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关键词： 计算机档案管理   安全保护措施   数据库应用系统   数据库系统   内部计算机   机密数据   网络黑客   数据存储  

摘要： 现代企业计算机档案管理信息系统是以数据存储和查询为特征的数据库应用系统,保护数据库系统的安全与完整,保持系统正常运行以及防止机密数据泄露是计算机档案安全保护的内容。笔者从企业计算机档案管理载体与应用系统角度入手,针对计算机档案管理工作提出切实可行的安全保护措施。

关键词： 包头医学院   中国学术期刊(光盘版)   中文生物医学期刊数据库   中国生物医学光盘数据库   学报   数据库系统   中国期刊网   稿约  

摘要： 《包头医学院学报》是医学综合性学术期刊（双月刊），经国家科委和新闻出版总署批准，国内外公开发行。设有基础医学、预防医学、临床医学、祖国医学、技术方法、病例报道、综述、教学与管理等栏目。本刊被评为“北方优秀期刊”、“内蒙古优秀科技期刊”，被《中国核心期刊（遴选）数据库》、《中国期刊网》、《中国学术期刊（光盘版）》、《万方数据库系统（ChinaInfo）》全文收录，为《中国学术期刊综合评价数据库》统计源期刊，被《美国化学文摘（CA）》、《中文生物医学期刊数据库（CMCC）》、《中国生物医学光盘数据库（CBMDisc）》等数据库收录。

关键词： data-intensive workflow   parallel database system   user-defined executable   collective query  

摘要： To better support data-intensive workflows which are typically built out of various independently developed executables, this paper proposes extensions to parallel database systems called User-Defined eXecutables (UDX) and collective queries. UDX facilitates the description of workflows by enabling seamless integrations of external executables into SQL statements without any efforts to write programs confirming to strict specifications of databases. A collective query is an SQL query whose results are distributed to multiple clients and then processed by them in parallel, using arbitrary UDX. It provides efficient parallelization of executables through the data transfer optimization algorithms that distribute query results to multiple clients, taking both communication cost and computational loads into account. We implement this concept in a system called Para Lite, a parallel database system based on a popular lightweight database SQLite. Our experiments show that Para Lite has several times higher performance over Hive for typical SQL tasks and has 10x speedup compared to a commercial DBMS for executables. In addition, this paper studies a real-world text processing workflow and builds it on top of Para Lite, Hadoop, Hive and general files. Our experiences indicate that Para Lite outperforms other systems in both productivity and performance for the workflow.

关键词： monovalent rotavirus vaccine   pentavalent rotavirus vaccine   network meta-analysis   comparative effectiveness research   Cochrane Database Systematic Review  

摘要： To assess the comparative effectiveness of a monovalent and a pentavalent rotavirus vaccine (RV1 and RV5), a Bayesian network meta-analysis was conducted. Data of randomized trials from the Cochrane Review in 2012 were extracted and synthesized. For the prevention of severe rotavirus disease up to 2 years, no statistical difference was found in the effectiveness between the 2 types of vaccine (odds ratio: 2.23, 95% credible interval: 0.71-5.20). Similarly, the comparative effectiveness of RV1 and RV5 appeared equivalent for other rotavirus-associated outcome measures, such as prevention of severe disease up to 1 year and all severity of rotavirus infections for up to both 1- and 2-year follow-ups. These results indicates that, overall, RV1 and RV5 offer similar benefits to prevent rotavirus diseases;nonetheless, credible intervals are generally wide, highlighting the necessity of further meta-analyses including updated information or, ideally, controlled trials comparing both vaccines directly.

关键词： Algorithms   Design   Performance   Reliability   Determinism   distributed database systems   replication   transaction processing  

摘要： As more data management software is designed for deployment in public and private clouds, or on a cluster of commodity servers, new distributed storage systems increasingly achieve high data access throughput via partitioning and replication. In order to achieve high scalability, however, today's systems generally reduce transactional support, disallowing single transactions from spanning multiple partitions. This article describes Calvin, a practical transaction scheduling and data replication layer that uses a deterministic ordering guarantee to significantly reduce the normally prohibitive contention costs associated with distributed transactions. This allows near-linear scalability on a cluster of commodity machines, without eliminating traditional transactional guarantees, introducing a single point of failure, or requiring application developers to reason about data partitioning. By replicating transaction inputs instead of transactional actions, Calvin is able to support multiple consistency levels-including Paxos-based strong consistency across geographically distant replicas-at no cost to transactional throughput. Furthermore, Calvin introduces a set of tools that will allow application developers to gain the full performance benefit of Calvin's server-side transaction scheduling mechanisms without introducing the additional code complexity and inconvenience normally associated with using DBMS stored procedures in place of ad hoc client-side transactions.

关键词： SQLite数据库   MFC   嵌入式开发   监控日志管理  

摘要： 为解决传统监控日志录入不规范及数据管理差的弊端，提出了一种基于mfc定制前端，和嵌入式数据库SQLite作为后台调度的解决方案，并且已在天津网络广播电视台运维部的工作中得到了有效的应用。介绍了此系统的开发设想、开发技术、功能应用等。实践表明，该系统的引入对运维部门信息管理、数据分析能充分发挥其高效、精确的优势。

关键词： 天梭   K1   数字化城市   业务主机   数据库系统   平台迁移   城市发展   城市管理   数据迁移   数字城市  

摘要： 浪潮工程师对廊坊工信局现有的5大数据库系统进行了完整的梳理和应用分析,对从X86服务器平台迁移到天梭K1关键业务主机进行了评估,并制定了相应的解决方案。目前,浪潮天梭K1承载的数字化城市管理系统运行稳定,完全满足廊坊未来五年城市发展的业务需求。

关键词： oursera   数据库系统设计  

摘要： 利用数据库应用系统Access设计并研究开发完成了Coursera医学课程数据库系统,从而便于用户通过简单的操作了解自己感兴趣的课程。

关键词： 数据库   客户机   服务器模式   浏览器   服务器模式  

摘要： 针对客户机/服务器(C/S)模式数据库系统开放性有限、维护成本高,而浏览器/服务器(B/S)模式响应速度受网络传输容量影响较大、系统安全性相对较低的问题,提出了混合模式的数据库系统结构。该结构由C/S与B/S两种模式混合而成,对不同的应用有针对性地采用不同的实现模式,最终通过系统间功能的整合实现整个结构模式的统一。应用实例表明,该数据库系统结构能有效兼顾系统开放性和安全性、有效降低系统维护成本。

关键词： 农业大学学报   自然科学   科学技术   数据库   数据库系统   云南