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PC Cluster环境下基于多维数组的Data Cube算法 被引量:1
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作者 李盛恩 李翠平 +1 位作者 王珊 杜小勇 《微电子学与计算机》 CSCD 北大核心 2003年第8期1-5,30,共6页
因为需要存取大量的数据,计算datacube要花费大量的时间和存储空间。本文研究了使用便宜的PC机群计算datacube的方法。我们使用多维数组作为存储结构,并将数组划分成若干个分片,对每个分片进行压缩以节约存储空间、减少存取时间和增量... 因为需要存取大量的数据,计算datacube要花费大量的时间和存储空间。本文研究了使用便宜的PC机群计算datacube的方法。我们使用多维数组作为存储结构,并将数组划分成若干个分片,对每个分片进行压缩以节约存储空间、减少存取时间和增量维护时间,分片被分布到不同的处理机。我们提出了一个新的流水线组织方法以及对分片建立索引的思想,大大减少了外排序的代价和存取磁盘的次数。实验结果表明我们的算法具有一定的伸缩性。 展开更多
关键词 数据仓库 多维数组 datacube算法 联机分析 PC机
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An Application of a Multi-Tier Data Warehouse in Oil and Gas Drilling Information Management 被引量:2
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作者 张宁生 王志伟 《Petroleum Science》 SCIE CAS CSCD 2004年第4期1-5,共5页
Expenditure on wells constitute a significant part of the operational costs for a petroleum enterprise, where most of the cost results from drilling. This has prompted drilling departments to continuously look for wa... Expenditure on wells constitute a significant part of the operational costs for a petroleum enterprise, where most of the cost results from drilling. This has prompted drilling departments to continuously look for ways to reduce their drilling costs and be as efficient as possible. A system called the Drilling Comprehensive Information Management and Application System (DCIMAS) is developed and presented here, with an aim at collecting, storing and making full use of the valuable well data and information relating to all drilling activities and operations. The DCIMAS comprises three main parts, including a data collection and transmission system, a data warehouse (DW) management system, and an integrated platform of core applications. With the support of the application platform, the DW management system is introduced, whereby the operation data are captured at well sites and transmitted electronically to a data warehouse via transmission equipment and ETL (extract, transformation and load) tools. With the high quality of the data guaranteed, our central task is to make the best use of the operation data and information for drilling analysis and to provide further information to guide later production stages. Applications have been developed and integrated on a uniform platform to interface directly with different layers of the multi-tier DW. Now, engineers in every department spend less time on data handling and more time on applying technology in their real work with the system. 展开更多
关键词 drilling information management multi-tier data warehouse information processing application system
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XML Based Data Cube and X-OLAP
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作者 王晓玲 董逸生 《Journal of Southeast University(English Edition)》 EI CAS 2001年第2期5-9,共5页
Data warehouse provides storage and management for mass data, but data schema evolves with time on. When data schema is changed, added or deleted, the data in data warehouse must comply with the changed data schema, ... Data warehouse provides storage and management for mass data, but data schema evolves with time on. When data schema is changed, added or deleted, the data in data warehouse must comply with the changed data schema, so data warehouse must be re organized or re constructed, but this process is exhausting and wasteful. In order to cope with these problems, this paper develops an approach to model data cube with XML, which emerges as a universal format for data exchange on the Web and which can make data warehouse flexible and scalable. This paper also extends OLAP algebra for XML based data cube, which is called X OLAP. 展开更多
关键词 data warehouse data cube XML X OLAP semi structured data
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基于时态层次链的Data Cube多版本维护方案 被引量:1
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作者 肖磊 胡众义 《计算机系统应用》 2010年第1期161-164,共4页
针对Data Cube的模式变动造成的多版本问题,对时态聚集关系与时态层次链进行了形式化描述,并基于这些关系实现了多个版本的Data Cube的统一生成算法,不仅可以高效地进行Data Cube多个版本的维护,而且在OLAP查询也可以基于时态层次链来执... 针对Data Cube的模式变动造成的多版本问题,对时态聚集关系与时态层次链进行了形式化描述,并基于这些关系实现了多个版本的Data Cube的统一生成算法,不仅可以高效地进行Data Cube多个版本的维护,而且在OLAP查询也可以基于时态层次链来执行,从而提高系统的整体效率。 展开更多
关键词 时态层次链 多维数据集 多版本维护
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Uniform Representation Model for Metadata of Data Warehouse
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作者 王建芬 曹元大 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期85-88,共4页
