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1.
MEDLINE is presented as a prototype for on-line bibliographic search systems. Creation of the data base, indexing language, and file organization are reviewed. On accessing the files, search logic is illustrated with a sample MEDLINE search. NLM's development of a document delivery system to complement its bibliographic retrieval system is discussed.  相似文献   

2.
The automatic text summary concerns the language industries. This work proposes a system automatically and directly transforming a source text into a reduced target text. The system deals exclusively with scientific and technical texts. It is based on the identification of specific expressions allowing an evaluation of the relevance of the sentence concerned, which can then be selected for the elaboration of the summary. The procedure consists in attributing a score to each sentence of the text and then eliminating those having the lowest scores. To produce the RAFI system (automatic summary based on indicative fragments), we resorted to the linguistic means of discourse analysis and the computing capacity of data processing instruments. This system could be adapted to Internet.  相似文献   

3.
The National Library of Medicine has offered TOXLINE, an online interactive bibliographic database of biomedical (toxicology) information since 1972. Files from 11 secondary sources comprise the TOXLINE database. The sources supplied bibliographic records in different formats and data structures. Data from each supplier's format had to be converted into a format suitable for TOXLINE. Three different, successive retrieval systems were used for the TOXLINE database which required reformatting of the data. Algorithms for generating terms for inverted file search methods were tested. Special characters peculiar to the scientific literature were evaluated during search term generation. Developing search term algorithms for chemical names in the scientific literature required techniques different from those used for nonscientific literature. Problems with replication of bibliographic records from multiple secondary sources are described. Some observations about online interactive databases since TOXLINE was first offered are noted.  相似文献   

4.
In this paper the features of a microprocessor based architecture for bibliographic retrieval system are illustrated. The proposed system consists of the following three functional blocks: the “query processor”, the “simple query executers” and the “answer composer”. The query processor parses the queries and breaks the complex query into simple queries. Each simple query executer is able to perform the operations satisfying a simple query. Finally, the answer composer puts together the results of all simple query executers and produces the response to the query originally raised. This machine will allow the implementation of a very powerfull query language. The basic design goals are the system modularity and a whatever complex query's fulfilment. This is achieved through the proposed query language and by means of the system architecture allowing high parallelism in the performed operations.  相似文献   

5.
The database to be used with an online bibliographic information system must meet a number of requirements which are often not satisfied by conventional database management systems. Most important of these is the requirement for full authority file control over the indexes to the database. This paper reviews the special requirements of a bibliographic database and shows how they are met in the database system of DOBIS-LIBIS (Dortmund Library System-Leuven Library System).  相似文献   

6.
冯华 《中国科技信息》2006,(11):151-152,158
液压随动系统是一种放大机构,也是一种自动调节系统.它在工程机械中应用广泛.本文在介绍液压随动系统工作原理的基础上、着重说明它在工程机械操纵系统中的应用.  相似文献   

7.
The Web, and consequently the information contained in it, is growing rapidly. Every day a huge amount of newly created information is electronically published in Digital Libraries, whose aim is to satisfy users' information needs.In this paper, we envisage a Digital Library not only as an information resource where users may submit queries to satisfy their daily information need, but also as a collaborative working and meeting space of people sharing common interests. Indeed, we will present a personalized collaborative Digital Library environment, where users may organize the information space according to their own subjective view, may build communities, may become aware of each other, may exchange information and knowledge with other users, and may get recommendations based on preference patterns of users.  相似文献   

8.
增强自动烹饪机器人燃气系统安全设计   总被引:1,自引:0,他引:1  
赵兴 《大众科技》2016,(2):87-89
自动烹饪机器人是近几年在机电、软件、烹饪等相关技术基础上开发出来的自动化设备,通过参照EN298:2012等相关欧洲标准要求,从系统结构和软硬件入手,对其核心的火力控制系统进行安全设计改进,有效的提升了烹饪机器人的安全水平。  相似文献   

9.
This article addresses file maintenance of subject headings in the National Library of Medicine's MEDLINE, a bibliographic retrieval file which is indexed using Medical Subject Headings (MeSH), NLM's subject authority. The emphasis is class maintenance in which sets of records in MEDLINE are changed by maintenance actions which reflect yearly changes in MeSH. Specific types of maintenance action are described with examples to highlight problem areas. Class maintenance failures, checking class maintenance, and informing end-users of MeSH changes resulting in class maintenance are discussed. Technical constraints and feasibility are not analyzed in detail; rather, the approach is geared toward requirements and impact of maintenance from the standpoint of vocabulary specialists and end-users. The article concludes with a brief statement on defining file maintenance policy.  相似文献   

10.
Ergonomics Abstracts Retrieval System (EARS) is an online bibliographic information search and retrieval system using the hierarchical subject classification of the Ergonomics Abstracts. EARS is designed using an inverted file organization and is implemented on CDC-Cyber. The data base of abstracts is organized using a fixed-length record format, where each logical record corresponds to a variable number of fixed-length physical records. Accordingly, an index for the identification of physical records from the logical records is used. The data base is inverted on a three-level hierarchical classification scheme and postings files are used for data base inversion. The data base is accessed after selectively traversing a 4-layer structure of indexes and postings files. EARS provides facilities to perform combinations of searches, limited searches, and certain editing functions. The system is currently used extensively by the Western New York Human Factors research community. The logical and physical designs of EARS, its interactive operational features, and its current expansions are described in this paper.  相似文献   

