共查询到20条相似文献，搜索用时 31 毫秒
1.
The University of Florida GeoPlan Center has been organizing, standardizing, and distributing geospatial data since 1998 through the Florida Geographic Data Library (FGDL), a collection of Florida geospatial data from various agencies, as well as data developed in-house. With funding from the Florida Department of Transportation (FDOT), FGDL serves as a public distribution mechanism for hundreds of Florida geospatial data layers. Since 2004, FGDL layers have formed the data foundation for FDOT's interagency application known as efficient transportation decision making (ETDM), which facilitates the review and permitting process for proposed transportation projects. Data layers are standardized and inspected to ensure that the data are adequate for use in analysis and decision making. To efficiently manage the geospatial data and workflows, a quality assurance/quality control (QAQC) process and relational database schema was developed to track the standardization procedures, lineage, versioning, and archiving of the data layers. This article details the history of the Florida Geographic Data Library, challenges of managing a large geospatial data repository, development of a QAQC process and database schema, and lessons learned. 相似文献
2.
Esperanza Marcos Belén Vela JoséMaría Cavero 《Informatik - Forschung und Entwicklung》2004,2(1):152-164
The most common way of designing databases is by means of a conceptual model, such as E/R, without taking into account other views of the system. New object-oriented design languages, such as UML (Unified Modelling Language), allow the whole system, including the database schema, to be modelled in a uniform way. Moreover, as UML is an extendable language, it allows for any necessary introduction of new stereotypes for specific applications. Proposals exist to extend UML with stereotypes for database design but, unfortunately, they are focused on relational databases. However, new applications require complex objects to be represented in complex relationships, object-relational databases being more appropriate for these requirements. The framework of this paper is an Object-Relational Database Design Methodology, which defines new UML stereotypes for Object-Relational Database Design and proposes some guidelines to translate a UML conceptual schema into an object-relational schema. The guidelines are based on the SQL: 1999 object-relational model and on Oracle8i as a product example. 相似文献
3.
本文采用ＢＯＲＬＡＮＤＩＤＡＰＩ关系数据库集成技术，集成多种关系数据库系统，并用信息存储与检索软件ＱＵＩＣＫＩＭＳ进行管理，实现对关系数据库的全文检索。对基于ＰＣ和基于ＳＱＬ的关系数据库数据结构、数据访问方式、数据类型进行集成；对基本表和单库或多库查询的结果进行转移，生成ＱＵＩＣＫＩＭＳ的必要文件和索引；对关系数据库提供布尔检索、前方一致检索、字段限定检索、相邻检索和位置检索等检索方式。采用动态转换关系数据库数据，减少了空间的浪费 相似文献
4.
Esperanza Marcos Belén Vela und José María Cavero 《Informatik - Forschung und Entwicklung》2004,18(3-4):152-164
The most common way of designing databases is by means of a conceptual model, such as E/R, without taking into account other views of the system. New object-oriented design languages, such as UML (Unified Modelling Language), allow the whole system, including the database schema, to be modelled in a uniform way. Moreover, as UML is an extendable language, it allows for any necessary introduction of new stereotypes for specific applications. Proposals exist to extend UML with stereotypes for database design but, unfortunately, they are focused on relational databases. However, new applications require complex objects to be represented in complex relationships, object-relational databases being more appropriate for these requirements. The framework of this paper is an Object-Relational Database Design Methodology, which defines new UML stereotypes for Object-Relational Database Design and proposes some guidelines to translate a UML conceptual schema into an object-relational schema. The guidelines are based on the SQL: 1999 object-relational model and on Oracle8i as a product example.Received: 22 January 2002, Revised: 10 June 2002, This paper is a revised and extended version of Extending UML for Object-Relational Database Design, presented in the UML2001 conference [17]. 相似文献
5.
《Microprocessing and Microprogramming》1994,40(10-12):737-741
This paper presents the potential for case-based reasoning in design problems, specifically as applied to relational database schema design. The proposed system relies on two case-bases that consist of a Domain Dependent Case-Base (DDCB) and a Domain Independent Case-Base (DICB). We focus on the DDCB in this paper. The organization of domain dependent cases and their features for design are identified. The strategies for retrieving the relevant cases, for building a rough solution, for repairing the rough solution, and for learning cases, currently under development, are also described. 相似文献
6.