A uniform metadata representation is introduced for heterogeneous databases, multi media information and other information sources. Some features about metadata are analyzed. The limitation of existing metadata model... A uniform metadata representation is introduced for heterogeneous databases, multi media information and other information sources. Some features about metadata are analyzed. The limitation of existing metadata model is compared with the new one. The metadata model is described in XML which is fit for metadata denotation and exchange. The well structured data, semi structured data and those exterior file data without structure are described in the metadata model. The model provides feasibility and extensibility for constructing uniform metadata model of data warehouse. 展开更多
关键词 data warehouse METAdata data model XML
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基于语义的Data Cube数字水印技术
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作者 杨科华 杨宇华 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2010年第2期70-73,共4页
数字水印技术可以有效地保护版权,数据仓库中用于OLAP(OnLine Analyti-cal Processing,联机分析处理)的Data Cube(数据立方体,亦称多维数据集)不仅包含有价值的数据,而且其设计模式与分析模式也体现了Data Cube拥有者的知识产权.将数字... 数字水印技术可以有效地保护版权,数据仓库中用于OLAP(OnLine Analyti-cal Processing,联机分析处理)的Data Cube(数据立方体,亦称多维数据集)不仅包含有价值的数据,而且其设计模式与分析模式也体现了Data Cube拥有者的知识产权.将数字水印技术引入Data Cube中,并充分利用Data Cube的语义信息,从而提供一个通用、实用的Da-ta Cube数字水印技术解决方案. 展开更多
关键词 数字水印 语义 数据立方体 版权
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一种基于多层次链的Data Cube维层次编码
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作者 杨科华 张伟 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2007年第9期74-77,共4页
研究了Data Cube的索引技术,提出一种能够处理复杂维层次结构情况的维层次编码.维层次编码充分利用了Data Cube中维的层次性及其语义特性,结合二进制编码与维层次结构编码对维成员值进行编码,通过二进制操作,可以快速检索出与查询关键... 研究了Data Cube的索引技术,提出一种能够处理复杂维层次结构情况的维层次编码.维层次编码充分利用了Data Cube中维的层次性及其语义特性,结合二进制编码与维层次结构编码对维成员值进行编码,通过二进制操作,可以快速检索出与查询关键字相匹配的维层次编码.同时,基于维层次编码定义的层次链掩码,层次掩码及检索函数能够充分利用多维数据中的语义信息,实现基于语义的检索,减少了I/O开销,提高了OLAP查询效率. 展开更多
关键词 索引 数据立方体 联机分析处理 维层次编码
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基于Data Warehouse技术的数据可视化的应用 被引量:2
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作者 赵欣 赵海 徐凌宇 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2000年第4期365-367,共3页
给出了一个基于DataWarehouse技术的市民投诉系统的设计与实现·系统由管理子系统、语音信箱、分析决策子系统 3部分组成 ,其中分析决策子系统是实现的关键·采用DataWarehouse技术 ,以ROLAP为主要方法 ,将数据可视化技术应用于... 给出了一个基于DataWarehouse技术的市民投诉系统的设计与实现·系统由管理子系统、语音信箱、分析决策子系统 3部分组成 ,其中分析决策子系统是实现的关键·采用DataWarehouse技术 ,以ROLAP为主要方法 ,将数据可视化技术应用于DataWarehouse,实现了多维数据的可视化处理·系统已在多个城市的投诉中心投入运行 ,取得了良好的社会效益· 展开更多
关键词 datawarehouse DSS系统 数据可视化 数据仓库
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基于data cube的成绩分析系统的设计 被引量:1
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作者 朱江 周斌 《长江大学学报(自然科学版)》 CAS 2011年第5期97-99,共3页
现有成绩分析系统只是将成绩作为一个数据利用查询语句加以简单统计和表示,并没有真正的实现分析功能,针对这一状况设计了一种基于数据立方体(data cube)的成绩分析系统。该系统能实现多维、多层次地分析,为教学效果的评估提供定量的数... 现有成绩分析系统只是将成绩作为一个数据利用查询语句加以简单统计和表示,并没有真正的实现分析功能,针对这一状况设计了一种基于数据立方体(data cube)的成绩分析系统。该系统能实现多维、多层次地分析,为教学效果的评估提供定量的数据支持,有助于提高评估体系的客观性和公正性,并为教育教学改革提供可行的策略和方法。 展开更多
关键词 成绩分析系统 数据立方体(data cube) 评估体系
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Development of Geological Data Warehouse 被引量:2
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作者 LiZhenhua HuGuangdao ZhangZhenfei 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期261-264,共4页
Data warehouse (DW), a new technology invented in 1990s, is more useful for integrating and analyzing massive data than traditional database. Its application in geology field can be divided into 3 phrases: 1992-1996,... Data warehouse (DW), a new technology invented in 1990s, is more useful for integrating and analyzing massive data than traditional database. Its application in geology field can be divided into 3 phrases: 1992-1996, commercial data warehouse (CDW) appeared; 1996-1999, geological data warehouse (GDW) appeared and the geologists or geographers realized the importance of DW and began the studies on it, but the practical DW still followed the framework of DB; 2000 to present, geological data warehouse grows, and the theory of geo-spatial data warehouse (GSDW) has been developed but the research in geological area is still deficient except that in geography. Although some developments of GDW have been made, its core still follows the CDW-organizing data by time and brings about 3 problems: difficult to integrate the geological data, for the data feature more space than time; hard to store the massive data in different levels due to the same reason; hardly support the spatial analysis if the data are organized by time as CDW does. So the GDW should be redesigned by organizing data by scale in order to store mass data in different levels and synthesize the data in different granularities, and choosing space control points to replace the former time control points so as to integrate different types of data by the method of storing one type data as one layer and then to superpose the layers. In addition, data cube, a wide used technology in CDW, will be no use in GDW, for the causality among the geological data is not so obvious as commercial data, as the data are the mixed result of many complex rules, and their analysis always needs the special geological methods and software; on the other hand, data cube for mass and complex geo-data will devour too much store space to be practical. On this point, the main purpose of GDW may be fit for data integration unlike CDW for data analysis. 展开更多