11.
Although its structure and strategies are rapidly evolving, the impact of the eHealth on the healthcare services is evident. Implementing eHealth systems on a national level can drastically enhance the health practices and services provided to the patients and community. Hence, the engineering of a new model and a holistic framework for eHealth systems becomes a necessity in order to have an effective implementation of these systems. The vast and rapid development in computers, communication, and Internet technologies has significantly affected the contemporary health systems. However, the complexity of the healthcare environment, the abundance of information, the compatibility and the lack of unified eHealth framework creates real challenges to present efficient and attractive eHealth model that encompasses all these elements. Furthermore, the security of the health records and the secure access to the information add a new dimension of complexity. This work presents a new model and an integrated framework for an efficient implementation of eHealth systems at the national level. The proposed model and framework successfully incorporate all the success factors of efficient eHealth system along with a new security model to access the health records.  相似文献   

12.
A study to compare the cost effectiveness of retrospective manual and on-line bibliographic searching is described. Forty search queries were processed against seven abstracting-indexing publications and the corresponding SDC/ORBIT data bases. Equivalent periods of coverage and searcher skill levels were used for both search models. Separate task times were measured for question analysis, searching, photocopying, shelving, and output distribution. Component costs were calculated for labor, information, reproduction, equipment, physical space, and telecommunications. Results indicate that on-line searching is generally faster, less costly, and more effective than manual searching. However, for certain query/information-source combinations, manual searching may offer some advantages in precision and turn-around time. The results of a number of related studies are reviewed.  相似文献   

13.
14.
Broken hypertext links are a frequent problem in the Web. Sometimes the page which a link points to has disappeared forever, but in many other cases the page has simply been moved to another location in the same web site or to another one. In some cases the page besides being moved, is updated, becoming a bit different to the original one but rather similar. In all these cases it can be very useful to have a tool that provides us with pages highly related to the broken link, since we could select the most appropriate one. The relationship between the broken link and its possible linkable pages, can be defined as a function of many factors. In this work we have employed several resources both in the context of the link and in the Web to look for pages related to a broken link. From the resources in the context of a link, we have analyzed several sources of information such as the anchor text, the text surrounding the anchor, the URL and the page containing the link. We have also extracted information about a link from the Web infrastructure such as search engines, Internet archives and social tagging systems. We have combined all of these resources to design a system that recommends pages that can be used to recover the broken link. A novel methodology is presented to evaluate the system without resorting to user judgments, thus increasing the objectivity of the results, and helping to adjust the parameters of the algorithm. We have also compiled a web page collection with true broken links, which has been used to test the full system by humans.  相似文献   

15.
This paper describes an applied document filtering system embedded in an operational watch center that monitors disease outbreaks worldwide. At the initial time of this writing, the system effectively supported monitoring of 23 geographic regions by filtering documents in several thousand daily news sources in 11 different languages. This paper describes the filtering algorithm, statistical procedures for estimating Precision and Recall in an operational environment, summarizes operational performance data and suggests lessons learned for other applications of document filtering technology. Overall, these results are interpreted as supporting the general utility of document filtering and information retrieval technology and offers recommendations for future applications of this technology.  相似文献   

16.
A prototype system is created that integrates a microfiche catalog into an online computer system for bibliographic control. Costs and operational data are collected and analyzed. The system permits the more economical microfiche storage of catalog records than would be feasible for comparable online magnetic disk storage. Experimental tests demonstrate the feasibility of the online microfiche catalog system for use in library technical services and retrieval of bibliographic data. The primary result of the project is the creation of a completely operational facility, including all equipment, software, procedures, and data bases necessary to demonstrate the system. A second set of results is derived from the experimental use of the system and the evaluation of costs and times for various operations. The cost effectiveness of the online microfiche catalog is demonstrated.  相似文献   

17.
基于关系数据库理论与技术,以企业技术创新管理决策问题为基点,结合先前的研究成果,将博弈分析模型引入到决策支持系统模型库中,主要应用简单的文本格式以及Excel文件格式加以实现,在模型库中首次加入了博弈分析模型的实现技术,从而为决策支持系统的设计提供支持.  相似文献   

18.
Bibliographic collections in traditional libraries often compile records from distributed sources where variable criteria have been applied to the normalization of the data. Furthermore, the source records often follow classical standards, such as MARC21, where a strict normalization of author names is not enforced. The identification of equivalent records in large catalogues is therefore required, for example, when migrating the data to new repositories which apply modern specifications for cataloguing, such as the FRBR and RDA standards. An open-source tool has been implemented to assist authority control in bibliographic catalogues when external features (such as the citations found in scientific articles) are not available for the disambiguation of creator names. This tool is based on similarity measures between the variants of author names combined with a parser which interprets the dates and periods associated with the creator. An efficient data structure (the unigram frequency vector trie) has been used to accelerate the identification of variants. The algorithms employed and the attribute grammar are described in detail and their implementation is distributed as an open-source resource to allow for an easier uptake.  相似文献   

19.
Given the growing importance of online social media platforms (OSM) in brand management, the authors attempt to extend the relationship between e-brand equity and repurchase intention with two mediator variables, namely visual appeal and e-preference in which willingness to pay a price premium (WPPP) serves as a moderator. Drawing on the perspective of digitalized engagement (PDE), the authors confirm the mediating effects on the e-brand equity-repurchase intention link while evidencing both positive and negative effects of WPPP on the linkage of e-brand equity and mediators. Contributions to theory, practice, and future studies are also provided.  相似文献   

20.
关忠诚  王琪  程刚 《科研管理》2005,26(1):108-112
监控管理系统对于现实问题意义重大。本文通过对故障定义、故障分级、系统评估以及数据模型的描述 ,提出了监控管理系统中的故障信息评估模型。最后给出了当前监控管理的问题及建议  相似文献   

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