全面介绍了解放军医学图书馆最新研发的《中国生物医学期刊引文数据库》机构知识版的新功能。《中国生物医学期刊引文数据库》机构知识版以 RDF 语义对机构、作者、基金、期刊和文献进行了统一描述,以机构库、作者库、基金库、期刊库和文献库为核心,基于文献标注信息对文献内容进行深入挖掘与分析,实现了对生物医学领域的信息资源关联;具备发表文献查询、引文查询、快速出具引证报告等功能,强化了文献计量可视化分析功能,发布各类 TOP 排行统计,推送关联信息,还增加了机构文献管理模块,可为各个机构提供个性化的文献管理和评价服务。 相似文献
7.
8.
深入研究一系列保持完整性约束的关系模式到XML Schema的转换规则和算法,对转换规则和算法中的不足进行补充完善。针对转换后XML Schema中存在基于XPath相对路径无效查询问题,提出在模式转换过程中建立相应索引文件的方法。文中给出了应用实例,说明对XML Schema查询时可以获取关系结构信息,提高查询效率。 相似文献
9.
文献计量分析中的数据准备工作研究 总被引：1，自引：0，他引：1
数据准备工作是文献计量分析的基础,它主要包括数据采集和数据清洗两个方面。数据的准确性直接影响文献计量分析结果的客观性。通过几个检索案例对比分析发现,数据准备工作在文献计量分析研究中十分重要。研究者可从以下4个方面改进数据准备工作:分析信息需求,选用合适的检索方法;掌握数据库的使用方法;尽量提高查全率,及时补充遗漏数据;删除误检数据。 相似文献
10.
本文构建了数字档案馆研究主题分类表,包括13个一级主题类目和相应的二级主题类目。并以此为基础,选择了自“数字档案馆”概念出现以来15年间（1998～2013年）WOS和CNKI收录的数字档案馆研究论文,主要从研究主题方面对文献进行计量分析与比较,讨论了国内外数字档案馆研究的相似与不同之处。 相似文献
11.
This study provides further validation of the relational message scales (Burgoon & Hale, 1987). The “preferred” relational message schema presented by Burgoon and Hale is shown to be internally consistent, reliable, and to reflect changes in communication as relationships increase in intimacy. 相似文献
12.
This paper presents the results of a bibliometric study of the scientific publications that are affiliated with Russia and
included in multidisciplinary databases, such as Science Citation Index and Scopus, as well as in the specialized Chemical
Abstracts database, in the period from 2005 to 2009. Major bibliometric indicators, including citation indexes, are explored.
It is shown that the Scopus database contains most of the Russian publications in the period from 2005 to 2009. While a gradual
decrease in the number of peer-reviewed Russian-language journals constitutes a general trend for all three databases, the
Chemical Abstracts database leads in terms of the coverage of these journals. It is found that despite the large number of
translated versions of journals, Russian publications are still significantly late in their coverage by foreign databases,
which has a significant impact on their citation levels. 相似文献
13.
14.
选择CNKI数据库,运用文献计量分析方法、计算机统计分析技术、词频分析方法、共词分析方法、社会网络分析软件等对文献编目领域的历史文献进行计量分析,通过绘制文献数量分布图、文献期刊分布图、作者合著网络,挖掘当前文献编目领域的发展趋势、研究水平、高影响力作者及合作情况、研究概况等信息,以期让读者对国内文献编目领域的研究趋势、研究力量的分布、领域合作情况、研究概况有一个直观、清晰的认识,为以后的研究工作提供一个指引。 相似文献
15.
Librarians have used bibliometrics for many years to assess collections and to provide data for making selection and deselection decisions. With the advent of new technology--specifically, CD-ROM databases and reprint file database management programs--new cost-effective procedures can be developed. This paper describes a recent multidisciplinary study conducted by two library faculty members and one allied health faculty member to test a bibliometric method that used the MEDLINE and CINAHL databases on CD-ROM and the Papyrus database management program to produce a new collection development methodology. 相似文献
16.