关键词 data warehouse (DW) geological data warehouse (GDW) space control points data cube
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基于改进Marching Cubes算法的雷达气象数据三维重建
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作者 魏敏 李足镇 李旭 《软件导刊》 2024年第9期181-186,共6页
在气象领域中,多普勒天气雷达探测到的气象数据采用以雷达站点为原点的三维极坐标系进行存储,具有形状不规则、数据量大等特征。Marching Cubes(MC)算法是三维重建中的经典算法,但应用于气象领域时存在重建效率低下和不能直接处理气象... 在气象领域中,多普勒天气雷达探测到的气象数据采用以雷达站点为原点的三维极坐标系进行存储,具有形状不规则、数据量大等特征。Marching Cubes(MC)算法是三维重建中的经典算法,但应用于气象领域时存在重建效率低下和不能直接处理气象数据的缺点。为了实现气象数据的三维重建,基于MC算法提出雷达数据归一化处理与状态标记判别算法NBV-MC。该算法根据雷达基数据文件的特点对其进行归一化预处理,使用雷达基数据构建拟梯形六面体体素,对每一个六面体体素进行状态标记,在遍历六面体体素时动态判别其是否需要处理。实验结果表明,NBV-MC算法不仅解决了由于气象数据具有不规则性而不能直接用于MC算法的问题,而且可以在保证数据真实性和重建效果的情况下有效减少绘制等值面所需要的三角面片数量,提高重建速度。与MC算法相比,NBV-MC算法的重建效率提升了77.70%以上,有利于实时场景交互,便于气象研究人员直接分析雷达数据。 展开更多
关键词 多普勒天气雷达数据 三维重建 Marchingcubes算法
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Fast Computation of Sparse Data Cubes with Constraints 被引量:2
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作者 FengYu-cai ChenChang-qing FengJian-lin XiangLong-gang 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第2期167-172,共6页
For a data cube there are always constraints between dimensions or among attributes in a dimension, such as functional dependencies. We introduce the problem that when there are functional dependencies, how to use the... For a data cube there are always constraints between dimensions or among attributes in a dimension, such as functional dependencies. We introduce the problem that when there are functional dependencies, how to use them to speed up the computation of sparse data cubes. A new algorithm CFD (Computation by Functional Dependencies) is presented to satisfy this demand. CFD determines the order of dimensions by considering cardinalities of dimensions and functional dependencies between dimensions together, thus reduce the number of partitions for such dimensions. CFD also combines partitioning from bottom to up and aggregate computation from top to bottom to speed up the computation further. CFD can efficiently compute a data cube with hierarchies in a dimension from the smallest granularity to the coarsest one. Key words sparse data cube - functional dependency - dimension - partition - CFD CLC number TP 311 Foundation item: Supported by the E-Government Project of the Ministry of Science and Technology of China (2001BA110B01)Biography: Feng Yu-cai (1945-), male, Professor, research direction: database system. 展开更多
关键词 sparse data cube functional dependency DIMENSION PARTITION CFD
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Data Warehouse Design for Big Data in Academia 被引量:2
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作者 Alex Rudniy 《Computers, Materials & Continua》 SCIE EI 2022年第4期979-992,共14页
This paper describes the process of design and construction of a data warehouse(“DW”)for an online learning platform using three prominent technologies,Microsoft SQL Server,MongoDB and Apache Hive.The three systems ... This paper describes the process of design and construction of a data warehouse(“DW”)for an online learning platform using three prominent technologies,Microsoft SQL Server,MongoDB and Apache Hive.The three systems are evaluated for corpus construction and descriptive analytics.The case also demonstrates the value of evidence-centered design principles for data warehouse design that is sustainable enough to adapt to the demands of handling big data in a variety of contexts.Additionally,the paper addresses maintainability-performance tradeoff,storage considerations and accessibility of big data corpora.In this NSF-sponsored work,the data were processed,transformed,and stored in the three versions of a data warehouse in search for a better performing and more suitable platform.The data warehouse engines-a relational database,a No-SQL database,and a big data technology for parallel computations-were subjected to principled analysis.Design,construction and evaluation of a data warehouse were scrutinized to find improved ways of storing,organizing and extracting information.The work also examines building corpora,performing ad-hoc extractions,and ensuring confidentiality.It was found that Apache Hive demonstrated the best processing time followed by SQL Server and MongoDB.In the aspect of analytical queries,the SQL Server was a top performer followed by MongoDB and Hive.This paper also discusses a novel process for render students anonymity complying with Family Educational Rights and Privacy Act regulations.Five phases for DW design are recommended:1)Establishing goals at the outset based on Evidence-Centered Design principles;2)Recognizing the unique demands of student data and use;3)Adopting a model that integrates cost with technical considerations;4)Designing a comparative database and 5)Planning for a DW design that is sustainable.Recommendations for future research include attempting DW design in contexts involving larger data sets,more refined operations,and ensuring attention is paid to sustainability of operations. 展开更多
