为数据中心业务系统高可用和数据异地备份提出了低成本的技术方案.     

宜兴市社保信息系统应用级容灾的设计与实施

宜兴市社保应用级客灾系统由市人社局信息中心机房和市政府容灾中心机房两部分组成,具有数据库多节点自动切换功能,实现了两中心同时实时运算,数据实时异地备份,对外应用服务灾难恢复.     

一种多点网络异地数据备份恢复方法

为了解决容灾系统中单个备份服务器带来的性能瓶颈,本文提出了一种多点网络异地数据备份恢复方法MRDBR.该方法实时监控逻辑卷的数据变化,将监控到的数据变化记录通过海量缓存发送至多个备份服务器进行写重放,完成对本地数据的多点备份.在灾难发生后,根据备份服务器的负载情况,从各备份服务器对任务的差异数据进行并发恢复,并动态调整各备份源的恢复任务,最后在本地进行数据拼合,完成快速恢复.实验证明,该方法具有多点备份、性能稳定、恢复速度快等优点.     

小灵通短信系统的灾难恢复方案

现代企业的运作日益依赖于信息技术,信息数据的丢失和损坏将对企业造成难以估量的损失,如何抵御大规模的灾难事件受到人们越来越多的关注,研制安全、高效、价廉的容灾系统势在必行.本文为某市网通公司的小灵通短信平台设计开发了一套容灾系统,容灾系统的灾难检测及恢复模块利用改进的心跳检测方法,时时监控本地各节点的主/热备机的工作状态和节点间的网络连接状态.方案建立了本地数据备份中心,与应用系统的数据库保持时时同步,建立远离本地的远程数据备份中心,通过Internet定时将本地应用系统数据库生成的数据库备份文件的备份拷贝到远程数据备份中心.整个容灾系统具有价廉、安全和高效的特点,并且稳定运行了一年.     

市级异地电子政务容灾备份系统建设

随着电子政务应用的不断加强,电子政务应用系统中的各类数据越来越重要地成为各级党政机关的战略资源,但是各种意外事件如：电力中断、硬件故障、软件Bug、恶性病毒的破坏、人为错误等造成的关键数据丢失或不可用,如不能及时得到恢复,将严重影响各级党政机关工作的正常开展。因此,容灾备份系统逐渐受到各级党政机关信息主管部门的关注,本文以容灾备份技术相关情况进行阐述,并以绍兴市异地电子政务容灾备份系统建设实践为例,来探讨地市级政府异地电子政务容灾备份系统的建设。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with