Gonçalo Paiva Dias 《Government Information Quarterly》2019,36(3):400-411
In this article it is presented a bibliometric analysis of e-government research in the Ibero-American (IA) Community. Data from the Scopus® database relating to 1129 research documents published between 2003 and 2017 was used. Presented analyzes include the most productive and impacting researchers, institutions and countries; determinants for country results; most relevant subject areas and specific research themes; and international cooperation patterns, namely within the IA Community. Contrary to what happens worldwide, e-government research production is still rising in IA. Besides the general heterogeneity, there are four relatively homogenous groups of countries to what concerns production and impact: leading, evolving, emerging, and expectant countries. IA has distinctive characteristics that make it interesting as an object of study and that constitute an opportunity for further development. Nevertheless, for results to continue to evolve, it is relevant that public policies related to e-government development and the promotion of research continue to be developed and that cooperation among IA researchers is properly promoted and supported. 相似文献
17.
任树怀 《现代图书情报技术》2004,20(7):41-44
Winisis是一个先进的信息存储与检索软件，由联合国教科文组织开发、维护和免费向世界各国推广，由于采用独特的数据库结构和倒排文档等关键技术，它在可变长记录处理和快速检索等方面具有很强的功能。本文对该软件的关键技术进行了深入研究和剖析。 相似文献
18.
面向网络信息资源聚合搜索的细粒度聚合单元元数据研究 总被引：1，自引：0，他引：1
由于相关信息片段分散分布在海量且复杂多样的网络信息资源中,用户往往需要花费大量时间浏览、查询和收集所需信息。面向聚合搜索的细粒度聚合单元元数据可以深入揭示信息特征及其关联关系,促进知识发现并提升知识服务效率。因此,有必要构建细粒度聚合单元的元数据描述框架。本文以图书情报领域开放获取期刊论文、在线百科、博客等网络信息资源为数据源,采用逻辑结构分析和形式结构分析方法建立聚合单元划分框架,包括篇章层级的标题、著者等外部特征,以及节段、句群、图表单元中的话语意图和语义功能等特征;通过分析聚合单元的属性特征及复用DC、LOM元数据元素,构建描述聚合单元访问信息、物理信息和语义信息的元数据框架;设计检索数据库并采用实验法对聚合单元元数据框架进行验证。实验表明,该元数据框架可支持多类型网络信息资源、各层级细粒度聚合单元的检索,可为细粒度信息聚合与搜索提供理论基础与实践指导。图7。表6。参考文献58。 相似文献
19.
E. A. Vasilenko V. I. Panfilov D. Yu. Zhukov D. V. Sivukha 《Scientific and Technical Information Processing》2013,40(4):240-244
The existing approaches to the definition of the scientific contributions made by researchers are analyzed. A bibliometric database is developed on the basis of the quantitative analysis of publication activities monitored by the most representative global citation systems, such as the Web of Science (Thomson Reuters, USA), Scopus (Elsevier, the Netherlands), and the Russian Science Citation Index (Scientific Electronic Library, the Russian Federation). The system allows teachers and researchers to consult their scientific publications (contained in Scopus, the WoS, and the RSCI),check citation levels and the h-index, filter data by the date of publication, and access the profiles of other researchers. 相似文献
20.
In economics the Research Papers in Economics (RePEc) network has become an essential source for the gathering and the spread of both existing and new economic research. Furthermore, it is currently the largest bibliometric database in economic sciences containing 33 different indicators for more than 30,000 economists. Based on this bibliographic information RePEc calculates well-known rankings for authors and academic institutions. We provide some cautionary remarks concerning the interpretation of some provided bibliometric measures in RePEc. Moreover, we show how individual and aggregated rankings can be biased due to the employed ranking methodology. In order to select key indicators describing and assessing research performance of scientist, we propose to apply principal component analysis in this data-rich environment. This approach allows us to assign weights to each indicator prior to aggregation. We illustrate the approach by providing a new overall ranking of economists based on RePEc data. 相似文献