关键词 Big data data warehouse MONGODB Apache hive SQL server
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Preliminary Study in Spatial Data Warehouse of Flood Control and Disaster Mitigation in Yangtze River Basin
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作者 ZHAN Xiao guoSenior engineer, Yangtze River Scientific Research Institute, Changjiang Water Resources Commission, Wuhan 430010, China 《人民长江》 北大核心 2002年第S1期90-92,共3页
Since 1990s,the spatial data warehouse technology has rapidly been developing, but due to the complexity of multi-dimensional analysis, extensive application of the spatial data warehouse technology is affected. In th... Since 1990s,the spatial data warehouse technology has rapidly been developing, but due to the complexity of multi-dimensional analysis, extensive application of the spatial data warehouse technology is affected. In the light of the characteristics of the flood control and disaster mitigation in the Yangtze river basin, it is proposed to design a scheme about the subjects and data distribution of the spatial data warehouse of the flood control and disaster mitigation in Yangtze river basin, i.e., to adopt a distributed scheme. The creation and development of the spatial data warehouse of the flood control and disaster mitigation in Yangtze river basin is presented .The necessity and urgency of establishing the spatial data warehouse is expounded from the viewpoint of the present situation being short of available information for the flood control and disaster mitigation in Yangtze river basin. 展开更多
关键词 spatial data warehouse distributional scheme FLOOD control and DISASTER MITIGATION YANGTZE RIVER
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一种特殊DATA CUBE的技术研究
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作者 叶茂枝 《乐山师范学院学报》 2013年第5期49-51,共3页
封闭数据立方体利用元组间的关联,除去冗余信息,在减小数据立方体体积的同时,避免了查询时的解压缩。从源数据的分组角度对封闭数据立方体概念进行了解释,并在此基础上详细分析了由于源数据的更新而导致的对应封闭数据立方体的更新过程... 封闭数据立方体利用元组间的关联,除去冗余信息,在减小数据立方体体积的同时,避免了查询时的解压缩。从源数据的分组角度对封闭数据立方体概念进行了解释,并在此基础上详细分析了由于源数据的更新而导致的对应封闭数据立方体的更新过程,给出了更新算法的框架。 展开更多
关键词 datacube 分组 更新 算法框架
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ROLE OF META-MODEL IN ENGINEERING DATA WAREHOUSE
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作者 SHENGuo-hua HUANGZhi-qiu WANGChuan-dong 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第4期317-321,共5页
Engineering data are separately organized and their schemas are increasingly complex and variable. Engineering data management systems are needed to be able to manage the unified data and to be both customizable and e... Engineering data are separately organized and their schemas are increasingly complex and variable. Engineering data management systems are needed to be able to manage the unified data and to be both customizable and extensible. The design of the systems is heavily dependent on the flexibility and self-description of the data model. The characteristics of engineering data and their management facts are analyzed. Then engineering data warehouse (EDW) architecture and multi-layer metamodels are presented. Also an approach to manage anduse engineering data by a meta object is proposed. Finally, an application flight test EDW system (FTEDWS) is described and meta-objects to manage engineering data in the data warehouse are used. It shows that adopting a meta-modeling approach provides a support for interchangeability and a sufficiently flexible environment in which the system evolution and the reusability can be handled. 展开更多
关键词 data warehouse meta model engineering data management SELF-DESCRIPTION
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Study on Material ManagementSystem of Coal Enterprise Basedon Data Warehouse
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作者 庄玉良 《Journal of China University of Mining and Technology》 2004年第2期127-132,共6页
On the bas is of the reality of material supply management of the coal enterprise, this paper expounds plans of material management systems based on specific IT, and indicates the deficiencies, the problems of them an... On the bas is of the reality of material supply management of the coal enterprise, this paper expounds plans of material management systems based on specific IT, and indicates the deficiencies, the problems of them and the necessity of improving them. The structure, models and data organizing schema of the material management decision support system are investigated based on a new data management technology (data warehousing technology). 展开更多
关键词 coal ENTERPRISE data warehouse DECISION support SYSTEM MANAGEMENT information SYSTEM material MANAGEMENT
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Optimal Genetic View Selection Algorithm for Data Warehouse
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作者 王自强 冯博琴 《Journal of Southwest Jiaotong University(English Edition)》 2005年第1期5-10,共6页
To efficiently solve the materialized view selection problem, an optimal genetic algorithm of how to select a set of views to be materialized is proposed so as to achieve both good query performance and low view maint... To efficiently solve the materialized view selection problem, an optimal genetic algorithm of how to select a set of views to be materialized is proposed so as to achieve both good query performance and low view maintenance cost under a storage space constraint. First, a pre-processing algorithm based on the maximum benefit per unit space is used to generate initial solutions. Then, the initial solutions are improved by the genetic algorithm having the mixture of optimal strategies. Furthermore, the generated infeasible solutions during the evolution process are repaired by loss function. The experimental results show that the proposed algorithm outperforms the heuristic algorithm and canonical genetic algorithm in finding optimal solutions. 展开更多
关键词 data warehouse Genetic algorithm View selection AND-OR graph
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Web-based: A data warehouse on osteoporosis data warehouse in the osteoporosis community health information management system
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作者 Qiang Wang Yingchao Shen 《Journal of Biomedical Science and Engineering》 2013年第11期1072-1076,共5页
Objective: To establish an interactive management model for community-oriented high-risk osteoporosis in conjunction with a rural community health service center. Materials and Methods: Toward multidimensional analysi... Objective: To establish an interactive management model for community-oriented high-risk osteoporosis in conjunction with a rural community health service center. Materials and Methods: Toward multidimensional analysis of data, the system we developed combines basic principles of data warehouse technology oriented to the needs of community health services. This paper introduces the steps we took in constructing the data warehouse;the case presented here is that of a district community health management information system in Changshu, Jiangsu Province, China. For our data warehouse, we chose the MySQL 4.5 relational database, the Browser/Server, (B/S) model, and hypertext preprocessor as the development tools. Results: The system allowed online analysis processing and next-stage work preparation, and provided a platform for data management, data query, online analysis, etc., in community health service center, specialist outpatient for osteoporosis, and health administration sectors. Conclusion: The users of remote management system and data warehouse can include community health service centers, osteoporosis departments of hospitals, and health administration departments;provide reference for policymaking of health administrators, residents’ health information, and intervention suggestions for general practitioners in community health service centers, patients’ follow-up information for osteoporosis specialists in general hospitals. 展开更多
关键词 COMMUNITY MANAGEMENT data warehouse Information MANAGEMENT System OSTEOPOROSIS Remote MANAGEMENT of OSTEOPOROSIS
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Web Data Cube Construction in Multidimensional On-line Analytical Processing Environment
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作者 朱焱 《Journal of Southwest Jiaotong University(English Edition)》 2007年第1期1-7,共7页
This paper investigates how to integrate Web data into a multidimensional data warehouse (cube) for comprehensive on-line analytical processing (OLAP) and decision making. An approach for Web data-based cube const... This paper investigates how to integrate Web data into a multidimensional data warehouse (cube) for comprehensive on-line analytical processing (OLAP) and decision making. An approach for Web data-based cube construction is proposed, which includes Web data modeling based on MIX ( Metadam based Integration model for data X-change ), generic and specific mapping rules design, and a transformation algorithm for mapping Web data to a multidimensional array. Besides, the structure and implementation of the prototype of a Web data base cube are discussed. 展开更多
关键词 Web data warehousing Web data-based cube MOLAP
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